ALBERT

All Library Books, journals and Electronic Records Telegrafenberg

X
feed icon rss

Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
Filter
  • Column liquid chromatography  (88)
  • Yeast  (41)
  • cell culture  (37)
  • Springer  (166)
  • American Meteorological Society
  • Periodicals Archive Online (PAO)
  • 1995-1999
  • 1990-1994  (166)
  • 1935-1939
  • 1991  (166)
Collection
Keywords
Publisher
  • Springer  (166)
  • American Meteorological Society
  • Periodicals Archive Online (PAO)
  • Wiley-Blackwell  (17)
Years
  • 1995-1999
  • 1990-1994  (166)
  • 1935-1939
Year
  • 1
    Electronic Resource
    Electronic Resource
    The involvement of trehalose in yeast stress tolerance (1991)
    Springer
    Journal of industrial microbiology and biotechnology 7 (1991), S. 191-195 
    Details
    ISSN: 1476-5535
    Keywords: Yeast ; Trehalose ; Osmotolerance ; Viability
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: Summary A total of 12 yeast strains from various genera were examined for their ability to produce ethanol in the presence of high concentrations of glucose. From these studies, the yeastsTorulaspora delbrueckii andZygosaccharomyces rouxii were observed to the most osmotolerant. These osmotolerant yeast strains were also observed to possess high concentrations of intracellular trehalose. Futhermore, these strains were found to be tolerant to long-term storage at −20°C and to storage at 4°C in beer containing 5% (v/v) ethanol. Cells containing high trehalose levels at the time of freezing or cold storage exhibited the highest cell viabilities. Trehalose concentration was observed to increase during growth on glucose, reaching a maximum after 24–48 h. Increasing the incubation temperature from 21 to 40°C also resulted in an increase in intracellular trehalose content. These results suggest that trehalose plays a role in enhancing yeast survival under environmentally stressful conditions.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01575882
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 2
    Electronic Resource
    Electronic Resource
    Activities ofβ-glucanases andβ-glucosidases during blastospore formation inSaccharomycopsis fibuligera (1991)
    Springer
    Journal of industrial microbiology and biotechnology 7 (1991), S. 263-268 
    Details
    ISSN: 1476-5535
    Keywords: Yeast ; β-Glucanase ; β-Glucosidase catabolite repression ; Sporulation
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: Summary The activities of three glycosidases, β-glucosidase and β(1,3)- and β(1,6)-glucanases have been monitored during growth and blastospore formation inSaccharomycopsis fibuligera. The assays were carried out on the cell-free culture and in a cell-free extract and a wall autolysate preparation from the growing cells. In complex medium containing 1% glucose an increase in the level of all three enzymes was associated with the transition from mycelium to blastospores. When the level of glucose was increased to 5% blastospore formation was repressed and the level of β-glucanases only increased at the end of the fermentation. The β-glucosidase activity increased during the growth phase. In a defined medium in which slow growth in a wholly yeast-like form was observed, growth was not associated with a high level of β-glucanase activity.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01577654
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 3
    Electronic Resource
    Electronic Resource
    Sugar uptake in a 2-deoxy-d-glucose resistant mutant ofSaccharomyces cerevisiae (1991)
    Springer
    Journal of industrial microbiology and biotechnology 7 (1991), S. 35-39 
    Details
    ISSN: 1476-5535
    Keywords: 2-Deoxy-d-glucose ; Yeast ; Catabolite repression ; Derepression
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: Summary The non-metabolizable and toxic glucose analogue 2-deoxy-d-glucose (2-DOG) has been widely employed to screen for regulatory mutants which lack catabolite repression. A number of yeast mutants resistant to 2-DOG have recently been isolated in this laboratory. One such mutant, derived from aSaccharomyces cerevisiae haploid strain, was demonstrated to be derepressed for maltose, galactose and sucrose uptake. Furthermore, kinetic analysis of glucose transport suggested that the high affinity glucose transport system was also derepressed in the mutant strain. In addition, the mutant had an increased intracellular concentration of trehalose relative to the parental strain. These results indicate that the 2-DOG resistant mutant is defective in general glucose repression.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01575600
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 4
    Electronic Resource
    Electronic Resource
    Mismatch-stimulated plasmid integration in yeast (1991)
    Springer
    Current genetics 19 (1991), S. 329-332 
    Details
    ISSN: 1432-0983
    Keywords: Mismatch repair ; Plasmid integration ; Yeast
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary A single base pair mismatch (G:T or A:C) in the CYC1 gene of the integrative plasmid pAB218 stimulates up to a five-fold integration into the yeast chromosome. Analysis of chromosomal sites of plasmid integration suggests that the mismatch-stimulated integration is not targeted as would be expected if crossovers, localised in the region of the mismatch, were a necessary step in mismatch repair. Instead, the observed mismatch-stimulated plasmid integration could be due to potentially recombinogenic structures formed during mismatch repair, such as single-stranded gaps or denatured DNA regions extending around the plasmid molecule.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00355064
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 5
    Electronic Resource
    Electronic Resource
    Properties of two nuclear pet mutants affecting expression of the mitochondrial oli1 gene of Saccharomyces cerevisiae (1991)
    Springer
    Current genetics 19 (1991), S. 343-351 
    Details
    ISSN: 1432-0983
    Keywords: PET genes ; Yeast ; Mitochondria ; ATP synthase
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary This study details the characteristics of two temperature-conditional pet mutants of yeast, strains ts1860 and ts379, which at the non-permissive temperature show deficiencies in the formation of three mitochondrially encoded subunits of the ATP synthase complex. By analysis of mitochondrial translation products, and of mitochondrial transcription in temperature shift experiments from the permissive (22°C) to the non-permissive (36°C) temperature, it was concluded that the nuclear mutations in both mutants primarily inhibit synthesis of ATP synthase subunit 9, and that reductions in subunit 8 and 6 synthesis are secondary pleiotropic effects. Following transfer to 36°C, cells of mutant ts379 display a near complete inhibition of subunit 9 synthesis within 1 h, coincident with a marked reduction in the level of the cognate oli1 mRNA. On the other hand, near complete inhibition of subunit 9 synthesis in strain ts1860 occurs after 3 h at 36°C, at which time there is little change in the level of subunit 9 mRNA. In both mutants the mRNA levels for subunits 6 and 8 are not significantly affected at the time of inhibition of subunit 9 synthesis. Provision of an alternative source of subunit 8, translated extra-mitochondrially for import into the organelle, does not overcome the mutant phenotype of either mutant at 36°C, confirming that subunit 8 is not the sole or primary deficiency in each mutant. The mutants indicate that the products of a least two nuclear genes (designated AEP1 and AEP2) are required for the expression of the mitochondrial oli1 gene and the synthesis of subunit 9. The product of the AEP1 gene (defective in mutant ts1860) is required for translation of oli1 mRNA while the AEP2 product (defective in mutant ts379) is essential either for the stability of oli1 mRNA or for the correct processing of precursor transcripts to the mature message.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00309594
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 6
    Electronic Resource
    Electronic Resource
    Linear DNA plasmids of Pichia inositovora are associated with a novel killer toxin activity (1991)
    Springer
    Current genetics 19 (1991), S. 389-393 
    Details
    ISSN: 1432-0983
    Keywords: Yeast ; Pichia inositovora ; Linear plasmids ; Killer toxin
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary Pichia inositovora, strain NRRL Y-18709, which contains three linear double-stranded DNA plasmids, pPinl-1, pPinl-2 and pPinl-3, was cured of these plasmids both by growing the strain in the presence of 50 μg/ml bisbenzimide, and by exposure to ultraviolet light. Both cured and uncured strains were tested for growth on a variety of carbon sources. No differences in growth response were detected, indicating no discernible involvement of the linear plasmids in the catabolism of these compounds. Culture supernatants of Pichia inositovora were shown to contain a substance larger than 100 kDa that is toxic to Saccharomyces cerevisiae, strain GS 1688. Toxin activity was optimal in YEPD assay plates containing 50 mM citrate buffer with a pH between 3.4 and 4.2. Culture supernatants from P. inositovora were also weakly active against Cephaloascus albidus, strain NRRL Y-18710, and Citeromyces matritensis, strain NRRL Y-18711. Concentrated supernatants from cured P. inositovora strains did not exhibit these activities, consistent with the hypothesis that this toxic activity is linear plasmid-encoded. Unlike the wellknown Kluyveromyces lactis system or the newly identified P. acaciae system, P. inositovora strains cured of their linear plasmids do not become detectably sensitive to toxin produced by the wild-type strain, suggesting a nonplasmid-encoded immunity function.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00309600
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 7
    Electronic Resource
    Electronic Resource
    Hyper-resistance to nitrogen mustard in Saccharomyces cerevisiae is caused by defective choline transport (1991)
    Springer
    Current genetics 19 (1991), S. 423-427 
    Details
    ISSN: 1432-0983
    Keywords: Yeast ; Molecular cloning ; Nitrogen mustard hyper-resistance ; Choline transport
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary The recessive hnm1 mutant allele is responsible for hyper-resistance to nitrogen mustard in Saccharomyces cerevisiae. Transformation with a single-copy HNM1 wild-type allele of such hyper-resistant mutants will restore wild-type sensitivity to nitrogen mustard. By contrast the presence of multi-copy vectors containing HNM1, in either a hyper-resistant hnm1 mutant or an HNM1 wild-type, will lead to a novel, mustard-sensitive phenotype unrelated to defects in DNA repair genes. Gene disruption of HNM1 revealed that this gene is nonessential for cells prototrophic for choline (CHO1) but lethal for cells with a cho1 genotype. Sensitivity to nitrogen mustard of wild-type HNM1, but not of hnm1 mutants, depends on the choline content of the growth medium, with cells grown in choline-free medium exhibiting the highest sensitivity. Sequencing of a 300 bp DNA fragment of HNM1 revealed the identity of this gene with the CTR locus, which is responsible for choline transport in Saccharomyces cerevisiae.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00312732
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 8
    Electronic Resource
    Electronic Resource
    The SNQ3 gene of Saccharomyces cerevisiae confers hyper-resistance to several functionally unrelated chemicals (1991)
    Springer
    Current genetics 19 (1991), S. 429-433 
    Details
    ISSN: 1432-0983
    Keywords: Mutagen hyper-resistance ; Yeast ; Base sequence ; Gene disruption
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary A multi-copy plasmid containing the SNQ3 gene confers hyper-resistance to 4-nitroquinoline-N-oxide (4NQO), Trenimon, MNNG, cycloheximide, and to sulfometuron methyl in yeast transformants. Restriction analysis, subcloning, and DNA sequencing revealed an open reading frame of 1950 bp on the SNQ3-containing insert DNA. Gene disruption and transplacement into chromosomal DNA yielded 4NQO-sensitive null mutants which were also more sensitive than the wild-type to Trenimon, cycloheximide, sulfometuron methyl, and MNNG. Hydropathic analysis showed that the SNQ3-encoded protein is most likely not membrane-bound, while the codon bias index points to low expression of the gene.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00312733
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 9
    Electronic Resource
    Electronic Resource
    Distribution of mitochondrial intron sequences among 21 yeast species (1991)
    Springer
    Current genetics 19 (1991), S. 89-94 
    Details
    ISSN: 1432-0983
    Keywords: Yeast ; Mitochondria ; Intron ; Mobile
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary The mitochondrial and nuclear genomes of 21 yeast species belonging to 12 genera have been tested for the presence of sequences similar to seven S. cerevisiae mitochondrial introns (Sc cox1.1,2,3,4,5c, Sc cob.4 and Sc LSU.1) and one K. lactis mitochondrial intron (Kl cox1.2). Some introns, (Sc cox1.4, Sc cob.4, Sc LSU.1 and Kl cox1.2-all group I type), are widely distributed and are found in species with either basidiomycete or ascomycete affinities. This distribution is suggestive of recent sequence transfer between species. The remaining S. cerevisiae introns cross react with an additional species but with no set pattern. Pulsed field gel electrophoretic studies confirm that none of the tested mitochondrial introns cross react with nuclear DNA. These introns are, therefore, mitochondria-specific. Seven strains of K. lactis exhibit striking variability in intron content. In contrast to all mitochondrial introns tested, two introns of nuclear genes (the K. lactis actin gene and the S. cerevisiae RP29B gene) are not detected beyond their source species.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00326288
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 10
    Electronic Resource
    Electronic Resource
    PDC6, a weakly expressed pyruvate decarboxylase gene from yeast, is activated when fused spontaneously under the control of the PDC1 promoter (1991)
    Springer
    Current genetics 20 (1991), S. 373-378 
    Details
    ISSN: 1432-0983
    Keywords: Yeast ; Pyruvate decarboxylase ; Gene expression ; Codon usage ; Gene fusion
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary Three structural genes encode the pyruvate decarboxylase isoenzymes in the yeast Saccharomyces cerevisiae. PDC1 and PDC5 are active during glucose fermentation where PDC1 is expressed about six times more strongly than PDC5. Expression of PDC6 is weak and seems to be induced in ethanol medium. Consequently, pdc1Δ pdc5Δ double mutants do not ferment glucose and do not grow on glucose medium. Spontaneous mutants, derived from such a pdc1 pdc5 strain, were isolated which could again ferment glucose. They showed pyruvate decarboxylase activity due to a duplication of PDC6. The second copy of PDC6 was expressed under the control of the PDC1 promoter, which was still present in the pdc1 strain. However, the resulting PDC1-PDC6 fusion gene could only partially substitute for PDC1: to achieve normal growth and high pyruvate decarboxylase activity strains carrying PDC1-PDC6 required a functional PDC5 gene which is dispensable in a PDC1 wild-type background. Thus, expression of PDC5 depends on the state of the PDC1 locus: low in the PDC1 wild-type background and high in PDC1-PDC6 fusion strains and, as shown previously, in pdc1 mutants. The activation of PDC5 expression in PDC1-PDC6 strains may be due to particular properties of the PDC1-PDC6 fusion protein or simply to the weaker expression of PDC1-PDC6 in comparison to the wild-type PDC1 gene.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00317064
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 11
    Electronic Resource
    Electronic Resource
    Characterization of a yeast nuclear gene, AEP2, required for accumulation of mitochondrial mRNA encoding subunit 9 of the ATP synthase (1991)
    Springer
    Current genetics 20 (1991), S. 53-61 
    Details
    ISSN: 1432-0983
    Keywords: AEP2 ; Yeast ; Mitochondria ; ATP synthase
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary The temperature-conditional pet mutant, ts379, of Saccharomyces cerevisiae fails to synthesize mitochondrial ATP synthase subunit 9 at the restrictive temperature due to mutation of a single nuclear locus, AEP2. The inability to synthesize subunit 9 correlates with a lowered accumulation of the cognate oli1 mRNA indicating that the AEP2 product is involved in oli1 transcript maturation or stabilization. The AEP2 gene has been isolated in this study from a wild-type yeast genomic library by genetic complementation of ts379 at the restrictive temperature. A 1740 nucleotide open-reading frame was observed that encodes a basic, hydrophilic protein of 67534 Da which possesses a putative mitochondrial address signal. Disruption of chromosomal DNA within this reading frame produced a non-conditional respiratory mutant unable to synthesize subunit 9, identifying the AEP2 gene. Hybridization analyses indicate that AEP2 is located on chromosome XIII and produces a 2.1 kb poly(A)+ transcript. Two additional open-reading frames were found in close proximity to that of AEP2. The three open-reading frames shared no significant homology with entries in several data bases.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00312765
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 12
    Electronic Resource
    Electronic Resource
    Repair of gamma ray-induced S1 nuclease hypersensitive sites in yeast depends on homologous mitotic recombination and a RAD18-dependent function (1991)
    Springer
    Current genetics 20 (1991), S. 33-37 
    Details
    ISSN: 1432-0983
    Keywords: Pulsed field gel-electrophoresis ; S1 nuclease sensitive sites ; Repair ; Yeast
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary Repair under non-growth conditions of DNA double-strand breaks (DSB) and chromatin sites sensitive to S1 endonuclease (SSS) induced by 60Cobalt-gamma rays were monitored in repair-competent and deficient strains of Saccharomyces cerevisiae by pulsed field gelelectrophoresis. In stationary-phase cells of a repair-competent RAD diploid, and an excision-deficient rad3-2 diploid, SSS are repaired as efficiently as DSB, whereas in a repair-competent RAD haploid, and a rad 50-1 diploid, neither SSS nor DSB are repaired. The rad18-2 diploid repairs DSB well but is defective in SSS repair. Obviously, SSS repair in yeast chromatin, like DSB repair, depends on recombination, but unlike DSB repair depends additionally on RAD18 function.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00312762
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 13
    Electronic Resource
    Electronic Resource
    Interactions between chromosomal omnipotent suppressors and extrachromosomal effectors in Saccharomyces cerevisiae (1991)
    Springer
    Current genetics 19 (1991), S. 243-248 
    Details
    ISSN: 1432-0983
    Keywords: Yeast ; Mistranslation ; ψ-factor
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary Chromosomal omnipotent suppressor mutations recovered in ψ+ strains of Saccharomyces cerevisiae were brought into ψ− cytoplasm. SUP46, SUP138 and SUP139 acted as dominant omnipotent suppressors in the ψ− cytoplasm though their suppressor activity was substantially reduced. SUP46 and SUP138 conferred recessive thermosensitivity and antibiotic sensitivity in ψ− cytoplasm as in ψ+ cytoplasm. On the other hand, sup111 through sup115, which acted as recessive omnipotent suppressors in the ψ+ cytoplasm, manifested no, or very low, suppressor activity in the ψ− cytoplasm. They, however, still enhanced the efficiency of the SUP29 tRNA suppressor in ψ− cytoplasm. A multicopy plasmid carrying the wild-type SUP35 gene enhanced the efficiency of sup111 in ψ− cytoplasm.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00355049
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 14
    Electronic Resource
    Electronic Resource
    Isolation and genetic study of p-fluoro-dl-phenylalanine-resistant mutants overproducing β-phenethyl-alcohol in Saccharomyces cerevisiae (1991)
    Springer
    Current genetics 20 (1991), S. 449-452 
    Details
    ISSN: 1432-0983
    Keywords: Yeast ; Mutant ; p-Fluoro-dl-phenylalanine ; β-Phenethyl-alcohol
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary p-Fluoro-dl-phenylalanine (PFP)-resistant mutants which produce a large amount of β-phenethyl-alcohol, a rose-like flavor component, were isolated from the isogenic strains X2180-1A and X2180-1B of Saccharomyces cerevisiae. Cells of these mutants accumulated phenylalanine and tryptophan more than 3-fold times that of wild-type cells, while they accumulated less than half the tyrosine. The activity of prephenate dehydrogenase (PDG) (EC 1.3.1.12) was markedly decreased while that of 3-deoxy-d-arabino-heptulosonate-7-phosphate synthase (EC 4.1.2.15) was increased. Genetic analysis revealed that the mutation occurred at the TYR1 locus, encoding PDG, and that the mutated TYR1 gene, tyr1-pfp, caused both PFP resistance and β-phenethyl-alcohol overproduction. This was supported by molecular genetic studies with cloned tyr1-pfp DNA.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00334770
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 15
    Electronic Resource
    Electronic Resource
    Isolation and characterization of S. cerevisiae mutants deficient in amino acid-inducible peptide transport (1991)
    Springer
    Current genetics 20 (1991), S. 457-463 
    Details
    ISSN: 1432-0983
    Keywords: Peptides ; Transport ; Regulation ; Yeast
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary The transport of small peptides into the yeast Saccharomyces cerevisiae is subject to complex regulatory control. In an effort to determine the number, and to address the function, of the components involved in peptide transport and its regulation, spontaneous mutants resistant to toxic di- and tripeptides were isolated under inducing conditions. Twenty-four mutant strains were characterized in detail and fell into two phenotypic groups; one group deficient in amino acid-inducible peptide uptake, the other with a pleiotropic phenotype including a loss of peptide transport. Complementation analysis of recessive mutations in 12 of these strains defĩned three groups; ptr1 (nine strains), ptr2 (two strains), and ptr3 (one strain). Isolation and screening of 31 additional N-methyl-N-nitro-N-Nitrosoguanidine (MNNG)-induced, peptide transport-deficient mutants produced one ptr3 and 30 ptr2 strains: no additional complementation groups were detected. Uptake of radiolabeled dileucine was negligible in ptr1 and ptr2 strains and was reduced by 65% and 90% in the two ptr3 mutants, indicating that all strains were defective at the transport step. We conclude that the S. cerevisiae amino acid-inducible peptide transport system recognizes a broad spectrum of peptide substrates and involves at least three components. One gene, PTR3, may play an indirect or regulatory role since mutations in this gene cause a pleiotropic phenotype.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00334772
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 16
    Electronic Resource
    Electronic Resource
    Polymorphisms in tandemly repeated sequences ofSaccharomyces cerevisiae mitodhondrial DNA (1991)
    Springer
    Journal of molecular evolution 32 (1991), S. 396-404 
    Details
    ISSN: 1432-1432
    Keywords: Yeast ; Mitochondrial DNA ; Polymirphism ; Repeated sequences
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary A spontaneously arising mitochondrial DNA (mtDNA) variant ofSaccharomyces cerevisiae has been formed by two exta copies of a 14-bp sequence (TTAATTAAATTATC) being added to a tandem repeat of this unit. Similar polymorphisms in tandemly repeated sequences have been found in a comparison between mtDNAs from our strain and others. In 5850 bp of intergenic mtDNA squence, polymorphisms in tandemly repeated sequences of three or more base pairs occur approximately every 400–500 bp whereas differences in 1–2 bp occur approximately every 60 bp. Some polymorphisms are associated wit optional G+C-rich sequences (GC clusters). Two such optional GC clusters and one A+T repeat polymorphism have been discovered in the tRNA synthesis locus. In addition, the variable presence of large open reading frames are documented and mechanisms for generating intergenic sequence diversity inS. cerevisiae mtDNA are discussed.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF02101279
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 17
    Electronic Resource
    Electronic Resource
    Sequence rearrangements at theori 7 region ofSaccharomyces cerevisiae mitochondrial DNA (1991)
    Springer
    Journal of molecular evolution 32 (1991), S. 439-442 
    Details
    ISSN: 1432-1432
    Keywords: Yeast ; Mitochondrial DNA ; ori ; rep ; Polymorphism
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary Threeori elements (ori 2,ori 5, andori 7) have been sequenced inSaccharomyces cerevisiae strain Dip 2 and compared to the equivalentori elements of a second strain (B). Bothori 2 andori 5 exhibit 98% base matching between strains Dip 2 and B. In contrast, the thirdori element (ori 7) exhibits extensive sequence rearrangements whereby a segment located downstream in the consensus strain occurs within theori structure in Dip 2. This represents a novel polymorphic form of the yeast mitochondrial genome.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF02101284
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 18
    Electronic Resource
    Electronic Resource
    Toxicity of the mycotoxins fumonisins B1 and B2 and Alternaria alternata f. sp. lycopersici toxin (AAL) in cultured mammalian cells (1991)
    Springer
    Mycopathologia 116 (1991), S. 97-104 
    Details
    ISSN: 1573-0832
    Keywords: Fumonisin B1 ; fumonisin B2 ; AAL toxin ; T-2 toxin ; mycotoxin ; Fusarium moniliforme ; bioassay ; cell culture
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Abstract Fumonisins B1 and B2 and AAL toxin are a series of structurally related mycotoxins. Fumonisins B1 and B2, produced by Fusarium moniliforme Sheldon induce toxic hepatitis and hepatomas in rats and leukoencephalomalacia in horses. The cancer-promotion assay which has been used to guide their purification is slow and consumes large amounts of sample. We have examined a series of cultured mammalian cell lines in order to develop a more rapid and sensitive bioassay system, which may be useful for examining structure-activity relationships and the mechanism(s) of action of these toxins. Of 9 rat hepatoma cell lines tested, all except the two most de-differentiated lines were sensitive to the three toxins, with a toxic response visible by 48 h. Approximate IC50 values for the most sensitive hepatoma line, H4TG, were 4, 2 and 10 μg/ml for fumonisins B1, B2 and AAL toxin, respectively „in 100 μl cultures. Among 15 cell lines from other sources, only MDCK dog kidney epithelial cells were sensitive (IC50 = 2.5, 2 and 5 μg/ml, respectively). Studies in co-cultures of sensitive and insensitive cell lines and in cultures of a sensitive cell line over a range of cell densities indicated that cytotoxicity of fumonisins B1 and B2 does not involve metabolite activation to a derivative stable enough to diffuse to adjacent cells.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00436371
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 19
    Electronic Resource
    Electronic Resource
    Modified culture method for human corneal epithelial cells (1991)
    Springer
    Methods in cell science 13 (1991), S. 45-48 
    Details
    ISSN: 1573-0603
    Keywords: cell culture ; corneal epithelium ; primary explant
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary An improved procedure for the primary culture of pure human corneal epithelial cells from corneal explants is described. Confluent monolayers of epithelial cells can be consistently produced from small segments of donor corneas regardless of donor age and without feeder layers. Incubating segments on collagen at the air-liquid interface significantly improves the yield of cells per cornea and shortens cell migration time as compared to culturing on plastic. Fibroblast contamination is eliminated by serum-free medium and confirmed by indirect immunofluorescent staining for keratin.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF02388203
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 20
    Electronic Resource
    Electronic Resource
    Culture of human renal cortex epithelial cells (1991)
    Springer
    Methods in cell science 13 (1991), S. 143-147 
    Details
    ISSN: 1573-0603
    Keywords: kidney ; renal cortex ; proximal tubule ; enzymatic dissociation ; cell culture
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary A procedure is described for the establishment and propagation of epithelial cell rich cultures derived from normal human kidney cortex (NHK-C cells). Cells are harvested from tissue fragments of donor human kidney by progressive enzymatic dissociation. NHK-C cultures are morphologically heterogeneous but exhibit, predominantly, the functional characteristics of cells of the kidney proximal tubule.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF02388118
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 21
    Electronic Resource
    Electronic Resource
    Effects of low nitrate and high sugar concentrations on anthocyanin content and composition of grape (Vitis vinifera L.) cell suspension (1991)
    Springer
    Plant cell reports 9 (1991), S. 500-504 
    Details
    ISSN: 1432-203X
    Keywords: anthocyanin ; cell culture ; nitrate ; sucrose ; Vitis vinifera
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract In pigmented cells of Vitis vinifera suspension cultures, best accumulation of anthocyanins was obtained when nitrate concentration was reduced from 25 mM to 6.25 mM and when sucrose concentration was increased from 88 mM to 132 mM. Under such conditions growth was greatly decreased. However, cell viability was maintained. The increases in anthocyanins in pigmented cells were due largely to increases in peonidin — glucoside. The high sucrose and the low nitrate concentrations can be one of the important culture factors in controlling of anthocyanin production by cell cultures.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00232105
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 22
    Electronic Resource
    Electronic Resource
    Chemical mutagenesis and DNA synthesis in cdc8, a DNA replication mutant of Saccharomyces cerevisiae (1991)
    Springer
    Current genetics 20 (1991), S. 471-474 
    Details
    ISSN: 1432-0983
    Keywords: Yeast ; DNA replication ; Chemical mutagenesis
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary Incubation of cdc8 mutants of the yeast Saccharomyces cerevisiae in YPD under permissive conditions, when DNA replication is taking place, prior to transfer to restrictive conditions, strongly stimulates induction of cdc + colonies of ethyl methane sulphonate (EMS)- and methyl methane sulphonate (MMS)-treated yeast strains HB23 (cdc8-1/cdc8-3), HB26 (cdc8-3/cdc8-3) and HB7 (cdc8-1/cdc8-1). After diepoxybutane (DEB) treatment, both the induction of cdc + colonies and their stimulation after incubation in YPD under permissive conditions is low. The results obtained show that stimulation of induction of cdc + colonies under permissive conditions occurs not only after UV-treatment, but also after treatment with such mutagens as EMS and MMS.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00334774
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 23
    Electronic Resource
    Electronic Resource
    Evidence that an endo-exonuclease controlled by the NUC2 gene functions in the induction of ‘petite’ mutations in Saccharomyces cerevisiae (1991)
    Springer
    Current genetics 20 (1991), S. 39-44 
    Details
    ISSN: 1432-0983
    Keywords: Petite mutation ; NUC2 nuclease ; Yeast ; RAD52 ; Ethidium bromide
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary Defects in the RAD52 gene of the yeast Saccharomyces cerevisiae reduce the levels of the NUC2 endo-exonuclease by approximately 90% compared to the levels in wild-type strains. To examine the potential role of this nuclease in the induction of mitochondrial ‘petite’ mutations, congenic RAD52 and rad52-1 haploids were subjected to treatment with ethidium bromide, a well-known inducer of these mutations. The rad52 strain showed a much higher resistance to ethidium bromide-induced petite formation than the corresponding wild-type strain. Two approaches were taken to confirm that this finding reflected the nuclease deficiency, and not some other effect attributable to the rad52-1 mutation. First, a multicopy plasmid (YEp213-10) carrying NUC2 was transformed into a RAD52 strain. This resulted in an increased fraction of spontaneous petite mutations relative to that seen for the same strain without the plasmid and sensitized the strain carrying the plasmid to peptite induction by ethidium bromide treatment. Second, a strain having a nuc2 allele that encodes a temperaturesensitive nuclease was treated with ethidium bromide at the restrictive and permissive temperatures. Petite induction was reduced under restrictive conditions. Enzyme assays revealed that the RAD52 (YEp213-10) strain had the highest level of antibody-precipitable NUC2 endo-exonuclease whereas the nuc2 and rad52 mutants had the lowest levels. Furthermore, addition of ethidium bromide to the reaction mixture stimulated the activity of the nuclease on double-stranded DNA. Peptite induction by antifolate-mediated thymine nucleotide depletion was also inhibited by inactivation of RAD52 indicating that the effect of reduced NUC2 endo-exonuclease was not restricted to ethidium bromide treatment. Taken collectively, these results indicate that the NUC2 gene product functions in the production of mitochondrial petite mutations.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00312763
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 24
    Electronic Resource
    Electronic Resource
    Ethanol improves the transformation efficiency of intact yeast cells (1991)
    Springer
    Current genetics 20 (1991), S. 1-3 
    Details
    ISSN: 1432-0983
    Keywords: Yeast ; Transformation ; Ethanol
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary A technique is described in which ethanol is used to improve the genetic transformation of intact yeast (Saccharomyces cerevisiae) cells pretreated with LiAc and PEG. Transformation efficiency was increased with increasing concentrations of ethanol with a peak at 10% concentration. The effect varies with different yeast strains and plasmids and up to a maximum of a 15-fold increase was observed.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00312757
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 25
    Electronic Resource
    Electronic Resource
    The TSM1 gene of Saccharomyces cerevisiae overlaps the MAT locus (1991)
    Springer
    Current genetics 20 (1991), S. 25-31 
    Details
    ISSN: 1432-0983
    Keywords: Yeast ; TSM1 sequence ; Essential gene ; MAT distal cloning
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary We have cloned the region from MAT to THR4 on chromosome III of Saccharomyces cerevisiae. Although the region is only 15 kb, the two loci are genetically separated by 22 cM. This is in sharp contrast to the very low level of recombination (2 cM in 22 kb) that is observed in the adjacent CRY1-MAT interval, and suggests that there may be a “hot spot” for recombination in the MAT-THR4 region. The DNA sequence of the first 4.4 kb distal to MAT reveals an open reading frame that we have identified as the essential gene, TSM1. Surprisingly, the TSM1 open reading frame of 1 410 amino acids extends into the MAT locus, such that the 3′-end of the MATα1 transcript ends 15 bp from the 3′-end of the TSM1 open reading frame.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00312761
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 26
    Electronic Resource
    Electronic Resource
    Complex interaction of yeast nuclear proteins with the enhancer/promoter region of SV40 (1991)
    Springer
    Current genetics 20 (1991), S. 359-363 
    Details
    ISSN: 1432-0983
    Keywords: Yeast ; Enhancer ; Transcriptional elements ; Transcriptional factors ; Regulation
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary Though highly complex enhancers found in animal cells have not been reported to occur in yeasts they are able to activate the transcription of adjacent genes in yeast cells. Saccharomyces cerevisiae expresses a large number of nuclear proteins that are able to recognize, and specifically bind to, the enhancer sequences of the SV40 animal tumor virus. The complexity of proteins that interact with different elements of the animal enhancers is similar in yeast and animal cell nuclear extracts. Most enhancer motifs, recognized by known trans-acting factors, are protected in footprinting experiments by yeast nuclear proteins.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00317062
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 27
    Electronic Resource
    Electronic Resource
    Isolation and primary structure of the ERG9 gene of Saccharomyces cerevisiae encoding squalene synthetase (1991)
    Springer
    Current genetics 20 (1991), S. 365-372 
    Details
    ISSN: 1432-0983
    Keywords: Saccharomyces cerevisiae ; Ergosterol ; Squalene synthetase ; Yeast
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary The ERG9 gene of Saccharomyces cerevisiae has been cloned by complementation of the erg9-1 mutation which affects squalene synthetase. From the 5kkb insert isolated, the functional gene has been localized on a DNA fragment of 2.5 kb. The presence of squalene synthetase activity in E. coli bearing the yeast DNA fragment isolated, indicates that the structural gene encoding squalene synthetase has been cloned. The sequence of the 2.5 kb fragment contains an open reading frame which could encode a protein of 444 amino acids with a deduced relative molecular mass of 51 600. The amino acid sequence reveals one to four potential transmembrane domains with a hydrophobic segment in the C-terminal region. The N-terminus of the deduced protein strongly resembles the signal sequence of yeast invertase suggesting a specific mechanism of integration into the membranes of the endoplasmic reticulum.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00317063
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 28
    Electronic Resource
    Electronic Resource
    Evolutionarily recent transfer of a group I mitochondrial intron to telomere regions in Saccharomyces cerevisiae (1991)
    Springer
    Current genetics 20 (1991), S. 411-415 
    Details
    ISSN: 1432-0983
    Keywords: Mitochondria ; Intron ; Telomere ; Yeast
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary The junctions between X and Y′ subtelomeric repeats in Saccharomyces cerevisiae usually contain a stretch of telomere sequences, (G1–3T)n. Two of three cloned X-Y′ junctions from strain YP1 have a replacement of about 200 bp of X, the internal telomere sequence, and 49 bp of Y′ by a 292 bp sequence. The first 227 bp of this insertion sequence are 100% identical to the fourth intron of cytochrome b. The rest of the insertion has homology to an unknown dispersed nuclear sequence. Recombination among subtelomeric regions can explain the nuclear distribution of this sequence and why telomeres can trap and maintain sequences that would otherwise be lost.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00317070
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 29
    Electronic Resource
    Electronic Resource
    AUG codons in the RNA leader sequences of the yeast PET genes CBS1 and SCO1 have no influence on translation efficiency (1991)
    Springer
    Current genetics 20 (1991), S. 465-469 
    Details
    ISSN: 1432-0983
    Keywords: In vitro mutagenesis ; PET-genes ; RNA-leader ; Ribosomal scanning ; Yeast
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary We report that the major transcription start sites of the yeast PET gene SCO1 are located at positions-149 and -125 relative to the AUG initiation codon of the SCO1 reading frame. The leader sequences of the resulting mRNAs possess a single AUG codon at position-49, which initiates a short open reading frame of three amino acids. The recent finding of a similar situation in the case of the PET gene CBS1 prompted us to address the question as to whether these AUG codons might play some role in the expression of these PET genes. After removal of the upstream AUG codons by site-directed mutagenesis, expression was monitored by use of lacZ fusions and compared to the respective wildtype constructs. Our data show that under all growth conditions tested the leader-contained AUG initiation codons have no significant influence on the expression of both PET genes.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00334773
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 30
    Electronic Resource
    Electronic Resource
    A mechanism for the loss of cytochrome P-450 in primary mouse hepatocytes (1991)
    Springer
    Molecular and cellular biochemistry 108 (1991), S. 151-156 
    Details
    ISSN: 1573-4919
    Keywords: cytochrome P-450 ; mitochondria ; heme ; hepatocytes ; mitochondrial DNA ; cell culture
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Chemistry and Pharmacology , Medicine
    Notes: Abstract This study examined various biochemical parameters such as mitochondria and mitochondrial DNA (mtDNA), total heme and cyto P450 content in fresh hepatocytes and dedifferentiated hepatocytes. These parameters were chosen in order to understand the dramatic decrease in drug metabolism in cultured hepatocytes. The data in this study shows a temporal decrease in cytochrome P450, total heme and also a decrease in mitochondria. Also, the ratio of mtDNA content to mitochondrial density was found to increase as hepatocytes underwent dedifferentiation. Stereological analysis of cell preparations provided a measure of mitochondrial density per cell area and mtDNA content was assessed by the use of a specific radiolabelled probe. This study demonstrates that a loss of the organelle which is partially responsible for synthesis of heme correlates with a decrease in cytochrome P450.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00233120
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 31
    Electronic Resource
    Electronic Resource
    Adrenergic hormones and control of cardiac myocyte growth (1991)
    Springer
    Molecular and cellular biochemistry 104 (1991), S. 35-43 
    Details
    ISSN: 1573-4919
    Keywords: α1-adrenergic receptors ; β-adrenergic receptors ; cardiac muscle ; cell culture ; gene expression ; protein kinase C
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Chemistry and Pharmacology , Medicine
    Notes: Abstract The molecular mechanisms of cardiac myocyte growth are relevant to important problems in cardiovascular disease. A cell culture model has been developed to explore the role of adrenergic hormones in cardiac myocyte growth and gene expression. Activation of a cardiac myocyte α1-adrenergic receptor by catecholamines induces hypertrophic growth of neonatal rat cardiac myocytes and initiates selective increases in contractile protein gene transcription. These effects on growth and gene expression do not depend on contractile activity. The cardiac myocytes contain at least two subtypes of α1-adrenergic receptors and at least three isoforms of protein kinase C (PKC). A distinct α1 receptor subtype may mediate hypertrophy and gene transcription. Different isoforms of PKC are translocated to different intracellular sites on activation, and there is evidence that the β-PKC isoform may be an element in the signal transduction pathway from an α1 receptor at the surface to the cardiac myocyte nucleus. Growth regulation through a β-adrenergic receptor can also be demonstrated in the culture model. The growth response mediated through a β-adrenergic receptor differs in several respects from that transduced through an al adrenergic receptor.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00229801
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 32
    Electronic Resource
    Electronic Resource
    Sequence analysis of a chalcone isomerase cDNA of Phaseolus vulgaris L. (1991)
    Springer
    Plant molecular biology 16 (1991), S. 167-169 
    Details
    ISSN: 1573-5028
    Keywords: Phaseolus vulgaris ; cell culture ; chalcone isomerase ; elicitor
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00017927
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 33
    Electronic Resource
    Electronic Resource
    Molecular cloning of a cDNA from Lupinus polyphyllus cell cultures encoding a ribosomal protein (rps16) (1991)
    Springer
    Plant molecular biology 16 (1991), S. 739-740 
    Details
    ISSN: 1573-5028
    Keywords: Lupinus polyphyllus ; cell culture ; cDNA clone ; ribosomal protein ; rps 16
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00023439
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 34
    Electronic Resource
    Electronic Resource
    Expression and stability of amplified genes encoding 5-enolpyruvylshikimate-3-phosphate synthase in glyphosate-tolerant tobacco cells (1991)
    Springer
    Plant molecular biology 17 (1991), S. 1127-1138 
    Details
    ISSN: 1573-5028
    Keywords: tobacco ; 5-enolpyruvylshikimate-3-phosphate synthase ; cDNA clone ; gene expression ; gene amplification ; glyphosate ; cell culture ; tolerance
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Two distinct cDNAs for 5-enolpyruvylshikimate-3-phosphate synthase (EPSPS) were obtained from a glyphosate-tolerant tobacco cell line. The cDNAs were 89% identical and the predicted sequences of the mature proteins were greater than 83% identical with EPSPS proteins from other plants. Tobacco EPSPS proteins were more similar to those from tomato and petunia than Arabidopsis. One cDNA clone, EPSPS-1, represented a gene that was amplified in glyphosate-tolerant cells, while the gene for EPSPS-2 was unaltered in these cells. Consequently, EPSPS-1 mRNA was more abundant in tolerant than unselected cells, whereas EPSPS-2 mRNA was at relatively constant levels in these cell lines. Exposure of unselected cells and tobacco leaves to glyphosate produced a transient increase in EPSPS mRNA. However, glyphosate-tolerant cells containing amplified copies of EPSPS genes did not show a similar response following exposure to glyphosate. A significant proportion of the EPSPS gene amplification was maintained when tolerant cells were grown in the absence of glyphosate for eight months. Plants regenerated from these cells also contained amplified EPSPS genes.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00028730
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 35
    Electronic Resource
    Electronic Resource
    Retention characteristics of chlorinated polycyclic aromatic hydrocarbons in normal phase HPLC. I. Chloro-added PAHs (1991)
    Springer
    Chromatographia 32 (1991), S. 334-340 
    Details
    ISSN: 1612-1112
    Keywords: Column liquid chromatography ; Normal phase separations ; Cyanopropyldimethyl silica ; Chloro-added polycyclic aromatic hydrocarbons ; Environmental samples
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Summary Retention characteristics in normal phase HPLC of highly biologically active chloro-added polycyclic aromatic hydrocarbons (PAHs) were studied. Silica, cyanopropyldimethylsilyl- and aminopropylsilyl- modified stationary phases were investigated. Retention properties of chloroadded PAHs on these phases were shown to be strongly influenced by the number of chloro-additions. This is due to the strong polarity of the methylene carbon at the chloro-addition site. Active silica had a strongly degrading effect on the unstable chloro-added PAHs during separation. Aminopropylsilica did not exhibit sufficient selectivity towards chloro-added PAHs when compared to chlorosubstituted PAHs. Cyanopropyldimethylsilica was shown to be applicable to a group separation of chloro-added and chloro-substituted PAHs. A fast clean-up procedure for chloro-added PAHs in complex samplesis outlined. It involves an initial elimination of more polar substances on a short open column with strongly deactivated silica and a subsequent separation on a cyanopropyldimethylsilyl HPLC column in normal phase mode.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF02321430
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 36
    Electronic Resource
    Electronic Resource
    Chromatography in pore networks II — The role of structure and adsorption in the band broadening (1991)
    Springer
    Chromatographia 32 (1991), S. 345-349 
    Details
    ISSN: 1612-1112
    Keywords: Column liquid chromatography ; Column packings ; Pore size distribution ; Diffusion and adsorption ; Band broadening
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Summary The complex intraparticle structure typical of chromatographic column packings has been analyzed by use of an equivalent network model which emphasizes pore size distribution and connectivity. Special attention is given as to the way in which diffusion and adsorption interact and display modified peak spreading characteristics according to the morphology of the pore space. This study reveals a very significant increase in the column band broadening over that expected from physical adsorption which can arise from particular distributions of pore sizes. This has implications for designing packings which take advantage of the separating power due to adsorption but do not compromise the resolution of the chromatographic system.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF02321432
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 37
    Electronic Resource
    Electronic Resource
    Studies of serum-free medium for the generation of lymphokine-activated killer cells (1991)
    Springer
    Cytotechnology 6 (1991), S. 39-47 
    Details
    ISSN: 1573-0778
    Keywords: cell culture ; lymphocyte ; lymphokine-activated killer cell ; recombinant interleukin 2 ; serum-free medium
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine , Process Engineering, Biotechnology, Nutrition Technology
    Notes: Abstract We examined a serum-free medium (designated as TYI 101) for the generation of lymphokine-activated killer (LAK) cells from human lymphocytes, regional lymph node lymphocytes (RLNL) and peripheral blood lymphocytes (PBL). TYI 101 medium consisted of, in addition to nutrient mixture, transferrin, insulin, fetuin, sodium selenite, 2-mercaptoethanol, o-phosphorylethanolamine, chick egg yolk and porcine kidney extract. These hormones were effective for supporting RLNL proliferation as assessed by (3H)-thymidine uptake. When human lymphocytes from two different sources were cultivated with recombinant interleukin 2 (rIL-2) in TYI 101 medium, LAK activity was generated. In cultures of PBL from a healthy donor, LAK cells were generated in TYI 101 medium as efficiently as in RPMI 1640 medium supplemented with 10% human AB-type serum (RPMI-AB). In cultures of RLNL from lung cancer patients, LAK activity obtained in TYI 101 medium was about sixty-five percent of that in RPMI-AB. However, the addition of a small amount of AB-type serum improved the generation of LAK activity, LAK cell expansion, and cell viability in TYI 101 medium. We conclude that TYI 101 medium can be used for the generation of LAK cells from human lymph node lymphocytes with supplementation of none or only a reduced amount of human serum.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00353701
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 38
    Electronic Resource
    Electronic Resource
    Development of a new culture system for human lymphokine-activated killer cells: Comparison with a conventional static culture method (1991)
    Springer
    Cytotechnology 7 (1991), S. 75-83 
    Details
    ISSN: 1573-0778
    Keywords: adoptive immunotherapy ; cell culture ; cell culture apparatus ; Interleukin-2 ; lymphokine-activated killer cells
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine , Process Engineering, Biotechnology, Nutrition Technology
    Notes: Abstract We recently developed a new culture system based on dialysis perfusion (designated JCC-device) for the generation and expansion of human lymphokine-activated killer (LAK) cells (Murata et al., 1990). More recently we have scaled up the volume of the culture vessel of the JCC-device from 100 ml to 400 ml for clinical use. In the present study, using this new 400 ml JCC-device, we cultured human lymph node lymphocytes (LNL) obtained from 8 surgical patients with primary lung cancer, and investigated the cellular characteristics in comparison with a conventional batchwise culture system using tissue culture dishes. With the JCC-device, the cell density reached a maximum 2.7×107 cells/ml with greater than 90% viability by the appropriate exchange of perfusion medium and by making additions at the appropriate intervals for recombinant interleukin-2 (rIL-2). The expansion fold of LNL with the JCC-device, ranging 6.6- to 19.2-fold (mean 13.8-fold), was not significantly different from that in dish cultures. There was no marked difference in cell surface phenotypes between the two culture systems in 7 out of 8 cases. As for LAK activity of LNL, the JCC culture was either superior or equal in 4 out of 8 cases, but inferior in the other 4 cases to the conventional dish cultures. In the latter cases, the usage of serum for the JCC culture was limited, which might have resulted in the low LAK activity. The JCC-device was able to reduce the consumption of basal medium, rIL-2 and serum by 20%, 84% and 96%, respectively compared to the conventional tissue culture systems. The JCC-device improved the routine performance of adoptive immunotherapy with LAK cells and rIL-2.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00350913
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 39
    Electronic Resource
    Electronic Resource
    A new method for the encapsulation of mammalian cells (1991)
    Springer
    Cytotechnology 7 (1991), S. 121-130 
    Details
    ISSN: 1573-0778
    Keywords: cell culture ; cellulose sulphate ; encapsulation ; monoclonal antibodies ; poly-dimethyl-diallyl-ammoniumchloride
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine , Process Engineering, Biotechnology, Nutrition Technology
    Notes: Abstract A new encapsulation method was developed for the cultivation of mammalian cells. The capsules were produced using a solution of sodium cellulose sulphate (CS)(1.5%) and poly-dimethyl-diallyl-ammoniumchloride (PDMDAAC). When CS droplets fell into the precipitation bath consisting of a 2% solution of PDMDAAC, immediately a membrane at the interphase was built up. The influences of varying encapsulation process parameters on capsule characteristics, cell growth, and monoclonal antibody production were tested. This new method showed advantages when compared to other methods mainly due to time simplicity of the whole process.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00350918
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 40
    Electronic Resource
    Electronic Resource
    Serum-free culture of carcinoma cell lines (1991)
    Springer
    Cytotechnology 5 (1991), S. 31-46 
    Details
    ISSN: 1573-0778
    Keywords: serum-free ; cell culture ; carcinoma
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine , Process Engineering, Biotechnology, Nutrition Technology
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00365532
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 41
    Electronic Resource
    Electronic Resource
    Influence of temperature on the proliferative response of rainbow trout gonadal fibroblasts to cortisol and RU 486 (1991)
    Springer
    Fish physiology and biochemistry 9 (1991), S. 261-269 
    Details
    ISSN: 1573-5168
    Keywords: Cortisol ; RU 486 ; temperature ; rainbow trout ; cell culture ; [3H]-Thymidine
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract The rainbow trout gonadal cell line, RTG-2, which survives temperatures from 0 to 28°C and proliferates at 5 to 26°C, responded to cortisol from 28°C to 0°C by influencing [3H]-thymidine incorporation into DNA. Over the normal temperature range of rainbow trout, 10–22°C, cortisol inhibited [3H]-thymidine incorporation. The antiglucocorticoid RU 486 had no effect on [3H]-thymidine incorporation at these temperatures and blocked the response to cortisol. Another antiglucocorticoid RU 362 also had no effect but was less effective in blocking the cortisol response. During incubation at 28°C this inhibitory response to cortisol was detected inconsistently during the first 24 h but was observed consistently during the second 24 h. At 0°C, cortisol and RU 486 had no effect during short treatments, but a 60 h exposure to either steroid stimulated [3H]-thymidine incorporation over a 48 h labelling period. These results suggest that temperature shifts between 10–22°C, do not change the direction of a response to cortisol and support the use of the upper portion (20–22°C) of the temperature range for studies on salmonid cells in culture.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF02265147
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 42
    Electronic Resource
    Electronic Resource
    TFS1: A suppressor of cdc25 mutations in Saccharomyces cerevisiae (1991)
    Springer
    Molecular genetics and genomics 230 (1991), S. 241-250 
    Details
    ISSN: 1617-4623
    Keywords: Yeast ; Saccharomyces cerevisiae ; Adenylyl cyclase ; CDC25 ; RAS
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary The TFS1 gene of Saccharomyces cerevisiae is a dosage-dependent suppressor of cdc25 mutations. Overexpression of TFS1 does not alleviate defects of temperature-sensitive adenylyl cyclase (cdc35) or ras2 disruption mutations. The ability of TFS1 to suppress cdc25 is allele specific: the temperature-sensitive cdc25-1 mutation is suppressed efficiently but the cdc25-5 mutation and two disruption mutations are only partially suppressed. TFS1 maps to a previously undefined locus on chromosome XII between RDN1 and CDC42. The DNA sequence of TFS1 contains a single long open reading frame encoding a 219 amino acid polypeptide that is similar in sequence to two mammalian brain proteins. Insertion and deletion mutations in TFS1 are haploviable, indicating that TFS1 is not essential for growth.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00290674
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 43
    Electronic Resource
    Electronic Resource
    Genome organization of the linear plasmid, pSKL, isolated from Saccharomyces kluyveri (1991)
    Springer
    Molecular genetics and genomics 226 (1991), S. 97-106 
    Details
    ISSN: 1617-4623
    Keywords: Yeast ; Linear plasmid ; Saccharomyces kluyveri ; Kluyveromyces lactis ; Killer plasmid
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary We have determined the complete nucleotide sequence of the linear DNA plasmid, pSKL, isolated from Saccharomyces kluyveri. Sequence analysis showed that pSKL has a high (A+T) content of 71.7%, and that there are 10 open reading frames (ORFs) larger than 250 nucleotides. All 10 ORFs were shown to be transcribed in S. kluyveri cells by S1 nuclease mapping analysis. The localization of ORFs, direction of transcription, and the predicted amino acid sequences of each ORF were quite similar to that of pGKL2, one of the killer plasmids found in Kluyveromyces lactis. The amino acid sequences of the largest two ORFs (ORF2 and ORF6) have homology with several DNA polymerases and RNA polymerases, respectively.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00273592
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 44
    Electronic Resource
    Electronic Resource
    Characterization of products of TY1-mediated reverse transcription in Saccharomyces cerevisiae (1991)
    Springer
    Molecular genetics and genomics 226 (1991), S. 145-153 
    Details
    ISSN: 1617-4623
    Keywords: Retrotransposons ; Reverse transcription ; Ty elements ; Yeast
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary Transposition of the yeast transposable element, Ty, has been shown to require a reverse transcription process. By analysing the extrachromosomal Tyspecific nucleic acid molecules associated with overproduced Ty virus-like particles (Ty-VLPs), we identified several reverse transcribed cDNA strands. Most of them resemble the characteristic intermediates of the reverse transcription process described for authentic retroviruses: a (−) strong-stop DNA strand covalently bound to an RNA primer, two elongated (−) strands with one or two long terminal repeat (LTR) sequences and a (+) strong-stop DNA. Surprisingly, complete (+) strands and full-length linear duplex Ty DNA could not be detected. The structural features of two additional (÷) strands may indicate some differences between the mechanisms of (+) strand synthesis in Ty and other retrotransposons or retroviruses.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00273598
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 45
    Electronic Resource
    Electronic Resource
    Characterization of the yeast ARG5,6 gene: determination of the nucleotide sequence, analysis of the control region and of ARG5,6 transcript (1991)
    Springer
    Molecular genetics and genomics 226 (1991), S. 154-166 
    Details
    ISSN: 1617-4623
    Keywords: Yeast ; Arginine ; Sequence ; Regulation ; Control region
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary In Saccharomyces cerevisiae, the ARG5,6 gene encodes acetylglutamyl-P reductase and acetylglutamate kinase, two arginine anabolic enzymes which are localized in the mitochondria. The synthesis of both enzymes is co-ordinately controlled by arginine and by three regulatory proteins (ARGRI, ARGRII, and ARGRIII). The ARG5,6 gene was cloned by complementation of an arg5 mutant strain. A subclone containing an EcoRI fragment of about 3.2 kb which complements the arginine requirement was sequenced. This 3163 by sequence contains only one long open reading frame of 2589 nucleotides encoding a protein of 863 amino acids. The size of this protein is in agreement with the length of the unique transcript determined by Northern hybridization. The measurements of ARG5,6 mRNA under various regulatory conditions show no correlation with the enzyme levels. As in other arginine biosynthetic and catabolic genes, the regulation by arginine through the three ARGR proteins thus involves a post-transcriptional control mechanism. By in vitro mutagenesis we created point mutations and deletions in the 5′ non-coding region of the ARG5,6 gene which allowed us to define the primary target of ARGR control. Specific regulation involves two regions: one located between the putative TATA element and the transcriptional initiation site and the second between this site and the first ATG.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00273599
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 46
    Electronic Resource
    Electronic Resource
    Immunological identification of yeast SCO1 protein as a component of the inner mitochondrial membrane (1991)
    Springer
    Molecular genetics and genomics 229 (1991), S. 413-420 
    Details
    ISSN: 1617-4623
    Keywords: SCO1 ; Cytochrome oxidase ; Membrane protein ; Mitochondria ; Yeast
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary The SCO1 gene of Saccharomyces cerevisiae encodes a 30 kDa protein which is specifically required for a post-translational step in the accumulation of subunits 1 and 2 of cytochrome c oxidase (COXI and COXII). Antibodies directed against a β-Gal::SCO1 fusion protein detect SCO1 in the mitochondrial fraction of yeast cells. The SCO1 protein is an integral membrane protein as shown by its resistance to alkaline extraction and by its solubilization properties upon treatment with detergents. Based on the results obtained by isopycnic sucrose gradient centrifugation and by digitonin treatment of mitochondria, SCO1 is a component of the inner mitochondrial membrane. Membrane localization is mediated by a stretch of 17 hydrophobic amino acids in the amino-terminal region of the protein. A truncated SCO1 derivative lacking this segment, is no longer bound to the membrane and simultaneously loses its biological function. The observation that membrane localization of SCO1 is affected in mitochondria of a rho 0 strain, hints at the possible involvement of mitochondrially coded components in ensuring proper membrane insertion.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00267464
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 47
    Electronic Resource
    Electronic Resource
    Multicopy CUP1 plasmids enhance cadmium and copper resistance levels in yeast (1991)
    Springer
    Molecular genetics and genomics 225 (1991), S. 363-368 
    Details
    ISSN: 1617-4623
    Keywords: Yeast ; Metallothionein gene ; Cadmium resistance
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary A 3.3 kb fragment of yeast genomic DNA was isolated by screening a genomic library constructed in the high copy number 2 micron plasmid YEp351 vector for clones capable of enhancing the degree of resistance of Saccharomyces cerevisiae strain MW3070-8B to cadmium. The insert contained two complete copies of the CUP1 gene open reading frame (183 bp), including the upstream promoter sequences (450 bp) with two conserved metal responsive cis-acting elements. Northern analysis showed that addition of cadmium (0.02 μM) or copper (50 μM) to overnight liquid cultures of yeast induced expression of CUP1 transcripts from both chromosomal and plasmid-borne gene copies. The cloned 3.3 kb DNA in a high copy number plasmid restored copper resistance to the sensitive strain LS70-313Δ, deleted for the CUP1 gene (cup1Δ), but failed to restore cadmium resistance. Thus, CUP1 gene expression in yeast appears to be influenced differently by cadmium and copper ions. Resistance to heavy metal poisoning resulted from enhanced gene product levels attributable to amplification of the CUP1 gene as well as to increased transcriptions. Two distinct gene product levels mediate cadmium and copper resistance; a higher gene product level was required to confer cadmium resistance.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00261675
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 48
    Electronic Resource
    Electronic Resource
    Positive and negative elements upstream of the meiosis-specific glucoamylase gene in Saccbaromyces cerevisiae (1991)
    Springer
    Molecular genetics and genomics 226 (1991), S. 383-392 
    Details
    ISSN: 1617-4623
    Keywords: Meiosis ; Sporulation ; Northern hybridization ; Regulatory circuit ; Yeast
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary The SGA1 gene encoding glucoamylase is specifically expressed late in meiotic development of the yeast Saccharomyces cerevisiae. We found that accumulation of both enzyme activity and transcripts was regulated negatively by both nutritional signals and a haploid-specific negative regulator gene of meiosis, RME1, and positively by the inducer genes for meiosis, IME1 and IME2. To study the role of sequences upstream of the SGA1 gene in its expression and regulation, we generated internal deletions in the 5′ non-coding region of the gene and chimeric genes with portions of the upstream sequence inserted into a reporter gene. By analyzing the expression of these genes, we have identified both a 19 by upstream activation sequence (UAS) and a 49 by negatively regulating element (NRE). The UAS activated transcription with no requirement for heterozygosity at the mating-type locus, but this activation was still under negative control by nutrients. The NRE showed no UAS-like activity but conferred IME2-dependent (or meiosis-specific) expression on a heterologous promoter. These results suggest that meiosis-specific expression of the SGA1 gene is established by a regulatory hierarchy including positive and negative factors, the actions of which are mediated through the two separate upstream regulatory elements, UAS and NRE, respectively. Also, that two independently acting cascades exist for the regulation of SGA1 expression: one transduces both the mating-type and nutritional signals and includes the IME2 product, which acts to relieve the repression through NRE ; and another transduces only the nutritional signal independently of the above pathway and inhibits positive factors acting on UAS.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00260650
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 49
    Electronic Resource
    Electronic Resource
    Expression in yeast of a cDNA copy of the K2 killer toxin gene (1991)
    Springer
    Molecular genetics and genomics 227 (1991), S. 127-136 
    Details
    ISSN: 1617-4623
    Keywords: Yeast ; Killer toxin ; Immunity
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary A cDNA copy of the M2 dsRNA encoding the K2 killer toxin ofSaccharomyces cerevisiae was expressed in yeast using the yeastADH1 promoter. This construct produced K2-specific killing and immunity functions. Efficient K2-specific killing was dependent on the action of the KEX2 endopeptidase and the KEX1 carboxypeptidase, while K2-specific immunity was independent of these proteases. Comparison of the K2 toxin sequence with that of the K1 toxin sequence shows that although they share a common processing pathway and are both encoded by cytoplasmic dsRNAs of similar basic structure, the two toxins are very different at the primary sequence level. Site-specific mutagenesis of the cDNA gene establishes that one of the two potential KEX2 cleavage sites is critical for toxin action but not for immunity. Immunity was reduced by an insertion of two amino acids in the hydrophobic amino-terminal region which left toxin activity intact, indicating an independence of toxin action and immunity.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00260717
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 50
    Electronic Resource
    Electronic Resource
    Mitochondrial mutations restricting spontaneous translational frameshift suppression in the yeast Saccharomyces cerevisiae (1991)
    Springer
    Molecular genetics and genomics 227 (1991), S. 306-317 
    Details
    ISSN: 1617-4623
    Keywords: Yeast ; Mitochondria ; Frameshift ; Suppression ; Restriction
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary The +1 frameshift mutation, M5631, which is located in the gene (oxi1) for cytochrome c oxidase II (COXII) of the yeast mitochondrial genome, is suppressed spontaneously to a remarkably high extent (20%–30%). The full-length wild-type COXII produced as a result of suppression allows the mutant strain to grow with a “leaky” phenotype on non-fermentable medium. In order to elucidate the factors and interactions involved in this translational suppression, the strain with the frameshift mutation was mutated by MnCl2 treatment and a large number of mutants showing restriction of the suppression were isolated. Of 20 mutants exhibiting a strong, restricted, respiration-deficient (RD) phenotype, 6 were identified as having mutations in the mitochondrial genome. Furthermore, genetic analyses mapped one mutation to the vicinity of the gene for tRNAPro and two others to a region of the tRNA cluster where two-thirds of all mitochondrial tRNA genes are encoded. The degree of restriction of the spontaneous frameshift suppression was characterized at the translational level by in vivo 35S-labeling of the mitochondrial translational products and immunoblotting. These results showed that in some of these mutant strains the frameshift suppression product is synthesized to the same extent as in the leaky parent strain. It is suggested that more than one +1 frame-shifted product is made as a result of suppression in these strains: one is as functional as the wild-type COXII, the other(s) is (are) non-functional and prevent leaky growth on non-fermentable medium. A possible mechanism for this heterogenous frameshift suppression is discussed.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00259684
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 51
    Electronic Resource
    Electronic Resource
    The GAM1/SNF2 gene of Saccharomyces cerevisiae encodes a highly charged nuclear protein required for transcription of the STA1 gene (1991)
    Springer
    Molecular genetics and genomics 228 (1991), S. 270-280 
    Details
    ISSN: 1617-4623
    Keywords: SNF2 sequence ; Transcriptional regulator ; Gene expression ; Glucoamylase ; Yeast
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary We have cloned and sequenced the GAM1 gene which is required for transcription of the STA1 gene encoding an extracellular glucoamylase in Saccharomyces cerevisiae var. diastaticus. Complementation tests indicated that GAM1 is the same gene as SNF2 which is required for derepression of the SUC2 gene encoding invertase. Accumulation of SNF2 RNA was not regulated by the GAM2 and GAM3 genes which are also required for STA1 expression. The SNF2 gene was predicted to encode a 194 kDa highly charged protein with a glutamine-rich tract. A bifunctional SNF2-lacZ fusion protein was shown by immunofluorescence microscopy to be localized to the nucleus, suggesting that the SNF2 protein is located in the nucleus.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00282476
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 52
    Electronic Resource
    Electronic Resource
    The KNS1 gene of Saccharomyces cerevisiae encodes a nonessential protein kinase homologue that is distantly related to members of the CDC28/cdc2 gene family (1991)
    Springer
    Molecular genetics and genomics 229 (1991), S. 1-9 
    Details
    ISSN: 1617-4623
    Keywords: Protein kinase ; Yeast ; CDC28 ; Cell cycle
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary A novel protein kinase homologue (KNS1) has been identified in Saccharomyces cerevisiae. KNS1 contains an open reading frame of 720 codons. The carboxy-terminal portion of the predicted protein sequence is similar to that of many other protein kinases, exhibiting 36% identity to the cdc2 gene product of Schizosaccharomyces pombe and 34% identity to the CDC28 gene product of S. cerevisiae. Deletion mutations were constructed in the KNS1 gene. kns1 mutants grow at the same rate as wild-type cells using several different carbon sources. They mate at normal efficiencies, and they sporulate successfully. No defects were found in entry into or exit from stationary phase. Thus, the KNS1 gene is not essential for cell growth and a variety of other cellular processes in yeast.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00264206
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 53
    Electronic Resource
    Electronic Resource
    Possible involvement of the yeast POLIII DNA polymerase in induced gene conversion (1991)
    Springer
    Molecular genetics and genomics 229 (1991), S. 353-356 
    Details
    ISSN: 1617-4623
    Keywords: DNA polymerase ; Gene conversion ; Yeast
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary In Saccharomyces cerevisiae, three different DNA polymerase complexes, POLI, POLII and POLIII, are known to be involved in DNA replication. The catalytic subunit of POLIII is encoded by the essential CDC2 gene. The existence of different thermosensitive non-complementing mutants of CDC2 offers the possibility of using a genetic approach to investigate the involvement of POLIII in induced gene conversion. When cdc2 heteroallelic cells were irradiated and incubated under restrictive conditions, almost no induction of thermoresistant cells could be detected, suggesting an essential role for POLIII in mitotic gene conversion events.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00267455
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 54
    Electronic Resource
    Electronic Resource
    Association of cytochrome b translational activator proteins with the mitochondrial membrane: implications for cytochrome b expression in yeast (1991)
    Springer
    Molecular genetics and genomics 230 (1991), S. 177-185 
    Details
    ISSN: 1617-4623
    Keywords: Translational activation ; Cytochrome b ; Mitochondria ; Yeast ; CRS1 ; CBS2
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary The products of the nuclear genes CBS1 and CBS2 are both required for translational activation of mitochondrial apocytochrome b in yeast. We report the intramitochondrial localization of both proteins by use of specific antisera. Based on its solubilization properties the CBS1 protein is presumed to be a component of the mitochondrial membrane; the detergent concentrations needed to release CBS1 from mitochondria are almost the same as for cytochrome c 1. In contrast, CBS2 behaves like a soluble protein, with some characteristics of a membrane-associated protein. A model is presented for translational activation of cytochrome b, which might also be applicable to translational regulation of other mitochondrial genes.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00290666
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 55
    Electronic Resource
    Electronic Resource
    Relative contributions of MCM1 and STE12 to transcriptional activation of a- and α-specific genes from Saccharomyces cerevisiae (1991)
    Springer
    Molecular genetics and genomics 227 (1991), S. 197-204 
    Details
    ISSN: 1617-4623
    Keywords: Yeast ; Transcription ; a- and α-specific genes ; MCM1 ; STE12
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary We have examined the relative contributions of MCM1 and STE12 to the transcription of the a-specific STE2 gene by using a 367 by fragment from the STE2 5′-noncoding region to drive expression of a reporter lacZ gene. Mutation of the MCM1 binding site destroyed MCM1 · α2-mediated repression in α cells and dramatically reduced expression in a cells. The residual expression was highly stimulated by exposure of cells to pheromone. Likewise, the loss of STE12 function reduced lacZ expression driven by the wild-type STE2 fragment. In the absence of both MCM1 and STE12 functions, no residual expression was observed. Thus, the STE2 fragment appears to contain two distinct upstream activation sequences (UASs), one that is responsible for the majority of expression in cells not stimulated by pheromone, and one that is responsible for increased expression upon pheromone stimulation. In further support of this idea, a chemically synthesized version of the STE2MCM1 binding site had UAS activity, but the activity was neither stimulated by pheromone nor reduced in ste12 mutants. Although transcription of aspecific genes also requires both MCM1 and STE12, these genes differ from a-specific genes in that they have a single, MCM1-dependent UAS system. The activity of the minimal 26 by UAS from the α-specific STE3 gene was both stimulated by pheromone and reduced in ste12 mutants. These data suggest that at α-specific genes STE12 and MCM1 exert their effects through a single UAS.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00259671
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 56
    Electronic Resource
    Electronic Resource
    Mitochondrial inner membrane protease 1 of Saccharomyces cerevisiae shows sequence similarity to the Escherichia coli leader peptidase (1991)
    Springer
    Molecular genetics and genomics 228 (1991), S. 167-176 
    Details
    ISSN: 1617-4623
    Keywords: Mitochondria ; Yeast ; Protein targeting ; PET2858 ; Inner membrane protease 1
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary The nuclear yeast mutant pet ts2858 is defective in the removal of pre-sequences from the mitochondrially encoded cytochrome oxidase subunit II (COXII) and the processing intermediate of cytochrome b 2 (Cytb 2), a nuclear gene product. In order to identify the genetic lesion in this mutant we have cloned and characterized a DNA region which complements the pet ts2858 mutation. The DNA sequence revealed three open reading frames, one of which is responsible for the complementation. A 570 by reading frame represents the structural gene PET2858, as demonstrated by in vitro mutagenesis, gene expression from a foreign promoter, and allelism tests. PET2858 encodes a 21.4 kDa protein, which is essential for growth on non-fermentable carbon sources and for the proteolytic processing of COXII and the Cytb 2 intermediate. When the N-terminus of the PET2858 protein is fused to a reporter protein, the resulting hybrid molecule is imported into mitochondria. Interestingly, the N-terminal half of the deduced PET2858 protein exhibits 30.7% amino acid identity to the leader peptidase of Escherichia coli. These results suggest that PET2858 codes for a mitochondrial inner membrane protease (IMP1) or at least a subunit of it. This protease is involved in protein processing and export from the mitochondrial matrix.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00282462
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 57
    Electronic Resource
    Electronic Resource
    Effects of high ammonium concentrations on growth and anthocyanin formation in grape (Vitis vinifera L.) cell suspension cultured in a production medium (1991)
    Springer
    Plant cell, tissue and organ culture 27 (1991), S. 169-174 
    Details
    ISSN: 1573-5044
    Keywords: ammonium ; anthocyanin ; cell culture ; growth kinetics ; production medium ; Vitis vinifera
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Cultivating Vitis vinifera cell suspensions in a production medium which is characterized by high sucrose and low nitrate concentrations (132 mM and 6.25 mM respectively) repressed growth but enhanced the intracellular accumulation of anthocyanins, especially peonidin 3-glucoside. Increasing the ammonium concentration of the production medium from 2 to 8–16 mM increased growth and decreased the accumulation of anthocyanins and peonidin 3-glucoside specifically. Instead, peonidin 3-p-coumaroylglucoside accumulated. At 24 mM ammonium concentration, growth was inhibited and accumulation of peonidin 3-p-coumaroylglucoside was significant (p〈0.05) and represented 42% of total anthocyanins after 12 days of culture compared with 19% in the production medium with 2 mM ammonium.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00041286
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 58
    Electronic Resource
    Electronic Resource
    Ferric chelate reduction by suspension culture cells and roots of soybean: A kinetic comparison (1991)
    Springer
    Plant and soil 130 (1991), S. 75-80 
    Details
    ISSN: 1573-5036
    Keywords: cell culture ; FeHEDTA ; Glycine max ; iron chelate reduction ; iron nutrition ; soybean
    Source: Springer Online Journal Archives 1860-2000
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Notes: Abstract The abilities of suspension cultures and intact roots of soybean (Glycine max L. cv. Hawkeye) to reduce ferric chelate were compared. Ferric chelate was supplied as ferric hydroxyethylethylenediaminetriacetic acid (FeHEDTA) and reduction was measured spectrophotometrically using bathophenan-throlinedisulfonic acid (BPDS) as the ferrous scavenger. Ferric chelate reduction by cell suspension cultures showed typical saturation kinetics; however, no difference was observed between cells that had been continuously grown with Fe (+Fe) and those that had been grown for four days without added Fe (−Fe). Values for Km and Vmax, determined from a Lineweaver-Burk plot, were 57 μM and nmoles mg-1 dry weight for the +Fe cells and 50 μM and 22 nmoles mg-1 dry weight for the -Fe cells, respectively. Ferric chelate reduction by Fe-deficient roots also exhibited saturation kinetics, while roots grown with adequate Fe did not reduce ferric chelate. The Km and Vmax values for Fe-deficient roots were 45 μM and 20 nmoles mg-1 dry weight, respectively, and did not differ from values obtained for cells in culture. This study offers strong evidence that the mechanism responsible for the reduction of ferric chelate is the same for cultured cells and roots and that the process is controlled at the cellular level. We propose that suspension cultures can be used as an alternative to intact roots in the study of ferric chelate reduction.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00011858
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 59
    Electronic Resource
    Electronic Resource
    Actual, potential and speculative applications of seaweed cellular biotechnology: some specific comments on Gelidium (1991)
    Springer
    Hydrobiologia 221 (1991), S. 181-194 
    Details
    ISSN: 1573-5117
    Keywords: callus ; cell culture ; domestication ; protoplast ; tissue culture
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Cellular biotechnology is a promising application in the propagation and selection of superior strains of seaweeds. Although axenic cultures, organogenetic tissue cultures, vegetative micro-propagation, callus induction and high yields of agar from calli have been described for several species of Gelidium, a number of basic problems remain to be solved. These include standardized methods for obtaining axenic cultures, identification of requirements for organic nutrients, PGR's, cellular disorganization and reorganization, somaclonal variation and somatic incompatibilities. Future progress in seaweed biotechnology will depend on the resolution of many of these problems.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00028374
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 60
    Electronic Resource
    Electronic Resource
    Experiments with culture media for planarian cells (1991)
    Springer
    Hydrobiologia 227 (1991), S. 187-192 
    Details
    ISSN: 1573-5117
    Keywords: Turbellaria ; planaria ; cell culture ; leucine uptake
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract We have tested various conditions for the culture of cells dispersed from planarians. The cells were procurred by digestion of planarian tissue in pronase and filtering through a nylon mesh. Using incorporation of L-[3H]leucine into protein as a gauge of cell growth, we found that the optimum salt concentration was about 50% of that for mammalian cells (about 160 mOsm) and that optimum pH was about 8. Sera from several species and a tetrapeptide (Arg-Gly-Asp-Ser, the cell-attachment sequence in fibronectin) greatly increased leucine uptake and extended cell survival up to a period of about two weeks. Various growth factors and some other substances tested had no effect on uptake of leucine, cell morphology, or survival. A few other compounds tested were cytotoxic. None of the experimental media promoted cell proliferation.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00027601
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 61
    Electronic Resource
    Electronic Resource
    Study of a factor produced by suspension-cultured Pinus radiata cells which enhances cell growth at low inoculum densities (1991)
    Springer
    Plant cell, tissue and organ culture 26 (1991), S. 53-59 
    Details
    ISSN: 1573-5044
    Keywords: cell culture ; cell wall ; conditioned medium ; inoculum density ; low inoculum growth factor ; Pinus radiata
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Pinus radiata cells in suspension culture abruptly lose their growth capacity when diluted below a critical inoculum density. This threshold density can be lowered by adding the supernatant (conditioned medium) from healthy cultures which have been grown separately at high densities. Fresh medium is conditioned rapidly indicating that the factor responsible is either potent or produced rapidly. Activity-response curves increase progressively with concentration indicating that still greater effect may be obtained if the factor can be concentrated following separation from other medium components. The effect is not mimicked by a number of candidate compounds (including auxins, cytokinins, polyamines and vitamins). Partial characterisation studies indicate that the factor is relatively small (〈1 000 dalton) and possibly an oligosaccharide. It is considered that the factor is an essential structural component of the walls of expanding cells where it is reversibly-bound.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00116610
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 62
    Electronic Resource
    Electronic Resource
    Two types of asymmetric acetylcholinesterase in chick hindlimb muscle: Developmental profiles,in Vivo and in cell culture, and recovery after inactivation (1991)
    Springer
    Cellular and molecular neurobiology 11 (1991), S. 191-201 
    Details
    ISSN: 1573-6830
    Keywords: acetylcholinesterase ; asymmetric-form types ; chick hindlimb muscle ; development ; cell culture ; diisopropylfluorophosphate inactivation
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary 1. We have analyzed the behavior of two types of asymmetric molecular forms (A forms) of acetylcholinesterase (AChE) during development of chick hindlimb muscle,in vivo and in cell culture, and upon irreversible inactivation of peroneal muscle AChE with diisopropylfluorophosphate (DFP)in vivo. 2. In agreement with previous developmental studies on chick muscle, globular forms of AChE (G forms) are predominant in chick hindlimb at early embryonic ages, being gradually replaced by A forms as hatching (and, therefore, onset of locomotion) approaches. Of the two A-form types, AI appears and accumulates significantly earlier than AII, so that A/G and II/I ratios higher than 1 are attained only at about hatching time. 3. Cultures prepared from 11-day chick embryo hindlimb myoblasts express both types of A forms, with a combined activity of 27% of total AChE after 12 days in culture. AI forms appear again earlier and are much more abundant than type II asymmetric species through the life span of cultures. 4. All AChE activity in the peroneal muscle is irreversibly inactivated by injection of DFPin vivo. The recovery of A forms follows the same sequence described for normal development, with a delayed and slower recovery of AII forms as compared with AI. 5. Several hypotheses involving tail polypeptides or tissue target molecules, or posttranslational interconversion, are proposed to help explain the earlier appearance and accumulation of AI forms in chick muscle.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00712809
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 63
    Electronic Resource
    Electronic Resource
    Accumulation of peonidin 3-glucoside enhanced by osmotic stress in grape (Vitis vinifera L.) cell suspension (1991)
    Springer
    Plant cell, tissue and organ culture 24 (1991), S. 49-54 
    Details
    ISSN: 1573-5044
    Keywords: anthocyanin ; cell culture ; osmotic potential ; reverse-phase HPLC ; Vitis vinifera
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Cell cultures of grapes, Vitis vinifera L. cv Gamay Fréaux were grown under different conditions of external osmotic potential induced by an increase of sucrose concentration or by the addition of mannitol to the culture medium. Addition of 82 mM mannitol or increasing sucrose concentration to 132 mM had similar effects on repressing growth. Cyanidin 3-glucoside, peonidin 3-glucoside and peonidin 3-p-coumaroylglucoside are three main anthocyanins of Vitis cells. Increasing osmotic potential from −0.43 MPa to −0.8 MPa in the medium resulted in a significant intracellular accumulation of anthocyanin especially peonidin 3-glucoside in the pigmented cells. High osmotic potential appears to stimulate the methylation of anthocyanins. Osmotic potential is an important culture factor and may be useful in the controlling of anthocyanin production and composition.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00044265
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 64
    Electronic Resource
    Electronic Resource
    Increased anthraquinone production in Galium vernum cell cultures induced by polymeric adsorbents (1991)
    Springer
    Plant cell, tissue and organ culture 24 (1991), S. 207-210 
    Details
    ISSN: 1573-5044
    Keywords: anthraquinone production ; cell culture ; Galium vernum ; polymeric adsorbents ; secretion
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Anthraquinones produced by suspension cultures of Galium vernum are completely retained intracellularly. Surprisingly, in the presence of some polymeric adsorbents anthraquinones are partially released into the culture medium. The secretion and in situ removal stimulates anthraquinone production in cell cultures of Galium vernum. Best results were obtained with Wofatit ES and Amberlite XAD-2.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00033478
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 65
    Electronic Resource
    Electronic Resource
    Isolation and characterization of Daucus carota L. cell lines resistant to 2-deoxy-D-glucose (1991)
    Springer
    Plant cell, tissue and organ culture 25 (1991), S. 147-152 
    Details
    ISSN: 1573-5044
    Keywords: cell culture ; Daucus carota ; 2-deoxy-D-glucose ; invertase ; selection
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Variant carrot (Daucus carota L.) cell lines resistant to the growth inhibitory effects of the glucose analogue 2-deoxy-D-glucose (dGlc) were isolated utilizing a feeder plate technique. Growth of sensitive cells was less than 7.5% of controls on medium supplemented with 3.0 mM dGlc, whereas resistant variants achieved growth ranging from 15% to 70% of that in controls. Increased levels of acid invertase activity in variant cell lines in response to dGlc in the culture medium, together with decreased sensitivity of the acid invertase enzyme (EC 3.2.1.26) to dGlc, is proposed as one of several potential mechanisms contributing to the observed dGlc resistance.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00042186
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 66
    Electronic Resource
    Electronic Resource
    Morphologic identification of epithelial cell types of the human tracheo-bronchus in cell culture (1991)
    Springer
    Methods in cell science 13 (1991), S. 5-11 
    Details
    ISSN: 1573-0603
    Keywords: bronchial epithelium ; cell culture ; intermediate filaments ; carbohydrate cytochemistry ; lectins ; peroxidase-labeled lectins
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary A protocol is presented for correlating the morphology of human bronchial epithelial cells after Papanicolaou staining with their periodic acid schiff (PAS)/AB-reactivity, intermediate filament type, and the pattern of staining with lectins having specific affinities for glycoconjugates:griffionia simplicifolia (GSA-IB4; terminal alpha-d-galactose),Dolichos biflorus (DBA,N-acetyl-d-galactosamine). The combination of these stains identified differentiation markers in morphologic studies of normal, transformed, and malignant bronchial epithelial cells in culture.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF02388197
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 67
    Electronic Resource
    Electronic Resource
    Use of the pH-sensitive dye BCECF to study pH regulation in cultured human kidney proximal tubule cells (1991)
    Springer
    Methods in cell science 13 (1991), S. 205-209 
    Details
    ISSN: 1573-0603
    Keywords: pH ; NH 4 + ; BCECF ; human kidney ; proximal tubule ; cell culture
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary This protocol describes the use of the pH-sensitive, intracellularly trapped dye 2′,7′-bis (2-carboxyethyl), 5 (and -6) carboxyfluorescein (BCECF), to characterize the pH regulating mechanisms in cultured human kidney proximal tubule cells. This is a reliable method for intracellular pH measurements and is applicable to single cells, cell suspensions, and confluent cultures.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF02388128
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 68
    Electronic Resource
    Electronic Resource
    A direct fluorimetric DNA assay on cell suspensions (1991)
    Springer
    Methods in cell science 13 (1991), S. 285-288 
    Details
    ISSN: 1573-0603
    Keywords: DNA ; fluorimetry ; fibroblast ; cell culture
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary An improved direct fluorimetric assay is described using bisbenzimidazol fluorescence at 356 nm excitation and 458 nm emission wavelengths. The turbidity of the medium was shown to have no effect on fluorescence under an absorbance of 0.2 at the excitation wavelength. The method was evaluated by comparisons with a colorimetric DNA assay and cell counting. The linearity of fluorescence was determined up to 15μg/ml of DNA. The method was very reproducible and sensitive to detect 10 ng/ml of DNA and may be used for cell suspensions containing around 5000 cells/ml or more.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF02388262
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 69
    Electronic Resource
    Electronic Resource
    Fetal bovine oviduct epithelial cell monolayers: Method of culture and identification (1991)
    Springer
    Methods in cell science 13 (1991), S. 289-294 
    Details
    ISSN: 1573-0603
    Keywords: fetal bovine ; oviduct ; cell culture ; microscopy ; immunocytochemistry
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary Bovine epithelial cell monolayers were obtained for culture from fetal oviduct after in situ trypsinization. Isolated ciliated and secretory cells obtained in high yield with good viability were suspended in B2-MENEZO'S medium supplemented with 7.5% fetal bovine serum FBS. The plated primary cultures reached confluency 2 days after initial seeding, producing a monolayer of cohesive polygonal cells with viability of 85 to 95%. Associated with this large epithelial cell population, ciliated cells as well as a few elongated spindle cells were observed. After the first subculture the ciliated cells disappeared and the epithelial cells in the monolayer grew more rapidly to confluence than adult-derived cultures. In addition, frozen-thawed oviduct epithelial cells also maintained a level of 75 to 85% viability during postthaw subculture. The epithelial cells maintained their secretory activity in culture as indicated by electron microscopy and immunocytochemistry. The cell culture monolayers contained keratin, a specific cytoskeletal component of epithelial cells. This culture system may offer benefits for in vitro culture of mammalian embryos.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF02388263
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 70
    Electronic Resource
    Electronic Resource
    Williopsis salicorniae Sp. Nov. (1991)
    Springer
    Antonie van Leeuwenhoek 59 (1991), S. 125-127 
    Details
    ISSN: 1572-9699
    Keywords: Taxonomy ; Williopsis Salicorniae ; Yeast
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Four strains of an undescribed species of the genus Williopsis were isolated from brackish water. A description of the new species, Williopsis salicorniae (type strain, CBS 8071, NRRL Y-12834), is given.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00445656
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 71
    Electronic Resource
    Electronic Resource
    A method for estimating oxygen availability of stationary plant cell cultures in liquid media (1991)
    Springer
    Plant cell, tissue and organ culture 26 (1991), S. 195-201 
    Details
    ISSN: 1573-5044
    Keywords: Brassica napus ; cell culture ; diffusion ; liquid medium ; oxygen availability ; protoplast culture
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract A method for estimating the oxygen availability in plant cell cultures grown in stationary liquid media (e.g. many protoplast cultures) was developed. The method is based on short-term measurements of respiration rate versus oxygen concentration on a sample of cells, suspended in liquid media. From such data it is possible to estimate the oxygen concentration at the bottom of a stagnant liquid culture, by calculating the amount of oxygen reaching the cells by diffusion. As an example, rape (Brassica napus L. cv. Omega) hypocotyl protoplasts were grown with different oxygen concentrations at the site of the cells, obtained by varying the cell density, the height of the liquid layer and the oxygen content of the gas phase. The number of surviving calli was positively correlated with the estimated oxygen availability in the range between 60 and 350 μM O2, below 60 μM all cells died. This indicates that oxygen availability can be a limiting factor in the range usually encountered in protoplast cultures, and that the method can be useful when designing optimal growth conditions for stationary cultures of plant cells.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00039944
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 72
    Electronic Resource
    Electronic Resource
    l-Phenylalanine ammonia-lyase in suspension culture cells of spruce (Picea abies) (1991)
    Springer
    Plant cell, tissue and organ culture 27 (1991), S. 267-274 
    Details
    ISSN: 1573-5044
    Keywords: cell culture ; enzyme induction ; fungal elicitor ; l-phenylalanine ammonia-lyase ; Picea abies
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract The activity of l-phenylalanine ammonia-lyase (PAL) (EC 4.3.1.5) was determined in seedlings, callus cells, cell suspension cultures and in young needles of spruce (Picea abies) (L.) (Karst). PAL activity increased up to 10 fold in response to transferring suspension cultured cells into new cultivation medium. PAL was also induced about 10 fold when callus cells were transferrd into liquid medium. The increase was transient and it required the presence of a carbohydrate. In cell suspension cultures, grown in the dark (white cells), but not in light-grown cultures (green cells), PAL activity was induced up to 30 fold by UV-light. With a cell wall preparation of Rhizosphaera kalkhoffii, a forest pathogenic fungus, used as elicitor, the activity of PAL could be induced more than 10 fold. The degree of induction depended on the elicitor concentration. Induction was prevented by cycloheximide but not by actinomycin D.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00157590
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 73
    Electronic Resource
    Electronic Resource
    Proteoglycan synthesis in cultures of murine retinal neurons and photoreceptors (1991)
    Springer
    Cellular and molecular neurobiology 11 (1991), S. 579-591 
    Details
    ISSN: 1573-6830
    Keywords: proteoglycans ; glycosaminoglycans ; mouse retina ; photoreceptors ; retinal neurons ; cell culture
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary 1. In recent years, a number of histochemical and immunocytochemical studies have suggested that proteoglycans, particularly those in the inter-photoreceptor matrix, exhibit altered distributions in several murine models for retinal degenerations. We are using a cell culture system to characterize the proteoglycans synthesized by neurons and photoreceptors derived from mouse retina, with the long-term goal of analyzing their role in retinal degenerations. 2. In this study we describe initial studies using cells derived from the retinas of normal mice. Cultures of retinal neurons and photoreceptors, which were free of glial, epithelia, or endothelial cells, were labeled with3H-glucosamine and35SO4. Proteoglycans isolated from the medium and cell layer were analyzed on the basis of charge, relative hydrodynamic size, and glycosaminoglycan content. 3. The studies indicate that the cultures actively synthesize proteoglycans. The medium contained predominantly chondroitin sulfate/dermatan sulfate, while the cell layer had a higher proportion of heparan sulfate, indicating a differential distribution between the two compartments.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00741447
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 74
    Electronic Resource
    Electronic Resource
    Nutrient optimization for high density biological production applications (1991)
    Springer
    Cytotechnology 5 (1991), S. 15-30 
    Details
    ISSN: 1573-0778
    Keywords: high density ; cell culture ; serum-free medium ; hybridoma ; CHO cells ; virus production ; insect cells ; adoptive immunotherapy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine , Process Engineering, Biotechnology, Nutrition Technology
    Notes: Conclusion At the 1989 annual meeting of the U.S. Tissue Culture Associations, Ricahrd am, a leading investigator in the serum-free nutrient requirements of cultured cells, commented on the process of medium development. He noted that a survey of major media manufacturers revealed that, among the top selling mammalian cell culture media formulations, most were nearly thirty years old. This commentary is noteworthy considering the tremendous changes in cell culture understanding and derived applications which have emerged over these three decades. Fastidious cell types relatively unknown to investigators of the 1950s and 1960s are now being cultivated in defined, serum-free environments. Culture environments range from limiting dilution clonal recoveries to maintenance cultures approaching tissue densities. While research applications continue to predominate, applications of cell culture have expanded to the engineered production of biopharmaceuticals, to replacement of animal models for toxicology testing, and to the preservation, activation and expansion of human cells, tissues and organs. It is likely that future nutrient medium development will be predicated upon the design of a minimal number of defined formulations of relatively generic utility to a broad class of cell types. Analytical techniques derived from those described herein will be exploited in the user laboratory and in collaboration with the supplier to optimize the nutrient composition for the desired biological response.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00365531
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 75
    Electronic Resource
    Electronic Resource
    Growth and protein production kinetics of a murine myeloma cell line transfected with the human growth hormone gene (1991)
    Springer
    Cytotechnology 5 (1991), S. 223-231 
    Details
    ISSN: 1573-0778
    Keywords: cell culture ; kinetics ; Ig promoter/enhancer ; plasmacytoma ; recombinant protein production
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine , Process Engineering, Biotechnology, Nutrition Technology
    Notes: Abstract A model mammalian cell system for the production of recombinant proteins was investigated. Murine myeloma cells which had lost the ability to produce both heavy and light chain immunoglobulin molecules were transfected with a vector containing the immunoglobulin heavy chain promoter and enhancer elements linked to the human growth hormone gene. The growth kinetics of G32, a clonal isolate, were found to be similar to both the parent myeloma and hybridomas. However, production of hGH by G32 was growth associated, rather than as a secondary metabolite as is the case for hybridomas. In addition, G32 produced hGH at molar levels greater than most hybridomas.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00556292
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 76
    Electronic Resource
    Electronic Resource
    Primary cell culture from embryos of the Japanese scallop Mizuchopecten yessoensis (Bivalvia) (1991)
    Springer
    Cytotechnology 6 (1991), S. 49-54 
    Details
    ISSN: 1573-0778
    Keywords: Bivalvia ; cell culture ; embryo ; mitosis ; scallop
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine , Process Engineering, Biotechnology, Nutrition Technology
    Notes: Abstract Primary cell cultures obtained from embryos of Mizuchopecten yessoensis (Bivalvia) survived for four months. Although the number of cells progressively decreased during the cultivation, mitotic cells were observed both at the first stages and at the end. A possibility of growing marine invertebrates cells in long term primary culture is discussed.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00353702
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 77
    Electronic Resource
    Electronic Resource
    Characterization of endosteal osteoblasts isolated from human maxilla and mandible: An experimental system for biocompatibility tests (1991)
    Springer
    Cytotechnology 7 (1991), S. 39-48 
    Details
    ISSN: 1573-0778
    Keywords: cell culture ; endosteal human osteoblasts ; maxilla ; mandible ; titanium ; biocompatibility ; alkaline phosphatase
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine , Process Engineering, Biotechnology, Nutrition Technology
    Notes: Abstract Fragments of cancellous and cortical bone from human maxilla and mandible were cultured by the explant technique. Cells isolated by trypsinization of primary cultures were characterized as osteoblasts on the basis of intracellular alkaline phosphatase activity, the constituents of the extracellular matrix, and response to human parathormone (PTH). In culture, the osteoblasts often gave rise to superposed clumps of large cells whose cytoplasm contained endoplasmic reticulum, numerous mitochondria, vacuoles, and a dense network of intermediate filaments, often at the level of the plasma membrane. In the presence of vitamin C and 1,25-dihydroxyvitamin D3, the osteoblasts produced an extracellular matrix composed of collagen type I and various non-collagenous proteins, including osteocalcin. Biochemical test results were comparable to those reported for osteoblasts of other origins (rat calvaria, human iliac crest), and namely elevated intracellular alkaline phosphatase activity and cAMP accumulation in response to stimulation by human PTH (1–34). Osteoblasts isolated in this manner were cultured in the presence of pure titanium disks to determine the effects of exposure to this metal. Electron microscopy revealed few significant differences in cell growth and specific enzyme activity compared to control osteoblasts grown on plastic dishes, reflecting the excellent biologic and biochemical relationship between the osteoblasts and pure titanium. This experimental system thus appears suitable for biocompatibility studies, and in particular, evaluation of dental implants.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00135637
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 78
    Electronic Resource
    Electronic Resource
    Separation and characterization of a viscosity index improver copolymer by high-performance liquid chromatography (1991)
    Springer
    Chromatographia 31 (1991), S. 71-74 
    Details
    ISSN: 1612-1112
    Keywords: Column liquid chromatography ; Size exclusion chromatography ; Styrene-methacrylate polymers ; IR and UV spectroscopy ; Lubricating oils additives
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Summary Characterization of a poly(styrene-alkyl methacrylate) viscosity index improver according to its chemical composition distribution and molecular weight distribution was carried out by liquid adsorption chromatography, size exclusion chromatography and infrared and ultraviolet spectrophotometry. The industrial polymer was fractionated by liquid chromatography using silica gel as adsorbent and a mixture of 1,2-dichloroethane and methanol as mobile phase. Each fraction was analyzed by size exclusion chromatography and infrared and ultraviolet spectroscopy. The number average molecular weight ranged from 10000 to 36000 and the weight average molecular weight from 19000 to 264000. The styrene content of the various fractions analysed was between 29.5% and 72.2%.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF02290500
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 79
    Electronic Resource
    Electronic Resource
    Determination of laidlomycin and 26-deoxylaidlomycin by high-performance liquid chromatography (1991)
    Springer
    Chromatographia 31 (1991), S. 603-605 
    Details
    ISSN: 1612-1112
    Keywords: Column liquid chromatography ; Laidlomycin, 26-deoxylaidlomycin
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Summary High performance liquid chromatography on an octadecyl silica column has been used to determine laidlomycin: 26-deoxylaidlomycin ratios and to determine the concentration of both compounds by standard addition in samples prepared from fermentation broths ofStreptoverticillium olivoreticuli. A refractive index detector was preferred to an ultraviolet detector owing to the presence of UV-absorbing impurities which could not be completely separated from the substances of interest. Linear relationships were obtained from the calibration data. The coefficient of variation for the estimation of ratio and concentration of the compounds determined was better then 5%. The estimated limit of detection for both substances was about 50μg·ml−1.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF02279483
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 80
    Electronic Resource
    Electronic Resource
    Prediction of retention of O-ethyl, O-aryl and N-isopropyl phosphoroamidothioates in RP-HPLC from molecular structure parameters (1991)
    Springer
    Chromatographia 31 (1991), S. 143-146 
    Details
    ISSN: 1612-1112
    Keywords: Column liquid chromatography ; Molecular structure parameters ; Prediction of retention ; Phosphoroamidothiotes
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Summary Multi-variable regression analysis between lnkw, c (in retention equation lnk′=lnkw+cCb) and molecular structure parameters, including hydrophobicity, electric effect, field effect and position-specific effect constant, was carried out with O-ethyl, O-aryl and N-isopropyl phosphoroamidothioates as test solutes. With these quantitative relationships, the retention behaviour of these solutes for different mobile phase compositions was predicted. The results showed that there are only 26.7% of total, experimentally measured, capacity factors with relative deviations larger than 5% and only 2.2% with deviations larger than 10%, which means that it is possible to apply the method reported to predict retention values for qualitative purposes for different mobile phase compositions.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF02274562
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 81
    Electronic Resource
    Electronic Resource
    A method for the determination of histamine in wine by HPLC with precolumn derivatization with phenylisothiocyanate (1991)
    Springer
    Chromatographia 31 (1991), S. 133-136 
    Details
    ISSN: 1612-1112
    Keywords: Column liquid chromatography ; Histamine in wine ; Pre-column derivatization ; Solid phase extraction
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Summary A method for determining histamine in wine by precolumn derivatization with PITC (phenylisothiocyanate) with reversed-phase HPLC and UV detection is reported. Histamine can be determined together with the 24 amino acids within 40 min, or separately in a shorter time (less than 4 min) if a prior solid phase extraction clean-up is used.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF02274560
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 82
    Electronic Resource
    Electronic Resource
    Retention behavior of the inclusion complexes of some polycyclic aromatic hydrocarbons with β-cyclodextrin (1991)
    Springer
    Chromatographia 31 (1991), S. 157-162 
    Details
    ISSN: 1612-1112
    Keywords: Column liquid chromatography ; Cyclodextrin inclusion complexes ; Structure-retention relationships ; Polycyclic aromatics
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Summary The retention behaviour of a group of polycyclic aromatic hydrocarbons having nearly equal ionization potentials but different molecular polarizability values was investigated by reversed-phase HPLC and gas chromatography, using β-cyclodextrin as a selective inclusion reagent. In HPLC, the cyclodextrin was applied as an additive to the ethanolwater binary mobile phase, while in gas chromatography β-cyclodextrin served as the stationary phase coated on an inert support. The relationships between the capacity factors, molecular polarizabilities and the shape parameter of solute molecules is discussed.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF02274565
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 83
    Electronic Resource
    Electronic Resource
    Quantitation of cortico-steroids as common adulterants in local drugs by HPLC (1991)
    Springer
    Chromatographia 31 (1991), S. 67-70 
    Details
    ISSN: 1612-1112
    Keywords: Column liquid chromatography ; Cortico-steroids ; Drug adulterants
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Summary A sensitive and specific method for quantitation of the steroids betamethasone, prednisolone and cortisone acetate commonly used as adulterants in locally produced herb extracts and in certain homeopathic drugs is described. Reverse-phase liquid chromatography with UV detection has been used.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF02290499
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 84
    Electronic Resource
    Electronic Resource
    Chromatography of inorganic anions on poly(vinyl alcohol) gel columns with acidic eluents (1991)
    Springer
    Chromatographia 31 (1991), S. 80-84 
    Details
    ISSN: 1612-1112
    Keywords: Column liquid chromatography ; Ion chromatography ; Poly(vinyl alcohol) gel ; Inorganic anions ; UV detection for IC
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Summary Poly(vinyl alcohol) (PVA) gel shows ionic retention properties for common inorganic anions when an acidic eluent is used. The ionic property of the PVA gel is due to the proton-acceptable nitrogen atoms of the cross-linking agent and the carboxylic residues being comprised in the gel matrix. The extent of the net charge on the gel surface depends on the pH of the eluent. At a pH ranging from 2.3 to 5.3, the PVA gel behaves as a weak anion exchanger with very low ion-exchange capacity. At these conditions four UV-absorbing inorganic anions (bromate, bromide, nitrate, and nitrite) are separated by eluting with aqueous sulfuric acid. Alkyl groups introduced on the gel surface hinder the ionized solute molecules from accessing to the positively charged functional groups on the gel surface. A neutral solute (HNO2) is retained with non-ionic interactions.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF02290502
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 85
    Electronic Resource
    Electronic Resource
    Influence of injection conditions in reversed-phase high-performance liquid chromatography of chlorophylls and carotenoids (1991)
    Springer
    Chromatographia 31 (1991), S. 589-594 
    Details
    ISSN: 1612-1112
    Keywords: Column liquid chromatography ; Injection conditions ; Chlorophylls and carotenoids ; Extraction solvents ; Phytoplankton pigments
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Summary The RP-HPLC analysis of chlorophylls, their degradation products (chloropigments) and carotenoids is very sensitive to the nature of the injection solvent. The effect of sample-solvent interaction can result in the production of distorted, or even false, peaks that could be erroneously interpreted as “pigment like” or as poor chromatographic resolution. The previously suggested theoretical explantion, based on differences in solvent characteristics as expressed by the Polarity Index (P′) or even by the more precise solvent strength parameter for reversed-phase systems (S) we use, was unsatisfactory. The problem seems more complex, with other parameters such as injection volume and solute concentration or solvent selectivity also playing a role. As a practical consequence, however, suggesions are made for optimum injection conditions. Also, the presence of ion-pairing reagents in the injection solvent is demonstrated to be unnecessary.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF02279480
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 86
    Electronic Resource
    Electronic Resource
    The influence of end-capping on the enantioselectivity of a chiral phase (1991)
    Springer
    Chromatographia 31 (1991), S. 129-132 
    Details
    ISSN: 1612-1112
    Keywords: Column liquid chromatography ; End-capping ; Chiral stationary phase ; Enantioselectivity
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Summary The effect of end-capping chiral stationary phases (CSP's) derived fromN-(2-naphthyl)alanine undecyl ester has been examined using either trimethylchlorosilane (TMCS), hexamethyldisilazane (HMDS), or bis(trimethylsilyl) trifluoroacetamide (BSTFA) as end-capping reagents. The separation factor (α) and capacity factor (k′) of the enantiomers ofN-(3,5-dinitrobenzoyl)leucine octadecyl amide andN-(3,5-dinitrobenzoyl)alanine butyl ester were evaluated on three columns all packed with material from the same batch of stationary phase. These columns were essentially identical before, but not after end-capping with the above reagents. TMCS and HMDS were found to be superior to BSTFA, which appears to cause a significant loss of bonded phase from the silica surface. It seems that residual silanols affect the retention either by interacting with the analyte or by interacting with strands of stationary phase. End-capping usually increases enantioselectivity, sometimes by decreasing k′ for the first enantiomer and increasing k′ for the second enantiomer. The enhancement in enantioselectivity is greatest in relatively nonpolar mobile phases and occurs to a greater extent for phases having incomplete surface coverages.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF02274559
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 87
    Electronic Resource
    Electronic Resource
    Chromatographic characterization of a bonded liquid crystal stationary phase for HPLC (1991)
    Springer
    Chromatographia 31 (1991), S. 147-151 
    Details
    ISSN: 1612-1112
    Keywords: Column liquid chromatography ; Liquid crystal bonded phase ; Polycyclic aromatics ; Carvone and pulegone
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Summary A chromatographic and thermodynamic study of the compound [4-(allyloxy)benzoyl]-4-methoxyphenyl (ABMP) as a model of a chemically bonded liquid crystal stationary phase for HPLC was undertaken. A number of polycyclic aromatic hydrocarbons (PAHs) and two small solutes, carvone and pulegone, were studied under varying solvent and temperature conditions. Plots of log k′ vs. % organic in the mobile phase were not completely linear in all cases. The van't Hoff plots revealed at least one phase transition. The enthalpies of solute transfer from the mobile phase to the ABMP phase were determined for several PAHs. All tests indicate that ABMP possess liquid crystal properties when bonded to particulate silica.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF02274563
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 88
    Electronic Resource
    Electronic Resource
    Silica surface controversies, strong adsorption sites, their blockage and removal. Part II (1991)
    Springer
    Chromatographia 31 (1991), S. 193-205 
    Details
    ISSN: 1612-1112
    Keywords: Gas chromatography ; Column liquid chromatography ; Silanol adsorption centres ; Strongly interacting adsorption sites ; Suppression of adsorption activity
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Summary In this second part of the review heterogeneity of the silica surface is described and evidence is presented for the existence of a low population of strong adsorption sites. Methods of detection and determination of these strongly interacting sites are discussed. The last part of the review is devoted to the suppression of unwanted adsorption activity. Methods of blockage and special methods for the preparation of HPLC packings are described.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF02274571
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 89
    Electronic Resource
    Electronic Resource
    A rapid HPLC determination of narasin in fermentation broth (1991)
    Springer
    Chromatographia 31 (1991), S. 277-280 
    Details
    ISSN: 1612-1112
    Keywords: Column liquid chromatography ; Simplex optimization ; Narasin in fermentation broth ; Vanillin
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Summary A rapid HPLC assay with post-column derivatization has been developed for the determination of narasin in fermentation broth. The reaction of narasin with substituted benzaldehydes was investigated under first order conditions and the rate constants were determined for a variety of substituted benzaldehydes. Vanillin reacted most rapidly to produce a red color. The reaction conditions were optimized to acheive a maximum response with a minimum analysis time.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF02275750
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 90
    Electronic Resource
    Electronic Resource
    The effects of pH and alcoholic organic modifiers on the direct separation of some acidic, basic and neutral compounds on a commercially available ovomucoid column (1991)
    Springer
    Chromatographia 31 (1991), S. 329-334 
    Details
    ISSN: 1612-1112
    Keywords: Column liquid chromatography ; Ovomucoid stationary phase ; Chiral separations ; Mobile phase effects ; Protein conformation
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Summary The effects of alcoholic modifiers and pH on the chromatographic properties of an immobilized ovomucoid chiral stationary phase have been investigated using acidic, basic and neutral solutes. A series of primary, secondary and tertiary alcohols and pH's ranging from 3.5 to 6.0 were used in this study. The results indicate that both the shape and the hydrophobicity of the alcoholic modifier affect retention (k') and enantioselectivity (α). In general, an increase in the hydrophobicity of the modifier results in a decrease in k's and α's. However, this is not the case whent-butanol is the modifier, suggesting that the size of the alkyl moiety attached to the carbinol carbon also contributes to the chromatographic results. The pH studies indicated that Coulombic interactions play a role in the retention of the acidic and basic solutes. The results also suggest that in addition to ethanol and 1-propanol,t-butanol should be considered during optimization and that maximum efficiencies may be obtained at pH 5.0.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF02262187
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 91
    Electronic Resource
    Electronic Resource
    Influence of the mobile phase composition on the adsorption isotherms of an amino-acid derivative on immobilized bovine serum albumin (1991)
    Springer
    Chromatographia 31 (1991), S. 323-328 
    Details
    ISSN: 1612-1112
    Keywords: Column liquid chromatography ; Adsorption isotherms ; Immobilized serum albumen ; Chiral stationary phase ; Leucine, N-benzoyl derivative
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Summary The saturation capacity of columns packed with bovine serum albumin immobilized on silica has been determined for the N-benzoyl derivative of leucine at different compositions of a 1-propanol/water mobile phase. In all cases it has been found that the equilibrium adsorption data are well accounted for by a biLangmuir isotherm. The experimental data are consistent with the assumption that the column saturation capacity of the chiral selective sites as well as the saturation capacity of the non-selective sites are independent of the 1-propanol concentration in the range 0–10%.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF02262186
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 92
    Electronic Resource
    Electronic Resource
    New synthesis of alkyldihydrosilanes and their applications in modification of silica gel (1991)
    Springer
    Chromatographia 31 (1991), S. 335-341 
    Details
    ISSN: 1612-1112
    Keywords: Column liquid chromatography ; Bonded phase synthesis ; Alkyl and aryldimethyl phases ; CP/MAS NMR spectroscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Summary A comparison of newly synthesized, reversed-phase bonded stationary phases is presented. The materials studied include monomeric n-octyl, n-octadecyl, aryl and n-octyldihydrogeno bonded-phases. Differences in reactivity of the silane functional groups are demonstrated and the high coverage obtained with the hydrogeno-bonded phases is shown. The structures of the bonded phases have been determined by29Si and13C CP/MAS NMR spectroscopy.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF02262188
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 93
    Electronic Resource
    Electronic Resource
    Comparison of surface states of chemically modified silicas in aqueous acetonitrile and methanol (1991)
    Springer
    Chromatographia 31 (1991), S. 347-350 
    Details
    ISSN: 1612-1112
    Keywords: Column liquid chromatography ; Chemically modified silicas ; Surface states ; n-alkylbenzenes
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Summary The thermodynamic behaviour of n-alkylbenzenes on chemically modified silicas in reversed-phase liquid chromatography has been examined in acetonitrile-water and methanol-water systems. Plots of the thermodynamic parameters obtained against the organic solvent compositions indicate an interesting trend which implies that the surface states of the chemically modified silicas under the two eluent systems are different.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF02262190
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 94
    Electronic Resource
    Electronic Resource
    A particle size distribution analysis of stressed HPLC column packing material (1991)
    Springer
    Chromatographia 31 (1991), S. 362-366 
    Details
    ISSN: 1612-1112
    Keywords: Column liquid chromatography ; Particle size distribution ; Stationary phase stress ; Silica gel
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Summary A particle size distribution analysis has been completed on three different HPLC column packing materials including silica gel (Si60) and two bonded phases (RP8 and RP18). The stationary phases were subjected to 18 hours stress with 1 N or 3 N KOH and found to have quantitatively different distribution patterns initially, at 13 hours and finally at 18 hours although the average particle diameters for the Si60 and RP8 were the same or higher at 18 hours as initially. Thirteen hoursstress with sodium octanesulfonate, tetrabutylammonium phosphate and ammonium acetate at exaggerated conditions also resulted in distributional changes with the Si60 and RP8 decreasing in average particle diameter when exposed to ammonium acetate and tetrabutylammonium stressing respectively.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF02262193
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 95
    Electronic Resource
    Electronic Resource
    Separation of food-related biogenic amines by ion-interaction reversed-phase high performance liquid chromatography. Tyramine, histamine, 2-phenylethylamine, tryptamine and precursor aminoacids. Application to red wine (1991)
    Springer
    Chromatographia 31 (1991), S. 381-386 
    Details
    ISSN: 1612-1112
    Keywords: Column liquid chromatography ; Biogenic amines ; Wine ; Food-related biogenic amines
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Summary Methods for the separation of food-related biogenic amines (histamine, tyramine, 2-phenylethylamine and tryptamine) have been developed based on ion-interaction reversed-phase liquid chromatography. Two different interaction reagents have been comparatively used, namely octylamine ortho-phosphate (at wave-lengths of 230, 254 and 280 nm) and octylamine salicylate (at a wavelength of 254 nm). The different elution sequence orders shown by the investigated amines for the two reagents are discussed and compared. The detection limits obtained were 20 ppb for tryptamine (λ =280 nm), 500 ppb for 2-phenylethylamine (λ=254 nm), 400 ppb for tyramine (λ=230 or 280 nm) and 900 ppb for histamine (λ=230 nm). The method was applied to the analysis of a five years old Italian red wine, in which 2-phenylethylamine (at a concentration of 72±3 ppm) and tryptamine (at a concentration of 4.0±0.3 ppm) were found to be present.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF02262196
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 96
    Electronic Resource
    Electronic Resource
    Estimation of the degree of self-association of water using a novel retention model (1991)
    Springer
    Chromatographia 31 (1991), S. 387-392 
    Details
    ISSN: 1612-1112
    Keywords: Column liquid chromatography ; Retention model ; Self-association of water
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Summary An attempt has been made to gain a semi-quantitative insight into the self-association of water molecules through hydrogen bonds. This was only possible with the use of a new solute retention model for the chromatographic systems by considering intermolecular interactions between the constituents of binary mobile phases. Four different sizes of the average associative aqueous multimer were assumed. By comparing measured and calculated retention values, the existence of associated aqueous multimers consisting of 100 aqueous monomer units is postulated as an average multimer structure.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF02262197
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 97
    Electronic Resource
    Electronic Resource
    Analysis of nucleotides, nucleosides, nucleobases in cells by ion-pair reversed-phase HPLC (1991)
    Springer
    Chromatographia 31 (1991), S. 401-410 
    Details
    ISSN: 1612-1112
    Keywords: Column liquid chromatography ; Ion-pair reversed-phase separations ; Nucleotides ; Extraction from cells and tissue ; Retention mechanism
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Summary HPLC methods for the separation of nucleotides, nucleosides and nucleobases by ion-pair reversed-phase are reviewed. The advantages of these are discussed versus anion-exchange and reversed phase separations. Extraction procedures for nucleotide determinations from cells and tissues are pointed out in detail. Extracts from red blood cells, Ehrlich ascites tumour cells, hepatocytes, intestine are used for determination of nucleotide concentrations by the methods described.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF02262200
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 98
    Electronic Resource
    Electronic Resource
    Automated HPLC-amino acid determination of protein hydrolysates by precolumn derivatization with OPA and FMOC and comparison with classical ion exchange chromatography (1991)
    Springer
    Chromatographia 31 (1991), S. 441-447 
    Details
    ISSN: 1612-1112
    Keywords: Column liquid chromatography ; Ion exchange chromatography ; Quantitative amino acid analysis ; OPA/FMOC precolumn derivatization ; Cheese
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Summary An improved HPLC method for the quantitative determination of the amino acids from hydrolysed cheese proteins and peptides is described. Some important improvements to the existing method are suggested. The addition of piperidine-4-carboxylic acid (PICA) as a hydrolysis-resistant internal standard enabled the quantification of secondary amino acids. The following analytical parameters have been determined: repeatability, detection limit and linearity in the measuring range. A statistical comparison with the classical ion chromatographic method gave an excellent correlation for all determined amino acids. Both methods are free of artifacts and systematic errors. Compared with ion chromatography, HPLC shows the following advantages: faster equilibration of the column, shorter retention times, more stable baseline, narrower peaks and more sensitive fluorescence detection. A drawback is the slightly lower repeatability for some amino acids.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF02262386
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 99
    Electronic Resource
    Electronic Resource
    Chiral amino acid microanalysis by direct optical resolution of fluorescent derivatives on BSA-based (resolvosil) columns (1991)
    Springer
    Chromatographia 31 (1991), S. 429-433 
    Details
    ISSN: 1612-1112
    Keywords: Column liquid chromatography ; Chiral separations ; Amino acids ; Fluorogenic derivatization ; N-(Chloroformyl)-carbazole
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Summary A new reagent for fluorescence labelling of amino acids, N-(chloroformyl)-carbazole, has been used in order to achieve high sensitivity of detection as well as good optical resolution. The derivatization reaction is fast and conveniently carried out at room temperature by shaking a buffered aqueous solution of the amino acids with an acetone solution of the reagent. The individual derivatized amino acids are first separated and collected via chromatography on a standard octadecyl-silica column. Each amino acid derivative is then analyzed for enantiomer composition by re-injection on a BSA-silica (Resolvosil®) column using fluorescence detection. For some amino acids (alanine, threonine, phenylalanine, tryptophan) enantiomeric separation factors exceeding α=3 have been obtained. The phosphonic acid analogue of alanine (1-aminoethylphosphonic acid) was also found to be well resolved into its enantiomers.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF02262384
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 100
    Electronic Resource
    Electronic Resource
    Analysis of catechins and proanthocyanidins in grape seeds by HPLC with photodiode array detection (1991)
    Springer
    Chromatographia 31 (1991), S. 465-468 
    Details
    ISSN: 1612-1112
    Keywords: Column liquid chromatography ; Catechins ; Grape seeds ; Proanthocyanidins ; UV-visible spectroscopy/diode array detection
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Summary Reversed-phase, high-performance liquid chromatography coupled to photodiode array detection has been used to analyse catechins and proanthocyanidins extracted from grape seeds. Results show that the ethyl acetate fraction obtained by passing extracts of samples adjusted to pH 7.0 through preconditioned C18 SEP-PAK cartridges contains several catechins and proanthocyanidins. Seven peaks have been assigned to standard catechins and proanthocyanidins on the basis of their retention times and UV spectra. Other peaks which appear in the chromatogram show spectral behaviour similar to that of standard catechins and proanthocyanidins.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF02262390
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...