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
  • Chemistry  (9)
  • Condensed Matter: Electronic Properties, etc.  (2)
  • Imines  (2)
  • Nicotiana  (2)
  • galactokinase
  • 2010-2014  (2)
  • 1990-1994  (11)
  • 1965-1969  (2)
  • 1
    Electronic Resource
    Electronic Resource
    Normal expression of thymidine kinase and O6-methylguanine-DNA methyltransferase in cultured fibroblasts from individuals with hereditary galactokinase deficiency (1991)
    Springer
    Biochemical genetics 29 (1991), S. 135-144 
    Details
    ISSN: 1573-4927
    Keywords: galactokinase ; thymidine kinase ; O6-methylguanine-DNA methyltransferase ; gene regulation
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Chemistry and Pharmacology
    Notes: Abstract Expression of the enzymes galactokinase, thymidine kinase, and O6-methylguanine-DNA methyltransferase is occasionally coordinately regulated in human cell lines. We have measured the activities of these three enzymes in extracts of fibroblasts from individuals with hereditary galactokinase deficiency. These cells do not express measurable galactokinase activity. The levels of O6-methylguanine-DNA methyltransferase were in the normal range in cells from three galactokinase-deficient individuals. The activity of thymidine kinase in the affected cells was in the normal range for two of the three individuals. The reduced thymidine kinase activity in the third individual reflected the extremely poor growth of the cells in culture. Immortalization of one galactokinase-deficient cell line resulted in loss of O6-methylguanine-DNA methyltransferase activity, but the galactokinase and thymidine kinase levels remained unchanged. The data indicate that the loss of galactokinase activity in these individuals is the consequence of an alteration of gene expression which does not involve coordinate silencing with the thymidine kinase and methyltransferase loci.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00554207
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 2
    Electronic Resource
    Electronic Resource
    Normal expression of thymidine kinase and O6-methylguanine-DNA methyltransferase in cultured fibroblasts from individuals with hereditary galactokinase deficiency (1991)
    Springer
    Biochemical genetics 29 (1991), S. 135-144 
    Details
    ISSN: 1573-4927
    Keywords: galactokinase ; thymidine kinase ; O6-methylguanine-DNA methyltransferase ; gene regulation
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Chemistry and Pharmacology
    Notes: Abstract Expression of the enzymes galactokinase, thymidine kinase, and O6-methylguanine-DNA methyltransferase is occasionally coordinately regulated in human cell lines. We have measured the activities of these three enzymes in extracts of fibroblasts from individuals with hereditary galactokinase deficiency. These cells do not express measurable galactokinase activity. The levels of O6-methylguanine-DNA methyltransferase were in the normal range in cells from three galactokinase-deficient individuals. The activity of thymidine kinase in the affected cells was in the normal range for two of the three individuals. The reduced thymidine kinase activity in the third individual reflected the extremely poor growth of the cells in culture. Immortalization of one galactokinase-deficient cell line resulted in loss of O6-methylguanine-DNA methyltransferase activity, but the galactokinase and thymidine kinase levels remained unchanged. The data indicate that the loss of galactokinase activity in these individuals is the consequence of an alteration of gene expression which does not involve coordinate silencing with the thymidine kinase and methyltransferase loci.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF02401808
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 3
    Electronic Resource
    Electronic Resource
    Leaf surface chemicals fromNicotiana affecting germination ofPeronospora tabacina (adam) sporangia (1992)
    Springer
    Journal of chemical ecology 18 (1992), S. 1467-1479 
    Details
    ISSN: 1573-1561
    Keywords: Nicotiana ; Peronospora tabacina ; blue mold ; leaf surface ; chemistry ; diterpenes ; sugar esters
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Chemistry and Pharmacology
    Notes: Abstract A bioassay was used to evaluate the effects of cuticular leaf components, isolated fromN. tabacum, N. glutinosa (accessions 24 and 24a), and 23other Nicotiana species, on germinationof P. tabacina (blue mold). The leaf surface compounds includedα- andβ-4,8,13,-duvatriene-l,3-diols (DVT-diols), (13-E)-labda-13-ene-8α-,15-diol (labdenediol), (12-Z)-labda-12,14-diene-8α-ol (cis-abienol), (13-R)-labda-8,14-diene-13-ol (manool), 2-hydroxymanool, a mixture of (13-R)-labda-14-ene-8α,13-diol (sclareol), and (13-S)-labda-14-ene-8α,13-diol (episclareol), and various glucose and/or sucrose ester isolates. The above in acetone were applied onto leaf disks of the blue moldsusceptibleN. tabacum cv. TI 1406, which was then inoculated with blue mold sporangia. Estimated IC50 values (inhibitory concentration) were 3.0μg/cm2 forα-DVT-diol, 2.9μ/cm2 forβ-DVT-diol, 0.4μg/cm2 for labdenediol and 4.7μg/cm2 for the sclareol mixture. Manool, 2-hydroxymanool, andcis-abienol at application rates up to 30μg/cm2 had little or no effect on sporangium germination. Glucose and/or sucrose ester isolates from the cuticular leaf extracts of 23Nicotiana species and three different fractions fromN. bigelovii were also evaluated for antimicrobial activity at a concentration of 30μg/cm2. Germination was inhibited by 〉20% when exposed to sugar esters isolated fromN. acuminata, N. benthamiana, N. attenuata, N. clevelandii, andN. miersii, and accessions 10 and 12 ofN. bigelovii. These results imply that a number of compounds may influence resistance to blue mold in tobacco.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00993221
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 4
    Electronic Resource
    Electronic Resource
    (E,Z) Equilibria, 14. Substituent-Induced Chemical Shifts along the C = N Bond of Schiff Bases (1992)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 125 (1992), S. 2033-2040 
    Details
    ISSN: 0009-2940
    Keywords: 13C NMR, SCS ; Substituent effects ; Imines ; Isomerization, (E,Z) Schiff bases ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Sterically congested N-(1,1,3,3-tetraalkyl-2-indanylidene)-amines 8-11, N-(cyclopentylidene)anilines 13-17, and two of their salts are described, together with a short synthesis of 2-imino-1,1,3,3-tetramethylindan (5). Some of these imines show rapid (E,Z) equilibration. Positively and negatively charged nitrogen functions (in 6 and 7) cause opposite 1H- and 13C-NMR chemical shift effects along the C = N bond. Chemical shifts are almost equally affected by the lone electron pair and by the imino N-H bond. Substituent-induced chemical shifts (SCS) have been assigned for all syn and anti positions with respect to methyl, phenyl, and 2,6-dimethylphenyl groups at the imino nitrogen atom. The structurally well-defined, rigid imines recommend themselves as new models for the calibration of theoretical approaches to syn/anti-differentiating SCS.
    Additional Material: 3 Tab.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19921250911
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 5
    Electronic Resource
    Electronic Resource
    (E, Z)1-Equilibria, 17 Demonstration of the Nitrogen Inversion Mechanism of Imines in a Schiff Base ModelDedicated to Professor Heinrich Nöth on the occasion of his 65th birthday. (1993)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 126 (1993), S. 747-754 
    Details
    ISSN: 0009-2940
    Keywords: Diastereotopomerization, (E, Z) ; Imines ; Inversion, nitrogen ; Permethylation ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Experimental differentiation between pure C=N double bond rotation and nitrogen inversion in N1-arylimines is possible with a single compound (13b) under the proviso of slow rotation about the N-aryl single bond. Labelling by 1H and 13C nuclei at the diastereotopic faces of the C=N moiety as well as of the N-aryl group is the clue to a successful stereodynamic analysis, as performed by variable-temperature NMR spectroscopy of 13b, a sterically congested and chiral model compound. Interpretation of similar measurements on a second model (13d) is less straightforward. The experimental observation of time-averaged Cs symmetry by NMR coalescences is only compatible with a mechanism of (E/Z) stereomutation either by pure inversion at sp2 nitrogen or by a contribution from C=N rotation together with a synchronized (geared) controtation about the N-aryl single bond. However, the latter combination is concluded to be predominantly inversion-like by comparisons with related imines.
    Additional Material: 1 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19931260327
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 6
    Electronic Resource
    Electronic Resource
    Ovipositional response of tobacco budworm moths (Lepidoptera: Noctuidae) to cuticular labdanes and sucrose esters from the green leaves ofNicotiana glutinosa L. (Solanaceae) (1991)
    Springer
    Journal of chemical ecology 17 (1991), S. 2489-2506 
    Details
    ISSN: 1573-1561
    Keywords: Insecta ; Lepidoptera ; Noctuidae ; Heliothis virescens ; tobacco budworm ; Nicotiana ; ovipositional stimulants
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Chemistry and Pharmacology
    Notes: Abstract Field plots of three accessions ofNicotiana glutinosa L. (Nicotiana species accessions 24, 24A, and 24B) at Oxford, North Carolina and Tifton, Georgia were heavily damaged by natural populations of tobacco budworms,Heliothis virescens (F.), during 1985–1989. Experiments in outdoor screen cages demonstrated that all accessions ofN. glutinosa were as prone to oviposition byH. virescens moths as was NC 2326, a commercial cultivar of flue-cured tobacco,N. tabacum L. However, in greenhouse experiments, tobacco budworm larvae did not survive or grow as well when placed on plants ofN. glutinosa as they did when placed on plants of NC 2326. Four labdane diterpenes (manool, 2-hydroxymanool, a mixture of sclareols, and labda-13-ene-8α,15-diol [labdenediol]) and two sucrose ester fractions (2,3,4-tri-O-acyl-3′-O-acetyl-sucrose [G-SE-I] and 2,3,4,-tri-O-acyl-sucrose [G-SE-II]) were isolated from green leaves of the three accessions ofN. glutinosa. These components were bioassayed for their effects on the ovipositional behavior of tobacco budworm moths using small screen cages in a greenhouse at Oxford, North Carolina. Labdenediol, manool, and both sucrose ester fractions stimulated tobacco budworm moths to oviposit on a tobacco budworm-resistant Tobacco Introduction, TI 1112 (PI 124166), when these materials were sprayed onto a leaf.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00994597
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 7
    Electronic Resource
    Electronic Resource
    Expression of recombinant protein A from the lac promoter in Escherichia coli JM83 is not subject to catabolite repression when grown under specific conditions of continuous culture (1991)
    New York, NY [u.a.] : Wiley-Blackwell
    Biotechnology and Bioengineering 38 (1991), S. 1050-1058 
    Details
    ISSN: 0006-3592
    Keywords: catabolite repression ; protein A ; membrane proteins ; continuous culture ; protein expression ; Chemistry ; Biochemistry and Biotechnology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: Although widely used in experimental and industrial situations, genetically engineered plasmids containing the lac promoter from Escherichia coli are subject to catabolite repression when grown in glucose-containing media. Several methods of overcoming this problem have been investigated by studying the expression of the protein A gene from Staphylococcus aureus under the control of the Escherichia coli lac promoter. When glycerol is used as a sole carbon source, the plasmid is unstable and is rapidly lost from the culture. When the bacteria are grown in chemostats under glucose limitation, the plasmid is maintained, even at high dilution rates, and the expression of protein A is similar to that observed when glycerol was used. The balance between metabolic load and protein A expression seems to be maintained by reducing the gene dose to a tolerable level. Depending on the metabolic conditions prevailing in the culture, this is achieved, either by reducing the copy number of the plasmid or in extreme cases by removing the plasmid altogether.
    Additional Material: 10 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/bit.260380914
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 8
    Electronic Resource
    Electronic Resource
    Mass spectra of trimethylsilyl derivatives of naturally occurring flavonoid aglycones and chalcones (1991)
    Chichester : Wiley-Blackwell
    Biological Mass Spectrometry 26 (1991), S. 157-160 
    Details
    ISSN: 0030-493X
    Keywords: Chemistry ; Analytical Chemistry and Spectroscopy
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Electron impact mass spectra of the trimethylsilyl derivatives of a series of flavonoid aglycones and chalcones are reported. The spectra show prominent ions arising from fragmentation of the trimethylsilyl (TMS) groups. Inter-actions between adjacent TMS groups, and between TMS groups in the 3- or 5-position (6′-position for the chalcones) and the C-ring carbonyl, yield structurally significant ions. Few fragments associated with the retro-Diels-Alder cleavage of the C-ring characteristic of the underivatized compounds, are observed. The TMS derivatives thus provide complementary information for the identification of flavonoid aglycones and chalcones in biological systems.
    Additional Material: 1 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/oms.1210260310
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 9
    Electronic Resource
    Electronic Resource
    A fast x-ray counting system (1993)
    New York, NY [u.a.] : Wiley-Blackwell
    X-Ray Spectrometry 22 (1993), S. 58-60 
    Details
    ISSN: 0049-8246
    Keywords: Chemistry ; Analytical Chemistry and Spectroscopy
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Physics
    Notes: An unusually fast x-ray detector and pulse processing counting system has been devised and tested. The overall dead time of the system was determined experimentally to be 42 ns.
    Additional Material: 1 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/xrs.1300220113
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 10
    Electronic Resource
    Electronic Resource
    Substituent-induced chemical shifts (SCS) by the phenyl group in sterically congested styrene derivativesSterically Congested Molecules, Part 7. For Part 6, see R. Knorr et al., Chem. Ber. 126, in press (1993). (1993)
    Chichester : Wiley-Blackwell
    Organic Magnetic Resonance 31 (1993), S. 388-393 
    Details
    ISSN: 0749-1581
    Keywords: 13C NMR ; 1H NMR ; 9-Methylenefluorenes ; Substituent effects ; Substituent-induced chemical shifts ; Chemistry ; Analytical Chemistry and Spectroscopy
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The two 13C NMR methyl signals of the sterically congested 9-benzylidene-1,8-dimethylfluorene (1a) have the surprisingly small separation of only 0.37 ppm; for 9-benzylidene-2,7-dimethylfluorene the corresponding methyl separation is 0.04 ppm. An alternative analysis of 1a with respect to 1,8-dimethylfluorene shows that the perturbing syn-phenyl substituent has caused a downfield ( + 0.47 ppm) 13C shift but an upfield 1H shift ( - 0.97 ppm) of the compressed 1-CH3 group. For further comparisons, NMR assignments were also made for 2,7-dimethylfluorene, 1,8-dimethylfluoren-9-one and 2-(1,1-dimethylethyl)-3,3-dimethyl-1-phenylbut-1-ene.
    Additional Material: 2 Tab.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/mrc.1260310415
    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...