ALBERT

All Library Books, journals and Electronic Records Telegrafenberg

feed icon rss

Your email was sent successfully. Check your inbox.

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

Proceed reservation?

Export
  • 1
    Electronic Resource
    Electronic Resource
    Springer
    Archives of microbiology 113 (1977), S. 303-307 
    ISSN: 1432-072X
    Keywords: Saccharomyces cerevisiae ; Specific growth rate ; Growth control ; Glucose transfer ; Glucose-6-phosphate ; Maintenance requirements
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract The specific growth rate (μ) of a respiration-deficient mutant of Saccharomyces cerevisiae growing under defined experimental conditions in batch culture (mineral medium plus glucose and vitamins at 25°C) varied from experiment to experiment over a wide range (0.10–0.24 h-1) and showed a normal distribution. Neither the age of the culture, the history of the inoculum, nor experimental error accounted wholy for the variability of μ. The variation was positively correlated with the specific rate of glucose transfer and negatively with the specific rate of production of non-fermentative CO2. The yield decreased with μ implying higher maintenance requirements in batch culture (4.7 mmoles g-1 h-1) than in continuous culture (0.8 mmoles g-1 h-1). It was concluded that the strain is capable of establishing any one of several steady states of growth under the same experimental conditions, each steady state displaying some buildin inertia with respect to change. The variations of the specific rates of glucose transfer and non-fermentative CO2 production, and of the yield appeared to be consequences rather than causes of the variation of μ. The ultimate causes of the variation of μ remained unidentified.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 2
    ISSN: 1573-4919
    Keywords: glutathione reductase ; Saccharomyces cerevisiae ; redox interconversion ; metals ; cell-free extracts
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Chemistry and Pharmacology , Medicine
    Notes: Summary Redox inactivation of glutathione reductase involves metal cations, since chelators protected against NADPH-inactivation, 3 µM EDTA or 10 µM DETAPAC yielding full protection. Ag+, Zn2+ and Cd2+ potentiated the redox inactivation promoted by NADPH alone, while Cr3+, Fe2+, Fe3+, Cu+, and Cu2+ protected the enzyme. The Zn2+ and Cd2+ effect was time-dependent, unlike conventional inhibition. Glutathione reductase interconversion did not require dioxygen, excluding participation of active oxygen species produced by NADPH and metal cations. One Zn2+ ion was required per enzyme subunit to yield full NADPH-inactivation, the enzyme being reactivated by EDTA. Redox inactivation of glutathione reductase could arise from the blocking of the dithiol formed at the active site of the reduced enzyme by metal cations, like Zn2+ or Cd2+. The glutathione reductase activity of yeast cell-free extracts was rapidly inactivated by low NADPH or moderate NADH concentrations; NADP+ also promoted rapid inactivation in fresh extracts, probably after reduction to NADPH. Full inactivation was obtained in cell-free extracts incubated with glucose-6-phosphate or 6-phosphogluconate; the inactivating efficiency of several oxidizable substrates was directly proportional to the specific activities of the corresponding dehydrogenases, confirming that redox inactivation derives from NADPH formed in vitro.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 3
    Electronic Resource
    Electronic Resource
    Springer
    Molecular genetics and genomics 217 (1989), S. 464-470 
    ISSN: 1617-4623
    Keywords: Nucleosome positioning ; LEU2 gene ; Saccharomyces cerevisiae ; tRNA3 Leu gene ; Chromatin
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary The chromatin structure of theLEU2 gene and its flanks has been studied by means of nuclease digestion, both with micrococcal nuclease and DNase I. The gene is organized in an array of positioned nucleosomes. Within the promoter region, the nucleosome positioning places the regulatory sequences, putative TATA box and upstream activator sequence outside the nucleosomal cores. The tRNA3 Leu gene possesses a characteristic structure and is protected against nucleases. Most of the 5′ flank is sensitive to DNase I digestion, although no clear hypersensitive sites were found. The chromatin structure is independent of either the transcriptional state of the gene or the chromosomal or episomal location. Finally, in the plasmid pJDB207, which lacks most of the promoter, we have found that the chromatin structure of the coding region is similar to that of the wild-type allele.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 4
    Electronic Resource
    Electronic Resource
    Springer
    Molecular genetics and genomics 258 (1998), S. 628-638 
    ISSN: 1617-4623
    Keywords: Key words Phosphate transport ; PHO89 ; Saccharomyces cerevisiae
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Based on the high sequence homology between the yeast ORF YBR296c (accession number P38361 in the SWISS-PROT database) and the PHO4 gene of Neurospora crassa, which codes for a Na+/Pi cotransporter with twelve putative transmembrane domains, the YBR296c ORF was considered to be a promising candidate gene for a plasma membrane-bound phosphate transporter in Saccharomyces cerevisiae. Therefore, this gene, here designated PHO89, was cloned and a set of deletion mutants was constructed. We then studied their Pi uptake activity under different conditions. We show here that a transport activity displayed by PHO89 strains under alkaline conditions and in the presence of Na+ is absent in pho89 null mutants. Moreover, when the pH was lowered to pH 4.5 or when Na+ was omitted, this activity decreased significantly, reaching values close to those exhibited by the Δpho89 mutant. Studies of the acid phosphatase activity of these strains, as well as promoter sequence analysis, suggest that expression of the PHO89 gene is under the control of the PHO regulatory system. Northern analysis shows that this gene is only transcribed under conditions of Pi limitation. This is, to our knowledge, the first demonstration that the PHO89 gene codes for the Na+/Pi cotransporter previously characterized by kinetic studies, and represents the only Na+-coupled secondary anion transport system so far identified in S. cerevisiae. Pho89p has been shown to have an apparent Km of 0.5 μM and a pH optimum of 9.5, and is highly specific for Na+; activation of transport is maximal at a Na+ concentration of 25 mM.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 5
    ISSN: 1617-4623
    Keywords: Saccharomyces cerevisiae ; Lysyl-tRNA synthetase ; PMR2 repeat ; Genome organization
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary TheKRS1 gene encodes the cytoplasmic form ofSaccharomyces cerevisiae lysyl-tRNA synthetase. TheKRS1 locus has been characterized. The lysyl-tRNA synthetase gene is unique in the yeast genome. The gene is located on the right arm of chromosome IV and disruption of the open reading frame leads to lethality. These results contrast with the situation encountered inEscherichia coli where lysyl-tRNA synthetase is coded by two distinct genes,lysS andlysU, and further address the possible biological significance of this gene duplication. The nucleotide sequence of the 3′-flanking region has been established. It encodes a long open reading frame whose nucleotide and amino acid structures are almost identical toPMR2, a cluster of tandemly repeated genes coding for P-type ion pumps. The sequence alterations relative toPMR2 are mainly located at the C-terminus of the protein.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...