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1.
A.K. Overgaard J. Friis L. Christensen H. Christiansen L. Rasmussen 《FEMS microbiology letters》1995,132(1-2):159-163
Abstract Saccharomyces cerevisiae was inoculated into a yeast nitrogen base with either glycerol or glucose as carbon source. Cell proliferation was followed by colony counts on agar medium. Cells in the glycerol-supplemented medium divided less than once in 10 days. When glucose, 6-deoxy-glucose or protoporphyrin IX was added, the cells had doubling times of about 24 h and increased in number to about 0.5 × 106 cells ml−1 Addition of either of the protein kinase C activators oleoyl-acetylglycerol or phorbol-12-myristate-13-acetate did not activate cell proliferation in the glycerol medium. However, when (i) glucose was combined with either protoporphyrin IX or chlorophyllin, or (ii) either protoporphyrin IX or chlorophyllin was combined with either of the protein kinase C activators, the cells had doubling times of about 12 h. Hence, (i) glucose can act as both a carbon source and a signalling molecule for proliferation, and (ii) two systems are involved in activating cell proliferation in S. cerevisiae : one operating through a protein kinase C system and another through a guanylate cyclase system. 相似文献
2.
Molecular and immunological characterization of the major outer membrane proteins of Brucella 总被引:2,自引:0,他引:2
Axel Cloeckaert Jean-Michel Verger Maggy Grayon Nieves Vizcaíno 《FEMS microbiology letters》1996,145(1):1-8
Abstract Saccharomyces cerevisiae exponentially growing in basic or 0.7 M NaCl medium were isotopically labelled with 35 S-methionine, followed by protein separation and quantification by two-dimensional polyacrylamide gel electrophoresis (2D-PAGE) combined with computerised image analysis. The electrophoretic separation resolved about 650 proteins of which 13 displayed significant and at least 2-fold changes in rate of synthesis during saline growth. By sequencing of 2D-PAGE resolved proteins, one of the 8 induced spot, p42.9/5.5, was shown to correspond to the full length (containing the N-terminal extension) product of the GPD 1 gene encoding the cytoplasmic glycerol 3-phosphate dehydrogenase. The expression of the TDH 3 gene, glyceraldehyde 3-phosphate dehydrogenase, and the ENO 2 gene, enolase, decreased during growth in NaCl medium, declines hypothesised to have an impact on the flux to glycerol. 相似文献
3.
4.
Two Saccharomyces cerevisiae strains with different degrees of ethanol tolerance adapted differently to produced ethanol. Adaptation in the less ethanol-tolerant
strain was high and resulted in a reduced formation of ethanol-induced respiratory deficient mutants and an increased ergosterol
content of the cells. Adaptation in the more ethanol-tolerant strain was less pronounced. Journal of Industrial Microbiology & Biotechnology (2000) 24, 75–78.
Received 22 June 1999/ Accepted in revised form 06 October 1999 相似文献
5.
K. S. Karthikeyan H. Polasa K. Sivarama Sastry Gopal Reddy 《Indian journal of microbiology》2008,48(3):397-400
Saccharomyces cerevisiae which cannot utilize lysine as a sole nitrogen source is shown to metabolize a Lysine 3 Cr3+ (1:1) complex synthesized, as a combined nitrogen and carbon source. It induces rapid uptake of lysine and prevents loss
of viability, in contrast with free lysine. That complexation with trivalent chromium has the effect of profoundly influencing
intracellular distribution and metabolism of the liganded amino acid is demonstrated. 相似文献
6.
Karl-D. Entian Kai-U. Fröhlich Dieter Mecke 《Biochimica et Biophysica Acta (BBA)/General Subjects》1984,799(2):181-186
An electrophoretic method has been devised to investigate the changes in the enzymes and isoenzymes of carbohydrate metabolism, upon adding glucose to derepressed yeast cell. (i) Of the glycolytic enzymes tested, enolase II, pyruvate kinase and pyruvate decarboxylase were markedly increased. This increase was accompanied by an overall increase in glycolytic activity and was prevented by cycloheximide, an inhibitor of protein synthesis. (ii) In contrast, respiratory activity decreased after adding glucose. This decrease was clearly shown to be the result of repression of respiratory enzymes. A rapid decrease within a few minutes of adding glucose, by analogy with the so-called ‘Crabtree effect’, was not observed in yeast. (iii) The gluconeogenic enzymes, fructose-1,6-bisphosphatase and malate dehydrogenase, which are inactivated after adding glucose, showed no significant changes in electrophoretic mobilities. Hence, there was no evidence of enzyme modifications, which were postulated as initiating degradation. However, it was possible to investigate cytoplasmic and mitochondrial malate dehydrogenase isoenzymes separately. Synthesis of the mitochondrial isoenzyme was repressed, whereas only cytoplasmic malate hydrogenase was subject to glucose inactivation. 相似文献
7.
One of the important factors affecting wine fermentation is temperature. The influence of elevated temperatures from 10 to
25 °C at 5 °C intervals on yeast growth and fermentation products were studied in mixed cultures of Kloeckera apiculata and Saccharomyces cerevisiae in grape juice. In the experiments carried out at 10 and 15 °C, K. apiculata grew and survived longer compared to trials conducted above 20 °C. In most cases, higher temperatures stimulated the production
of higher alcohols but lowered the formation of esters and acetaldehyde.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
8.
Shiro Tabata Takeshi Ide Yasuyoshi Umemura Kenzo Torri 《Biochimica et Biophysica Acta (BBA)/General Subjects》1984,797(2):231-238
α-Glucosidases or maltases (EC 3.2.1.20) were purified to electrophoretic homogeneity from a respective strain of Sacchromyces cerevisiae which carries a single MAL gene, either MALα, MALβ or MALγ, using gluconate-Sepharose affinity chromography and isoelectrofocusing. Of these maltases, two types of maltase were obtained from the MALγ strain, the pI values of which were 5.6 and 5.9. From the MALα and MALβ strain was obtained only one type of maltase with the pI at 5.6 which was identical to one of the maltases from the MALγ strain. These four maltases possessed the same properties, except for pI. They were monomers with molecular weights of between 66 000 and 67 000. With regard to the substrate specificity, they hydrolyzed maltose and sucrose exclusively but not α-methulglucoside nor maltooligosaccharide. They did not differ in immunological properties. 相似文献
9.
10.
David M. Mueller 《Journal of bioenergetics and biomembranes》2000,32(4):391-400
The mitochondrial ATP synthase is a molecular motor that drives the phosphorylation ofADP to ATP. The yeast mitochondrial ATP synthase is composed of at least 19 differentpeptides, which comprise the F1 catalytic domain, the F0 proton pore, and two stalks, oneof which is thought to act as a stator to link and hold F1 to F0, and the other as a rotor.Genetic studies using yeast Saccharomyces cerevisiae have suggested the hypothesis thatthe yeast mitochondrial ATP synthase can be assembled in the absence of 1, and even 2, ofthe polypeptides that are thought to comprise the rotor. However, the enzyme complexassembled in the absence of the rotor is thought to be uncoupled, allowing protons to freelyflow through F0 into the mitochondrial matrix. Left uncontrolled, this is a lethal process andthe cell must eliminate this leak if it is to survive. In yeast, the cell is thought to lose ordelete its mitochondrial DNA (the petite mutation) thereby eliminating the genes encodingessential components of F0. Recent biochemical studies in yeast, and prior studies in E. coli,have provided support for the assembly of a partial ATP synthase in which the ATP synthaseis no longer coupled to proton translocation. 相似文献