摘要:

AbstractVanadium metabolism was studied in a wild type and respiratory‐deficient strains ofS. cerevisiae.Inhibition of growth by vanadate [V(+5)], vanadate accumulation, and conversion of medium vanadate [V(+5)]to both cell‐associated and medium vanadyl [V(+4)] and vanadate [V(+5)]were compared. The growth of both the parental and respiratory‐deficient strains was inhibited by vanadate at concentrations greater than or equal to 1 mM. Both parental and respiratory‐deficient strains accumulated vanadate and converted medium vanadate to cellular vanadyl as detected using electron spin resonance (ESR). The accumulation of cell‐associated vanadyl was correlated with the loss of medium vanadate in both strains using a chemical assay. In contrast, the respiratory‐deficient strain showed a greater amount of a cell‐associated vanadate compound, as detected with vanadium‐51 nuclear magnetic resonance (51V‐NMR), than the wild strain or a representative respiratory‐competent vanadate‐resistant mutant. These data imply that mitochondrial function may be directly involved i

ISSN:0749-503X    

DOI:10.1002/yea.320020202

出版商:John Wiley&Sons, Ltd.    

年代:1986

数据来源: WILEY

摘要:

AbstractUnder conditions known to separate methylamine oxidase from benzylamine oxidase in other yeast strains, only a single oxidase could be detected inSporobolomyces albo‐rubescens.This occurred irrespective of whether methylamine orn‐butylamine was the nitrogen source for growth. The oxidase did not attack benzylamine. It was concluded that this organism can only produce a methylamine oxidase. The enzyme was purified to 90% homogeneity and found to have properties significantly a methylamine oxidases previously characterised. It lost only 40% of its activity in 30 min at 45°C, whereas methylamine oxidase previously described had half‐lives of from 2 to 9 min at 45°C. It showed also a lower activity with short chain 1‐aminoalkanes and a higher activity with longer chain 1‐aminoalkanes than other methylamine oxidases, and had a significantly smaller subunit molecular weight (57 000 compared w

ISSN:0749-503X    

DOI:10.1002/yea.320020203

出版商:John Wiley&Sons, Ltd.    

年代:1986

数据来源: WILEY

摘要:

AbstractIn completely randomised factorial experiments, individual and synergistic effects of pH, benzoic acid and sorbic acid on the growth rate of the yeastZygosaccharomyes bailiiwere determined, and expressed in polynomial equations. Synergism between benzoic and sorbic acid was pH dependent. A distinct effect of the anionic form of benzoic acid on doubling time was demonstrated by experiments in which concentrations of benzoic acid and benzoate were varied. The resultant polynomial equation showed that both species act synergistically.

ISSN:0749-503X    

DOI:10.1002/yea.320020204

出版商:John Wiley&Sons, Ltd.    

年代:1986

数据来源: WILEY

摘要:

AbstractIn a previous paper (Cármeneset al., 1984) we reported that UDP‐glucose 4‐epimerase fromSaccharomyceswas inactivated bothin vitro(Crude extracts) byL‐arabinose orD‐xylose. In this paper, we reported that pure epimerase requires the presence of UMP or UDP to be inactivated by sugars and that the inactivation is due to the reduction of the epimerase NAD+, which is essential for epimerase activity. The inactivation rate is directly proportional to epimerase and sugar concentrations and hyperbolically proportional to UMP concentration.In situexperiments made with permeabilized cells showed that epimerase is inactivated in the same way when it is inside the cell.In vivostudies showed that epimerase is inactivated to a smaller extent when 1%Dgalactose is present in the culture medium than when 1% ethanol is the main carbo

ISSN:0749-503X    

DOI:10.1002/yea.320020205

出版商:John Wiley&Sons, Ltd.    

年代:1986

数据来源: WILEY

ISSN:0749-503X    

DOI:10.1002/yea.320020206

出版商:John Wiley&Sons, Ltd.    

年代:1986

数据来源: WILEY

摘要:

AbstractA comparative radiorespirometric study of glucos emetabolism in glucose‐limited chemostat cultures ofSaccharomyces cerevisiae, Candida utilisandRhodosporidium toruloideswas performed in an attempt to estimate the contribution of the hexose monophosphate (HMP) pathway to glucose metabolism. Radioactively labelled glucose was administered directly to the cultures in a constant substrate feed, without disturbance of the steady state. The14CO2yields from [1‐14C]‐ and [6‐14C]‐glucose demonstrated that the HMP pathway activities for the three yeasts were very similar. Furthermore, a quantitative analysis of results indicated that the HMP pathway activities were close to the theoretical minimum needed to cover the NADPH requirement for biomass

ISSN:0749-503X    

DOI:10.1002/yea.320020207

出版商:John Wiley&Sons, Ltd.    

年代:1986

数据来源: WILEY

摘要:

AbstractAll type strains of ‘non‐fermentative’ yeasts, available in the culture collection of the Centraalbureau voor Schimmelcultures, were reinvestigated for their capacity to ferment glucose in the classical Durham tube test. Although visible gas production was absent, nearly all strains produced significant amounts of ethanol under the test conditions. Under conditions of oxygen‐limited growth, even strong alcoholic fermentation may occur in a number of yeasts hitherto considered as non‐fermentative. Thus, shake‐flask cultures ofHansenula nonfermentansandCandida silvaefermented more than half of the available sugar to ethanol. It is concluded that the taxonomic test for fermentation capacity, which relies on detection of gas formation in Durham tubes, is not reliable for a physiological classification of yeasts as fermentative and non‐ferment

ISSN:0749-503X    

DOI:10.1002/yea.320020208

出版商:John Wiley&Sons, Ltd.    

年代:1986

数据来源: WILEY

摘要:

AbstractThePHO80gene, which is one of the regulatory genes exerting negative control in thephosystem ofSaccharomyces cerevisiae, was cloned. The 1·8 kb DNA fragment carrying thePHO80gene was sequenced and one open reading frame large enough to encode 293 amino acids was found in the sequence. Northern blot analysis of poly(A)+‐RNA isolated from cells grown under repressed and derepressed conditions revealed that (i) the size of thePHO80message was around 1·4 kb, (ii) the expression of thePHO80gene was not affected by the presence or absence or absence of inorganic phosphate in the medium, and (iii) the expression of thePHO80gene was not affected bypho2, pho4, pho81, or bypho80itself. a centromere sequence was found downstream of thePHO80coding reg

ISSN:0749-503X    

DOI:10.1002/yea.320020209

出版商:John Wiley&Sons, Ltd.    

年代:1986

数据来源: WILEY

ISSN:0749-503X    

DOI:10.1002/yea.320020210

出版商:John Wiley&Sons, Ltd.    

年代:1986

数据来源: WILEY

ISSN:0749-503X    

DOI:10.1002/yea.320020211

出版商:John Wiley&Sons, Ltd.    

年代:1986

数据来源: WILEY