Galactose induces inSaccharomyces cerevisiaesensitivity of the utilization of hexoses to inhibition byD-glucosamine
作者:
Julián Nevado,
Claudio F. Heredia,
期刊:
Canadian Journal of Microbiology
(NRC Available online 1996)
卷期:
Volume 42,
issue 1
页码: 6-11
ISSN:0008-4166
年代: 1996
DOI:10.1139/m96-002
出版商: NRC Research Press
数据来源: NRC
摘要:
Inhibition by glucosamine of the utilization of hexoses bySaccharomyces cerevisiaeis induced by growing the cells in media with galactose as carbon source. The intensity of inhibition parallels the induction of the galactose pathway. These findings contrast with the fact that glucosamine is a substrate of the constitutive glucose but not of the inducible galactose transport and phosphorylation systems. The inhibition by glucosamine is pH dependent; the extent seems to be related with the phosphorylation of the hexosamine, as shown by its greater effect with substrates or with conditions that less interfere with the phosphorylation of the inhibitor. Inhibition is not a consequence of ATP depletion of the cell. Intracellular accumulated glucosamine derivatives impair the transport of glucose and mannose in yeast cells grown in galactose-supplemented media but not those grown with glucose or ethanol supplements (i.e., under conditions in which the utilization of these sugars is inhibited). However, impairment of the transport is not enough to explain the characteristics of the observed inhibition. The changes induced by growing the yeast in galactose that render the cells sensitive to glucosamine are under the control of thegal80andgal4genes.Key words: yeast, glycolysis inhibition, glucosamine,Saccharomyces cerevisiae.
点击下载:
PDF
(800KB)
返 回