title: Catabolite inactivation of the glucose transport system in Saccharomyces cerevisiae.
abstract: The sugar transport systems of Saccharomyces cerevisiae are irreversibly inactivated when protein synthesis is inhibited. This inactivation is responsible for the drastic decrease in fermentation observed in ammonium-starved yeast and is related to the occurrence of the Pasteur effect in these cells. Our study of the inactivation of the glucose transport system indicates that both the high-affinity and the low-affinity components of this system are inactivated. Inactivation of the high-affinity component evidently requires the utilization of a fermentable substrate by the cells, since inactivation did not occur during carbon starvation, when a fermentable sugar was added to starved cells, inactivation began, when the fermentation inhibitors iodoacetate or arsenate were added in addition to sugars, the inactivation was prevented, when a non-fermentable substrate was added instead of sugars, inactivation was also prevented. The inactivation of the low-affinity component appeared to show similar requirements. It is concluded that the glucose transport system in S. cerevisiae is regulated by a catabolite-inactivation process.
mesh_terms: D000255:Adenosine Triphosphate / Q000378:metabolism; D001692:Biological Transport; D002268:Carboxypeptidases / Q000378:metabolism; D043402:Cathepsin A; D003546:Cysteine Endopeptidases; D010450:Endopeptidases / Q000378:metabolism; D000431:Ethanol / Q000378:metabolism; D005947:Glucose / Q000378:metabolism*; D007700:Kinetics; D012441:Saccharomyces cerevisiae / Q000378:metabolism*; D029701:Saccharomyces cerevisiae Proteins; D014994:Xylose / Q000378:metabolism
chemical_list: D029701:Saccharomyces cerevisiae Proteins; D000431:Ethanol; D000255:Adenosine Triphosphate; D014994:Xylose; D002268:Carboxypeptidases; D010450:Endopeptidases; D043402:Cathepsin A; C499283:PRC1 protein, S cerevisiae; C022633:serine carboxypeptidase; C019836:CPS1 protein, S cerevisiae; D003546:Cysteine Endopeptidases; C028307:endopeptidase B; D005947:Glucose