title: Inactivation of the galactose transport system in Saccharomyces cerevisiae.
abstract: The galactose transport system of Saccharomyces cerevisiae consists of one component which shows a Km value of approx. 4mM in growing cells. A rapid and irreversible inactivation of this transport is detected on impairment of protein synthesis. This inactivation shows the following characteristics: (i) it is due to changes in the Km and Vmax of the transport system; (ii) it follows first-order kinetics; (iii) it is an energy-dependent process and is stimulated by the presence of an exogenous carbon source; (iv) fermentable sub-dependent process and is stimulated by the presence of an exogenous carbon source; (iv) fermentable substrates stimulate inactivation more efficiently than non-fermentable substrates.
mesh_terms: D000255:Adenosine Triphosphate / Q000096:biosynthesis; D001693:Biological Transport, Active / Q000187:drug effects; D003513:Cycloheximide / Q000494:pharmacology; D000431:Ethanol / Q000494:pharmacology; D005690:Galactose / Q000378:metabolism*; D007700:Kinetics; D009584:Nitrogen / Q000502:physiology; D014176:Protein Biosynthesis; D012441:Saccharomyces cerevisiae / Q000378:metabolism*
chemical_list: D000431:Ethanol; D000255:Adenosine Triphosphate; D003513:Cycloheximide; D009584:Nitrogen; D005690:Galactose