title: Stimulation of amino acid transport in Saccharomyces cerevisiae by metabolic inhibitors.
abstract: Inhibitors of energy metabolism (3-chlorophenylhydrazonomalononitrile, antimycin A, iodoacetamide, dicyclohexylcarbodiimide) but not of transport (uranyl ions) stimulate at low concentrations the uptake of L-leucine, L-glutamic acid, L-arginine and, to a lesser degree, of 2-aminoisobutyric acid in Saccharomyces cerevisiae. The effect is apparent only after augmenting the energy reserves of cells by preincubation with D-glucose or, more strikingly, with ethanol. It is absent in a mutant (op1) lacking the translocation system for ADP--ATP in mitochondria. The presence of two different energy reserves for amino acid transport is indicated (one in energy-poor, the other in energy-rich cells). The stimulating effect appears to be caused by a retarded degradation of the transport proteins as occurs at a lowered level of mitochondria-produced ATP.
mesh_terms: D000255:Adenosine Triphosphate / Q000378:metabolism*; D000596:Amino Acids / Q000378:metabolism*; D000968:Antimycin A / Q000494:pharmacology; D001693:Biological Transport, Active / Q000187:drug effects; D002258:Carbonyl Cyanide m-Chlorophenyl Hydrazone / Q000494:pharmacology; D004024:Dicyclohexylcarbodiimide / Q000494:pharmacology; D007460:Iodoacetamide / Q000494:pharmacology; D007700:Kinetics; D007930:Leucine / Q000378:metabolism; D012441:Saccharomyces cerevisiae / Q000378:metabolism*; D014501:Uranium / Q000494:pharmacology
chemical_list: D000596:Amino Acids; D014501:Uranium; D004024:Dicyclohexylcarbodiimide; D002258:Carbonyl Cyanide m-Chlorophenyl Hydrazone; D000968:Antimycin A; D000255:Adenosine Triphosphate; D007930:Leucine; D007460:Iodoacetamide