Characteristics and functions of proteinase A and its inhibitors in yeast.
A purification and some properties of proteinase A from yeast are described. A specific macromolecular inhibitor of proteinase A from yeast cytosol has been isolated and shown to be a protein (molecular weight 7,700) consisting of a majority of polar amino acids. Proline, arginine, cysteine and tryptophan were not detected in the inhibitor. Possible biological functions of proteinase A and the proteinase A-inhibitor (and of other yeast proteinases and their inhibitors) in the following processes are discussed: general protein turnover, catabolite inactivation of enzymes, enzyme degradation at starvation and at transition to spore formation, and activation of pre-enzymes and precursor proteins by limited proteolysis.
D000596:Amino Acids / Q000032:analysis; D004791:Enzyme Inhibitors; D005656:Fungal Proteins / Q000502:physiology*; D006863:Hydrogen-Ion Concentration; D007700:Kinetics; D010447:Peptide Hydrolases / Q000302:isolation & purification; D011480:Protease Inhibitors; D012441:Saccharomyces cerevisiae / Q000201:enzymology*
D000596:Amino Acids; D004791:Enzyme Inhibitors; D005656:Fungal Proteins; D011480:Protease Inhibitors; D010447:Peptide Hydrolases