title: Proteinase yscD. Purification and characterization of a new yeast peptidase.
abstract: A newly recognized peptidase, designated proteinase yscD, was purified from the yeast Saccharomyces cerevisiae. The enzyme cleaves the Pro-Phe bond of the synthetic peptide substrate Bz-Pro-Phe-Arg-4-nitroanilide and the Ala-Ala bond of Ac-Ala-Ala-Pro-Ala-4-nitroanilide, Ac-Ala-Ala-Pro-Phe-4-nitroanilide, and MeO-Suc-Ala-Ala-Pro-Met-4-nitroanilide with high efficiency (Bz-, Ac-, and MeO-Suc are defined as benzoyl, acetyl, and methoxy-succinyl, respectively). [3H]Methylcasein does not serve as a substrate. Optimum pH for cleavage of Bz-Pro-Phe-Arg-4-nitroanilide is in the range of 6.5 to 7; for Ac-Ala-Ala-Pro-Ala-4-nitroanilide the range is between 5.75 and 6. For MeO-Suc-Ala-Ala-Pro-Met-4-nitroanilide the pH optimum was found to be 5.5. The purified enzyme has an apparent Stokes radius of Rs = 37.9 A as judged by gel chromatography. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis indicates a molecular weight of approximately 83,000 for the enzyme. Mercurials and EDTA were found to be potent inhibitors of proteinase yscD activity.
mesh_terms: D000595:Amino Acid Sequence; D002863:Chromogenic Compounds / Q000378:metabolism; D003546:Cysteine Endopeptidases; D010450:Endopeptidases / Q000302:isolation & purification*; D007526:Isoelectric Point; D007700:Kinetics; D008970:Molecular Weight; D012441:Saccharomyces cerevisiae / Q000201:enzymology*; D013379:Substrate Specificity
chemical_list: D002863:Chromogenic Compounds; D010450:Endopeptidases; D003546:Cysteine Endopeptidases; C045096:proteinase yscD