title: Yeast protease B-digested skimmed milk inhibits angiotensin-I-converting-enzyme activity.
abstract: Angiotensin-1-converting-enzyme (ACE) inhibitory activity was identified in skimmed milk digested with cell-free extract of yeast Saccharomyces cerevisiae. Simultaneously, a protease enzyme involved in the production of ACE-inhibition materials in digested skimmed milk was purified to homogeneity from the cell-free extracts of S. cerevisiae by ammonium sulphate fractionation and chromatography in DEAE-Sephacel, D-tryptophan methyl ester-Sepharose 4B, Hiload Superdex G-200 and HPLC Mono-Q chromatography. The purified enzyme was identified as protease B, based on the molecular mass on SDS/PAGE and the N-terminal amino acid sequence of the enzyme. The optimum pH for digestion of skimmed milk and production of ACE-inhibition materials was pH 4.8. The IC(50) of the hydrolysate was 0.42 mg of protein/ml when skimmed milk was digested with yeast protease B.
authors.affiliation: Department of Bioresources, Faculty of Agriculture, Ehime University, Matsuyama, Ehime 790, Japan.
authors.forename: M K
authors.initials: MK
authors.lastname: Roy
authors.forename: Y
authors.initials: Y
authors.lastname: Watanabe
authors.forename: Y
authors.initials: Y
authors.lastname: Tamai
mesh_terms: D000595:Amino Acid Sequence; D000806:Angiotensin-Converting Enzyme Inhibitors / Q000302:isolation & purification / Q000378:metabolism*; D000818:Animals; D001709:Biotechnology; D006863:Hydrogen-Ion Concentration; D066298:In Vitro Techniques; D008892:Milk / Q000737:chemistry / Q000378:metabolism*; D008969:Molecular Sequence Data; D008970:Molecular Weight; D012441:Saccharomyces cerevisiae / Q000201:enzymology / Q000235:genetics; D012697:Serine Endopeptidases / Q000235:genetics / Q000302:isolation & purification / Q000378:metabolism*; D029701:Saccharomyces cerevisiae Proteins
chemical_list: D000806:Angiotensin-Converting Enzyme Inhibitors; D012697:Serine Endopeptidases; C023302:yeast proteinase B; D029701:Saccharomyces cerevisiae Proteins