title: Purification and characterization of a keratinolytic serine proteinase from Streptomyces albidoflavus.
abstract: Streptomyces strain K1-02, which was identified as a strain of Streptomyces albidoflavus, secreted at least six extracellular proteases when it was cultured on feather meal-based medium. The major keratinolytic serine proteinase was purified to homogeneity by a two-step procedure. This enzyme had a molecular weight of 18,000 and was optimally active at pH values ranging from 6 to 9.5 and at temperatures ranging from 40 to 70 degrees C. Its sensitivity to protease inhibitors, its specificity on synthetic substrates, and its remarkably high level of NH2-terminal sequence homology with Streptomyces griseus protease B (SGPB) showed that the new enzyme, designated SAKase, was homologous to SGPB. We tested the activity of SAKase with soluble and fibrous substrates (elastin, keratin, and type I collagen) and found that it was very specific for keratinous substrates compared to SGPB and proteinase K.
authors.affiliation: Laboratoire de Génie Enzymatique et Biovalorisation (Unité du Laboratoire de Chimie des Substances Naturelles), I.U.T., Département de Génie Biologique, Limoges, France.
authors.forename: P
authors.initials: P
authors.lastname: Bressollier
authors.forename: F
authors.initials: F
authors.lastname: Letourneau
authors.forename: M
authors.initials: M
authors.lastname: Urdaci
authors.forename: B
authors.initials: B
authors.lastname: Verneuil
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D003470:Culture Media; D005241:Feathers / Q000737:chemistry / Q000378:metabolism; D006863:Hydrogen-Ion Concentration; D007220:Industrial Waste; D007633:Keratins / Q000378:metabolism; D008969:Molecular Sequence Data; D010447:Peptide Hydrolases / Q000737:chemistry / Q000302:isolation & purification* / Q000378:metabolism*; D011480:Protease Inhibitors / Q000494:pharmacology; D016415:Sequence Alignment; D013302:Streptomyces / Q000201:enzymology* / Q000254:growth & development; D013379:Substrate Specificity; D013696:Temperature
chemical_list: D003470:Culture Media; D007220:Industrial Waste; D011480:Protease Inhibitors; D007633:Keratins; D010447:Peptide Hydrolases; C035855:keratinase