title: Properties of a non collagen-degrading Bacillus subtilis keratinase.
abstract: Bacillus subtilis S14 produces a keratinase (KerS14) with non collagen-degrading activity. Indeed, this is the first keratinase described so far that does not have any detectable effect on collagen, which is a crucial property for an enzyme intended to be used in skin dehairing. Because of its importance as an industrial tanning enzyme, we report the biochemical characterization of KerS14. This protein exhibited an apparent molecular mass of 27 kDa, a pI of 6.5, and an optimum pH in the range of 8.0-9.0. The enzyme's activity was stimulated by Mn2+ (7.7-fold), Ca2+ (6.1-fold), Mg2+ (4.9-fold), and Co2+ (4.0-fold) but was inhibited by Cu2+ and Zn2+. Using p-nitroanilide and methylcoumarine derivatized peptides, we observed that KerS14 prefered Arg at subsite P1, small amino acid residues at subsite P2, and Gln or Glu at subsite P3. KerS14 presented higher keratin degradation specificity than other commercial proteases. Its high keratinolytic activity and the absence of virtually any activity against collagen remark the biotechnological potential of this enzyme to be used at larger scales in tannery dehairing processes.
authors.affiliation: Centro de Biotecnologia do Estado do Rio Grande do Sul, and Faculdade de Farmacia, Universidade Federal do Rio Grande do Sul, Rio Grande do Sul, Brazil.
authors.forename: Alexandre José
authors.initials: AJ
authors.lastname: Macedo
authors.forename: Walter Orlando
authors.initials: WO
authors.lastname: Beys da Silva
authors.forename: Carlos
authors.initials: C
authors.lastname: Termignoni
mesh_terms: D001412:Bacillus subtilis / Q000201:enzymology*; D002412:Cations / Q000494:pharmacology; D003094:Collagen / Q000378:metabolism*; D020536:Enzyme Activators / Q000494:pharmacology; D004791:Enzyme Inhibitors; D004795:Enzyme Stability; D006863:Hydrogen-Ion Concentration; D007526:Isoelectric Point; D008670:Metals / Q000494:pharmacology; D008970:Molecular Weight; D010447:Peptide Hydrolases / Q000737:chemistry / Q000302:isolation & purification / Q000378:metabolism*; D010455:Peptides / Q000378:metabolism; D013379:Substrate Specificity
chemical_list: D002412:Cations; D020536:Enzyme Activators; D004791:Enzyme Inhibitors; D008670:Metals; D010455:Peptides; D003094:Collagen; D010447:Peptide Hydrolases; C035855:keratinase