PURIFICATION AND PARTIAL CHARACTERIZATION OF 2 EXTRACELLULAR KERATINASES OF SCOPULARIOPSIS-BREVICAULIS

Two extracellular keratinases of Scopulariopsis brevicaulis were purified and partially characterized. The enzymes were isolated by the techniques of gel filtration chromatography and sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE). These keratinases (K I & K II) were purified approximately 33 and 29 fold, respectively. SDS-PAGE of the products of gel filtration chromatography (K I & II) produced only one band each, suggesting homogeneity. The optimum pH for both keratinases was 7.8, while the optimum temperatures were 40-degrees-C (K I) and 35-degrees-C (K II). Estimated molecular weights were 40-45 KDa and 24-29 KDa for K I & K II respectively. Both keratinases were inhibited by phenylmethylsulfonyl fluoride which suggests a serine residue at or near an active site.