Purification and characterization of keratinase from native feather-degrading streptomyces albus

The keratin occurs naturally in the form of feathers, hair, nails and wool all over the world. As the physiological and chemical methods of keratin degradation are not easy possible, the biological method has gained importance. It can be biodegraded by some Keratinolytic Streptomyces sp. The present study investigated purified keratinase from Keratinolytic Streptomyces albus. The cell-bound keratinolytic enzyme was purified 28.91 fold by gel filtration chromatography. The enzyme was characterized as a serine protease with a molecular mass of 40-45kD. Optimal activity pH and Temperature were measured at 7.0 and 400C, furthermore the various inhibitors had different effect on enzyme activity. PMSF and heavy metal ion Hg+2 were the most potent inhibitors and EDTA induced the activity by more than 142%, 2-mercaptoethanol did not show any impact on the enzyme, where pCMB, KCN, 8-hydroxyquinoline and cystine inhibited activity moderately.