Keratinase of Bacillus cereus Lr3/2 KP015746 from deteriorated leather samples

Abstract

Keratin is an insoluble fibrous protein found in hair, wool, feather, nail, horns and other epithelial covering. The high resistance of keratin to proteases is due to its densely packed and strongly stabilized by several hydrogen bonds and hydrophobic interactions, in addition to several disulfide bonds. A keratinase enzyme is useful for biotechnological purposes, and also for hydrolysis of de-hairing of bovine hides, poultry feathers, and leather surplus. In the present study, B. cereus KJ72442 was isolated from deteriorated leather samples using feather meal as a substrate and identified by 16SrDNA sequencing and with accession number B. cereus Lr3/2 KP015746). The colony showing the highest zone of keratin hydrolysis on feather meal agar was selected for keratinase production. B. cereus showed efficient keratinase production 41.06±2U/ml at optimum temperature of 37°C and pH 7 after 72h using 1% feather meal as a substrate. B. cereus keratinolytic activity was found to be metalloprotease, as inhibited by 1mM EDTA but not by PMSF.In addition to keratinase, B. cereus KP015746 (Lr3/2) was also proficiently found to produce collagenase, caseinase and gelatinase. On the lab scale, the efficiency of B. cereus Lr3/2 KP015746 keratinase to degrade leather was analyzed and observed excellent results. Hence, the experimental outcome revealed that B.cereus KP015746 (Lr3/2) can be effectively used to treat keratin, collagen rich agro industrial waste ecofriendly.