SCREENING AND CHARACTERIZATION OF KERATINASE FROM Bacillus licheniformis ISOLATED FROM NAMAKKAL POULTRY FARM

Keratin are insoluble fibrous proteins found in hair, wool, feather, nail, horns and other epithelial covering which is rich in beta helical coil linked through cysteine bridges. Keratinase (EC 3.4.4.25) belongs to the class hydrolase which are able to hydrolyse insoluble keratins more efficient than other proteases. The bacteria Bacillus licheniformis showing higher keratinase activity was screened out of the ten different bacterial strains isolated. The ability of Bacillus licheniformis to utilize chicken feather powder as a substrate was tested. It was found that maximum enzyme activity was 10.76U/ml. Similarly optimum temperature and pH for the enzyme activity was found to be 60C and 7.0 respectively. The km and Vmax values were 0.22 mg/ml and 0.01 U/ml respectively. The enzyme is stable (30-40C) and active around wide pH range (6-8). Among the various metal ions tested zinc, magnesium were found to enhance the enzyme activity where as mercury, copper, cadmium, 1, 10 phenanthroline and EDTA completely inhibit the enzyme activity. It was found from this study, organism such as Bacillus licheniformis isolated from poultry soil can be used as a potential candidate for degradation of feather and for dehairing process in leather industry. [Researcher 2010;2(4):89-96]. (ISSN: 1553-9865).