Two-Step Purification and Partial Characterization of Keratinolytic Proteases from Feather Meal Bioconversion by Bacillus sp. P45

This study aimed to purify and partially characterize a keratinolytic protease produced by Bacillus sp. P45 through bioconversion of feather meal. Crude extract was purified using sequence an aqueous two-phase system (ATPS) in large volume systems (10, 50, 500 g) increase obtaining enzyme, followed diafiltration (DF) step. Purified characterized terms protein profile analysis SDS-PAGE, optimum temperature pH, thermal deactivation kinetics at different temperatures performance the presence several salts (NaCl, CaCl2, MnCl2, CaO, C8H5KO4, MgSO4, CuSO4, ZnSO4, FeCl3) organic solvents (acetone, ethanol, methanol, acetic acid, diethyl ether, formaldehyde). ATPS with high capacities resulted purer without compromising purity yields, reaching purification factor up 2.6-fold 6.7-fold first second ATPS, respectively, 4.0-fold DF process. Recoveries were 79% both reached 84.3% after The electrophoretic demonstrated 25–28 kDa band related protease. protease’s pH 55 °C 7.5, respectively. energy (Ed) value 118.0 kJ/mol, while D (decimal reduction time) z (temperature interval required reduce one log cycle) values ranged from 6.7 237.3 min 13.6 18.8 °C, Salts such as MgSO4 increased activity, all caused its decrease. results are useful for future studies about scale-up enzyme application industrial processes.