Biophysicochemical characterization of an alkaline protease from Beauveria sp. MTCC 5184 with multiple applications.

This study illustrates the biophysicochemical properties of an alkaline protease, BAP (Beauveria sp. alkaline protease) from Beauveria sp. MTCC 5184. This protease exhibited maximum activity at 50 °C, pH 9.0, and stability in a broad pH range, in the presence of organic solvents, denaturants, as well as detergents. Wash performance studies revealed that BAP was able to remove blood clots/stains from blood-soaked cloth. Peptide mass fingerprinting results demonstrated partial homology of BAP with subtilisin-like proteinase. BAP showed catalytic activity against natural as well as synthetic substrates. Active site characterization of BAP confirmed the involvement of serine, tryptophan, and aspartic acid in catalytic activity. Detailed kinetic and thermodynamic studies of BAP demonstrated that the activation energy (Ea) for casein hydrolysis was 82.55 kJ/M, the specificity constant (Kcat/K m), and the values of ∆G (change in Gibbs free energy) decreased with increase in temperature, whereas ∆H (change in enthalapy) and ∆S (change in entropy) were constant. The results of the present study indicate that BAP has potential for applications as detergent additive, in peptide synthesis, and in basic research.