酵素工学
オープンアクセス

概要

Evaluation and Characterization of Protease Production by Bacillus Sp.Induced By UV-Mutagenesis

Neha Karn and Santosh Kumar Karn

 Phenotypic mutants of Bacillus sp. were developed by UV irradiation to test their ability to enhance protease activity. Among the five mutants, RS1 was found to be more efficient as compared to other mutants and wild-type strain. The maximum protease was obtained from the cell extract of Bacillus sp. RS1 strain, which was used for purification, and characterization. The culture filtrate from Bacillus sp. RS1 was purified with ammonium sulfate precipitation; the culture filtered supernatant had shown highest specific protease activity and contained 86% of the overall protease percentage of the culture. An ammonium sulfate precipitation between 40-70% was used for purifying the protease and resulted in a 20-fold increase in specific activity compared to the unconcentrated supernatant. The column purification resulted in a 44-fold increase in specific activity compared to the unconcentrated supernatant of Bacillus sp. RS1. On the basis of the results obtained, the mutant strain RS1 was found most suitable for the purification of the protease enzyme. Purified protease enzyme had a maximum activity at pH 7.0 with phosphate buffer and the optimum incubation time was 24 hr. The protease isolated from RS1 is stable at pH 8.5 and temperature 60°C, further this enzyme can be exploited commercially.