Abstract

Production and partial purification of protease enzyme by Bacillus laterosporuswas the aim of this study. B. laterosporus was allowed to grow in shake flask broth culture for purpose of inducing protease enzyme. The protease enzyme was purified by ammonium sulfate precipitation followed by dialysis and further concentrated by Amicon tubes. After concentration, the protein was subjected to 12% Zymogram gel with gelatin and the molecular weight of the protease enzyme was 15 kDa. The protease activity increased as there was increase in enzyme concentration; optimum substrate concentration (starch) was 1.0% (w/v); an optimum incubation temperature was 40°C. Purified protease enzyme had a maximum activity at pH 7.0 of phosphate buffer and the optimum incubation time was 24 h. The protease isolated from B. latrosporus is a mesophilic protease. It is stable at pH 7, at 40°C temperature, and this enzyme can be exploited commercially.

Key words: Bacillus laterosporus, PMSF, β-mercaptoethanol, protease, fermentation