Partial purification and characterization of a thermostable alkaline protease from Lactobacillus brevis

• Published in: Malaysian Journal of Microbiology Vol. 8; no. 1; pp. 1 - 5
• Main Authors: Femi-Ola, T. O., Oladokun, D. O.
• Format: Journal Article
• Language: English
• Published: Malaysian Society for Microbiology 01.03.2012
• Subjects: Alkaline; Detergent; Inhibitors; Lactobacillus; Protease
• ISSN: 2231-7538; 1823-8262; 2231-7538
• DOI: 10.21161/mjm.28310

Aims: The research was done to study the partial purification and characterization of thermostable alkaline protease from Lactobacillus brevis.Methodology and Results: The enzyme was purified in a two-step procedure involving ammonium sulphate precipitation and Sephadex G-150 gel permeation chromatography. The protease was purified 8.04 fold with a yield of approximately 30% after purification with Sephadex G-150 column. It has a relative molecular weight of 33.2 kDa and optimally active at a temperature of 60 oC and pH 9.0. The maximum velocity Vmax and Michaelis constant Km of the protease produced during the hydrolysis of casein were 66.66 U/mg protein and 3.33 mg/ml. It was strongly activated by Ca2+ and ethylene diamine tetra acetic acid (EDTA), mildly inhibited by Na+, K+, Mg2+ and Fe2+ and strongly inhibited by Cu2+ and Hg2+. The ability of the enzyme to improve the cleansing power of various detergents was also studied. Conclusion, significance and impact of study: The findings in this study suggest that the protease is a suitable candidate for detergent formulation and biotechnological applications.