Purification and characterization of alkaline protease produced by Streptomyces flavogriseus and its application as a biocontrol agent for plant pathogens

Background A protease is an enzyme that helps proteolysis: protein catabolism by hydrolysis of peptide bonds. Proteases were the first enzymes to be commercialized, partly on the account of the history of availability and on account of need. Aim The aim of the present work is studying the properties of the partially purified enzyme and some application of the enzyme. Materials and methods In this study, alkaline protease was produced by Streptomyces flavogriseus using the shaking method. The enzyme was partially purified by ammonium sulfate precipitation. The most active fraction was evaluated on Sephadex G-100 column chromatography. The activity of the enzyme was determined at different temperatures and different pH values using various buffers. Results and conclusion In this study, alkaline protease produced by S. flavogriseus was partially purified by ammonium sulfate precipitation at 75% w/v saturation and pooled on Sephadex G-100 with a yield of 60.85% and specific activity of 85.14 U/mg protein. The enzyme was optimally active at 45°C in 0.5 mol/l potassium phosphate buffer (pH 8.0) after 30 min of incubation and was broadly stable at 45°C for 60 min and pH 6-8. The alkaline protease relative activity was increased in the presence Mn2+, Co2+, K+, Na+, Fe2+, and Mg2+ at concentration 1 mmol/l, respectively.