Isolation and Identification of Alkaline Protease Producer from Selected Alkaline Habitat

Abstract

Efficient alkaline protease producing fungus was isolated from composite soil sample collected from the vicinity of Lonar Soda Lake ( Latitude 19° 58', Longitude 76° 36'). It was designated as LAF1 and identified as Rhizopus sp. on the basis of macro- and micromorphological features. Alkaline protease production was carried out in solid state fermentation system using whey and defatted seed meal of soybean and sunflower. Further extraction, partial purification and characterization of alkaline protease were carried out. After dialysis, the enzyme resulted in 1.10-fold increase which exhibited 14.41 U specific activity/mg of protein with 71.81 % yield. Molecular weight of the dialyzed alkaline protease was determined 40 kd. Catalytic activity of partially purified LAF1 alkaline protease was recorded at pH 10.0, temperature 55 o C and 14 mg/mL casein concentration. Lineweaver-Burk double reciprocal plot was constructed and Km and Vmax values were determined 2525.30 mg/mL and 166.67 U/mL/min respectively. Catalytic activity of LAF1 partially purified alkaline protease was completely inhibited in presence of 5 mM EDTA, therefore the enzyme belongs to class metalloprotease. Partially purified alkaline protease from LAF1 showed excellent stability and activity in presence of various solvents, surfactants, Oxidizing agent and detergents.