Production and purification of alkaline protease from Exiguobacterium indicum TBG-PICH-001 isolated from soil samples of Pichavaram Estuary (Tamil Nadu)

摘要

A proteolytic bacterial strain, TBG-PICH-001, was isolated from soil of Pichavaram estuary, Tamil Nadu, and was identified as Exiguobacterium indicum based on 16S rDNA sequence similarity. Parameters such as incubation time, temperature, initial pH, rate of agitation and inoculum required for peak production of the protease by the newly isolated bacterium under submerged fermentation were optimized using one factor at a time method. Maximum protease production was observed after 48 hrs of incubation at 35 degrees C with constant stirring at 100 rpm, at an initial pH of 10. Reduced incubation time for enzyme production shows the industrial viability of the strain. Purification of enzyme was achieved by ammonium sulphate fractionation followed by ion-exchange chromatography with DEAE-Cellulose, to give total yield of 27%. The molecular weight determined by SDS-PAGE was approximately 60 kDa.