Production and characterization of protease from Bacillus subtilis A8 isolated from soil

In this study, bacteria were isolated from soil sample taken from Mount Ergani Authority. Bacteria which isolated with the help of biochemical tests and 16S rRNA analysis defined as Bacillus subtilis A8. Optimal conditions of bacterial growth were determined at 24th hour, 37°C and pH 7.0, respectively. Optimum production time was 24 hours, optimum temperature was 37°C and optimum pH was 9.0. Carbon and nitrogen sources were added to the production medium of the bacteria to investigate their effect on the production of protease. In carbon resources; starch, glucose, maltose, lactose protease production of approximately three-fold increase, galactose addition of enzyme production was observed to decrease. Among the nitrogen sources, the highest protease activity was reached with urea, while the addition of ammonium sulfate decreased the enzyme production significantly. After optimum conditions was determined, the enzyme partial was purified. To determine the effect of some detergents on the partially purified enzyme 0.5% SDS, Tween-40, Tween-80 and TritonX-100, BRIJ was used. While it was seen that SDS inhibited protease activity by 80%, it was found that other detergents had no significant effect on enzyme activity. When the effect of inhibitors such as EDTA (Ethylenediamintetra acetic acide), PMSF (Phenylmethylsulfonyl flüoride), DTT (Dithiothreitol) and β-mercaptoethanol on the partially purified protease was examined, the highest inhibition effect was obtained with 10 mM PMSF (92%).