Fibrinolytic enzyme production by newly isolated Bacillus cereus SRM-001 with enhanced in-vitro blood clot lysis potential.

Abstract

The discovery of plasmin-like microbial fibrinolytic enzymes having high specificity and negligible side effects is crucial for thrombolytic therapy. Herein, we report one such extra-cellular fibrinolytic enzyme producing Bacillus cereus SRM-001 isolated from the blood-laden soil of a chicken dump yard. The potency of the enzyme was established with fibrin plate assay and in-vitro blood clot lysis assay. The shake-flask operating parameters and media composition were optimized for maximizing the productivity of the enzyme. The operating parameters, pH 7, 37°C, 1% inoculum volume and 24 h inoculum age, were found to be the optimum. The levels of media components, corn flour (0.3% w/v), soyabean powder (1.9% w/v) and MnSO4 (11.5 mM) were optimized by statistical analysis using Box-Behnken design derived RSM. This resulted in an almost 1.8 fold increase in fibrinolytic enzyme productivity. The 3D response surface plots showed soyabean powder and MnSO4 to be the key ingredients for enhancing the enzyme productivity, whereas corn flour had a marginal effect. The in-vitro blood clot lysis assay conducted at near physiological pH 7 at 37°C showed the enzyme to be a potential therapeutic thrombolytic agent.