A fibrinolytic, alkaline and thermostable metalloprotease from the newly isolated Serratia sp RSPB11

This study shows the purification and characterization of metalloprotease (serralysin) with fibrin and fibrinogenolytic property, from the newly isolated Serratia marcescens RSPB11. This protein macro molecule was more stable over a wide range of pH (6–10) and the temperatures up to 60 °C. It showed optimum enzyme activity at pH 9.0 and at a temperature of 37 °C. Inhibitory analysis revealed that this enzyme is metalloprotease and its enzyme activity could be regained by the addition of Co2+, Cu2+, Fe2+, Mg2+and Zn2+ ions after chelation of ions with EDTA. This enzyme showed the Michaelis–Menten's constant Km (1.261 mg/ml) for its substrate, casein and the observed maximum attainable velocity was Vmax (24,842 U/min). The purified enzyme showed an apparent molecular mass of approximately 50 kDa in SDS-PAGE. The results also suggested that this serralysin is having potential application thrombolytic therapy.