Purification and Biochemical Characterization of Fibrinolytic Enzyme Produced by Thermophilic Fungus Oidiodendron flavum

Fibrinolytic enzyme isolated from thermophilic fungus Oidiodendron flavum, precipitated by ammonium sulfate (70% saturation) and subsequent purification using DEAE-Cellulose and Sephadex G-25 columns, then produce one clear band on SDS-PAGE at molecular weight 22,000 Da. The purified fibrinolytic enzyme was active over a wide range of pH (6.0-11.0) with optimum point at pH 8.0. The enzyme was most active at 45 and 55°C all over the incubation time, but lost substantial activity upon incubation at more than 65°C. Upon heating to 70°C for 30 min, the activity completely disappeared. The enzyme activities were found to be enhanced by Mg2+ and Ca2+, but were inhibited by the Co2+, Cu2+, Zn2+ and Fe2+ ions, while Hg2+ at low concentrations strongly inhibited the enzyme activity.