Purification and characterization of beta-1,4-glucosidase from Clostridium papyrosolvens

Clostridium papyrosolvens CFR-1010 was selected for the anaerobic extracellular production of beta-1,4-glucosidase. The enzyme was purified by alcohol precipitation and DEAE ion-exchange chromatography. Its homogeneity was confirmed by SDS/PAGE. The enzyme had a molecular mass of 85 kDa. The maximum enzyme activity was observed at pH 5.0 and 50 degrees C. The enzyme activity was inhibited by Ca2+, Co2+, Cu2+, Zn2+, Fe2+, Mg2+ and Na+ ions. However, the activity increased (158%) in the presence of MnCl2, whereas it decreased by 80% in the presence of N-bromosuccinimide, suggesting the presence of tryptophan residues at the active site of enzyme. The enzyme had a K(m) of 15 mg/ml and Vmax of 125 units/min per mg of protein.