Purification and characterization of a novel α-glucosidase from Malbranchea cinnamomea.

ABSTRACT

OBJECTIVES: To characterize a novel α-glucosidase from the thermophilic fungus Malbranchea cinnamomea. RESULTS: The enzyme was purified to homogeneity with purification fold of 40 and a recovery of 7.2 %. It was a monomer with molecular mass of 65.7 kDa on SDS-PAGE. It was optimally active at pH 6 and 50 °C (measured over 10 min) and exhibited a wide range of substrate specificity with the highest specific activity of 47.4 U mg(-1) for p-nitrophenyl α-D-glucopyranoside (pNPGlu) followed by isomaltose, panose and sucrose, suggesting that the enzyme belongs to the type I α-glucosidases. The K m values of the α-glucosidase for pNPGlu and isomaltose were 1.1 and 19.3 mM, respectively. CONCLUSION: Because of its unique properties, the α-glucosidase may have a potential in several industrial applications.