STUDIES ON THE GENUS MONASCUS

I. PURIFICATION AND PROPERTIES OF TWO FORMS OF GLUCOAMYLASE FROM MONASCUS KAOLIANG NOV. SP. F-1

Abstract

Two forms of glucoamylase [α-D-(1→4)-glucan glucohydrolase, EC 3.2.1.3] were isolated and purified from the culture of Monascus kaoliang nov. sp. F-1 on wheat bran. These glucoamylases were separated from each other by polyacrylamide gel electrophoresis or by gel filtration on Sephadex G-150 column. They were designated as GA-I and GA-II in the order of elution from the column. The purified enzymes were homogeneous in polyacrylamide gel electrophoresis. The pH optima of GA-I and -II were found to be 4.5 and 4.7, respectively. GA-I was more resistant than GA-II against treatment with urea or guanidine. The approximate molecular weights by sodium dodecyl sulfate-polyacrylamide gel electrophoresis of GA-I and -II were estimated to be 4.8×10⁴ and 6.8×10⁴, respectively.