ISOLATION AND CHARACTERIZATION OF A UNIQUE ENDO-BETA-1,6-GLUCANASE FROM THE YEAST SACCHAROMYCOPSIS-FIBULIGERA NCYC-451

A beta-glucanase enzyme has been described which has beta-1,6 activity but no beta-1,3 activity. It was isolated and purified from cell free extract and culture free medium of Saccharomycopsis fibuligera by a combination of techniques that included adsorption on DEAE-Sepharose and gel filtration through a Sephacryl S-300 column. The extracellular endo-beta-1,6-glucanase had similar physicochemical properties to those of the intracellular one. The intracellular enzyme behaved as an acidic protein with pl 3.95. It had an optimum pH of 5.5 and optimum temperature of 50 degrees C. The enzyme was specific for beta-1,6-glucosidic linkages by an endo-acting mechanism. The molecular weight of the intracellular enzyme was estimated at 51 kD from gel filtration compared with 43 kD for the extracellular enzyme.