Occurrence of an endo-1,3-beta-glucanase in culture fluids of the yeast Candida utilis. Purification and characterization of the enzyme activity.
The endo-1,3-beta-glucanase (EC 3.2.1.6) secreted into the culture medium by cells of Candida utilis was isolated and purified to homogeneity on polyacrylamide-gel electrophoresis and in ultracentrifugation studies (s20,w = 1.97S). The purified enzyme represented only 0.001% of the total 1,3-beta-glucanase activity, the remainder being due to an exo-1,3-beta-glucanase enzyme, and behaved as an acidic glycoprotein (pI 3.3) in isoelectric-focusing experiments. The mol.wt. was estimated to be 21 000 by gel filtration and polyacrylamide-gel electrophoresis. Studies on the hydrolysis of different substrates showed that the enzyme was only able to break down (1 leads to 3)-beta-linkages, by an endo-splitting mechanism. Glucono-delta-lactone, D-glucoronolactone and heavy metal ions such as Hg2+ were inhibitors of the enzyme activity. The function of this endo-beta-glucanase in C. utilis is discussed.
D002175:Candida / Q000201:enzymology*; D004693:Glucan Endo-1,3-beta-D-Glucosidase / Q000037:antagonists & inhibitors / Q000302:isolation & purification / Q000378:metabolism; D006026:Glycoside Hydrolases / Q000378:metabolism; D006868:Hydrolysis; D007700:Kinetics; D013379:Substrate Specificity
D006026:Glycoside Hydrolases; D004693:Glucan Endo-1,3-beta-D-Glucosidase