Villa T G, Notario V, Villanueva J R
Biochem J. 1979 Jan 1;177(1):107-14. doi: 10.1042/bj1770107.
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.
对产朊假丝酵母细胞分泌到培养基中的内切-1,3-β-葡聚糖酶（EC 3.2.1.6）进行了分离纯化，经聚丙烯酰胺凝胶电泳和超速离心研究（沉降系数s20,w = 1.97S）后达到了均一性。纯化后的酶仅占总1,3-β-葡聚糖酶活性的0.001%，其余活性归因于一种外切-1,3-β-葡聚糖酶，并且在等电聚焦实验中表现为酸性糖蛋白（pI 3.3）。通过凝胶过滤和聚丙烯酰胺凝胶电泳估计其分子量为21000。对不同底物水解的研究表明，该酶只能通过内切断裂机制分解（1→3）-β-键。葡萄糖酸-δ-内酯、D-葡糖醛酸内酯和Hg2+等重金属离子是该酶活性的抑制剂。本文讨论了这种内切β-葡聚糖酶在产朊假丝酵母中的功能。
