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从拟康氏木老霉TrichodermapseudokoninguS－38菌株发酵液中分离纯化了一个外切葡聚糖纤维二糖水解酶（CBHI，EC3．2．1．91）和一个内切葡聚糖酸（ECI，EC3．2．1.4)。经木瓜蛋白酶有限酶切，分别都得到了一个对可溶性废物具有与天然酶相近活力的催化结构域和合两个短肽的能吸附纤维素的吸附结构域。C末端测定结果表明：内切酶的催化结构城位于天然萌分子的C端，圆二色谱测定表明其催化域具有与天然酶相似的结构特征。由有限醇切内、外切葡聚糖酶得到两个短肽的混合物还都表现了具有破坏纤维素聚合物结构，形成短纤维的能力。外切纤维素酶的N端是封闭的，全酶分子的含糖量为12％，而催化域仅为1．5％；远紫外CD测定表明：CBHI分子缺乏220um的“trough”．a-螺旋含量也很少;具195nm的正峰和205－215m的负峰，表明了它是一个窗含β-结构的蛋白。当降低pH值(6~3．2），CBHI和其催化结构域（CBHI－core）的构象只发生了微小的改变；而当纤维二糖加入后，CBHI和CBHI－core的构象不再随pH位变化而变化，两者的光谱性质也非常相似，这表明CBHI的光谱性质主要由其催化域决定。对外切葡聚塘纤维二糖水解酶和内切葡聚糖酶发生N-糖基化时的序列模式，及其与酶蛋白结构和功能的关系也进行了讨论。
An exo-dextran cellobiohydrolase (CBHI, EC3.2.1.91) and an endoglucan (ECI, pH 7.4) were isolated and purified from the fermentation broth of Trichoderma pseudokoningu S-38 strain. EC 3.2.1.4). Restriction enzyme digestion with papain each resulted in an adsorptive cellulose-adsorbing domain with a catalytic domain that is nearly as active as the native enzyme for soluble wastes, and two short peptides, respectively. The results of C-terminal assay showed that the catalytic structure of the endonuclease was located at the C-terminal of the natural Meng molecule, and circular dichroism spectroscopy showed that the catalytic domain of the enzyme had similar structural characteristics as the native enzyme. The mixture of two short peptides obtained by cutting endo-exo-exo-glucanase with a limited amount of alcohol also shows the ability to disrupt cellulose polymer structure and form short fibers. Exocellulase N-terminal is closed, the holoenzyme molecular sugar content of 12%, while the catalytic domain was only 1.5%; far UV CD measurement showed that: CBHI molecules lack of 220um “trough.” The a-helix content is also small; a positive peak of 195 nm and a negative peak of 205-215 m indicate that it is a β-structure-containing protein. The conformation of CBHI and its catalytic domain (CBHI-core) changed only slightly when the pH was lowered (6 to 3.2); conformation of CBHI and CBHI-core no longer changed with the addition of cellobiose pH changes, the spectral properties of the two are very similar, indicating that the spectral properties of CBHI mainly determined by its catalytic domain. The sequence patterns of N-glycosylation of exo-cut polyangular cellobiohydrolases and endoglucanases and their relationship to the structure and function of the enzyme proteins are also discussed.