Tiunova N A, Kobzeva N Ia
Biokhimiia. 1981 Jul;46(7):1175-82.
Endo-1.3-beta-glucanase (EC 3.2.1.39) from Actinomyces cellulosae was purified 960-fold by ion-exchange chromatography on DEAE-cellulose and DEAE-Sephadex A-50 and by gel-filtration through Acrylex P-60. The enzyme was electrophoretically homogeneous and had molecular weight of about 30 000 as determined by polyacrylamide gel disc-electrophoresis in the presence of SDS and gel-filtration through Sephadex G-200. The isoelectric point lies at 4.0; the pH optimum for the non-purified enzyme preparation is 5.5, that for the purified one is 6.0. The enzyme is stable within the pH range of 7.0-8.0 and is rapidly inactivated in acid media. The enzyme does not hydrolyze laminaribiose, lichenane, barley glucan, pustulane, KM-cellulose, but splits laminarane to form high molecular weight oligosaccharides, a small number of low molecular weight oligosaccharides and a negligible amount of glucose. Studies with glucose oxidase showed that splitting of 1.3-beta-glucan results in a beta-form of glucose.
纤维素放线菌的内切-1,3-β-葡聚糖酶（EC 3.2.1.39）通过在DEAE-纤维素和DEAE-葡聚糖A-50上进行离子交换色谱以及通过Acrylex P-60进行凝胶过滤，纯化了960倍。该酶在电泳上是均一的，在SDS存在下通过聚丙烯酰胺凝胶圆盘电泳和通过葡聚糖G-200进行凝胶过滤测定，其分子量约为30000。其等电点为4.0；未纯化的酶制剂的最适pH为5.5，纯化后的酶制剂的最适pH为6.0。该酶在pH 7.0 - 8.0范围内稳定，在酸性介质中迅速失活。该酶不水解层二糖、地衣多糖、大麦葡聚糖、脓杆菌聚糖、KM-纤维素，但能分解海带多糖形成高分子量寡糖、少量低分子量寡糖和极少量葡萄糖。用葡萄糖氧化酶进行的研究表明，1,3-β-葡聚糖的分解产生β型葡萄糖。
