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从七种食用和药用真菌中筛选出纤维素分解能力较强的灵芝菌株（Ｇａｎｏｄｅｒｍａｌｕｃｉｄｕｍ５００５９），比较了几种不同碳源的固体发酵培养基对灵芝５００５９产内切β－葡聚糖酶（又称羧甲基纤维素酶，ＣＭＣ酶）能力的影响，确定了最佳培养时间为５～６ｄ。通过硫酸铵沉淀、凝胶过滤和离子交换层析初步提纯了灵芝的ＣＭＣ酶，得到三个组分。其中一个组分在ＳＤＳ－ＰＡＧＥ电泳中为一条带，为单亚基分子，分子量为４．５×１０４，等电点为３．２，以ＣＭＣ－Ｎａ为底物的米氏常数（Ｋｍ）为７．２ｇ／Ｌ。该酶活力的最适温度为５０℃，半致死温度约６７℃。该ＣＭＣ酶组分在ｐＨ３．０～６．０范围内稳定，最适ｐＨ约为２．０和４．０。
The Ganoderma lucidum 50059 with strong cellulose decomposition ability was screened from seven kinds of edible and medicinal fungi. The effects of solid fermentation medium with different carbon sources on endo-β-glucanase Called carboxymethyl cellulose, CMC enzyme) ability to determine the best culture time is 5 ~ 6d. CMCase of Ganoderma lucidum was preliminarily purified by ammonium sulfate precipitation, gel filtration and ion-exchange chromatography to obtain three components. One of the components was a band on SDS-PAGE electrophoresis, which was a single subunit with a molecular weight of 4.5 × 104, an isoelectric point of 3.2 and a Michaelis constant (Km) of CMC-Na. 7.2g / L. The enzyme activity of the optimum temperature of 50 ℃, semi-lethal temperature of about 67 ℃. The CMC enzyme components in the pH range of 3.0 to 6.0 stable, the optimum pH is about 2.0 and 4.0.