香菇蛋白的分级纯化和结构分析

Fractionation and Structure of Protein from Lentinus edodes

香菇粉经10℃pH10的水提取制备香菇蛋白,得率13.1%,其蛋白含量47.5%,多糖含量24.2%。香菇蛋白经DEAE Sepharose CL-6B柱层析分级得5个级分,收集级分F1、F2、F3、F4,它们都是由蛋白和多糖构成的复合物。Sepharose CL-6B凝胶色谱显示,F2和F4的分子量分布较为均匀,且以蛋白为主,多糖含量很低;F3主要由两个分子量不同的蛋白级分构成,含有一定的多糖;F1中多糖含量较高,蛋白含量较少,且多糖分子量分布均匀。香菇蛋白的分子量主要集中在20kDa～40kDa之间。F1、F3、F4都属于酸性蛋白质,含有除色氨酸之外的7种必需氨基酸,除蛋氨酸含量较低外,其余必需氨基酸含量接近,且赖氨酸含量较高。红外光谱分析表明,香菇蛋白的二级结构主要为α-螺旋和无规卷曲。

Powder of Lentinus edodes was treated with water of 10 ℃ and pH 10 to extract the protein of Lentinus edodes (PLE).The yield of PLE was 13.1%,and its protein content was 47.5% and polysaccharide content was 24.2%.PLE was graded into five fractions by chromatography on a DEAE Sepharose CL-6B Column.Fractions F1,F2,F3 and F4 were collected,which all were the complex of protein and polysaccharide.Gel filtration chromatography of Sepharose CL-6B showed that molecular weight (Mw) distribution of F2 and F4 was sy...