海枣曲霉木聚糖酶Ⅲ糖组成及糖肽结合键研究  

SUGAR COMPOSITION AND GLYCOSYL BONDS OF XYLANASE Ⅲ FROM ASPERGILLUS PHOENICIS

作　　者：江均平[1] 严自正[1] 张树政 

机构地区：[1]中国科学院微生研究所,北京100080

出　　处：《真菌学报》1996年第4期288-291,共4页

基　　金：中国科学院资助项目

摘　　要：海枣曲霉木聚糖酶Ⅲ经PAGE和SDS-PAGE后用Schiff’s试剂染色证明为糖蛋白。经硅胶薄层层析和毛细管气相色谱测定,每分子酶约含4个葡萄糖和1个甘露糖残基。 木聚糖酶Ⅲ经β-消除反应后在241nm处出现一个新的吸收峰。在N_2保护下用含NaBH_4的NaOH溶液处理后,其Ser和Thr减少,相对应丙氨酸增加,并出现α-氨基丁酸。估测酶分户中存在约3个O-糖苷键,糖残墓通过O-糖苷键连接于肽链中丝氨酸或苏氨酸上。Xylanase Ⅲ from Aspergillus phoenicis was identified as glycoprotein on PAGE and SDS-PAGE stained with Schiff's reagent. The carbohydrate composition of the enzyme was analyzed by silica gel thin layer and gas capillary chromatographies. It contained about 4 glucose residues and 1 mannose. Xylanase Ⅲ after β- elimination reaction yielded an absorption peak at 241nm. With the treatment of alkali sodium borohydride under the protection of N2, the serine and threonine residues decreased, while alanine increased and α- amino - n - butyric acid appeared. It was suggested that xylanase Ⅲ had about 3 O - glycosyl bonds and the sugar residues are linked to serine and threonine of peptide chain through O - glycosyl bonds.

关 键 词：海枣曲霉 真菌 木聚糖酶 糖肽结合 

分 类 号：Q949.327.1[生物学—植物学]