海枣曲霉木聚糖酶的纯化及末端序列研究  

Purification and Partial Amino Acid Sequence of Xylanase from Aspergillus phoenicis

作　　者：江均平[1] 严自正[1] 张树政[1] 

机构地区：[1]中国科学院微生物研究所

出　　处：《生物化学与生物物理学报》1995年第2期159-164,共6页

基　　金：中国科学院资助

摘　　要：海枣曲霉麸曲经水浸提、硫酸铵盐析、凝胶过滤、离子交换层析及ＨＰＬＣ分子排阻层析制备了ＰＡＧＥ．ＳＤＳ－ＰＡＧＥ、ＰＡＧＥ酶谱及ＨＰＬＣ纯的木聚糖酶。木聚精酶经测定不含半胱氨酸及二硫桥结构。用蛋白质序列自动分析仪测定了Ｎ端１４个氨基酸序列；利用羧肽酶Ａ方法测出了Ｃ端６个氨基酸序列。比较不同来源木聚糖酶末端序列，发现海枣曲霉木聚糖酶与６种不同来源的木聚糖酶的Ｎ端序列有很大程度的同源性，并具有特定的通读结构…Ｔｈｒ…Ｇｌｙ…Ｇｌｙ…Ｔｙｒ…。其Ｃ端氨基酸序列也与两种酶有一定的同源性。Xylanase from Aspergillus phoenicis was purified by(NH4)2SO4 fractionation,gel filtration on Sephadex G-100, ion exchange chromatography on DEAESphadex A-50 and HPLC.The enzyme was homogeneous when examined by PAGE,SDS-PAGE,HPLC as well as zymogram on RBB-xylan.No sulphydryl groups and disulphides bridge were detected with DTNB.The sequences of 14 amino acids at N-terminus and 6 amino acids at C-terminus were determined.The amino-terminal sequence showed extensive homology with the sequences of other 6 xylanases and possessed a proposed consensus structure:…Thr…Gly…Gly…Tyr….The carboxyl-terminal sequence was also related to that of other 2 xylanases.

关 键 词：木聚糖酶 糖苷酶 末端序列测定 海枣曲霉 

分 类 号：Q939.506[生物学—微生物学]