Glutamic acid 160 is the acid-base catalyst of β-xylosidase from Bacillus stearothermophilus T-6:: a family 39 glycoside hydrolase

被引：38

作者：

Bravman, T

Mechaly, A

Shulami, S

Belakhov, V

Baasov, T

Shoham, G

Shoham, Y ^{[1
]}

机构：

[1] Technion Israel Inst Technol, Dept Food Engn & Biotechnol, IL-32000 Haifa, Israel

[2] Technion Israel Inst Technol, Dept Chem, IL-32000 Haifa, Israel

[3] Technion Israel Inst Technol, Inst Catalysis Sci & Technol, IL-32000 Haifa, Israel

[4] Hebrew Univ Jerusalem, Dept Inorgan Chem, IL-91904 Jerusalem, Israel

[5] Hebrew Univ Jerusalem, Lab Struct Chem & Biol, IL-91904 Jerusalem, Israel

来源：

FEBS LETTERS | 2001年 / 495卷 / 1-2期

基金：

以色列科学基金会;

关键词：

beta-xylosidase; glycoside hydrolase family 39; acid-base catalyst; mechanism; Bacillus stearothermophilus;

D O I：

10.1016/S0014-5793(01)02371-7

中图分类号：

Q5 [生物化学]; Q7 [分子生物学];

学科分类号：

071010 ; 081704 ;

摘要：

A beta -xylosidase from Bacillus stearothermophilus T-6 was cloned, overexpressed in Escherichia coli and purified to homogencity. Based on sequence alignment, the enzyme belongs to family 39 glycoside hydrolases, which itself forms part of the wider GH-A dan. The conserved Glu160 rr:as proposed as the acid-base catalyst. An E160A mutant was constructed and subjected to steady state and pre-steady state kinetic analysis together with azide rescue and pll activity profiles. The observed results support the assignment of Glu160 as the acid-base catalytic residue. (C) 2001 Published by Elsevier Science B.V, on behalf of the Federation of European Biochemical Societies.

引用

页码：115 / 119

页数：5

共 22 条

[1] Gapped BLAST and PSI-BLAST: a new generation of protein database search programs [J].