Clarification of penicillin G acylase reaction mechanism

被引：19

作者：

Kheirolomoom, A

Ardjmand, M

Fazelinia, H

Zakeri, A

机构：

[1] Sharif Univ Technol, Dept Chem Engn, Tehran, Iran

[2] Islamic Azad Univ, Dept Chem Engn, Tehran S Branch, Tehran, Iran

来源：

PROCESS BIOCHEMISTRY | 2001年 / 36卷 / 11期

关键词：

penicillin G acylase; uni bi reaction; bi uni reaction; inhibition; kinetics; reaction mechanism;

D O I：

10.1016/S0032-9592(01)00145-5

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：

The kinetics of the enzymic reaction of penicillin G acylase from a mutant of Escherichia coli ATCC 11105 in forward and reverse directions were studied and the kinetic constants determined. Results show that the enzyme is inhibited by excess substrate, penicillin G (Pen G), and by both products. The non-competitive inhibition by 6-aminopenicillanic acid (B-APA) and competitive inhibition by phenylacetic acid were observed for the ordered uni bi deacylation reaction in the forward direction. The optimum pH value for the reverse acylation reaction was 5.7. The bi uni mechanism for the reverse reaction was investigated and the inhibitory effects of the substrates, 6-APA and phenyl acetic acid, and the product, Pen G, were studied. Result shows that Pen G is the mixed-type inhibitor for the reverse reaction. (C) 2001 Elsevier Science Ltd. All rights reserved.

引用

页码：1095 / 1101

页数：7

共 23 条

[1] ISOLATION AND KINETICS OF PENICILLIN AMIDASE FROM ESCHERICHIA-COLI [J].