BIOCATALYSIS IN ORGANIC-SOLVENT SYSTEMS USING THERMOSTABLE ENZYMES - ESTERASE-CATALYZED TRANSESTERIFICATION OF Z-L-TYROSINE PARA-NITROPHENYL ESTER

被引：11

作者：

OWUSU, RK ^{[1
]}

COWAN, DA ^{[1
]}

机构：

[1] UNIV LONDON UNIV COLL,DEPT BIOCHEM,GOWER ST,LONDON WC1E 6BT,ENGLAND

来源：

ENZYME AND MICROBIAL TECHNOLOGY | 1990年 / 12卷 / 05期

关键词：

Esterase; organic solvent catalyses; thermophilic enzyme; transesterification;

D O I：

10.1016/0141-0229(90)90167-O

中图分类号：

Q81 [生物工程学（生物技术）]; Q93 [微生物学];

学科分类号：

071005 ; 0836 ; 090102 ; 100705 ;

摘要：

The esterase-catalysed transesterification of N-carbobenzoxy-l-tyrosine p-nitrophenol ester (Z-Tyrp-NPE) with methanol was studied with water: methanol cosolvent and with dry ethyl acetate as solvent. The crude esterase employed was fully thermostable in both solvents at 44°C. At 88°C esterase activity decreased by 90% in water: methanol (10% v/v) and 30% in dry ethyl acetate after 4 h. The initial rate of transesterification was the same order of magnitude, i.e. 1.7 and 0.95 μmol h-1 unit-1 esterase in the two solvents, respectively. However, Z-TyrpNPE solubility was about 50-fold greater in ethyl acetate compared to the water: methanol cosolvent system, accounting for a 50-fold greater quantity of product formed per experiment in ethyl acetate. © 1990.

引用

页码：374 / 377

页数：4