文献类型：期刊文献

英文题名：Effect of organic cosolvent on kinetic resolution of tert-leucine by penicillin G acylase from Kluyvera citrophila

作者：Liu, Shu-Lai[1]; Wei, Dong-Zhi[1]; Song, Qing-Xun[1]; Zhang, Ye-Wang[1]; Wang, Xue-Dong[1]

机构：[1] State Key Lab. of Bioreactor Engineering, East China University of Science and Technology, 130 Meilong Road, Shanghai 200237, China

年份：2006

卷号：28

期号：5

起止页码：285

外文期刊名：Bioprocess and Biosystems Engineering

收录：EI(收录号：2006149802533)

语种：英文

外文关键词：Enzymes - Hydrolysis - Organic solvents - Permittivity - Solutions

摘要：Penicillin G acylase (PGA) from Kluyvera citrophila immobilized on Amberzyml was used for enantioselective hydrolysis of N-phenylacetylated-DL- tert-leucine (N-Phac-DL-Tle) to produce L-tert-leucine (L-Tle). The effects of various organic cosolvents on hydrolysis of N-Phac-DL-Tle have been investigated in aqueous - cosolvent medium. It was found that the rate of PGA-catalyzed reaction was significantly affected by the presence of 2% (v/v) organic cosolvent concentration. The initial rate fell with increasing logP of the cosolvent, but for logP values less than -0.24, the rate was faster than that in purely aqueous medium. Additionally, the relative rate increases with the increase of dielectric constant (Ε) of organic cosolvents. The yields of L-Tle in all aqueous - cosolvent systems were above 95% with the enantiomeric excess (ee) of > 99%. ? Springer-Verlag 2005.