Chen C Will, Ou-Yang Chao-Chih
Department of Bioengineering, Tatung University, 40 Chungshan Road, 3rd Section, Taipei, Taiwan, Republic of China.
Bioprocess Biosyst Eng. 2004 Oct;26(5):307-13. doi: 10.1007/s00449-004-0367-z.
In the present investigation, beta-galactosidase was solubilized into Aerosol OT (AOT)/isooctane reverse micelles. Kinetic data for the hydrolysis of o-nitrophenyl-beta-D-galactopyranoside (ONPG) at different pH values and molar ratios of water to AOT (Wo) were collected. It was observed that the usual kinetic model used for beta-galactosidase catalysis in aqueous systems failed to represent the experimental data. A bounded water model, however, showed a better correlation between enzymatic activity and Wo. In contrast to the aqueous system, controlling the water concentration in the reverse micelles allows the rate constants for the reaction between water molecules and glycosyl-enzyme complexes to be evaluated.
在本研究中，β-半乳糖苷酶被溶解于气溶胶OT（AOT）/异辛烷反胶束中。收集了在不同pH值和水与AOT的摩尔比（Wo）下对邻硝基苯基-β-D-吡喃半乳糖苷（ONPG）进行水解的动力学数据。结果发现，用于水相体系中β-半乳糖苷酶催化的常规动力学模型无法体现实验数据。然而，一个束缚水模型显示出酶活性与Wo之间有更好的相关性。与水相体系不同，控制反胶束中的水浓度能够评估水分子与糖基-酶复合物之间反应的速率常数。
