Substituent effects of an antibody-catalyzed hydrolysis of phenyl esters: further evidence for an acyl-antibody intermediate
作者:Richard A. Gibbs、Patricia A. Benkovic、Kim D. Janda、Richard A. Lerner、Stephen J. Benkovic
DOI:10.1021/ja00035a057
日期:1992.4
The hydrolysis of a series of para-substituted phenyl esters by the monoclonal catalytic antibody NPN43C9 has been investigated. The apparent pK a observed in the k cat /K m -pH profiles shifts from 8.9 (p-nitrophenyl ester) up to a maximum of 9.5 (p-methylphenyl ester). A correlation of the antibody-catalyzed rates of hydrolysis of the esters versus the σ parameter affords a ρ value of 2.3, indicative
已经研究了单克隆催化抗体 NPN43C9 对一系列对位取代苯基酯的水解。在 k cat /K m -pH 曲线中观察到的表观 pK a 从 8.9(对硝基苯酯)移至最大值 9.5(对甲基苯酯)。抗体催化的酯水解速率与 σ 参数的相关性提供 2.3 的 ρ 值,表明水解机制通过中性氮亲核试剂的攻击进行,与一般碱催化的低 ρ 值形成对比水解