Carboxylate−Imidazole Cooperativity in Dipeptide-Functionalized Gold Nanoparticles with Esterase-like Activity
作者:Paolo Pengo、Stefano Polizzi、Lucia Pasquato、Paolo Scrimin
DOI:10.1021/ja043547c
日期:2005.2.1
We report here the first example of peptide-functionalized gold nanoparticles hydrolytically active against carboxylate esters. The active units are constituted by His-Phe-OH terminating thiols. The confinement of the catalytic units in the monolayer covering the nanoparticles triggers a cooperative hydrolytic mechanism operative at pH < 7 in which a carboxylate and an imidazolium ion act as general
我们在这里报告了第一个对羧酸酯具有水解活性的肽官能化金纳米粒子的例子。活性单元由His-Phe-OH封端硫醇构成。催化单元在覆盖纳米颗粒的单层中的限制触发了在 pH < 7 时起作用的协同水解机制,其中羧酸盐和咪唑鎓离子分别充当一般碱和一般酸。类似的单体二肽不存在这种机制,这导致在功能性纳米粒子存在的情况下,在低 pH 值下水解过程的速率加速超过 300 倍。