Construction of an aptamer-conjuncted molecular artificial enzyme with enhanced activity and selectivity

Abstract

Although molecular artificial enzymes have displayed tremendous potential in many homogeneous reactions, their low catalytic selectivity is still a challenge. In this study, an aptamer strategy was developed to construct a molecular artificial enzyme (Apt-Tpy(Fe)) through the covalent conjunction of the catalytic site Tpy(Fe) onto the aptamer of CV which provides the specific binding site for CV. The obtained Apt-Tpy(Fe) appeared enhanced catalytic ability toward CV and obvious catalytic suppression toward other substrate analogues. This performance therefore brings about a superior catalytic preference toward CV. Moreover, based on computer simulation, the structure-function relationship of Apt-Tpy(Fe) was investigated, revealing that the affinity of aptamer to CV as well as the orientation between catalytic site and substrate binding site decide the catalytic performance of Apt-Tpy(Fe) toward CV. This work provides a promising method for developing molecular catalyst with enzyme-like activity and selectivity.