Rational Design and Construction of Active-Site Labeled Enzymes

Abstract

With a growing amount of structural information of proteins, deciphering the linkage between the structure and function of these proteins is the next important task in structural genomics. To characterize the function of an enzyme at molecular level, placing a reporter on the active site of an enzyme can be a strategy to examine the dynamics of the interaction between enzyme and its substrate/inhibitor. In this chapter, we describe an approach of active-site labeling of enzyme for this purpose. Provided with the fabrication of a fluorescein-labeled AmpC β-lactamase as an example, we herein depict the methodology of a structure-based selection of the location in an enzyme's active site for bioconjugation and the preparation of the active-site labeled enzyme.

Keywords: Active site; Bioconjugation; Chemical modification; Enzyme; Fluorescence labeling; Protein engineering.