Structure-Guided Mutagenesis Reveals the Catalytic Residue That Controls the Regiospecificity of C6-Indole Prenyltransferases

May 9, 2023

Title

Structure-Guided Mutagenesis Reveals the Catalytic Residue That Controls the Regiospecificity of C6-Indole Prenyltransferases

Author

Aoun, Ahmed R., Nagaraju Mupparapu, Diem N. Nguyen, Tae Ho Kim, Christopher M. Nguyen, Zhengfeiyu Pan, and Sherif I. Elshahawi

Year

2023

Journal

ChemCatChem

Abstract

Indole is a significant structural moiety and functionalization of the C?H bond in indole-containing molecules expands their chemical space, and modifies their properties and/or activities. Indole prenyltransferases (IPTs) catalyze the direct regiospecific installation of prenyl, C5 carbon units, on indole-derived compounds. IPTs have shown relaxed substrate flexibility enabling them to be used as tools for indole functionalization. However, the mechanism by which certain IPTs target a specific carbon position is not fully understood. Herein, we use structure-guided site-directed mutagenesis, in vitro enzymatic reactions, kinetics and structural-elucidation of analogs to verify the key catalytic residues that control the regiospecificity of all characterized regiospecific C6 IPTs. Our results also demonstrate that substitution of PriB_His312 to Tyr leads to the synthesis of analogs prenylated at different positions than C6. This work contributes to understanding of how certain IPTs can access a challenging position in indole-derived compounds.

Instrument

J-1500

Keywords

biocatalysis