Mechanisms and kinetic assays of aminoacyl-tRNA synthetases

Abstract

Accurate protein synthesis is crucial for life. The key players are aminoacyl-tRNA synthetases (AARSs), which read the genetic code by pairing cognate amino acids and tRNAs. AARSs establish high amino acid selectivity by employing physicochemical limits in molecular recognition. However, chemical and structural resemblance between some amino acids prevents their efficient discrimination by AARSs. In these cases, AARSs hydrolyze the formed non-cognate intermediates or aa-tRNAs to ensure selectivity, establishing complex reaction pathways within the synthetic and editing sites. Understanding AARS mechanisms is crucial for understanding their biology. Here, we review kinetic assays for exploring AARS mechanisms. For each assay, we state the most suitable substrates, product(s) recommended to follow, and, importantly, possible caveats that may lead to the kinetic artefact.

Keywords: AARS editing; AARS kinetic assays; ATP‐PPi exchange; amino acid activation; aminoacyl transfer step; aminoacyl‐tRNA synthetase kinetic artefacts; aminoacyl‐tRNA synthetases; deacylation assay; post‐transfer editing; pre‐transfer editing.