Abstract
Aminoacyl-tRNA synthetases (aaRSs) catalyze ligation of their cognate transfer RNAs (tRNAs) with a specific amino acid, which guarantees the correct protein biosynthesis. The 20 aaRSs are divided into two classes based on the catalytic folds and reaction properties. Up to date, crystal structures of all the 20 members have been reported, and it's time to discuss the structure-function relationships of this enzyme family. Recent genome analyses provide a novel insight, which may unveil the molecular evolution of the 20 members.
