What are the Classes of Aminoacyl tRNA Synthetases?
Aminoacyl tRNA synthetases are divided into two main classes, Class I and Class II, based on their structural motifs and mechanistic properties. Class I aaRSs typically form monomers or dimers and attach the amino acid to the 2'-hydroxyl group of the tRNA. In contrast, Class II aaRSs generally form dimers or tetramers and attach the amino acid to the 3'-hydroxyl group of the tRNA. These structural differences influence their catalytic mechanisms and substrate specificities.
