Aminoacyl-tRNAs are key components in protein synthesis. They are formed directly by correct acylation of tRNA (by aminoacyl-tRNA synthetases) or indirectly by tRNA-dependent transformation of misacylated tRNAs. The accuracy of aminoacyl-tRNA synthesis is enhanced by a number of further protein-RNA or protein-protein interactions, some of which are restricted to Archaea, and might reflect adaptation mechanisms to diverse conditions.