Aminoacyl-tRNA synthetases play a central role in protein synthesis by covalently linking the correct amino acid to the correct tRNA (1). Each aminoacyl-tRNA is then carried to the ribosome where it interacts with the cognate trinucleotide codon on the mRNA and transfers the amino acid onto a growing polypeptide chain. Work on tRNAs and aminoacyltRNA synthetases from bacteria, fungi, plants, an...