InterPro domain: IPR025564

This domain is present in aminoacyl-tRNA synthetases (aaRSs), enzymes that couple tRNAs to their cognate amino acids [ 1 ]. aaRSs from cyanobacteria containing the CAAD (for cyanobacterial aminoacyl-tRNA synthetases appended domain) protein domains are localised in the thylakoid membrane. The domain bears two putative transmembrane helices and is present in glutamyl-, isoleucyl-, leucyl-, and valyl-tRNA synthetases, the latter of which has probably recruited the domain more than once during evolution.

1. Intraphylum diversity and complex evolution of cyanobacterial aminoacyl-tRNA synthetases. Mol. Biol. Evol. 25, 2369-89