secondary structure predictions as well as the presence of both high and kmsks regions , delineating the nucleotide-binding domain and the cooh-terminal helical domain in aminoacyl-trna synthetases of known three-dimensional structure , suggest that the yeast valyl-trna synthetase polypeptide chain can be folded into three domains : an nh2-terminal alpha-helical region followed by a nucleotide-binding topology and a cooh-terminal domain composed of alpha-helices which probably carries major sites in trna binding .
C0002529
aminoacyl-trna synthetases
C0042301
valyl-trna synthetase