catalytic core domain of isoleucyl-tRNA synthetases
Isoleucine amino-acyl tRNA synthetases (IleRS) catalytic core domain . This class I enzyme is a monomer which aminoacylates the 2'-OH of the nucleotide at the 3' of the appropriate tRNA. The core domain is based on the Rossman fold and is responsible for the ATP-dependent formation of the enzyme bound aminoacyl-adenylate. It contains the characteristic class I HIGH and KMSKS motifs, which are involved in ATP binding. IleRS has an insertion in the core domain, which is subject to both deletions and rearrangements. This editing region hydrolyzes mischarged cognate tRNAs and thus prevents the incorporation of chemically similar amino acids.