Valine–tRNA ligase

In enzymology, a valine–tRNA ligase (EC 6.1.1.9) is an enzyme that catalyzes the chemical reaction

ATP + L-valine + tRNA^Val ${\displaystyle \rightleftharpoons }$ AMP + diphosphate + L-valyl-tRNA^Val

The 3 substrates of this enzyme are ATP, L-valine, and tRNA^Val, whereas its 3 products are AMP, diphosphate, and L-valyl-tRNA^Val. In humans, this enzyme is encoded by the genes VARS1 and VARS2.^[1]

This enzyme belongs to the family of ligases, to be specific those forming carbon-oxygen bonds in aminoacyl-tRNA and related compounds. The systematic name of this enzyme class is L-valine:tRNA^Val ligase (AMP-forming). Other names in common use include valyl-tRNA synthetase, valyl-transfer ribonucleate synthetase, valyl-transfer RNA synthetase, valyl-transfer ribonucleic acid synthetase, valine transfer ribonucleate ligase, and valine translase. This enzyme participates in valine, leucine and isoleucine biosynthesis, and aminoacyl-tRNA biosynthesis.