In enzymology, a valine-tRNA ligase (EC 22.214.171.124) is an enzyme that catalyzes the chemical reaction
- ATP + L-valine + tRNAVal AMP + diphosphate + L-valyl-tRNAVal
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).
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:tRNAVal 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.
Structural studies 
As of late 2007, 5 structures have been solved for this class of enzymes, with PDB accession codes 1GAX, 1IVS, 1IYW, 1WK9, and 1WKA.
See also 
- Berg P, Bergmann FH, Ofengand EJ and Dieckmann M (1961). "The enzymic synthesis of amino acyl derivatives of ribonucleic acid I. The mechanism of leucyl-, valyl-, isoleucyl- and methionyl ribonucleic acid formation". J. Biol. Chem. 236: 1726–1734.
- Bergmann FH, Berg P and Dieckmann M (1961). "The enzymic synthesis of amino acyl derivatives of ribonucleic acid II. The preparation of leucyl-, valyl-, isoleucyl- and methionyl ribonucleic acid synthetases from Escherichia coli". J. Biol. Chem. 236: 1735–1740.