Histidine—tRNA ligase

In enzymology, a histidine-tRNA ligase (EC6.1.1.21) is an enzyme that catalyzes the chemical reaction

The 3 substrates of this enzyme are ATP, L-histidine, and tRNA(His), whereas its 3 products are AMP, diphosphate, and L-histidyl-tRNA(His).

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-histidine:tRNAHis ligase (AMP-forming). Other names in common use include histidyl-tRNA synthetase, histidyl-transfer ribonucleate synthetase, and histidine translase. This enzyme participates in histidine metabolism and aminoacyl-trna biosynthesis.