Methionine—tRNA ligase
Template:Infobox enzyme In enzymology, a methionine—tRNA ligase (Template:EnzExplorer) is an enzyme that catalyzes the chemical reaction
- ATP + L-methionine + tRNAMet AMP + diphosphate + L-methionyl-tRNAMet
The 3 substrates of this enzyme are ATP, L-methionine, and tRNA(Met), whereas its 3 products are AMP, diphosphate, and L-methionyl-tRNA(Met).
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-methionine:tRNAMet ligase (AMP-forming). Other names in common use include methionyl-tRNA synthetase, methionyl-transfer ribonucleic acid synthetase, methionyl-transfer ribonucleate synthetase, methionyl-transfer RNA synthetase, methionine translase, and MetRS. This enzyme participates in 3 metabolic pathways: methionine metabolism, selenoamino acid metabolism, and aminoacyl-trna biosynthesis.
Role in oxidative stress
During oxidative stress, methionine—tRNA ligase might be phosphorylated, which results in promiscuity of this enzyme, where it aminoacylates methionine to various non-Met tRNAs. This in turn leads to substitution of amino acids in proteins with methionine, which helps relieve oxidative stress in the cell.[1]
Structural studies
As of late 2007, 21 structures have been solved for this class of enzymes, with PDB accession codes Template:PDB link, Template:PDB link, Template:PDB link, Template:PDB link, Template:PDB link, Template:PDB link, Template:PDB link, Template:PDB link, Template:PDB link, Template:PDB link, Template:PDB link, Template:PDB link, Template:PDB link, Template:PDB link, Template:PDB link, Template:PDB link, Template:PDB link, Template:PDB link, Template:PDB link, Template:PDB link, and Template:PDB link.
References
Further reading
Template:Ligases CO CS and CN Template:Enzymes Template:Portal bar