Enzyme - Serine--tRNA ligase

Alternative Name(s)
  • Seryl-transfer RNA synthetase.
  • Seryl-tRNA synthetase.
  • SerRS.
  • Seryl-transfer ribonucleic acid synthetase.
  • Serine translase.
  • Seryl-transfer ribonucleate synthetase.

Catalytic Activity

ATP + L-serine + tRNA(Sec) = AMP + diphosphate + H(+) + L-seryl-tRNA(Sec)


There are no Cofactors for this Enzyme

Reaction Mechanisms

    Serine-tRNA ligase (EC: exists as monomer and belongs to the aminoacyl-tRNA synthetase class IIa. It catalyses the attachment of serine to tRNA (Ser). It is also able to aminoacylate tRNA (Sec) with serine, to form the misacylated tRNA L-seryl-tRNA (Sec), which will be further converted into selenocysteinyl-tRNA (Sec).

    This enzyme catalyzes two successive transfer reactions. Firstly, it transfers the adenylate from ATP (the first substrate) to the carboxylate of the second substrate, serine, resulting in the formation of seryl-adenylate (intermediate) and the release of the inorganic pyrophosphate. Secondly, it transfers the acyl group from the intermediate to the 3'-OH of tRNA(Ser). The ATP is found in an unusual bent conformation, stabilised by interactions with conserved arginines and three manganese ions.
    Catalytic Residues
    AA Uniprot Uniprot Resid PDB PDB Resid
    Glu P34945 345 1ses 345
    Ser P34945 348 1ses 348
    Arg P34945 386 1ses 386
    Arg P34945 256 1ses 256
    Arg P34945 271 1ses 271

Reaction Parameters

There are no kinetic parameters information for this Enzyme

Associated Proteins

Protein name Organism
Serine--tRNA ligase Escherichia coli (strain K12)
Probable serine--tRNA ligase, cytoplasmic Caenorhabditis elegans
Serine--tRNA ligase, mitochondrial Bovine
Serine--tRNA ligase, chloroplastic/mitochondrial Mouse-ear cress
Type-2 serine--tRNA ligase Methanothermobacter thermautotrophicus (strain ATCC 29096 / DSM 1053 / JCM 10044 / NBRC 100330 / Delta H)