Aminoacyl tRNA synthetase

Anticodon-binding domain of tRNA
leucyl-tRNA synthetase from Thermus thermophilus complexed with a post-transfer editing substrate analogue
Identifiers
SymbolAnticodon_2
PfamPF08264
InterProIPR013155
SCOP21ivs / SCOPe / SUPFAM
Available protein structures:
Pfam  structures / ECOD  
PDBRCSB PDB; PDBe; PDBj
PDBsumstructure summary
DALR anticodon binding domain 1
Thermus thermophilus arginyl-trna synthetase
Identifiers
SymbolDALR_1
PfamPF05746
Pfam clanCL0258
InterProIPR008909
SCOP21bs2 / SCOPe / SUPFAM
Available protein structures:
Pfam  structures / ECOD  
PDBRCSB PDB; PDBe; PDBj
PDBsumstructure summary
DALR anticodon binding domain 2
crystal structure of cysteinyl-tRNA synthetase binary complex with tRNACys
Identifiers
SymbolDALR_2
PfamPF09190
Pfam clanCL0258
InterProIPR015273
Available protein structures:
Pfam  structures / ECOD  
PDBRCSB PDB; PDBe; PDBj
PDBsumstructure summary

An aminoacyl-tRNA synthetase (aaRS or ARS), also called tRNA-ligase, is an enzyme that attaches the appropriate amino acid onto its corresponding tRNA. It does so by catalyzing the transesterification of a specific cognate amino acid or its precursor to one of all its compatible cognate tRNAs to form an aminoacyl-tRNA. In humans, the 20 different types of aa-tRNA are made by the 20 different aminoacyl-tRNA synthetases, one for each amino acid of the genetic code.

This is sometimes called "charging" or "loading" the tRNA with an amino acid. Once the tRNA is charged, a ribosome can transfer the amino acid from the tRNA onto a growing peptide, according to the genetic code. Aminoacyl tRNA therefore plays an important role in RNA translation, the expression of genes to create proteins.