Phenylalanine—tRNA ligase

Ferredoxin-fold anticodon binding domain
the crystal structure of phenylalanyl-tRNA synthetase from Thermus thermophilus complexed with cognate tRNAPhe
Identifiers
Symbol	FDX-ACB
Pfam	PF03147
InterPro	IPR005121
SCOP2	1pys / SCOPe / SUPFAM
Available protein structures: Pfam   structures / ECOD   PDB RCSB PDB; PDBe; PDBj PDBsum structure summary

In enzymology, a phenylalanine—tRNA ligase (EC 6.1.1.20) is an enzyme that catalyzes the chemical reaction

ATP + L-phenylalanine + tRNA^Phe ${\displaystyle \rightleftharpoons }$ AMP + diphosphate + L-phenylalanyl-tRNA^Phe

The 3 substrates of this enzyme are ATP, L-phenylalanine, and tRNA^Phe, whereas its 3 products are AMP, diphosphate, and L-phenylalanyl-tRNA^Phe.

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-phenylalanine:tRNAPhe ligase (AMP-forming). Other names in common use include phenylalanyl-tRNA synthetase, phenylalanyl-transfer ribonucleate synthetase, phenylalanine-tRNA synthetase, phenylalanyl-transfer RNA synthetase, phenylalanyl-tRNA ligase, phenylalanyl-transfer RNA ligase, L-phenylalanyl-tRNA synthetase, and phenylalanine translase. This enzyme participates in phenylalanine, tyrosine and tryptophan biosynthesis and aminoacyl-tRNA biosynthesis.

Phenylalanine-tRNA synthetase (PheRS) is known to be among the most complex enzymes of the aaRS (Aminoacyl-tRNA synthetase) family. Bacterial and mitochondrial PheRSs share a ferredoxin-fold anticodon binding (FDX-ACB) domain, which represents a canonical double split alpha+beta motif having no insertions. The FDX-ACB domain displays a typical RNA recognition fold (RRM) formed by the four-stranded antiparallel beta sheet, with two helices packed against it.^{[1][2][3][4][5]}

As of late 2007, 10 structures have been solved for this class of enzymes, with PDB accession codes 1B70, 1B7Y, 1EIY, 1JJC, 1PYS, 2AKW, 2ALY, 2AMC, 2CXI, and 2IY5.

• Stulberg MP (1967). "The isolation and properties of phenylalanyl ribonucleic acid synthetase from Escherichia coli B". J. Biol. Chem. 242 (5): 1060–4. doi:10.1016/S0021-9258(18)96232-0. PMID 5335910.