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).
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.