ATP + L-phenylalanine + tRNA(Phe) = AMP + diphosphate + H(+) + L-phenylalanyl-tRNA(Phe) Binds 2 magnesium ions per tetramer. Tetramer of two alpha and two beta subunits. Belongs to the phenylalanyl-tRNA synthetase beta subunit family. Type 1 subfamily. Lacks 2 conserved residues that bind magnesium; the aspartate residue in position 464 is replaced by an asparagine and the glutamate residue in position 467 is replaced by a serine residue.