Cloning and sequence analysis of the phenylalanyl-tRNA synthetase genes (pheST) from Thermus thermophilus.

While crystals suitable for X-ray diffraction analyses are available of phenylalanyl-tRNA synthetase (PheRS) from the thermophilic bacterium Thermus thermophilus, neither the primary structure of its constituent alpha and beta subunits nor the nucleotide sequence of the corresponding pheS and pheT genes were known. Using specific oligonucleotides of conserved pheS regions that were adapted to the T. thermophilus codon usage, we identified, cloned and subsequently sequenced the pheST genes of this bacterium. The sequences reported here will greatly aid in the three-dimensional structure determination of T. thermophilus PheRS, a heterotetrameric (alpha 2 beta 2), class II aminoacyl-tRNA synthetase.