Identification of the major tRNA(Phe) binding domain in the tetrameric structure of cytoplasmic phenylalanyl-tRNA synthetase from baker's yeast.
Native cytoplasmic phenylalanyl-tRNA synthetase from baker's yeast is a tetramer of the alpha 2 beta 2 type. On mild tryptic cleavage it gives rise to a modified alpha 2 beta 2 form that has lost the tRNA(Phe) binding capacity but is still able to activate phenylalanine. In this paper are presented data concerning peptides released by this limited proteolytic conversion as well as those arising from exhaustive tryptic digestion of the truncated beta subunit. Each purified peptide was unambiguously assigned to a unique stretch of the beta subunit amino acid sequence that was recently determined via gene cloning and DNA sequencing. Together with earlier results from affinity labelling studies the present data show that the Lys 172-Ile 173 bond is the unique target of trypsin under mild conditions and that the N-terminal domain of each beta subunit (residues 1-172) contains the major tRNA(Phe) binding sites.
Fasiolo
F
F
Institut de Biologie Moléculaire et Cellulaire du CNRS, Strasbourg, France.
Sanni
A
A
Potier
S
S
Ebel
J P
JP
Boulanger
Y
Y
D000595:Amino Acid Sequence; D000604:Amino Acyl-tRNA Synthetases; D001665:Binding Sites; D008969:Molecular Sequence Data; D015394:Molecular Structure; D010446:Peptide Fragments / Q000032:analysis; D010652:Phenylalanine-tRNA Ligase; D012345:RNA, Transfer, Amino Acid-Specific; D012360:RNA, Transfer, Phe; D012441:Saccharomyces cerevisiae / Q000201:enzymology*
D010446:Peptide Fragments; D012345:RNA, Transfer, Amino Acid-Specific; D012360:RNA, Transfer, Phe; D000604:Amino Acyl-tRNA Synthetases; D010652:Phenylalanine-tRNA Ligase