1jjc
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Crystal structure at 2.6A resolution of phenylalanyl-tRNA synthetase complexed with phenylalanyl-adenylate in the presence of manganese
OverviewOverview
The crystal structure of phenylalanyl-tRNA synthetase (PheRS) from Thermus, thermophilus, a class II aminoacyl-tRNA synthetase, complexed with, phenylalanyl-adenylate (Phe-AMP) was determined at 2.6 A resolution., Crystals of native PheRS were soaked in a solution containing, phenylalanine and ATP in the presence of Mn(2+) ions. The first step of, the aminoacylation reaction proceeds within the crystals, resulting in, Phe-AMP formation at the active site. Specific recognition of the, phenylalanine portion of the Phe-AMP is achieved by interactions of the, phenyl ring of Phe-AMP with two neighbouring residues, Phealpha258 and, Phealpha260. No manganese ions were observed within the active site; their, role in the formation of the transition state may be assigned to a number, of polar residues and water molecules. In the anomalous Fourier difference, map, a divalent metal ion was detected at the interface of the alpha- and, beta-subunits at a short distance from motif 3 residues participating in, the substrate binding. A sulfate ion, which was identified on the protein, surface, may mediate the interactions of PheRS with DNA. Visible, conformational changes were detected in the active-site area adjacent to, the position of the Phe-AMP, compared with the structure of PheRS, complexed with a synthetic adenylate analogue (phenylalaninyl-adenylate)., Based on the known structures of the substrate-free enzyme and its, complexes with various ligands, a general scheme for the phenylalanylation, mechanism is proposed.
About this StructureAbout this Structure
1JJC is a Protein complex structure of sequences from Thermus thermophilus with MN, SO4 and FA5 as ligands. Active as Phenylalanine--tRNA ligase, with EC number 6.1.1.20 Full crystallographic information is available from OCA.
ReferenceReference
Structure at 2.6 A resolution of phenylalanyl-tRNA synthetase complexed with phenylalanyl-adenylate in the presence of manganese., Fishman R, Ankilova V, Moor N, Safro M, Acta Crystallogr D Biol Crystallogr. 2001 Nov;57(Pt 11):1534-44. Epub 2001, Oct 25. PMID:11679717
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