1jjc
From Proteopedia
Crystal structure at 2.6A resolution of phenylalanyl-tRNA synthetase complexed with phenylalanyl-adenylate in the presence of manganese
Overview
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 Structure
1JJC is a Protein complex structure of sequences from Thermus thermophilus. Full crystallographic information is available from OCA.
Reference
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 Page seeded by OCA on Fri May 2 21:17:31 2008
