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Publication Abstract from PubMed

Lysyl-tRNA synthetase is a member of the class II aminoacyl-tRNA synthetases and catalyses the specific aminoacylation of tRNA(Lys). The crystal structure of the constitutive lysyl-tRNA synthetase (LysS) from Escherichia coli has been determined to 2.7 A resolution in the unliganded form and in a complex with the lysine substrate. A comparison between the unliganded and lysine-bound structures reveals major conformational changes upon lysine binding. The lysine substrate is involved in a network of hydrogen bonds. Two of these interactions, one between the alpha-amino group and the carbonyl oxygen of Gly 216 and the other between the carboxylate group and the side chain of Arg 262, trigger a subtle and complicated reorganization of the active site, involving the ordering of two loops (residues 215-217 and 444-455), a change in conformation of residues 393-409, and a rotation of a 4-helix bundle domain (located between motif 2 and 3) by 10 degrees. The result of these changes is a closing up of the active site upon lysine binding.

Structural studies of lysyl-tRNA synthetase: conformational changes induced by substrate binding.,Onesti S, Desogus G, Brevet A, Chen J, Plateau P, Blanquet S, Brick P Biochemistry. 2000 Oct 24;39(42):12853-61. PMID:11041850^[1]

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.