2pth

Publication Abstract from PubMed

Peptidyl-tRNA hydrolase activity from Escherichia coli ensures the recycling of peptidyl-tRNAs produced through abortion of translation. This activity, which is essential for cell viability, is carried out by a monomeric protein of 193 residues. The structure of crystalline peptidyl-tRNA hydrolase could be solved at 1.2 A resolution. It indicates a single alpha/beta globular domain built around a twisted mixed beta-sheet, similar to the central core of an aminopeptidase from Aeromonas proteolytica. This similarity allowed the characterization by site-directed mutagenesis of several residues of the active site of peptidyl-tRNA hydrolase. These residues, strictly conserved among the known peptidyl-tRNA hydrolase sequences, delineate a channel which, in the crystal, is occupied by the C-end of a neighbouring peptidyl-tRNA hydrolase molecule. Hence, several main chain atoms of three residues belonging to one peptidyl-tRNA hydrolase polypeptide establish contacts inside the active site of another peptidyl-tRNA hydrolase molecule. Such an interaction is assumed to represent the formation of a complex between the enzyme and one product of the catalysed reaction.

Crystal structure at 1.2 A resolution and active site mapping of Escherichia coli peptidyl-tRNA hydrolase.,Schmitt E, Mechulam Y, Fromant M, Plateau P, Blanquet S EMBO J. 1997 Aug 1;16(15):4760-9. PMID:9303320^[1]

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