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1qam
From Proteopedia
THE STRUCTURE OF THE RRNA METHYLTRANSFERASE ERMC': IMPLICATIONS FOR THE REACTION MECHANISM
Overview
The rRNA methyltransferase ErmC' transfers methyl groups from S -adenosyl-l-methionine to atom N6 of an adenine base within the peptidyltransferase loop of 23 S rRNA, thus conferring antibiotic resistance against a number of macrolide antibiotics. The crystal structures of ErmC' and of its complexes with the cofactor S -adenosyl-l-methionine, the reaction product S-adenosyl-l-homocysteine and the methyltransferase inhibitor Sinefungin, respectively, show that the enzyme undergoes small conformational changes upon ligand binding. Overall, the ligand molecules bind to the protein in a similar mode as observed for other methyltransferases. Small differences between the binding of the amino acid parts of the different ligands are correlated with differences in their chemical structure. A model for the transition-state based on the atomic details of the active site is consistent with a one-step methyl-transfer mechanism and might serve as a first step towards the design of potent Erm inhibitors.
About this Structure
1QAM is a Single protein structure of sequence from Bacillus subtilis. Full crystallographic information is available from OCA.
Reference
The 2.2 A structure of the rRNA methyltransferase ErmC' and its complexes with cofactor and cofactor analogs: implications for the reaction mechanism., Schluckebier G, Zhong P, Stewart KD, Kavanaugh TJ, Abad-Zapatero C, J Mol Biol. 1999 Jun 4;289(2):277-91. PMID:10366505 Page seeded by OCA on Sat May 3 06:04:17 2008
