1qaq: Difference between revisions

[[Image:1qaq.jpg|left|200px]]<br /><applet load="1qaq" size="350" color="white" frame="true" align="right" spinBox="true"  

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.

1QAQ is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Bacillus_subtilis Bacillus subtilis] with <scene name='pdbligand=SFG:'>SFG</scene> as [http://en.wikipedia.org/wiki/ligand ligand]. Active as [http://en.wikipedia.org/wiki/rRNA_(adenine-N(6)-)-methyltransferase rRNA (adenine-N(6)-)-methyltransferase], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=2.1.1.48 2.1.1.48] Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1QAQ OCA].  

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