2e6y: Difference between revisions

[[Image:2e6y.gif|left|200px]]<br /><applet load="2e6y" size="350" color="white" frame="true" align="right" spinBox="true"  

Orotidine 5'-monophosphate decarboxylase (ODCase) has evolved to catalyze the decarboxylation of orotidine 5'-monophosphate without any covalent intermediates. Active site residues in ODCase are involved in an extensive hydrogen-bonding network. We discovered that 6-iodouridine 5'-monophosphate (6-iodo-UMP) irreversibly inhibits the catalytic activities of ODCases from Methanobacterium thermoautotrophicum and Plasmodium falciparum. Mass spectral analysis of the enzyme-inhibitor complex confirms covalent attachment of the inhibitor to ODCase accompanied by the loss of two protons and the iodo moiety. The X-ray crystal structure (1.6 A resolution) of the complex of the inhibitor and ODCase clearly shows the covalent bond formation with the active site Lys-72 [corrected] residue. 6-Iodo-UMP inhibits ODCase in a time- and concentration-dependent fashion. 6-Iodouridine, the nucleoside form of 6-iodo-UMP, exhibited potent antiplasmodial activity, with IC50s of 4.4 +/- 1.3 microM and 6.2 +/- 0.7 microM against P. falciparum ItG and 3D7 isolates, respectively. 6-Iodouridine 5'-monophosphate is a novel covalent inhibitor of ODCase, and its nucleoside analogue paves the way to a new class of inhibitors against malaria.

2E6Y is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Methanothermobacter_thermautotrophicus Methanothermobacter thermautotrophicus] with <scene name='pdbligand=U5P:'>U5P</scene> and <scene name='pdbligand=GOL:'>GOL</scene> as [http://en.wikipedia.org/wiki/ligands ligands]. Active as [http://en.wikipedia.org/wiki/Orotidine-5'-phosphate_decarboxylase Orotidine-5'-phosphate decarboxylase], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=4.1.1.23 4.1.1.23] Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=2E6Y OCA].  

A potent, covalent inhibitor of orotidine 5'-monophosphate decarboxylase with antimalarial activity., Bello AM, Poduch E, Fujihashi M, Amani M, Li Y, Crandall I, Hui R, Lee PI, Kain KC, Pai EF, Kotra LP, J Med Chem. 2007 Mar 8;50(5):915-21. Epub 2007 Feb 10. PMID:[http://ispc.weizmann.ac.il//pmbin/getpm?pmid=17290979 17290979]

[[Category: Bello, A M.]]

[[Category: Kotra, L P.]]

[[Category: Pai, E F.]]

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