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2e6y
From Proteopedia
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Covalent complex of orotidine 5'-monophosphate decarboxylase (ODCase) with 6-Iodo-UMP
Overview
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-42 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 muM and 6.2 +/- 0.7 muM 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.
About this Structure
2E6Y is a Single protein structure of sequence from Methanothermobacter thermautotrophicus with U5P and GOL as ligands. Active as Orotidine-5'-phosphate decarboxylase, with EC number 4.1.1.23 Full crystallographic information is available from OCA.
Reference
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):915-921. Epub 2007 Feb 10. PMID:17290979
Page seeded by OCA on Wed Nov 21 09:58:13 2007
