1dv7
CRYSTAL STRUCTURE OF OROTIDINE MONOPHOSPHATE DECARBOXYLASE
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OverviewOverview
Orotidine 5'-monophosphate decarboxylase catalyzes the conversion of, orotidine 5'-monophosphate to uridine 5'-monophosphate, the last step in, biosynthesis of pyrimidine nucleotides. As part of a Structural Genomics, Initiative, the crystal structures of the ligand-free and the6-azauridine, 5'-monophosphate-complexed forms have been determined at 1.8 and 1.5 A, respectively. The protein assumes a TIM-barrel fold with one side of the, barrel closed off and the other side binding the inhibitor. A unique array, of alternating charges (Lys-Asp-Lys-Asp) in the active site prompted us to, apply quantum mechanical and molecular dynamics calculations to analyze, the relative contributions of ground state destabilization and transition, state stabilization to catalysis. The remarkable catalytic power of, orotidine 5'-monophosphate decarboxylase is almost exclusively achieved, via destabilization of the reactive part of the substrate, which is, compensated for by strong binding of the phosphate and ribose groups. The, computational results are consistent with a catalytic mechanism that is, characterized by Jencks's Circe effect.
About this StructureAbout this Structure
1DV7 is a Single protein structure of sequence from Methanothermobacter thermautotrophicus. Active as Orotidine-5'-phosphate decarboxylase, with EC number 4.1.1.23 Full crystallographic information is available from OCA.
ReferenceReference
Electrostatic stress in catalysis: structure and mechanism of the enzyme orotidine monophosphate decarboxylase., Wu N, Mo Y, Gao J, Pai EF, Proc Natl Acad Sci U S A. 2000 Feb 29;97(5):2017-22. PMID:10681441
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