Orotidine 5'-monophosphate decarboxylase (ODCase) is a key enzyme in the de novo pyrimidine biosynthetic pathway. This pathway is essential for the biosynthesis of building blocks for both DNA and RNA, and thus inhibitors of ODCase could have significant therapeutic value. Despite recent significant advances, it is not understood what factors are important in binding to and catalysis by ODCase. The lack of such knowledge is a critical deficit because understanding these factors is essential to the design of potent inhibitors for this enzyme. Our long-range goal is to understand the catalytic mechanism of ODCase and to design potent inhibitors of ODCase based on the mechanism. The objective of this application, which is a step in pursuit of that goal, is the identification of structural components of the substrate and its analogs that are important for binding and catalysis. The central hypothesis of the application is that the active site is structured to preferentially bind nucleotides with large matched dipole moment (as a result of an overall negative charge around the heterocyclic ring). The rationale for the proposed research is that, once the structural features determining tight binding between the enzyme and nucleotides are identified, novel potent inhibitors can be designed, which could serve as lead compounds in the design of drug candidates. The hypothesis will be tested by pursuing the following two specific aims: 1) Determine how the negative charge on the nucleotide base and the relative positions of the pyrimidine moiety to the phosphoribose moiety affect the binding of substrate analogues;and 2) Determine structural requirement for substrate binding and to eventually identify amino acid residues interacting with the substrate carboxylate group.

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Orotidine 5'-monophosphate decarboxylase (ODCase) is a key enzyme in the de novo pyrimidine biosynthetic pathway. This pathway is essential for the biosynthesis of building blocks for both DNA and RNA. Inhibition of the biosynthesis of these building blocks has been exploited in the development of antiviral, antitumor, and antimalarial drugs.

National Institute of Health (NIH)
National Institute of General Medical Sciences (NIGMS)
Research Enhancement Award (SC1)
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Special Emphasis Panel (ZGM1-MBRS-1 (SC))
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Fabian, Miles
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San Francisco State University
Schools of Arts and Sciences
San Francisco
United States
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Tang, Khanh G; Kent, Greggory T; Erden, Ihsan et al. (2017) cis-?-Bromostyrene derivatives from cinnamic acids via a tandem substitutive bromination-decarboxylation sequence. Tetrahedron Lett 58:3894-3896
Kent, Greggory T; Blackburn, Daniel J; Gonzalez, Joseph R et al. (2016) Convenient synthesis of phosphonohydrazines from arylamines. Tetrahedron Lett 57:2097-2099
McGraw, Kristen M; Bowler, Jeannette T; Ly, Vy T et al. (2016) Reductive debromination of 1,2-dibromides with anisidines. Tetrahedron Lett 57:285-287
Bowler, Jeannette T; Clausen, Caitlin R; Blackburn, Daniel J et al. (2014) Convenient synthesis of N1-substituted orotic acid derivatives. Tetrahedron Lett 55:6465-6466
Bowler, Jeannette T; Wong, Freeman M; Gronert, Scott et al. (2014) Reactivity in the nucleophilic aromatic substitution reactions of pyridinium ions. Org Biomol Chem 12:6175-80
Chen, Yi-Pei; Catbagan, Chad C; Bowler, Jeannette T et al. (2014) Evaluation of benzoic acid derivatives as sirtuin inhibitors. Bioorg Med Chem Lett 24:349-52
Senger, Nicholas A; Bliss, Carly E; Keeffe, James R et al. (2013) Stabilities of Uracil and Pyridone-Based Carbanions: A Systematic Study in the Gas Phase and Solution and Implications for the Mechanism of Orotidine-5'-Monophosphate Decarboxylase. Tetrahedron 69:5287-5292
Senger, Nicholas A; Bowler, Jeannette T; Mercado, Rene S et al. (2013) Improved synthesis of N1-substituted orotic acid derivatives. Tetrahedron Lett 54:4245-4246
Senger, Nicholas A; Bo, Bo; Cheng, Qian et al. (2012) The element effect revisited: factors determining leaving group ability in activated nucleophilic aromatic substitution reactions. J Org Chem 77:9535-40
Tsang, Wing-Yin; Wood, B McKay; Wong, Freeman M et al. (2012) Proton transfer from C-6 of uridine 5'-monophosphate catalyzed by orotidine 5'-monophosphate decarboxylase: formation and stability of a vinyl carbanion intermediate and the effect of a 5-fluoro substituent. J Am Chem Soc 134:14580-94