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Yangxing S, Yanzhi L, Yanlai C, Nengzhong W, Shaohua X, Mingguo L, Hui Y. Research Advances in Functional Group-Directed Stereoselective Glycosylation. CHINESE J ORG CHEM 2022. [DOI: 10.6023/cjoc202204050] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
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2
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Manhas A, Dubey S, Jha PC. A profound computational study to prioritize the natural compound inhibitors against the P. falciparum orotidine-5-monophosphate decarboxylase enzyme. J Biomol Struct Dyn 2019; 38:2704-2716. [DOI: 10.1080/07391102.2019.1644197] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Affiliation(s)
- Anu Manhas
- School of Chemical Sciences, Central University of Gujarat, Gandhinagar, Gujarat, India
| | - Saikat Dubey
- Centre for Applied Chemistry, Central University of Gujarat, Gandhinagar, Gujarat, India
| | - Prakash C. Jha
- Centre for Applied Chemistry, Central University of Gujarat, Gandhinagar, Gujarat, India
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3
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Shabeer M, Barbosa LCA, Karak M, Coelho ACS, Takahashi JA. Thiobarbiturates as potential antifungal agents to control human infections caused by Candida and Cryptococcus species. Med Chem Res 2018. [DOI: 10.1007/s00044-017-2126-0] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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4
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Slusarczyk M, Ferla S, Brancale A, McGuigan C. Synthesis and biological evaluation of 6-substituted-5-fluorouridine ProTides. Bioorg Med Chem 2017; 26:551-565. [PMID: 29277307 DOI: 10.1016/j.bmc.2017.11.037] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2017] [Revised: 11/21/2017] [Accepted: 11/23/2017] [Indexed: 11/29/2022]
Abstract
A new family of thirteen phosphoramidate prodrugs (ProTides) of different 6-substituted-5-fluorouridine nucleoside analogues were synthesized and evaluated as potential anticancer agents. In addition, antiviral activity against Chikungunya (CHIKV) virus was evaluated using a cytopathic effect inhibition assay. Although a carboxypeptidase Y assay supported a putative mechanism of activation of ProTides built on 5-fluorouridine with such C6-modifications, the Hint docking studies revealed a compromised substrate-activity for the Hint phosphoramidase-type enzyme that is likely responsible for phosphoramidate bioactivation through P-N bond cleavage and free nucleoside 5'-monophosphate delivery. Our observations may support and explain to some extent the poor in vitro biological activity generally demonstrated by the series of 6-substituted-5-fluorouridine phosphoramidates (ProTides) and will be of guidance for the design of novel phosphoramidate prodrugs.
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Affiliation(s)
- Magdalena Slusarczyk
- School of Pharmacy and Pharmaceutical Sciences, Cardiff University, Cardiff, King Edward VII Avenue, Cardiff CF10 3NB, UK.
| | - Salvatore Ferla
- School of Pharmacy and Pharmaceutical Sciences, Cardiff University, Cardiff, King Edward VII Avenue, Cardiff CF10 3NB, UK
| | - Andrea Brancale
- School of Pharmacy and Pharmaceutical Sciences, Cardiff University, Cardiff, King Edward VII Avenue, Cardiff CF10 3NB, UK
| | - Christopher McGuigan
- School of Pharmacy and Pharmaceutical Sciences, Cardiff University, Cardiff, King Edward VII Avenue, Cardiff CF10 3NB, UK
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5
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Blackburn DJ, Kent GT, Wu W. Regiospecific synthesis of 6-halouridine derivatives: An effective method for coupling sterically hindered pyrimidine bases to ribose. Tetrahedron Lett 2017. [DOI: 10.1016/j.tetlet.2017.02.063] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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6
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Ogungbe IV, Setzer WN. The Potential of Secondary Metabolites from Plants as Drugs or Leads against Protozoan Neglected Diseases-Part III: In-Silico Molecular Docking Investigations. Molecules 2016; 21:E1389. [PMID: 27775577 PMCID: PMC6274513 DOI: 10.3390/molecules21101389] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2016] [Revised: 10/06/2016] [Accepted: 10/12/2016] [Indexed: 12/11/2022] Open
Abstract
Malaria, leishmaniasis, Chagas disease, and human African trypanosomiasis continue to cause considerable suffering and death in developing countries. Current treatment options for these parasitic protozoal diseases generally have severe side effects, may be ineffective or unavailable, and resistance is emerging. There is a constant need to discover new chemotherapeutic agents for these parasitic infections, and natural products continue to serve as a potential source. This review presents molecular docking studies of potential phytochemicals that target key protein targets in Leishmania spp., Trypanosoma spp., and Plasmodium spp.
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Affiliation(s)
- Ifedayo Victor Ogungbe
- Department of Chemistry and Biochemistry, Jackson State University, Jackson, MS 39217, USA.
| | - William N Setzer
- Department of Chemistry, University of Alabama in Huntsville, Huntsville, AL 35899, USA.
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7
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NMR-based conformational analysis of 2′,6-disubstituted uridines and antiviral evaluation of new phosphoramidate prodrugs. Bioorg Med Chem 2015. [DOI: 10.1016/j.bmc.2015.07.003] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
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8
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Fujihashi M, Mnpotra JS, Mishra RK, Pai EF, Kotra LP. Orotidine Monophosphate Decarboxylase--A Fascinating Workhorse Enzyme with Therapeutic Potential. J Genet Genomics 2015; 42:221-34. [PMID: 26059770 DOI: 10.1016/j.jgg.2015.04.005] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/26/2014] [Revised: 04/13/2015] [Accepted: 04/15/2015] [Indexed: 10/23/2022]
Abstract
Orotidine 5'-monophosphate decarboxylase (ODCase) is known as one of the most proficient enzymes. The enzyme catalyzes the last reaction step of the de novo pyrimidine biosynthesis, the conversion from orotidine 5'-monophosphate (OMP) to uridine 5'-monophosphate. The enzyme is found in all three domains of life, Bacteria, Eukarya and Archaea. Multiple sequence alignment of 750 putative ODCase sequences resulted in five distinct groups. While the universally conserved DxKxxDx motif is present in all the groups, depending on the groups, several characteristic motifs and residues can be identified. Over 200 crystal structures of ODCases have been determined so far. The structures, together with biochemical assays and computational studies, elucidated that ODCase utilized both transition state stabilization and substrate distortion to accelerate the decarboxylation of its natural substrate. Stabilization of the vinyl anion intermediate by a conserved lysine residue at the catalytic site is considered the largest contributing factor to catalysis, while bending of the carboxyl group from the plane of the aromatic pyrimidine ring of OMP accounts for substrate distortion. A number of crystal structures of ODCases complexed with potential drug candidate molecules have also been determined, including with 6-iodo-uridine, a potential antimalarial agent.
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Affiliation(s)
- Masahiro Fujihashi
- Department of Chemistry, Graduate School of Science, Kyoto University, Sakyo-ku, Kyoto, 606-8502, Japan
| | - Jagjeet S Mnpotra
- Department of Chemistry & Biochemistry, The University of North Carolina at Greensboro, Greensboro, NC, 27412, USA
| | - Ram Kumar Mishra
- Center for Molecular Design and Preformulations, and Toronto General Research Institute, University Health Network, Toronto, Ontario, M5G 1L7, Canada
| | - Emil F Pai
- Department of Biochemistry, University of Toronto, Toronto, Ontario, M5S 1A8, Canada; Department of Medical Biophysics, University of Toronto, Toronto, Ontario, M5G 1L7, Canada; Department of Molecular Genetics, University of Toronto, Toronto, Ontario, M5S 1A8, Canada; Princess Margaret Cancer Center, University Health Network, Toronto, Ontario, M5G 1L7, Canada
| | - Lakshmi P Kotra
- Center for Molecular Design and Preformulations, and Toronto General Research Institute, University Health Network, Toronto, Ontario, M5G 1L7, Canada; Department of Pharmaceutical Sciences, Leslie Dan Faculty of Pharmacy, University of Toronto, Toronto, Ontario, M5S 3M2, Canada.
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9
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Identification of novel class of falcipain-2 inhibitors as potential antimalarial agents. Bioorg Med Chem 2015; 23:2221-40. [DOI: 10.1016/j.bmc.2015.02.062] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2014] [Revised: 02/16/2015] [Accepted: 02/26/2015] [Indexed: 11/18/2022]
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10
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Kim EK, Krishnamurthy R. Synthesis of orotidine by intramolecular nucleosidation. Chem Commun (Camb) 2015; 51:5618-21. [DOI: 10.1039/c5cc00111k] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
An intramolecular nucleosidation approach, using orotate as a leaving group, provides easy access to orotidine in high yields.
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Affiliation(s)
- E.-K. Kim
- Department of Chemistry
- The Scripps Research Institute
- California
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11
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Imprasittichail W, Roytrakul S, Krungkrai SR, Krungkrail J. A unique insertion of low complexity amino acid sequence underlies protein-protein interaction in human malaria parasite orotate phosphoribosyltransferase and orotidine 5'-monophosphate decarboxylase. ASIAN PAC J TROP MED 2014; 7:184-92. [PMID: 24507637 DOI: 10.1016/s1995-7645(14)60018-3] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2013] [Revised: 09/15/2013] [Accepted: 01/15/2014] [Indexed: 11/17/2022] Open
Abstract
OBJECTIVE To investigate the multienzyme complex formation of human malaria parasite Plasmodium falciparum (P. falciparum) orotate phosphoribosyltransferase (OPRT) and orotidine 5'-monophosphate decarboxylase (OMPDC), the fifth and sixth enzyme of the de novo pyrimidine biosynthetic pathway. Previously, we have clearly established that the two enzymes in the malaria parasite exist physically as a heterotetrameric (OPRT)2(OMPDC)2 complex containing two subunits each of OPRT and OMPDC, and that the complex have catalytic kinetic advantages over the monofunctional enzyme. METHODS Both enzymes were cloned and expressed as recombinant proteins. The protein-protein interaction in the enzyme complex was identified using bifunctional chemical cross-linker, liquid chromatography-mass spectrometric analysis and homology modeling. RESULTS The unique insertions of low complexity region at the α 2 and α 5 helices of the parasite OMPDC, characterized by single amino acid repeat sequence which was not found in homologous proteins from other organisms, was located on the OPRT-OMPDC interface. The structural models for the protein-protein interaction of the heterotetrameric (OPRT)2(OMPDC)2 multienzyme complex were proposed. CONCLUSIONS Based on the proteomic data and structural modeling, it is surmised that the human malaria parasite low complexity region is responsible for the OPRT-OMPDC interaction. The structural complex of the parasite enzymes, thus, represents an efficient functional kinetic advantage, which in line with co-localization principles of evolutional origin, and allosteric control in protein-protein-interactions.
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Affiliation(s)
- Waranya Imprasittichail
- Department of Biochemistry, Faculty of Medicine, Chulalongkorn University, Bangkok 10330, Thailand
| | - Sittiruk Roytrakul
- National Center for Genetic Engineering and Biotechnology, Pathumthani 12120, Thailand
| | - Sudaratana R Krungkrai
- Unit of Biochemistry, Department of Medical Science, Faculty of Science, Rangsit University, Pathumthani 12000, Thailand
| | - Jerapan Krungkrail
- Department of Biochemistry, Faculty of Medicine, Chulalongkorn University, Bangkok 10330, Thailand.
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12
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Jamshidi S, Jalili S, Rafii-Tabar H. Study of orotidine 5'-monophosphate decarboxylase in complex with the top three OMP, BMP, and PMP ligands by molecular dynamics simulation. J Biomol Struct Dyn 2014; 33:404-17. [PMID: 24559040 DOI: 10.1080/07391102.2014.881303] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
Catalytic mechanism of orotidine 5'-monophosphate decarboxylase (OMPDC), one of the nature most proficient enzymes which provides large rate enhancement, has not been fully understood yet. A series of 30 ns molecular dynamics (MD) simulations were run on X-ray structure of the OMPDC from Saccharomyces cerevisiae in its free form as well as in complex with different ligands, namely 1-(5'-phospho-D-ribofuranosyl) barbituric acid (BMP), orotidine 5'-monophosphate (OMP), and 6-phosphonouridine 5'-monophosphate (PMP). The importance of this biological system is justified both by its high rate enhancement and its potential use as a target in chemotherapy. This work focuses on comparing two physicochemical states of the enzyme (protonated and deprotonated Asp91) and three ligands (substrate OMP, inhibitor, and transition state analog BMP and substrate analog PMP). Detailed analysis of the active site geometry and its interactions is properly put in context by extensive comparison with relevant experimental works. Our overall results show that in terms of hydrogen bond occupancy, electrostatic interactions, dihedral angles, active site configuration, and movement of loops, notable differences among different complexes are observed. Comparison of the results obtained from these simulations provides some detailed structural data for the complexes, the enzyme, and the ligands, as well as useful insights into the inhibition mechanism of the OMPDC enzyme. Furthermore, these simulations are applied to clarify the ambiguous mechanism of the OMPDC enzyme, and imply that the substrate destabilization and transition state stabilization contribute to the mechanism of action of the most proficient enzyme, OMPDC.
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Affiliation(s)
- Shirin Jamshidi
- a Faculty of Medicine, Department of Medical Physics and Biomedical Engineering , Shahid Beheshti University of Medical Sciences , Evin, Tehran , Iran
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13
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Abstract
ODCase is a highly proficient enzyme responsible for the decarboxylation of orotidine monophosphate to generate uridine monophosphate. ODCase has attracted early attention due to its interesting mechanism of catalysis. In order to exploit therapeutic advantages due to the inhibition of ODCase, one must have selective inhibitors of this enzyme from the pathogen, or a dysregulated molecular mechanism involving ODCase. ODCase inhibitors have potential applications as anticancer agents, antiviral agents, antimalarial agents and potentially act against other parasitic diseases. A variety of C6-substituted uridine monophosphate derivatives have shown excellent inhibition of ODCase. 6-iodouridine is a potent inhibitor of the malaria parasite, and its monophosphate form covalently inhibits ODCase. A variety of inhibitors of ODCase with potential applications as therapeutic agents are discussed in this review.
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14
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Fujihashi M, Ishida T, Kuroda S, Kotra LP, Pai EF, Miki K. Substrate distortion contributes to the catalysis of orotidine 5'-monophosphate decarboxylase. J Am Chem Soc 2013; 135:17432-43. [PMID: 24151964 PMCID: PMC3949427 DOI: 10.1021/ja408197k] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Orotidine 5'-monophosphate decarboxylase (ODCase) accelerates the decarboxylation of orotidine 5'-monophosphate (OMP) to uridine 5'-monophosphate (UMP) by 17 orders of magnitude. Eight new crystal structures with ligand analogues combined with computational analyses of the enzyme's short-lived intermediates and the intrinsic electronic energies to distort the substrate and other ligands improve our understanding of the still controversially discussed reaction mechanism. In their respective complexes, 6-methyl-UMP displays significant distortion of its methyl substituent bond, 6-amino-UMP shows the competition between the K72 and C6 substituents for a position close to D70, and the methyl and ethyl esters of OMP both induce rotation of the carboxylate group substituent out of the plane of the pyrimidine ring. Molecular dynamics and quantum mechanics/molecular mechanics computations of the enzyme-substrate complex also show the bond between the carboxylate group and the pyrimidine ring to be distorted, with the distortion contributing a 10-15% decrease of the ΔΔG(⧧) value. These results are consistent with ODCase using both substrate distortion and transition-state stabilization, primarily exerted by K72, in its catalysis of the OMP decarboxylation reaction.
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Affiliation(s)
- Masahiro Fujihashi
- Department of Chemistry, Graduate School of Science, Kyoto University, Sakyo-ku, Kyoto, 606-8502, Japan
| | - Toyokazu Ishida
- Nanosystem Research Institute (NRI), National Institute of Advanced Industrial Science and Technology (AIST), Tsukuba Central 2, 1-1-1 Umezono, Tsukuba 305-8568, Japan
| | - Shingo Kuroda
- Department of Chemistry, Graduate School of Science, Kyoto University, Sakyo-ku, Kyoto, 606-8502, Japan
| | - Lakshmi P. Kotra
- Center for Molecular Design and Preformulations and Division of Cell & Molecular Biology, Toronto General Research Institute/University Health Network, Toronto, ON, Canada M5G 1L7
- Departments of Pharmaceutical Sciences and Chemistry, McLaughlin Center for Molecular Medicine, University of Toronto, Canada M5S 3M2
| | - Emil F. Pai
- Center for Molecular Design and Preformulations and Division of Cell & Molecular Biology, Toronto General Research Institute/University Health Network, Toronto, ON, Canada M5G 1L7
- The Campbell Family Cancer Research Institute, Ontario Cancer Institute/University Health Network & Departments of Biochemistry, Medical Biophysics, and Molecular Genetics, University of Toronto, Toronto, ON, Canada M5G 1L7
| | - Kunio Miki
- Department of Chemistry, Graduate School of Science, Kyoto University, Sakyo-ku, Kyoto, 606-8502, Japan
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15
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Shih YC, Yang YY, Lin CC, Chien TC. Synthesis of 6-alkyluridines from 6-cyanouridine via zinc(II) chloride-catalyzed nucleophilic substitution with alkyl Grignard reagents. J Org Chem 2013; 78:4027-36. [PMID: 23535022 DOI: 10.1021/jo400364p] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
6-Cyanouracil derivatives underwent a direct nucleophilic substitution reaction with alkyl Grignard reagents in the presence of zinc(II) chloride as a catalyst to form the corresponding 6-alkyluracils. This methodology is applicable to sugar-protected 6-cyanouridine and 6-cyano-2'-deoxyuridine without the protection at the N(3)-imide and provides a facile and general access to versatile 6-alkyluracil and 6-alkyluridine derivatives.
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Affiliation(s)
- Yu-Chiao Shih
- Department of Chemistry, National Taiwan Normal University, Taipei 11677, Taiwan
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16
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Crandall IE, Wasilewski E, Bello AM, Mohmmed A, Malhotra P, Pai EF, Kain KC, Kotra LP. Antimalarial Activities of 6-Iodouridine and Its Prodrugs and Potential for Combination Therapy. J Med Chem 2013; 56:2348-58. [DOI: 10.1021/jm301678j] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Ian E. Crandall
- Department of Pharmaceutical
Sciences, Leslie Dan Faculty of Pharmacy, University of Toronto, Toronto, Ontario, M5S 3M2, Canada
| | - Ewa Wasilewski
- Center for Molecular Design
and Preformulations, Toronto General Research Institute, University Health Network, 5-356 TMDT/MaRS, 101 College
Street, Toronto, Ontario, M5G 1L7, Canada
| | - Angelica M. Bello
- Department of Pharmaceutical
Sciences, Leslie Dan Faculty of Pharmacy, University of Toronto, Toronto, Ontario, M5S 3M2, Canada
- Center for Molecular Design
and Preformulations, Toronto General Research Institute, University Health Network, 5-356 TMDT/MaRS, 101 College
Street, Toronto, Ontario, M5G 1L7, Canada
| | - Asif Mohmmed
- International Center for Genetic Engineering and Biotechnology, Aruna Asaf
Ali Marg, New Delhi 110 067, India
| | - Pawan Malhotra
- International Center for Genetic Engineering and Biotechnology, Aruna Asaf
Ali Marg, New Delhi 110 067, India
| | - Emil F. Pai
- Ontario Cancer Institute, Campbell Family Cancer Research Institute, Toronto
Medical Discoveries Tower, 101 College Street, Toronto, Ontario, M5G
1L7, Canada
- Departments
of Medical Biophysics,
Biochemistry, and Molecular Genetics, University of Toronto, 1 King’s College Circle, Toronto, Ontario, M5S 1A8, Canada
| | - Kevin C. Kain
- McLaughlin Center for Molecular Medicine
and Department of Medicine, University of Toronto, Toronto, Ontario, Canada
- McLaughlin-Rotman Center for Global Health, Toronto General and Western Hospital Foundation, Toronto Medical Discoveries Tower, 101 College Street, Toronto,
Ontario, M5G 1L7, Canada
| | - Lakshmi P. Kotra
- Department of Pharmaceutical
Sciences, Leslie Dan Faculty of Pharmacy, University of Toronto, Toronto, Ontario, M5S 3M2, Canada
- Center for Molecular Design
and Preformulations, Toronto General Research Institute, University Health Network, 5-356 TMDT/MaRS, 101 College
Street, Toronto, Ontario, M5G 1L7, Canada
- McLaughlin Center for Molecular Medicine
and Department of Medicine, University of Toronto, Toronto, Ontario, Canada
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Fujihashi M, Mito K, Pai EF, Miki K. Atomic resolution structure of the orotidine 5'-monophosphate decarboxylase product complex combined with surface plasmon resonance analysis: implications for the catalytic mechanism. J Biol Chem 2013; 288:9011-6. [PMID: 23395822 DOI: 10.1074/jbc.m112.427252] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Orotidine 5'-monophosphate decarboxylase (ODCase) accelerates the decarboxylation of its substrate by 17 orders of magnitude. One argument brought forward against steric/electrostatic repulsion causing substrate distortion at the carboxylate substituent as part of the catalysis has been the weak binding affinity of the decarboxylated product (UMP). The crystal structure of the UMP complex of ODCase at atomic resolution (1.03 Å) shows steric competition between the product UMP and the side chain of a catalytic lysine residue. Surface plasmon resonance analysis indicates that UMP binds 5 orders of magnitude more tightly to a mutant in which the interfering side chain has been removed than to wild-type ODCase. These results explain the low affinity of UMP and counter a seemingly very strong argument against a contribution of substrate distortion to the catalytic reaction mechanism of ODCase.
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Affiliation(s)
- Masahiro Fujihashi
- Department of Chemistry, Graduate School of Science, Kyoto University, Sakyo-ku, Kyoto 606-8502, Japan
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18
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19
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Purohit MK, Poduch E, Wei LW, Crandall IE, To T, Kain KC, Pai EF, Kotra LP. Novel cytidine-based orotidine-5'-monophosphate decarboxylase inhibitors with an unusual twist. J Med Chem 2012; 55:9988-97. [PMID: 22991951 DOI: 10.1021/jm301176r] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Orotidine-5'-monophosphate decarboxylase (ODCase) is an interesting enzyme with an unusual catalytic activity and a potential drug target in Plasmodium falciparum, which causes malaria. ODCase has been shown to exhibit unusual and interesting interactions with a variety of nucleotide ligands. Cytidine-5'-monophosphate (CMP) is a poor ligand of ODCase, and CMP binds to the active site of ODCase with an unusual orientation and conformation. We designed N3- and N4-modified CMP derivatives as novel ligands to ODCase. These novel CMP derivatives and their corresponding nucleosides were evaluated against Plasmodium falciparum ODCase and parasitic cultures, respectively. These derivatives exhibited improved inhibition of the enzyme catalytic activity, displayed interesting binding conformations and unusual molecular rearrangements of the ligands. These findings with the modified CMP nucleotides underscored the potential of transformation of poor ligands to ODCase into novel inhibitors of this drug target.
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Affiliation(s)
- Meena K Purohit
- Center for Molecular Design and Preformulations, Toronto General Research Institute, University Health Network, Toronto, Ontario M5G 1L7, Canada
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20
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Bazzani S, Hoppe A, Holzhütter HG. Network-based assessment of the selectivity of metabolic drug targets in Plasmodium falciparum with respect to human liver metabolism. BMC SYSTEMS BIOLOGY 2012; 6:118. [PMID: 22937810 PMCID: PMC3543272 DOI: 10.1186/1752-0509-6-118] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/28/2012] [Accepted: 07/23/2012] [Indexed: 11/10/2022]
Abstract
Background The search for new drug targets for antibiotics against Plasmodium falciparum, a major cause of human deaths, is a pressing scientific issue, as multiple resistance strains spread rapidly. Metabolic network-based analyses may help to identify those parasite’s essential enzymes whose homologous counterparts in the human host cells are either absent, non-essential or relatively less essential. Results Using the well-curated metabolic networks PlasmoNet of the parasite Plasmodium falciparum and HepatoNet1 of the human hepatocyte, the selectivity of 48 experimental antimalarial drug targets was analyzed. Applying in silico gene deletions, 24 of these drug targets were found to be perfectly selective, in that they were essential for the parasite but non-essential for the human cell. The selectivity of a subset of enzymes, that were essential in both models, was evaluated with the reduced fitness concept. It was, then, possible to quantify the reduction in functional fitness of the two networks under the progressive inhibition of the same enzymatic activity. Overall, this in silico analysis provided a selectivity ranking that was in line with numerous in vivo and in vitro observations. Conclusions Genome-scale models can be useful to depict and quantify the effects of enzymatic inhibitions on the impaired production of biomass components. From the perspective of a host-pathogen metabolic interaction, an estimation of the drug targets-induced consequences can be beneficial for the development of a selective anti-parasitic drug.
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Affiliation(s)
- Susanna Bazzani
- Institut für Biochemie, Charite-Universitätsmedizin, Berlin, Germany.
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21
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Nosrati GR, Houk KN. Using catalytic atom maps to predict the catalytic functions present in enzyme active sites. Biochemistry 2012; 51:7321-9. [PMID: 22909276 DOI: 10.1021/bi3008438] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Catalytic atom maps (CAMs) are minimal models of enzyme active sites. The structures in the Protein Data Bank (PDB) were examined to determine if proteins with CAM-like geometries in their active sites all share the same catalytic function. We combined the CAM-based search protocol with a filter based on the weighted contact number (WCN) of the catalytic residues, a measure of the "crowdedness" of the microenvironment around a protein residue. Using this technique, a CAM based on the Ser-His-Asp catalytic triad of trypsin was able to correctly identify catalytic triads in other enzymes within 0.5 Å rmsd of the CAM with 96% accuracy. A CAM based on the Cys-Arg-(Asp/Glu) active site residues from the tyrosine phosphatase active site achieved 89% accuracy in identifying this type of catalytic functionality. Both of these CAMs were able to identify active sites across different fold types. Finally, the PDB was searched to locate proteins with catalytic functionality similar to that present in the active site of orotidine 5'-monophosphate decarboxylase (ODCase), whose mechanism is not known with certainty. A CAM, based on the conserved Lys-Asp-Lys-Asp tetrad in the ODCase active site, was used to search the PDB for enzymes with similar active sites. The ODCase active site has a geometry similar to that of Schiff base-forming Class I aldolases, with lowest aldolase rmsd to the ODCase CAM at 0.48 Å. The similarity between this CAM and the aldolase active site suggests that ODCase has the correct catalytic functionality present in its active site for the generation of a nucleophilic lysine.
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Affiliation(s)
- Geoffrey R Nosrati
- Department of Chemistry and Biochemistry, University of California, Los Angeles, California 90095-1569, United States
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22
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Tsang WY, Wood BM, Wong FM, Wu W, Gerlt JA, Amyes TL, Richard JP. 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 2012; 134:14580-94. [PMID: 22812629 DOI: 10.1021/ja3058474] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The exchange for deuterium of the C-6 protons of uridine 5'-monophosphate (UMP) and 5-fluorouridine 5'-monophosphate (F-UMP) catalyzed by yeast orotidine 5'-monophosphate decarboxylase (ScOMPDC) at pD 6.5-9.3 and 25 °C was monitored by (1)H NMR spectroscopy. Deuterium exchange proceeds by proton transfer from C-6 of the bound nucleotide to the deprotonated side chain of Lys-93 to give the enzyme-bound vinyl carbanion. The pD-rate profiles for k(cat) give turnover numbers for deuterium exchange into enzyme-bound UMP and F-UMP of 1.2 × 10(-5) and 0.041 s(-1), respectively, so that the 5-fluoro substituent results in a 3400-fold increase in the first-order rate constant for deuterium exchange. The binding of UMP and F-UMP to ScOMPDC results in 0.5 and 1.4 unit decreases, respectively, in the pK(a) of the side chain of the catalytic base Lys-93, showing that these nucleotides bind preferentially to the deprotonated enzyme. We also report the first carbon acid pK(a) values for proton transfer from C-6 of uridine (pK(CH) = 28.8) and 5-fluorouridine (pK(CH) = 25.1) in aqueous solution. The stabilizing effects of the 5-fluoro substituent on C-6 carbanion formation in solution (5 kcal/mol) and at ScOMPDC (6 kcal/mol) are similar. The binding of UMP and F-UMP to ScOMPDC results in a greater than 5 × 10(9)-fold increase in the equilibrium constant for proton transfer from C-6, so that ScOMPDC stabilizes the bound vinyl carbanions, relative to the bound nucleotides, by at least 13 kcal/mol. The pD-rate profile for k(cat)/K(m) for deuterium exchange into F-UMP gives the intrinsic second-order rate constant for exchange catalyzed by the deprotonated enzyme as 2300 M(-1) s(-1). This was used to calculate a total rate acceleration for ScOMPDC-catalyzed deuterium exchange of 3 × 10(10) M(-1), which corresponds to a transition-state stabilization for deuterium exchange of 14 kcal/mol. We conclude that a large portion of the total transition-state stabilization for the decarboxylation of orotidine 5'-monophosphate can be accounted for by stabilization of the enzyme-bound vinyl carbanion intermediate of the stepwise reaction.
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Affiliation(s)
- Wing-Yin Tsang
- Department of Chemistry, University at Buffalo, Buffalo, New York 14260, USA
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23
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5-azacytosine compounds in medicinal chemistry: current stage and future perspectives. Future Med Chem 2012; 4:991-1005. [DOI: 10.4155/fmc.12.36] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
This review summarizes the basic milestones of the research of 5-azacytosine nucleosides chronologically from their discovery and anticancer activity identification, through to subsequent unveiling of their mechanism of action based on DNA hypomethylation and tumor-suppressor gene reactivation, to the final US FDA approval of 5-azacytidine (Vidaza®) and 2´-deoxy-5-azacytidine (Dacogen®) for the treatment of myelodysplastic syndromes. 5,6-dihydro-2´-deoxy-5-azacytidine, a compound with anti-HIV activity through lethal mutagenesis, representing a unique mechanism of action among existing anti-retroviral drugs, is discussed together with quite recent discovery of its so far unexpected hypomethylation activity. Special attention is paid to 5-azacytosine acyclic nucleoside analogues and phosphonomethyl derivatives with the emphasis on the new potent anti-DNA virus agent (S)-1-[3-hydroxy-2-(phosphonomethoxy)propyl]-5-azacytosine and its prodrug forms. Considering the potential pharmaceutical applications, 5-azacytosine and 5,6-dihydro-5-azacytosine appear to be so far the most effective cytosine mimics for the design of novel antiviral and anti-tumor drug candidates.
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24
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Lin JB, He JL, Shih YC, Chien TC. Study on the synthesis of 6-alkylaminouridines via the nucleophilic aromatic substitution reaction of 6-cyanouridine derivatives. Tetrahedron Lett 2011. [DOI: 10.1016/j.tetlet.2011.05.033] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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25
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Lewis M, Meza-Avina ME, Wei L, Crandall IE, Bello AM, Poduch E, Liu Y, Paige CJ, Kain KC, Pai EF, Kotra LP. Novel interactions of fluorinated nucleotide derivatives targeting orotidine 5'-monophosphate decarboxylase. J Med Chem 2011; 54:2891-901. [PMID: 21417464 DOI: 10.1021/jm101642g] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
Abstract
Fluorinated nucleosides and nucleotides are of considerable interest to medicinal chemists because of their antiviral, anticancer, and other biological activities. However, their direct interactions at target binding sites are not well understood. A new class of 2'-deoxy-2'-fluoro-C6-substituted uridine and UMP derivatives were synthesized and evaluated as inhibitors of orotidine 5'-monophosphate decarboxylase (ODCase or OMPDCase). These compounds were synthesized from the key intermediate, fully protected 2'-deoxy-2'-fluorouridine. Among the synthesized compounds, 2'-deoxy-2'-fluoro-6-iodo-UMP covalently inhibited human ODCase with a second-order rate constant of 0.62 ± 0.02 M(-1) s(-1). Interestingly, the 6-cyano-2'-fluoro derivative covalently interacted with ODCase defying the conventional thinking, where its ribosyl derivative undergoes transformation into BMP by ODCase. This confirms that the 2'-fluoro moiety influences the chemistry at the C6 position of the nucleotides and thus interactions in the active site of ODCase. Molecular interactions of the 2'-fluorinated nucleotides are compared to those with the 3'-fluorinated nucleotides bound to the corresponding target enzyme, and the carbohydrate moieties were shown to bind in different conformations.
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Affiliation(s)
- Melissa Lewis
- Center for Molecular Design and Preformulations and Division of Cellular and Molecular Biology, Toronto General Research Institute, University Health Network, Toronto, Ontario, Canada
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26
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Burrows JN, Waterson D. Discovering New Medicines to Control and Eradicate Malaria. TOPICS IN MEDICINAL CHEMISTRY 2011. [DOI: 10.1007/7355_2011_14] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
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27
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Abdo M, Zhang Y, Schramm VL, Knapp S. Electrophilic aromatic selenylation: new OPRT inhibitors. Org Lett 2010; 12:2982-5. [PMID: 20521773 DOI: 10.1021/ol1010032] [Citation(s) in RCA: 56] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
2-Ethoxyethaneseleninic acid reacts with electron-rich aromatic substrates to deliver, by way of the selenoxides, the (2-ethoxyethyl)seleno ethers, which can in turn be transformed into a diverse set of aryl-selenylated products. Among these, a family of 5-uridinyl derivatives shows submicromolar inhibition of human and malarial orotate phosphoribosyltransferase.
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Affiliation(s)
- Mohannad Abdo
- Department of Chemistry & Chemical Biology, Rutgers, The State University of New Jersey, 610 Taylor Road, Piscataway, New Jersey 08854, USA
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28
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Huthmacher C, Hoppe A, Bulik S, Holzhütter HG. Antimalarial drug targets in Plasmodium falciparum predicted by stage-specific metabolic network analysis. BMC SYSTEMS BIOLOGY 2010; 4:120. [PMID: 20807400 PMCID: PMC2941759 DOI: 10.1186/1752-0509-4-120] [Citation(s) in RCA: 89] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/23/2009] [Accepted: 08/31/2010] [Indexed: 12/20/2022]
Abstract
BACKGROUND Despite enormous efforts to combat malaria the disease still afflicts up to half a billion people each year of which more than one million die. Currently no approved vaccine is available and resistances to antimalarials are widely spread. Hence, new antimalarial drugs are urgently needed. RESULTS Here, we present a computational analysis of the metabolism of Plasmodium falciparum, the deadliest malaria pathogen. We assembled a compartmentalized metabolic model and predicted life cycle stage specific metabolism with the help of a flux balance approach that integrates gene expression data. Predicted metabolite exchanges between parasite and host were found to be in good accordance with experimental findings when the parasite's metabolic network was embedded into that of its host (erythrocyte). Knock-out simulations identified 307 indispensable metabolic reactions within the parasite. 35 out of 57 experimentally demonstrated essential enzymes were recovered and another 16 enzymes, if additionally the assumption was made that nutrient uptake from the host cell is limited and all reactions catalyzed by the inhibited enzyme are blocked. This predicted set of putative drug targets, shown to be enriched with true targets by a factor of at least 2.75, was further analyzed with respect to homology to human enzymes, functional similarity to therapeutic targets in other organisms and their predicted potency for prophylaxis and disease treatment. CONCLUSIONS The results suggest that the set of essential enzymes predicted by our flux balance approach represents a promising starting point for further drug development.
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Affiliation(s)
- Carola Huthmacher
- Institute of Biochemistry, Charité, Monbijoustraße 2, 10117 Berlin, Germany
| | - Andreas Hoppe
- Institute of Biochemistry, Charité, Monbijoustraße 2, 10117 Berlin, Germany
| | - Sascha Bulik
- Institute of Biochemistry, Charité, Monbijoustraße 2, 10117 Berlin, Germany
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29
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Meza-Avina ME, Wei L, Liu Y, Poduch E, Bello AM, Mishra RK, Pai EF, Kotra LP. Structural determinants for the inhibitory ligands of orotidine-5'-monophosphate decarboxylase. Bioorg Med Chem 2010; 18:4032-41. [PMID: 20452222 DOI: 10.1016/j.bmc.2010.04.017] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2010] [Revised: 04/04/2010] [Accepted: 04/06/2010] [Indexed: 11/18/2022]
Abstract
In recent years, orotidine-5'-monophosphate decarboxylase (ODCase) has gained renewed attention as a drug target. As a part of continuing efforts to design novel inhibitors of ODCase, we undertook a comprehensive study of potent, structurally diverse ligands of ODCase and analyzed their structural interactions in the active site of ODCase. These ligands comprise of pyrazole or pyrimidine nucleotides including the mononucleotide derivatives of pyrazofurin, barbiturate ribonucleoside, and 5-cyanouridine, as well as, in a computational approach, 1,4-dihydropyridine-based non-nucleoside inhibitors such as nifedipine and nimodipine. All these ligands bind in the active site of ODCase exhibiting distinct interactions paving the way to design novel inhibitors against this interesting enzyme. We propose an empirical model for the ligand structure for rational modifications in new drug design and potentially new lead structures.
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30
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Sobkowski M. Chemistry and stereochemistry of internucleotide bond formation by the H-phosphonate method. NEW J CHEM 2010. [DOI: 10.1039/b9nj00679f] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
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31
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Prediction of potential antimalarial targets of artemisinin based on protein information from whole genome of Plasmodium falciparum. CHINESE SCIENCE BULLETIN-CHINESE 2009. [DOI: 10.1007/s11434-009-0634-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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32
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Heinrich D, Diederichsen U, Rudolph MG. Lys314 is a nucleophile in non-classical reactions of orotidine-5'-monophosphate decarboxylase. Chemistry 2009; 15:6619-25. [PMID: 19472232 DOI: 10.1002/chem.200900397] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
Orotidine-5'-monophosphate decarboxylase (OMPD) catalyzes the decarboxylation of orotidine-5'-monophosphate (OMP) to uridine-5'-monophosphate (UMP) in an extremely proficient manner. The reaction does not require any cofactors and proceeds by an unknown mechanism. In addition to decarboxylation, OMPD is able to catalyze other reactions. We show that several C6-substituted UMP derivatives undergo hydrolysis or substitution reactions that depend on a lysine residue (Lys314) in the OMPD active site. 6-Cyano-UMP is converted to UMP, and UMP derivatives with good leaving groups inhibit OMPD by a suicide mechanism in which Lys314 covalently binds to the substrate. These non-classical reactivities of human OMPD were characterized by cocrystallization and freeze-trapping experiments with wild-type OMPD and two active-site mutants by using substrate and inhibitor nucleotides. The structures show that the C6-substituents are not coplanar with the pyrimidine ring. The extent of this substrate distortion is a function of the substituent geometry. Structure-based mechanisms for the reaction of 6-substituted UMP derivatives are extracted in accordance with results from mutagenesis, mass spectrometry, and OMPD enzyme activity. The Lys314-based mechanisms explain the chemodiversity of OMPD, and offer a strategy to design mechanism-based inhibitors that could be used for antineoplastic purposes for example.
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Affiliation(s)
- Daniel Heinrich
- Institut für Organische und Biomolekulare Chemie, Georg-August-Universität Göttingen, Tammannstrasse 2, 37077 Göttingen, Germany
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33
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Bello AM, Konforte D, Poduch E, Furlonger C, Wei L, Liu Y, Lewis M, Pai EF, Paige CJ, Kotra LP. Structure-activity relationships of orotidine-5'-monophosphate decarboxylase inhibitors as anticancer agents. J Med Chem 2009; 52:1648-58. [PMID: 19260677 DOI: 10.1021/jm801224t] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
A series of 6-substituted and 5-fluoro-6-substituted uridine derivatives were synthesized and evaluated for their potential as anticancer agents. The designed molecules were synthesized from either fully protected uridine or the corresponding 5-fluorouridine derivatives. The mononucleotide derivatives were used for enzyme inhibition investigations against ODCase. Anticancer activities of all the synthesized derivatives were evaluated using the nucleoside forms of the inhibitors. 5-Fluoro-UMP was a very weak inhibitor of ODCase. 6-Azido-5-fluoro and 5-fluoro-6-iodo derivatives are covalent inhibitors of ODCase, and the active site Lys145 residue covalently binds to the ligand after the elimination of the 6-substitution. Among the synthesized nucleoside derivatives, 6-azido-5-fluoro, 6-amino-5-fluoro, and 6-carbaldehyde-5-fluoro derivatives showed potent anticancer activities in cell-based assays against various leukemia cell lines. On the basis of the overall profile, 6-azido-5-fluoro and 6-amino-5-fluoro uridine derivatives exhibited potential for further investigations.
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Affiliation(s)
- Angelica M Bello
- Center for Molecular Design and Preformulations and Division of Cellular and Molecular Biology, Toronto General Research Institute, Toronto General Hospital, Toronto, Ontario M5G 2C4, Canada
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34
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Fujihashi M, Bello AM, Kotra LP, Pai EF. Structural characterization of the molecular events during a slow substrate-product transition in orotidine 5'-monophosphate decarboxylase. J Mol Biol 2009; 387:1199-210. [PMID: 19236876 PMCID: PMC3125131 DOI: 10.1016/j.jmb.2009.02.037] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2008] [Revised: 02/05/2009] [Accepted: 02/06/2009] [Indexed: 01/07/2023]
Abstract
Crystal structures of substrate-product complexes of Methanobacterium thermoautotrophicum orotidine 5'-monophosphate decarboxylase, obtained at various steps in its catalysis of the unusual transformation of 6-cyano-uridine 5'-monophosphate (UMP) into barbituric acid ribosyl monophosphate, show that the cyano substituent of the substrate, when bound to the active site, is first bent significantly from the plane of the pyrimidine ring and then replaced by an oxygen atom. Although the K72A and D70A/K72A mutants are either catalytically impaired or even completely inactive, they still display bending of the C6 substituent. Interestingly, high-resolution structures of the D70A and D75N mutants revealed a covalent bond between C6 of UMP and the Lys72 side chain after the -CN moiety's release. The same covalent bond was observed when the native enzyme was incubated with 6-azido-UMP and 6-iodo-UMP; in contrast, the K72A mutant transformed 6-iodo-UMP to barbituric acid ribosyl 5'-monophosphate. These results demonstrate that, given a suitable environment, native orotidine 5'-monophosphate decarboxylase and several of its mutants are not restricted to the physiologically relevant decarboxylation; they are able to catalyze even nucleophilic substitution reactions but consistently maintain distortion on the C6 substituent as an important feature of catalysis.
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Affiliation(s)
- Masahiro Fujihashi
- Graduate School of Science, Kyoto University, Sakyo-ku, Kyoto, Japan 606-8502, Division of Cancer Genomics & Proteomics, Ontario Cancer Institute/Princess Margaret Hospital, MaRS Centre/Toronto Medical Discovery Tower, 101 College Street, Toronto, ON, M5G 1L7, Canada,Corresponding authors: and
| | - Angelica M. Bello
- Center for Molecular Design and Preformulations and Division of Cell and Molecular Biology, Toronto General Research Institute, MaRS Centre/Toronto Medical Discovery Tower, 101 College Street, Toronto, ON, M5G 1L7, Canada
| | - Lakshmi P. Kotra
- Center for Molecular Design and Preformulations and Division of Cell and Molecular Biology, Toronto General Research Institute, MaRS Centre/Toronto Medical Discovery Tower, 101 College Street, Toronto, ON, M5G 1L7, Canada, Departments of Pharmaceutical Sciences and Chemistry, University of Toronto, Toronto, Ontario, Canada, Department of Chemistry and Biochemistry, The University of North Carolina at Greensboro, Greensboro, NC 27402, USA
| | - Emil F. Pai
- Division of Cancer Genomics & Proteomics, Ontario Cancer Institute/Princess Margaret Hospital, MaRS Centre/Toronto Medical Discovery Tower, 101 College Street, Toronto, ON, M5G 1L7, Canada, Departments of Biochemistry, Medical Biophysics and Molecular Genetics, University of Toronto, Toronto, ON, M5S 1A8, Canada,Corresponding authors: and
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35
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Wong JH, Sahni U, Li Y, Chen X, Gervay-Hague J. Synthesis of sulfone-based nucleotide isosteres: identification of CMP-sialic acid synthetase inhibitors. Org Biomol Chem 2008; 7:27-9. [PMID: 19081938 DOI: 10.1039/b819155g] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
A modular replacement approach to the synthesis of sulfo-nucleotide analogs prepared from condensation of nucleoside aldehydes with bis phosphonate Horner-Wadsworth-Emmons reagents is disclosed. These analogs were shown to be inhibitors of Neisseria meningitidis CSS (NmCSS), which is a key enzyme in the biosynthesis of the capsular polysaccharides required for bacterial infection.
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Affiliation(s)
- Jessica H Wong
- Department of Chemistry, University of California, Davis, One Shields Avenue, Davis, CA, USA
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36
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Poduch E, Wei L, Pai EF, Kotra LP. Structural diversity and plasticity associated with nucleotides targeting orotidine monophosphate decarboxylase. J Med Chem 2008; 51:432-8. [PMID: 18181562 DOI: 10.1021/jm700968x] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Orotidine monophosphate decarboxylase (ODCase) generally accepts pyrimidine-based mononucleotides as ligands, but other nucleotides are also known to bind to this enzyme. We investigated the kinetic properties of eight common and endogenous nucleotides with ODCases from three species: Methanobacterium thermoautotrophicum, Plasmodium falciparum, and Homo sapiens. UMP and XMP exhibited higher affinities as compared to the other nucleotides tested. The product of ODCase catalyzed decarboxylation, UMP, displayed inhibition constants (K(i)) of 330 microM against the Mt enzyme and of 210 and 220 microM against the Pf and Hs ODCases, respectively. The K(i) values for XMP were 130 microM and 43 microM, respectively, for Mt and Pf ODCases. Interestingly, XMP's affinity for human ODCase (K(i) = 0.71 microM) is comparable and even slightly better than that of the substrate OMP. Binding of various nucleotides and their structural features in the context of ODCase inhibition and inhibitor design are discussed.
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Affiliation(s)
- Ewa Poduch
- Center for Molecular Design and Preformulations, Toronto General Research Institute, Toronto General Hospital, Toronto, ON, Canada
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