1
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Examination of multiple Trypanosoma cruzi targets in a new drug discovery approach for Chagas disease. Bioorg Med Chem 2022; 58:116577. [DOI: 10.1016/j.bmc.2021.116577] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2021] [Revised: 12/10/2021] [Accepted: 12/10/2021] [Indexed: 12/21/2022]
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2
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Madhav H, Hoda N. An insight into the recent development of the clinical candidates for the treatment of malaria and their target proteins. Eur J Med Chem 2020; 210:112955. [PMID: 33131885 DOI: 10.1016/j.ejmech.2020.112955] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2020] [Revised: 10/08/2020] [Accepted: 10/19/2020] [Indexed: 01/18/2023]
Abstract
Malaria is an endemic disease, prevalent in tropical and subtropical regions which cost half of million deaths annually. The eradication of malaria is one of the global health priority nevertheless, current therapeutic efforts seem to be insufficient due to the emergence of drug resistance towards most of the available drugs, even first-line treatment ACT, unavailability of the vaccine, and lack of drugs with a new mechanism of action. Intensification of antimalarial research in recent years has resulted into the development of single dose multistage therapeutic agents which has advantage of overcoming the antimalarial drug resistance. The present review explored the current progress in the development of new promising antimalarials against prominent target proteins that have the potential to be a clinical candidate. Here, we also reviewed different aspects of drug resistance and highlighted new drug candidates that are currently in a clinical trial or clinical development, along with a few other molecules with excellent antimalarial activity overs ACTs. The summarized scientific value of previous approaches and structural features of antimalarials related to the activity are highlighted that will be helpful for the development of next-generation antimalarials.
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Affiliation(s)
- Hari Madhav
- Drug Design and Synthesis Laboratory, Department of Chemistry, Jamia Millia Islamia (A Central University), New Delhi, 110025, India.
| | - Nasimul Hoda
- Drug Design and Synthesis Laboratory, Department of Chemistry, Jamia Millia Islamia (A Central University), New Delhi, 110025, India.
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3
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Eck T, Patel S, Candela T, Leon H K, Little M, Reis NE, Liyanagunawardana U, Gubler U, Janson CA, Catalano J, Goodey NM. Mutational analysis confirms the presence of distal inhibitor-selectivity determining residues in B. stearothermophilus dihydrofolate reductase. Arch Biochem Biophys 2020; 692:108545. [PMID: 32810476 PMCID: PMC10727455 DOI: 10.1016/j.abb.2020.108545] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2020] [Revised: 08/08/2020] [Accepted: 08/12/2020] [Indexed: 11/20/2022]
Abstract
Many antibacterial and antiparasitic drugs work by competitively inhibiting dihydrofolate reductase (DHFR), a vital enzyme in folate metabolism. The interactions between inhibitors and DHFR active site residues are known in many homologs but the contributions from distal residues are less understood. Identifying distal residues that aid in inhibitor binding can improve targeted drug development programs by accounting for distant influences that may be less conserved and subject to frequent resistance causing mutations. Previously, a novel, homology-based, computational approach that mines ligand inhibition data was used to predict residues involved in inhibitor selectivity in the DHFR family. Expectedly, some inhibitor selectivity determining residue positions were predicted to lie in the active site and coincide with experimentally known inhibitor selectivity determining positions. However, other residues that group spatially in clusters distal to the active site have not been previously investigated. In this study, the effect of introducing amino acid substitutions at one of these predicted clusters (His38-Ala39-Ile40) on the inhibitor selectivity profile in Bacillus stearothermophilus dihydrofolate reductase (Bs DHFR) was investigated. Mutations were introduced into these cluster positions to change sidechain chemistry and size. We determined kcat and KM values and measured KD values at equilibrium for two competitive DHFR inhibitors, trimethoprim (TMP) and pyrimethamine (PYR). Mutations in the His38-Ala39-Ile40 cluster significantly impacted inhibitor binding and TMP/PYR selectivity - seven out of nine mutations resulted in tighter binding to PYR when compared to TMP. These data suggest that the His38-Ala39-Ile40 cluster is a distal inhibitor selectivity determining region that favors PYR binding in Bs DHFR and, possibly, throughout the DHFR family.
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Affiliation(s)
- Tyler Eck
- Dept. of Chemistry & Biochemistry, Montclair State University, Montclair, NJ, 07043, USA
| | - Seema Patel
- Dept. of Chemistry & Biochemistry, Montclair State University, Montclair, NJ, 07043, USA
| | - Thomas Candela
- Dept. of Chemistry & Biochemistry, Montclair State University, Montclair, NJ, 07043, USA
| | - Katherine Leon H
- Dept. of Chemistry & Biochemistry, Montclair State University, Montclair, NJ, 07043, USA
| | - Michael Little
- Dept. of Chemistry & Biochemistry, Montclair State University, Montclair, NJ, 07043, USA
| | - Natalia E Reis
- Dept. of Chemistry & Biochemistry, Montclair State University, Montclair, NJ, 07043, USA
| | | | - Ueli Gubler
- Dept. of Chemistry & Biochemistry, Montclair State University, Montclair, NJ, 07043, USA
| | - Cheryl A Janson
- Dept. of Chemistry & Biochemistry, Montclair State University, Montclair, NJ, 07043, USA
| | - Jaclyn Catalano
- Dept. of Chemistry & Biochemistry, Montclair State University, Montclair, NJ, 07043, USA
| | - Nina M Goodey
- Dept. of Chemistry & Biochemistry, Montclair State University, Montclair, NJ, 07043, USA.
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4
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Sharma VK, Bharatam PV. Identification of Selective Inhibitors of LdDHFR Enzyme Using Pharmacoinformatic Methods. J Comput Biol 2020; 28:43-59. [PMID: 32207987 DOI: 10.1089/cmb.2019.0332] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
Dihydrofolate reductase (DHFR) is a well-known enzyme of the folate metabolic pathway and it is a validated drug target for leishmaniasis. However, only a few leads are reported against Leishmania donovani DHFR (LdDHFR), and thus, there is a need to identify new inhibitors. In this article, pharmacoinformatic tools such as molecular docking, virtual screening, absorption, distribution, metabolism, excretion, and toxicity (ADMET) profiling, and molecular dynamics (MD) simulations were utilized to identify potential LdDHFR inhibitors. Initially, a natural DHFR substrate (dihydrofolate), a classical DHFR inhibitor (methotrexate), and a potent LdDHFR inhibitor, that is, "5-(3-(octyloxy)benzyl)pyrimidine-2,4-diamine" (LEAD) were docked in the active site of the LdDHFR and MD simulated to understand the binding mode characteristics of the substrates/inhibitors in the LdDHFR. The shape of the LEAD molecule was used as a query for shape-based virtual screening, while the three-dimensional structure of LdDHFR was utilized for docking-based virtual screening. In silico ADMET factors were also considered during virtual screening. These two screening processes yielded 25 suitable hits, which were further validated for their selectivity toward LdDHFR using molecular docking and prime molecular mechanics/generalized born surface area analysis in the human DHFR (HsDHFR). Best six hits, which were selective and energetically favorable for the LdDHFR, were chosen for MD simulations. The MD analysis showed that four of the hits exhibited very good binding affinity for LdDHFR with respect to HsDHFR, and two hits were found to be more selective than the reported potent LdDHFR inhibitor. The present study thus identifies hits that can be further designed and modified as potent LdDHFR inhibitors.
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Affiliation(s)
- Vishnu Kumar Sharma
- Department of Pharmacoinformatics and National Institute of Pharmaceutical Education and Research (NIPER), S.A.S. Nagar, India
| | - Prasad V Bharatam
- Department of Medicinal Chemistry, National Institute of Pharmaceutical Education and Research (NIPER), S.A.S. Nagar, India
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5
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Ragab FA, Nissan YM, Seif EM, Maher A, Arafa RK. Synthesis and in vitro investigation of novel cytotoxic pyrimidine and pyrazolopyrimidne derivatives showing apoptotic effect. Bioorg Chem 2020; 96:103621. [DOI: 10.1016/j.bioorg.2020.103621] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2019] [Revised: 01/01/2020] [Accepted: 01/22/2020] [Indexed: 12/17/2022]
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6
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Design, synthesis and anti-tumour activity of new pyrimidine-pyrrole appended triazoles. Toxicol In Vitro 2019; 60:87-96. [DOI: 10.1016/j.tiv.2019.05.009] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2019] [Revised: 04/18/2019] [Accepted: 05/13/2019] [Indexed: 12/17/2022]
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7
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Pomel S, Mao W, Ha-Duong T, Cavé C, Loiseau PM. GDP-Mannose Pyrophosphorylase: A Biologically Validated Target for Drug Development Against Leishmaniasis. Front Cell Infect Microbiol 2019; 9:186. [PMID: 31214516 PMCID: PMC6554559 DOI: 10.3389/fcimb.2019.00186] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2019] [Accepted: 05/15/2019] [Indexed: 01/02/2023] Open
Abstract
Leishmaniases are neglected tropical diseases that threaten about 350 million people in 98 countries around the world. In order to find new antileishmanial drugs, an original approach consists in reducing the pathogenic effect of the parasite by impairing the glycoconjugate biosynthesis, necessary for parasite recognition and internalization by the macrophage. Some proteins appear to be critical in this way, and one of them, the GDP-Mannose Pyrophosphorylase (GDP-MP), is an attractive target for the design of specific inhibitors as it is essential for Leishmania survival and it presents significant differences with the host counterpart. Two GDP-MP inhibitors, compounds A and B, have been identified in two distinct studies by high throughput screening and by a rational approach based on molecular modeling, respectively. Compound B was found to be the most promising as it exhibited specific competitive inhibition of leishmanial GDP-MP and antileishmanial activities at the micromolar range with interesting selectivity indexes, as opposed to compound A. Therefore, compound B can be used as a pharmacological tool for the development of new specific antileishmanial drugs.
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Affiliation(s)
- Sébastien Pomel
- UMR 8076 CNRS BioCIS, Université Paris-Sud, Université Paris-Saclay, Châtenay-Malabry, France
| | - Wei Mao
- UMR 8076 CNRS BioCIS, Université Paris-Sud, Université Paris-Saclay, Châtenay-Malabry, France
| | - Tâp Ha-Duong
- UMR 8076 CNRS BioCIS, Université Paris-Sud, Université Paris-Saclay, Châtenay-Malabry, France
| | - Christian Cavé
- UMR 8076 CNRS BioCIS, Université Paris-Sud, Université Paris-Saclay, Châtenay-Malabry, France
| | - Philippe M Loiseau
- UMR 8076 CNRS BioCIS, Université Paris-Sud, Université Paris-Saclay, Châtenay-Malabry, France
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8
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Webster LA, Thomas M, Urbaniak M, Wyllie S, Ong H, Tinti M, Fairlamb AH, Boesche M, Ghidelli-Disse S, Drewes G, Gilbert IH. Development of Chemical Proteomics for the Folateome and Analysis of the Kinetoplastid Folateome. ACS Infect Dis 2018; 4:1475-1486. [PMID: 30264983 PMCID: PMC6199744 DOI: 10.1021/acsinfecdis.8b00097] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
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The folate pathway has been extensively
studied in a number of organisms, with its essentiality exploited
by a number of drugs. However, there has been little success in developing
drugs that target folate metabolism in the kinetoplastids. Despite
compounds being identified which show significant inhibition of the
parasite enzymes, this activity does not translate well into cellular
and animal models of disease. Understanding to which enzymes antifolates
bind under physiological conditions and how this corresponds to the
phenotypic response could provide insight on how to target the folate
pathway in these organisms. To facilitate this, we have adopted a
chemical proteomics approach to study binding of compounds to enzymes
of folate metabolism. Clinical and literature antifolate compounds
were immobilized onto resins to allow for “pull down”
of the proteins in the “folateome”. Using competition
studies, proteins, which bind the beads specifically and nonspecifically,
were identified in parasite lysate (Trypanosoma brucei and Leishmania major) for each antifolate compound.
Proteins were identified through tryptic digest, tandem mass tag (TMT)
labeling of peptides followed by LC-MS/MS. This approach was further
exploited by creating a combined folate resin (folate beads). The
resin could pull down up to 9 proteins from the folateome. This information
could be exploited in gaining a better understanding of folate metabolism
in kinetoplastids and other organisms.
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Affiliation(s)
- Lauren A. Webster
- Division of Biological Chemistry and Drug Discovery, College of Life Sciences, University of Dundee, Dundee, DD1 5EH, United Kingdom
| | - Michael Thomas
- Division of Biological Chemistry and Drug Discovery, College of Life Sciences, University of Dundee, Dundee, DD1 5EH, United Kingdom
| | - Michael Urbaniak
- Division of Biological Chemistry and Drug Discovery, College of Life Sciences, University of Dundee, Dundee, DD1 5EH, United Kingdom
| | - Susan Wyllie
- Division of Biological Chemistry and Drug Discovery, College of Life Sciences, University of Dundee, Dundee, DD1 5EH, United Kingdom
| | - Han Ong
- Division of Biological Chemistry and Drug Discovery, College of Life Sciences, University of Dundee, Dundee, DD1 5EH, United Kingdom
| | - Michele Tinti
- Division of Biological Chemistry and Drug Discovery, College of Life Sciences, University of Dundee, Dundee, DD1 5EH, United Kingdom
| | - Alan H. Fairlamb
- Division of Biological Chemistry and Drug Discovery, College of Life Sciences, University of Dundee, Dundee, DD1 5EH, United Kingdom
| | - Markus Boesche
- Cellzome - a GSK company, Meyerhofstrasse 1, Heidelberg, 69117, Germany
| | | | - Gerard Drewes
- Cellzome - a GSK company, Meyerhofstrasse 1, Heidelberg, 69117, Germany
| | - Ian H. Gilbert
- Division of Biological Chemistry and Drug Discovery, College of Life Sciences, University of Dundee, Dundee, DD1 5EH, United Kingdom
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9
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Cullia G, Tamborini L, Conti P, De Micheli C, Pinto A. Folates in Trypanosoma brucei
: Achievements and Opportunities. ChemMedChem 2018; 13:2150-2158. [DOI: 10.1002/cmdc.201800500] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2018] [Indexed: 12/11/2022]
Affiliation(s)
- Gregorio Cullia
- Institute of Biomolecules Max Mousseron (IBMM); UMR5247; CNRS; University of Montpellier; ENSCM; Place Eugène Battaillon 34095 Montpellier cedex 5 France
| | - Lucia Tamborini
- Department of Pharmaceutical Sciences (DISFARM); University of Milan; via Luigi Mangiagalli 25 20133 Milano Italy
| | - Paola Conti
- Department of Pharmaceutical Sciences (DISFARM); University of Milan; via Luigi Mangiagalli 25 20133 Milano Italy
| | - Carlo De Micheli
- Department of Pharmaceutical Sciences (DISFARM); University of Milan; via Luigi Mangiagalli 25 20133 Milano Italy
| | - Andrea Pinto
- Department of Food Environmental and Nutritional Sciences; University of Milan; via Giovanni Celoria 2 20133 Milano Italy
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10
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Synthesis and bioactivity evaluation of new pyrimidinone-5-carbonitriles as potential anticancer and antimicrobial agents. RESEARCH ON CHEMICAL INTERMEDIATES 2018. [DOI: 10.1007/s11164-018-3254-y] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
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11
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Sharma VK, Abbat S, Bharatam PV. Pharmacoinformatic Study on the Selective Inhibition of the Protozoan Dihydrofolate Reductase Enzymes. Mol Inform 2017; 36. [PMID: 28605138 DOI: 10.1002/minf.201600156] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/24/2016] [Accepted: 05/16/2017] [Indexed: 12/27/2022]
Abstract
Dihydrofolate reductase (DHFR) is an essential enzyme of the folate metabolic pathway in protozoa and it is a validated, potential drug target in many infectious diseases. Information about unique conserved residues of the DHFR enzyme is required to understand residual selectivity of the protozoan DHFR enzyme. The three dimensional crystal structures are not available for all the protozoan DHFR enzymes. Enzyme-substrate/inhibitor interaction information is required for the binding mode characterization in protozoan DHFR for selective inhibitor design. In this work, multiple sequence analysis was carried out in all the studied species. Homology models were built for protozoan DHFR enzymes, for which 3D structures are not available in PDB. The molecular docking and Prime-MMGBSA calculations of the natural substrate (dihydrofolate, DHF) and classical DHFR inhibitor (methotrexate, MTX) were performed in protozoan DHFR enzymes. Comparative sequence analysis showed that an overall sequence identity between the studied species ranging from 22.94 % (CfDHFR-BgDHFR) to 94.61 % (LdDHFR-LmDHFR). Interestingly, it was observed that most of the active site residues were conserved in all the cases and all the enzymes exhibit similar key binding interactions with DHF and MTX in molecular docking analysis, but there are a few key binding residues which differ in protozoan species that makes it suitable for target selectivity. This information can be used to design selective and potent protozoan DHFR enzyme inhibitors.
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Affiliation(s)
- Vishnu K Sharma
- Department of Pharmacoinformatics, National Institute of Pharmaceutical Education and Research (NIPER), S.A.S Nagar-, 160 062, Punjab, India
| | - Sheenu Abbat
- Department of Pharmacoinformatics, National Institute of Pharmaceutical Education and Research (NIPER), S.A.S Nagar-, 160 062, Punjab, India
| | - P V Bharatam
- Department of Medicinal Chemistry, National Institute of Pharmaceutical Education and Research (NIPER), S.A.S Nagar-160 062, Punjab, India
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12
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Nyíri K, Vértessy BG. Perturbation of genome integrity to fight pathogenic microorganisms. Biochim Biophys Acta Gen Subj 2016; 1861:3593-3612. [PMID: 27217086 DOI: 10.1016/j.bbagen.2016.05.024] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2016] [Revised: 05/05/2016] [Accepted: 05/18/2016] [Indexed: 10/21/2022]
Abstract
BACKGROUND Resistance against antibiotics is unfortunately still a major biomedical challenge for a wide range of pathogens responsible for potentially fatal diseases. SCOPE OF REVIEW In this study, we aim at providing a critical assessment of the recent advances in design and use of drugs targeting genome integrity by perturbation of thymidylate biosynthesis. MAJOR CONCLUSION We find that research efforts from several independent laboratories resulted in chemically highly distinct classes of inhibitors of key enzymes within the routes of thymidylate biosynthesis. The present article covers numerous studies describing perturbation of this metabolic pathway in some of the most challenging pathogens like Mycobacterium tuberculosis, Plasmodium falciparum, and Staphylococcus aureus. GENERAL SIGNIFICANCE Our comparative analysis allows a thorough summary of the current approaches to target thymidylate biosynthesis enzymes and also include an outlook suggesting novel ways of inhibitory strategies. This article is part of a Special Issue entitled "Science for Life" Guest Editor: Dr. Austen Angell, Dr. Salvatore Magazù and Dr. Federica Migliardo.
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Affiliation(s)
- Kinga Nyíri
- Dept. Biotechnology, Budapest University of Technology and Economics, 4 Szent Gellért tér, Budapest HU 1111, Hungary; Institute of Enzymology, RCNS, Hungarian Academy of Sciences, 2 Magyar tudósok körútja, Budapest HU 1117, Hungary.
| | - Beáta G Vértessy
- Dept. Biotechnology, Budapest University of Technology and Economics, 4 Szent Gellért tér, Budapest HU 1111, Hungary; Institute of Enzymology, RCNS, Hungarian Academy of Sciences, 2 Magyar tudósok körútja, Budapest HU 1117, Hungary.
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13
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Gibson MW, Dewar S, Ong HB, Sienkiewicz N, Fairlamb AH. Trypanosoma brucei DHFR-TS Revisited: Characterisation of a Bifunctional and Highly Unstable Recombinant Dihydrofolate Reductase-Thymidylate Synthase. PLoS Negl Trop Dis 2016; 10:e0004714. [PMID: 27175479 PMCID: PMC4866688 DOI: 10.1371/journal.pntd.0004714] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2016] [Accepted: 04/25/2016] [Indexed: 11/19/2022] Open
Abstract
Bifunctional dihydrofolate reductase-thymidylate synthase (DHFR-TS) is a chemically and genetically validated target in African trypanosomes, causative agents of sleeping sickness in humans and nagana in cattle. Here we report the kinetic properties and sensitivity of recombinant enzyme to a range of lipophilic and classical antifolate drugs. The purified recombinant enzyme, expressed as a fusion protein with elongation factor Ts (Tsf) in ThyA- Escherichia coli, retains DHFR activity, but lacks any TS activity. TS activity was found to be extremely unstable (half-life of 28 s) following desalting of clarified bacterial lysates to remove small molecules. Stability could be improved 700-fold by inclusion of dUMP, but not by other pyrimidine or purine (deoxy)-nucleosides or nucleotides. Inclusion of dUMP during purification proved insufficient to prevent inactivation during the purification procedure. Methotrexate and trimetrexate were the most potent inhibitors of DHFR (Ki 0.1 and 0.6 nM, respectively) and FdUMP and nolatrexed of TS (Ki 14 and 39 nM, respectively). All inhibitors showed a marked drop-off in potency of 100- to 1,000-fold against trypanosomes grown in low folate medium lacking thymidine. The most potent inhibitors possessed a terminal glutamate moiety suggesting that transport or subsequent retention by polyglutamylation was important for biological activity. Supplementation of culture medium with folate markedly antagonised the potency of these folate-like inhibitors, as did thymidine in the case of the TS inhibitors raltitrexed and pemetrexed.
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Affiliation(s)
- Marc W. Gibson
- Division of Biological Chemistry and Drug Discovery, School of Life Sciences, University of Dundee, Dundee, United Kingdom
| | - Simon Dewar
- Division of Biological Chemistry and Drug Discovery, School of Life Sciences, University of Dundee, Dundee, United Kingdom
| | - Han B. Ong
- Division of Biological Chemistry and Drug Discovery, School of Life Sciences, University of Dundee, Dundee, United Kingdom
| | - Natasha Sienkiewicz
- Division of Biological Chemistry and Drug Discovery, School of Life Sciences, University of Dundee, Dundee, United Kingdom
| | - Alan H. Fairlamb
- Division of Biological Chemistry and Drug Discovery, School of Life Sciences, University of Dundee, Dundee, United Kingdom
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14
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Bhosle A, Chandra N. Structural analysis of dihydrofolate reductases enables rationalization of antifolate binding affinities and suggests repurposing possibilities. FEBS J 2016; 283:1139-67. [PMID: 26797763 DOI: 10.1111/febs.13662] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2015] [Revised: 12/03/2015] [Accepted: 01/14/2016] [Indexed: 11/28/2022]
Abstract
Antifolates are competitive inhibitors of dihydrofolate reductase (DHFR), a conserved enzyme that is central to metabolism and widely targeted in pathogenic diseases, cancer and autoimmune disorders. Although most clinically used antifolates are known to be target specific, some display a fair degree of cross-reactivity with DHFRs from other species. A method that enables identification of determinants of affinity and specificity in target DHFRs from different species and provides guidelines for the design of antifolates is currently lacking. To address this, we first captured the potential druggable space of a DHFR in a substructure called the 'supersite' and classified supersites of DHFRs from 56 species into 16 'site-types' based on pairwise structural similarity. Analysis of supersites across these site-types revealed that DHFRs exhibit varying extents of dissimilarity at structurally equivalent positions in and around the binding site. We were able to explain the pattern of affinities towards chemically diverse antifolates exhibited by DHFRs of different site-types based on these structural differences. We then generated an antifolate-DHFR network by mapping known high-affinity antifolates to their respective supersites and used this to identify antifolates that can be repurposed based on similarity between supersites or antifolates. Thus, we identified 177 human-specific and 458 pathogen-specific antifolates, a large number of which are supported by available experimental data. Thus, in the light of the clinical importance of DHFR, we present a novel approach to identifying differences in the druggable space of DHFRs that can be utilized for rational design of antifolates.
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Affiliation(s)
- Amrisha Bhosle
- Department of Biochemistry, Indian Institute of Science, Bangalore, India
| | - Nagasuma Chandra
- Department of Biochemistry, Indian Institute of Science, Bangalore, India
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15
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Singla P, Luxami V, Paul K. Triazine as a promising scaffold for its versatile biological behavior. Eur J Med Chem 2015; 102:39-57. [PMID: 26241876 DOI: 10.1016/j.ejmech.2015.07.037] [Citation(s) in RCA: 59] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2015] [Revised: 07/19/2015] [Accepted: 07/20/2015] [Indexed: 12/19/2022]
Abstract
Among all heterocycles, the triazine scaffold occupies a prominent position, possessing a broad range of biological activities. Triazine is found in many potent biologically active molecules with promising biological potential like anti-inflammatory, anti-mycobacterial, anti-viral, anti-cancer etc. which makes it an attractive scaffold for the design and development of new drugs. The wide spectrum of biological activity of this moiety has attracted attention in the field of medicinal chemistry. Due to these biological activities, their structure-activity relationship has generated interest among medicinal chemists and this has culminated in the discovery of several lead molecules. The outstanding development of triazine derivatives in diverse diseases within very short span of time proves its magnitude for medicinal chemistry research. Therefore, these compounds have been synthesized as target structure by many researchers, and were further evaluated for their biological activities. In this review, we have compiled and discussed the biological potential of s-triazine derivatives, which could provide a low-height flying bird's eye view of the triazine derived compounds to a medicinal chemist, for a comprehensive and target oriented information for the development of clinically viable drugs.
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Affiliation(s)
- Prinka Singla
- School of Chemistry and Biochemistry, Thapar University, Patiala 147004, India
| | - Vijay Luxami
- School of Chemistry and Biochemistry, Thapar University, Patiala 147004, India
| | - Kamaldeep Paul
- School of Chemistry and Biochemistry, Thapar University, Patiala 147004, India.
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16
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Sharma V, Chitranshi N, Agarwal AK. Significance and biological importance of pyrimidine in the microbial world. INTERNATIONAL JOURNAL OF MEDICINAL CHEMISTRY 2014; 2014:202784. [PMID: 25383216 PMCID: PMC4207407 DOI: 10.1155/2014/202784] [Citation(s) in RCA: 78] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/01/2013] [Revised: 01/13/2014] [Accepted: 01/14/2014] [Indexed: 11/20/2022]
Abstract
Microbes are unique creatures that adapt to varying lifestyles and environment resistance in extreme or adverse conditions. The genetic architecture of microbe may bear a significant signature not only in the sequences position, but also in the lifestyle to which it is adapted. It becomes a challenge for the society to find new chemical entities which can treat microbial infections. The present review aims to focus on account of important chemical moiety, that is, pyrimidine and its various derivatives as antimicrobial agents. In the current studies we represent more than 200 pyrimidines as antimicrobial agents with different mono-, di-, tri-, and tetrasubstituted classes along with in vitro antimicrobial activities of pyrimidines derivatives which can facilitate the development of more potent and effective antimicrobial agents.
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Affiliation(s)
- Vinita Sharma
- School of Pharmacy, Lloyd Institute of Management & Technology, Plot. No. 11, Knowledge Park II, Greater Noida, Uttar Pradesh 201306, India
| | - Nitin Chitranshi
- Bioinformatics Centre, Biotech Park, Sector G, Jankipuram, Lucknow, Uttar Pradesh 226021, India
- Gautam Buddh Technical University, IET Campus, Sitapur Road, Lucknow, Uttar Pradesh 226021, India
| | - Ajay Kumar Agarwal
- Department of Pharmaceutical Sciences, University Institute of Pharmaceutical Sciences, Kurukshetra University, Kurukshetra, Haryana 136119, India
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17
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Then RL. Antimicrobial Dihydrofolate Reductase Inhibitors - Achievements and Future Options: Review. J Chemother 2013; 16:3-12. [PMID: 15077993 DOI: 10.1179/joc.2004.16.1.3] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/31/2022]
Abstract
Despite all progress made in the fight against infections caused by bacteria, fungi, protozoa or viruses, there is a need for more and new active agents. Intensive efforts are currently directed against many new and attractive targets, and are hoped to result in new useful agents. The opportunities offered by some known and validated targets are, however, by far not exhausted. Dihydrofolate reductase (DHFR, EC 1.5.1.3) attracted much attention over several decades, which yielded several useful agents. There are excellent chances for new drugs in this field, and they are thought to increase by limiting the spectrum of activity. Whereas trimethoprim seems to present the optimum which can be achieved for a broad spectrum antibacterial agent, specific agents could probably be designed for well defined groups or specific organisms, such as staphylococci among the bacteria, or for a number of parasites, such as Plasmodium falciparum, the fungus Pneumocystis carinii, and several protozoa, such as Trypanosoma, Toxoplasma, and others. This would even extend to herbicides or specific plant pathogens. Achievements and current efforts directed against new DHFR-inhibitors are reviewed, considering only the most recent literature.
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Affiliation(s)
- R L Then
- Morphochem AG, Microbiology, CH-4058 Basel, Switzerland.
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Synthesis and biological evaluation of a novel series of aryl S,N-ketene acetals as antileishmanial agents. Bioorg Med Chem Lett 2013; 23:3979-82. [DOI: 10.1016/j.bmcl.2013.04.025] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2012] [Revised: 04/05/2013] [Accepted: 04/09/2013] [Indexed: 11/24/2022]
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Synthesis, biological evaluation and molecular docking studies of some pyrimidine derivatives. Eur J Med Chem 2013; 66:276-95. [PMID: 23811090 DOI: 10.1016/j.ejmech.2013.05.028] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2013] [Revised: 04/28/2013] [Accepted: 05/22/2013] [Indexed: 11/20/2022]
Abstract
Some novel pyrimidine-5-carbonitrile derivatives bearing various substituent have been synthesized. The structures of target compounds were confirmed by elemental analysis and spectral data. Some selected members of the newly synthesized compounds were investigated for their cytotoxic potency against certain human tumor cell lines. Five representative active anticancer compounds 6a, 6c, 6d, 17a and 18a were subjected to docking using MOE program on the 3D structure of two enzymes, namely; thymidylate synthase and dihydrofolate reductase. The antimicrobial activities of the synthesized compounds were tested against Staphylococcus aureus, Pseudomonas aeruginosa, Shigella flexneri and Candida albicans. Compounds 2c, 7a and 9c showed broad spectrum antimicrobial activity.
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20
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Tiwari A, Kumar S, Suryawanshi S, Mittal M, Vishwakarma P, Gupta S. Chemotherapy of leishmaniasis part X: Synthesis and bioevaluation of novel terpenyl heterocycles. Bioorg Med Chem Lett 2013. [DOI: 10.1016/j.bmcl.2012.10.110] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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21
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Kumar S, Tiwari A, Suryawanshi SN, Mittal M, Vishwakarma P, Gupta S. Chemotherapy of leishmaniasis. Part IX: synthesis and bioevaluation of aryl substituted ketene dithioacetals as antileishmanial agents. Bioorg Med Chem Lett 2012; 22:6728-30. [PMID: 23031588 DOI: 10.1016/j.bmcl.2012.08.096] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2012] [Revised: 08/21/2012] [Accepted: 08/24/2012] [Indexed: 10/27/2022]
Abstract
A new series of aryl substituted ketene dithioacetals 6a-h was synthesized and evaluated for their in vitro and in vivo antileishmanial activity against Leishmania donovani. Two compounds exhibited significant in vitro activity against intracellular amastigotes of L. donovani with IC(50) values 3.56 and 5.12 μM and were found promising as compared with reference drug, miltefosine. On the basis of good Selectivity Indices (S.I.), they were further tested for their in vivo response against L. donovani/hamster model and showed significant inhibition of parasite multiplication 78% and 83%, respectively. These compounds were better than the existing antileishmanials in respect to IC(50) and SI values, but were less active than miltefosine in vivo.
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Affiliation(s)
- Santosh Kumar
- Division of Medicinal Chemistry, Central Drug Research Institute, CSIR, Lucknow 226001, India
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22
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Chemoenzymatic synthesis and biological evaluation of 2- and 3-hydroxypyridine derivatives against Leishmania mexicana. Bioorg Med Chem 2012; 20:4614-24. [DOI: 10.1016/j.bmc.2012.06.028] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2012] [Revised: 06/08/2012] [Accepted: 06/15/2012] [Indexed: 01/01/2023]
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23
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Dihydrofolate reductase as a therapeutic target for infectious diseases: opportunities and challenges. Future Med Chem 2012; 4:1335-65. [DOI: 10.4155/fmc.12.68] [Citation(s) in RCA: 48] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022] Open
Abstract
Infectious diseases caused by parasites continue to take a massive toll on human health in the poor regions of the world. Filling the anti-infective drug-discovery pipeline has never been as challenging as it is now. The organisms responsible for these diseases have interesting biology with many potential biochemical targets. Inhibition of metabolic enzymes has been established as an attractive strategy for anti-infectious drug development. In this field, dihydrofolate reductase (DHFR) is an important enzyme in nucleic and amino acid synthesis and an extensively studied drug target over the past 50 years. The challenges for novel DHFR inhibition-based chemotherapeutics for the treatment of infectious diseases are now focused on overcoming the resistance problem as well as cost–effectiveness. Each year, the large number of literature citations attest the continued popularity of DHFR. It becomes truly the ‘enzyme of choice for all seasons and almost all reasons’. Herein, we summarize the opportunities and challenges in developing novel lead based on this target.
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Prediction of residues involved in inhibitor specificity in the dihydrofolate reductase family. BIOCHIMICA ET BIOPHYSICA ACTA-PROTEINS AND PROTEOMICS 2011; 1814:1870-9. [DOI: 10.1016/j.bbapap.2011.08.001] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/25/2011] [Revised: 07/29/2011] [Accepted: 08/01/2011] [Indexed: 12/11/2022]
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25
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Vanichtanankul J, Taweechai S, Yuvaniyama J, Vilaivan T, Chitnumsub P, Kamchonwongpaisan S, Yuthavong Y. Trypanosomal dihydrofolate reductase reveals natural antifolate resistance. ACS Chem Biol 2011; 6:905-11. [PMID: 21650210 DOI: 10.1021/cb200124r] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Dihydrofolate reductase (DHFR) is a potential drug target for Trypanosoma brucei, a human parasite, which is the causative agent for African sleeping sickness. No drug is available against this target, since none of the classical antifolates such as pyrimethamine (PYR), cycloguanil, or trimethoprim are effective as selective inhibitors of T. brucei DHFR (TbDHFR). In order to design effective drugs that target TbDHFR, co-crystal structures with bound antifolates were studied. On comparison with malarial Plasmodium falciparum DHFR (PfDHFR), the co-crystal structures of wild-type TbDHFR reveal greater structural similarities to a mutant PfDHFR causing antifolate resistance than the wild-type enzyme. TbDHFR imposes steric hindrance for rigid inhibitors like PYR around Thr86, which is equivalent to Ser108Asn of the malarial enzymes. In addition, a missing residue on TbDHFR active-site loop together with the presence of Ile51 widens its active site even further than the structural effect of Asn51Ile, which is observed in PfDHFR structures. The structural similarities are paralleled by the similarly poor affinities of the trypanosomal enzyme for rigid inhibitors. Mutations of TbDHFR at Thr86 resulted in 10-fold enhancement or 7-fold reduction in the rigid inhibitors affinities for Thr86Ser or Thr86Asn, respectively. The co-crystal structure of TbDHFR with a flexible antifolate WR99210 suggests that its greater affinity result from its ability to avoid such Thr86 clash and occupy the widened binding space similarly to what is observed in the PfDHFR structures. Natural resistance to antifolates of TbDHFR can therefore be explained, and potential antifolate chemotherapy of trypanosomiasis should be possible taking this into account.
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Affiliation(s)
- Jarunee Vanichtanankul
- National Center for Genetic Engineering and Biotechnology, National Science and Technology Development Agency, 113 Thailand Science Park, Paholyothin Road, Klong Luang, Pathumthani 12120, Thailand
- Department of Biochemistry and Center for Excellence in Protein Structure and Function, Faculty of Science, Mahidol University, Rama 6 Road, Bangkok 10400, Thailand
| | - Supannee Taweechai
- National Center for Genetic Engineering and Biotechnology, National Science and Technology Development Agency, 113 Thailand Science Park, Paholyothin Road, Klong Luang, Pathumthani 12120, Thailand
| | - Jirundon Yuvaniyama
- Department of Biochemistry and Center for Excellence in Protein Structure and Function, Faculty of Science, Mahidol University, Rama 6 Road, Bangkok 10400, Thailand
| | - Tirayut Vilaivan
- Department of Chemistry, Faculty of Science, Chulalongkorn University, Bangkok 10330, Thailand
| | - Penchit Chitnumsub
- National Center for Genetic Engineering and Biotechnology, National Science and Technology Development Agency, 113 Thailand Science Park, Paholyothin Road, Klong Luang, Pathumthani 12120, Thailand
| | - Sumalee Kamchonwongpaisan
- National Center for Genetic Engineering and Biotechnology, National Science and Technology Development Agency, 113 Thailand Science Park, Paholyothin Road, Klong Luang, Pathumthani 12120, Thailand
| | - Yongyuth Yuthavong
- National Center for Genetic Engineering and Biotechnology, National Science and Technology Development Agency, 113 Thailand Science Park, Paholyothin Road, Klong Luang, Pathumthani 12120, Thailand
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26
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Jorda R, Sacerdoti-Sierra N, Voller J, Havlíček L, Kráčalíková K, Nowicki MW, Nasereddin A, Kryštof V, Strnad M, Walkinshaw MD, Jaffe CL. Anti-leishmanial activity of disubstituted purines and related pyrazolo[4,3-d]pyrimidines. Bioorg Med Chem Lett 2011; 21:4233-7. [DOI: 10.1016/j.bmcl.2011.05.076] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2011] [Revised: 05/19/2011] [Accepted: 05/20/2011] [Indexed: 12/25/2022]
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27
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Mallari JP, Zhu F, Lemoff A, Kaiser M, Lu M, Brun R, Guy RK. Optimization of purine-nitrile TbcatB inhibitors for use in vivo and evaluation of efficacy in murine models. Bioorg Med Chem 2010; 18:8302-9. [DOI: 10.1016/j.bmc.2010.09.073] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2010] [Revised: 09/24/2010] [Accepted: 09/30/2010] [Indexed: 11/25/2022]
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28
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Probing the structure of Leishmania donovani chagasi DHFR-TS: comparative protein modeling and protein-ligand interaction studies. J Mol Model 2010; 16:1539-47. [PMID: 20174846 DOI: 10.1007/s00894-010-0649-0] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2009] [Accepted: 12/22/2009] [Indexed: 10/27/2022]
Abstract
Dihydrofolate reductase (DHFR) has been used successfully as a drug target in the area of anti-bacterial, anti-cancer and anti-malarial therapy. It also acts as a drug target for Leishmaniasis. Inhibition of DHFR leads to cell death through lack of thymine (nucleotide metabolism). Although the crystal structures of Leishmania major and Trypanosoma cruzi DHFR-thymidylate synthase (TS) have been resolved, to date there is no three-dimensional (3D)-structural information on DHFR-TS of Leishmania donovani chagasi, which causes visceral leishmaniasis. Our aim in this study was to model the 3D structure of L. donovani chagasi DHFR-TS, and to investigate the structural requirements for its inhibition. In this paper we describe a highly refined homology model of L. donovani chagasi DHFR-TS based on available crystallographic structures by using the Homology module of Insight II. Structural refinement and minimization of the generated L. donovani chagasi DHFR-TS model employed the Discover 3 module of Insight II and molecular dynamic simulations. The model was further validated through use of the PROCHECK, Verify_3D, PROSA, PSQS and ERRAT programs, which confirm that the model is reliable. Superimposition of the model structure with the templates L. major A chain, L. major B chain And T. cruzi A chain showed root mean square deviations of 0.69 A, 0.71 A and 1.11 A, respectively. Docking analysis of the L. donovani chagasi DHFR-TS model with methotrexate enabled us to identify specific residues, viz. Val156, Val30, Lys95, Lys75 and Arg97, within the L. donovani chagasi DHFR-TS binding pocket, that play an important role in ligand or substrate binding. Docking studies clearly indicated that these five residues are important determinants for binding as they have strong hydrogen bonding interactions with the ligand.
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29
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Gupta L, Sunduru N, Verma A, Srivastava S, Gupta S, Goyal N, Chauhan PMS. Synthesis and biological evaluation of new [1,2,4]triazino[5,6-b]indol-3-ylthio-1,3,5-triazines and [1,2,4]triazino[5,6-b]indol-3-ylthio-pyrimidines against Leishmania donovani. Eur J Med Chem 2010; 45:2359-65. [PMID: 20371140 DOI: 10.1016/j.ejmech.2010.02.015] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2009] [Revised: 01/29/2010] [Accepted: 02/04/2010] [Indexed: 11/24/2022]
Abstract
A series of [1,2,4]triazino[5,6-b]indol-3-ylthio-1,3,5-triazines and [1,2,4]triazino[5,6-b]indol-3-ylthio-pyrimidines were synthesized and screened for their in vitro antileishmanial activity against Leishmania donovani. Among all, 8 compounds have shown more than 90% inhibition against promastigotes and IC50 in the range of 4.01-57.78 microM against amastigotes. Compound 5, a triazino[5,6-b]indol-3-ylthio-1,3,5-triazine derivative was found to be the most active and least toxic with 20- & 10-fold more selectivity (S.I.=56.61) as compared to that of standard drugs pentamidine and sodium stibogluconate (SSG), respectively.
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Affiliation(s)
- Leena Gupta
- Division of Medicinal and Process Chemistry, Central Drug Research Institute, MG Road, Lucknow 226001, U.P., India
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30
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Planche AS, Scotti MT, Emerenciano VDP, López AG, Pérez EM, Uriarte E. Designing novel antitrypanosomal agents from a mixed graph-theoretical substructural approach. J Comput Chem 2009; 31:882-94. [DOI: 10.1002/jcc.21374] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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31
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Chemotherapy of leishmaniasis part-VIII: Synthesis and bioevaluation of novel chalcones. Eur J Med Chem 2008; 43:2473-8. [DOI: 10.1016/j.ejmech.2007.12.014] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2007] [Accepted: 12/11/2007] [Indexed: 11/20/2022]
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32
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Sienkiewicz N, Jarosławski S, Wyllie S, Fairlamb AH. Chemical and genetic validation of dihydrofolate reductase-thymidylate synthase as a drug target in African trypanosomes. Mol Microbiol 2008; 69:520-33. [PMID: 18557814 PMCID: PMC2610392 DOI: 10.1111/j.1365-2958.2008.06305.x] [Citation(s) in RCA: 60] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
The phenotypes of single- (SKO) and double-knockout (DKO) lines of dihydrofolate reductase–thymidylate synthase (DHFR–TS) of bloodstream Trypanosoma brucei were evaluated in vitro and in vivo. Growth of SKO in vitro is identical to wild-type (WT) cells, whereas DKO has an absolute requirement for thymidine. Removal of thymidine from the medium triggers growth arrest in S phase, associated with gross morphological changes, followed by cell death after 60 h. DKO is unable to infect mice, whereas the virulence of SKO is similar to WT. Normal growth and virulence could be restored by transfection of DKO with T. brucei DHFR–TS, but not with Escherichia coli TS. As pteridine reductase (PTR1) levels are unchanged in SKO and DKO cells, PTR1 is not able to compensate for loss of DHFR activity. Drugs such as raltitrexed or methotrexate with structural similarity to folic acid are up to 300-fold more potent inhibitors of WT cultured in a novel low-folate medium, unlike hydrophobic antifols such as trimetrexate or pyrimethamine. DKO trypanosomes show reduced sensitivity to these inhibitors ranging from twofold for trimetrexate to >10 000-fold for raltitrexed. These data demonstrate that DHFR–TS is essential for parasite survival and represents a promising target for drug discovery.
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Affiliation(s)
- Natasha Sienkiewicz
- Division of Biological Chemistry & Drug Discovery, College of Life Sciences, University of Dundee, Dundee, UK
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33
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Suryawanshi SN, Pandey S, Bhatt BA, Gupta S. Chemotherapy of leishmaniasis Part VI: Synthesis and bioevaluation of some novel terpenyl S,N- and N,N-acetals. Eur J Med Chem 2007; 42:511-6. [PMID: 17178176 DOI: 10.1016/j.ejmech.2006.09.016] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2006] [Revised: 09/16/2006] [Accepted: 09/21/2006] [Indexed: 10/23/2022]
Abstract
Some novel terpene based oxoketene S,N-acetals 2(a-g) and N,N-acetals 3(a-c) have been synthesized from oxoketene dithioacetal 1. The compounds were screened for their in vivo antileishmanial activity. Some of the compounds showed 50-70% inhibition in the hamster model.
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Affiliation(s)
- S N Suryawanshi
- Division of Medicinal Chemistry, Central Drug Research Institute, Chatter Manzil, Lucknow 226001, Uttar Pradesh, India.
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Abstract
Diseases caused by tropical parasites affect hundreds of millions of people worldwide but have been largely neglected for drug development because they affect poor people in poor regions of the world. Most of the current drugs used to treat these diseases are decades old and have many limitations, including the emergence of drug resistance. This review will summarize efforts to reinvigorate the drug development pipeline for these diseases, which is driven in large part by support from major philanthropies. The organisms responsible for these diseases have a fascinating biology, and many potential biochemical targets are now apparent. These neglected diseases present unique challenges to drug development that are being addressed by new consortia of scientists from academia and industry.
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Affiliation(s)
- Adam R Renslo
- Department of Pharmaceutical Chemistry and the Small Molecule Discovery Center, University of California-San Francisco, San Francisco, CA 94158, USA
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35
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Barrett MP, Gilbert IH. Targeting of toxic compounds to the trypanosome's interior. ADVANCES IN PARASITOLOGY 2006; 63:125-83. [PMID: 17134653 DOI: 10.1016/s0065-308x(06)63002-9] [Citation(s) in RCA: 50] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
Drugs can be targeted into African trypanosomes by exploiting carrier proteins at the surface of these parasites. This has been clearly demonstrated in the case of the melamine-based arsenical and the diamidine classes of drug that are already in use in the treatment of human African trypanosomiasis. These drugs can enter via an aminopurine transporter, termed P2, encoded by the TbAT1 gene. Other toxic compounds have also been designed to enter via this transporter. Some of these compounds enter almost exclusively through the P2 transporter, and hence loss of the P2 transporter leads to significant resistance to these particular compounds. It now appears, however, that some diamidines and melaminophenylarsenicals may also be taken up by other routes (of yet unknown function). These too may be exploited to target new drugs into trypanosomes. Additional purine nucleoside and nucleobase transporters have also been subverted to deliver toxic agents to trypanosomes. Glucose and amino acid transporters too have been investigated with a view to manipulating them to carry toxins into Trypanosoma brucei, and recent work has demonstrated that aquaglyceroporins may also have considerable potential for drug-targeting. Transporters, including those that carry lipids and vitamins such as folate and other pterins also deserve more attention in this regard. Some drugs, for example suramin, appear to enter via routes other than plasma-membrane-mediated transport. Receptor-mediated endocytosis has been proposed as a possible way in for suramin. Endocytosis also appears to be crucial in targeting natural trypanocides, such as trypanosome lytic factor (TLF) (apolipoprotein L1), into trypanosomes and this offers an alternative means of selectively targeting toxins to the trypanosome's interior. Other compounds may be induced to enter by increasing their capacity to diffuse over cell membranes; in this case depending exclusively on selective activity within the cell rather than selective uptake to impart selective toxicity. This review outlines studies that have aimed to exploit trypanosome nutrient uptake routes to selectively carry toxins into these parasites.
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Affiliation(s)
- Michael P Barrett
- Division of Infection & Immunity, Institute of Biomedical and Life Sciences, Glasgow Biomedical Research Centre, University of Glasgow, Glasgow G12 8QQ, UK
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36
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Chandra N, Pandey S, Suryawanshi SN, Gupta S. Chemotherapy of leishmaniasis part III: synthesis and bioevaluation of novel aryl substituted terpenyl pyrimidines as antileishmanial agents. Eur J Med Chem 2006; 41:779-85. [PMID: 16697490 DOI: 10.1016/j.ejmech.2006.02.004] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2004] [Revised: 01/31/2006] [Accepted: 02/16/2006] [Indexed: 11/19/2022]
Abstract
Some aryl substituted terpenyl pyrimidines 4 (a-p) have been synthesized using novel synthetic methods. The compounds were screened for in vitro antileishmanial activity against promastigotes. Compounds 4c, 4i and 4l showed IC(50) values as 35, 35 and 25 microg ml(-1).
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Affiliation(s)
- Naveen Chandra
- Division of Medicinal Chemistry, Central Drug Research Institute, Lucknow 226001, India
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37
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Senkovich O, Bhatia V, Garg N, Chattopadhyay D. Lipophilic antifolate trimetrexate is a potent inhibitor of Trypanosoma cruzi: prospect for chemotherapy of Chagas' disease. Antimicrob Agents Chemother 2005; 49:3234-8. [PMID: 16048931 PMCID: PMC1196212 DOI: 10.1128/aac.49.8.3234-3238.2005] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023] Open
Abstract
Trypanosoma cruzi, a protozoan parasite, is the causative agent for Chagas' disease, which poses serious public health problem in Latin America. The two drugs available for the treatment of this disease are effective only against recent infections and are toxic. Dihydrofolate reductase (DHFR) has a proven track record as a drug target. The lipophilic antifolate trimetrexate (TMQ), which is an FDA-approved drug for the treatment of Pneumocystis carinii infection in AIDS patients, is a potent inhibitor of T. cruzi DHFR activity, with an inhibitory constant of 6.6 nM. The compound is also highly effective in killing T. cruzi parasites. The 50 and 90% lethal dose values against the trypomastigote are 19 and 36 nM, and the corresponding values for the amastigote form are 26 and 72 nM, respectively. However, as TMQ is also a good inhibitor of human DHFR, further improvement of the selectivity of this drug would be preferable. Identification of a novel antifolate selective against T. cruzi would open up new therapeutic avenues for treatment of Chagas' disease.
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Affiliation(s)
- Olga Senkovich
- University of Alabama at Birmingham, CBSE-250, 1025 18th Street South, Birmingham, AL 35294, USA
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38
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Pandey S, Suryawanshi SN, Gupta S, Srivastava VML. Chemotherapy of leishmaniasis part II: synthesis and bioevaluation of substituted arylketene dithioacetals as antileishmanial agents. Eur J Med Chem 2005; 40:751-6. [PMID: 15907348 DOI: 10.1016/j.ejmech.2005.02.007] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2004] [Revised: 02/14/2005] [Accepted: 02/24/2005] [Indexed: 10/25/2022]
Abstract
Some novel aryl substituted ketene dithioacetals have been synthesized using novel synthetic methods. The compounds were screened against Leishmania donovani in hamsters for their activity profile. Some of the compounds inhibited 50-65% parasite growth at 50 mg kg(-1) x 5 days.
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Affiliation(s)
- Susmita Pandey
- Division of Medicinal Chemistry, Central Drug Research Institute, Lucknow, India
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39
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Affiliation(s)
- Ivan M Kompis
- ARPIDA Ltd, Dammstrasse 36, 4142 Münchenstein, Switzerland
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40
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Khabnadideh S, Pez D, Musso A, Brun R, Pérez LMR, González-Pacanowska D, Gilbert IH. Design, synthesis and evaluation of 2,4-diaminoquinazolines as inhibitors of trypanosomal and leishmanial dihydrofolate reductase. Bioorg Med Chem 2005; 13:2637-49. [PMID: 15755663 DOI: 10.1016/j.bmc.2005.01.025] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2004] [Accepted: 01/14/2005] [Indexed: 11/28/2022]
Abstract
This paper describes the design, synthesis and evaluation of a series of 2,4-diaminoquinazolines as inhibitors of leishmanial and trypanosomal dihydrofolate reductase. Compounds were designed by a generating virtual library of compounds and docking them into the enzyme active site. Following their synthesis, they were found to be potent and selective inhibitors of leishmanial dihydrofolate reductase. The compounds were also found to have potent activity against Trypanosoma brucei rhodesiense, a causative organism of African trypanosomiasis and also against Trypanosoma cruzi, the causative organism of Chagas disease. There was significantly lower activity against Leishmania donovani, one of the causative organisms of leishmaniasis.
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Affiliation(s)
- Soghra Khabnadideh
- Welsh School of Pharmacy, Cardiff University, Redwood Building, King Edward VII Avenue, Cardiff, CF10 3XF, UK
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41
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Savel J, Durand R. Dihydrofolate reductase inhibitors: new developments in antiparasitic chemotherapy. Expert Opin Ther Pat 2005. [DOI: 10.1517/13543776.11.8.1285] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
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42
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Pandey S, Suryawanshi SN, Gupta S, Srivastava VML. Synthesis and antileishmanial profile of some novel terpenyl pyrimidines. Eur J Med Chem 2004; 39:969-73. [PMID: 15501546 DOI: 10.1016/j.ejmech.2004.03.007] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2003] [Revised: 03/05/2004] [Accepted: 03/11/2004] [Indexed: 11/28/2022]
Abstract
Some novel terpenyl pyrimidine derivatives 2(a-d) and 6(a-b) have been synthesised from alpha/beta-ionone keteneacetals 1 and 5. The terpenyl pyrimidine 2e has been synthesised from beta-ionone 3 in two steps in quantitative yield. The pyrimidine derivatives were screened for in-vivo antilesihmanial activity. The compounds 2d, 2e, 6a and 6b showed promising in-vivo antileishmanial activity.
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Affiliation(s)
- Susmita Pandey
- Division of Medicinal Chemistry, Central Drug Research Institute, Lucknow, India
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43
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Yeboah FK, Alli I, Yaylayan VA, Yasuo K, Chowdhury SF, Purisima EO. Effect of limited solid-state glycation on the conformation of lysozyme by ESI-MSMS peptide mapping and molecular modeling. Bioconjug Chem 2004; 15:27-34. [PMID: 14733580 DOI: 10.1021/bc034083v] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Although protein glycation has been implicated in the alteration of protein functionality, both in vivo (in biological systems) and in vitro (in food systems), the effect of the protein-bound glycan moiety on the structure/conformation of proteins that result in the modification of functionality is not clear. In this article, we report a study of the conformational changes of glycated lysozyme using LC-ESI-MSMS peptide mapping, and molecular modeling. A comparison of the RP-HPLC of the tryptic digests of unglycated and glycated lysozyme showed markedly different chromatographic profiles. Analysis of the peptide composition of the chromatographic fractions of the tryptic digests revealed that glycation of lysozyme resulted in the modification of its conformation. Glycation-induced changes in the conformation of lysozyme resulted in the exposure of its active site region to increased proteolytic activity of trypsin. Molecular simulation of triglycated lysozyme also showed that limited glycation of lysozyme caused reorientation of the active site residues (Arg 45, Arg 68, Asn 44, and Trp 62) and increased solvent accessibility into the active site region of the protein. The results of the modeling experiment corroborated the results of the RP-HPLC and ESI-MSMS peptide mapping.
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Affiliation(s)
- Faustinus K Yeboah
- Biotechnology Research Institute, 6100 Royalmount Avenue, Montreal, Quebec, Canada H4P-2R2.
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44
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Otzen T, Wempe EG, Kunz B, Bartels R, Lehwark-Yvetot G, Hänsel W, Schaper KJ, Seydel JK. Folate-Synthesizing Enzyme System as Target for Development of Inhibitors and Inhibitor Combinations against Candida albicansSynthesis and Biological Activity of New 2,4-Diaminopyrimidines and 4‘-Substituted 4-Aminodiphenyl Sulfones. J Med Chem 2003; 47:240-53. [PMID: 14695838 DOI: 10.1021/jm030931w] [Citation(s) in RCA: 114] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The paper describes the design, synthesis, and testing of inhibitors of folate-synthesizing enzymes and of whole cell cultures of Candida albicans. The target enzymes used were dihydropteroic acid synthase (SYN) and dihydrofolate reductase (DHFR). Several series of new 2,4-diaminopyrimidines were synthesized and tested as inhibitors of DHFR and compared with their activity against DHFR derived from mycobacteria and Escherichia coli. To test for selectivity, also rat DHFR was used. A series of substituted 4-aminodiphenyl sulfones was tested for inhibitory activity against SYN and the I(50) values compared to those obtained previously against Plasmodium berghei- and E. coli-derived SYN. Surprisingly, QSAR equations show very similar structural dependencies. To find an explanation for the large difference in the I(50) values observed for enzyme inhibition (SYN, DHFR) and for inhibition of cell cultures of Candida, mutant strains with overexpressed efflux pumps and strains in which such pumps are deleted were included in the study and the MICs compared. Efflux pumps were responsible for the low activity of some of the tested derivatives, others showed no increase in activity after pumps were knocked out. In this case it may be speculated that these derivatives are not able to enter the cells.
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Affiliation(s)
- Thomas Otzen
- Division of Structural Biochemistry, Research Center Borstel, Leibniz Center for Medicine and Biosciences, Parkallee 1-40, D-23845 Borstel, Germany
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45
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Pez D, Leal I, Zuccotto F, Boussard C, Brun R, Croft SL, Yardley V, Ruiz Perez LM, Gonzalez Pacanowska D, Gilbert IH. 2,4-Diaminopyrimidines as inhibitors of Leishmanial and Trypanosomal dihydrofolate reductase. Bioorg Med Chem 2003; 11:4693-711. [PMID: 14556785 DOI: 10.1016/j.bmc.2003.08.012] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
This paper describes the synthesis of 4'-substituted and 3',4'-disubstituted 5-benzyl-2,4-diaminopyrimidines as selective inhibitors of leishmanial and trypanosomal dihydrofolate reductase. Compounds were then assayed against the recombinant parasite and human enzymes. Some of the compounds showed good activity. They were also tested against the intact parasites using in vitro assays. Good activity was found against Trypanosoma cruzi, moderate activity against Trypanosoma brucei and Leishmania donovani. Molecular modeling was undertaken to explain the results. The leishmanial enzyme was found to have a more extensive lipophilic binding region in the active site than the human enzyme. Compounds which bound within the pocket showed the highest selectivity.
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Affiliation(s)
- Didier Pez
- Welsh School of Pharmacy, Cardiff University, Redwood Building, King Edward VII Avenue, CF10 3XF Cardiff, UK
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46
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Murphy EF, Gilmour SG, Crabbe MJC. Effective experimental design: enzyme kinetics in the bioinformatics era. Drug Discov Today 2002; 7:S187-91. [PMID: 12546904 DOI: 10.1016/s1359-6446(02)02384-x] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Acquiring details about the kinetic parameters of enzymes is crucial to both drug development and clinical diagnosis. The correct design of an experiment is crucial to collecting data suitable for analysis, modelling and deriving the correct information. As classical design methods are not targeted to the more complex kinetics now frequently studied, further work is required to estimate parameters of such models with low variance. This review examines the different options available to produce major gains in information, productivity and the accuracy of each experiment.
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Affiliation(s)
- Emma F Murphy
- Bioinformatics, Division of Cell and Molecular Biology, School of Animal and Microbial Sciences, The University of Reading, Whiteknights, Reading, Berkshire RG6 6AJ, UK.
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47
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Abstract
Current treatments for the parasitic disease leishmaniasis are unsatisfactory due to their route of administration, toxicity and expense. Resistance is also developing to first-line antimonial drugs. Fortunately, a handful of antileishmanial agents, such as the orally available compound miltefosine, are currently in clinical trials. In addition, several promising drug targets and lead molecules are being studied with the goal of developing new antileishmanial agents. Drug candidates have been identified through the continued investigation of parasite sterol metabolism and parasite proteases. New antileishmanial molecules have also been discovered through the study of novel targets and pathways, such as the bisphosphonate inhibitors of isoprenoid biosynthesis. This review presents a synopsis of the drug targets and lead compounds that have been investigated over the last few years against leishmaniasis, gives a perspective on the chemotherapeutic potential of each and discusses some of the obstacles to antileishmanial drug development.
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Affiliation(s)
- Karl A Werbovetz
- Division of Medicinal Chemistry and Pharmacognosy, College of Pharmacy, Ohio State University, 500 West 12th Avenue, Columbus, OH 43210, USA.
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48
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Gilbert IH. Inhibitors of dihydrofolate reductase in Leishmania and trypanosomes. BIOCHIMICA ET BIOPHYSICA ACTA 2002; 1587:249-57. [PMID: 12084467 DOI: 10.1016/s0925-4439(02)00088-1] [Citation(s) in RCA: 77] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
The protozoan diseases leishmaniasis, Chagas' disease and African trypanosomiasis are major health problems in many countries, particularly developing countries, and there are few drugs available to treat these diseases. Dihydrofolate reductase (DHFR) inhibitors have been used successfully in the treatment of a number of other diseases such as cancer, malaria and bacterial infections; however they have not been used for the treatment of these diseases. This article summarises studies on leishmanial and trypanosomal DHFR inhibitor development and evaluation. Possible mechanisms of resistance to DHFR inhibitors are also discussed.
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Affiliation(s)
- Ian H Gilbert
- Welsh School of Pharmacy, Cardiff University, Redwood Building, King Edward VII Avenue, Cardiff, UK.
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49
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Ouellette M, Drummelsmith J, El-Fadili A, Kündig C, Richard D, Roy G. Pterin transport and metabolism in Leishmania and related trypanosomatid parasites. Int J Parasitol 2002; 32:385-98. [PMID: 11849635 DOI: 10.1016/s0020-7519(01)00346-0] [Citation(s) in RCA: 75] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
The folate metabolic pathway has been exploited successfully for the development of antimicrobial and antineoplasic agents. Inhibitors of this pathway, however, are not useful against Leishmania and other trypanosomatids. Work on the mechanism of methotrexate resistance in Leishmania has dramatically increased our understanding of folate and pterin metabolism in this organism. The metabolic and cellular functions of the reduced form of folates and pterins are beginning to be established and this work has led to several unexpected findings. Moreover, the currently ongoing sequencing efforts on trypanosomatid genomes are suggesting the presence of several gene products that are likely to require folates and pterins. A number of the properties of folate and pterin metabolism are unique suggesting that these pathways are valid and worthwhile targets for drug development.
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Affiliation(s)
- Marc Ouellette
- Centre de recherche en Infectiologie du CHUL, 2705, boul. Laurier, QC, Sainte-Foy, Canada GIV 4G2.
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50
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Abstract
Drug resistance is complicating the treatment of parasitic diseases. We review here the basic mechanisms of parasite resistance in malaria, sleeping sickness, leishmaniasis and common helminthiases. Parasites resort to multiple biochemical means to achieve resistance and we have begun to isolate and characterize the genes/proteins implicated in resistance. Understanding drug resistance is essential for the control of parasitic diseases.
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Affiliation(s)
- M Ouellette
- Centre de Recherche en Infectiologie du Centre de Recherche du CHUL and Département de Microbiologie, Faculté de Médecine, Université Laval, Québec, Canada.
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