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van der Krift F, Zijlmans DW, Shukla R, Javed A, Koukos PI, Schwarz LLE, Timmermans-Sprang EP, Maas PE, Gahtory D, van den Nieuwboer M, Mol JA, Strous GJ, Bonvin AM, van der Stelt M, Veldhuizen EJ, Weingarth M, Vermeulen M, Klumperman J, Maurice MM. A novel antifolate suppresses growth of FPGS-deficient cells and overcomes methotrexate resistance. Life Sci Alliance 2023; 6:e202302058. [PMID: 37591722 PMCID: PMC10435995 DOI: 10.26508/lsa.202302058] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2023] [Revised: 08/07/2023] [Accepted: 08/07/2023] [Indexed: 08/19/2023] Open
Abstract
Cancer cells make extensive use of the folate cycle to sustain increased anabolic metabolism. Multiple chemotherapeutic drugs interfere with the folate cycle, including methotrexate and 5-fluorouracil that are commonly applied for the treatment of leukemia and colorectal cancer (CRC), respectively. Despite high success rates, therapy-induced resistance causes relapse at later disease stages. Depletion of folylpolyglutamate synthetase (FPGS), which normally promotes intracellular accumulation and activity of natural folates and methotrexate, is linked to methotrexate and 5-fluorouracil resistance and its association with relapse illustrates the need for improved intervention strategies. Here, we describe a novel antifolate (C1) that, like methotrexate, potently inhibits dihydrofolate reductase and downstream one-carbon metabolism. Contrary to methotrexate, C1 displays optimal efficacy in FPGS-deficient contexts, due to decreased competition with intracellular folates for interaction with dihydrofolate reductase. We show that FPGS-deficient patient-derived CRC organoids display enhanced sensitivity to C1, whereas FPGS-high CRC organoids are more sensitive to methotrexate. Our results argue that polyglutamylation-independent antifolates can be applied to exert selective pressure on FPGS-deficient cells during chemotherapy, using a vulnerability created by polyglutamylation deficiency.
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Affiliation(s)
- Felix van der Krift
- Center for Molecular Medicine and Oncode Institute, University Medical Center Utrecht, Utrecht, The Netherlands
| | - Dick W Zijlmans
- Department of Molecular Biology and Oncode Institute, Faculty of Science, Radboud Institute for Molecular Life Sciences, Radboud University Nijmegen, Nijmegen, The Netherlands
| | - Rhythm Shukla
- NMR Spectroscopy, Bijvoet Centre for Biomolecular Research, Department of Chemistry, Faculty of Science, Utrecht University, Utrecht, The Netherlands
| | - Ali Javed
- NMR Spectroscopy, Bijvoet Centre for Biomolecular Research, Department of Chemistry, Faculty of Science, Utrecht University, Utrecht, The Netherlands
- Division of Infectious Diseases and Immunology, Department of Biomolecular Health Sciences, Utrecht University, Utrecht, The Netherlands
| | - Panagiotis I Koukos
- Computational Structural Biology, Bijvoet Centre for Biomolecular Research, Faculty of Science, Department of Chemistry, Utrecht University, Utrecht, The Netherlands
| | - Laura LE Schwarz
- Center for Molecular Medicine and Oncode Institute, University Medical Center Utrecht, Utrecht, The Netherlands
| | | | - Peter Em Maas
- Specs Compound Handling B.V., Zoetermeer, The Netherlands
| | | | | | - Jan A Mol
- Department of Clinical Sciences of Companion Animals, Utrecht University, Utrecht, The Netherlands
| | - Ger J Strous
- Center for Molecular Medicine, Cell Biology, University Medical Center Utrecht, Utrecht, The Netherlands
| | - Alexandre Mjj Bonvin
- Computational Structural Biology, Bijvoet Centre for Biomolecular Research, Faculty of Science, Department of Chemistry, Utrecht University, Utrecht, The Netherlands
| | - Mario van der Stelt
- Department of Molecular Physiology and Oncode Institute, Leiden Institute of Chemistry, Leiden University, Leiden, The Netherlands
| | - Edwin Ja Veldhuizen
- Division of Infectious Diseases and Immunology, Department of Biomolecular Health Sciences, Utrecht University, Utrecht, The Netherlands
| | - Markus Weingarth
- NMR Spectroscopy, Bijvoet Centre for Biomolecular Research, Department of Chemistry, Faculty of Science, Utrecht University, Utrecht, The Netherlands
| | - Michiel Vermeulen
- Department of Molecular Biology and Oncode Institute, Faculty of Science, Radboud Institute for Molecular Life Sciences, Radboud University Nijmegen, Nijmegen, The Netherlands
| | - Judith Klumperman
- Center for Molecular Medicine, Cell Biology, University Medical Center Utrecht, Utrecht, The Netherlands
| | - Madelon M Maurice
- Center for Molecular Medicine and Oncode Institute, University Medical Center Utrecht, Utrecht, The Netherlands
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Synthesis, antitumor activities and functional mechanism of purine derivatives harboring phenyl moieties through three carbon bridges. Med Chem Res 2023. [DOI: 10.1007/s00044-023-03038-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/08/2023]
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Microwave synthesis and antimalarial screening of novel 4-amino benzoic acid (PABA)-substituted pyrimidine derivatives as Plasmodium falciparum dihydrofolate reductase inhibitors. 3 Biotech 2022; 12:170. [PMID: 35845109 PMCID: PMC9279537 DOI: 10.1007/s13205-022-03236-w] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2022] [Accepted: 06/18/2022] [Indexed: 11/28/2022] Open
Abstract
Antimalarial drug resistance is a major threat due to the emerging resistance to all the available drugs in the market. In an approach to develop alternative drugs, a novel class of Pf-DHFR inhibitors was developed using pyrimidine as the core nucleus and substituting the 4- and 6- positions with amines and 4-amino benzoic acid (PABA) to avoid the problem of drug resistance. The resultant compounds 3(a-j) after primary in silico screening and filtering were synthesized using microwave efficiently in high yield and reduced time period compared to conventional synthesis. The antimalarial assay was performed in vitro, against chloroquine-sensitive (3D7) and chloroquine-resistant (Dd2) strains of Plasmodium falciparum using chloroquine as a reference standard. The IC50 values were in the range of 5.26-106.76 µg/ml for 3D7 and in Dd2 the value ranges from 4.71 to 112.98 µg/ml. Compounds 3d, 3e, 3f and 3h showed significant antimalarial activity against both the strains of P. falciparum with no cytotoxicity against fibroblast cell line and 3f was found to be the most potent among them. The hemolysis assay of all the compounds in fresh erythrocytes showed insignificant hemolysis below 5% at a higher dose level. Hence, the present study suggests the possible utility of PABA-substituted pyrimidine scaffold for further development of new Pf-DHFR inhibitors. Supplementary Information The online version contains supplementary material available at 10.1007/s13205-022-03236-w.
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Abdolmaleki B, Maddah M. Screening of indole derivatives as the potent anticancer agents on dihydrofolate reductase: pharmaco-informatics and molecular dynamics simulation. J Biomol Struct Dyn 2022; 41:3667-3679. [PMID: 35318890 DOI: 10.1080/07391102.2022.2053745] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
Dihydrofolate reductase (DHFR) is a ubiquitous cellular enzyme involved in the biosynthesis of nucleotide and protein precursors, thus, the inhibition of human DHFR can be a promising strategy in cancer treatment. The design of effective anticancer drugs is an urgent need today according to the high spread of cancer. The indole molecule with diverse mechanisms of action and anticancer properties is one of the efficient pharmacophores in drug design. Hence, a virtual library of indole derivatives as a scaffold was selected for designing safer and more effective anticancer drugs against DHFR in this work. All indole derivatives utilized in the library design were selected regarding appreciable tumor growth inhibition. Structure-activity relationship (SAR), docking energy, ADMET (absorption, distribution, metabolism, excretion, and toxicity) parameters, and effective non-covalent interactions were used to identify potential anticancer with indole scaffold. Results showed a higher number of indole moieties provide a strong attachment to the DHFR binding pocket and therefore more effective anticancer activity. The indole scaffold in combination with dichlorobenzene improves DHFR inhibition whereas barbituric acid weakens inhibition activity. In the following to validate the docking results, Molecular dynamics (MD) simulation and molecular mechanics generalized-Born surface area (MM-GBSA) indicated the permanent stability of the selected ligands into the DHFR binding pocket and the key amino acids. Therefore, promising pharmacophores based on indole-DHFR interactions were discovered, and the outcome could be useful in guiding future in vitro and in vivo drug discovery in cancer medicine.Communicated by Ramaswamy H. Sarma.
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Affiliation(s)
- Behnaz Abdolmaleki
- Department of Chemistry, K.N.Toosi University of Technology, Tehran, Iran
| | - Mina Maddah
- Department of Chemistry, K.N.Toosi University of Technology, Tehran, Iran.,Super Computing Institute, University of Tehran, Tehran, Iran
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Wróbel A, Drozdowska D. Recent Design and Structure-Activity Relationship Studies on the Modifications of DHFR Inhibitors as Anticancer Agents. Curr Med Chem 2021; 28:910-939. [PMID: 31622199 DOI: 10.2174/0929867326666191016151018] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2019] [Revised: 09/25/2019] [Accepted: 09/27/2019] [Indexed: 11/22/2022]
Abstract
BACKGROUND Dihydrofolate reductase (DHFR) has been known for decades as a molecular target for antibacterial, antifungal and anti-malarial treatments. This enzyme is becoming increasingly important in the design of new anticancer drugs, which is confirmed by numerous studies including modelling, synthesis and in vitro biological research. This review aims to present and discuss some remarkable recent advances in the research of new DHFR inhibitors with potential anticancer activity. METHODS The scientific literature of the last decade on the different types of DHFR inhibitors has been searched. The studies on design, synthesis and investigation structure-activity relationships were summarized and divided into several subsections depending on the leading molecule and its structural modification. Various methods of synthesis, potential anticancer activity and possible practical applications as DHFR inhibitors of new chemical compounds were described and discussed. RESULTS This review presents the current state of knowledge on the modification of known DHFR inhibitors and the structures and searches for about eighty new molecules, designed as potential anticancer drugs. In addition, DHFR inhibitors acting on thymidylate synthase (TS), carbon anhydrase (CA) and even DNA-binding are presented in this paper. CONCLUSION Thorough physicochemical characterization and biological investigations highlight the structure-activity relationship of DHFR inhibitors. This will enable even better design and synthesis of active compounds, which would have the expected mechanism of action and the desired activity.
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Affiliation(s)
- Agnieszka Wróbel
- Department of Organic Chemistry, Faculty of Pharmacy, Medical University, Białystok, Poland
| | - Danuta Drozdowska
- Department of Organic Chemistry, Faculty of Pharmacy, Medical University, Białystok, Poland
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Wróbel A, Baradyn M, Ratkiewicz A, Drozdowska D. Synthesis, Biological Activity, and Molecular Dynamics Study of Novel Series of a Trimethoprim Analogs as Multi-Targeted Compounds: Dihydrofolate Reductase (DHFR) Inhibitors and DNA-Binding Agents. Int J Mol Sci 2021; 22:3685. [PMID: 33916202 PMCID: PMC8037161 DOI: 10.3390/ijms22073685] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2021] [Revised: 03/27/2021] [Accepted: 03/29/2021] [Indexed: 01/07/2023] Open
Abstract
Eighteen previously undescribed trimethoprim (TMP) analogs containing amide bonds (1-18) were synthesized and compared with TMP, methotrexate (MTX), and netropsin (NT). These compounds were designed as potential minor groove binding agents (MGBAs) and inhibitors of human dihydrofolate reductase (hDHFR). The all-new derivatives were obtained via solid phase synthesis using 4-nitrophenyl Wang resin. Data from the ethidium displacement test confirmed their DNA-binding capacity. Compounds 13-14 (49.89% and 43.85%) and 17-18 (41.68% and 42.99%) showed a higher binding affinity to pBR322 plasmid than NT. The possibility of binding in a minor groove as well as determination of association constants were performed using calf thymus DNA, T4 coliphage DNA, poly (dA-dT)2, and poly (dG-dC)2. With the exception of compounds 9 (IC50 = 56.05 µM) and 11 (IC50 = 55.32 µM), all of the compounds showed better inhibitory properties against hDHFR than standard, which confirms that the addition of the amide bond into the TMP structures increases affinity towards hDHFR. Derivatives 2, 6, 13, 14, and 16 were found to be the most potent hDHFR inhibitors. This molecular modelling study shows that they interact strongly with a catalytically important residue Glu-30.
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Affiliation(s)
- Agnieszka Wróbel
- Department of Organic Chemistry, Medical University of Bialystok, 15-222 Bialystok, Poland;
| | - Maciej Baradyn
- Department of Physical Chemistry, Institute of Chemistry, University of Bialystok, 15-245 Bialystok, Poland; (M.B.); (A.R.)
| | - Artur Ratkiewicz
- Department of Physical Chemistry, Institute of Chemistry, University of Bialystok, 15-245 Bialystok, Poland; (M.B.); (A.R.)
| | - Danuta Drozdowska
- Department of Organic Chemistry, Medical University of Bialystok, 15-222 Bialystok, Poland;
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Wróbel A, Maliszewski D, Baradyn M, Drozdowska D. Trimethoprim: An Old Antibacterial Drug as a Template to Search for New Targets. Synthesis, Biological Activity and Molecular Modeling Study of Novel Trimethoprim Analogs. Molecules 2019; 25:molecules25010116. [PMID: 31892256 PMCID: PMC6983048 DOI: 10.3390/molecules25010116] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2019] [Revised: 12/21/2019] [Accepted: 12/24/2019] [Indexed: 01/15/2023] Open
Abstract
A new series of trimethoprim (TMP) analogs containing amide bonds (1–6) have been synthesized. Molecular docking, as well as dihydrofolate reductase (DHFR) inhibition assay were used to confirm their affinity to bind dihydrofolate reductase enzyme. Data from the ethidium displacement test showed their DNA-binding capacity. Tests confirming the possibility of DNA binding in a minor groove as well as determination of the association constants were performed using calf thymus DNA, T4 coliphage DNA, poly (dA-dT)2 and poly (dG-dC)2. Additionally, the mechanism of action of the new compounds was studied. In conclusion, some of our new analogs inhibited DHFR activity more strongly than TMP did, which confirms, that the addition of amide bonds into the analogs of TMP increases their affinity towards DHFR.
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Affiliation(s)
- Agnieszka Wróbel
- Department of Organic Chemistry, Medical University of Bialystok, 15222 Bialystok, Poland; (D.M.); (D.D.)
- Correspondence: ; Tel.: +50-253-3188
| | - Dawid Maliszewski
- Department of Organic Chemistry, Medical University of Bialystok, 15222 Bialystok, Poland; (D.M.); (D.D.)
| | - Maciej Baradyn
- Department of Physical Chemistry, University of Bialystok, Institute of Chemistry, 15245 Bialystok, Poland;
| | - Danuta Drozdowska
- Department of Organic Chemistry, Medical University of Bialystok, 15222 Bialystok, Poland; (D.M.); (D.D.)
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Trimethoprim and other nonclassical antifolates an excellent template for searching modifications of dihydrofolate reductase enzyme inhibitors. J Antibiot (Tokyo) 2019; 73:5-27. [PMID: 31578455 PMCID: PMC7102388 DOI: 10.1038/s41429-019-0240-6] [Citation(s) in RCA: 70] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2019] [Revised: 08/07/2019] [Accepted: 08/22/2019] [Indexed: 12/17/2022]
Abstract
The development of new mechanisms of resistance among pathogens, the occurrence and transmission of genes responsible for antibiotic insensitivity, as well as cancer diseases have been a serious clinical problem around the world for over 50 years. Therefore, intense searching of new leading structures and active substances, which may be used as new drugs, especially against strain resistant to all available therapeutics, is very important. Dihydrofolate reductase (DHFR) has attracted a lot of attention as a molecular target for bacterial resistance over several decades, resulting in a number of useful agents. Trimethoprim (TMP), (2,4-diamino-5-(3′,4′,5′-trimethoxybenzyl)pyrimidine) is the well-known dihydrofolate reductase inhibitor and one of the standard antibiotics used in urinary tract infections (UTIs). This review highlights advances in design, synthesis, and biological evaluations in structural modifications of TMP as DHFR inhibitors. In addition, this report presents the differences in the active site of human and pathogen DHFR. Moreover, an excellent review of DHFR inhibition and their relevance to antimicrobial and parasitic chemotherapy was presented.
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Rana RM, Rampogu S, Zeb A, Son M, Park C, Lee G, Yoon S, Baek A, Parameswaran S, Park SJ, Lee KW. In Silico Study Probes Potential Inhibitors of Human Dihydrofolate Reductase for Cancer Therapeutics. J Clin Med 2019; 8:jcm8020233. [PMID: 30754680 PMCID: PMC6406960 DOI: 10.3390/jcm8020233] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2018] [Revised: 02/05/2019] [Accepted: 02/08/2019] [Indexed: 01/10/2023] Open
Abstract
Dihydrofolate reductase (DHFR) is an essential cellular enzyme and thereby catalyzes thereduction of dihydrofolate to tetrahydrofolate (THF). In cancer medication, inhibition of humanDHFR (hDHFR) remains a promising strategy, as it depletes THF and slows DNA synthesis and cellproliferation. In the current study, ligand-based pharmacophore modeling identified and evaluatedthe critical chemical features of hDHFR inhibitors. A pharmacophore model (Hypo1) was generatedfrom known inhibitors of DHFR with a correlation coefficient (0.94), root mean square (RMS)deviation (0.99), and total cost value (125.28). Hypo1 was comprised of four chemical features,including two hydrogen bond donors (HDB), one hydrogen bond acceptor (HBA), and onehydrophobic (HYP). Hypo1 was validated using Fischer's randomization, test set, and decoy setvalidations, employed as a 3D query in a virtual screening at Maybridge, Chembridge, Asinex,National Cancer Institute (NCI), and Zinc databases. Hypo1-retrieved compounds were filtered byan absorption, distribution, metabolism, excretion, and toxicity (ADMET) assessment test andLipinski's rule of five, where the drug-like hit compounds were identified. The hit compounds weredocked in the active site of hDHFR and compounds with Goldfitness score was greater than 44.67(docking score for the reference compound), clustering analysis, and hydrogen bond interactionswere identified. Furthermore, molecular dynamics (MD) simulation identified three compounds asthe best inhibitors of hDHFR with the lowest root mean square deviation (1.2 Å to 1.8 Å), hydrogenbond interactions with hDHFR, and low binding free energy (-127 kJ/mol to -178 kJ/mol). Finally,the toxicity prediction by computer (TOPKAT) affirmed the safety of the novel inhibitors of hDHFRin human body. Overall, we recommend novel hit compounds of hDHFR for cancer and rheumatoidarthritis chemotherapeutics.
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Affiliation(s)
- Rabia Mukhtar Rana
- Division of Life Sciences, Division of Applied Life Science (BK21 Plus), Research Institute of NaturalScience (RINS), Gyeongsang National University (GNU), 501 Jinju-daero, Jinju 52828, Korea.
| | - Shailima Rampogu
- Division of Life Sciences, Division of Applied Life Science (BK21 Plus), Research Institute of NaturalScience (RINS), Gyeongsang National University (GNU), 501 Jinju-daero, Jinju 52828, Korea.
| | - Amir Zeb
- Division of Life Sciences, Division of Applied Life Science (BK21 Plus), Research Institute of NaturalScience (RINS), Gyeongsang National University (GNU), 501 Jinju-daero, Jinju 52828, Korea.
| | - Minky Son
- Division of Life Sciences, Division of Applied Life Science (BK21 Plus), Research Institute of NaturalScience (RINS), Gyeongsang National University (GNU), 501 Jinju-daero, Jinju 52828, Korea.
| | - Chanin Park
- Division of Life Sciences, Division of Applied Life Science (BK21 Plus), Research Institute of NaturalScience (RINS), Gyeongsang National University (GNU), 501 Jinju-daero, Jinju 52828, Korea.
| | - Gihwan Lee
- Division of Life Sciences, Division of Applied Life Science (BK21 Plus), Research Institute of NaturalScience (RINS), Gyeongsang National University (GNU), 501 Jinju-daero, Jinju 52828, Korea.
| | - Sanghwa Yoon
- Division of Life Sciences, Division of Applied Life Science (BK21 Plus), Research Institute of NaturalScience (RINS), Gyeongsang National University (GNU), 501 Jinju-daero, Jinju 52828, Korea.
| | - Ayoung Baek
- Division of Life Sciences, Division of Applied Life Science (BK21 Plus), Research Institute of NaturalScience (RINS), Gyeongsang National University (GNU), 501 Jinju-daero, Jinju 52828, Korea.
| | - Sarvanan Parameswaran
- Division of Life Sciences, Division of Applied Life Science (BK21 Plus), Research Institute of NaturalScience (RINS), Gyeongsang National University (GNU), 501 Jinju-daero, Jinju 52828, Korea.
| | - Seok Ju Park
- Department of Internal Medicine, College of Medicine, Busan Paik Hospital, Inje University,Busan 47392, Korea.
| | - Keun Woo Lee
- Division of Life Sciences, Division of Applied Life Science (BK21 Plus), Research Institute of NaturalScience (RINS), Gyeongsang National University (GNU), 501 Jinju-daero, Jinju 52828, Korea.
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Synthesis and evaluation of new 2,6-diamino-5-hetarylpyrimidines as inhibitors of dihydrofolate reductase. MONATSHEFTE FUR CHEMIE 2018. [DOI: 10.1007/s00706-017-2032-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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Paulsen JL, Bendel SD, Anderson AC. Crystal structures of Candida albicans dihydrofolate reductase bound to propargyl-linked antifolates reveal the flexibility of active site loop residues critical for ligand potency and selectivity. Chem Biol Drug Des 2011; 78:505-12. [PMID: 21726415 PMCID: PMC3171590 DOI: 10.1111/j.1747-0285.2011.01169.x] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
Candida albicans and Candida glabrata cause fungal bloodstream infections that are associated with significant mortality. As part of an effort to develop potent and selective antifolates that target dihydrofolate reductase (DHFR) from Candida species, we report three ternary crystal structures of C. albicans DHFR (CaDHFR) bound to novel propargyl-linked analogs. Consistent with earlier modeling results, these structures show that hydrophobic pockets in the binding site may be exploited to increase ligand potency. The crystal structures also confirm that loop residues Thr 58- Phe 66, which flank the active site and influence ligand potency and selectivity, adopt multiple conformations. To aid the development of a dual Candida spp. inhibitor, three new crystal structures of C. glabrata DHFR (CgDHFR) bound to similar ligands as those bound in the ternary structures of CaDHFR are also reported here. Loop residues 58-66 in CgDHFR and human DHFR are 1 and 3 Å closer to the folate binding site, respectively, than loop residues in CaDHFR, suggesting that a properly size ligand could be a potent and selective dual inhibitor of CaDHFR and CgDHFR.
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Affiliation(s)
| | | | - Amy C. Anderson
- Corresponding author: Amy C. Anderson, Dept. of Pharmaceutical Sciences, University of Connecticut, 69 N. Eagleville Rd., Storrs, CT 06269, , phone: (860)486-6145, fax: (860)486-6857
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