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Perveen S, Negi A, Saini S, Gangwar A, Sharma R. Identification of Chemical Scaffolds Targeting Drug-Resistant and Latent Mycobacterium tuberculosis through High-Throughput Whole-Cell Screening. ACS Infect Dis 2024; 10:513-526. [PMID: 38238154 DOI: 10.1021/acsinfecdis.3c00463] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/10/2024]
Abstract
Identification of structurally unique chemical entities targeting unexplored bacterial targets is a prerequisite to combat increasing drug resistance against Mycobacterium tuberculosis. This study employed a whole-cell screening approach as an initial filter to scrutinize a 10,000-compound chemical library, resulting in the discovery of seven potent compounds with MIC values ranging from 1.56 to 25 μM. These compounds were categorized into four distinct chemical groups. Remarkably, they demonstrated efficacy against drug-resistant and nonreplicating tuberculosis strains, highlighting their effectiveness across different infection states. With a favorable selectivity index (>10), these compounds showed a safe therapeutic range and exhibited potency in an intracellular model of Mtb infection, mimicking the in vivo setup. Combining these identified hits with established anti-TB drugs revealed additive effects with rifampicin, isoniazid, and bedaquiline. Notably, IIIM-IDD-01 exhibited synergy with isoniazid and bedaquiline, likely due to their complementary mechanisms of targeting Mtb. Most potent hits, IIIM-IDD-01 and IIIM-IDD-02, displayed time- and concentration-dependent killing of Mtb. Mechanistic insights were sought through SEM and docking studies, although comprehensive evaluation is ongoing to unravel the hits' specific targets and modes of action. The hits demonstrated favorable pharmacokinetic properties (ADME-Tox) and showed a low risk of adverse effects, along with a predicted high level of oral bioavailability. These promising hits can serve as an initial basis for subsequent medicinal chemistry endeavors aimed at developing a new series of anti-TB agents. Moreover, the study affirms the significance of high-throughput in vitro assays for the TB drug discovery. It also emphasizes the necessity of targeting diverse TB strains to address the heterogeneity of tuberculosis bacteria.
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Affiliation(s)
- Summaya Perveen
- Infectious Diseases Division, CSIR- Indian Institute of Integrative Medicine, Jammu 180001, India
- Academy of Scientific and Innovative Research (AcSIR), Ghaziabad 201002, India
| | - Anjali Negi
- Infectious Diseases Division, CSIR- Indian Institute of Integrative Medicine, Jammu 180001, India
- Academy of Scientific and Innovative Research (AcSIR), Ghaziabad 201002, India
| | - Sapna Saini
- Infectious Diseases Division, CSIR- Indian Institute of Integrative Medicine, Jammu 180001, India
- Academy of Scientific and Innovative Research (AcSIR), Ghaziabad 201002, India
| | - Anjali Gangwar
- Infectious Diseases Division, CSIR- Indian Institute of Integrative Medicine, Jammu 180001, India
- Academy of Scientific and Innovative Research (AcSIR), Ghaziabad 201002, India
| | - Rashmi Sharma
- Infectious Diseases Division, CSIR- Indian Institute of Integrative Medicine, Jammu 180001, India
- Academy of Scientific and Innovative Research (AcSIR), Ghaziabad 201002, India
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Fragment-Based Lead Discovery Strategies in Antimicrobial Drug Discovery. Antibiotics (Basel) 2023; 12:antibiotics12020315. [PMID: 36830226 PMCID: PMC9951956 DOI: 10.3390/antibiotics12020315] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2023] [Revised: 01/30/2023] [Accepted: 01/31/2023] [Indexed: 02/05/2023] Open
Abstract
Fragment-based lead discovery (FBLD) is a powerful application for developing ligands as modulators of disease targets. This approach strategy involves identification of interactions between low-molecular weight compounds (100-300 Da) and their putative targets, often with low affinity (KD ~0.1-1 mM) interactions. The focus of this screening methodology is to optimize and streamline identification of fragments with higher ligand efficiency (LE) than typical high-throughput screening. The focus of this review is on the last half decade of fragment-based drug discovery strategies that have been used for antimicrobial drug discovery.
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Togre NS, Vargas AM, Bhargavi G, Mallakuntla MK, Tiwari S. Fragment-Based Drug Discovery against Mycobacteria: The Success and Challenges. Int J Mol Sci 2022; 23:ijms231810669. [PMID: 36142582 PMCID: PMC9500838 DOI: 10.3390/ijms231810669] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2022] [Revised: 09/10/2022] [Accepted: 09/10/2022] [Indexed: 11/29/2022] Open
Abstract
The emergence of drug-resistant mycobacteria, including Mycobacterium tuberculosis (Mtb) and non-tuberculous mycobacteria (NTM), poses an increasing global threat that urgently demands the development of new potent anti-mycobacterial drugs. One of the approaches toward the identification of new drugs is fragment-based drug discovery (FBDD), which is the most ingenious among other drug discovery models, such as structure-based drug design (SBDD) and high-throughput screening. Specialized techniques, such as X-ray crystallography, nuclear magnetic resonance spectroscopy, and many others, are part of the drug discovery approach to combat the Mtb and NTM global menaces. Moreover, the primary drawbacks of traditional methods, such as the limited measurement of biomolecular toxicity and uncertain bioavailability evaluation, are successfully overcome by the FBDD approach. The current review focuses on the recognition of fragment-based drug discovery as a popular approach using virtual, computational, and biophysical methods to identify potent fragment molecules. FBDD focuses on designing optimal inhibitors against potential therapeutic targets of NTM and Mtb (PurC, ArgB, MmpL3, and TrmD). Additionally, we have elaborated on the challenges associated with the FBDD approach in the identification and development of novel compounds. Insights into the applications and overcoming the challenges of FBDD approaches will aid in the identification of potential therapeutic compounds to treat drug-sensitive and drug-resistant NTMs and Mtb infections.
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Knejzlík Z, Doležal M, Herkommerová K, Clarova K, Klíma M, Dedola M, Zborníková E, Rejman D, Pichová I. The mycobacterial guaB1 gene encodes a guanosine 5'-monophosphate reductase with a cystathionine-β-synthase domain. FEBS J 2022; 289:5571-5598. [PMID: 35338694 PMCID: PMC9790621 DOI: 10.1111/febs.16448] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2021] [Revised: 02/11/2022] [Accepted: 03/24/2022] [Indexed: 12/30/2022]
Abstract
Mycobacteria express enzymes from both the de novo and purine-salvage pathways. However, the regulation of these processes and the roles of individual metabolic enzymes have not been sufficiently detailed. Both Mycobacterium tuberculosis (Mtb) and Mycobacterium smegmatis (Msm) possess three guaB genes, but information is only available on guaB2, which encodes an essential inosine 5'-monophosphate dehydrogenase (IMPDH) involved in de novo purine biosynthesis. This study shows that guaB1, annotated in databases as a putative IMPDH, encodes a guanosine 5'-monophosphate reductase (GMPR), which recycles guanosine monophosphate to inosine monophosphate within the purine-salvage pathway and contains a cystathionine-β-synthase domain (CBS), which is essential for enzyme activity. GMPR activity is allosterically regulated by the ATP/GTP ratio in a pH-dependent manner. Bioinformatic analysis has indicated the presence of GMPRs containing CBS domains across the entire Actinobacteria phylum.
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Affiliation(s)
- Zdeněk Knejzlík
- Institute of Organic Chemistry and Biochemistry of the Czech Academy of SciencesPragueCzech Republic
| | - Michal Doležal
- Institute of Organic Chemistry and Biochemistry of the Czech Academy of SciencesPragueCzech Republic
| | - Klára Herkommerová
- Institute of Organic Chemistry and Biochemistry of the Czech Academy of SciencesPragueCzech Republic
| | - Kamila Clarova
- Institute of Organic Chemistry and Biochemistry of the Czech Academy of SciencesPragueCzech Republic
| | - Martin Klíma
- Institute of Organic Chemistry and Biochemistry of the Czech Academy of SciencesPragueCzech Republic
| | - Matteo Dedola
- Institute of Organic Chemistry and Biochemistry of the Czech Academy of SciencesPragueCzech Republic
| | - Eva Zborníková
- Institute of Organic Chemistry and Biochemistry of the Czech Academy of SciencesPragueCzech Republic
| | - Dominik Rejman
- Institute of Organic Chemistry and Biochemistry of the Czech Academy of SciencesPragueCzech Republic
| | - Iva Pichová
- Institute of Organic Chemistry and Biochemistry of the Czech Academy of SciencesPragueCzech Republic
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5
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Pepi MJ, Chacko S, Marqus GM, Singh V, Wang Z, Planck K, Cullinane RT, Meka PN, Gollapalli DR, Ioerger TR, Rhee KY, Cuny GD, Boshoff HI, Hedstrom L. A d-Phenylalanine-Benzoxazole Derivative Reveals the Role of the Essential Enzyme Rv3603c in the Pantothenate Biosynthetic Pathway of Mycobacterium tuberculosis. ACS Infect Dis 2022; 8:330-342. [PMID: 35015509 DOI: 10.1021/acsinfecdis.1c00461] [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: 11/28/2022]
Abstract
New drugs and new targets are urgently needed to treat tuberculosis. We discovered that d-phenylalanine-benzoxazole Q112 displays potent antibacterial activity against Mycobacterium tuberculosis (Mtb) in multiple media and in macrophage infections. A metabolomic profiling indicates that Q112 has a unique mechanism of action. Q112 perturbs the essential pantothenate/coenzyme A biosynthetic pathway, depleting pantoate while increasing ketopantoate, as would be expected if ketopantoate reductase (KPR) were inhibited. We searched for alternative KPRs, since the enzyme annotated as PanE KPR is not essential in Mtb. The ketol-acid reductoisomerase IlvC catalyzes the KPR reaction in the close Mtb relative Corynebacterium glutamicum, but Mtb IlvC does not display KPR activity. We identified the essential protein Rv3603c as an orthologue of PanG KPR and demonstrated that a purified recombinant Rv3603c has KPR activity. Q112 inhibits Rv3603c, explaining the metabolomic changes. Surprisingly, pantothenate does not rescue Q112-treated bacteria, indicating that Q112 has an additional target(s). Q112-resistant strains contain loss-of-function mutations in the twin arginine translocase TatABC, further underscoring Q112's unique mechanism of action. Loss of TatABC causes a severe fitness deficit attributed to changes in nutrient uptake, suggesting that Q112 resistance may derive from a decrease in uptake.
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Affiliation(s)
- Michael J. Pepi
- Graduate Program in Chemistry, Brandeis University, Waltham 02453, Massachusetts, United States
| | - Shibin Chacko
- Department of Biology, Brandeis University, Waltham 02453, Massachusetts, United States
| | - Gary M. Marqus
- Graduate Program in Chemistry, Brandeis University, Waltham 02453, Massachusetts, United States
| | - Vinayak Singh
- Drug Discovery and Development Centre (H3D), and South African Medical Research Council Drug Discovery and Development Research Unit, Department of Chemistry and Institute of Infectious Disease and Molecular Medicine, University of Cape Town, Rondebosch 7701, South Africa
| | - Zhe Wang
- Division of Infectious Diseases, Weill Department of Medicine, Weill Cornell Medical College, New York 10065, New York, United States
| | - Kyle Planck
- Division of Infectious Diseases, Weill Department of Medicine, Weill Cornell Medical College, New York 10065, New York, United States
| | - Ryan T. Cullinane
- Department of Biology, Brandeis University, Waltham 02453, Massachusetts, United States
| | - Penchala N. Meka
- Department of Biology, Brandeis University, Waltham 02453, Massachusetts, United States
| | | | - Thomas R. Ioerger
- Department of Computer Science and Engineering, Texas A&M University, College Station 77843, Texas, United States
| | - Kyu Y. Rhee
- Division of Infectious Diseases, Weill Department of Medicine, Weill Cornell Medical College, New York 10065, New York, United States
| | - Gregory D. Cuny
- Department of Pharmacological and Pharmaceutical Sciences, College of Pharmacy, University of Houston, Houston 77204, Texas, United States
| | - Helena I.M. Boshoff
- Tuberculosis Research Section, National Institute of Allergy and Infectious Diseases, Bethesda 20892, Maryland, United States
| | - Lizbeth Hedstrom
- Department of Biology, Brandeis University, Waltham 02453, Massachusetts, United States
- Department of Chemistry, Brandeis University, Waltham 02453, Massachusetts, United States
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6
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Recent advancements and developments in search of anti-tuberculosis agents: A quinquennial update and future directions. J Mol Struct 2022. [DOI: 10.1016/j.molstruc.2021.131473] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
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7
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Song L, Merceron R, Hulpia F, Lucía A, Gracia B, Jian Y, Risseeuw MDP, Verstraelen T, Cos P, Aínsa JA, Boshoff HI, Munier-Lehmann H, Savvides SN, Van Calenbergh S. Structure-aided optimization of non-nucleoside M. tuberculosis thymidylate kinase inhibitors. Eur J Med Chem 2021; 225:113784. [PMID: 34450493 PMCID: PMC10500704 DOI: 10.1016/j.ejmech.2021.113784] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2021] [Revised: 08/14/2021] [Accepted: 08/14/2021] [Indexed: 10/20/2022]
Abstract
Mycobacterium tuberculosis thymidylate kinase (MtTMPK) has emerged as an attractive target for rational drug design. We recently investigated new families of non-nucleoside MtTMPK inhibitors in an effort to diversify MtTMPK inhibitor chemical space. We here report a new series of MtTMPK inhibitors by combining the Topliss scheme with rational drug design approaches, fueled by two co-crystal structures of MtTMPK in complex with developed inhibitors. These efforts furnished the most potent MtTMPK inhibitors in our assay, with two analogues displaying low micromolar MIC values against H37Rv Mtb. Prepared inhibitors address new sub-sites in the MtTMPK nucleotide binding pocket, thereby offering new insights into its druggability. We studied the role of efflux pumps as well as the impact of cell wall permeabilizers for selected compounds to potentially provide an explanation for the lack of correlation between potent enzyme inhibition and whole-cell activity.
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Affiliation(s)
- Lijun Song
- Laboratory for Medicinal Chemistry (FFW), Ghent University, Tergestensis 460, B-9000, Gent, Belgium; 3M, Zwijndrecht, Belgium
| | - Romain Merceron
- VIB Center for Inflammation Research, Zwijnaarde, Ghent, 9052, Belgium; Department of Biochemistry and Microbiology, Ghent University, Technologiepark 927, 9052, Zwijnaarde, Ghent, Belgium; Eurofins Group, Poitiers, France
| | - Fabian Hulpia
- Laboratory for Medicinal Chemistry (FFW), Ghent University, Tergestensis 460, B-9000, Gent, Belgium; Janssen Pharmaceutica, Beerse, Belgium
| | - Ainhoa Lucía
- Grupo de Genética de Micobacterias, Departamento de Microbiología, Facultad de Medicina, and BIFI, Universidad de Zaragoza, Zaragoza, Spain; CIBER Enfermedades Respiratorias (CIBERES), Instituto de Salud Carlos III, 28029, Madrid, Spain
| | - Begoña Gracia
- Grupo de Genética de Micobacterias, Departamento de Microbiología, Facultad de Medicina, and BIFI, Universidad de Zaragoza, Zaragoza, Spain; CIBER Enfermedades Respiratorias (CIBERES), Instituto de Salud Carlos III, 28029, Madrid, Spain
| | - Yanlin Jian
- Laboratory for Medicinal Chemistry (FFW), Ghent University, Tergestensis 460, B-9000, Gent, Belgium
| | - Martijn D P Risseeuw
- Laboratory for Medicinal Chemistry (FFW), Ghent University, Tergestensis 460, B-9000, Gent, Belgium
| | - Toon Verstraelen
- Center for Melecular Modeling, Ghent University, Zwijnaarde, Ghent, 9052, Belgium
| | - Paul Cos
- Laboratory for Microbiology, Parasitology and Hygiene (LMPH), Department of Pharmaceutical Sciences, University of Antwerp, Campus Drie Eiken, Universiteitsplein 1, B-2610, Antwerpen, Belgium
| | - José A Aínsa
- Grupo de Genética de Micobacterias, Departamento de Microbiología, Facultad de Medicina, and BIFI, Universidad de Zaragoza, Zaragoza, Spain; CIBER Enfermedades Respiratorias (CIBERES), Instituto de Salud Carlos III, 28029, Madrid, Spain
| | - Helena I Boshoff
- Tuberculosis Research Section, Laboratory of Clinical Immunology and Microbiology, National Institute of Allergy and Infectious Disease, National Institutes of Health, 9000 Rockville Pike, Bethesda, MD, 20892, United States
| | - Hélène Munier-Lehmann
- CNRS UMR3523, Department of Structural Biology and Chemistry, Institut Pasteur, 75724, Paris Cedex 15, France
| | - Savvas N Savvides
- VIB Center for Inflammation Research, Zwijnaarde, Ghent, 9052, Belgium; Department of Biochemistry and Microbiology, Ghent University, Technologiepark 927, 9052, Zwijnaarde, Ghent, Belgium
| | - Serge Van Calenbergh
- Laboratory for Medicinal Chemistry (FFW), Ghent University, Tergestensis 460, B-9000, Gent, Belgium.
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Modi G, Marqus GM, Vippila MR, Gollapalli DR, Kim Y, Manna AC, Chacko S, Maltseva N, Wang X, Cullinane RT, Zhang Y, Kotler JLM, Kuzmic P, Zhang M, Lawson AP, Joachimiak A, Cheung A, Snider BB, Rothstein DM, Cuny GD, Hedstrom L. The Enzymatic Activity of Inosine 5'-Monophosphate Dehydrogenase May Not Be a Vulnerable Target for Staphylococcus aureus Infections. ACS Infect Dis 2021; 7:3062-3076. [PMID: 34590817 DOI: 10.1021/acsinfecdis.1c00342] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Many bacterial pathogens, including Staphylococcus aureus, require inosine 5'-monophosphate dehydrogenase (IMPDH) for infection, making this enzyme a promising new target for antibiotics. Although potent selective inhibitors of bacterial IMPDHs have been reported, relatively few have displayed antibacterial activity. Here we use structure-informed design to obtain inhibitors of S. aureus IMPDH (SaIMPDH) that have potent antibacterial activity (minimal inhibitory concentrations less than 2 μM) and low cytotoxicity in mammalian cells. The physicochemical properties of the most active compounds were within typical Lipinski/Veber space, suggesting that polarity is not a general requirement for achieving antibacterial activity. Five compounds failed to display activity in mouse models of septicemia and abscess infection. Inhibitor-resistant S. aureus strains readily emerged in vitro. Resistance resulted from substitutions in the cofactor/inhibitor binding site of SaIMPDH, confirming on-target antibacterial activity. These mutations decreased the binding of all inhibitors tested, but also decreased catalytic activity. Nonetheless, the resistant strains had comparable virulence to wild-type bacteria. Surprisingly, strains expressing catalytically inactive SaIMPDH displayed only a mild virulence defect. Collectively these observations question the vulnerability of the enzymatic activity of SaIMPDH as a target for the treatment of S. aureus infections, suggesting other functions of this protein may be responsible for its role in infection.
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Affiliation(s)
- Gyan Modi
- Department of Biology, Brandeis University, Waltham, Massachusetts 02453, United States
| | - Gary M. Marqus
- Graduate Program in Chemistry, Brandeis University, Waltham Massachusetts 02453, United States
| | - Mohana Rao Vippila
- Department of Pharmacological and Pharmaceutical Sciences, College of Pharmacy, University of Houston, Health Building 2, 4849 Calhoun Rd., Houston, Texas 77204, United States
| | | | - Youngchang Kim
- Center for Structural Genomics of Infectious Diseases, Consortium for Advanced Science and Engineering, University of Chicago, Chicago, Illinois 60667, United States
- The Structural Biology Center, X-ray Science Division, Argonne National Laboratory, Lemont, Illinois 60439, United States
| | - Adhar C. Manna
- Department of Microbiology and Immunology, Geisel School of Medicine at Dartmouth, Hanover, New Hampshire 03755, United States
| | - Shibin Chacko
- Department of Biology, Brandeis University, Waltham, Massachusetts 02453, United States
| | - Natalia Maltseva
- Center for Structural Genomics of Infectious Diseases, Consortium for Advanced Science and Engineering, University of Chicago, Chicago, Illinois 60667, United States
- The Structural Biology Center, X-ray Science Division, Argonne National Laboratory, Lemont, Illinois 60439, United States
| | - Xingyou Wang
- Graduate Program in Chemistry, Brandeis University, Waltham Massachusetts 02453, United States
| | - Ryan T. Cullinane
- Department of Biochemistry, Brandeis University, Massachusetts 02453, United States
| | - Yubo Zhang
- Department of Biochemistry, Brandeis University, Massachusetts 02453, United States
| | - Judy L. M. Kotler
- Graduate Program in Biochemistry and Biophysics, Brandeis University, Waltham, Massachusetts 02453, United States
| | - Petr Kuzmic
- BioKin Ltd., Watertown, Massachusetts 02472, United States
| | - Minjia Zhang
- Department of Biology, Brandeis University, Waltham, Massachusetts 02453, United States
| | - Ann P. Lawson
- Department of Biology, Brandeis University, Waltham, Massachusetts 02453, United States
| | - Andrzej Joachimiak
- Center for Structural Genomics of Infectious Diseases, Consortium for Advanced Science and Engineering, University of Chicago, Chicago, Illinois 60667, United States
- The Structural Biology Center, X-ray Science Division, Argonne National Laboratory, Lemont, Illinois 60439, United States
- Department of Biochemistry and Molecular Biology, University of Chicago, Chicago, Illinois 60367, United States
| | - Ambrose Cheung
- Department of Microbiology and Immunology, Geisel School of Medicine at Dartmouth, Hanover, New Hampshire 03755, United States
| | - Barry B. Snider
- Department of Chemistry, Brandeis University, Waltham, Massachusetts 02453, United States
| | - David M. Rothstein
- David Rothstein Consulting, LLC, Lexington, Massachusetts 02421, United States
| | - Gregory D. Cuny
- Department of Pharmacological and Pharmaceutical Sciences, College of Pharmacy, University of Houston, Health Building 2, 4849 Calhoun Rd., Houston, Texas 77204, United States
| | - Lizbeth Hedstrom
- Department of Biology, Brandeis University, Waltham, Massachusetts 02453, United States
- Department of Chemistry, Brandeis University, Waltham, Massachusetts 02453, United States
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Oh S, Trifonov L, Yadav VD, Barry CE, Boshoff HI. Tuberculosis Drug Discovery: A Decade of Hit Assessment for Defined Targets. Front Cell Infect Microbiol 2021; 11:611304. [PMID: 33791235 PMCID: PMC8005628 DOI: 10.3389/fcimb.2021.611304] [Citation(s) in RCA: 30] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2020] [Accepted: 02/25/2021] [Indexed: 11/20/2022] Open
Abstract
More than two decades have elapsed since the publication of the first genome sequence of Mycobacterium tuberculosis (Mtb) which, shortly thereafter, enabled methods to determine gene essentiality in the pathogen. Despite this, target-based approaches have not yielded drugs that have progressed to clinical testing. Whole-cell screening followed by elucidation of mechanism of action has to date been the most fruitful approach to progressing inhibitors into the tuberculosis drug discovery pipeline although target-based approaches are gaining momentum. This review discusses scaffolds that have been identified over the last decade from screens of small molecule libraries against Mtb or defined targets where mechanism of action investigation has defined target-hit couples and structure-activity relationship studies have described the pharmacophore.
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Affiliation(s)
- Sangmi Oh
- Tuberculosis Research Section, Laboratory of Clinical Immunology and Microbiology, National Institute of Allergy and Infectious Diseases (NIAID), National Institutes of Health (NIH), Bethesda, MD, United States
| | - Lena Trifonov
- Tuberculosis Research Section, Laboratory of Clinical Immunology and Microbiology, National Institute of Allergy and Infectious Diseases (NIAID), National Institutes of Health (NIH), Bethesda, MD, United States
| | - Veena D Yadav
- Tuberculosis Research Section, Laboratory of Clinical Immunology and Microbiology, National Institute of Allergy and Infectious Diseases (NIAID), National Institutes of Health (NIH), Bethesda, MD, United States
| | - Clifton E Barry
- Tuberculosis Research Section, Laboratory of Clinical Immunology and Microbiology, National Institute of Allergy and Infectious Diseases (NIAID), National Institutes of Health (NIH), Bethesda, MD, United States
| | - Helena I Boshoff
- Tuberculosis Research Section, Laboratory of Clinical Immunology and Microbiology, National Institute of Allergy and Infectious Diseases (NIAID), National Institutes of Health (NIH), Bethesda, MD, United States
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10
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Targeting NAD-dependent dehydrogenases in drug discovery against infectious diseases and cancer. Biochem Soc Trans 2021; 48:693-707. [PMID: 32311017 DOI: 10.1042/bst20191261] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2019] [Revised: 03/10/2020] [Accepted: 03/16/2020] [Indexed: 12/24/2022]
Abstract
Dehydrogenases are oxidoreductase enzymes that play a variety of fundamental functions in the living organisms and have primary roles in pathogen survival and infection processes as well as in cancer development. We review here a sub-set of NAD-dependent dehydrogenases involved in human diseases and the recent advancements in drug development targeting pathogen-associated NAD-dependent dehydrogenases. We focus also on the molecular aspects of the inhibition process listing the structures of the most relevant molecules targeting this enzyme family. Our aim is to review the most impacting findings regarding the discovery of novel inhibitory compounds targeting the selected NAD-dependent dehydrogenases involved in cancer and infectious diseases.
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11
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Jian Y, Forbes HE, Hulpia F, Risseeuw MDP, Caljon G, Munier-Lehmann H, Boshoff HIM, Van Calenbergh S. 2-((3,5-Dinitrobenzyl)thio)quinazolinones: Potent Antimycobacterial Agents Activated by Deazaflavin (F 420)-Dependent Nitroreductase (Ddn). J Med Chem 2021; 64:440-457. [PMID: 33347317 PMCID: PMC10629625 DOI: 10.1021/acs.jmedchem.0c01374] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Swapping the substituents in positions 2 and 4 of the previously synthesized but yet undisclosed 5-cyano-4-(methylthio)-2-arylpyrimidin-6-ones 4, ring closure, and further optimization led to the identification of the potent antitubercular 2-thio-substituted quinazolinone 26. Structure-activity relationship (SAR) studies indicated a crucial role for both meta-nitro substituents for antitubercular activity, while the introduction of polar substituents on the quinazolinone core allowed reduction of bovine serum albumin (BSA) binding (63c, 63d). While most of the tested quinazolinones exhibited no cytotoxicity against MRC-5, the most potent compound 26 was found to be mutagenic via the Ames test. This analogue exhibited moderate inhibitory potency against Mycobacterium tuberculosis thymidylate kinase, the target of the 3-cyanopyridones that lies at the basis of the current analogues, indicating that the whole-cell antimycobacterial activity of the present S-substituted thioquinazolinones is likely due to modulation of alternative or additional targets. Diminished antimycobacterial activity was observed against mutants affected in cofactor F420 biosynthesis (fbiC), cofactor reduction (fgd), or deazaflavin-dependent nitroreductase activity (rv3547), indicating that reductive activation of the 3,5-dinitrobenzyl analogues is key to antimycobacterial activity.
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Affiliation(s)
- Yanlin Jian
- Laboratory for Medicinal Chemistry (FFW), Ghent University, Ottergemsesteenweg 460, B-9000 Gent, Belgium
| | - He Eun Forbes
- Tuberculosis Research Section, Laboratory of Clinical Immunology and Microbiology, National Institute of Allergy and Infectious Disease, National Institutes of Health, 9000 Rockville Pike, Bethesda, Maryland 20892, United States
| | - Fabian Hulpia
- Laboratory for Medicinal Chemistry (FFW), Ghent University, Ottergemsesteenweg 460, B-9000 Gent, Belgium
| | - Martijn D. P. Risseeuw
- Laboratory for Medicinal Chemistry (FFW), Ghent University, Ottergemsesteenweg 460, B-9000 Gent, Belgium
| | - Guy Caljon
- Laboratory of Microbiology, Parasitology and Hygiene, University of Antwerp, Universiteitsplein 1 (S7), B-2610 Wilrijk, Belgium
| | - Hélène Munier-Lehmann
- Unit of Chemistry and Biocatalysis, Department of Structural Biology and Chemistry, Institut Pasteur, CNRS UMR3523, 28 Rue du Dr. Roux, Cedex 15 75724 Paris, France
| | - Helena I. M. Boshoff
- Tuberculosis Research Section, Laboratory of Clinical Immunology and Microbiology, National Institute of Allergy and Infectious Disease, National Institutes of Health, 9000 Rockville Pike, Bethesda, Maryland 20892, United States
| | - Serge Van Calenbergh
- Laboratory for Medicinal Chemistry (FFW), Ghent University, Ottergemsesteenweg 460, B-9000 Gent, Belgium
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12
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Lee S, Ku AF, Vippila MR, Wang Y, Zhang M, Wang X, Hedstrom L, Cuny GD. Mycophenolic anilides as broad specificity inosine-5'-monophosphate dehydrogenase (IMPDH) inhibitors. Bioorg Med Chem Lett 2020; 30:127543. [PMID: 32931912 DOI: 10.1016/j.bmcl.2020.127543] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2020] [Revised: 09/03/2020] [Accepted: 09/04/2020] [Indexed: 11/28/2022]
Abstract
Inosine-5'-monophosphate dehydrogenase (IMPDH) is a potential target for microorganisms. However, identifying inhibitor design determinants for IMPDH orthologs continues to evolve. Herein, a series of mycophenolic anilide inhibitors of Cryptosporidium parvum and human IMPDHs are reported. Furthermore, molecular docking of 12 (e.g. SH-19; CpIMPDH Ki,app = 0.042 ± 0.015 µM, HsIMPDH2 Ki,app = 0.13 ± 0.05 µM) supports different binding modes with the two enzymes. For CpIMPDH the inhibitor extends into a pocket in an adjacent subunit. In contrast, docking suggests the inhibitor interacts with Ser276 in the NAD binding site in HsIMPDH2, as well as an adjacent pocket within the same subunit. These results provide further guidance for generating IMPDH inhibitors for enzymes found in an array of pathogenic microorganisms, including Mycobacterium tuberculosis.
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Affiliation(s)
- Seungheon Lee
- Department of Pharmacological and Pharmaceutical Sciences, University of Houston, Health Building 2, Houston, TX 77204, USA
| | - Angela F Ku
- Department of Pharmacological and Pharmaceutical Sciences, University of Houston, Health Building 2, Houston, TX 77204, USA; Department of Chemistry, University of Houston, Health Building 2, Houston, TX 77204, USA
| | - Mohana Rao Vippila
- Department of Pharmacological and Pharmaceutical Sciences, University of Houston, Health Building 2, Houston, TX 77204, USA
| | - Yong Wang
- Department of Pharmacological and Pharmaceutical Sciences, University of Houston, Health Building 2, Houston, TX 77204, USA
| | - Minjia Zhang
- Departments of Biology, 415 South St., Waltham, MA 02454, USA
| | - Xingyou Wang
- Departments of Biology, 415 South St., Waltham, MA 02454, USA
| | - Lizbeth Hedstrom
- Departments of Biology, 415 South St., Waltham, MA 02454, USA; Chemistry, Brandeis University, 415 South St., Waltham, MA 02454, USA
| | - Gregory D Cuny
- Department of Pharmacological and Pharmaceutical Sciences, University of Houston, Health Building 2, Houston, TX 77204, USA.
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13
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Jian Y, Merceron R, De Munck S, Forbes HE, Hulpia F, Risseeuw MDP, Van Hecke K, Savvides SN, Munier-Lehmann H, Boshoff HIM, Van Calenbergh S. Endeavors towards transformation of M. tuberculosis thymidylate kinase (MtbTMPK) inhibitors into potential antimycobacterial agents. Eur J Med Chem 2020; 206:112659. [PMID: 32823003 PMCID: PMC11000207 DOI: 10.1016/j.ejmech.2020.112659] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2020] [Revised: 07/08/2020] [Accepted: 07/08/2020] [Indexed: 01/30/2023]
Abstract
As the last enzyme in nucleotide synthesis as precursors for DNA replication, thymidylate kinase of M. tuberculosis (MtbTMPK) attracts significant interest as a target in the discovery of new anti-tuberculosis agents. Earlier, we discovered potent MtbTMPK inhibitors, but these generally suffered from poor antimycobacterial activity, which we hypothesize is due to poor bacterial uptake. To address this, we herein describe our efforts to equip previously reported MtbTMPK inhibitors with targeting moieties to increase the whole cell activity of the hybrid analogues. Introduction of a simplified Fe-chelating siderophore motif gave rise to analogue 17 that combined favorable enzyme inhibitory activity with significant activity against M. tuberculosis (MIC of 12.5 μM). Conjugation of MtbTMPK inhibitors with an imidazo[1,2-a]pyridine or 3,5-dinitrobenzamide scaffold afforded analogues 26, 27 and 28, with moderate MtbTMPK enzyme inhibitory potency, but sub-micromolar activity against mycobacteria without significant cytotoxicity. These results indicate that conjugation with structural motifs known to favor mycobacterial uptake may be a valid approach for discovering new antimycobacterial agents.
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Affiliation(s)
- Yanlin Jian
- Laboratory for Medicinal Chemistry (FFW), Ghent University, Ottergemsesteenweg 460, B-9000, Ghent, Belgium
| | - Romain Merceron
- VIB Center for Inflammation Research, Zwijnaarde, Ghent, 9052, Belgium; Department of Biochemistry and Microbiology, Ghent University, Ghent, 9052, Belgium
| | - Steven De Munck
- VIB Center for Inflammation Research, Zwijnaarde, Ghent, 9052, Belgium; Department of Biochemistry and Microbiology, Ghent University, Ghent, 9052, Belgium
| | - He Eun Forbes
- Tuberculosis Research Section, Laboratory of Clinical Immunology and Microbiology, National Institute of Allergy and Infectious Disease, National Institutes of Health, 9000 Rockville Pike, Bethesda, MD, 20892, United States
| | - Fabian Hulpia
- Laboratory for Medicinal Chemistry (FFW), Ghent University, Ottergemsesteenweg 460, B-9000, Ghent, Belgium
| | - Martijn D P Risseeuw
- Laboratory for Medicinal Chemistry (FFW), Ghent University, Ottergemsesteenweg 460, B-9000, Ghent, Belgium
| | - Kristof Van Hecke
- XStruct, Department of Chemistry, Ghent University, Krijgslaan 281 S3, Gent, B-9000, Belgium
| | - Savvas N Savvides
- VIB Center for Inflammation Research, Zwijnaarde, Ghent, 9052, Belgium; Department of Biochemistry and Microbiology, Ghent University, Ghent, 9052, Belgium
| | - Hélène Munier-Lehmann
- Unit of Chemistry and Biocatalysis, Department of Structural Biology and Chemistry, Institut Pasteur, CNRS UMR3523, 28 Rue du Dr. Roux, Cedex, 15 75724, Paris, France
| | - Helena I M Boshoff
- Tuberculosis Research Section, Laboratory of Clinical Immunology and Microbiology, National Institute of Allergy and Infectious Disease, National Institutes of Health, 9000 Rockville Pike, Bethesda, MD, 20892, United States
| | - Serge Van Calenbergh
- Laboratory for Medicinal Chemistry (FFW), Ghent University, Ottergemsesteenweg 460, B-9000, Ghent, Belgium.
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14
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Adedeji AA, Babalola OO. Secondary metabolites as plant defensive strategy: a large role for small molecules in the near root region. PLANTA 2020; 252:61. [PMID: 32965531 DOI: 10.1007/s00425-020-03468-1] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/11/2020] [Accepted: 09/12/2020] [Indexed: 05/20/2023]
Abstract
The roles of plant roots are not merely limited to the provision of mechanical support, nutrients and water, but also include more specific roles, such as the capacity to secrete diverse chemical substances. These metabolites are actively secreted in the near root and play specific and significant functions in plant defense and communication. In this review, we detail the various preventive roles of these powerful substances in the rhizosphere with a perspective as to how plants recruit microbes as a preventive measure against other pathogenic microbes, also, briefly about how the rhizosphere can repel insect pests, and how these chemical substances alter microbial dynamics and enhance symbiotic relationships. We also highlight the need for more research in this area to detail the mode of action and quantification of these compounds in the environment and their roles in some important biological processes in microorganisms and plants.
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Affiliation(s)
- Atilade Adedayo Adedeji
- Food Security and Safety Niche Area, Faculty of Natural and Agricultural Sciences, North-West University, Private Bag X2046, Mmabatho, 2735, South Africa
- Department of Biochemistry and Microbiology, School of Environmental and Biological Sciences, Rutgers University, New Brunswick, NJ, USA
| | - Olubukola Oluranti Babalola
- Food Security and Safety Niche Area, Faculty of Natural and Agricultural Sciences, North-West University, Private Bag X2046, Mmabatho, 2735, South Africa.
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15
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Jian Y, Hulpia F, Risseeuw MDP, Forbes HE, Munier-Lehmann H, Caljon G, Boshoff HIM, Van Calenbergh S. Synthesis and structure activity relationships of cyanopyridone based anti-tuberculosis agents. Eur J Med Chem 2020; 201:112450. [PMID: 32623208 DOI: 10.1016/j.ejmech.2020.112450] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2020] [Revised: 05/08/2020] [Accepted: 05/10/2020] [Indexed: 11/15/2022]
Abstract
Mycobacterium tuberculosis, the causative agent of tuberculosis, relies on thymidylate kinase (MtbTMPK) for the synthesis of thymidine triphosphates and thus also DNA synthesis. Therefore, this enzyme constitutes a potential Achilles heel of the pathogen. Based on a previously reported MtbTMPK 6-aryl-substituted pyridone inhibitor and guided by two co-crystal structures of MtbTMPK with pyridone- and thymine-based inhibitors, we report the synthesis of a series of aryl-shifted cyanopyridone analogues. These compounds generally lacked significant MtbTMPK inhibitory potency, but some analogues did exhibit promising antitubercular activity. Analogue 11i demonstrated a 10-fold increased antitubercular activity (MIC H37Rv, 1.2 μM) compared to literature compound 5. Many analogues with whole-cell antimycobacterial activity were devoid of significant cytotoxicity.
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Affiliation(s)
- Yanlin Jian
- Laboratory for Medicinal Chemistry (FFW), Ghent University, Ottergemsesteenweg 460, B9000, Gent, Belgium
| | - Fabian Hulpia
- Laboratory for Medicinal Chemistry (FFW), Ghent University, Ottergemsesteenweg 460, B9000, Gent, Belgium
| | - Martijn D P Risseeuw
- Laboratory for Medicinal Chemistry (FFW), Ghent University, Ottergemsesteenweg 460, B9000, Gent, Belgium
| | - He Eun Forbes
- Tuberculosis Research Section, Laboratory of Clinical Immunology and Microbiology, National Institute of Allergy and Infectious Disease, National Institutes of Health, 9000 Rockville Pike, Bethesda, MD, 20892, United States
| | - Hélène Munier-Lehmann
- Unit of Chemistry and Biocatalysis, Department of Structural Biology and Chemistry, Institut Pasteur, CNRS UMR3523, 28 Rue du Dr. Roux, Cedex 15, 75724, Paris, France
| | - Guy Caljon
- Laboratory of Microbiology, Parasitology and Hygiene, University of Antwerp, Universiteitsplein 1(S7), B2610, Wilrijk, Belgium
| | - Helena I M Boshoff
- Tuberculosis Research Section, Laboratory of Clinical Immunology and Microbiology, National Institute of Allergy and Infectious Disease, National Institutes of Health, 9000 Rockville Pike, Bethesda, MD, 20892, United States
| | - Serge Van Calenbergh
- Laboratory for Medicinal Chemistry (FFW), Ghent University, Ottergemsesteenweg 460, B9000, Gent, Belgium.
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16
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Nan J, Zhang S, Zhan P, Jiang L. Evaluation of Bronopol and Disulfiram as Potential Candidatus Liberibacter asiaticus Inosine 5'-Monophosphate Dehydrogenase Inhibitors by Using Molecular Docking and Enzyme Kinetic. Molecules 2020; 25:E2313. [PMID: 32423116 PMCID: PMC7287799 DOI: 10.3390/molecules25102313] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2020] [Revised: 04/30/2020] [Accepted: 05/11/2020] [Indexed: 12/12/2022] Open
Abstract
Citrus huanglongbing (HLB) is a destructive disease that causes significant damage to many citrus producing areas worldwide. To date, no strategy against this disease has been established. Inosine 5'-monophosphate dehydrogenase (IMPDH) plays crucial roles in the de novo synthesis of guanine nucleotides. This enzyme is used as a potential target to treat bacterial infection. In this study, the crystal structure of a deletion mutant of CLas IMPDHΔ98-201 in the apo form was determined. Eight known bioactive compounds were used as ligands for molecular docking. The results showed that bronopol and disulfiram bound to CLas IMPDHΔ98-201 with high affinity. These compounds were tested for their inhibition against CLas IMPDHΔ98-201 activity. Bronopol and disulfiram showed high inhibition at nanomolar concentrations, and bronopol was found to be the most potent molecule (Ki = 234 nM). The Ki value of disulfiram was 616 nM. These results suggest that bronopol and disulfiram can be considered potential candidate agents for the development of CLas inhibitors.
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Affiliation(s)
- Jing Nan
- College of Horticulture and Forestry, Key Laboratory of Horticultural Plant Biology of Ministry of Education, Huazhong Agricultural University, Wuhan 430070, China; (J.N.); (P.Z.)
| | - Shaoran Zhang
- State Key Laboratory of Agricultural Microbiology, Huazhong Agricultural University, Wuhan 430070, China;
| | - Ping Zhan
- College of Horticulture and Forestry, Key Laboratory of Horticultural Plant Biology of Ministry of Education, Huazhong Agricultural University, Wuhan 430070, China; (J.N.); (P.Z.)
| | - Ling Jiang
- College of Horticulture and Forestry, Key Laboratory of Horticultural Plant Biology of Ministry of Education, Huazhong Agricultural University, Wuhan 430070, China; (J.N.); (P.Z.)
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17
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Miggiano R, Morrone C, Rossi F, Rizzi M. Targeting Genome Integrity in Mycobacterium Tuberculosis: From Nucleotide Synthesis to DNA Replication and Repair. Molecules 2020; 25:E1205. [PMID: 32156001 PMCID: PMC7179400 DOI: 10.3390/molecules25051205] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2020] [Revised: 03/04/2020] [Accepted: 03/05/2020] [Indexed: 12/12/2022] Open
Abstract
Mycobacterium tuberculosis (MTB) is the causative agent of tuberculosis (TB), an ancient disease which still today causes 1.4 million deaths worldwide per year. Long-term, multi-agent anti-tubercular regimens can lead to the anticipated non-compliance of the patient and increased drug toxicity, which in turn can contribute to the emergence of drug-resistant MTB strains that are not susceptible to first- and second-line available drugs. Hence, there is an urgent need for innovative antitubercular drugs and vaccines. A number of biochemical processes are required to maintain the correct homeostasis of DNA metabolism in all organisms. Here we focused on reviewing our current knowledge and understanding of biochemical and structural aspects of relevance for drug discovery, for some such processes in MTB, and particularly DNA synthesis, synthesis of its nucleotide precursors, and processes that guarantee DNA integrity and genome stability. Overall, the area of drug discovery in DNA metabolism appears very much alive, rich of investigations and promising with respect to new antitubercular drug candidates. However, the complexity of molecular events that occur in DNA metabolic processes requires an accurate characterization of mechanistic details in order to avoid major flaws, and therefore the failure, of drug discovery approaches targeting genome integrity.
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Affiliation(s)
- Riccardo Miggiano
- Department of Pharmaceutical Sciences, University of Piemonte Orientale, Via Bovio 6, 28100 Novara, Italy; (C.M.); (F.R.)
| | | | | | - Menico Rizzi
- Department of Pharmaceutical Sciences, University of Piemonte Orientale, Via Bovio 6, 28100 Novara, Italy; (C.M.); (F.R.)
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18
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Hypoxanthine-Guanine Phosphoribosyltransferase Is Dispensable for Mycobacterium smegmatis Viability. J Bacteriol 2020; 202:JB.00710-19. [PMID: 31818925 DOI: 10.1128/jb.00710-19] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2019] [Accepted: 12/05/2019] [Indexed: 12/19/2022] Open
Abstract
Purine metabolism plays a ubiquitous role in the physiology of Mycobacterium tuberculosis and other mycobacteria. The purine salvage enzyme hypoxanthine-guanine phosphoribosyltransferase (HGPRT) is essential for M. tuberculosis growth in vitro; however, its precise role in M. tuberculosis physiology is unclear. Membrane-permeable prodrugs of specifically designed HGPRT inhibitors arrest the growth of M. tuberculosis and represent potential new antituberculosis compounds. Here, we investigated the purine salvage pathway in the model organism Mycobacterium smegmatis Using genomic deletion analysis, we confirmed that HGPRT is the only guanine and hypoxanthine salvage enzyme in M. smegmatis but is not required for in vitro growth of this mycobacterium or survival under long-term stationary-phase conditions. We also found that prodrugs of M. tuberculosis HGPRT inhibitors displayed an unexpected antimicrobial activity against M. smegmatis that is independent of HGPRT. Our data point to a different mode of mechanism of action for these inhibitors than was originally proposed.IMPORTANCE Purine bases, released by the hydrolytic and phosphorolytic degradation of nucleic acids and nucleotides, can be salvaged and recycled. The hypoxanthine-guanine phosphoribosyltransferase (HGPRT), which catalyzes the formation of guanosine-5'-monophosphate from guanine and inosine-5'-monophosphate from hypoxanthine, represents a potential target for specific inhibitor development. Deletion of the HGPRT gene (Δhgprt) in the model organism Mycobacterium smegmatis confirmed that this enzyme is not essential for M. smegmatis growth. Prodrugs of acyclic nucleoside phosphonates (ANPs), originally designed against HGPRT from Mycobacterium tuberculosis, displayed anti-M. smegmatis activities comparable to those obtained for M. tuberculosis but also inhibited the Δhgprt M. smegmatis strain. These results confirmed that ANPs act in M. smegmatis by a mechanism independent of HGPRT.
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19
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Johnson MC, Kollman JM. Cryo-EM structures demonstrate human IMPDH2 filament assembly tunes allosteric regulation. eLife 2020; 9:e53243. [PMID: 31999252 PMCID: PMC7018514 DOI: 10.7554/elife.53243] [Citation(s) in RCA: 43] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2019] [Accepted: 01/29/2020] [Indexed: 02/06/2023] Open
Abstract
Inosine monophosphate dehydrogenase (IMPDH) mediates the first committed step in guanine nucleotide biosynthesis and plays important roles in cellular proliferation and the immune response. IMPDH reversibly polymerizes in cells and tissues in response to changes in metabolic demand. Self-assembly of metabolic enzymes is increasingly recognized as a general mechanism for regulating activity, typically by stabilizing specific conformations of an enzyme, but the regulatory role of IMPDH filaments has remained unclear. Here, we report a series of human IMPDH2 cryo-EM structures in both active and inactive conformations. The structures define the mechanism of filament assembly, and reveal how filament-dependent allosteric regulation of IMPDH2 makes the enzyme less sensitive to feedback inhibition, explaining why assembly occurs under physiological conditions that require expansion of guanine nucleotide pools. Tuning sensitivity to an allosteric inhibitor distinguishes IMPDH from other metabolic filaments, and highlights the diversity of regulatory outcomes that can emerge from self-assembly.
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Affiliation(s)
- Matthew C Johnson
- Department of BiochemistryUniversity of WashingtonSeattleUnited States
| | - Justin M Kollman
- Department of BiochemistryUniversity of WashingtonSeattleUnited States
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20
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Juvale K, Shaik A, Kirubakaran S. Inhibitors of inosine 5'-monophosphate dehydrogenase as emerging new generation antimicrobial agents. MEDCHEMCOMM 2019; 10:1290-1301. [PMID: 31534651 PMCID: PMC6727467 DOI: 10.1039/c9md00179d] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/26/2019] [Accepted: 05/01/2019] [Indexed: 12/15/2022]
Abstract
Inosine 5'-monophosphate dehydrogenase (IMPDH) is a vital enzyme involved in the de novo synthesis of guanine nucleotides. IMPDH catalyzes a crucial step of converting IMP into XMP that is further converted into GMP. Microbial infections rely on the rapid proliferation of bacteria, and this requires the rate-limiting enzyme IMPDH to expand the guanine nucleotide pool and hence, IMPDH has recently received lots of attention as a potential target for treating infections. Owing to the structural and kinetic differences in the host IMPDH and bacterial IMPDH, a selective targeting is possible and is a crucial feature in the development of new potent and selective inhibitors of bacterial IMPDH. Earlier screening of small molecules revealed a structural requirement for the bacterial/protozoal IMPDH. Early optimization of benzimidazole and benzoxazole scaffolds led to the discovery of new potent and selective inhibitors of pathogenic IMPDH. Further research is vastly focused on the development of highly potent and selective inhibitors of various bacterial IMPDHs. Such studies reveal the importance of this excellent target for treating infectious diseases. The current review focuses on the recent developments in the discovery and development of selective inhibitors of bacterial/protozoal IMPDH with emphasis on the inhibition mechanism and structure-activity relationship.
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Affiliation(s)
- Kapil Juvale
- Shobhaben Pratapbhai Patel School of Pharmacy & Technology Management , SVKM's NMIMS , V.L. Mehta Road, Vile Parle (W) , Mumbai , 400056 India
| | - Althaf Shaik
- Chemistry , Indian Institute of Technology Gandhinagar , Palaj Village , Gandhinagar , 382355 India .
| | - Sivapriya Kirubakaran
- Chemistry , Indian Institute of Technology Gandhinagar , Palaj Village , Gandhinagar , 382355 India .
- Bio-engineering , Indian Institute of Technology Gandhinagar , Palaj Village , Gandhinagar , 382355 India
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21
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Jangra S, Purushothaman G, Juvale K, Ravi S, Menon A, Thiruvenkatam V, Kirubakaran S. Synthesis and In Vitro Enzymatic Studies of New 3-Aryldiazenyl Indoles as Promising Helicobacter pylori IMPDH Inhibitors. Curr Top Med Chem 2019; 19:376-382. [PMID: 30827248 DOI: 10.2174/1568026619666190227212334] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2018] [Revised: 01/30/2019] [Accepted: 02/09/2019] [Indexed: 11/22/2022]
Abstract
BACKGROUND & OBJECTIVE Helicobacter pylori infection is one of the primary causes of peptic ulcer followed by gastric cancer in the world population. Due to increased occurrences of multi-drug resistance to the currently available antibiotics, there is an urgent need for a new class of drugs against H. pylori. Inosine 5'-monophosphate dehydrogenase (IMPDH), a metabolic enzyme plays a significant role in cell proliferation and cell growth. It catalyses guanine nucleotide synthesis. IMPDH enzyme has been exploited as a target for antiviral, anticancer and immunosuppressive drugs. Recently, bacterial IMPDH has been studied as a potential target for treating bacterial infections. Differences in the structural and kinetic parameters of the eukaryotic and prokaryotic IMPDH make it possible to target bacterial enzyme selectively. METHODS In the current work, we have synthesised and studied the effect of substituted 3-aryldiazenyl indoles on Helicobacter pylori IMPDH (HpIMPDH) activity. The synthesised molecules were examined for their inhibitory potential against recombinant HpIMPDH. RESULTS In this study, compounds 1 and 2 were found to be the most potent inhibitors amongst the database with IC50 of 0.8 ± 0.02µM and 1 ± 0.03 µM, respectively. CONCLUSION When compared to the most potent known HpIMPDH inhibitor molecule C91, 1 was only four-fold less potent and can be a good lead for further development of selective and potent inhibitors of HpIMPDH.
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Affiliation(s)
- Sachin Jangra
- Chemistry, Indian Institute of Technology Gandhinagar, Gujarat, India
| | | | - Kapil Juvale
- Shobhaben Pratapbhai Patel School of Pharmacy & Technology Management, SVKM's NMIMS, V.L. Mehta Road, Vile Parle (W), Mumbai, India
| | - Srimadhavi Ravi
- Shobhaben Pratapbhai Patel School of Pharmacy & Technology Management, SVKM's NMIMS, V.L. Mehta Road, Vile Parle (W), Mumbai, India
| | - Aishwarya Menon
- Biological Engineering, Indian Institute of Technology Gandhinagar, Gujarat, India
| | - Vijay Thiruvenkatam
- Biological Engineering, Indian Institute of Technology Gandhinagar, Gujarat, India
| | - Sivapriya Kirubakaran
- Chemistry, Indian Institute of Technology Gandhinagar, Gujarat, India.,Biological Engineering, Indian Institute of Technology Gandhinagar, Gujarat, India
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22
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Design, synthesis and biological evaluation of Helicobacter pylori inosine 5′-monophosphate dehydrogenase (HpIMPDH) inhibitors. Further optimization of selectivity towards HpIMPDH over human IMPDH2. Bioorg Chem 2019; 87:753-764. [PMID: 30974298 DOI: 10.1016/j.bioorg.2019.04.001] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2018] [Revised: 03/20/2019] [Accepted: 04/01/2019] [Indexed: 02/05/2023]
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23
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Synthesis and Structure-Activity relationship of 1-(5-isoquinolinesulfonyl)piperazine analogues as inhibitors of Mycobacterium tuberculosis IMPDH. Eur J Med Chem 2019; 174:309-329. [PMID: 31055147 PMCID: PMC6990405 DOI: 10.1016/j.ejmech.2019.04.027] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2018] [Revised: 04/11/2019] [Accepted: 04/11/2019] [Indexed: 02/06/2023]
Abstract
Tuberculosis (TB) is a major infectious disease associated increasingly with drug resistance. Thus, new anti-tubercular agents with novel mechanisms of action are urgently required for the treatment of drug-resistant TB. In prior work, we identified compound 1 (cyclohexyl(4-(isoquinolin-5-ylsulfonyl)piperazin-1-yl)methanone) and showed that its anti-tubercular activity is attributable to inhibition of inosine-5′-monophosphate dehydrogenase (IMPDH) in Mycobacterium tuberculosis. In the present study, we explored the structure–activity relationship around compound 1 by synthesizing and evaluating the inhibitory activity of analogues against M. tuberculosis IMPDH in biochemical and whole-cell assays. X-ray crystallography was performed to elucidate the mode of binding of selected analogues to IMPDH. We establish the importance of the cyclohexyl, piperazine and isoquinoline rings for activity, and report the identification of an analogue with IMPDH-selective activity against a mutant of M. tuberculosis that is highly resistant to compound 1. We also show that the nitrogen in urea analogues is required for anti-tubercular activity and identify benzylurea derivatives as promising inhibitors that warrant further investigation. Forty-eight analogues of 1-(5-isoquinolinesulfonyl)piperazine were synthesized. Biochemical, whole-cell, and X-ray studies were performed to elucidate the IMPDH inhibition. Piperazine and isoquinoline rings were essential for target-selective whole-cell activity. Compound 47 showed improved IC50 against the MtbIMPDH and maintained on-target whole-cell activity. Compound 21 showed activity against IMPDH in both wild type M. tuberculosis and a resistant mutant of compound 1.
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24
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Chacko S, Boshoff HIM, Singh V, Ferraris DM, Gollapalli DR, Zhang M, Lawson AP, Pepi MJ, Joachimiak A, Rizzi M, Mizrahi V, Cuny GD, Hedstrom L. Expanding Benzoxazole-Based Inosine 5'-Monophosphate Dehydrogenase (IMPDH) Inhibitor Structure-Activity As Potential Antituberculosis Agents. J Med Chem 2018; 61:4739-4756. [PMID: 29746130 DOI: 10.1021/acs.jmedchem.7b01839] [Citation(s) in RCA: 31] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
New drugs and molecular targets are urgently needed to address the emergence and spread of drug-resistant tuberculosis. Mycobacterium tuberculosis ( Mtb) inosine 5'-monophosphate dehydrogenase 2 ( MtbIMPDH2) is a promising yet controversial potential target. The inhibition of MtbIMPDH2 blocks the biosynthesis of guanine nucleotides, but high concentrations of guanine can potentially rescue the bacteria. Herein we describe an expansion of the structure-activity relationship (SAR) for the benzoxazole series of MtbIMPDH2 inhibitors and demonstrate that minimum inhibitory concentrations (MIC) of ≤1 μM can be achieved. The antibacterial activity of the most promising compound, 17b (Q151), is derived from the inhibition of MtbIMPDH2 as demonstrated by conditional knockdown and resistant strains. Importantly, guanine does not change the MIC of 17b, alleviating the concern that guanine salvage can protect Mtb in vivo. These findings suggest that MtbIMPDH2 is a vulnerable target for tuberculosis.
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Affiliation(s)
| | - Helena I M Boshoff
- Tuberculosis Research Section , National Institute of Allergy and Infectious Diseases , Bethesda , Maryland 20892 , United States
| | - Vinayak Singh
- Department of Drug Discovery and Development & Institute of Infectious Disease and Molecular Medicine , H3D Drug Discovery and Development Centre, University of Cape Town , Rondebosch , Cape Town 7701 , South Africa
| | - Davide M Ferraris
- Dipartimento di Scienze del Farmaco , Universitá del Piemonte Orientale , Via Bovio 6 , 28100 Novara , Italy
| | | | | | | | | | - Andrzej Joachimiak
- Center for Structural Genomics of Infectious Diseases and Department of Biochemistry and Molecular Biology , University of Chicago , Chicago , Illinois 60557 , United States.,Structural Biology Center, Biosciences , Argonne National Laboratory , 9700 S. Cass Avenue, Argonne , Illinois 60439 , United States
| | - Menico Rizzi
- Dipartimento di Scienze del Farmaco , Universitá del Piemonte Orientale , Via Bovio 6 , 28100 Novara , Italy
| | - Valerie Mizrahi
- MRC/NHLS/UCT Molecular Mycobacteriology Research Unit & DST/NRF Centre of Excellence for Biomedical TB Research, Institute of Infectious Disease and Molecular Medicine & Department of Pathology , University of Cape Town , Anzio Road , Observatory 7925 , South Africa
| | - Gregory D Cuny
- Department of Pharmacological and Pharmaceutical Sciences, College of Pharmacy , University of Houston , Health Building 2, 4849 Calhoun Road , Houston , Texas 77204 , United States
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25
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Sahu NU, Singh V, Ferraris DM, Rizzi M, Kharkar PS. Hit discovery of Mycobacterium tuberculosis inosine 5'-monophosphate dehydrogenase, GuaB2, inhibitors. Bioorg Med Chem Lett 2018; 28:1714-1718. [PMID: 29699922 DOI: 10.1016/j.bmcl.2018.04.045] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2018] [Revised: 04/13/2018] [Accepted: 04/17/2018] [Indexed: 02/05/2023]
Abstract
Tuberculosis remains a global concern. There is an urgent need of newer antitubercular drugs due to the development of resistant forms of Mycobacterium tuberculosis (Mtb). Inosine 5'-monophosphate dehydrogenase (IMPDH), guaB2, of Mtb, required for guanine nucleotide biosynthesis, is an attractive target for drug development. In this study, we screened a focused library of 73 drug-like molecules with desirable calculated/predicted physicochemical properties, for growth inhibitory activity against drug-sensitive MtbH37Rv. The eight hits and mycophenolic acid, a prototype IMPDH inhibitor, were further evaluated for activity on purified Mtb-GuaB2 enzyme, target selectivity using a conditional knockdown mutant of guaB2 in Mtb, followed by cross-resistance to IMPDH inhibitor-resistant SRMV2.6 strain of Mtb, and activity on human IMPDH2 isoform. One of the hits, 13, a 5-amidophthalide derivative, has shown growth inhibitory potential and target specificity against the Mtb-GuaB2 enzyme. The hit, 13, is a promising molecule with potential for further development as an antitubercular agent.
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Affiliation(s)
- Niteshkumar U Sahu
- Department of Pharmaceutical Chemistry, SPP School of Pharmacy & Technology Management, SVKM's NMIMS, V.L. Mehta Road, Vile Parle (West), Mumbai 400 056, India
| | - Vinayak Singh
- Drug Discovery and Development Centre (H3D), University of Cape Town, Rondebosch 7701, Cape Town, South Africa; South African Medical Research Council Drug Discovery and Development Research Unit, Department of Chemistry and Institute of Infectious Disease and Molecular Medicine, University of Cape Town, Rondebosch 7701, South Africa
| | - Davide M Ferraris
- Dipartimento di Scienze del Farmaco, Università del Piemonte Orientale, Via Bovio 6, 28100 Novara, Italy
| | - Menico Rizzi
- Dipartimento di Scienze del Farmaco, Università del Piemonte Orientale, Via Bovio 6, 28100 Novara, Italy
| | - Prashant S Kharkar
- Department of Pharmaceutical Chemistry, SPP School of Pharmacy & Technology Management, SVKM's NMIMS, V.L. Mehta Road, Vile Parle (West), Mumbai 400 056, India.
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26
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Trapero A, Pacitto A, Singh V, Sabbah M, Coyne AG, Mizrahi V, Blundell TL, Ascher DB, Abell C. Fragment-Based Approach to Targeting Inosine-5'-monophosphate Dehydrogenase (IMPDH) from Mycobacterium tuberculosis. J Med Chem 2018; 61:2806-2822. [PMID: 29547284 PMCID: PMC5900554 DOI: 10.1021/acs.jmedchem.7b01622] [Citation(s) in RCA: 41] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
![]()
Tuberculosis (TB)
remains a major cause of mortality worldwide,
and improved treatments are needed to combat emergence of drug resistance.
Inosine 5′-monophosphate dehydrogenase (IMPDH), a crucial enzyme
required for de novo synthesis of guanine nucleotides,
is an attractive TB drug target. Herein, we describe the identification
of potent IMPDH inhibitors using fragment-based screening and structure-based
design techniques. Screening of a fragment library for Mycobacterium
thermoresistible (Mth) IMPDH ΔCBS
inhibitors identified a low affinity phenylimidazole derivative. X-ray
crystallography of the Mth IMPDH ΔCBS–IMP–inhibitor
complex revealed that two molecules of the fragment were bound in
the NAD binding pocket of IMPDH. Linking the two molecules of the
fragment afforded compounds with more than 1000-fold improvement in
IMPDH affinity over the initial fragment hit.
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Affiliation(s)
- Ana Trapero
- Department of Chemistry , University of Cambridge , Lensfield Road , Cambridge CB2 1EW , United Kingdom
| | - Angela Pacitto
- Department of Biochemistry , University of Cambridge , 80 Tennis Court Road , Cambridge CB2 1GA , United Kingdom
| | - Vinayak Singh
- MRC/NHLS/UCT Molecular Mycobacteriology Research Unit & DST/NRF Centre of Excellence for Biomedical TB Research, Institute of Infectious Disease and Molecular Medicine and Division of Medical Microbiology, Faculty of Health Sciences , University of Cape Town , Rondebosch 7701 , Cape Town , South Africa
| | - Mohamad Sabbah
- Department of Chemistry , University of Cambridge , Lensfield Road , Cambridge CB2 1EW , United Kingdom
| | - Anthony G Coyne
- Department of Chemistry , University of Cambridge , Lensfield Road , Cambridge CB2 1EW , United Kingdom
| | - Valerie Mizrahi
- MRC/NHLS/UCT Molecular Mycobacteriology Research Unit & DST/NRF Centre of Excellence for Biomedical TB Research, Institute of Infectious Disease and Molecular Medicine and Division of Medical Microbiology, Faculty of Health Sciences , University of Cape Town , Rondebosch 7701 , Cape Town , South Africa
| | - Tom L Blundell
- Department of Biochemistry , University of Cambridge , 80 Tennis Court Road , Cambridge CB2 1GA , United Kingdom
| | - David B Ascher
- Department of Biochemistry , University of Cambridge , 80 Tennis Court Road , Cambridge CB2 1GA , United Kingdom.,Department of Biochemistry and Molecular Biology, Bio21 Institute , University of Melbourne , 30 Flemington Road , Parkville , Victoria 3052 , Australia
| | - Chris Abell
- Department of Chemistry , University of Cambridge , Lensfield Road , Cambridge CB2 1EW , United Kingdom
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27
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Łukowska-Chojnacka E, Kowalkowska A, Napiórkowska A. Lipase-catalyzed kinetic resolution of novel antitubercular benzoxazole derivatives. Chirality 2017; 30:457-468. [DOI: 10.1002/chir.22806] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2017] [Revised: 10/11/2017] [Accepted: 11/22/2017] [Indexed: 01/31/2023]
Affiliation(s)
| | - Anna Kowalkowska
- Faculty of Chemistry; Warsaw University of Technology; Warsaw Poland
| | - Agnieszka Napiórkowska
- Microbiology Department; National Tuberculosis and Lung Diseases Research Institute; Warsaw Poland
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28
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Benzoxazoles, Phthalazinones, and Arylurea-Based Compounds with IMP Dehydrogenase-Independent Antibacterial Activity against Francisella tularensis. Antimicrob Agents Chemother 2017; 61:AAC.00939-17. [PMID: 28739786 DOI: 10.1128/aac.00939-17] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2017] [Accepted: 07/07/2017] [Indexed: 01/06/2023] Open
Abstract
Francisella tularensis is the causative agent of tularemia and a potential biowarfare agent. The virulence of F. tularensis is decreased by deletion of guaB, the gene encoding IMP dehydrogenase (IMPDH), suggesting that this enzyme is a target for antibacterial design. Here we report that F. tularensis growth is blocked by inhibitors of bacterial IMPDHs. Seventeen compounds from two different frameworks, designated the D and Q series, display antibacterial activities with MICs of <1 μM. These compounds are also active against intracellular infections. Surprisingly, antibacterial activity does not correlate with IMPDH inhibition. In addition, the presence of guanine does not affect the antibacterial activity of most compounds, nor does the deletion of guaB These observations suggest that antibacterial activity derives from inhibition of another target(s). Moreover, D compounds display antibacterial activity only against F. tularensis, suggesting the presence of a unique target or uptake mechanism. A ΔguaB mutant resistant to compound D73 contained a missense mutation (Gly45Cys) in nuoB, which encodes a subunit of bacterial complex I. Overexpression of the nuoB mutant conferred resistance to D73 in both wild-type and ΔguaB strains. This strain was not resistant to Q compounds, suggesting that a different off-target mechanism operates for these compounds. Several Q compounds are also effective against Mycobacterium tuberculosis, in which a second target has also been implicated, in addition to IMPDH. The fortuitous presence of multiple targets with overlapping structure-activity relationships presents an intriguing opportunity for the development of robust antibiotics that may avoid the emergence of resistance.
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29
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Núñez-Díaz JA, Fumanal M, Viguera E, Moriñigo MA, Balebona MC. Use of in vivo induced technology to identify antigens expressed by Photobacterium damselae subsp. piscicida during infection of Senegalese sole (Solea senegalensis). FISH & SHELLFISH IMMUNOLOGY 2017; 64:446-456. [PMID: 28359946 DOI: 10.1016/j.fsi.2017.03.044] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/06/2017] [Revised: 03/22/2017] [Accepted: 03/26/2017] [Indexed: 06/07/2023]
Abstract
Photobacterium damselae subsp. piscicida (Phdp), the causative agent of photobacteriosis, is an important pathogen in marine aquaculture that affects many different fish species worldwide, including Solea senegalensis, an important fish species for aquaculture in the south of Europe. Bacteria express different repertoires of proteins in response to environmental conditions and when invading a host, sense in vivo environment and adapt by changing the expression of specific proteins. In the case of pathogens, identification of genes with up-regulated expression in vivo compared to in vitro conditions might give an insight into the genes relevant to the bacterial virulence. In the present work, in vivo induced antigen technology (IVIAT) has been used to search for Phdp genes only expressed or up-regulated in infected S. senegalensis. An expression library from Phdp was assayed against pooled sera from convalescent S. senegalensis specimens and 18 clones were positive, indicating that proteins encoded are expressed by Phdp during S. senegalensis infection and are immunogenic for this fish species. In addition, five proteins were reactive against adsorbed sera, indicating their in vivo induced character. Inosine-5'-monophosphate dehydrogenase, serine hydroxy methyltransferase and alanyl-tRNA synthethase, involved in aminoacid and nucleotide metabolism, the protein with antioxidant activity alkyl hydroperoxide reductase and a non-ribosomal peptide synthetase responsible for the synthesis of the siderophore piscibactin have been identified as antigens induced in Phdp during S. senegalensis infection. Proteins induced during in vivo growth of Phdp represent promising targets for the development of novel antimicrobial or prophylactic agents in the treatment and prevention of photobacteriosis.
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Affiliation(s)
- J A Núñez-Díaz
- Universidad de Málaga, Departamento de Microbiología, Campus de Teatinos s/n, 29071 Málaga, Spain
| | - M Fumanal
- Universidad de Málaga, Departamento de Microbiología, Campus de Teatinos s/n, 29071 Málaga, Spain
| | - E Viguera
- Universidad de Málaga, Área de Genética, Campus de Teatinos s/n, 29071 Málaga, Spain
| | - M A Moriñigo
- Universidad de Málaga, Departamento de Microbiología, Campus de Teatinos s/n, 29071 Málaga, Spain
| | - M C Balebona
- Universidad de Málaga, Departamento de Microbiología, Campus de Teatinos s/n, 29071 Málaga, Spain.
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30
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Singh V, Donini S, Pacitto A, Sala C, Hartkoorn RC, Dhar N, Keri G, Ascher DB, Mondésert G, Vocat A, Lupien A, Sommer R, Vermet H, Lagrange S, Buechler J, Warner D, McKinney JD, Pato J, Cole ST, Blundell TL, Rizzi M, Mizrahi V. The Inosine Monophosphate Dehydrogenase, GuaB2, Is a Vulnerable New Bactericidal Drug Target for Tuberculosis. ACS Infect Dis 2017; 3:5-17. [PMID: 27726334 PMCID: PMC5241705 DOI: 10.1021/acsinfecdis.6b00102] [Citation(s) in RCA: 72] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2016] [Indexed: 12/14/2022]
Abstract
VCC234718, a molecule with growth inhibitory activity against Mycobacterium tuberculosis (Mtb), was identified by phenotypic screening of a 15344-compound library. Sequencing of a VCC234718-resistant mutant identified a Y487C substitution in the inosine monophosphate dehydrogenase, GuaB2, which was subsequently validated to be the primary molecular target of VCC234718 in Mtb. VCC234718 inhibits Mtb GuaB2 with a Ki of 100 nM and is uncompetitive with respect to IMP and NAD+. This compound binds at the NAD+ site, after IMP has bound, and makes direct interactions with IMP; therefore, the inhibitor is by definition uncompetitive. VCC234718 forms strong pi interactions with the Y487 residue side chain from the adjacent protomer in the tetramer, explaining the resistance-conferring mutation. In addition to sensitizing Mtb to VCC234718, depletion of GuaB2 was bactericidal in Mtb in vitro and in macrophages. When supplied at a high concentration (≥125 μM), guanine alleviated the toxicity of VCC234718 treatment or GuaB2 depletion via purine salvage. However, transcriptional silencing of guaB2 prevented Mtb from establishing an infection in mice, confirming that Mtb has limited access to guanine in this animal model. Together, these data provide compelling validation of GuaB2 as a new tuberculosis drug target.
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Affiliation(s)
- Vinayak Singh
- MRC/NHLS/UCT Molecular Mycobacteriology
Research Unit & DST/NRF Centre of Excellence for Biomedical TB
Research, Institute of Infectious Disease and Molecular Medicine &
Department of Pathology, University of Cape
Town, Anzio Road, Observatory 7925, South Africa
| | - Stefano Donini
- Dipartimento di Scienze del Farmaco, University of Piemonte Orientale, Via Bovio 6, 28100 Novara, Italy
| | - Angela Pacitto
- Department of Biochemistry, University of Cambridge, 80 Tennis Court Road, Cambridge CB2 1GA, United Kingdom
| | - Claudia Sala
- Ecole Polytechnique Fédérale de Lausanne, Global Health Institute, Station 19, 1015 Lausanne, Switzerland
| | - Ruben C. Hartkoorn
- Ecole Polytechnique Fédérale de Lausanne, Global Health Institute, Station 19, 1015 Lausanne, Switzerland
| | - Neeraj Dhar
- Ecole Polytechnique Fédérale de Lausanne, Global Health Institute, Station 19, 1015 Lausanne, Switzerland
| | - Gyorgy Keri
- Vichem
Chemie, Herman Ottó
út 15, Budapest, 1022 Hungary
| | - David B. Ascher
- Department of Biochemistry, University of Cambridge, 80 Tennis Court Road, Cambridge CB2 1GA, United Kingdom
| | - Guillaume Mondésert
- Sanofi-Aventis Research
& Development, Infectious Diseases Unit,
Biology Group, Campus Mérieux, 1541 avenue Marcel Mérieux, 69280 Marcy L’Etoile, France
| | - Anthony Vocat
- Ecole Polytechnique Fédérale de Lausanne, Global Health Institute, Station 19, 1015 Lausanne, Switzerland
| | - Andréanne Lupien
- Ecole Polytechnique Fédérale de Lausanne, Global Health Institute, Station 19, 1015 Lausanne, Switzerland
| | - Raphael Sommer
- Ecole Polytechnique Fédérale de Lausanne, Global Health Institute, Station 19, 1015 Lausanne, Switzerland
| | - Hélène Vermet
- Sanofi-Aventis Research
& Development, Infectious Diseases Unit,
Biology Group, Campus Mérieux, 1541 avenue Marcel Mérieux, 69280 Marcy L’Etoile, France
| | - Sophie Lagrange
- Sanofi-Aventis Research
& Development, Infectious Diseases Unit,
Biology Group, Campus Mérieux, 1541 avenue Marcel Mérieux, 69280 Marcy L’Etoile, France
| | - Joe Buechler
- Alere (San Diego), Summer Ridge Road, San Diego, California 92121, United States
| | - Digby
F. Warner
- MRC/NHLS/UCT Molecular Mycobacteriology
Research Unit & DST/NRF Centre of Excellence for Biomedical TB
Research, Institute of Infectious Disease and Molecular Medicine &
Department of Pathology, University of Cape
Town, Anzio Road, Observatory 7925, South Africa
| | - John D. McKinney
- Ecole Polytechnique Fédérale de Lausanne, Global Health Institute, Station 19, 1015 Lausanne, Switzerland
| | - Janos Pato
- Vichem
Chemie, Herman Ottó
út 15, Budapest, 1022 Hungary
| | - Stewart T. Cole
- Ecole Polytechnique Fédérale de Lausanne, Global Health Institute, Station 19, 1015 Lausanne, Switzerland
| | - Tom L. Blundell
- Department of Biochemistry, University of Cambridge, 80 Tennis Court Road, Cambridge CB2 1GA, United Kingdom
| | - Menico Rizzi
- Dipartimento di Scienze del Farmaco, University of Piemonte Orientale, Via Bovio 6, 28100 Novara, Italy
| | - Valerie Mizrahi
- MRC/NHLS/UCT Molecular Mycobacteriology
Research Unit & DST/NRF Centre of Excellence for Biomedical TB
Research, Institute of Infectious Disease and Molecular Medicine &
Department of Pathology, University of Cape
Town, Anzio Road, Observatory 7925, South Africa
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31
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Park Y, Pacitto A, Bayliss T, Cleghorn LAT, Wang Z, Hartman T, Arora K, Ioerger TR, Sacchettini J, Rizzi M, Donini S, Blundell TL, Ascher DB, Rhee K, Breda A, Zhou N, Dartois V, Jonnala SR, Via LE, Mizrahi V, Epemolu O, Stojanovski L, Simeons F, Osuna-Cabello M, Ellis L, MacKenzie CJ, Smith ARC, Davis SH, Murugesan D, Buchanan KI, Turner PA, Huggett M, Zuccotto F, Rebollo-Lopez MJ, Lafuente-Monasterio MJ, Sanz O, Diaz GS, Lelièvre J, Ballell L, Selenski C, Axtman M, Ghidelli-Disse S, Pflaumer H, Bösche M, Drewes G, Freiberg GM, Kurnick MD, Srikumaran M, Kempf DJ, Green SR, Ray PC, Read K, Wyatt P, Barry CE, Boshoff HI. Essential but Not Vulnerable: Indazole Sulfonamides Targeting Inosine Monophosphate Dehydrogenase as Potential Leads against Mycobacterium tuberculosis. ACS Infect Dis 2017; 3:18-33. [PMID: 27704782 DOI: 10.1021/acsinfecdis.6b00103] [Citation(s) in RCA: 69] [Impact Index Per Article: 9.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
A potent, noncytotoxic indazole sulfonamide was identified by high-throughput screening of >100,000 synthetic compounds for activity against Mycobacterium tuberculosis (Mtb). This noncytotoxic compound did not directly inhibit cell wall biogenesis but triggered a slow lysis of Mtb cells as measured by release of intracellular green fluorescent protein (GFP). Isolation of resistant mutants followed by whole-genome sequencing showed an unusual gene amplification of a 40 gene region spanning from Rv3371 to Rv3411c and in one case a potential promoter mutation upstream of guaB2 (Rv3411c) encoding inosine monophosphate dehydrogenase (IMPDH). Subsequent biochemical validation confirmed direct inhibition of IMPDH by an uncompetitive mode of inhibition, and growth inhibition could be rescued by supplementation with guanine, a bypass mechanism for the IMPDH pathway. Beads containing immobilized indazole sulfonamides specifically interacted with IMPDH in cell lysates. X-ray crystallography of the IMPDH-IMP-inhibitor complex revealed that the primary interactions of these compounds with IMPDH were direct pi-pi interactions with the IMP substrate. Advanced lead compounds in this series with acceptable pharmacokinetic properties failed to show efficacy in acute or chronic murine models of tuberculosis (TB). Time-kill experiments in vitro suggest that sustained exposure to drug concentrations above the minimum inhibitory concentration (MIC) for 24 h were required for a cidal effect, levels that have been difficult to achieve in vivo. Direct measurement of guanine levels in resected lung tissue from tuberculosis-infected animals and patients revealed 0.5-2 mM concentrations in caseum and normal lung tissue. The high lesional levels of guanine and the slow lytic, growth-rate-dependent effect of IMPDH inhibition pose challenges to developing drugs against this target for use in treating TB.
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Affiliation(s)
- Yumi Park
- Tuberculosis
Research Section, Laboratory of Clinical Infectious Diseases, National
Institute of Allergy and Infectious Disease, National Institutes of Health, Bethesda, Maryland 20892-3206, United States
| | - Angela Pacitto
- Department
of Biochemistry, University of Cambridge, Cambridge CB2 1GA, United Kingdom
| | - Tracy Bayliss
- Drug
Discovery Unit, College of Life Sciences, James Black Centre, University of Dundee, Dundee DD1 5EH, United Kingdom
| | - Laura A. T. Cleghorn
- Drug
Discovery Unit, College of Life Sciences, James Black Centre, University of Dundee, Dundee DD1 5EH, United Kingdom
| | - Zhe Wang
- Division
of Infectious Diseases, Department of Medicine, Weill Cornell Medical College, New York, New York 10065, United States
| | - Travis Hartman
- Division
of Infectious Diseases, Department of Medicine, Weill Cornell Medical College, New York, New York 10065, United States
| | - Kriti Arora
- Tuberculosis
Research Section, Laboratory of Clinical Infectious Diseases, National
Institute of Allergy and Infectious Disease, National Institutes of Health, Bethesda, Maryland 20892-3206, United States
| | - Thomas R. Ioerger
- Department of Computer Science and Engineering, Texas A&M University, College Station, Texas 77843, United States
| | - Jim Sacchettini
- Department of Biochemistry & Biophysics, Texas A&M University, College Station, Texas 77843, United States
| | - Menico Rizzi
- Dipartimento
di Scienze del Farmaco, University of Piemonte Orientale, Via Bovio
6, 28100 Novara, Italy
| | - Stefano Donini
- Dipartimento
di Scienze del Farmaco, University of Piemonte Orientale, Via Bovio
6, 28100 Novara, Italy
| | - Tom L. Blundell
- Department
of Biochemistry, University of Cambridge, Cambridge CB2 1GA, United Kingdom
| | - David B. Ascher
- Department
of Biochemistry, University of Cambridge, Cambridge CB2 1GA, United Kingdom
| | - Kyu Rhee
- Division
of Infectious Diseases, Department of Medicine, Weill Cornell Medical College, New York, New York 10065, United States
| | - Ardala Breda
- Department of Biochemistry & Biophysics, Texas A&M University, College Station, Texas 77843, United States
| | - Nian Zhou
- Department of Biochemistry & Biophysics, Texas A&M University, College Station, Texas 77843, United States
| | - Veronique Dartois
- Public
Health Research Institute, New Jersey Medical School, Rutgers, The State University of New Jersey, Newark, New Jersey 07103, United States
| | - Surendranadha Reddy Jonnala
- Tuberculosis
Research Section, Laboratory of Clinical Infectious Diseases, National
Institute of Allergy and Infectious Disease, National Institutes of Health, Bethesda, Maryland 20892-3206, United States
| | - Laura E. Via
- Tuberculosis
Research Section, Laboratory of Clinical Infectious Diseases, National
Institute of Allergy and Infectious Disease, National Institutes of Health, Bethesda, Maryland 20892-3206, United States
- MRC/NHLS/UCT
Molecular Mycobacteriology Research Unit, Institute of Infectious
Disease and Molecular Medicine, University of Cape Town, Rondebosch 7700, South Africa
| | - Valerie Mizrahi
- MRC/NHLS/UCT
Molecular Mycobacteriology Research Unit, Institute of Infectious
Disease and Molecular Medicine, University of Cape Town, Rondebosch 7700, South Africa
| | - Ola Epemolu
- Drug
Discovery Unit, College of Life Sciences, James Black Centre, University of Dundee, Dundee DD1 5EH, United Kingdom
| | - Laste Stojanovski
- Drug
Discovery Unit, College of Life Sciences, James Black Centre, University of Dundee, Dundee DD1 5EH, United Kingdom
| | - Fred Simeons
- Drug
Discovery Unit, College of Life Sciences, James Black Centre, University of Dundee, Dundee DD1 5EH, United Kingdom
| | - Maria Osuna-Cabello
- Drug
Discovery Unit, College of Life Sciences, James Black Centre, University of Dundee, Dundee DD1 5EH, United Kingdom
| | - Lucy Ellis
- Drug
Discovery Unit, College of Life Sciences, James Black Centre, University of Dundee, Dundee DD1 5EH, United Kingdom
| | - Claire J. MacKenzie
- Drug
Discovery Unit, College of Life Sciences, James Black Centre, University of Dundee, Dundee DD1 5EH, United Kingdom
| | - Alasdair R. C. Smith
- Drug
Discovery Unit, College of Life Sciences, James Black Centre, University of Dundee, Dundee DD1 5EH, United Kingdom
| | - Susan H. Davis
- Drug
Discovery Unit, College of Life Sciences, James Black Centre, University of Dundee, Dundee DD1 5EH, United Kingdom
| | - Dinakaran Murugesan
- Drug
Discovery Unit, College of Life Sciences, James Black Centre, University of Dundee, Dundee DD1 5EH, United Kingdom
| | - Kirsteen I. Buchanan
- Drug
Discovery Unit, College of Life Sciences, James Black Centre, University of Dundee, Dundee DD1 5EH, United Kingdom
| | - Penelope A. Turner
- Drug
Discovery Unit, College of Life Sciences, James Black Centre, University of Dundee, Dundee DD1 5EH, United Kingdom
| | - Margaret Huggett
- Drug
Discovery Unit, College of Life Sciences, James Black Centre, University of Dundee, Dundee DD1 5EH, United Kingdom
| | - Fabio Zuccotto
- Drug
Discovery Unit, College of Life Sciences, James Black Centre, University of Dundee, Dundee DD1 5EH, United Kingdom
| | - Maria Jose Rebollo-Lopez
- Diseases
of the Developing World, GlaxoSmithKline, Calle Severo Ochoa 2, 28760 Tres Cantos, Madrid, Spain
| | | | - Olalla Sanz
- Diseases
of the Developing World, GlaxoSmithKline, Calle Severo Ochoa 2, 28760 Tres Cantos, Madrid, Spain
| | - Gracia Santos Diaz
- Diseases
of the Developing World, GlaxoSmithKline, Calle Severo Ochoa 2, 28760 Tres Cantos, Madrid, Spain
| | - Joël Lelièvre
- Diseases
of the Developing World, GlaxoSmithKline, Calle Severo Ochoa 2, 28760 Tres Cantos, Madrid, Spain
| | - Lluis Ballell
- Diseases
of the Developing World, GlaxoSmithKline, Calle Severo Ochoa 2, 28760 Tres Cantos, Madrid, Spain
| | - Carolyn Selenski
- GlaxoSmithKline, 5 Crescent Drive, Philadelphia, Pennsylvania 19112, United States
| | - Matthew Axtman
- GlaxoSmithKline, 5 Crescent Drive, Philadelphia, Pennsylvania 19112, United States
| | - Sonja Ghidelli-Disse
- Cellzome
GmbH, Molecular Discovery Research, GlaxoSmithKline, Meyerhofstrasse 1, 69117 Heidelberg, Germany
| | - Hannah Pflaumer
- Cellzome
GmbH, Molecular Discovery Research, GlaxoSmithKline, Meyerhofstrasse 1, 69117 Heidelberg, Germany
| | - Markus Bösche
- Cellzome
GmbH, Molecular Discovery Research, GlaxoSmithKline, Meyerhofstrasse 1, 69117 Heidelberg, Germany
| | - Gerard Drewes
- Cellzome
GmbH, Molecular Discovery Research, GlaxoSmithKline, Meyerhofstrasse 1, 69117 Heidelberg, Germany
| | - Gail M. Freiberg
- AbbVie Molecular Characterization, 1 North Waukegan Road, North Chicago, Illinois 60064, United States
| | - Matthew D. Kurnick
- AbbVie Molecular Characterization, 1 North Waukegan Road, North Chicago, Illinois 60064, United States
| | - Myron Srikumaran
- AbbVie Molecular Characterization, 1 North Waukegan Road, North Chicago, Illinois 60064, United States
| | - Dale J. Kempf
- AbbVie Molecular Characterization, 1 North Waukegan Road, North Chicago, Illinois 60064, United States
| | - Simon R. Green
- Drug
Discovery Unit, College of Life Sciences, James Black Centre, University of Dundee, Dundee DD1 5EH, United Kingdom
| | - Peter C. Ray
- Drug
Discovery Unit, College of Life Sciences, James Black Centre, University of Dundee, Dundee DD1 5EH, United Kingdom
| | - Kevin Read
- Drug
Discovery Unit, College of Life Sciences, James Black Centre, University of Dundee, Dundee DD1 5EH, United Kingdom
| | - Paul Wyatt
- Drug
Discovery Unit, College of Life Sciences, James Black Centre, University of Dundee, Dundee DD1 5EH, United Kingdom
| | - Clifton E. Barry
- Tuberculosis
Research Section, Laboratory of Clinical Infectious Diseases, National
Institute of Allergy and Infectious Disease, National Institutes of Health, Bethesda, Maryland 20892-3206, United States
- MRC/NHLS/UCT
Molecular Mycobacteriology Research Unit, Institute of Infectious
Disease and Molecular Medicine, University of Cape Town, Rondebosch 7700, South Africa
| | - Helena I. Boshoff
- Tuberculosis
Research Section, Laboratory of Clinical Infectious Diseases, National
Institute of Allergy and Infectious Disease, National Institutes of Health, Bethesda, Maryland 20892-3206, United States
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32
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Cox JAG, Mugumbate G, Del Peral LVG, Jankute M, Abrahams KA, Jervis P, Jackenkroll S, Perez A, Alemparte C, Esquivias J, Lelièvre J, Ramon F, Barros D, Ballell L, Besra GS. Novel inhibitors of Mycobacterium tuberculosis GuaB2 identified by a target based high-throughput phenotypic screen. Sci Rep 2016; 6:38986. [PMID: 27982051 PMCID: PMC5159837 DOI: 10.1038/srep38986] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2016] [Accepted: 11/16/2016] [Indexed: 12/16/2022] Open
Abstract
High-throughput phenotypic screens have re-emerged as screening tools in antibiotic discovery. The advent of such technologies has rapidly accelerated the identification of 'hit' compounds. A pre-requisite to medicinal chemistry optimisation programmes required to improve the drug-like properties of a 'hit' molecule is identification of its mode of action. Herein, we have combined phenotypic screening with a biased target-specific screen. The inosine monophosphate dehydrogenase (IMPDH) protein GuaB2 has been identified as a drugable target in Mycobacterium tuberculosis, however previously identified compounds lack the desired characteristics necessary for further development into lead-like molecules. This study has identified 7 new chemical series from a high-throughput resistance-based phenotypic screen using Mycobacterium bovis BCG over-expressing GuaB2. Hit compounds were identified in a single shot high-throughput screen, validated by dose response and subjected to further biochemical analysis. The compounds were also assessed using molecular docking experiments, providing a platform for their further optimisation using medicinal chemistry. This work demonstrates the versatility and potential of GuaB2 as an anti-tubercular drug target.
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Affiliation(s)
- Jonathan A. G. Cox
- Life and Health Sciences, Aston University, Aston Triangle, Birmingham B4 7ET, UK
| | - Grace Mugumbate
- European Molecular Biology Laboratory, European Bioinformatics Institute (EMBL-EBI), Wellcome Trust Genome Campus, Hinxton, Cambridge, United Kingdom, CB10 1SD
| | - Laura Vela-Glez Del Peral
- Molecular Discovery Research, GlaxoSmithKline, Santiago Grisolia 4, 28760 Tres Cantos, Madrid, Spain
| | - Monika Jankute
- School of Biosciences, University of Birmingham, Edgbaston, Birmingham B15 2TT, UK
| | | | - Peter Jervis
- School of Biosciences, University of Birmingham, Edgbaston, Birmingham B15 2TT, UK
| | - Stefan Jackenkroll
- School of Biosciences, University of Birmingham, Edgbaston, Birmingham B15 2TT, UK
| | - Arancha Perez
- Diseases of the Developing World, GlaxoSmithKline, Severo Ochoa 2, 28760 Tres Cantos, Madrid, Spain
| | - Carlos Alemparte
- Diseases of the Developing World, GlaxoSmithKline, Severo Ochoa 2, 28760 Tres Cantos, Madrid, Spain
| | - Jorge Esquivias
- Diseases of the Developing World, GlaxoSmithKline, Severo Ochoa 2, 28760 Tres Cantos, Madrid, Spain
| | - Joël Lelièvre
- Diseases of the Developing World, GlaxoSmithKline, Severo Ochoa 2, 28760 Tres Cantos, Madrid, Spain
| | - Fernando Ramon
- Molecular Discovery Research, GlaxoSmithKline, Santiago Grisolia 4, 28760 Tres Cantos, Madrid, Spain
| | - David Barros
- Diseases of the Developing World, GlaxoSmithKline, Severo Ochoa 2, 28760 Tres Cantos, Madrid, Spain
| | - Lluis Ballell
- Diseases of the Developing World, GlaxoSmithKline, Severo Ochoa 2, 28760 Tres Cantos, Madrid, Spain
| | - Gurdyal S. Besra
- School of Biosciences, University of Birmingham, Edgbaston, Birmingham B15 2TT, UK
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