1
|
Bashore F, Annor-Gyamfi J, Du Y, Katis V, Nwogbo F, Flax RG, Frye SV, Pearce KH, Fu H, Willson TM, Drewry DH, Axtman AD. Fused Tetrahydroquinolines Are Interfering with Your Assay. J Med Chem 2023; 66:14434-14446. [PMID: 37874947 PMCID: PMC10641811 DOI: 10.1021/acs.jmedchem.3c01277] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2023] [Revised: 09/12/2023] [Accepted: 10/06/2023] [Indexed: 10/26/2023]
Abstract
Tricyclic tetrahydroquinolines (THQs) have been repeatedly reported as hits across a diverse range of high-throughput screening (HTS) campaigns. The activities of these compounds, however, are likely due to reactive byproducts that interfere with the assay. As a lesser studied class of pan-assay interference compounds, the mechanism by which fused THQs react with protein targets remains largely unknown. During HTS follow-up, we characterized the behavior and stability of several fused tricyclic THQs. We synthesized key analogues to pinpoint the cyclopentene ring double bond as a source of reactivity of fused THQs. We found that these compounds degrade in solution under standard laboratory conditions in days. Importantly, these observations make it likely that fused THQs, which are ubiquitously found within small molecule screening libraries, are unlikely the intact parent compounds. We urge deprioritization of tricylic THQ hits in HTS follow-up and caution against the investment of resources to follow-up on these problematic compounds.
Collapse
Affiliation(s)
- Frances
M. Bashore
- Structural
Genomics Consortium, UNC Eshelman School of Pharmacy, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599, United States
| | - Joel Annor-Gyamfi
- Structural
Genomics Consortium, UNC Eshelman School of Pharmacy, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599, United States
| | - Yuhong Du
- Department
of Pharmacology and Chemical Biology, Emory
University School of Medicine, Atlanta, Georgia 30322, United States
- Emory
Chemical Biology Discovery Center, Emory
University School of Medicine, Atlanta, Georgia 30322, United States
| | - Vittorio Katis
- Alzheimer’s
Research UK Oxford Drug Discovery Institute, Centre for Medicines
Discovery, Nuffield Department of Medicine Research Building, Old
Road Campus, University of Oxford, Oxford OX3 7FZ, U.K.
| | - Felix Nwogbo
- UNC
Eshelman School of Pharmacy, Division of Chemical Biology and Medicinal
Chemistry, Center for Integrative Chemical
Biology and Drug Discovery, Chapel
Hill, North Carolina 27599, United States
| | - Raymond G. Flax
- Structural
Genomics Consortium, UNC Eshelman School of Pharmacy, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599, United States
| | - Stephen V. Frye
- UNC
Eshelman School of Pharmacy, Division of Chemical Biology and Medicinal
Chemistry, Center for Integrative Chemical
Biology and Drug Discovery, Chapel
Hill, North Carolina 27599, United States
| | - Kenneth H. Pearce
- UNC
Eshelman School of Pharmacy, Division of Chemical Biology and Medicinal
Chemistry, Center for Integrative Chemical
Biology and Drug Discovery, Chapel
Hill, North Carolina 27599, United States
| | - Haian Fu
- Department
of Pharmacology and Chemical Biology, Emory
University School of Medicine, Atlanta, Georgia 30322, United States
- Emory
Chemical Biology Discovery Center, Emory
University School of Medicine, Atlanta, Georgia 30322, United States
| | - Timothy M. Willson
- Structural
Genomics Consortium, UNC Eshelman School of Pharmacy, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599, United States
| | - David H. Drewry
- Structural
Genomics Consortium, UNC Eshelman School of Pharmacy, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599, United States
- UNC Lineberger
Comprehensive Cancer Center, School of Medicine, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599, United States
| | - Alison D. Axtman
- Structural
Genomics Consortium, UNC Eshelman School of Pharmacy, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599, United States
| |
Collapse
|
2
|
Kayastha F, Herrington NB, Kapadia B, Roychowdhury A, Nanaji N, Kellogg GE, Gartenhaus RB. Novel eIF4A1 inhibitors with anti-tumor activity in lymphoma. Mol Med 2022; 28:101. [PMID: 36058921 PMCID: PMC9441068 DOI: 10.1186/s10020-022-00534-0] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2022] [Accepted: 08/25/2022] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Deregulated translation initiation is implicated extensively in cancer initiation and progression. It is actively pursued as a viable target that circumvents the dependency on oncogenic signaling, a significant factor in current strategies. Eukaryotic translation initiation factor (eIF) 4A plays an essential role in translation initiation by unwinding the secondary structure of messenger RNA (mRNA) upstream of the start codon, enabling active ribosomal recruitment on the downstream genes. Several natural product molecules with similar scaffolds, such as Rocaglamide A (RocA), targeting eIF4A have been reported in the last decade. However, their clinical utilization is still elusive due to several pharmacological limitations. In this study we identified new eIF4A1 inhibitors and their possible mechanisms. METHODS In this report, we conducted a pharmacophore-based virtual screen of RocA complexed with eIF4A and a polypurine RNA strand for novel eIF4A inhibitors from commercially available compounds in the MolPort Database. We performed target-based screening and optimization of active pharmacophores. We assessed the effects of novel compounds on biochemical and cell-based assays for efficacy and mechanistic evaluation. RESULTS We validated three new potent eIF4A inhibitors, RBF197, RBF 203, and RBF 208, which decreased diffuse large B-cell lymphoma (DLBCL) cell viability. Biochemical and cellular studies, molecular docking, and functional assays revealed that thosenovel compounds clamp eIF4A into mRNA in an ATP-independent manner. Moreover, we found that RBF197 and RBF208 significantly depressed eIF4A-dependent oncogene expression as well as the colony formation capacity of DLBCL. Interestingly, exposure of these compounds to non-malignant cells had only minimal impact on their growth and viability. CONCLUSIONS Identified compounds suggest a new strategy for designing novel eIF4A inhibitors.
Collapse
Affiliation(s)
- Forum Kayastha
- McGuire Cancer Center, Hunter Holmes McGuire VA Medical Center, Richmond, VA, USA
- Division of Hematology, Oncology, and Palliative care, Department of Internal Medicine, Massey Cancer Center, Virginia Commonwealth University School of Medicine, Richmond, VA, USA
| | - Noah B Herrington
- Department of Medicinal Chemistry, Institute for Structural Biology, Drug Discovery and Development, Virginia Commonwealth University School of Pharmacy, Richmond, VA, USA
| | - Bandish Kapadia
- McGuire Cancer Center, Hunter Holmes McGuire VA Medical Center, Richmond, VA, USA
- Division of Hematology, Oncology, and Palliative care, Department of Internal Medicine, Massey Cancer Center, Virginia Commonwealth University School of Medicine, Richmond, VA, USA
| | - Anirban Roychowdhury
- McGuire Cancer Center, Hunter Holmes McGuire VA Medical Center, Richmond, VA, USA
- Division of Hematology, Oncology, and Palliative care, Department of Internal Medicine, Massey Cancer Center, Virginia Commonwealth University School of Medicine, Richmond, VA, USA
| | - Nahid Nanaji
- Department of Veteran Affairs, Maryland Healthcare System, Baltimore, MD, USA
| | - Glen E Kellogg
- Department of Medicinal Chemistry, Institute for Structural Biology, Drug Discovery and Development, Virginia Commonwealth University School of Pharmacy, Richmond, VA, USA
| | - Ronald B Gartenhaus
- McGuire Cancer Center, Hunter Holmes McGuire VA Medical Center, Richmond, VA, USA.
- Division of Hematology, Oncology, and Palliative care, Department of Internal Medicine, Massey Cancer Center, Virginia Commonwealth University School of Medicine, Richmond, VA, USA.
| |
Collapse
|
3
|
Bolnykh V, Rossetti G, Rothlisberger U, Carloni P. Expanding the boundaries of ligand–target modeling by exascale calculations. WIRES COMPUTATIONAL MOLECULAR SCIENCE 2021. [DOI: 10.1002/wcms.1535] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Affiliation(s)
- Viacheslav Bolnykh
- Laboratory of Computational Chemistry and Biochemistry École Polytechnique Fédérale de Lausanne Lausanne Switzerland
- Computational Biomedicine, Institute of Neuroscience and Medicine (INM‐9)/Institute for Advanced Simulations (IAS‐5) Forschungszentrum Jülich Jülich Germany
| | - Giulia Rossetti
- Computational Biomedicine, Institute of Neuroscience and Medicine (INM‐9)/Institute for Advanced Simulations (IAS‐5) Forschungszentrum Jülich Jülich Germany
- Jülich Supercomputing Centre (JSC) Forschungszentrum Jülich Jülich Germany
- Department of Hematology, Oncology, Hemostaseology and Stem Cell Transplantation University Hospital Aachen RWTH Aachen University Aachen Germany
| | - Ursula Rothlisberger
- Laboratory of Computational Chemistry and Biochemistry École Polytechnique Fédérale de Lausanne Lausanne Switzerland
| | - Paolo Carloni
- Institute for Neuroscience and Medicine and Institute for Advanced Simulations (IAS‐5/INM‐9) “Computational Biomedicine” Forschungszentrum Jülich Jülich Germany
- JARA‐Institute INM‐11 “Molecular Neuroscience and Neuroimaging” Forschungszentrum Jülich Jülich Germany
| |
Collapse
|
4
|
Schein CH. Repurposing approved drugs on the pathway to novel therapies. Med Res Rev 2020; 40:586-605. [PMID: 31432544 PMCID: PMC7018532 DOI: 10.1002/med.21627] [Citation(s) in RCA: 42] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2019] [Revised: 07/17/2019] [Accepted: 07/26/2019] [Indexed: 12/22/2022]
Abstract
The time and cost of developing new drugs have led many groups to limit their search for therapeutics to compounds that have previously been approved for human use. Many "repurposed" drugs, such as derivatives of thalidomide, antibiotics, and antivirals have had clinical success in treatment areas well beyond their original approved use. These include applications in treating antibiotic-resistant organisms, viruses, cancers and to prevent burn scarring. The major theoretical justification for reusing approved drugs is that they have known modes of action and controllable side effects. Coadministering antibiotics with inhibitors of bacterial toxins or enzymes that mediate multidrug resistance can greatly enhance their activity. Drugs that control host cell pathways, including inflammation, tumor necrosis factor, interferons, and autophagy, can reduce the "cytokine storm" response to injury, control infection, and aid in cancer therapy. An active compound, even if previously approved for human use, will be a poor clinical candidate if it lacks specificity for the new target, has poor solubility or can cause serious side effects. Synergistic combinations can reduce the dosages of the individual components to lower reactivity. Preclinical analysis should take into account that severely ill patients with comorbidities will be more sensitive to side effects than healthy trial subjects. Once an active, approved drug has been identified, collaboration with medicinal chemists can aid in finding derivatives with better physicochemical properties, specificity, and efficacy, to provide novel therapies for cancers, emerging and rare diseases.
Collapse
Affiliation(s)
- Catherine H Schein
- Department of Biochemistry and Molecular Biology, Institute for Human Infection and Immunity (IHII), University of Texas Medical Branch at Galveston, Galveston, Texas
| |
Collapse
|
5
|
Affiliation(s)
- Megan Garland
- Cancer
Biology Program, ‡Department of Pathology, §Department of Microbiology and Immunology, and ∥Department of
Chemical and Systems Biology, Stanford University School of Medicine, 300 Pasteur Drive, Stanford, California 94305, United States
| | - Sebastian Loscher
- Cancer
Biology Program, ‡Department of Pathology, §Department of Microbiology and Immunology, and ∥Department of
Chemical and Systems Biology, Stanford University School of Medicine, 300 Pasteur Drive, Stanford, California 94305, United States
| | - Matthew Bogyo
- Cancer
Biology Program, ‡Department of Pathology, §Department of Microbiology and Immunology, and ∥Department of
Chemical and Systems Biology, Stanford University School of Medicine, 300 Pasteur Drive, Stanford, California 94305, United States
| |
Collapse
|
6
|
Schein CH, Rowold D, Choi KH. Allosteric inhibitors of Coxsackie virus A24 RNA polymerase. Bioorg Med Chem 2016; 24:570-7. [PMID: 26762834 PMCID: PMC4743507 DOI: 10.1016/j.bmc.2015.12.023] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2015] [Revised: 12/04/2015] [Accepted: 12/14/2015] [Indexed: 10/22/2022]
Abstract
Coxsackie virus A24 (CVA24), a causative agent of acute hemorrhagic conjunctivitis, is a prototype of enterovirus (EV) species C. The RNA polymerase (3D(pol)) of CVA24 can uridylylate the viral peptide linked to the genome (VPg) from distantly related EV and is thus, a good model for studying this reaction. Once UMP is bound, VPgpU primes RNA elongation. Structural and mutation data have identified a conserved binding surface for VPg on the RNA polymerase (3D(pol)), located about 20Å from the active site. Here, computational docking of over 60,000 small compounds was used to select those with the lowest (best) specific binding energies (BE) for this allosteric site. Compounds with varying structures and low BE were assayed for their effect on formation of VPgU by CVA24-3D(pol). Two compounds with the lowest specific BE for the site inhibited both uridylylation and formation of VPgpolyU at 10-20μM. These small molecules can be used to probe the role of this allosteric site in polymerase function, and may be the basis for novel antiviral compounds.
Collapse
Affiliation(s)
- Catherine H Schein
- Foundation for Applied Molecular Evolution, 13709 Progress Blvd, Box 7, Alachua, FL 32616, United States; Department of Biochemistry and Molecular Biology, University of Texas Medical Branch, Galveston, TX 77555, United States.
| | - Diane Rowold
- Foundation for Applied Molecular Evolution, 13709 Progress Blvd, Box 7, Alachua, FL 32616, United States
| | - Kyung H Choi
- Department of Biochemistry and Molecular Biology, University of Texas Medical Branch, Galveston, TX 77555, United States; Sealy Center for Structural Biology and Molecular Biophysics, UTMB, United States
| |
Collapse
|
7
|
Abstract
Anthrax is caused by the spore-forming, gram-positive bacterium Bacillus anthracis. The bacterium's major virulence factors are (a) the anthrax toxins and (b) an antiphagocytic polyglutamic capsule. These are encoded by two large plasmids, the former by pXO1 and the latter by pXO2. The expression of both is controlled by the bicarbonate-responsive transcriptional regulator, AtxA. The anthrax toxins are three polypeptides-protective antigen (PA), lethal factor (LF), and edema factor (EF)-that come together in binary combinations to form lethal toxin and edema toxin. PA binds to cellular receptors to translocate LF (a protease) and EF (an adenylate cyclase) into cells. The toxins alter cell signaling pathways in the host to interfere with innate immune responses in early stages of infection and to induce vascular collapse at late stages. This review focuses on the role of anthrax toxins in pathogenesis. Other virulence determinants, as well as vaccines and therapeutics, are briefly discussed.
Collapse
Affiliation(s)
- Mahtab Moayeri
- Microbial Pathogenesis Section, Laboratory of Parasitic Diseases, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland 20892; , , , ,
| | - Stephen H Leppla
- Microbial Pathogenesis Section, Laboratory of Parasitic Diseases, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland 20892; , , , ,
| | - Catherine Vrentas
- Microbial Pathogenesis Section, Laboratory of Parasitic Diseases, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland 20892; , , , ,
| | - Andrei P Pomerantsev
- Microbial Pathogenesis Section, Laboratory of Parasitic Diseases, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland 20892; , , , ,
| | - Shihui Liu
- Microbial Pathogenesis Section, Laboratory of Parasitic Diseases, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland 20892; , , , ,
| |
Collapse
|
8
|
Ohanjanian L, Remy KE, Li Y, Cui X, Eichacker PQ. An overview of investigational toxin-directed therapies for the adjunctive management of Bacillus anthracis infection and sepsis. Expert Opin Investig Drugs 2015; 24:851-65. [PMID: 25920540 DOI: 10.1517/13543784.2015.1041587] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
INTRODUCTION Sepsis with Bacillus anthracis infection has a very high mortality rate despite appropriate antibiotic and supportive therapies. Over the past 15 years, recent outbreaks in the US and in Europe, coupled with anthrax's bioterrorism weapon potential, have stimulated efforts to develop adjunctive therapies to improve clinical outcomes. Since lethal toxin and edema toxin (LT and ET) make central contributions to the pathogenesis of B. anthracis, these have been major targets in this effort. AREAS COVERED Here, the authors review different investigative biopharmaceuticals that have been recently identified for their therapeutic potential as inhibitors of LT or ET. Among these inhibitors are two antibody preparations that have been included in the Strategic National Stockpile (SNS) and several more that have reached Phase I testing. Presently, however, many of these candidate agents have only been studied in vitro and very few tested in bacteria-challenged models. EXPERT OPINION Although a large number of drugs have been identified as potential therapeutic inhibitors of LT and ET, in most cases their testing has been limited. The use of the two SNS antibody therapies during a large-scale exposure to B. anthracis will be difficult. Further testing and development of agents with oral bioavailability and relatively long shelf lives should be a focus for future research.
Collapse
Affiliation(s)
- Lernik Ohanjanian
- National Institutes of Health, Clinical Center, Critical Care Medicine Department , Building 10, Room 2C145, Bethesda, MD 20892 , USA +1 301 402 2914 ; +1 301 402 1213 ;
| | | | | | | | | |
Collapse
|
9
|
In Silico Genomic Fingerprints of the Bacillus anthracis Group Obtained by Virtual Hybridization. MICROARRAYS 2015; 4:84-97. [PMID: 27600214 PMCID: PMC4996382 DOI: 10.3390/microarrays4010084] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/21/2014] [Revised: 02/12/2015] [Accepted: 02/13/2015] [Indexed: 11/17/2022]
Abstract
In this study we evaluate the capacity of Virtual Hybridization to identify between highly related bacterial strains. Eight genomic fingerprints were obtained by virtual hybridization for the Bacillus anthracis genome set, and a set of 15,264 13-nucleotide short probes designed to produce genomic fingerprints unique for each organism. The data obtained from each genomic fingerprint were used to obtain hybridization patterns simulating a DNA microarray. Two virtual hybridization methods were used: the Direct and the Extended method to identify the number of potential hybridization sites and thus determine the minimum sensitivity value to discriminate between genomes with 99.9% similarity. Genomic fingerprints were compared using both methods and phylogenomic trees were constructed to verify that the minimum detection value is 0.000017. Results obtained from the genomic fingerprints suggest that the distribution in the trees is correct, as compared to other taxonomic methods. Specific virtual hybridization sites for each of the genomes studied were also identified.
Collapse
|
10
|
|
11
|
Abstract
INTRODUCTION Present-day rational drug design approaches are based on exploiting unique features of the target biomolecules, small- or macromolecule drug candidates and physical forces that govern their interactions. The 2013 Nobel Prize in chemistry awarded 'for the development of multiscale models for complex chemical systems' once again demonstrated the importance of the tailored drug discovery that reduces the role of the trial-and-error approach to a minimum. The intentional dissemination of Bacillus anthracis spores in 2001 via the so-called anthrax letters has led to increased efforts, politically and scientifically, to develop medical countermeasures that will protect people from the threat of anthrax bioterrorism. AREAS COVERED This article provides an overview of the recent rational drug design approaches for discovering inhibitors of anthrax toxin. The review also directs the readers to the vast literature on the recognized advances and future possibilities in the field. EXPERT OPINION Existing options to combat anthrax toxin lethality are limited. With the only anthrax toxin inhibiting therapy (protective antigen-targeting with a monoclonal antibody, raxibacumab) approved to treat inhalational anthrax, the situation, in our view, is still insecure. Further, the FDA's animal rule for drug approval, which clears compounds without validated efficacy studies on humans, creates a high level of uncertainty, especially when a well-characterized animal model does not exist. Better identification and validation of anthrax toxin therapeutic targets at the molecular level as well as elucidation of the parameters determining the corresponding therapeutic windows are still necessary for more effective therapeutic options.
Collapse
Affiliation(s)
- Ekaterina M Nestorovich
- The Catholic University of America, Department of Biology , Washington, DC , USA +1 202 319 6723 ;
| | | |
Collapse
|
12
|
Abstract
Computer-aided drug discovery/design methods have played a major role in the development of therapeutically important small molecules for over three decades. These methods are broadly classified as either structure-based or ligand-based methods. Structure-based methods are in principle analogous to high-throughput screening in that both target and ligand structure information is imperative. Structure-based approaches include ligand docking, pharmacophore, and ligand design methods. The article discusses theory behind the most important methods and recent successful applications. Ligand-based methods use only ligand information for predicting activity depending on its similarity/dissimilarity to previously known active ligands. We review widely used ligand-based methods such as ligand-based pharmacophores, molecular descriptors, and quantitative structure-activity relationships. In addition, important tools such as target/ligand data bases, homology modeling, ligand fingerprint methods, etc., necessary for successful implementation of various computer-aided drug discovery/design methods in a drug discovery campaign are discussed. Finally, computational methods for toxicity prediction and optimization for favorable physiologic properties are discussed with successful examples from literature.
Collapse
Affiliation(s)
- Gregory Sliwoski
- Jr., Center for Structural Biology, 465 21st Ave South, BIOSCI/MRBIII, Room 5144A, Nashville, TN 37232-8725.
| | | | | | | |
Collapse
|
13
|
Seifert R, Dove S. Inhibitors of Bacillus anthracis edema factor. Pharmacol Ther 2013; 140:200-12. [PMID: 23850654 DOI: 10.1016/j.pharmthera.2013.07.002] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2013] [Accepted: 06/17/2013] [Indexed: 01/09/2023]
Abstract
Edema factor (EF) is a calmodulin (CaM)-activated adenylyl cyclase (AC) toxin from Bacillus anthracis that contributes to anthrax pathogenesis. Anthrax is an important medical problem, but treatment of B. anthracis infections is still unsatisfying. Thus, selective EF inhibitors could be valuable drugs in the treatment of anthrax infection, most importantly shock. The catalytic site of EF, the EF/CaM interaction site and allosteric sites constitute potential drug targets. To this end, most efforts have been directed towards targeting the catalytic site. A major challenge in the field is to obtain compounds with high selectivity for AC toxins relative to mammalian membranous ACs (mACs). 3'-(N-methyl)anthraniloyl-2'-deoxyadenosine-5'-triphosphate is the most potent EF inhibitor known so far (Ki, 10nM), but selectivity relative to mACs needs to be improved (currently ~5-50-fold, depending on the specific mAC isoform considered). AC toxin inhibitors can be identified in virtual screening studies based on available EF crystal structures and examined in cellular test systems or at the level of purified toxin using classic radioisotopic or non-radioactive fluorescence assays. Binding of certain MANT-nucleotides to AC toxins elicits large direct fluorescence- or fluorescence resonance energy transfer signals upon interaction with CaM, and these signals can be used to identify toxin inhibitors in competition binding studies. Collectively, potent EF inhibitors are available, but before they can be used clinically, selectivity against mACs must be improved. However, several methodological approaches, complementing each other, are now available to direct the development of potent, selective, orally applicable and clinically useful EF inhibitors.
Collapse
Affiliation(s)
- Roland Seifert
- Institute of Pharmacology, Medical School of Hannover, Carl-Neuberg-Str. 1, D-30625 Hannover, Germany.
| | | |
Collapse
|
14
|
Abstract
Antibiotic treatment may fail to protect individuals, if not started early enough, after infection with Bacillus anthracis, due to the continuing activity of toxins that the bacterium produces. Stable and easily stored inhibitors of the edema factor toxin (EF), an adenylyl cyclase, could save lives in the event of an outbreak, due to natural causes or a bioweapon attack. The toxin’s basic activity is to convert ATP to cAMP, and it is thus in principle a simple phosphatase, which means that many mammalian enzymes, including intracellular adenylcyclases, may have a similar activity. While nucleotide based inhibitors, similar to its natural substrate, ATP, were identified early, these compounds had low activity and specificity for EF. We used a combined structural and computational approach to choose small organic molecules in large, web-based compound libraries that would, based on docking scores, bind to residues within the substrate binding pocket of EF. A family of fluorenone-based inhibitors was identified that inhibited the release of cAMP from cells treated with EF. The lead inhibitor was also shown to inhibit the diarrhea caused by enterotoxigenic E. coli (ETEC) in a murine model, perhaps by serving as a quorum sensor. These inhibitors are now being tested for their ability to inhibit Anthrax infection in animal models and may have use against other pathogens that produce toxins similar to EF, such as Bordetella pertussis or Vibrio cholera.
Collapse
|
15
|
Laine É, Martínez L, Ladant D, Malliavin T, Blondel A. Molecular motions as a drug target: mechanistic simulations of anthrax toxin edema factor function led to the discovery of novel allosteric inhibitors. Toxins (Basel) 2012; 4:580-604. [PMID: 23012649 PMCID: PMC3446745 DOI: 10.3390/toxins4080580] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2012] [Revised: 07/04/2012] [Accepted: 07/18/2012] [Indexed: 01/14/2023] Open
Abstract
Edema Factor (EF) is a component of Bacillus anthracis toxin essential for virulence. Its adenylyl cyclase activity is induced by complexation with the ubiquitous eukaryotic cellular protein, calmodulin (CaM). EF and its complexes with CaM, nucleotides and/or ions, have been extensively characterized by X-ray crystallography. Those structural data allowed molecular simulations analysis of various aspects of EF action mechanism, including the delineation of EF and CaM domains through their association energetics, the impact of calcium binding on CaM, and the role of catalytic site ions. Furthermore, a transition path connecting the free inactive form to the CaM-complexed active form of EF was built to model the activation mechanism in an attempt to define an inhibition strategy. The cavities at the surface of EF were determined for each path intermediate to identify potential sites where the binding of a ligand could block activation. A non-catalytic cavity (allosteric) was found to shrink rapidly at early stages of the path and was chosen to perform virtual screening. Amongst 18 compounds selected in silico and tested in an enzymatic assay, 6 thiophen ureidoacid derivatives formed a new family of EF allosteric inhibitors with IC50 as low as 2 micromolars.
Collapse
Affiliation(s)
- Élodie Laine
- Laboratoire de Biologie et de Pharmacologie Appliquée, Ecole Normale Supérieure de Cachan, 61, avenue du Président Wilson, 94235 Cachan cedex, France;
| | - Leandro Martínez
- The Molecular Biotechnology Group, Institute of Physics of São Carlos, University of São Paulo, Av. Trabalhador Sãocarlense, 400, 13566-590 São Carlos, SP, Brazil;
| | - Daniel Ladant
- Unité de Biochimie des Interactions Macromoléculaires and CNRS UMR 3528, Département de Biologie Structurale et Chimie, Institut Pasteur, 28, rue du Dr. Roux, 75724 Paris Cedex 15, France;
| | - Thérèse Malliavin
- Unité de Bioinformatique Structurale and CNRS UMR 3528, Département de Biologie Structurale et Chimie, Institut Pasteur, 25, rue du Dr. Roux, 75724 Paris Cedex 15, France;
| | - Arnaud Blondel
- Unité de Bioinformatique Structurale and CNRS UMR 3528, Département de Biologie Structurale et Chimie, Institut Pasteur, 25, rue du Dr. Roux, 75724 Paris Cedex 15, France;
| |
Collapse
|
16
|
Ivarsson ME, Leroux JC, Castagner B. Targeting bacterial toxins. Angew Chem Int Ed Engl 2012; 51:4024-45. [PMID: 22441768 DOI: 10.1002/anie.201104384] [Citation(s) in RCA: 51] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2011] [Revised: 09/21/2011] [Indexed: 12/18/2022]
Abstract
Protein toxins constitute the main virulence factors of several species of bacteria and have proven to be attractive targets for drug development. Lead candidates that target bacterial toxins range from small molecules to polymeric binders, and act at each of the multiple steps in the process of toxin-mediated pathogenicity. Despite recent and significant advances in the field, a rationally designed drug that targets toxins has yet to reach the market. This Review presents the state of the art in bacterial toxin targeted drug development with a critical consideration of achieved breakthroughs and withstanding challenges. The discussion focuses on A-B-type protein toxins secreted by four species of bacteria, namely Clostridium difficile (toxins A and B), Vibrio cholerae (cholera toxin), enterohemorrhagic Escherichia coli (Shiga toxin), and Bacillus anthracis (anthrax toxin), which are the causative agents of diseases for which treatments need to be improved.
Collapse
Affiliation(s)
- Mattias E Ivarsson
- Institute of Pharmaceutical Sciences, Swiss Federal Institute of Technology Zurich, Wolfgang-Pauli-Strasse 10, Zurich, Switzerland
| | | | | |
Collapse
|
17
|
|
18
|
Chen D, Ma L, Kanalas JJ, Gao J, Pawlik J, Jimenez ME, Walter MA, Peterson JW, Gilbertson SR, Schein CH. Structure-based redesign of an edema toxin inhibitor. Bioorg Med Chem 2012; 20:368-76. [PMID: 22154558 PMCID: PMC3251925 DOI: 10.1016/j.bmc.2011.10.091] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2011] [Revised: 10/17/2011] [Accepted: 10/25/2011] [Indexed: 11/17/2022]
Abstract
Edema factor (EF) toxin of Bacillus anthracis (NIAID category A), and several other toxins from NIAID category B Biodefense target bacteria are adenylyl cyclases or adenylyl cyclase agonists that catalyze the conversion of ATP to 3',5'-cyclic adenosine monophosphate (cAMP). We previously identified compound 1 (3-[(9-oxo-9H-fluorene-1-carbonyl)-amino]-benzoic acid), that inhibits EF activity in cultured mammalian cells, and reduces diarrhea caused by enterotoxigenic Escherichia coli (ETEC) at an oral dosage of 15μg/mouse. Here, molecular docking was used to predict improvements in potency and solubility of new derivatives of compound 1 in inhibiting edema toxin (ET)-catalyzed stimulation of cyclic AMP production in murine monocyte-macrophage cells (RAW 264.7). Structure-activity relationship (SAR) analysis of the bioassay results for 22 compounds indicated positions important for activity. Several derivatives demonstrated superior pharmacological properties compared to our initial lead compound, and are promising candidates to treat anthrax infections and diarrheal diseases induced by toxin-producing bacteria.
Collapse
Affiliation(s)
- Deliang Chen
- Sealy Center for Structural Biology and Molecular Biophysics, Department of Biochemistry and Molecular Biology, UTMB, Galveston, TX 77555-0857, USA
| | - Lili Ma
- Department of Chemistry, University of Houston. Houston, TX 77004, USA
| | | | - Jian Gao
- Mission Pharmacal Company, San Antonio, TX USA
| | - Jennifer Pawlik
- Sealy Center for Vaccine Development, Center for Biodefense and Emerging Infections, UTMB, Galveston, TX 77555, USA
- Department of Microbiology and Immunology, UTMB, Galveston, TX 77555-1070, USA
| | | | | | - Johnny W. Peterson
- Sealy Center for Vaccine Development, Center for Biodefense and Emerging Infections, UTMB, Galveston, TX 77555, USA
- Department of Microbiology and Immunology, UTMB, Galveston, TX 77555-1070, USA
| | | | - Catherine H. Schein
- Sealy Center for Structural Biology and Molecular Biophysics, Department of Biochemistry and Molecular Biology, UTMB, Galveston, TX 77555-0857, USA
- Sealy Center for Vaccine Development, Center for Biodefense and Emerging Infections, UTMB, Galveston, TX 77555, USA
- Department of Microbiology and Immunology, UTMB, Galveston, TX 77555-1070, USA
- Member, Institute for Translational Studies, UTMB
| |
Collapse
|
19
|
Makiya M, Dolan M, Agulto L, Purcell R, Chen Z. Structural basis of anthrax edema factor neutralization by a neutralizing antibody. Biochem Biophys Res Commun 2011; 417:324-9. [PMID: 22155239 DOI: 10.1016/j.bbrc.2011.11.108] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2011] [Accepted: 11/19/2011] [Indexed: 11/16/2022]
Abstract
Fine epitope mapping of EF13D, a highly potent neutralizing monoclonal antibody specific for the anthrax edema factor (EF), was accomplished through random mutagenesis and yeast surface display. A yeast-displayed library of single point mutants of an EF domain III (DIII), comprising amino acids 624-800, was constructed by random mutagenesis and screened for reduced binding to EF13D. With this method, residues Leu 667, Ser 668, Arg 671, and Arg 672 were identified as key residues important for EF13D binding. They form a contiguous patch on a solvent-exposed surface at one end of the four-helix bundle of DIII. Computational protein-protein docking experiments between anEF13D model and a crystal structure of EF indicate that the EF13D heavy chain complementarity-determining region 3 (HCDR3) is deeply buried within a hydrophobic cleft between two helices of DIII and interacts directly with residues Leu 667, Ser 668, Arg 671 and Arg 672, providing an explanation for the high binding affinity. In addition, they show that the HCDR3 binding site overlaps with the binding site of the N-terminal lobe of calmodulin (CaM), an EF enzymatic activator, consistent with a previous finding showing direct competition with CaM that results in neutralization of EF. Identifying the neutralization epitope of EF13D on EF improves our understanding of the neutralization mechanism and has implications for vaccine development.
Collapse
Affiliation(s)
- Michelle Makiya
- Laboratory of Infectious Diseases, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD 20892, United States
| | | | | | | | | |
Collapse
|
20
|
Abstract
Fragment-based design has significantly modified drug discovery strategies and paradigms in the last decade. Besides technological advances and novel therapeutic avenues, one of the most significant changes brought by this new discipline has occurred in the minds of drug designers. Fragment-based approaches have markedly impacted rational computer-aided design both in method development and in applications. The present review illustrates the importance of molecular fragments in many aspects of rational ligand design, and discusses how thinking in "fragment space" has boosted computational biology and chemistry.
Collapse
|
21
|
Lee JS, White E, Kim SG, Kim SK. Virtual Screening of Penicillin-derived Inhibitors for the Metallo-β-lactamase from Bacillus cereus. B KOREAN CHEM SOC 2010. [DOI: 10.5012/bkcs.2010.31.12.3644] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
|
22
|
Bouzianas DG. Current and future medical approaches to combat the anthrax threat. J Med Chem 2010; 53:4305-31. [PMID: 20102155 DOI: 10.1021/jm901024b] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Affiliation(s)
- Dimitrios G Bouzianas
- Laboratory of Molecular Endocrinology, Division of Endocrinology and Metabolism, AHEPA University Hospital, 1 S. Kyriakidi Street, P.C. 54636, Thessaloniki, Macedonia, Greece.
| |
Collapse
|
23
|
Use of allostery to identify inhibitors of calmodulin-induced activation of Bacillus anthracis edema factor. Proc Natl Acad Sci U S A 2010; 107:11277-82. [PMID: 20534570 DOI: 10.1073/pnas.0914611107] [Citation(s) in RCA: 55] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023] Open
Abstract
Allostery plays a key role in the regulation of the activity and function of many biomolecules. And although many ligands act through allostery, no systematic use is made of it in drug design strategies. Here we describe a procedure for identifying the regions of a protein that can be used to control its activity through allostery. This procedure is based on the construction of a plausible conformational path, which describes protein transition between known active and inactive conformations. The path is calculated by using a framework approach that steers and markedly improves the conjugate peak refinement method. The evolution of conformations along this path was used to identify a putative allosteric site that could regulate activation of Bacillus anthracis adenylyl cyclase toxin (EF) by calmodulin. Conformations of the allosteric site at different steps along the path from the inactive (free) to the active (bound to calmodulin) forms of EF were used to perform virtual screenings and propose candidate EF inhibitors. Several candidates then proved to inhibit calmodulin-induced activation in an in vitro assay. The most potent compound fully inhibited EF at a concentration of 10 microM. The compounds also inhibited the related adenylyl cyclase toxin from Bordetella pertussis (CyaA). The specific homology between the putative allosteric sites in both toxins supports that these pockets are the actual binding sites of the selected inhibitors.
Collapse
|
24
|
Testing the efficacy and toxicity of adenylyl cyclase inhibitors against enteric pathogens using in vitro and in vivo models of infection. Infect Immun 2010; 78:1740-9. [PMID: 20123712 DOI: 10.1128/iai.01114-09] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Enterotoxigenic Escherichia coli (ETEC) produces the ADP-ribosyltransferase toxin known as heat-labile enterotoxin (LT). In addition to the toxic effect of LT resulting in increases of cyclic AMP (cAMP) and disturbance of cellular metabolic processes, this toxin promotes bacterial adherence to intestinal epithelial cells (A. M. Johnson, R. S. Kaushik, D. H. Francis, J. M. Fleckenstein, and P. R. Hardwidge, J. Bacteriol. 191:178-186, 2009). Therefore, we hypothesized that the identification of a compound that inhibits the activity of the toxin would have a suppressive effect on the ETEC colonization capabilities. Using in vivo and in vitro approaches, we present evidence demonstrating that a fluorenone-based compound, DC5, which inhibits the accumulation of cAMP in intoxicated cultured cells, significantly decreases the colonization abilities of adenylyl cyclase toxin-producing bacteria, such as ETEC. These findings established that DC5 is a potent inhibitor both of toxin-induced cAMP accumulation and of ETEC adherence to epithelial cells. Thus, DC5 may be a promising compound for treatment of diarrhea caused by ETEC and other adenylyl cyclase toxin-producing bacteria.
Collapse
|
25
|
Neuhaus FC. Role of Arg301 in substrate orientation and catalysis in subsite 2 of D-alanine:D-alanine (D-lactate) ligase from Leuconostoc mesenteroides: a molecular docking study. J Mol Graph Model 2010; 28:728-34. [PMID: 20167520 DOI: 10.1016/j.jmgm.2010.01.010] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2009] [Accepted: 01/22/2010] [Indexed: 11/27/2022]
Abstract
D-alanine:D-alanine (D-lactate) ligase (ADP) from Leuconostoc mesenteroides synthesizes the depsipeptide, D-alanyl-D-lactate, in addition to D-alanyl-D-alanine, when D-alanine and D-lactate are incubated simultaneously. The depsipeptide is responsible for the intrinsic resistance of this organism to vancomycin. The orientations of D-lactate and D-alanine in subsite 2 of the ligase that result in both nucleophile generation and subsequent attack on the electrophilic center of D-alanyl phosphate in subsite 1 are not known. A molecular docking study using AutoDock 4 suggests a role for Arg301 in determining these orientations of acceptor substrate in subsite 2 for both nucleophile generation and subsequent attack on the phosphate intermediate. With D-lactate a bifurcated H-bond from Arg301 to the R-OH of D-lactate may account for its orientation and nucleophile activation. This orientation is observed when the guanidino side chain of this residue is flexible. D-alanine adopts an orientation that utilizes H-bonding to water 2882 and the D-alanyl phosphate in subsite 1. Both of these orientations provide mechanisms of deprotonation and place the nucleophile within 3.2A of the electrophilic carbonyl of the D-alanyl phosphate intermediate for formation of the transition state. These results suggest that Arg301 has a dual function in a sequential reaction mechanism, i.e. substrate orientation in subsite 2 as well as stabilization of the transition state. In addition, these docking studies provide insights for inhibitor design targeted to this subsite of the ligase.
Collapse
Affiliation(s)
- Francis C Neuhaus
- Department of Biochemistry, 2205 Tech Drive, Northwestern University, Evanston, IL 60208-3500, USA.
| |
Collapse
|
26
|
Janowiak BE, Fischer A, Collier RJ. Effects of introducing a single charged residue into the phenylalanine clamp of multimeric anthrax protective antigen. J Biol Chem 2010; 285:8130-7. [PMID: 20061382 DOI: 10.1074/jbc.m109.093195] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Multimeric pores formed in the endosomal membrane by the Protective Antigen moiety of anthrax toxin translocate the enzymatic moieties of the toxin to the cytosolic compartment of mammalian cells. There is evidence that the side chains of the Phe(427) residues come into close proximity with one another in the lumen of the pore and form a structure, termed the Phe clamp, that catalyzes the translocation process. In this report we describe the effects of replacing Phe(427) in a single subunit of the predominantly heptameric pore with a basic or an acidic amino acid. Incorporating any charged residue at this position inhibited cytotoxicity >or=1,000-fold in our standard assay and caused strong inhibition of translocation in a planar phospholipid bilayer system. His and Glu were the most strongly inhibitory residues, ablating both cytotoxicity and translocation. Basic residues at position 427 prevented the Phe clamp from interacting with a translocation substrate to form a seal against the passage of ions and accelerated dissociation of the substrate from the pore. Acidic residues, in contrast, allowed the seal to form and the substrate to remain firmly bound, but blocked its passage, perhaps via electrostatic interactions with the positively charged N-terminal segment. Our findings are discussed in relation to the role of the Phe clamp in a Brownian ratchet model of translocation.
Collapse
Affiliation(s)
- Blythe E Janowiak
- Department of Microbiology and Molecular Genetics, Harvard Medical School, Boston, Massachusetts 02115, USA
| | | | | |
Collapse
|
27
|
Kolb P, Ferreira RS, Irwin JJ, Shoichet BK. Docking and chemoinformatic screens for new ligands and targets. Curr Opin Biotechnol 2009; 20:429-36. [PMID: 19733475 DOI: 10.1016/j.copbio.2009.08.003] [Citation(s) in RCA: 133] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2009] [Accepted: 08/05/2009] [Indexed: 12/13/2022]
Abstract
Computer-based docking screens are now widely used to discover new ligands for targets of known structure; in the last two years alone, the discovery of ligands for more than 20 proteins has been reported. Recently, investigators have also turned to predicting new substrates for enzymes of unknown function, taking docking in a wholly new direction. Increasingly, the hit rates, the true-positives, and the false-positives from the docking screens are being compared to those from empirical, high-throughput screens, revealing the strengths, weaknesses, and complementarities of both techniques. The recent efflorescence of GPCR structures has made these quintessential drug targets available to structure-based approaches. Consistent with their 'druggability', the docking screens have returned high hit rates and potent molecules. Finally, in the last several years, an approach almost exactly opposite to docking has also appeared; this pharmacological network approach begins not with the structure of the target but rather those of drug molecules and asks, given a pattern of chemistry in the ligands, what targets may a particular drug bind to? This method, which returns to an older, pharmacology logic, has been surprisingly successful in predicting new 'off-targets' for established drugs.
Collapse
Affiliation(s)
- Peter Kolb
- Dept of Pharmaceutical Chemistry, University of California, San Francisco, 1700 4th St., Byers Hall Room 508D, San Francisco, CA 94158-2550, United States
| | | | | | | |
Collapse
|
28
|
Chen D, Martin ZS, Soto C, Schein CH. Computational selection of inhibitors of Abeta aggregation and neuronal toxicity. Bioorg Med Chem 2009; 17:5189-97. [PMID: 19540126 PMCID: PMC2743868 DOI: 10.1016/j.bmc.2009.05.047] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2009] [Revised: 05/13/2009] [Accepted: 05/18/2009] [Indexed: 11/18/2022]
Abstract
Alzheimer's disease (AD) is characterized by the cerebral accumulation of misfolded and aggregated amyloid-beta protein (Abeta). Disease symptoms can be alleviated, in vitro and in vivo, by 'beta-sheet breaker' pentapeptides that reduce plaque load. However the peptide nature of these compounds, made them biologically unstable and unable to penetrate membranes with high efficiency. The main goal of this study was to use computational methods to identify small molecule mimetics with better drug-like properties. For this purpose, the docked conformations of the active peptides were used to identify compounds with similar activities. A series of related beta-sheet breaker peptides were docked to solid state NMR structures of a fibrillar form of Abeta. The lowest energy conformations of the active peptides were used to design three dimensional (3D)-pharmacophores, suitable for screening the NCI database with Unity. Small molecular weight compounds with physicochemical features and a conformation similar to the active peptides were selected, ranked by docking and biochemical parameters. Of 16 diverse compounds selected for experimental screening, 2 prevented and reversed Abeta aggregation at 2-3microM concentration, as measured by Thioflavin T (ThT) fluorescence and ELISA assays. They also prevented the toxic effects of aggregated Abeta on neuroblastoma cells. Their low molecular weight and aqueous solubility makes them promising lead compounds for treating AD.
Collapse
Affiliation(s)
- Deliang Chen
- Sealy Center for Structural Biology and Molecular Biophysics, Department of Biochemistry and Molecular Biology, UTMB, Galveston, TX 77555-0857, USA
| | - Zane S. Martin
- George and Cynthia Mitchell Center for Neurodegenerative diseases, Department of Neurology, Neurosciences & Cell Biology UTMB, Galveston TX 77555-1045, USA
| | - Claudio Soto
- George and Cynthia Mitchell Center for Neurodegenerative diseases, Department of Neurology, Neurosciences & Cell Biology UTMB, Galveston TX 77555-1045, USA
- Department of Neurology, University of Texas Medical School at Houston. Houston, TX 77030, USA
| | - Catherine H. Schein
- Sealy Center for Structural Biology and Molecular Biophysics, Department of Biochemistry and Molecular Biology, UTMB, Galveston, TX 77555-0857, USA
- Department of Microbiology and Immunology, and Sealy Center for Vaccine Development, UTMB, Galveston, TX 77555-0857, USA
| |
Collapse
|
29
|
Heng S, Gryncel KR, Kantrowitz ER. A library of novel allosteric inhibitors against fructose 1,6-bisphosphatase. Bioorg Med Chem 2009; 17:3916-22. [PMID: 19419876 DOI: 10.1016/j.bmc.2009.04.030] [Citation(s) in RCA: 61] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2009] [Revised: 04/07/2009] [Accepted: 04/09/2009] [Indexed: 10/20/2022]
Abstract
The identification of a proper lead compound for fructose 1,6-bisphosphatase (FBPase) is a critical step in the process of developing novel therapeutics against type-2 diabetes. Herein, we have successfully generated a library of allosteric inhibitors against FBPase as potential anti-diabetic drugs, of which, the lead compound 1b was identified through utilizing a virtual high-throughput screening (vHTS) system, which we have developed. The thiazole-based core structure was synthesized via the condensation of alpha-bromo-ketones with thioureas and substituents on the two aryl rings were varied. 4c was found to inhibit pig kidney FBPase approximately fivefold better than 1b. In addition, we have also identified 10b, a tight binding fragment, which can be use for fragment-based drug design purposes.
Collapse
Affiliation(s)
- Sabrina Heng
- Boston College, Department of Chemistry, Merkert Chemistry Center, Chestnut Hill, MA 02467, USA
| | | | | |
Collapse
|
30
|
Beckmann J, Hesse M. Reactivity of the Dinuclear Arylstibonic Acid [2,6-Mes2C6H3Sb(O)(OH)2]2 toward H2SO4 and NaOH. Organometallics 2009. [DOI: 10.1021/om900030m] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Affiliation(s)
- Jens Beckmann
- Institut für Chemie and Biochemie, Freie Universität Berlin, Fabeckstrasse 34-36, 14195 Berlin, Germany
| | - Malte Hesse
- Institut für Chemie and Biochemie, Freie Universität Berlin, Fabeckstrasse 34-36, 14195 Berlin, Germany
| |
Collapse
|