1
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Harden SA, Courbon GM, Liang Y, Kim AS, Rubinstein JL. A simple assay for inhibitors of mycobacterial oxidative phosphorylation. J Biol Chem 2024; 300:105483. [PMID: 37992805 PMCID: PMC10770618 DOI: 10.1016/j.jbc.2023.105483] [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] [Received: 08/08/2023] [Revised: 10/26/2023] [Accepted: 11/15/2023] [Indexed: 11/24/2023] Open
Abstract
Oxidative phosphorylation, the combined activities of the electron transport chain (ETC) and ATP synthase, has emerged as a valuable target for antibiotics to treat infection with Mycobacterium tuberculosis and related pathogens. In oxidative phosphorylation, the ETC establishes a transmembrane electrochemical proton gradient that powers ATP synthesis. Monitoring oxidative phosphorylation with luciferase-based detection of ATP synthesis or measurement of oxygen consumption can be technically challenging and expensive. These limitations reduce the utility of these methods for characterization of mycobacterial oxidative phosphorylation inhibitors. Here, we show that fluorescence-based measurement of acidification of inverted membrane vesicles (IMVs) can detect and distinguish between inhibition of the ETC, inhibition of ATP synthase, and nonspecific membrane uncoupling. In this assay, IMVs from Mycobacterium smegmatis are acidified either through the activity of the ETC or ATP synthase, the latter modified genetically to allow it to serve as an ATP-driven proton pump. Acidification is monitored by fluorescence from 9-amino-6-chloro-2-methoxyacridine, which accumulates and quenches in acidified IMVs. Nonspecific membrane uncouplers prevent both succinate- and ATP-driven IMV acidification. In contrast, the ETC Complex III2IV2 inhibitor telacebec (Q203) prevents succinate-driven acidification but not ATP-driven acidification, and the ATP synthase inhibitor bedaquiline prevents ATP-driven acidification but not succinate-driven acidification. We use the assay to show that, as proposed previously, lansoprazole sulfide is an inhibitor of Complex III2IV2, whereas thioridazine uncouples the mycobacterial membrane nonspecifically. Overall, the assay is simple, low cost, and scalable, which will make it useful for identifying and characterizing new mycobacterial oxidative phosphorylation inhibitors.
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Affiliation(s)
- Serena A Harden
- Molecular Medicine Program, The Hospital for Sick Children, Toronto, Ontario, Canada
| | - Gautier M Courbon
- Molecular Medicine Program, The Hospital for Sick Children, Toronto, Ontario, Canada; Department of Medical Biophysics, The University of Toronto, Toronto, Ontario, Canada
| | - Yingke Liang
- Molecular Medicine Program, The Hospital for Sick Children, Toronto, Ontario, Canada; Department of Biochemistry, The University of Toronto, Toronto, Ontario, Canada
| | - Angelina S Kim
- Molecular Medicine Program, The Hospital for Sick Children, Toronto, Ontario, Canada; Department of Biochemistry, The University of Toronto, Toronto, Ontario, Canada
| | - John L Rubinstein
- Molecular Medicine Program, The Hospital for Sick Children, Toronto, Ontario, Canada; Department of Medical Biophysics, The University of Toronto, Toronto, Ontario, Canada; Department of Biochemistry, The University of Toronto, Toronto, Ontario, Canada.
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2
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Verma M, Nisha A, Bathla M, Acharya A. Resveratrol-Encapsulated Glutathione-Modified Robust Mesoporous Silica Nanoparticles as an Antibacterial and Antibiofilm Coating Agent for Medical Devices. ACS APPLIED MATERIALS & INTERFACES 2023; 15:58212-58229. [PMID: 38060572 DOI: 10.1021/acsami.3c13733] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/22/2023]
Abstract
The emergence of various lethal bacterial infections and their adherence to medical devices are major public health concerns. The increased bacterial exposure and titer are accompanied by the inappropriate use of antibiotics that sometimes lead to antibiotic resistance, and therefore, a drug-free antibacterial approach is required. Several nanoparticles (NPs) have been developed as antibacterial and antibiofilm coating agents, which can overcome different drug resistance mechanisms by inhibiting the important processes related to bacterial virulence potential. However, developing safe and biocompatible nanomaterials (NMs) for these applications has remained a major challenge due to their poorly understood mechanism of action. In this work, biogenic silica NPs were modified with glutathione (GSH) to form GSH@SNP (∼80 ± 15 nm) for targeting the bacterial cell surface and biofilm. GSH@SNP was loaded with resveratrol to obtain Res_GSH@SNP (∼124 ± 15 nm) that enhances the antibacterial activity of the NPs against Staphylococcus aureus and Escherichia coli by ∼51 and ∼49%, respectively, compared to GSH@SNP. Res_GSH@SNP is responsible for binding to the bacterial cell surface receptors that interrupt the cell membrane potential, leading to reactive oxygen species (ROS) generation, membrane disruption, and DNA damage and eventually resulting in antibacterial activity. Moreover, the antibiofilm activity of Res_GSH@SNP has been found to result from the interaction of the NPs with the abundant carbohydrates present on the biofilm surface. To check the practical utility of Res_GSH@SNP, these were further evaluated as an antibacterial and antibiofilm coating agent for urinary catheters and were found to be effective even after multiple washes. Res_GSH@SNP has been found to exhibit ∼80 ± 1.4% cytocompatibility toward fibroblast NIH-3T3 cells. Overall, this study is expected to pave the way for the development of biocompatible NP-based coating agents for medical devices.
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Affiliation(s)
- Mohini Verma
- Biotechnology Division, CSIR-Institute of Himalayan Bioresource Technology, Palampur, Himachal Pradesh 176061, India
- Academy of Scientific & Innovative Research (AcSIR), Ghaziabad 201002, India
| | - Anjali Nisha
- Biotechnology Division, CSIR-Institute of Himalayan Bioresource Technology, Palampur, Himachal Pradesh 176061, India
- Academy of Scientific & Innovative Research (AcSIR), Ghaziabad 201002, India
| | - Manik Bathla
- Biotechnology Division, CSIR-Institute of Himalayan Bioresource Technology, Palampur, Himachal Pradesh 176061, India
- Academy of Scientific & Innovative Research (AcSIR), Ghaziabad 201002, India
| | - Amitabha Acharya
- Biotechnology Division, CSIR-Institute of Himalayan Bioresource Technology, Palampur, Himachal Pradesh 176061, India
- Academy of Scientific & Innovative Research (AcSIR), Ghaziabad 201002, India
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3
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Ragunathan P, Shuyi Ng P, Singh S, Poh WH, Litty D, Kalia NP, Larsson S, Harikishore A, Rice SA, Ingham PW, Müller V, Moraski G, Miller MJ, Dick T, Pethe K, Grüber G. GaMF1.39's antibiotic efficacy and its enhanced antitubercular activity in combination with clofazimine, Telacebec, ND-011992, or TBAJ-876. Microbiol Spectr 2023; 11:e0228223. [PMID: 37982630 PMCID: PMC10715162 DOI: 10.1128/spectrum.02282-23] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2023] [Accepted: 10/12/2023] [Indexed: 11/21/2023] Open
Abstract
IMPORTANCE New drugs are needed to combat multidrug-resistant tuberculosis. The electron transport chain (ETC) maintains the electrochemical potential across the cytoplasmic membrane and allows the production of ATP, the energy currency of any living cell. The mycobacterial engine F-ATP synthase catalyzes the formation of ATP and has come into focus as an attractive and rich drug target. Recent deep insights into these mycobacterial F1FO-ATP synthase elements opened the door for a renaissance of structure-based target identification and inhibitor design. In this study, we present the GaMF1.39 antimycobacterial compound, targeting the rotary subunit γ of the biological engine. The compound is bactericidal, inhibits infection ex vivo, and displays enhanced anti-tuberculosis activity in combination with ETC inhibitors, which promises new strategies to shorten tuberculosis chemotherapy.
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Affiliation(s)
- Priya Ragunathan
- School of Biological Sciences, Nanyang Technological University, Singapore, Singapore
| | - Pearly Shuyi Ng
- Experimental Drug Development Centre, Agency for Science, Technology and Research, Singapore, Singapore
| | - Samsher Singh
- Lee Kong Chian School of Medicine, Nanyang Technological University, Experimental Medicine Building, Singapore, Singapore
| | - Wee Han Poh
- Singapore Centre for Environmental Life Sciences Engineering, Nanyang Technological University, Singapore, Singapore
| | - Dennis Litty
- Molecular Microbiology and Bioenergetics, Institute for Molecular Biosciences, Johann Wolfgang Goethe University Frankfurt/Main, Frankfurt, Germany
| | - Nitin Pal Kalia
- Department of Biological Sciences (Pharmacology & Toxicology), National Institute of Pharmaceutical Education and Research, Hyderabad, Telangana, India
| | - Simon Larsson
- Lee Kong Chian School of Medicine, Nanyang Technological University, Experimental Medicine Building, Singapore, Singapore
| | - Amaravadhi Harikishore
- School of Biological Sciences, Nanyang Technological University, Singapore, Singapore
- School of Chemistry, Chemical Engineering and Biotechnology, Nanyang Technological University, Singapore, Singapore
| | - Scott A. Rice
- School of Biological Sciences, Nanyang Technological University, Singapore, Singapore
- Singapore Centre for Environmental Life Sciences Engineering, Nanyang Technological University, Singapore, Singapore
| | - Philip W. Ingham
- Lee Kong Chian School of Medicine, Nanyang Technological University, Experimental Medicine Building, Singapore, Singapore
| | - Volker Müller
- Molecular Microbiology and Bioenergetics, Institute for Molecular Biosciences, Johann Wolfgang Goethe University Frankfurt/Main, Frankfurt, Germany
| | - Garrett Moraski
- Department of Chemistry and Biochemistry, Montana State University, Bozeman, Montana, USA
| | - Marvin J. Miller
- Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, Indiana, USA
| | - Thomas Dick
- Center for Discovery and Innovation, Hackensack Meridian Health, Nutley, New Jersey, USA
- Department of Medical Sciences, Hackensack Meridian School of Medicine, Nutley, New Jersey, USA
- Department of Microbiology and Immunology, Georgetown University, Washington, DC, USA
| | - Kevin Pethe
- School of Biological Sciences, Nanyang Technological University, Singapore, Singapore
- Lee Kong Chian School of Medicine, Nanyang Technological University, Experimental Medicine Building, Singapore, Singapore
- National Centre for Infectious Diseases (NCID), Jalan Tan Tock Seng, Singapore, Singapore
| | - Gerhard Grüber
- School of Biological Sciences, Nanyang Technological University, Singapore, Singapore
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4
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Saw WG, Le KCM, Shin J, Kwek JHM, Wong CF, Ragunathan P, Fong TC, Müller V, Grüber G. Atomic insights of an up and down conformation of the Acinetobacter baumannii F 1 -ATPase subunit ε and deciphering the residues critical for ATP hydrolysis inhibition and ATP synthesis. FASEB J 2023; 37:e23040. [PMID: 37318822 DOI: 10.1096/fj.202300175rr] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2023] [Revised: 05/23/2023] [Accepted: 06/05/2023] [Indexed: 06/16/2023]
Abstract
The Acinetobacter baumannii F1 FO -ATP synthase (α3 :β3 :γ:δ:ε:a:b2 :c10 ), which is essential for this strictly respiratory opportunistic human pathogen, is incapable of ATP-driven proton translocation due to its latent ATPase activity. Here, we generated and purified the first recombinant A. baumannii F1 -ATPase (AbF1 -ATPase) composed of subunits α3 :β3 :γ:ε, showing latent ATP hydrolysis. A 3.0 Å cryo-electron microscopy structure visualizes the architecture and regulatory element of this enzyme, in which the C-terminal domain of subunit ε (Abε) is present in an extended position. An ε-free AbF1 -ɑβγ complex generated showed a 21.5-fold ATP hydrolysis increase, demonstrating that Abε is the major regulator of AbF1 -ATPase's latent ATP hydrolysis. The recombinant system enabled mutational studies of single amino acid substitutions within Abε or its interacting subunits β and γ, respectively, as well as C-terminal truncated mutants of Abε, providing a detailed picture of Abε's main element for the self-inhibition mechanism of ATP hydrolysis. Using a heterologous expression system, the importance of Abε's C-terminus in ATP synthesis of inverted membrane vesicles, including AbF1 FO -ATP synthases, has been explored. In addition, we are presenting the first NMR solution structure of the compact form of Abε, revealing interaction of its N-terminal β-barrel and C-terminal ɑ-hairpin domain. A double mutant of Abε highlights critical residues for Abε's domain-domain formation which is important also for AbF1 -ATPase's stability. Abε does not bind MgATP, which is described to regulate the up and down movements in other bacterial counterparts. The data are compared to regulatory elements of F1 -ATPases in bacteria, chloroplasts, and mitochondria to prevent wasting of ATP.
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Affiliation(s)
- Wuan-Geok Saw
- School of Biological Sciences, Nanyang Technological University, Singapore, Singapore
- NTU Institute of Structural Biology, Nanyang Technological University, Singapore, Singapore
| | - Khoa Cong Minh Le
- School of Biological Sciences, Nanyang Technological University, Singapore, Singapore
| | - Joon Shin
- School of Biological Sciences, Nanyang Technological University, Singapore, Singapore
| | - Jes Hui Min Kwek
- School of Biological Sciences, Nanyang Technological University, Singapore, Singapore
| | - Chui Fann Wong
- School of Biological Sciences, Nanyang Technological University, Singapore, Singapore
| | - Priya Ragunathan
- School of Biological Sciences, Nanyang Technological University, Singapore, Singapore
| | - Tuck Choy Fong
- School of Biological Sciences, Nanyang Technological University, Singapore, Singapore
| | - Volker Müller
- Institute of Molecular Biosciences, Johann Wolfgang Goethe University, Frankfurt, Germany
| | - Gerhard Grüber
- School of Biological Sciences, Nanyang Technological University, Singapore, Singapore
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5
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Mackieh R, Al-Bakkar N, Kfoury M, Roufayel R, Sabatier JM, Fajloun Z. Inhibitors of ATP Synthase as New Antibacterial Candidates. Antibiotics (Basel) 2023; 12:antibiotics12040650. [PMID: 37107012 PMCID: PMC10135114 DOI: 10.3390/antibiotics12040650] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2023] [Revised: 03/20/2023] [Accepted: 03/22/2023] [Indexed: 03/29/2023] Open
Abstract
ATP, the power of all cellular functions, is constantly used and produced by cells. The enzyme called ATP synthase is the energy factory in all cells, which produces ATP by adding inorganic phosphate (Pi) to ADP. It is found in the inner, thylakoid and plasma membranes of mitochondria, chloroplasts and bacteria, respectively. Bacterial ATP synthases have been the subject of multiple studies for decades, since they can be genetically manipulated. With the emergence of antibiotic resistance, many combinations of antibiotics with other compounds that enhance the effect of these antibiotics have been proposed as approaches to limit the spread of antibiotic-resistant bacteria. ATP synthase inhibitors, such as resveratrol, venturicidin A, bedaquiline, tomatidine, piceatannol, oligomycin A and N,N-dicyclohexylcarbodiimide were the starting point of these combinations. However, each of these inhibitors target ATP synthase differently, and their co-administration with antibiotics increases the susceptibility of pathogenic bacteria. After a brief description of the structure and function of ATP synthase, we aim in this review to highlight therapeutic applications of the major bacterial ATP synthase inhibitors, including animal’s venoms, and to emphasize their importance in decreasing the activity of this enzyme and subsequently eradicating resistant bacteria as ATP synthase is their source of energy.
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6
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F1·Fo ATP Synthase/ATPase: Contemporary View on Unidirectional Catalysis. Int J Mol Sci 2023; 24:ijms24065417. [PMID: 36982498 PMCID: PMC10049701 DOI: 10.3390/ijms24065417] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2023] [Revised: 03/05/2023] [Accepted: 03/10/2023] [Indexed: 03/14/2023] Open
Abstract
F1·Fo-ATP synthases/ATPases (F1·Fo) are molecular machines that couple either ATP synthesis from ADP and phosphate or ATP hydrolysis to the consumption or production of a transmembrane electrochemical gradient of protons. Currently, in view of the spread of drug-resistant disease-causing strains, there is an increasing interest in F1·Fo as new targets for antimicrobial drugs, in particular, anti-tuberculosis drugs, and inhibitors of these membrane proteins are being considered in this capacity. However, the specific drug search is hampered by the complex mechanism of regulation of F1·Fo in bacteria, in particular, in mycobacteria: the enzyme efficiently synthesizes ATP, but is not capable of ATP hydrolysis. In this review, we consider the current state of the problem of “unidirectional” F1·Fo catalysis found in a wide range of bacterial F1·Fo and enzymes from other organisms, the understanding of which will be useful for developing a strategy for the search for new drugs that selectively disrupt the energy production of bacterial cells.
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7
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Structural Elements Involved in ATP Hydrolysis Inhibition and ATP Synthesis of Tuberculosis and Nontuberculous Mycobacterial F-ATP Synthase Decipher New Targets for Inhibitors. Antimicrob Agents Chemother 2022; 66:e0105622. [PMID: 36445139 PMCID: PMC9764993 DOI: 10.1128/aac.01056-22] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/03/2022] Open
Abstract
The F1FO-ATP synthase is required for the viability of tuberculosis (TB) and nontuberculous mycobacteria (NTM) and has been validated as a drug target. Here, we present the cryo-EM structures of the Mycobacterium smegmatis F1-ATPase and the F1FO-ATP synthase with different nucleotide occupation within the catalytic sites and visualize critical elements for latent ATP hydrolysis and efficient ATP synthesis. Mutational studies reveal that the extended C-terminal domain (αCTD) of subunit α is the main element for the self-inhibition mechanism of ATP hydrolysis for TB and NTM bacteria. Rotational studies indicate that the transition between the inhibition state by the αCTD and the active state is a rapid process. We demonstrate that the unique mycobacterial γ-loop and subunit δ are critical elements required for ATP formation. The data underline that these mycobacterium-specific elements of α, γ, and δ are attractive targets, providing a platform for the discovery of species-specific inhibitors.
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8
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Anti-Mycobacterium abscessus Activity of Tuberculosis F-ATP Synthase Inhibitor GaMF1. Antimicrob Agents Chemother 2022; 66:e0001822. [PMID: 35481752 PMCID: PMC9112937 DOI: 10.1128/aac.00018-22] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
New drug targets and molecules with bactericidal activity are needed against the respiratory mycobacterial pathogen Mycobacterium abscessus. Employing a lead repurposing strategy, the antituberculosis compound GaMF1 was tested against M. abscessus. Whole-cell and ATP synthesis assays demonstrated that GaMF1 inhibits growth and kills M. abscessus by targeting the F-ATP synthase. GaMF1's anti-M. abscessus activity increased in combination with clofazimine, rifabutin, or amikacin. The study expands the repertoire of anti-M. abscessus compounds targeting oxidative phosphorylation.
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9
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Harikishore A, Saw WG, Ragunathan P, Litty D, Dick T, Müller V, Grüber G. Mutational Analysis of Mycobacterial F-ATP Synthase Subunit δ Leads to a Potent δ Enzyme Inhibitor. ACS Chem Biol 2022; 17:529-535. [PMID: 35148057 DOI: 10.1021/acschembio.1c00766] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
While many bacteria are able to bypass the requirement for oxidative phosphorylation when grown on carbohydrates, Mycobacterium tuberculosis is unable to do so. Differences of amino acid composition and structural features of the mycobacterial F-ATP synthase (α3:β3:γ:δ:ε:a:b:b':c9) compared to its prokaryotic or human counterparts were recently elucidated and paved avenues for the discovery of molecules interfering with various regulative mechanisms of this essential energy converter. In this context, the mycobacterial peripheral stalk subunit δ came into focus, which displays a unique N-terminal 111-amino acid extension. Here, mutants of recombinant mycobacterial subunit δ were characterized, revealing significant reduction in ATP synthesis and demonstrating essentiality of this subunit for effective catalysis. These results provided the basis for the generation of a four-feature model forming a δ receptor-based pharmacophore and to identify a potent subunit δ inhibitor DeMF1 via in silico screening. The successful targeting of the δ subunit demonstrates the potential to advance δ's flexible coupling as a new area for the development of F-ATP synthase inhibitors.
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Affiliation(s)
- Amaravadhi Harikishore
- School of Biological Sciences, Nanyang Technological University, 60 Nanyang Drive, Singapore 637551, Republic of Singapore
| | - Wuan-Geok Saw
- School of Biological Sciences, Nanyang Technological University, 60 Nanyang Drive, Singapore 637551, Republic of Singapore
| | - Priya Ragunathan
- School of Biological Sciences, Nanyang Technological University, 60 Nanyang Drive, Singapore 637551, Republic of Singapore
| | - Dennis Litty
- Molecular Microbiology and Bioenergetics, Institute of Molecular Biosciences Johann Wolfgang Goethe University Frankfurt/Main, Max-von-Laue-Str. 9, 60438 Frankfurt, Germany
| | - Thomas Dick
- Center for Discovery and Innovation, Hackensack Meridian Health, 111 Ideation Way, Nutley, New Jersey 07110, United States
- Medical Sciences, Hackensack Meridian School of Medicine, 123 Metro Boulevard, Nutley, New Jersey 07110, United States
- Department of Microbiology and Immunology, Georgetown University, 3900 Reservoir Road NW Medical-Dental Building, Washington, D.C. 20007, United States
| | - Volker Müller
- Molecular Microbiology and Bioenergetics, Institute of Molecular Biosciences Johann Wolfgang Goethe University Frankfurt/Main, Max-von-Laue-Str. 9, 60438 Frankfurt, Germany
| | - Gerhard Grüber
- School of Biological Sciences, Nanyang Technological University, 60 Nanyang Drive, Singapore 637551, Republic of Singapore
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10
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Targeting Mycobacterial F-ATP Synthase C-Terminal α Subunit Interaction Motif on Rotary Subunit γ. Antibiotics (Basel) 2021; 10:antibiotics10121456. [PMID: 34943667 PMCID: PMC8698299 DOI: 10.3390/antibiotics10121456] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2021] [Revised: 11/22/2021] [Accepted: 11/24/2021] [Indexed: 12/03/2022] Open
Abstract
Mycobacteria regulate their energy (ATP) levels to sustain their survival even in stringent living conditions. Recent studies have shown that mycobacteria not only slow down their respiratory rate but also block ATP hydrolysis of the F-ATP synthase (α3:β3:γ:δ:ε:a:b:b’:c9) to maintain ATP homeostasis in situations not amenable for growth. The mycobacteria-specific α C-terminus (α533-545) has unraveled to be the major regulative of latent ATP hydrolysis. Its deletion stimulates ATPase activity while reducing ATP synthesis. In one of the six rotational states of F-ATP synthase, α533-545 has been visualized to dock deep into subunit γ, thereby blocking rotation of γ within the engine. The functional role(s) of this C-terminus in the other rotational states are not clarified yet and are being still pursued in structural studies. Based on the interaction pattern of the docked α533-545 region with subunit γ, we attempted to study the druggability of the α533-545 motif. In this direction, our computational work has led to the development of an eight-featured α533-545 peptide pharmacophore, followed by database screening, molecular docking, and pose selection, resulting in eleven hit molecules. ATP synthesis inhibition assays using recombinant ATP synthase as well as mycobacterial inverted membrane vesicles show that one of the hits, AlMF1, inhibited the mycobacterial F-ATP synthase in a micromolar range. The successful targeting of the α533-545-γ interaction motif demonstrates the potential to develop inhibitors targeting the α site to interrupt rotary coupling with ATP synthesis.
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11
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Montgomery MG, Petri J, Spikes TE, Walker JE. Structure of the ATP synthase from Mycobacterium smegmatis provides targets for treating tuberculosis. Proc Natl Acad Sci U S A 2021; 118:e2111899118. [PMID: 34782468 PMCID: PMC8617483 DOI: 10.1073/pnas.2111899118] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2021] [Accepted: 10/13/2021] [Indexed: 01/01/2023] Open
Abstract
The structure has been determined by electron cryomicroscopy of the adenosine triphosphate (ATP) synthase from Mycobacterium smegmatis This analysis confirms features in a prior description of the structure of the enzyme, but it also describes other highly significant attributes not recognized before that are crucial for understanding the mechanism and regulation of the mycobacterial enzyme. First, we resolved not only the three main states in the catalytic cycle described before but also eight substates that portray structural and mechanistic changes occurring during a 360° catalytic cycle. Second, a mechanism of auto-inhibition of ATP hydrolysis involves not only the engagement of the C-terminal region of an α-subunit in a loop in the γ-subunit, as proposed before, but also a "fail-safe" mechanism involving the b'-subunit in the peripheral stalk that enhances engagement. A third unreported characteristic is that the fused bδ-subunit contains a duplicated domain in its N-terminal region where the two copies of the domain participate in similar modes of attachment of the two of three N-terminal regions of the α-subunits. The auto-inhibitory plus the associated "fail-safe" mechanisms and the modes of attachment of the α-subunits provide targets for development of innovative antitubercular drugs. The structure also provides support for an observation made in the bovine ATP synthase that the transmembrane proton-motive force that provides the energy to drive the rotary mechanism is delivered directly and tangentially to the rotor via a Grotthuss water chain in a polar L-shaped tunnel.
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Affiliation(s)
- Martin G Montgomery
- The Medical Research Council Mitochondrial Biology Unit, University of Cambridge, Cambridge CB2 0XY, United Kingdom
| | - Jessica Petri
- The Medical Research Council Mitochondrial Biology Unit, University of Cambridge, Cambridge CB2 0XY, United Kingdom
| | - Tobias E Spikes
- The Medical Research Council Mitochondrial Biology Unit, University of Cambridge, Cambridge CB2 0XY, United Kingdom
| | - John E Walker
- The Medical Research Council Mitochondrial Biology Unit, University of Cambridge, Cambridge CB2 0XY, United Kingdom
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12
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Ragunathan P, Cole M, Latka C, Aragaw WW, Hegde P, Shin J, Subramanian Manimekalai MS, Rishikesan S, Aldrich CC, Dick T, Grüber G. Mycobacterium tuberculosis PanD Structure-Function Analysis and Identification of a Potent Pyrazinoic Acid-Derived Enzyme Inhibitor. ACS Chem Biol 2021; 16:1030-1039. [PMID: 33984234 DOI: 10.1021/acschembio.1c00131] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
A common strategy employed in antibacterial drug discovery is the targeting of biosynthetic processes that are essential and specific for the pathogen. Specificity in particular avoids undesirable interactions with potential enzymatic counterparts in the human host, and it ensures on-target toxicity. Synthesis of pantothenate (Vitamine B5), which is a precursor of the acyl carrier coenzyme A, is an example of such a pathway. In Mycobacterium tuberculosis (Mtb), which is the causative agent of tuberculosis (TB), pantothenate is formed by pantothenate synthase, utilizing D-pantoate and β-Ala as substrates. β-Ala is mainly formed by the decarboxylation of l-aspartate, generated by the decarboxylase PanD, which is a homo-oliogomer in solution. Pyrazinoic acid (POA), which is the bioactive form of the TB prodrug pyrazinamide, binds and inhibits PanD activity weakly. Here, we generated a library of recombinant Mtb PanD mutants based on structural information and PZA/POA resistance mutants. Alterations in oligomer formation, enzyme activity, and/or POA binding were observed in respective mutants, providing insights into essential amino acids for Mtb PanD's proper structural assembly, decarboxylation activity and drug interaction. This information provided the platform for the design of novel POA analogues with modifications at position 3 of the pyrazine ring. Analogue 2, which incorporates a bulky naphthamido group at this position, displayed a 1000-fold increase in enzyme inhibition, compared to POA, along with moderately improved antimycobacterial activity. The data demonstrate that an improved understanding of mechanistic and enzymatic features of key metabolic enzymes can stimulate design of more-potent PanD inhibitors.
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Affiliation(s)
- Priya Ragunathan
- School of Biological Sciences, Nanyang Technological University, 60 Nanyang Drive, Singapore 637551, Republic of Singapore
| | - Malcolm Cole
- University of Minnesota, College of Pharmacy, Department of Medicinal Chemistry 8-101 Weaver-Densford Hall 308 Harvard St. SE, Minneapolis, Minnesota 55455, United States
| | - Chitra Latka
- School of Biological Sciences, Nanyang Technological University, 60 Nanyang Drive, Singapore 637551, Republic of Singapore
| | - Wassihun Wedajo Aragaw
- Center for Discovery and Innovation, Hackensack Meridian Health, 111 Ideation Way, Nutley, New Jersey 07110, United States
| | - Pooja Hegde
- University of Minnesota, College of Pharmacy, Department of Medicinal Chemistry 8-101 Weaver-Densford Hall 308 Harvard St. SE, Minneapolis, Minnesota 55455, United States
| | - Joon Shin
- School of Biological Sciences, Nanyang Technological University, 60 Nanyang Drive, Singapore 637551, Republic of Singapore
| | | | - Sankaranarayanan Rishikesan
- School of Biological Sciences, Nanyang Technological University, 60 Nanyang Drive, Singapore 637551, Republic of Singapore
| | - Courtney C. Aldrich
- University of Minnesota, College of Pharmacy, Department of Medicinal Chemistry 8-101 Weaver-Densford Hall 308 Harvard St. SE, Minneapolis, Minnesota 55455, United States
| | - Thomas Dick
- Center for Discovery and Innovation, Hackensack Meridian Health, 111 Ideation Way, Nutley, New Jersey 07110, United States
- Department of Medical Sciences, Hackensack Meridian School of Medicine, 123 Metro Boulevard, Nutley, New Jersey 07110, United States
- Department of Microbiology and Immunology, Georgetown University, 3900 Reservoir Road NW Medical-Dental Building, Washington, District of Columbia 20007, United States
| | - Gerhard Grüber
- School of Biological Sciences, Nanyang Technological University, 60 Nanyang Drive, Singapore 637551, Republic of Singapore
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13
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Di Fermo P, Di Lodovico S, Amoroso R, De Filippis B, D’Ercole S, Di Campli E, Cellini L, Di Giulio M. Searching for New Tools to Counteract the Helicobacter pylori Resistance: The Positive Action of Resveratrol Derivatives. Antibiotics (Basel) 2020; 9:E891. [PMID: 33322025 PMCID: PMC7763357 DOI: 10.3390/antibiotics9120891] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2020] [Revised: 12/04/2020] [Accepted: 12/08/2020] [Indexed: 01/02/2023] Open
Abstract
The drug-resistance phenomenon in Helicobacter pylori underlines the need of novel strategies to improve the eradication rate including alternative treatments combining antibiotic and non-antibiotic compounds with synergistic action. In this study, the antibacterial (MIC/MBC) and anti-virulence effects (biofilm reduction and swarming motility inhibition) of resveratrol-RSV and new synthetized RSV-phenol derivatives, with a higher bioavailability, alone and combined with levofloxacin-LVX were evaluated against resistant H. pylori clinical strains. The experiments were confirmed in vivo using the Galleria mellonella model. Among the studied RSV derivatives, RSV-3 and RSV-4 possessed higher antibacterial activity with respect to RSV (MICs from 6.25 to 200 µg/mL and from 3.12 to 200 µg/mL, respectively). RSV, RSV-3, and RSV-4 were able to synergize with LVX restoring its effect in two out of seven clinical resistant strains tested for the study. RSV, RSV-3, and RSV-4, alone and with LVX at sub-MIC and sub-synergistic concentrations, significantly reduced the biofilm formation. Moreover, RSV-3 and RSV-4 reduced the H. pylori swarming motility on soft agar. RSV, RSV-3, and RSV-4 were non-toxic for G. mellonella larvae and displayed a protective effect against H. pylori infection. Overall, RSV-phenol derivatives should be considered interesting candidates for innovative therapeutic schemes to tackle the H. pylori antibiotic resistance.
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Affiliation(s)
- Paola Di Fermo
- Department of Pharmacy, University “G. d’Annunzio” Chieti-Pescara, Via dei Vestini 31, 66100 Chieti, Italy; (P.D.F.); (S.D.L.); (R.A.); (B.D.F.); (E.D.C.); (M.D.G.)
| | - Silvia Di Lodovico
- Department of Pharmacy, University “G. d’Annunzio” Chieti-Pescara, Via dei Vestini 31, 66100 Chieti, Italy; (P.D.F.); (S.D.L.); (R.A.); (B.D.F.); (E.D.C.); (M.D.G.)
| | - Rosa Amoroso
- Department of Pharmacy, University “G. d’Annunzio” Chieti-Pescara, Via dei Vestini 31, 66100 Chieti, Italy; (P.D.F.); (S.D.L.); (R.A.); (B.D.F.); (E.D.C.); (M.D.G.)
| | - Barbara De Filippis
- Department of Pharmacy, University “G. d’Annunzio” Chieti-Pescara, Via dei Vestini 31, 66100 Chieti, Italy; (P.D.F.); (S.D.L.); (R.A.); (B.D.F.); (E.D.C.); (M.D.G.)
| | - Simonetta D’Ercole
- Department of Medical Oral and Biotechnological Sciences, University “G. d’Annunzio” Chieti-Pescara, Via dei Vestini 31, 66100 Chieti, Italy;
| | - Emanuela Di Campli
- Department of Pharmacy, University “G. d’Annunzio” Chieti-Pescara, Via dei Vestini 31, 66100 Chieti, Italy; (P.D.F.); (S.D.L.); (R.A.); (B.D.F.); (E.D.C.); (M.D.G.)
| | - Luigina Cellini
- Department of Pharmacy, University “G. d’Annunzio” Chieti-Pescara, Via dei Vestini 31, 66100 Chieti, Italy; (P.D.F.); (S.D.L.); (R.A.); (B.D.F.); (E.D.C.); (M.D.G.)
| | - Mara Di Giulio
- Department of Pharmacy, University “G. d’Annunzio” Chieti-Pescara, Via dei Vestini 31, 66100 Chieti, Italy; (P.D.F.); (S.D.L.); (R.A.); (B.D.F.); (E.D.C.); (M.D.G.)
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14
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The Unique C-Terminal Extension of Mycobacterial F-ATP Synthase Subunit α Is the Major Contributor to Its Latent ATP Hydrolysis Activity. Antimicrob Agents Chemother 2020; 64:AAC.01568-20. [PMID: 32988828 DOI: 10.1128/aac.01568-20] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2020] [Accepted: 09/16/2020] [Indexed: 01/03/2023] Open
Abstract
Mycobacterial F1Fo-ATP synthases (α3:β3:γ:δ:ε:a:b:b':c9 ) are incapable of ATP-driven proton translocation due to their latent ATPase activity. This prevents wasting of ATP and altering of the proton motive force, whose dissipation is lethal to mycobacteria. We demonstrate that the mycobacterial C-terminal extension of nucleotide-binding subunit α contributes mainly to the suppression of ATPase activity in the recombinant mycobacterial F1-ATPase. Using C-terminal deletion mutants, the regions responsible for the enzyme's latency were mapped, providing a new compound epitope.
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15
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Sartor P, Bock J, Hennecke U, Thierbach S, Fetzner S. Modification of the Pseudomonas aeruginosa toxin 2-heptyl-1-hydroxyquinolin-4(1H)-one and other secondary metabolites by methyltransferases from mycobacteria. FEBS J 2020; 288:2360-2376. [PMID: 33064871 DOI: 10.1111/febs.15595] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2020] [Revised: 09/22/2020] [Accepted: 10/12/2020] [Indexed: 11/26/2022]
Abstract
The opportunistic pathogen Pseudomonas aeruginosa, one of the most prevalent species in infections of the cystic fibrosis lung, produces a range of secondary metabolites, among them the respiratory toxin 2-heptyl-1-hydroxyquinolin-4(1H)-one (2-heptyl-4-hydroxyquinoline N-oxide, HQNO). Cultures of the emerging cystic fibrosis pathogen Mycobacteroides abscessus detoxify HQNO by methylating the N-hydroxy moiety. In this study, the class I methyltransferase MAB_2834c and its orthologue from Mycobacterium tuberculosis, Rv0560c, were identified as HQNO O-methyltransferases. The P. aeruginosa exoproducts 4-hydroxyquinolin-2(1H)-one (DHQ), 2-heptylquinolin-4(1H)-one (HHQ), and 2-heptyl-3-hydroxyquinolin-4(1H)-one (the 'Pseudomonas quinolone signal', PQS), some structurally related (iso)quinolones, and the flavonol quercetin were also methylated; however, HQNO was by far the preferred substrate. Both enzymes converted a benzimidazole[1,2-a]pyridine-4-carbonitrile-based compound, representing the scaffold of antimycobacterial substances, to an N-methylated derivative. We suggest that these promiscuous methyltransferases, newly termed as heterocyclic toxin methyltransferases (Htm), are involved in cellular response to chemical stress and possibly contribute to resistance of mycobacteria toward antimicrobial natural compounds as well as drugs. Thus, synthetic antimycobacterial agents may be designed to be unamenable to methyl transfer. ENZYMES: S-adenosyl-l-methionine:2-heptyl-1-hydroxyquinolin-4(1H)-one O-methyl-transferase, EC 2.1.1.
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Affiliation(s)
- Pascal Sartor
- Institute for Molecular Microbiology and Biotechnology, University of Münster, Germany
| | - Jonathan Bock
- Organic Chemistry Research Group, Department of Chemistry and Department of Bioengineering Sciences, Vrije Universiteit Brussels, Belgium
| | - Ulrich Hennecke
- Organic Chemistry Research Group, Department of Chemistry and Department of Bioengineering Sciences, Vrije Universiteit Brussels, Belgium
| | - Sven Thierbach
- Institute for Molecular Microbiology and Biotechnology, University of Münster, Germany
| | - Susanne Fetzner
- Institute for Molecular Microbiology and Biotechnology, University of Münster, Germany
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16
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Appetecchia F, Consalvi S, Scarpecci C, Biava M, Poce G. SAR Analysis of Small Molecules Interfering with Energy-Metabolism in Mycobacterium tuberculosis. Pharmaceuticals (Basel) 2020; 13:E227. [PMID: 32878317 PMCID: PMC7557483 DOI: 10.3390/ph13090227] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2020] [Revised: 08/28/2020] [Accepted: 08/28/2020] [Indexed: 12/13/2022] Open
Abstract
Tuberculosis remains the world's top infectious killer: it caused a total of 1.5 million deaths and 10 million people fell ill with TB in 2018. Thanks to TB diagnosis and treatment, mortality has been falling in recent years, with an estimated 58 million saved lives between 2000 and 2018. However, the emergence of multidrug-resistant (MDR) and extensively drug-resistant (XDR) Mtb strains is a major concern that might reverse this progress. Therefore, the development of new drugs acting upon novel mechanisms of action is a high priority in the global health agenda. With the approval of bedaquiline, which targets mycobacterial energy production, and delamanid, which targets cell wall synthesis and energy production, the energy-metabolism in Mtb has received much attention in the last decade as a potential target to investigate and develop new antimycobacterial drugs. In this review, we describe potent anti-mycobacterial agents targeting the energy-metabolism at different steps with a special focus on structure-activity relationship (SAR) studies of the most advanced compound classes.
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Affiliation(s)
| | | | | | | | - Giovanna Poce
- Department of Chemistry and Technologies of Drug, Sapienza University of Rome, piazzale A. Moro 5, 00185 Rome, Italy; (F.A.); (S.C.); (C.S.); (M.B.)
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17
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Sviriaeva E, Subramanian Manimekalai MS, Grüber G, Pethe K. Features and Functional Importance of Key Residues of the Mycobacterium tuberculosis Cytochrome bd Oxidase. ACS Infect Dis 2020; 6:1697-1707. [PMID: 32379966 DOI: 10.1021/acsinfecdis.9b00449] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Cytochrome bd (cyt-bd) oxygen reductases have a high affinity to oxygen and use the two electrons provided by ubiquinol or menaquinol, like in mycobacteria, to reduce oxygen to water. Although they do not pump protons from the cytoplasmic to the periplasmic side, they generate a proton motive force due to the release of protons after quinol oxidation. Here, we show that the mycobacterial cyt-bd has a number of specific features, including a 17-residue stretch (307SGVTLQGIRDLQQEYQQ323) near the Q-loop of the Mycobacterium tuberculosis subunit CydA and a 412QLVRLTVKA420 region on the periplasmic side. Site directed mutagenesis and whole-bacteria assays demonstrated that these mycobacteria-specific stretches are essential for the oxidase's function. Single amino acid substitutions around the 307SGVTLQGIRDLQQEYQQ323 stretch revealed the importance of the aromatic residue Y330 in oxygen consumption and consequently in ATP synthesis. A moderate reduction and no effect was observed for mutants F325 and Y321, respectively, while the double mutant CydAY321/F325 drastically reduced enzyme activity. In addition, single mutants of the mycobacterial cyt-bd were generated to probe the role of proposed critical residues for proton shuffling. Further data demonstrate that amino acids W64 and F18 in the CydB subunit might be important as any slight destabilization of the hydrophobic environment near them makes the enzyme inactive. Finally, the potential of the mycobacterial cyt-bd as a drug target is discussed.
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Affiliation(s)
- Ekaterina Sviriaeva
- Nanyang Technological University, School of Biological Sciences, 60 Nanyang Drive, Singapore 637551, Republic of Singapore
- Lee Kong Chian School of Medicine, 59 Nanyang Drive, Singapore 636921, Republic of Singapore
| | | | - Gerhard Grüber
- Nanyang Technological University, School of Biological Sciences, 60 Nanyang Drive, Singapore 637551, Republic of Singapore
| | - Kevin Pethe
- Nanyang Technological University, School of Biological Sciences, 60 Nanyang Drive, Singapore 637551, Republic of Singapore
- Lee Kong Chian School of Medicine, 59 Nanyang Drive, Singapore 636921, Republic of Singapore
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18
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Wong CF, Lau AM, Harikishore A, Saw WG, Shin J, Ragunathan P, Bhushan S, Ngan SFC, Sze SK, Bates RW, Dick T, Grüber G. A systematic assessment of mycobacterial F 1 -ATPase subunit ε's role in latent ATPase hydrolysis. FEBS J 2020; 288:818-836. [PMID: 32525613 DOI: 10.1111/febs.15440] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2019] [Revised: 05/05/2020] [Accepted: 06/03/2020] [Indexed: 12/20/2022]
Abstract
In contrast to most bacteria, the mycobacterial F1 FO -ATP synthase (α3 :β3 :γ:δ:ε:a:b:b':c9 ) does not perform ATP hydrolysis-driven proton translocation. Although subunits α, γ and ε of the catalytic F1 -ATPase component α3 :β3 :γ:ε have all been implicated in the suppression of the enzyme's ATPase activity, the mechanism remains poorly defined. Here, we brought the central stalk subunit ε into focus by generating the recombinant Mycobacterium smegmatis F1 -ATPase (MsF1 -ATPase), whose 3D low-resolution structure is presented, and its ε-free form MsF1 αβγ, which showed an eightfold ATP hydrolysis increase and provided a defined system to systematically study the segments of mycobacterial ε's suppression of ATPase activity. Deletion of four amino acids at ε's N terminus, mutant MsF1 αβγεΔ2-5 , revealed similar ATP hydrolysis as MsF1 αβγ. Together with biochemical and NMR solution studies of a single, double, triple and quadruple N-terminal ε-mutants, the importance of the first N-terminal residues of mycobacterial ε in structure stability and latency is described. Engineering ε's C-terminal mutant MsF1 αβγεΔ121 and MsF1 αβγεΔ103-121 with deletion of the C-terminal residue D121 and the two C-terminal ɑ-helices, respectively, revealed the requirement of the very C terminus for communication with the catalytic α3 β3 -headpiece and its function in ATP hydrolysis inhibition. Finally, we applied the tools developed during the study for an in silico screen to identify a novel subunit ε-targeting F-ATP synthase inhibitor.
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Affiliation(s)
- Chui-Fann Wong
- School of Biological Sciences, Nanyang Technological University, Singapore City, Singapore
| | - Aik-Meng Lau
- School of Biological Sciences, Nanyang Technological University, Singapore City, Singapore
| | - Amaravadhi Harikishore
- Division of Chemistry and Biological Chemistry, School of Physical and Mathematical Sciences, Nanyang Technological University, Singapore City, Singapore
| | - Wuan-Geok Saw
- School of Biological Sciences, Nanyang Technological University, Singapore City, Singapore
| | - Joon Shin
- School of Biological Sciences, Nanyang Technological University, Singapore City, Singapore
| | - Priya Ragunathan
- School of Biological Sciences, Nanyang Technological University, Singapore City, Singapore
| | - Shashi Bhushan
- School of Biological Sciences, Nanyang Technological University, Singapore City, Singapore.,NTU Institute of Structural Biology, Nanyang Technological University, Singapore City, Singapore
| | - So-Fong Cam Ngan
- School of Biological Sciences, Nanyang Technological University, Singapore City, Singapore
| | - Siu Kwan Sze
- School of Biological Sciences, Nanyang Technological University, Singapore City, Singapore
| | - Roderick W Bates
- Division of Chemistry and Biological Chemistry, School of Physical and Mathematical Sciences, Nanyang Technological University, Singapore City, Singapore
| | - Thomas Dick
- Center for Discovery and Innovation, Hackensack Meridian Health, Nutley, NJ, USA.,Department of Microbiology and Immunology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore City, Singapore.,Department of Medical Sciences, Hackensack Meridian School of Medicine at Seton Hall University, Nutley, NJ, USA
| | - Gerhard Grüber
- School of Biological Sciences, Nanyang Technological University, Singapore City, Singapore
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19
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Kamariah N, Huber RG, Bond PJ, Müller V, Grüber G. 3D reconstruction and flexibility of the hybrid engine Acetobacterium woodii F-ATP synthase. Biochem Biophys Res Commun 2020; 527:518-524. [PMID: 32423799 DOI: 10.1016/j.bbrc.2020.04.026] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2020] [Accepted: 04/09/2020] [Indexed: 11/16/2022]
Abstract
The Na+-translocating F1FO ATP synthase from Acetobacterium woodii (AwF-ATP synthase) with a subunit stoichiometry of α3:β3:γ:δ:ε:a:b2:(c2/3)9:c1 represents an evolutionary path between ATP-synthases and vacuolar ATPases, by containing a heteromeric rotor c-ring, composed of subunits c1, c2 and c3, and an extra loop (γ195-211) within the rotary γ subunit. Here, the recombinant AwF-ATP synthase was subjected to negative stain electron microscopy and single particle analysis. The reference free 2D class averages revealed high flexibility of the enzyme, wherein the F1 and FO domains distinctively bended to adopt multiple conformations. Moreover, both the F1 and FO domains tilted relative to each other to a maximum extent of 28° and 30°, respectively. The first 3D reconstruction of the AwF-ATP synthase was determined which accommodates well the modelled structure of the AwF-ATP synthase as well as the γ195-211-loop. Molecular simulations of the enzyme underlined the bending features and flexibility observed in the electron micrographs, and enabled assessment of the dynamics of the extra γ195-211-loop.
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Affiliation(s)
- Neelagandan Kamariah
- Nanyang Technological University, School of Biological Sciences, 60 Nanyang Drive, Singapore, 637551, Republic of Singapore
| | - Roland G Huber
- Bioinformatics Institute (BII), Agency for Science, Technology and Research (A∗STAR), #07-01 Matrix, 30 Biopolis Street, Singapore, 38671
| | - Peter J Bond
- Bioinformatics Institute (BII), Agency for Science, Technology and Research (A∗STAR), #07-01 Matrix, 30 Biopolis Street, Singapore, 38671; Department of Biological Sciences (DBS), National University of Singapore (NUS), 14 Science Drive 4, Singapore, 117543
| | - Volker Müller
- Molecular Microbiology & Bioenergetics, Institute of Molecular Biosciences, Johann Wolfgang Goethe University Frankfurt/Main, Max-von-Laue-Str. 9, 60438, Frankfurt, Germany
| | - Gerhard Grüber
- Nanyang Technological University, School of Biological Sciences, 60 Nanyang Drive, Singapore, 637551, Republic of Singapore; Bioinformatics Institute (BII), Agency for Science, Technology and Research (A∗STAR), #07-01 Matrix, 30 Biopolis Street, Singapore, 38671.
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20
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Hotra A, Ragunathan P, Ng PS, Seankongsuk P, Harikishore A, Sarathy JP, Saw W, Lakshmanan U, Sae‐Lao P, Kalia NP, Shin J, Kalyanasundaram R, Anbarasu S, Parthasarathy K, Pradeep CN, Makhija H, Dröge P, Poulsen A, Tan JHL, Pethe K, Dick T, Bates RW, Grüber G. Discovery of a Novel Mycobacterial F‐ATP Synthase Inhibitor and its Potency in Combination with Diarylquinolines. Angew Chem Int Ed Engl 2020; 59:13295-13304. [DOI: 10.1002/anie.202002546] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2020] [Indexed: 01/08/2023]
Affiliation(s)
- Adam Hotra
- School of Physical and Mathematical Sciences Nanyang Technological University 21 Nanyang Link Singapore 637371 Republic of Singapore
- School of Biological Sciences Nanyang Technological University 60 Nanyang Drive Singapore 637551 Republic of Singapore
- Nanyang Institute of Technology in Health and Medicine Interdisciplinary Graduate School Nanyang Technological University Republic of Singapore
| | - Priya Ragunathan
- School of Biological Sciences Nanyang Technological University 60 Nanyang Drive Singapore 637551 Republic of Singapore
| | - Pearly Shuyi Ng
- Experimental Drug Development Centre Agency for Science Technology and Research, A*STAR 10 Biopolis Road Singapore 138670 Republic of Singapore
| | - Pattarakiat Seankongsuk
- School of Physical and Mathematical Sciences Nanyang Technological University 21 Nanyang Link Singapore 637371 Republic of Singapore
| | - Amaravadhi Harikishore
- School of Physical and Mathematical Sciences Nanyang Technological University 21 Nanyang Link Singapore 637371 Republic of Singapore
- School of Biological Sciences Nanyang Technological University 60 Nanyang Drive Singapore 637551 Republic of Singapore
| | - Jickky Palmae Sarathy
- Department of Microbiology and Immunology Yong Loo Lin School of Medicine National University of Singapore 14 Medical Drive Singapore 117599 Republic of Singapore
| | - Wuan‐Geok Saw
- School of Biological Sciences Nanyang Technological University 60 Nanyang Drive Singapore 637551 Republic of Singapore
| | - Umayal Lakshmanan
- Experimental Drug Development Centre Agency for Science Technology and Research, A*STAR 10 Biopolis Road Singapore 138670 Republic of Singapore
| | - Patcharaporn Sae‐Lao
- School of Physical and Mathematical Sciences Nanyang Technological University 21 Nanyang Link Singapore 637371 Republic of Singapore
| | - Nitin Pal Kalia
- Lee Kong Chian School of Medicine Nanyang Technological University Experimental Medicine Building Republic of Singapore
| | - Joon Shin
- School of Biological Sciences Nanyang Technological University 60 Nanyang Drive Singapore 637551 Republic of Singapore
| | - Revathy Kalyanasundaram
- Centre for Drug Discovery and Development Sathyabama Institute of Science and Technology Chennai 600119 India
| | - Sivaraj Anbarasu
- Centre for Drug Discovery and Development Sathyabama Institute of Science and Technology Chennai 600119 India
| | - Krupakar Parthasarathy
- Centre for Drug Discovery and Development Sathyabama Institute of Science and Technology Chennai 600119 India
| | - Chaudhari Namrata Pradeep
- School of Biological Sciences Nanyang Technological University 60 Nanyang Drive Singapore 637551 Republic of Singapore
| | - Harshyaa Makhija
- School of Biological Sciences Nanyang Technological University 60 Nanyang Drive Singapore 637551 Republic of Singapore
| | - Peter Dröge
- School of Biological Sciences Nanyang Technological University 60 Nanyang Drive Singapore 637551 Republic of Singapore
| | - Anders Poulsen
- Experimental Drug Development Centre Agency for Science Technology and Research, A*STAR 10 Biopolis Road Singapore 138670 Republic of Singapore
| | - Jocelyn Hui Ling Tan
- Experimental Drug Development Centre Agency for Science Technology and Research, A*STAR 10 Biopolis Road Singapore 138670 Republic of Singapore
| | - Kevin Pethe
- School of Biological Sciences Nanyang Technological University 60 Nanyang Drive Singapore 637551 Republic of Singapore
- Lee Kong Chian School of Medicine Nanyang Technological University Experimental Medicine Building Republic of Singapore
| | - Thomas Dick
- Department of Microbiology and Immunology Yong Loo Lin School of Medicine National University of Singapore 14 Medical Drive Singapore 117599 Republic of Singapore
- Center for Discovery and Innovation Hackensack Meridian Health 340 Kingsland Street Nutley NJ 07110 USA
| | - Roderick W. Bates
- School of Physical and Mathematical Sciences Nanyang Technological University 21 Nanyang Link Singapore 637371 Republic of Singapore
| | - Gerhard Grüber
- School of Biological Sciences Nanyang Technological University 60 Nanyang Drive Singapore 637551 Republic of Singapore
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21
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Hotra A, Ragunathan P, Ng PS, Seankongsuk P, Harikishore A, Sarathy JP, Saw W, Lakshmanan U, Sae‐Lao P, Kalia NP, Shin J, Kalyanasundaram R, Anbarasu S, Parthasarathy K, Pradeep CN, Makhija H, Dröge P, Poulsen A, Tan JHL, Pethe K, Dick T, Bates RW, Grüber G. Discovery of a Novel Mycobacterial F‐ATP Synthase Inhibitor and its Potency in Combination with Diarylquinolines. Angew Chem Int Ed Engl 2020. [DOI: 10.1002/ange.202002546] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
Affiliation(s)
- Adam Hotra
- School of Physical and Mathematical Sciences Nanyang Technological University 21 Nanyang Link Singapore 637371 Republic of Singapore
- School of Biological Sciences Nanyang Technological University 60 Nanyang Drive Singapore 637551 Republic of Singapore
- Nanyang Institute of Technology in Health and Medicine Interdisciplinary Graduate School Nanyang Technological University Republic of Singapore
| | - Priya Ragunathan
- School of Biological Sciences Nanyang Technological University 60 Nanyang Drive Singapore 637551 Republic of Singapore
| | - Pearly Shuyi Ng
- Experimental Drug Development Centre Agency for Science Technology and Research, A*STAR 10 Biopolis Road Singapore 138670 Republic of Singapore
| | - Pattarakiat Seankongsuk
- School of Physical and Mathematical Sciences Nanyang Technological University 21 Nanyang Link Singapore 637371 Republic of Singapore
| | - Amaravadhi Harikishore
- School of Physical and Mathematical Sciences Nanyang Technological University 21 Nanyang Link Singapore 637371 Republic of Singapore
- School of Biological Sciences Nanyang Technological University 60 Nanyang Drive Singapore 637551 Republic of Singapore
| | - Jickky Palmae Sarathy
- Department of Microbiology and Immunology Yong Loo Lin School of Medicine National University of Singapore 14 Medical Drive Singapore 117599 Republic of Singapore
| | - Wuan‐Geok Saw
- School of Biological Sciences Nanyang Technological University 60 Nanyang Drive Singapore 637551 Republic of Singapore
| | - Umayal Lakshmanan
- Experimental Drug Development Centre Agency for Science Technology and Research, A*STAR 10 Biopolis Road Singapore 138670 Republic of Singapore
| | - Patcharaporn Sae‐Lao
- School of Physical and Mathematical Sciences Nanyang Technological University 21 Nanyang Link Singapore 637371 Republic of Singapore
| | - Nitin Pal Kalia
- Lee Kong Chian School of Medicine Nanyang Technological University Experimental Medicine Building Republic of Singapore
| | - Joon Shin
- School of Biological Sciences Nanyang Technological University 60 Nanyang Drive Singapore 637551 Republic of Singapore
| | - Revathy Kalyanasundaram
- Centre for Drug Discovery and Development Sathyabama Institute of Science and Technology Chennai 600119 India
| | - Sivaraj Anbarasu
- Centre for Drug Discovery and Development Sathyabama Institute of Science and Technology Chennai 600119 India
| | - Krupakar Parthasarathy
- Centre for Drug Discovery and Development Sathyabama Institute of Science and Technology Chennai 600119 India
| | - Chaudhari Namrata Pradeep
- School of Biological Sciences Nanyang Technological University 60 Nanyang Drive Singapore 637551 Republic of Singapore
| | - Harshyaa Makhija
- School of Biological Sciences Nanyang Technological University 60 Nanyang Drive Singapore 637551 Republic of Singapore
| | - Peter Dröge
- School of Biological Sciences Nanyang Technological University 60 Nanyang Drive Singapore 637551 Republic of Singapore
| | - Anders Poulsen
- Experimental Drug Development Centre Agency for Science Technology and Research, A*STAR 10 Biopolis Road Singapore 138670 Republic of Singapore
| | - Jocelyn Hui Ling Tan
- Experimental Drug Development Centre Agency for Science Technology and Research, A*STAR 10 Biopolis Road Singapore 138670 Republic of Singapore
| | - Kevin Pethe
- School of Biological Sciences Nanyang Technological University 60 Nanyang Drive Singapore 637551 Republic of Singapore
- Lee Kong Chian School of Medicine Nanyang Technological University Experimental Medicine Building Republic of Singapore
| | - Thomas Dick
- Department of Microbiology and Immunology Yong Loo Lin School of Medicine National University of Singapore 14 Medical Drive Singapore 117599 Republic of Singapore
- Center for Discovery and Innovation Hackensack Meridian Health 340 Kingsland Street Nutley NJ 07110 USA
| | - Roderick W. Bates
- School of Physical and Mathematical Sciences Nanyang Technological University 21 Nanyang Link Singapore 637371 Republic of Singapore
| | - Gerhard Grüber
- School of Biological Sciences Nanyang Technological University 60 Nanyang Drive Singapore 637551 Republic of Singapore
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22
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Chong SMS, Manimekalai MSS, Sarathy JP, Williams ZC, Harold LK, Cook GM, Dick T, Pethe K, Bates RW, Grüber G. Antituberculosis Activity of the Antimalaria Cytochrome bcc Oxidase Inhibitor SCR0911. ACS Infect Dis 2020; 6:725-737. [PMID: 32092260 DOI: 10.1021/acsinfecdis.9b00408] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
The ability to respire and generate adenosine triphosphate (ATP) is essential for the physiology, persistence, and pathogenicity of Mycobacterium tuberculosis, which causes tuberculosis. By employing a lead repurposing strategy, the malarial cytochrome bc1 inhibitor SCR0911 was tested against mycobacteria. Docking studies were carried out to reveal potential binding and to understand the binding interactions with the target, cytochrome bcc. Whole-cell-based and in vitro assays demonstrated the potency of SCR0911 by inhibiting cell growth and ATP synthesis in both the fast- and slow-growing M. smegmatis and M. bovis bacillus Calmette-Guérin, respectively. The variety of biochemical assays and the use of a cytochrome bcc deficient mutant strain validated the cytochrome bcc oxidase as the direct target of the drug. The data demonstrate the broad-spectrum activity of SCR0911 and open the door for structure-activity relationship studies to improve the potency of new mycobacteria specific SCR0911 analogues.
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Affiliation(s)
- Shi Min Sherilyn Chong
- School of Biological Sciences, Nanyang Technological University, 60 Nanyang Drive, Singapore 637551, Republic of Singapore
- School of Physical and Mathematical Sciences, Nanyang Technological University, 21 Nanyang Link, Singapore 637371, Republic of Singapore
- Nanyang Institute of Technology in Health and Medicine, Interdisciplinary Graduate School, Nanyang Technological University, Singapore 637551, Republic of Singapore
| | | | - Jickky Palmae Sarathy
- Department of Microbiology and Immunology, Yong Loo Lin School of Medicine, National University of Singapore, 14 Medical Drive, Singapore 117599, Republic of Singapore
| | - Zoe C. Williams
- Department of Microbiology and Immunology, School of Biomedical Sciences, University of Otago, Dunedin 9054, New Zealand
| | - Liam K. Harold
- Department of Microbiology and Immunology, School of Biomedical Sciences, University of Otago, Dunedin 9054, New Zealand
| | - Gregory M. Cook
- Department of Microbiology and Immunology, School of Biomedical Sciences, University of Otago, Dunedin 9054, New Zealand
| | - Thomas Dick
- Department of Microbiology and Immunology, Yong Loo Lin School of Medicine, National University of Singapore, 14 Medical Drive, Singapore 117599, Republic of Singapore
- Center for Discovery and Innovation, Hackensack Meridian Health, 340 Kingsland Street Building 102, Nutley, New Jersey 07110, United States
| | - Kevin Pethe
- School of Biological Sciences, Nanyang Technological University, 60 Nanyang Drive, Singapore 637551, Republic of Singapore
- Lee Kong Chian School of Medicine, Nanyang Technological University, Singapore 636921, Singapore
| | - Roderick W. Bates
- School of Physical and Mathematical Sciences, Nanyang Technological University, 21 Nanyang Link, Singapore 637371, Republic of Singapore
| | - Gerhard Grüber
- School of Biological Sciences, Nanyang Technological University, 60 Nanyang Drive, Singapore 637551, Republic of Singapore
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Oxidative Phosphorylation—an Update on a New, Essential Target Space for Drug Discovery in Mycobacterium tuberculosis. APPLIED SCIENCES-BASEL 2020. [DOI: 10.3390/app10072339] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
New drugs with new mechanisms of action are urgently required to tackle the global tuberculosis epidemic. Following the FDA-approval of the ATP synthase inhibitor bedaquiline (Sirturo®), energy metabolism has become the subject of intense focus as a novel pathway to exploit for tuberculosis drug development. This enthusiasm stems from the fact that oxidative phosphorylation (OxPhos) and the maintenance of the transmembrane electrochemical gradient are essential for the viability of replicating and non-replicating Mycobacterium tuberculosis (M. tb), the etiological agent of human tuberculosis (TB). Therefore, new drugs targeting this pathway have the potential to shorten TB treatment, which is one of the major goals of TB drug discovery. This review summarises the latest and key findings regarding the OxPhos pathway in M. tb and provides an overview of the inhibitors targeting various components. We also discuss the potential of new regimens containing these inhibitors, the flexibility of this pathway and, consequently, the complexity in targeting it. Lastly, we discuss opportunities and future directions of this drug target space.
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24
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Grüber G. Introduction: Novel insights into TB research and drug discovery. PROGRESS IN BIOPHYSICS AND MOLECULAR BIOLOGY 2020; 152:2-5. [PMID: 32087187 DOI: 10.1016/j.pbiomolbio.2020.02.003] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/27/2019] [Accepted: 02/06/2020] [Indexed: 12/24/2022]
Abstract
Mycobacterium tuberculosis (Mtb), the causative agent of tuberculosis (TB), kills more people than any other bacterium. TB control is threatened by the continued spread of drug resistance; multi-drug and extensively drug resistant Mtb require longer, more costly, treatment with multiple drugs causing worse side effects and have a lower likelihood of treatment success. The urgent need for better treatment options for drug resistant Mtb has led the World Health Organization to prioritize development of not only new individual antitubercular agents, but also new drug regimens. This introductory chapter of the special issue Novel insights into TB research and drug discovery within Progress in Biophysics and Molecular Biology, gives a short overview about the general problems of TB and the treatment of this disease today, and introduces the review topics within this issue.
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Affiliation(s)
- Gerhard Grüber
- Nanyang Technological University, School of Biological Sciences, 60 Nanyang Drive, Singapore, 637551, Republic of Singapore.
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25
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Harikishore A, Chong SSM, Ragunathan P, Bates RW, Grüber G. Targeting the menaquinol binding loop of mycobacterial cytochrome bd oxidase. Mol Divers 2020; 25:517-524. [PMID: 31939065 DOI: 10.1007/s11030-020-10034-0] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2019] [Accepted: 01/06/2020] [Indexed: 12/27/2022]
Abstract
Mycobacteria have shown enormous resilience to survive and persist by remodeling and altering metabolic requirements. Under stringent conditions or exposure to drugs, mycobacteria have adapted to rescue themselves by shutting down their major metabolic activity and elevate certain survival factor levels and efflux pathways to survive and evade the effects of drug treatments. A fundamental feature in this adaptation is the ability of mycobacteria to vary the enzyme composition of the electron transport chain (ETC), which generates the proton motive force for the synthesis of adenosine triphosphate via oxidative phosphorylation. Mycobacteria harbor dehydrogenases to fuel the ETC, and two terminal respiratory oxidases, an aa3-type cytochrome c oxidase (cyt-bcc-aa3) and a bacterial specific cytochrome bd-type menaquinol oxidase (cyt-bd). In this study, we employed homology modeling and structure-based virtual screening studies to target mycobacteria-specific residues anchoring the b558 menaquinol binding region of Mycobacterium tuberculosis cyt-bd oxidase to obtain a focused library. Furthermore, ATP synthesis inhibition assays were carried out. One of the ligands MQL-H2 inhibited both NADH2- and succinate-driven ATP synthesis inhibition of Mycobacterium smegmatis inside-out vesicles in micromolar potency. Similarly, MQL-H2 also inhibited NADH2-driven ATP synthesis in inside-out vesicles of the cytochrome-bcc oxidase deficient M. smegmatis strain. Since neither varying the electron donor substrates nor deletion of the cyt-bcc oxidase, a major source of protons, hindered the inhibitory effects of the MQL-H2, reflecting that MQL-H2 targets the terminal oxidase cytochrome bd oxidase, which was consistent with molecular docking studies. Characterization of novel cytochrome bd oxidase Menaquinol binding domain inhibitor (MQL-H2) using virtual screening and ATP synthesis inhibition assays.
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Affiliation(s)
- Amaravadhi Harikishore
- Division of Chemistry and Biological Chemistry, School of Physical and Mathematical Sciences, Nanyang Technological University, 21 Nanyang Link, Singapore, 637371, Republic of Singapore
| | - Sherilyn Shi Min Chong
- Division of Chemistry and Biological Chemistry, School of Physical and Mathematical Sciences, Nanyang Technological University, 21 Nanyang Link, Singapore, 637371, Republic of Singapore
- School of Biological Sciences, Nanyang Technological University, 60 Nanyang Drive, Singapore, 637551, Republic of Singapore
- Nanyang Institute of Technology in Health and Medicine, Interdisciplinary Graduate School, Nanyang Technological University, Singapore, Republic of Singapore
| | - Priya Ragunathan
- School of Biological Sciences, Nanyang Technological University, 60 Nanyang Drive, Singapore, 637551, Republic of Singapore
| | - Roderick W Bates
- Division of Chemistry and Biological Chemistry, School of Physical and Mathematical Sciences, Nanyang Technological University, 21 Nanyang Link, Singapore, 637371, Republic of Singapore
| | - Gerhard Grüber
- School of Biological Sciences, Nanyang Technological University, 60 Nanyang Drive, Singapore, 637551, Republic of Singapore.
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Saw WG, Wong CF, Dick T, Grüber G. Overexpression, purification, enzymatic and microscopic characterization of recombinant mycobacterial F-ATP synthase. Biochem Biophys Res Commun 2019; 522:374-380. [PMID: 31761325 DOI: 10.1016/j.bbrc.2019.11.098] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2019] [Accepted: 11/15/2019] [Indexed: 01/16/2023]
Abstract
The F-ATP synthase is an essential enzyme in mycobacteria, including the pathogenic Mycobacterium tuberculosis. Several new compounds in the TB-drug pipeline target the F-ATP synthase. In light of the importance and pharmacological attractiveness of this novel antibiotic target, tools have to be developed to generate a recombinant mycobacterial F1FO ATP synthase to achieve atomic insight and mutants for mechanistic and regulatory understanding as well as structure-based drug design. Here, we report the first genetically engineered, purified and enzymatically active recombinant M. smegmatis F1FO ATP synthase. The projected 2D- and 3D structures of the recombinant enzyme derived from negatively stained electron micrographs are presented. Furthermore, the first 2D projections from cryo-electron images are revealed, paving the way for an atomic resolution structure determination.
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Affiliation(s)
- Wuan-Geok Saw
- Nanyang Technological University, School of Biological Sciences, 60 Nanyang Drive, Singapore, 637551, Republic of Singapore
| | - Chui-Fann Wong
- Nanyang Technological University, School of Biological Sciences, 60 Nanyang Drive, Singapore, 637551, Republic of Singapore
| | - Thomas Dick
- Center for Discovery and Innovation, Hackensack Meridian Health, Nutley, NJ, USA; Department of Microbiology and Immunology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Republic of Singapore
| | - Gerhard Grüber
- Nanyang Technological University, School of Biological Sciences, 60 Nanyang Drive, Singapore, 637551, Republic of Singapore.
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Unique structural and mechanistic properties of mycobacterial F-ATP synthases: Implications for drug design. PROGRESS IN BIOPHYSICS AND MOLECULAR BIOLOGY 2019; 152:64-73. [PMID: 31743686 DOI: 10.1016/j.pbiomolbio.2019.11.006] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Received: 08/21/2019] [Revised: 09/25/2019] [Accepted: 11/13/2019] [Indexed: 12/31/2022]
Abstract
The causative agent of Tuberculosis (TB) Mycobacterium tuberculosis (Mtb) encounters unfavourable environmental conditions in the lungs, including nutrient limitation, low oxygen tensions and/or low/high pH values. These harsh conditions in the host triggers Mtb to enter a dormant state in which the pathogen does not replicate and uses host-derived fatty acids instead of carbohydrates as an energy source. Independent to the energy source, the bacterium's energy currency ATP is generated by oxidative phosphorylation, in which the F1FO-ATP synthase uses the proton motive force generated by the electron transport chain. This catalyst is essential in Mtb and inhibition by the diarylquinoline class of drugs like Bedaquilline, TBAJ-587, TBAJ-876 or squaramides demonstrated that this engine is an attractive target in TB drug discovery. A special feature of the mycobacterial F-ATP synthase is its inability to establish a significant proton gradient during ATP hydrolysis, and its latent ATPase activity, to prevent energy waste and to control the membrane potential. Recently, unique epitopes of mycobacterial F1FO-ATP synthase subunits absent in their prokaryotic or mitochondrial counterparts have been identified to contribute to the regulation of the low ATPase activity. Most recent structural insights into individual subunits, the F1 domain or the entire mycobacterial enzyme added to the understanding of mechanisms, regulation and differences of the mycobacterial F1FO-ATP synthase compared to other bacterial and eukaryotic engines. These novel insights provide the basis for the design of new compounds targeting this engine and even novel regimens for multidrug resistant TB.
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Disrupting coupling within mycobacterial F-ATP synthases subunit ε causes dysregulated energy production and cell wall biosynthesis. Sci Rep 2019; 9:16759. [PMID: 31727946 PMCID: PMC6856130 DOI: 10.1038/s41598-019-53107-3] [Citation(s) in RCA: 28] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2019] [Accepted: 10/28/2019] [Indexed: 11/23/2022] Open
Abstract
The dynamic interaction of the N- and C-terminal domains of mycobacterial F-ATP synthase subunit ε is proposed to contribute to efficient coupling of H+-translocation and ATP synthesis. Here, we investigate crosstalk between both subunit ε domains by introducing chromosomal atpC missense mutations in the C-terminal helix 2 of ε predicted to disrupt inter domain and subunit ε-α crosstalk and therefore coupling. The ε mutant εR105A,R111A,R113A,R115A (ε4A) showed decreased intracellular ATP, slower growth rates and lower molar growth yields on non-fermentable carbon sources. Cellular respiration and metabolism were all accelerated in the mutant strain indicative of dysregulated oxidative phosphorylation. The ε4A mutant exhibited an altered colony morphology and was hypersusceptible to cell wall-acting antimicrobials suggesting defective cell wall biosynthesis. In silico screening identified a novel mycobacterial F-ATP synthase inhibitor disrupting ε’s coupling activity demonstrating the potential to advance this regulation as a new area for mycobacterial F-ATP synthase inhibitor development.
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TBAJ-876 Retains Bedaquiline's Activity against Subunits c and ε of Mycobacterium tuberculosis F-ATP Synthase. Antimicrob Agents Chemother 2019; 63:AAC.01191-19. [PMID: 31358589 PMCID: PMC6761534 DOI: 10.1128/aac.01191-19] [Citation(s) in RCA: 36] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2019] [Accepted: 07/25/2019] [Indexed: 12/18/2022] Open
Abstract
The antituberculosis drug bedaquiline (BDQ) inhibits Mycobacterium tuberculosis F-ATP synthase by interfering with two subunits. Drug binding to the c subunit stalls the rotation of the c ring, while binding to the ε subunit blocks coupling of c ring rotation to ATP synthesis at the catalytic α3:β3 headpiece. BDQ is used for the treatment of drug-resistant tuberculosis. The antituberculosis drug bedaquiline (BDQ) inhibits Mycobacterium tuberculosis F-ATP synthase by interfering with two subunits. Drug binding to the c subunit stalls the rotation of the c ring, while binding to the ε subunit blocks coupling of c ring rotation to ATP synthesis at the catalytic α3:β3 headpiece. BDQ is used for the treatment of drug-resistant tuberculosis. However, the drug is highly lipophilic, displays a long terminal half-life, and has a cardiotoxicity liability by causing QT interval prolongation. Recent medicinal chemistry campaigns have resulted in the discovery of 3,5-dialkoxypyridine analogues of BDQ that are less lipophilic, have higher clearance, and display lower cardiotoxic potential. TBAJ-876, which is a new developmental compound of this series, shows attractive antitubercular activity and efficacy in a murine tuberculosis model. Here, we asked whether TBAJ-876 and selected analogues of the compound retain BDQ’s mechanism of action. Biochemical assays showed that TBAJ-876 is a potent inhibitor of mycobacterial F-ATP synthase. Selection of spontaneous TBAJ-876-resistant mutants identified missense mutations at BDQ’s binding site on the c subunit, suggesting that TBAJ-876 retains BDQ’s targeting of the c ring. Susceptibility testing against a strain overexpressing the ε subunit and a strain harboring an engineered mutation in BDQ’s ε subunit binding site suggest that TBAJ-876 retains BDQ’s activity on the ε subunit. Nuclear magnetic resonance (NMR) titration studies confirmed that TBAJ-876 binds to the ε subunit at BDQ’s binding site. We show that TBAJ-876 retains BDQ’s antimycobacterial mode of action. The developmental compound inhibits the mycobacterial F-ATP synthase via a dual-subunit mechanism of interfering with the functions of both the enzyme’s c and ε subunits.
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30
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Kamariah N, Huber RG, Nartey W, Bhushan S, Bond PJ, Grüber G. Structure and subunit arrangement of Mycobacterial F1FO ATP synthase and novel features of the unique mycobacterial subunit δ. J Struct Biol 2019; 207:199-208. [DOI: 10.1016/j.jsb.2019.05.008] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2019] [Revised: 05/21/2019] [Accepted: 05/23/2019] [Indexed: 02/08/2023]
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31
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Bogdanović N, Trifunović D, Sielaff H, Westphal L, Bhushan S, Müller V, Grüber G. The structural features of Acetobacterium woodii F-ATP synthase reveal the importance of the unique subunit γ-loop in Na + translocation and ATP synthesis. FEBS J 2019; 286:1894-1907. [PMID: 30791207 DOI: 10.1111/febs.14793] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2018] [Revised: 01/25/2019] [Accepted: 02/18/2019] [Indexed: 12/18/2022]
Abstract
The Na+ translocating F1 FO ATP synthase from Acetobacterium woodii shows a subunit stoichiometry of α3 :β3 :γ:δ:ε:a:b2 :(c2/3 )9 :c1 and reveals an evolutionary path between synthases and pumps involving adaptations in the rotor c-ring, which is composed of F- and vacuolar-type c subunits in a stoichiometry of 9 : 1. This hybrid turbine couples rotation with Na+ translocation in the FO part and rotation of the central stalk subunits γ-ε to drive ATP synthesis in the catalytic α3 :β3 headpiece. Here, we isolated a highly pure recombinant A. woodii F-ATP synthase and present the first projected structure of this hybrid engine as determined by negative-stain electron microscopy and single-particle analysis. The uniqueness of the A. woodii F-ATP synthase is also reflected by an extra 17 amino acid residues loop (195 TSGKVKITEETKEEKSK211 ) in subunit γ. Deleting the loop-encoding DNA sequence (γΔ195-211 ) and purifying the recombinant F-ATP synthase γΔ195-211 mutant provided a platform to study its effect in enzyme stability and activity. The recombinant F-ATP synthase γΔ195-211 mutant revealed the same subunit composition as the wild-type enzyme and a minor reduction in ATP hydrolysis. When reconstituted into proteoliposomes ATP synthesis and Na+ transport were diminished, demonstrating the importance of the γ195-211 loop in both enzymatic processes. Based on a structural model, a coupling mechanism for this enzyme is proposed, highlighting the role of the γ-loop. Finally, the γ195-211 loop of A. woodii is discussed in comparison with the extra γ-loops of mycobacterial and chloroplasts F-ATP synthases described to be involved in species-specific regulatory mechanisms.
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Affiliation(s)
- Nebojša Bogdanović
- Nanyang Technological University, School of Biological Sciences, Singapore City, Singapore
| | - Dragan Trifunović
- Molecular Microbiology & Bioenergetics, Institute of Molecular Biosciences, Johann Wolfgang Goethe University Frankfurt/Main, Germany
| | - Hendrik Sielaff
- Nanyang Technological University, School of Biological Sciences, Singapore City, Singapore
| | - Lars Westphal
- Molecular Microbiology & Bioenergetics, Institute of Molecular Biosciences, Johann Wolfgang Goethe University Frankfurt/Main, Germany
| | - Shashi Bhushan
- Nanyang Technological University, School of Biological Sciences, Singapore City, Singapore.,NTU Institute of Structural Biology, Nanyang Technological University, Singapore City, Singapore
| | - Volker Müller
- Molecular Microbiology & Bioenergetics, Institute of Molecular Biosciences, Johann Wolfgang Goethe University Frankfurt/Main, Germany
| | - Gerhard Grüber
- Nanyang Technological University, School of Biological Sciences, Singapore City, Singapore
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32
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Vestergaard M, Ingmer H. Antibacterial and antifungal properties of resveratrol. Int J Antimicrob Agents 2019; 53:716-723. [PMID: 30825504 DOI: 10.1016/j.ijantimicag.2019.02.015] [Citation(s) in RCA: 201] [Impact Index Per Article: 40.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2018] [Revised: 02/13/2019] [Accepted: 02/16/2019] [Indexed: 12/30/2022]
Abstract
Resveratrol is a naturally occurring polyphenolic antioxidant that has received massive attention for its potential health benefits, including anticarcinogenesis, anti-aging and antimicrobial properties. The compound is well tolerated by humans and in recent years has been widely used as a nutraceutical. Its common use makes it interesting to investigate with respect to antimicrobial properties both as a single agent and in combination with conventional antibiotics. Resveratrol displays antimicrobial activity against a surprisingly wide range of bacterial, viral and fungal species. At subinhibitory concentrations, resveratrol can alter bacterial expression of virulence traits leading to reduced toxin production, inhibition of biofilm formation, reduced motility and interference with quorum sensing. In combination with conventional antibiotics, resveratrol enhances the activity of aminoglycosides against Staphylococcus aureus, whereas it antagonises the lethal activity of fluoroquinolones against S. aureus and Escherichia coli. Whilst the antimicrobial properties of the compound have been extensively studied in vitro, little is known about its efficacy in vivo. Nonetheless, following topical application resveratrol has alleviated acne lesions caused by the bacterium Propionibacterium acnes. There are currently no in vivo studies addressing its effect in combination with antibiotics, but recent research suggests that there may be a potential for enhancing the antimicrobial efficacy of certain existing antibiotic classes in combination with resveratrol. Given the difficulties associated with introducing new antimicrobial agents to the market, nutraceuticals such as resveratrol may prove to be interesting candidates when searching for solutions for the growing problem of antimicrobial resistance.
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Affiliation(s)
- Martin Vestergaard
- Department of Veterinary and Animal Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Stigbøjlen 4, DK-1870 Frederiksberg C, Denmark
| | - Hanne Ingmer
- Department of Veterinary and Animal Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Stigbøjlen 4, DK-1870 Frederiksberg C, Denmark.
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33
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Lapashina AS, Feniouk BA. ADP-Inhibition of H+-F OF 1-ATP Synthase. BIOCHEMISTRY (MOSCOW) 2018; 83:1141-1160. [PMID: 30472953 DOI: 10.1134/s0006297918100012] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
H+-FOF1-ATP synthase (F-ATPase, F-type ATPase, FOF1 complex) catalyzes ATP synthesis from ADP and inorganic phosphate in eubacteria, mitochondria, chloroplasts, and some archaea. ATP synthesis is powered by the transmembrane proton transport driven by the proton motive force (PMF) generated by the respiratory or photosynthetic electron transport chains. When the PMF is decreased or absent, ATP synthase catalyzes the reverse reaction, working as an ATP-dependent proton pump. The ATPase activity of the enzyme is regulated by several mechanisms, of which the most conserved is the non-competitive inhibition by the MgADP complex (ADP-inhibition). When ADP binds to the catalytic site without phosphate, the enzyme may undergo conformational changes that lock bound ADP, resulting in enzyme inactivation. PMF can induce release of inhibitory ADP and reactivate ATP synthase; the threshold PMF value required for enzyme reactivation might exceed the PMF for ATP synthesis. Moreover, membrane energization increases the catalytic site affinity to phosphate, thereby reducing the probability of ADP binding without phosphate and preventing enzyme transition to the ADP-inhibited state. Besides phosphate, oxyanions (e.g., sulfite and bicarbonate), alcohols, lauryldimethylamine oxide, and a number of other detergents can weaken ADP-inhibition and increase ATPase activity of the enzyme. In this paper, we review the data on ADP-inhibition of ATP synthases from different organisms and discuss the in vivo role of this phenomenon and its relationship with other regulatory mechanisms, such as ATPase activity inhibition by subunit ε and nucleotide binding in the noncatalytic sites of the enzyme. It should be noted that in Escherichia coli enzyme, ADP-inhibition is relatively weak and rather enhanced than prevented by phosphate.
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Affiliation(s)
- A S Lapashina
- Lomonosov Moscow State University, Faculty of Bioengineering and Bioinformatics, Moscow, 119991, Russia.,Belozersky Institute of Physico-Chemical Biology, Lomonosov Moscow State University, Moscow, 119991, Russia
| | - B A Feniouk
- Lomonosov Moscow State University, Faculty of Bioengineering and Bioinformatics, Moscow, 119991, Russia. .,Belozersky Institute of Physico-Chemical Biology, Lomonosov Moscow State University, Moscow, 119991, Russia
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Bogdanović N, Sundararaman L, Kamariah N, Tyagi A, Bhushan S, Ragunathan P, Shin J, Dick T, Grüber G. Structure and function of Mycobacterium-specific components of F-ATP synthase subunits α and ε. J Struct Biol 2018; 204:420-434. [PMID: 30342092 DOI: 10.1016/j.jsb.2018.10.006] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2018] [Revised: 10/08/2018] [Accepted: 10/16/2018] [Indexed: 01/21/2023]
Abstract
The Mycobacterium tuberculosis (Mtb) F1FO-ATP synthase (α3:β3:γ:δ:ε:a:b:b':c9) is an essential enzyme that supplies energy for both the aerobic growing and the hypoxic dormant stage of the mycobacterial life cycle. Employing the heterologous F-ATP synthase model system αchi3:β3:γ we showed previously, that transfer of the C-terminal domain (CTD) of Mtb subunit α (Mtα514-549) to a standard F-ATP synthase α subunit suppresses ATPase activity. Here we determined the 3D reconstruction from electron micrographs of the αchi3:β3:γ complex reconstituted with the Mtb subunit ε (Mtε), which has been shown to crosstalk with the CTD of Mtα. Together with the first solution shape of Mtb subunit α (Mtα), derived from solution X-ray scattering, the structural data visualize the extended C-terminal stretch of the mycobacterial subunit α. In addition, Mtε mutants MtεR62L, MtεE87A, Mtε6-121, and Mtε1-120, reconstituted with αchi3:β3:γ provided insight into their role in coupling and in trapping inhibiting MgADP. NMR solution studies of MtεE87A gave insights into how this residue contributes to stability and crosstalk between the N-terminal domain (NTD) and the CTD of Mtε. Analyses of the N-terminal mutant Mtε6-121 highlight the differences of the NTD of mycobacterial subunit ε to the well described Geobacillus stearothermophilus or Escherichia coli counterparts. These data are discussed in context of a crosstalk between the very N-terminal amino acids of Mtε and the loop region of one c subunit of the c-ring turbine for coupling of proton-translocation and ATP synthesis activity.
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Affiliation(s)
- Nebojša Bogdanović
- Nanyang Technological University, School of Biological Sciences, 60 Nanyang Drive, Singapore 637551, Republic of Singapore
| | - Lavanya Sundararaman
- Nanyang Technological University, School of Biological Sciences, 60 Nanyang Drive, Singapore 637551, Republic of Singapore
| | - Neelagandan Kamariah
- Nanyang Technological University, School of Biological Sciences, 60 Nanyang Drive, Singapore 637551, Republic of Singapore
| | - Anu Tyagi
- Nanyang Technological University, School of Biological Sciences, 60 Nanyang Drive, Singapore 637551, Republic of Singapore
| | - Shashi Bhushan
- Nanyang Technological University, School of Biological Sciences, 60 Nanyang Drive, Singapore 637551, Republic of Singapore; NTU Institute of Structural Biology, Nanyang Technological University, Republic of Singapore
| | - Priya Ragunathan
- Nanyang Technological University, School of Biological Sciences, 60 Nanyang Drive, Singapore 637551, Republic of Singapore
| | - Joon Shin
- Nanyang Technological University, School of Biological Sciences, 60 Nanyang Drive, Singapore 637551, Republic of Singapore
| | - Thomas Dick
- Department of Microbiology and Immunology, Yong Loo Lin School of Medicine, National University of Singapore, 14 Medical Drive, Singapore 117599, Republic of Singapore; Public Health Research Institute, New Jersey Medical School, Rutgers, The State University of New Jersey, 225 Warren Street, Newark, NJ 07103, USA
| | - Gerhard Grüber
- Nanyang Technological University, School of Biological Sciences, 60 Nanyang Drive, Singapore 637551, Republic of Singapore.
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Nøhr-Meldgaard K, Ovsepian A, Ingmer H, Vestergaard M. Resveratrol enhances the efficacy of aminoglycosides against Staphylococcus aureus. Int J Antimicrob Agents 2018; 52:390-396. [PMID: 29906565 DOI: 10.1016/j.ijantimicag.2018.06.005] [Citation(s) in RCA: 27] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2018] [Revised: 04/17/2018] [Accepted: 06/02/2018] [Indexed: 01/04/2023]
Abstract
Development of new antibiotics is costly and time-consuming, and therefore increasing the efficacy of conventional antibiotics is extremely attractive. For the human pathogen, Staphylococcus aureus, inactivation of the ATP synthase increases its susceptibility to gentamicin (an aminoglycoside) 16-fold. Aminoglycosides are rarely used as monotherapy against S. aureus due to the risk of development of resistance and toxic effects. This study explored the possibility of enhancing the efficacy of aminoglycosides against S. aureus and other Gram-positive pathogens by inhibiting the ATP synthase with resveratrol, a polyphenolic ATP synthase inhibitor that is commonly used as a dietary supplement. Co-administration of subinhibitory concentrations of resveratrol increased the activity of aminoglycosides, including gentamicin, kanamycin, neomycin, streptomycin and tobramycin, up to 32-fold against S. aureus, while the effect was lower (2-4-fold reduction in minimum inhibitory concentration) for other Gram-positive pathogens (i.e. Staphylococcus epidermidis, Enterococcus faecium and Enterococcus faecalis). The mechanism by which resveratrol increases the efficacy of aminoglycosides appears to be unrelated to membrane hyperpolarization and disruption of membrane integrity, which have been associated previously with increased aminoglycoside susceptibility. These results demonstrate that inhibition of the ATP synthase increases the efficacy of aminoglycosides against important Gram-positive pathogens, and the ATP synthase should be explored further as a target that may extend the clinical applicability of aminoglycosides.
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Affiliation(s)
- Katrine Nøhr-Meldgaard
- Department of Veterinary and Animal Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Frederiksberg, Denmark
| | - Armen Ovsepian
- Department of Veterinary and Animal Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Frederiksberg, Denmark
| | - Hanne Ingmer
- Department of Veterinary and Animal Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Frederiksberg, Denmark.
| | - Martin Vestergaard
- Department of Veterinary and Animal Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Frederiksberg, Denmark
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36
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Krah A, Zarco-Zavala M, McMillan DGG. Insights into the regulatory function of the ɛ subunit from bacterial F-type ATP synthases: a comparison of structural, biochemical and biophysical data. Open Biol 2018; 8:170275. [PMID: 29769322 PMCID: PMC5990651 DOI: 10.1098/rsob.170275] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2017] [Accepted: 04/24/2018] [Indexed: 01/07/2023] Open
Abstract
ATP synthases catalyse the formation of ATP, the most common chemical energy storage unit found in living cells. These enzymes are driven by an electrochemical ion gradient, which allows the catalytic evolution of ATP by a binding change mechanism. Most ATP synthases are capable of catalysing ATP hydrolysis to varying degrees, and to prevent wasteful ATP hydrolysis, bacteria and mitochondria have regulatory mechanisms such as ADP inhibition. Additionally, ɛ subunit inhibition has also been described in three bacterial systems, Escherichia coli, Bacillus PS3 and Caldalkalibacillus thermarum TA2.A1. Previous studies suggest that the ɛ subunit is capable of undergoing an ATP-dependent conformational change from the ATP hydrolytic inhibitory 'extended' conformation to the ATP-induced non-inhibitory 'hairpin' conformation. A recently published crystal structure of the F1 domain of the C. thermarum TA2.A1 F1Fo ATP synthase revealed a mutant ɛ subunit lacking the ability to bind ATP in a hairpin conformation. This is a surprising observation considering it is an organism that performs no ATP hydrolysis in vivo, and appears to challenge the current dogma on the regulatory role of the ɛ subunit. This has prompted a re-examination of present knowledge of the ɛ subunits role in different organisms. Here, we compare published biochemical, biophysical and structural data involving ɛ subunit-mediated ATP hydrolysis regulation in a variety of organisms, concluding that the ɛ subunit from the bacterial F-type ATP synthases is indeed capable of regulating ATP hydrolysis activity in a wide variety of bacteria, making it a potentially valuable drug target, but its exact role is still under debate.
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Affiliation(s)
- Alexander Krah
- School of Computational Sciences, Korea Institute for Advanced Study, 85 Hoegiro Dongdaemun-gu, Seoul 02455, Republic of Korea
| | - Mariel Zarco-Zavala
- Department of Applied Chemistry, Graduate School of Engineering, The University of Tokyo, Tokyo 113-8656, Japan
| | - Duncan G G McMillan
- Department of Biotechnology, Delft University of Technology, van der Maasweg 9, Delft 2629 HZ, The Netherlands
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37
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Iqbal IK, Bajeli S, Akela AK, Kumar A. Bioenergetics of Mycobacterium: An Emerging Landscape for Drug Discovery. Pathogens 2018; 7:E24. [PMID: 29473841 PMCID: PMC5874750 DOI: 10.3390/pathogens7010024] [Citation(s) in RCA: 36] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2018] [Revised: 01/29/2018] [Accepted: 01/31/2018] [Indexed: 11/16/2022] Open
Abstract
Mycobacterium tuberculosis (Mtb) exhibits remarkable metabolic flexibility that enables it to survive a plethora of host environments during its life cycle. With the advent of bedaquiline for treatment of multidrug-resistant tuberculosis, oxidative phosphorylation has been validated as an important target and a vulnerable component of mycobacterial metabolism. Exploiting the dependence of Mtb on oxidative phosphorylation for energy production, several components of this pathway have been targeted for the development of new antimycobacterial agents. This includes targeting NADH dehydrogenase by phenothiazine derivatives, menaquinone biosynthesis by DG70 and other compounds, terminal oxidase by imidazopyridine amides and ATP synthase by diarylquinolines. Importantly, oxidative phosphorylation also plays a critical role in the survival of persisters. Thus, inhibitors of oxidative phosphorylation can synergize with frontline TB drugs to shorten the course of treatment. In this review, we discuss the oxidative phosphorylation pathway and development of its inhibitors in detail.
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Affiliation(s)
- Iram Khan Iqbal
- Council of Scientific and Industrial Research, Institute of Microbial Technology, Chandigarh 160036, India.
| | - Sapna Bajeli
- Council of Scientific and Industrial Research, Institute of Microbial Technology, Chandigarh 160036, India.
| | - Ajit Kumar Akela
- Council of Scientific and Industrial Research, Institute of Microbial Technology, Chandigarh 160036, India.
| | - Ashwani Kumar
- Council of Scientific and Industrial Research, Institute of Microbial Technology, Chandigarh 160036, India.
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38
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Joon S, Ragunathan P, Sundararaman L, Nartey W, Kundu S, Manimekalai MSS, Bogdanović N, Dick T, Grüber G. The NMR solution structure of Mycobacterium tuberculosis F-ATP synthase subunit ε provides new insight into energy coupling inside the rotary engine. FEBS J 2018; 285:1111-1128. [PMID: 29360236 DOI: 10.1111/febs.14392] [Citation(s) in RCA: 34] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2017] [Revised: 11/30/2017] [Accepted: 01/18/2018] [Indexed: 11/27/2022]
Abstract
Mycobacterium tuberculosis (Mt) F1 F0 ATP synthase (α3 :β3 :γ:δ:ε:a:b:b':c9 ) is essential for the viability of growing and nongrowing persister cells of the pathogen. Here, we present the first NMR solution structure of Mtε, revealing an N-terminal β-barrel domain (NTD) and a C-terminal domain (CTD) composed of a helix-loop-helix with helix 1 and -2 being shorter compared to their counterparts in other bacteria. The C-terminal amino acids are oriented toward the NTD, forming a domain-domain interface between the NTD and CTD. The Mtε structure provides a novel mechanistic model of coupling c-ring- and ε rotation via a patch of hydrophobic residues in the NTD and residues of the CTD to the bottom of the catalytic α3 β3 -headpiece. To test our model, genome site-directed mutagenesis was employed to introduce amino acid changes in these two parts of the epsilon subunit. Inverted vesicle assays show that these mutations caused an increase in ATP hydrolysis activity and a reduction in ATP synthesis. The structural and enzymatic data are discussed in light of the transition mechanism of a compact and extended state of Mtε, which provides the inhibitory effects of this coupling subunit inside the rotary engine. Finally, the employment of these data with molecular docking shed light into the second binding site of the drug Bedaquiline. DATABASE Structural data are available in the PDB under the accession number 5YIO.
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Affiliation(s)
- Shin Joon
- Nanyang Technological University, School of Biological Sciences, Singapore, Singapore
| | - Priya Ragunathan
- Nanyang Technological University, School of Biological Sciences, Singapore, Singapore
| | - Lavanya Sundararaman
- Nanyang Technological University, School of Biological Sciences, Singapore, Singapore
| | - Wilson Nartey
- Nanyang Technological University, School of Biological Sciences, Singapore, Singapore
| | - Subhashri Kundu
- Department of Microbiology and Immunology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore
| | | | - Nebojša Bogdanović
- Nanyang Technological University, School of Biological Sciences, Singapore, Singapore
| | - Thomas Dick
- Department of Microbiology and Immunology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore.,Public Health Research Institute, New Jersey Medical School, Rutgers, The State University of New Jersey, Newark, NJ, USA
| | - Gerhard Grüber
- Nanyang Technological University, School of Biological Sciences, Singapore, Singapore
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39
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Ragunathan P, Sielaff H, Sundararaman L, Biuković G, Subramanian Manimekalai MS, Singh D, Kundu S, Wohland T, Frasch W, Dick T, Grüber G. The uniqueness of subunit α of mycobacterial F-ATP synthases: An evolutionary variant for niche adaptation. J Biol Chem 2017; 292:11262-11279. [PMID: 28495884 PMCID: PMC5500794 DOI: 10.1074/jbc.m117.784959] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2017] [Revised: 05/11/2017] [Indexed: 01/30/2023] Open
Abstract
The F1F0 -ATP (F-ATP) synthase is essential for growth of Mycobacterium tuberculosis, the causative agent of tuberculosis (TB). In addition to their synthase function most F-ATP synthases possess an ATP-hydrolase activity, which is coupled to proton-pumping activity. However, the mycobacterial enzyme lacks this reverse activity, but the reason for this deficiency is unclear. Here, we report that a Mycobacterium-specific, 36-amino acid long C-terminal domain in the nucleotide-binding subunit α (Mtα) of F-ATP synthase suppresses its ATPase activity and determined the mechanism of suppression. First, we employed vesicles to show that in intact membrane-embedded mycobacterial F-ATP synthases deletion of the C-terminal domain enabled ATPase and proton-pumping activity. We then generated a heterologous F-ATP synthase model system, which demonstrated that transfer of the mycobacterial C-terminal domain to a standard F-ATP synthase α subunit suppresses ATPase activity. Single-molecule rotation assays indicated that the introduction of this Mycobacterium-specific domain decreased the angular velocity of the power-stroke after ATP binding. Solution X-ray scattering data and NMR results revealed the solution shape of Mtα and the 3D structure of the subunit α C-terminal peptide 521PDEHVEALDEDKLAKEAVKV540 of M. tubercolosis (Mtα(521-540)), respectively. Together with cross-linking studies, the solution structural data lead to a model, in which Mtα(521-540) comes in close proximity with subunit γ residues 104-109, whose interaction may influence the rotation of the camshaft-like subunit γ. Finally, we propose that the unique segment Mtα(514-549), which is accessible at the C terminus of mycobacterial subunit α, is a promising drug epitope.
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Affiliation(s)
- Priya Ragunathan
- From the Nanyang Technological University, School of Biological Sciences, 60 Nanyang Drive, Singapore 637551, Republic of Singapore
| | - Hendrik Sielaff
- From the Nanyang Technological University, School of Biological Sciences, 60 Nanyang Drive, Singapore 637551, Republic of Singapore
| | - Lavanya Sundararaman
- From the Nanyang Technological University, School of Biological Sciences, 60 Nanyang Drive, Singapore 637551, Republic of Singapore
| | - Goran Biuković
- the Department of Microbiology and Immunology, National University of Singapore, Yong Loo Lin School of Medicine, 14 Medical Drive, Singapore 117599, Republic of Singapore
| | | | - Dhirendra Singh
- From the Nanyang Technological University, School of Biological Sciences, 60 Nanyang Drive, Singapore 637551, Republic of Singapore
| | - Subhashri Kundu
- the Department of Microbiology and Immunology, National University of Singapore, Yong Loo Lin School of Medicine, 14 Medical Drive, Singapore 117599, Republic of Singapore
| | - Thorsten Wohland
- the Departments of Biological Sciences and Chemistry and NUS Centre for Bioimaging Sciences (CBIS), National University of Singapore, 14 Science Drive 4, Singapore 117557, Republic of Singapore, and
| | - Wayne Frasch
- School of Life Sciences, Arizona State University, Tempe, Arizona 85287
| | - Thomas Dick
- the Department of Microbiology and Immunology, National University of Singapore, Yong Loo Lin School of Medicine, 14 Medical Drive, Singapore 117599, Republic of Singapore
| | - Gerhard Grüber
- From the Nanyang Technological University, School of Biological Sciences, 60 Nanyang Drive, Singapore 637551, Republic of Singapore,
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40
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Abstract
Mycobacterium tuberculosis (M. tuberculosis), the causative agent of tuberculosis, uses various tactics to resist on antibiotics and evade host immunity. To control tuberculosis, antibiotics with novel mechanisms of action are urgently needed. Emerging new antibiotics and underlying novel drug targets are summarized in this paper.
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Affiliation(s)
- Nzungize Lambert
- a Institute of Modern Biopharmaceuticals, State Key Laboratory Breeding Base of Eco-Environment and Bio-Resource of the Three Gorges Area, Key Laboratory of Ministry of Education Eco-Environment of the Three Gorges Reservoir Region, School of Life Sciences, Southwest University , Chongqing , China
| | - Abualgasim Elgaili Abdalla
- a Institute of Modern Biopharmaceuticals, State Key Laboratory Breeding Base of Eco-Environment and Bio-Resource of the Three Gorges Area, Key Laboratory of Ministry of Education Eco-Environment of the Three Gorges Reservoir Region, School of Life Sciences, Southwest University , Chongqing , China.,b Department of Clinical Microbiology, College of Medical Laboratory Sciences, Omdurman , Islamic University , Omdurman , Sudan
| | - Xiangke Duan
- a Institute of Modern Biopharmaceuticals, State Key Laboratory Breeding Base of Eco-Environment and Bio-Resource of the Three Gorges Area, Key Laboratory of Ministry of Education Eco-Environment of the Three Gorges Reservoir Region, School of Life Sciences, Southwest University , Chongqing , China
| | - Jianping Xie
- a Institute of Modern Biopharmaceuticals, State Key Laboratory Breeding Base of Eco-Environment and Bio-Resource of the Three Gorges Area, Key Laboratory of Ministry of Education Eco-Environment of the Three Gorges Reservoir Region, School of Life Sciences, Southwest University , Chongqing , China
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41
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Bedaquiline Targets the ε Subunit of Mycobacterial F-ATP Synthase. Antimicrob Agents Chemother 2016; 60:6977-6979. [PMID: 27620476 PMCID: PMC5075122 DOI: 10.1128/aac.01291-16] [Citation(s) in RCA: 49] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2016] [Accepted: 09/04/2016] [Indexed: 12/24/2022] Open
Abstract
The tuberculosis drug bedaquiline inhibits mycobacterial F-ATP synthase by binding to its c subunit. Using the purified ε subunit of the synthase and spectroscopy, we previously demonstrated that the drug interacts with this protein near its unique tryptophan residue. Here, we show that replacement of ε's tryptophan with alanine resulted in bedaquiline hypersusceptibility of the bacteria. Overexpression of the wild-type ε subunit caused resistance. These results suggest that the drug also targets the ε subunit.
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