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Kaweewan I, Mukai K, Rukthanapitak P, Nakagawa H, Hosaka T, Kodani S. Heterologous biosynthesis of myxobacterial lanthipeptides melittapeptins. Appl Microbiol Biotechnol 2024; 108:122. [PMID: 38229328 DOI: 10.1007/s00253-023-12834-4] [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: 03/30/2023] [Revised: 09/28/2023] [Accepted: 10/30/2023] [Indexed: 01/18/2024]
Abstract
The myxobacteria are an attractive bioresource for bioactive compounds since the large size genome contains many biosynthetic gene clusters of secondary metabolites. The genome of the myxobacterium Melittangium boletus contains three biosynthetic gene clusters for lanthipeptide production. One of the gene clusters includes genes coding lanthipeptide precursor (melA), class II lanthipeptide synthetase (melM), and transporter (melT). The amino acid sequence of melA indicated similarity with that of known lanthipeptides mersacidin and lichenicidin A1 by the alignment. To perform heterologous production of new lanthipeptides, the expression vector containing the essential genes (melA and melM) was constructed by utilizing codon-optimized synthetic genes. The co-expression of two genes in the host bacterial cells of Escherichia coli BL21 (DE3) afforded new lanthipeptides named melittapeptins A-C. The structures of melittapeptins A-C including lanthionine/methyllanthionine bridge pattern were proposed based on protease digestion and MS/MS experiments. The native strain of M. boletus did not produce melittapeptins A-C, so heterologous production using the biosynthetic gene cluster was effective in obtaining the lanthipeptides. Melittapeptins A-C showed specific and potent antibacterial activity to the Gram-positive bacterium Micrococcus luteus. To the best of our knowledge, this is the first report of antibacterial lanthipeptides derived from myxobacterial origin. KEY POINTS: • New lanthipeptides melittapeptins were heterologously produced in Escherichia coli. • Melittapeptins showed specific antibacterial activity against Micrococcus luteus. • Melittapeptins were the first antibacterial lanthipeptides of myxobacterial origin.
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Affiliation(s)
- Issara Kaweewan
- Faculty of Agriculture, Shizuoka University, Shizuoka, Japan
- Faculty of Medicine, Chiang Mai University, Chiang Mai, Thailand
| | - Keiichiro Mukai
- Graduate School of Medicine, Science and Technology, Shinshu University, Nagano, Japan
- Department of Biomolecular Innovation, Institute for Biomedical Sciences, Shinshu University, Nagano, Japan
| | | | - Hiroyuki Nakagawa
- Research Center for Advanced Analysis, Core Technology Research Headquarters, National Agriculture and Food Research Organization (NARO), Ibaraki, Japan
| | - Takeshi Hosaka
- Graduate School of Medicine, Science and Technology, Shinshu University, Nagano, Japan
- Department of Biomolecular Innovation, Institute for Biomedical Sciences, Shinshu University, Nagano, Japan
| | - Shinya Kodani
- Faculty of Agriculture, Shizuoka University, Shizuoka, Japan.
- Graduate School of Integrated Science and Technology, Shizuoka University, Shizuoka, Japan.
- College of Agriculture, Academic Institute, Shizuoka University, 836 Ohya, Suruga-ku, Shizuoka, 422-8529, Japan.
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2
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Chauhan V, Baptista ISC, Arsh AM, Jagadeesan R, Dash S, Ribeiro AS. Transcription Attenuation in Synthetic Promoters in Nonoverlapping Tandem Formation. Biochemistry 2024; 63:2009-2022. [PMID: 38997112 PMCID: PMC11339919 DOI: 10.1021/acs.biochem.4c00012] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2024] [Revised: 07/01/2024] [Accepted: 07/01/2024] [Indexed: 07/14/2024]
Abstract
Closely spaced promoters are ubiquitous in prokaryotic and eukaryotic genomes. How their structure and dynamics relate remains unclear, particularly for tandem formations. To study their transcriptional interference, we engineered two pairs and one trio of synthetic promoters in nonoverlapping, tandem formation, in single-copy plasmids transformed into Escherichia coli cells. From in vivo measurements, we found that these promoters in tandem formation can have attenuated transcription rates. The attenuation strength can be widely fine-tuned by the promoters' positioning, natural regulatory mechanisms, and other factors, including the antibiotic rifampicin, which is known to hamper RNAP promoter escape. From this, and supported by in silico models, we concluded that the attenuation in these constructs emerges from premature terminations generated by collisions between RNAPs elongating from upstream promoters and RNAPs occupying downstream promoters. Moreover, we found that these collisions can cause one or both RNAPs to falloff. Finally, the broad spectrum of possible, externally regulated, attenuation strengths observed in our synthetic tandem promoters suggests that they could become useful as externally controllable regulators of future synthetic circuits.
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Affiliation(s)
- Vatsala Chauhan
- Faculty
of Medicine and Health Technology, Tampere
University, 33520 Tampere, Finland
- Department
of Cell and Molecular Biology (ICM), Uppsala
University, 751 24 Uppsala, Sweden
| | - Ines S. C. Baptista
- Faculty
of Medicine and Health Technology, Tampere
University, 33520 Tampere, Finland
| | - Amir M. Arsh
- Faculty
of Medicine and Health Technology, Tampere
University, 33520 Tampere, Finland
| | - Rahul Jagadeesan
- Faculty
of Medicine and Health Technology, Tampere
University, 33520 Tampere, Finland
| | - Suchintak Dash
- Faculty
of Medicine and Health Technology, Tampere
University, 33520 Tampere, Finland
| | - Andre S. Ribeiro
- Faculty
of Medicine and Health Technology, Tampere
University, 33520 Tampere, Finland
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3
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Li Q, Jansen H, Hansen G, Nurjadi D, Herrmann J, Stadler M, Brönstrup M, Müller R, He C, Graspeuntner S, Rupp J, Shima K. Inhibitory effect of sorangicin A against mutant DNA-dependent RNA polymerase in the obligate intracellular bacterium Chlamydia trachomatis. Int J Antimicrob Agents 2024; 63:107132. [PMID: 38432602 DOI: 10.1016/j.ijantimicag.2024.107132] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2023] [Revised: 01/19/2024] [Accepted: 02/26/2024] [Indexed: 03/05/2024]
Affiliation(s)
- Qiang Li
- Department of Infectious Diseases and Microbiology, University of Lübeck, Lübeck, Germany; College of Veterinary Medicine, China Agricultural University, Beijing, China
| | - Hendrik Jansen
- Department of Infectious Diseases and Microbiology, University of Lübeck, Lübeck, Germany; German Center for Infection Research, Partner Site Hamburg-Lübeck-Borstel-Riems, Lübeck, Germany
| | - Guido Hansen
- Institute of Biochemistry, Center for Structural and Cell Biology in Medicine, University of Lübeck, Lübeck, Germany
| | - Dennis Nurjadi
- Department of Infectious Diseases and Microbiology, University of Lübeck, Lübeck, Germany; German Center for Infection Research, Partner Site Hamburg-Lübeck-Borstel-Riems, Lübeck, Germany
| | - Jennifer Herrmann
- Helmholtz Centre for Infection Research, Helmholtz Institute for Pharmaceutical Research Saarland, and Department of Pharmacy, Saarland University, Saarbruecken, Germany; German Center for Infection Research, Partner Site Hannover-Braunschweig, Braunschweig, Germany
| | - Marc Stadler
- German Center for Infection Research, Partner Site Hannover-Braunschweig, Braunschweig, Germany; Department of Microbial Drugs, Helmholtz Centre for Infection Research, Braunschweig, Germany
| | - Mark Brönstrup
- German Center for Infection Research, Partner Site Hannover-Braunschweig, Braunschweig, Germany; Department of Chemical Biology, Helmholtz Centre for Infection Research, Braunschweig, Germany
| | - Rolf Müller
- Helmholtz Centre for Infection Research, Helmholtz Institute for Pharmaceutical Research Saarland, and Department of Pharmacy, Saarland University, Saarbruecken, Germany; German Center for Infection Research, Partner Site Hannover-Braunschweig, Braunschweig, Germany
| | - Cheng He
- College of Veterinary Medicine, China Agricultural University, Beijing, China
| | - Simon Graspeuntner
- Department of Infectious Diseases and Microbiology, University of Lübeck, Lübeck, Germany; German Center for Infection Research, Partner Site Hamburg-Lübeck-Borstel-Riems, Lübeck, Germany
| | - Jan Rupp
- Department of Infectious Diseases and Microbiology, University of Lübeck, Lübeck, Germany; German Center for Infection Research, Partner Site Hamburg-Lübeck-Borstel-Riems, Lübeck, Germany
| | - Kensuke Shima
- Department of Infectious Diseases and Microbiology, University of Lübeck, Lübeck, Germany.
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4
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Saggu SK, Nath A, Kumar S. Myxobacteria: biology and bioactive secondary metabolites. Res Microbiol 2023; 174:104079. [PMID: 37169232 DOI: 10.1016/j.resmic.2023.104079] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2023] [Revised: 04/22/2023] [Accepted: 05/04/2023] [Indexed: 05/13/2023]
Abstract
Myxobacteria are Gram-negative eubacteria and they thrive in a variety of habitats including soil rich in organic matter, rotting wood, animal dung and marine environment. Myxobacteria are a promising source of new compounds associated with diverse bioactive spectrum and unique mode of action. The genome information of myxobacteria has revealed many orphan biosynthetic pathways indicating that these bacteria can be the source of several novel natural products. In this review, we highlight the biology of myxobacteria with emphasis on their habitat, life cycle, isolation methods and enlist all the bioactive secondary metabolites purified till date and their mode of action.
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Affiliation(s)
- Sandeep Kaur Saggu
- Department of Biotechnology, Kanya Maha Vidyalaya, Jalandhar, Punjab, India - 144004.
| | - Amar Nath
- University Centre of Excellence in Research, Baba Farid University of Health Sciences, Faridkot, Punjab India 151203.
| | - Shiv Kumar
- Guru Gobind Singh Medical College, Baba Farid University of Health Sciences, Faridkot, Punjab India 151203.
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5
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Fries F, Kany AM, Rasheed S, Hirsch AKH, Müller R, Herrmann J. Impact of Drug Administration Routes on the In Vivo Efficacy of the Natural Product Sorangicin a Using a Staphylococcus aureus Infection Model in Zebrafish Embryos. Int J Mol Sci 2023; 24:12791. [PMID: 37628971 PMCID: PMC10454396 DOI: 10.3390/ijms241612791] [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: 06/28/2023] [Revised: 08/05/2023] [Accepted: 08/11/2023] [Indexed: 08/27/2023] Open
Abstract
Staphylococcus aureus causes a wide range of infections, and it is one of the leading pathogens responsible for deaths associated with antimicrobial resistance, the rapid spread of which among S. aureus urges the discovery of new antibiotics. The evaluation of in vivo efficacy of novel drug candidates is usually performed using animal models. Recently, zebrafish (Danio rerio) embryos have become increasingly attractive in early drug discovery. Herein, we established a zebrafish embryo model of S. aureus infection for evaluation of in vivo efficacy of novel potential antimicrobials. A local infection was induced by microinjecting mCherry-expressing S. aureus Newman followed by treatment with reference antibiotics via microinjection into different injection sites as well as via waterborne exposure to study the impact of the administration route on efficacy. We successfully used the developed model to evaluate the in vivo activity of the natural product sorangicin A, for which common mouse models were not successful due to fast degradation in plasma. In conclusion, we present a novel screening platform for assessing in vivo activity at the antibiotic discovery stage. Furthermore, this work provides consideration for the choice of an appropriate administration route based on the physicochemical properties of tested drugs.
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Affiliation(s)
- Franziska Fries
- Helmholtz Institute for Pharmaceutical Research Saarland (HIPS), Helmholtz Centre for Infection Research (HZI), Saarland University, Campus E8 1, 66123 Saarbrücken, Germany; (F.F.); (A.M.K.); (S.R.); (A.K.H.H.); (R.M.)
- German Centre for Infection Research (DZIF), Partner Site Hannover-Braunschweig, 38124 Braunschweig, Germany
- Department of Pharmacy, Saarland University, 66123 Saarbrücken, Germany
| | - Andreas M. Kany
- Helmholtz Institute for Pharmaceutical Research Saarland (HIPS), Helmholtz Centre for Infection Research (HZI), Saarland University, Campus E8 1, 66123 Saarbrücken, Germany; (F.F.); (A.M.K.); (S.R.); (A.K.H.H.); (R.M.)
| | - Sari Rasheed
- Helmholtz Institute for Pharmaceutical Research Saarland (HIPS), Helmholtz Centre for Infection Research (HZI), Saarland University, Campus E8 1, 66123 Saarbrücken, Germany; (F.F.); (A.M.K.); (S.R.); (A.K.H.H.); (R.M.)
- German Centre for Infection Research (DZIF), Partner Site Hannover-Braunschweig, 38124 Braunschweig, Germany
| | - Anna K. H. Hirsch
- Helmholtz Institute for Pharmaceutical Research Saarland (HIPS), Helmholtz Centre for Infection Research (HZI), Saarland University, Campus E8 1, 66123 Saarbrücken, Germany; (F.F.); (A.M.K.); (S.R.); (A.K.H.H.); (R.M.)
- German Centre for Infection Research (DZIF), Partner Site Hannover-Braunschweig, 38124 Braunschweig, Germany
- Department of Pharmacy, Saarland University, 66123 Saarbrücken, Germany
| | - Rolf Müller
- Helmholtz Institute for Pharmaceutical Research Saarland (HIPS), Helmholtz Centre for Infection Research (HZI), Saarland University, Campus E8 1, 66123 Saarbrücken, Germany; (F.F.); (A.M.K.); (S.R.); (A.K.H.H.); (R.M.)
- German Centre for Infection Research (DZIF), Partner Site Hannover-Braunschweig, 38124 Braunschweig, Germany
- Department of Pharmacy, Saarland University, 66123 Saarbrücken, Germany
| | - Jennifer Herrmann
- Helmholtz Institute for Pharmaceutical Research Saarland (HIPS), Helmholtz Centre for Infection Research (HZI), Saarland University, Campus E8 1, 66123 Saarbrücken, Germany; (F.F.); (A.M.K.); (S.R.); (A.K.H.H.); (R.M.)
- German Centre for Infection Research (DZIF), Partner Site Hannover-Braunschweig, 38124 Braunschweig, Germany
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6
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Peukert C, Vetter AC, Fuchs HLS, Harmrolfs K, Karge B, Stadler M, Brönstrup M. Siderophore conjugation with cleavable linkers boosts the potency of RNA polymerase inhibitors against multidrug-resistant E. coli. Chem Sci 2023; 14:5490-5502. [PMID: 37234900 PMCID: PMC10208051 DOI: 10.1039/d2sc06850h] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2022] [Accepted: 04/25/2023] [Indexed: 05/28/2023] Open
Abstract
The growing antibiotic resistance, foremost in Gram-negative bacteria, requires novel therapeutic approaches. We aimed to enhance the potency of well-established antibiotics targeting the RNA polymerase (RNAP) by utilizing the microbial iron transport machinery to improve drug translocation across their cell membrane. As covalent modifications resulted in moderate-low antibiotic activity, cleavable linkers were designed that permit a release of the antibiotic payload inside the bacteria and unperturbed target binding. A panel of ten cleavable siderophore-ciprofloxacin conjugates with systematic variation at the chelator and the linker moiety was used to identify the quinone trimethyl lock in conjugates 8 and 12 as the superior linker system, displaying minimal inhibitory concentrations (MICs) of ≤1 μM. Then, rifamycins, sorangicin A and corallopyronin A, representatives of three structurally and mechanistically different natural product RNAP inhibitor classes, were conjugated via the quinone linker to hexadentate hydroxamate and catecholate siderophores in 15-19 synthetic steps. MIC assays revealed an up to 32-fold increase in antibiotic activity against multidrug-resistant E. coli for conjugates such as 24 or 29 compared to free rifamycin. Experiments with knockout mutants in the transport system showed that translocation and antibiotic effects were conferred by several outer membrane receptors, whose coupling to the TonB protein was essential for activity. A functional release mechanism was demonstrated analytically by enzyme assays in vitro, and a combination of subcellular fractionation and quantitative mass spectrometry proved cellular uptake of the conjugate, release of the antibiotic, and its increased accumulation in the cytosol of bacteria. The study demonstrates how the potency of existing antibiotics against resistant Gram-negative pathogens can be boosted by adding functions for active transport and intracellular release.
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Affiliation(s)
- Carsten Peukert
- Department of Chemical Biology, Helmholtz Centre for Infection Research Inhoffenstraße 7 38124 Braunschweig Germany
| | - Anna C Vetter
- Department of Chemical Biology, Helmholtz Centre for Infection Research Inhoffenstraße 7 38124 Braunschweig Germany
| | - Hazel L S Fuchs
- Department of Chemical Biology, Helmholtz Centre for Infection Research Inhoffenstraße 7 38124 Braunschweig Germany
| | - Kirsten Harmrolfs
- Department of Chemical Biology, Helmholtz Centre for Infection Research Inhoffenstraße 7 38124 Braunschweig Germany
| | - Bianka Karge
- Department of Chemical Biology, Helmholtz Centre for Infection Research Inhoffenstraße 7 38124 Braunschweig Germany
| | - Marc Stadler
- Department of Microbial Drugs, Helmholtz Centre for Infection Research Inhoffenstraße 7 38124 Braunschweig Germany
- German Center for Infection Research (DZIF) Site Hannover-Braunschweig, Inhoffenstraße 7 38124 Braunschweig Germany
- Institute of Microbiology, Technische Universität Braunschweig Spielmannstraße 7 38106 Braunschweig Germany
| | - Mark Brönstrup
- Department of Chemical Biology, Helmholtz Centre for Infection Research Inhoffenstraße 7 38124 Braunschweig Germany
- German Center for Infection Research (DZIF) Site Hannover-Braunschweig, Inhoffenstraße 7 38124 Braunschweig Germany
- Institute for Organic Chemistry (IOC), Leibniz Universität Hannover Schneiderberg 1B 30167 Hannover Germany
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7
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Maingot M, Bourotte M, Vetter AC, Schellhorn B, Antraygues K, Scherer H, Gitzinger M, Kemmer C, Dale GE, Defert O, Lociuro S, Brönstrup M, Willand N, Trebosc V. Structure-activity relationships of actively FhuE transported rifabutin derivatives with potent activity against Acinetobacter baumannii. Eur J Med Chem 2023; 252:115257. [PMID: 36948128 DOI: 10.1016/j.ejmech.2023.115257] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2023] [Revised: 02/22/2023] [Accepted: 03/07/2023] [Indexed: 03/17/2023]
Abstract
Hospital-acquired infections are on the rise and represent both, a clinical and financial burden. With resistance emerging and an ever-dwindling armamentarium at hand, infections caused by Acinetobacter baumannii are particularly problematic, since these bacteria have a high level of resistance and resilience to traditional and even last-resort antibiotics. The antibiotic rifabutin was recently found to show potent in vitro and in vivo activity against extensively drug resistant A. baumannii. Building on this discovery, we report on the synthesis and activity of rifabutin analogs, with a focus on N-functionalization of the piperidine ring. The antimicrobial testing uncovered structure activity relationships (SAR) for A. baumannii that were not reflected in Staphylococcus aureus. The cellular activity did not correlate with cell-free transcription inhibition, but with bacterial intracellular compound accumulation. Mass spectrometry-based accumulation studies confirmed the involvement of the siderophore receptor FhuE in active compound translocation at low concentrations, and they showed a strong impact of the culture medium on the accumulation of rifabutin. Overall, the study underlines the structural feature required for strong accumulation of rifabutin in A. baumannii and identifies analogs as or more potent than rifabutin against A. baumannii.
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Affiliation(s)
- M Maingot
- Univ. Lille, Inserm, Institut Pasteur de Lille, U1177 - Drugs and Molecules for Living Systems, 59000, Lille, France
| | - M Bourotte
- BioVersys SAS, 1 rue du Professeur Calmette, 59000, Lille, France
| | - A C Vetter
- Department of Chemical Biology, Helmholtz Centre for Infection Research, Inhoffenstraße 7, 38124, Braunschweig, Germany
| | - B Schellhorn
- BioVersys AG, 60C Hochbergerstrasse, 4057, Basel, Switzerland
| | - K Antraygues
- Univ. Lille, Inserm, Institut Pasteur de Lille, U1177 - Drugs and Molecules for Living Systems, 59000, Lille, France
| | - H Scherer
- Univ. Lille, Inserm, Institut Pasteur de Lille, U1177 - Drugs and Molecules for Living Systems, 59000, Lille, France
| | - M Gitzinger
- BioVersys AG, 60C Hochbergerstrasse, 4057, Basel, Switzerland
| | - C Kemmer
- BioVersys AG, 60C Hochbergerstrasse, 4057, Basel, Switzerland
| | - G E Dale
- BioVersys AG, 60C Hochbergerstrasse, 4057, Basel, Switzerland
| | - O Defert
- BioVersys SAS, 1 rue du Professeur Calmette, 59000, Lille, France
| | - S Lociuro
- BioVersys AG, 60C Hochbergerstrasse, 4057, Basel, Switzerland
| | - M Brönstrup
- Department of Chemical Biology, Helmholtz Centre for Infection Research, Inhoffenstraße 7, 38124, Braunschweig, Germany
| | - N Willand
- Univ. Lille, Inserm, Institut Pasteur de Lille, U1177 - Drugs and Molecules for Living Systems, 59000, Lille, France.
| | - V Trebosc
- BioVersys AG, 60C Hochbergerstrasse, 4057, Basel, Switzerland.
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8
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Peukert C, Rox K, Karge B, Hotop SK, Brönstrup M. Synthesis and Characterization of DOTAM-Based Sideromycins for Bacterial Imaging and Antimicrobial Therapy. ACS Infect Dis 2023; 9:330-341. [PMID: 36719860 PMCID: PMC9927285 DOI: 10.1021/acsinfecdis.2c00523] [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: 10/17/2022] [Indexed: 02/01/2023]
Abstract
The rise of antimicrobial resistance, especially in Gram-negative bacteria, calls for novel diagnostics and antibiotics. To efficiently penetrate their double-layered cell membrane, we conjugated the potent antibiotics daptomycin, vancomycin, and sorangicin A to catechol siderophores, which are actively internalized by the bacterial iron uptake machinery. LC-MS/MS uptake measurements of sorangicin derivatives verified that the conjugation led to a 100- to 525-fold enhanced uptake into bacteria compared to the free drug. However, the transfer to the cytosol was insufficient, which explains their lack of antibiotic efficacy. Potent antimicrobial effects were observed for the daptomycin conjugate 7 (∼1 μM) against multidrug-resistant Acinetobacter baumannii. A cyanin-7 label aside the daptomycin warhead furnished the theranostic 13 that retained its antibiotic activity and was also able to label ESKAPE bacteria, as demonstrated by microscopy and fluorescence assays. 13 and the cyanin-7 imaging conjugate 14 were stable in human plasma and had low plasma protein binding and cytotoxicity.
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Affiliation(s)
- Carsten Peukert
- Department
of Chemical Biology, Helmholtz Centre for
Infection Research, Inhoffenstraße 7, 38124Braunschweig, Germany
| | - Katharina Rox
- Department
of Chemical Biology, Helmholtz Centre for
Infection Research, Inhoffenstraße 7, 38124Braunschweig, Germany
- German
Center for Infection Research (DZIF), Site Hannover-Braunschweig, Inhoffenstraße 7, 38124Braunschweig, Germany
| | - Bianka Karge
- Department
of Chemical Biology, Helmholtz Centre for
Infection Research, Inhoffenstraße 7, 38124Braunschweig, Germany
| | - Sven-Kevin Hotop
- Department
of Chemical Biology, Helmholtz Centre for
Infection Research, Inhoffenstraße 7, 38124Braunschweig, Germany
| | - Mark Brönstrup
- Department
of Chemical Biology, Helmholtz Centre for
Infection Research, Inhoffenstraße 7, 38124Braunschweig, Germany
- Institute
for Organic Chemistry (IOC), Leibniz Universität
Hannover, Schneiderberg
1B, 30167Hannover, Germany
- German
Center for Infection Research (DZIF), Site Hannover-Braunschweig, Inhoffenstraße 7, 38124Braunschweig, Germany
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9
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Sullivan JR, Yao J, Courtine C, Lupien A, Herrmann J, Müller R, Behr MA. Natural Products Lysobactin and Sorangicin A Show In Vitro Activity against Mycobacterium abscessus Complex. Microbiol Spectr 2022; 10:e0267222. [PMID: 36342177 PMCID: PMC9769517 DOI: 10.1128/spectrum.02672-22] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2022] [Accepted: 10/08/2022] [Indexed: 11/09/2022] Open
Abstract
The prevalence of lung disease caused by Mycobacterium abscessus is increasing among patients with cystic fibrosis. M. abscessus is a multidrug resistant opportunistic pathogen that is notoriously difficult to treat due to a lack of efficacious therapeutic regimens. Currently, there are no standard regimens, and treatment guidelines are based empirically on drug susceptibility testing. Thus, novel antibiotics are required. Natural products represent a vast pool of biologically active compounds that have a history of being a good source of antibiotics. Here, we screened a library of 517 natural products purified from fermentations of various bacteria, fungi, and plants against M. abscessus ATCC 19977. Lysobactin and sorangicin A were active against the M. abscessus complex and drug resistant clinical isolates. These natural products merit further consideration to be included in the M. abscessus drug pipeline. IMPORTANCE The many thousands of people living with cystic fibrosis are at a greater risk of developing a chronic lung infection caused by Mycobacterium abscessus. Since M. abscessus is clinically resistant to most anti-TB drugs available, treatment options are limited to macrolides. Despite macrolide-based therapies, cure rates for M. abscessus lung infections are 50%. Using an in-house library of curated natural products, we identified lysobactin and sorangicin A as novel scaffolds for the future development of antimicrobials for patients with M. abscessus infections.
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Affiliation(s)
- Jaryd R. Sullivan
- Department of Microbiology & Immunology, McGill University, Montréal, Québec, Canada
- Infectious Diseases and Immunity in Global Health Program, Research Institute of the McGill University Health Centre, Montréal, Québec, Canada
- McGill International TB Centre, Montréal, Québec, Canada
| | - Jacqueline Yao
- Infectious Diseases and Immunity in Global Health Program, Research Institute of the McGill University Health Centre, Montréal, Québec, Canada
| | - Christophe Courtine
- Department of Microbiology & Immunology, McGill University, Montréal, Québec, Canada
- Infectious Diseases and Immunity in Global Health Program, Research Institute of the McGill University Health Centre, Montréal, Québec, Canada
| | - Andréanne Lupien
- Infectious Diseases and Immunity in Global Health Program, Research Institute of the McGill University Health Centre, Montréal, Québec, Canada
- McGill International TB Centre, Montréal, Québec, Canada
| | - Jennifer Herrmann
- Department of Microbial Natural Products, Helmholtz-Institute for Pharmaceutical Research Saarland (HIPS), Helmholtz Centre for Infection Research (HZI),Saarbrücken, Germany
| | - Rolf Müller
- Department of Microbial Natural Products, Helmholtz-Institute for Pharmaceutical Research Saarland (HIPS), Helmholtz Centre for Infection Research (HZI),Saarbrücken, Germany
- Department of Pharmacy, Saarland University, Saarbrücken, Germany
| | - Marcel A. Behr
- Department of Microbiology & Immunology, McGill University, Montréal, Québec, Canada
- Infectious Diseases and Immunity in Global Health Program, Research Institute of the McGill University Health Centre, Montréal, Québec, Canada
- McGill International TB Centre, Montréal, Québec, Canada
- Department of Medicine, McGill University Health Centre, Montréal, Québec, Canada
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10
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Stephanie F, Tambunan USF, Siahaan TJ. M. tuberculosis Transcription Machinery: A Review on the Mycobacterial RNA Polymerase and Drug Discovery Efforts. Life (Basel) 2022; 12:1774. [PMID: 36362929 PMCID: PMC9695777 DOI: 10.3390/life12111774] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2022] [Revised: 10/24/2022] [Accepted: 11/01/2022] [Indexed: 09/08/2023] Open
Abstract
Mycobacterium tuberculosis (MTB) is the main source of tuberculosis (TB), one of the oldest known diseases in the human population. Despite the drug discovery efforts of past decades, TB is still one of the leading causes of mortality and claimed more than 1.5 million lives worldwide in 2020. Due to the emergence of drug-resistant strains and patient non-compliance during treatments, there is a pressing need to find alternative therapeutic agents for TB. One of the important areas for developing new treatments is in the inhibition of the transcription step of gene expression; it is the first step to synthesize a copy of the genetic material in the form of mRNA. This further translates to functional protein synthesis, which is crucial for the bacteria living processes. MTB contains a bacterial DNA-dependent RNA polymerase (RNAP), which is the key enzyme for the transcription process. MTB RNAP has been targeted for designing and developing antitubercular agents because gene transcription is essential for the mycobacteria survival. Initiation, elongation, and termination are the three important sequential steps in the transcription process. Each step is complex and highly regulated, involving multiple transcription factors. This review is focused on the MTB transcription machinery, especially in the nature of MTB RNAP as the main enzyme that is regulated by transcription factors. The mechanism and conformational dynamics that occur during transcription are discussed and summarized. Finally, the current progress on MTB transcription inhibition and possible drug target in mycobacterial RNAP are also described to provide insight for future antitubercular drug design and development.
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Affiliation(s)
- Filia Stephanie
- Department of Chemistry, Faculty of Mathematics and Natural Sciences, Universitas Indonesia, Depok 16424, Indonesia
| | - Usman Sumo Friend Tambunan
- Department of Chemistry, Faculty of Mathematics and Natural Sciences, Universitas Indonesia, Depok 16424, Indonesia
| | - Teruna J. Siahaan
- Department of Pharmaceutical Chemistry, School of Pharmacy, The University of Kansas, Lawrence, KS 66045, USA
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11
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Caputo A, Sartini S, Levati E, Minato I, Elisi GM, Di Stasi A, Guillou C, Goekjian PG, Garcia P, Gueyrard D, Bach S, Comte A, Ottonello S, Rivara S, Montanini B. An Optimized Workflow for the Discovery of New Antimicrobial Compounds Targeting Bacterial RNA Polymerase Complex Formation. Antibiotics (Basel) 2022; 11:antibiotics11101449. [PMID: 36290107 PMCID: PMC9598883 DOI: 10.3390/antibiotics11101449] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2022] [Revised: 10/14/2022] [Accepted: 10/17/2022] [Indexed: 11/16/2022] Open
Abstract
Bacterial resistance represents a major health problem worldwide and there is an urgent need to develop first-in-class compounds directed against new therapeutic targets. We previously developed a drug-discovery platform to identify new antimicrobials able to disrupt the protein–protein interaction between the β’ subunit and the σ70 initiation factor of bacterial RNA polymerase, which is essential for transcription. As a follow-up to such work, we have improved the discovery strategy to make it less time-consuming and more cost-effective. This involves three sequential assays, easily scalable to a high-throughput format, and a subsequent in-depth characterization only limited to hits that passed the three tests. This optimized workflow, applied to the screening of 5360 small molecules from three synthetic and natural compound libraries, led to the identification of six compounds interfering with the β’–σ70 interaction, and thus was capable of inhibiting promoter-specific RNA transcription and bacterial growth. Upon supplementation with a permeability adjuvant, the two most potent transcription-inhibiting compounds displayed a strong antibacterial activity against Escherichia coli with minimum inhibitory concentration (MIC) values among the lowest (0.87–1.56 μM) thus far reported for β’–σ PPI inhibitors. The newly identified hit compounds share structural feature similarities with those of a pharmacophore model previously developed from known inhibitors.
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Affiliation(s)
- Alessia Caputo
- Laboratory of Biochemistry and Molecular Biology, Department of Chemistry, Life Sciences and Environmental Sustainability, University of Parma, 43124 Parma, Italy
- Interdepartmental Research Centre Biopharmanet-Tec, University of Parma, 43124 Parma, Italy
| | - Sara Sartini
- Laboratory of Biochemistry and Molecular Biology, Department of Chemistry, Life Sciences and Environmental Sustainability, University of Parma, 43124 Parma, Italy
- Department of Orthopaedic Surgery, David Geffen School of Medicine, University of California Los Angeles (UCLA), Los Angeles, CA 90095, USA
| | - Elisabetta Levati
- Laboratory of Biochemistry and Molecular Biology, Department of Chemistry, Life Sciences and Environmental Sustainability, University of Parma, 43124 Parma, Italy
| | - Ilaria Minato
- Laboratory of Biochemistry and Molecular Biology, Department of Chemistry, Life Sciences and Environmental Sustainability, University of Parma, 43124 Parma, Italy
- Interdepartmental Research Centre Biopharmanet-Tec, University of Parma, 43124 Parma, Italy
| | - Gian Marco Elisi
- Department of Food and Drug, University of Parma, 43124 Parma, Italy
| | - Adriana Di Stasi
- Department of Life Sciences, University of Trieste, 34127 Trieste, Italy
| | - Catherine Guillou
- Centre de Recherche de Gif, Institut de Chimie des Substances Naturelles, CNRS, 1 Avenue de la Terrasse, 91198 Gif-sur-Yvette, France
| | - Peter G. Goekjian
- Laboratoire Chimie Organique 2 Glycochimie, ICBMS UMR 5246 CNRS-Université Claude Bernard Lyon 1, Université de Lyon, 69622 Villeurbanne, France
| | - Pierre Garcia
- Laboratoire Chimie Organique 2 Glycochimie, ICBMS UMR 5246 CNRS-Université Claude Bernard Lyon 1, Université de Lyon, 69622 Villeurbanne, France
| | - David Gueyrard
- Laboratoire Chimie Organique 2 Glycochimie, ICBMS UMR 5246 CNRS-Université Claude Bernard Lyon 1, Université de Lyon, 69622 Villeurbanne, France
| | - Stéphane Bach
- Sorbonne Université, CNRS, UMR 8227, Integrative Biology of Marine Models, Team Physiology and Cell Fate, Station Biologique de Roscoff, CS 90074, 29680 Roscoff, France
- Sorbonne Université, CNRS, FR 2424, Plateforme de criblage KISSf (Kinase Inhibitor Specialized Screening Facility), Station Biologique de Roscoff, 29680 Roscoff, France
- Centre of Excellence for Pharmaceutical Sciences, North-West University, Private Bag X6001, Potchefstroom 2520, South Africa
| | - Arnaud Comte
- Chimiothèque, ICBMS UMR 5246 CNRS-Université Claude Bernard Lyon 1, Université de Lyon, 69622 Villeurbanne, France
| | - Simone Ottonello
- Laboratory of Biochemistry and Molecular Biology, Department of Chemistry, Life Sciences and Environmental Sustainability, University of Parma, 43124 Parma, Italy
- Interdepartmental Research Centre Biopharmanet-Tec, University of Parma, 43124 Parma, Italy
| | - Silvia Rivara
- Interdepartmental Research Centre Biopharmanet-Tec, University of Parma, 43124 Parma, Italy
- Department of Food and Drug, University of Parma, 43124 Parma, Italy
| | - Barbara Montanini
- Laboratory of Biochemistry and Molecular Biology, Department of Chemistry, Life Sciences and Environmental Sustainability, University of Parma, 43124 Parma, Italy
- Interdepartmental Research Centre Biopharmanet-Tec, University of Parma, 43124 Parma, Italy
- Correspondence: ; Tel.: +39-0521-905654
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12
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Kirsch SH, Haeckl FPJ, Müller R. Beyond the approved: target sites and inhibitors of bacterial RNA polymerase from bacteria and fungi. Nat Prod Rep 2022; 39:1226-1263. [PMID: 35507039 DOI: 10.1039/d1np00067e] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Covering: 2016 to 2022RNA polymerase (RNAP) is the central enzyme in bacterial gene expression representing an attractive and validated target for antibiotics. Two well-known and clinically approved classes of natural product RNAP inhibitors are the rifamycins and the fidaxomycins. Rifampicin (Rif), a semi-synthetic derivative of rifamycin, plays a crucial role as a first line antibiotic in the treatment of tuberculosis and a broad range of bacterial infections. However, more and more pathogens such as Mycobacterium tuberculosis develop resistance, not only against Rif and other RNAP inhibitors. To overcome this problem, novel RNAP inhibitors exhibiting different target sites are urgently needed. This review includes recent developments published between 2016 and today. Particular focus is placed on novel findings concerning already known bacterial RNAP inhibitors, the characterization and development of new compounds isolated from bacteria and fungi, and providing brief insights into promising new synthetic compounds.
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Affiliation(s)
- Susanne H Kirsch
- Helmholtz Institute for Pharmaceutical Research Saarland (HIPS), Helmholtz Centre for Infection Research (HZI), Saarland University Campus, 66123 Saarbrücken, Germany. .,German Centre for Infection Research (DZIF), Partner Site Hannover-Braunschweig, 38124 Braunschweig, Germany
| | - F P Jake Haeckl
- Helmholtz Institute for Pharmaceutical Research Saarland (HIPS), Helmholtz Centre for Infection Research (HZI), Saarland University Campus, 66123 Saarbrücken, Germany. .,German Centre for Infection Research (DZIF), Partner Site Hannover-Braunschweig, 38124 Braunschweig, Germany
| | - Rolf Müller
- Helmholtz Institute for Pharmaceutical Research Saarland (HIPS), Helmholtz Centre for Infection Research (HZI), Saarland University Campus, 66123 Saarbrücken, Germany. .,German Centre for Infection Research (DZIF), Partner Site Hannover-Braunschweig, 38124 Braunschweig, Germany.,Department of Pharmacy, Saarland University, 66123 Saarbrücken, Germany
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13
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Skrzypczak N, Przybylski P. Modifications, biological origin and antibacterial activity of naphthalenoid ansamycins. Nat Prod Rep 2022; 39:1653-1677. [PMID: 35244668 DOI: 10.1039/d2np00002d] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Covering: 2011 to 2021Structural division of natural naphthalenoid ansamycins, regarding the type of the core and length of the ansa chain, and their biosynthetic pathways in microorganisms are discussed. The great biosynthetic plasticity of natural naphthalenoid ansamycins is reflected in their structural variety due to the alterations within ansa bridge or naphthalenoid core portions. A comparison between the biological potency of natural and semisynthetic naphthalenoid ansamycins was performed and discussed in relation to the molecular targets in cells. The antibacterial potency of naphthalenoid ansamycins seems to be dependent on the ansa chain length and conformational flexibility - the higher flexibility of the ansa chain the better biological outcome is noted.
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Affiliation(s)
- Natalia Skrzypczak
- Faculty of Chemistry, Adam Mickiewicz University, Uniwersytetu Poznanskiego 8, 61-614 Poznan, Poland.
| | - Piotr Przybylski
- Faculty of Chemistry, Adam Mickiewicz University, Uniwersytetu Poznanskiego 8, 61-614 Poznan, Poland.
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14
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Bhat MA, Mishra AK, Bhat MA, Banday MI, Bashir O, Rather IA, Rahman S, Shah AA, Jan AT. Myxobacteria as a Source of New Bioactive Compounds: A Perspective Study. Pharmaceutics 2021; 13:1265. [PMID: 34452226 PMCID: PMC8401837 DOI: 10.3390/pharmaceutics13081265] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2021] [Revised: 08/06/2021] [Accepted: 08/09/2021] [Indexed: 12/18/2022] Open
Abstract
Myxobacteria are unicellular, Gram-negative, soil-dwelling, gliding bacteria that belong to class δ-proteobacteria and order Myxococcales. They grow and proliferate by transverse fission under normal conditions, but form fruiting bodies which contain myxospores during unfavorable conditions. In view of the escalating problem of antibiotic resistance among disease-causing pathogens, it becomes mandatory to search for new antibiotics effective against such pathogens from natural sources. Among the different approaches, Myxobacteria, having a rich armor of secondary metabolites, preferably derivatives of polyketide synthases (PKSs) along with non-ribosomal peptide synthases (NRPSs) and their hybrids, are currently being explored as producers of new antibiotics. The Myxobacterial species are functionally characterized to assess their ability to produce antibacterial, antifungal, anticancer, antimalarial, immunosuppressive, cytotoxic and antioxidative bioactive compounds. In our study, we have found their compounds to be effective against a wide range of pathogens associated with the concurrence of different infectious diseases.
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Affiliation(s)
- Mudasir Ahmad Bhat
- Department of Biotechnology, Baba Ghulam Shah Badshah University, Rajouri 185234, Jammu and Kashmir, India;
| | | | - Mujtaba Aamir Bhat
- Department of Botany, Baba Ghulam Shah Badshah University, Rajouri 185234, Jammu and Kashmir, India;
| | - Mohammad Iqbal Banday
- Department of Microbiology, Baba Ghulam Shah Badshah University, Rajouri 185234, Jammu and Kashmir, India;
| | - Ommer Bashir
- Department of School Education, Jammu 181205, Jammu and Kashmir, India;
| | - Irfan A. Rather
- Department of Biological Sciences, Faculty of Science, King Abdulaziz University (KAU), Jeddah 21589, Saudi Arabia;
| | - Safikur Rahman
- Department of Botany, MS College, BR Ambedkar Bihar University, Muzaffarpur 845401, Bihar, India;
| | - Ali Asghar Shah
- Department of Biotechnology, Baba Ghulam Shah Badshah University, Rajouri 185234, Jammu and Kashmir, India;
| | - Arif Tasleem Jan
- Department of Botany, Baba Ghulam Shah Badshah University, Rajouri 185234, Jammu and Kashmir, India;
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15
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The antibiotic sorangicin A inhibits promoter DNA unwinding in a Mycobacterium tuberculosis rifampicin-resistant RNA polymerase. Proc Natl Acad Sci U S A 2020; 117:30423-30432. [PMID: 33199626 PMCID: PMC7720108 DOI: 10.1073/pnas.2013706117] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023] Open
Abstract
Rifampicin (Rif) is a first-line therapeutic used to treat the infectious disease tuberculosis (TB), which is caused by the pathogen Mycobacterium tuberculosis (Mtb). The emergence of Rif-resistant (RifR) Mtb presents a need for new antibiotics. Rif targets the enzyme RNA polymerase (RNAP). Sorangicin A (Sor) is an unrelated inhibitor that binds in the Rif-binding pocket of RNAP. Sor inhibits a subset of RifR RNAPs, including the most prevalent clinical RifR RNAP substitution found in Mtb infected patients (S456>L of the β subunit). Here, we present structural and biochemical data demonstrating that Sor inhibits the wild-type Mtb RNAP by a similar mechanism as Rif: by preventing the translocation of very short RNAs. By contrast, Sor inhibits the RifR S456L enzyme at an earlier step, preventing the transition of a partially unwound promoter DNA intermediate to the fully opened DNA and blocking the template-strand DNA from reaching the active site in the RNAP catalytic center. By defining template-strand blocking as a mechanism for inhibition, we provide a mechanistic drug target in RNAP. Our finding that Sor inhibits the wild-type and mutant RNAPs through different mechanisms prompts future considerations for designing antibiotics against resistant targets. Also, we show that Sor has a better pharmacokinetic profile than Rif, making it a suitable starting molecule to design drugs to be used for the treatment of TB patients with comorbidities who require multiple medications.
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16
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Diverse and unified mechanisms of transcription initiation in bacteria. Nat Rev Microbiol 2020; 19:95-109. [PMID: 33122819 DOI: 10.1038/s41579-020-00450-2] [Citation(s) in RCA: 65] [Impact Index Per Article: 16.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/07/2020] [Indexed: 12/21/2022]
Abstract
Transcription of DNA is a fundamental process in all cellular organisms. The enzyme responsible for transcription, RNA polymerase, is conserved in general architecture and catalytic function across the three domains of life. Diverse mechanisms are used among and within the different branches to regulate transcription initiation. Mechanistic studies of transcription initiation in bacteria are especially amenable because the promoter recognition and melting steps are much less complicated than in eukaryotes or archaea. Also, bacteria have critical roles in human health as pathogens and commensals, and the bacterial RNA polymerase is a proven target for antibiotics. Recent biophysical studies of RNA polymerases and their inhibition, as well as transcription initiation and transcription factors, have detailed the mechanisms of transcription initiation in phylogenetically diverse bacteria, inspiring this Review to examine unifying and diverse themes in this process.
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17
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Elkarhat Z, Charoute H, Elkhattabi L, Barakat A, Rouba H. Potential inhibitors of SARS-cov-2 RNA dependent RNA polymerase protein: molecular docking, molecular dynamics simulations and MM-PBSA analyses. J Biomol Struct Dyn 2020; 40:361-374. [PMID: 32873176 DOI: 10.1080/07391102.2020.1813628] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
The SARS-cov-2 RNA dependent RNA polymerase (nsp12) is a crucial viral enzyme that catalyzes the replication of RNA from RNA templates. The fixation of some ligands in the active site may alter the viral life cycle. The aim of the present study is to identify the conservation level of nsp12 motifs (A-G), using consurf server, and discover their interactions with rifabutin, rifampicin, rifapentin, sorangicin A, streptolydigin, myxopyronin B, VXR and VRX using AutoDockTools-1.5.6, Gromacs 2018.2 and g-mmpbsa. Thus, the most of amino acids residues located in nsp12 protein Motifs (A-G) were predicted as highly conserved. The binding energies of streptolydigin, VXR, rifabutin, rifapentine, VRX, sorangicin A, myxopyronin B and rifampicin with nsp12 protein are -8.11, -8.23, -7.14, -6.94, -6.55, -5.46, -5.33 and -5.26 kcal/mol, respectively. In the other hand, the binding energies of ligand in the same order with nsp7-nsp8-nsp12 complex are -7.23, -7.08, -7.21, -7, -6.59, -8.73, -5.52, -5.87 kcal/mol, respectively. All ligands interact with at least two nsp12 motifs. The molecular dynamics simulation of nsp12-streptolydigin and nsp12-VXR complexes shows that these two complexes are stable and the number of hydrogen bonds as a function of time, after 30 ns of simulation, varies between 0 and 6 for nsp12-streptolydigin complex and between 0 and 4 for nsp12-VXR complex. The average of free binding energies obtained using g_mmpbsa, after 30 ns of simulation, is -191.982 Kj/mol for nsp12-streptolydigin complex and -153.583 Kj/mol for nsp12-VXR complex. Our results suggest that these ligands may be used as inhibitors of SARS-cov-2 nsp12 protein.Communicated by Ramaswamy H. Sarma.
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Affiliation(s)
- Zouhair Elkarhat
- Laboratory of Genomics and Human Genetics, Département de la Recherche Scientifique, Institut Pasteur du Maroc, Casablanca, Morocco
| | - Hicham Charoute
- Laboratory of Genomics and Human Genetics, Département de la Recherche Scientifique, Institut Pasteur du Maroc, Casablanca, Morocco
| | - Lamiae Elkhattabi
- Laboratory of Genomics and Human Genetics, Département de la Recherche Scientifique, Institut Pasteur du Maroc, Casablanca, Morocco
| | - Abdelhamid Barakat
- Laboratory of Genomics and Human Genetics, Département de la Recherche Scientifique, Institut Pasteur du Maroc, Casablanca, Morocco
| | - Hassan Rouba
- Laboratory of Genomics and Human Genetics, Département de la Recherche Scientifique, Institut Pasteur du Maroc, Casablanca, Morocco
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18
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Pokhrel R, Chapagain P, Siltberg-Liberles J. Potential RNA-dependent RNA polymerase inhibitors as prospective therapeutics against SARS-CoV-2. J Med Microbiol 2020; 69:864-873. [PMID: 32469301 PMCID: PMC7451031 DOI: 10.1099/jmm.0.001203] [Citation(s) in RCA: 39] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2020] [Accepted: 04/27/2020] [Indexed: 01/13/2023] Open
Abstract
Introduction. The emergence of SARS-CoV-2 has taken humanity off guard. Following an outbreak of SARS-CoV in 2002, and MERS-CoV about 10 years later, SARS-CoV-2 is the third coronavirus in less than 20 years to cross the species barrier and start spreading by human-to-human transmission. It is the most infectious of the three, currently causing the COVID-19 pandemic. No treatment has been approved for COVID-19. We previously proposed targets that can serve as binding sites for antiviral drugs for multiple coronaviruses, and here we set out to find current drugs that can be repurposed as COVID-19 therapeutics.Aim. To identify drugs against COVID-19, we performed an in silico virtual screen with the US Food and Drug Administration (FDA)-approved drugs targeting the RNA-dependent RNA polymerase (RdRP), a critical enzyme for coronavirus replication.Methodology. Initially, no RdRP structure of SARS-CoV-2 was available. We performed basic sequence and structural analysis to determine if RdRP from SARS-CoV was a suitable replacement. We performed molecular dynamics simulations to generate multiple starting conformations that were used for the in silico virtual screen. During this work, a structure of RdRP from SARS-CoV-2 became available and was also included in the in silico virtual screen.Results. The virtual screen identified several drugs predicted to bind in the conserved RNA tunnel of RdRP, where many of the proposed targets were located. Among these candidates, quinupristin is particularly interesting because it is expected to bind across the RNA tunnel, blocking access from both sides and suggesting that it has the potential to arrest viral replication by preventing viral RNA synthesis. Quinupristin is an antibiotic that has been in clinical use for two decades and is known to cause relatively minor side effects.Conclusion. Quinupristin represents a potential anti-SARS-CoV-2 therapeutic. At present, we have no evidence that this drug is effective against SARS-CoV-2 but expect that the biomedical community will expeditiously follow up on our in silico findings.
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Affiliation(s)
- Rudramani Pokhrel
- Department of Physics, Florida International University, 11200 SW 8th St, Miami, FL 33199, USA
| | - Prem Chapagain
- Department of Physics, Florida International University, 11200 SW 8th St, Miami, FL 33199, USA
- Biomolecular Sciences Institute, Florida International University, 11200 SW 8th St, Miami, FL 33199, USA
| | - Jessica Siltberg-Liberles
- Biomolecular Sciences Institute, Florida International University, 11200 SW 8th St, Miami, FL 33199, USA
- Department of Biological Sciences, Florida International University, 11200 SW 8th St, Miami, FL 33199, USA
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19
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Danelius E, Poongavanam V, Peintner S, Wieske LHE, Erdélyi M, Kihlberg J. Solution Conformations Explain the Chameleonic Behaviour of Macrocyclic Drugs. Chemistry 2020; 26:5231-5244. [DOI: 10.1002/chem.201905599] [Citation(s) in RCA: 40] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2019] [Indexed: 02/02/2023]
Affiliation(s)
- Emma Danelius
- Department of Chemistry-BMCUppsala University 75123 Uppsala Sweden
| | | | - Stefan Peintner
- Department of Chemistry-BMCUppsala University 75123 Uppsala Sweden
| | | | - Máté Erdélyi
- Department of Chemistry-BMCUppsala University 75123 Uppsala Sweden
| | - Jan Kihlberg
- Department of Chemistry-BMCUppsala University 75123 Uppsala Sweden
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20
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Olatunji S, Yu X, Bailey J, Huang CY, Zapotoczna M, Bowen K, Remškar M, Müller R, Scanlan EM, Geoghegan JA, Olieric V, Caffrey M. Structures of lipoprotein signal peptidase II from Staphylococcus aureus complexed with antibiotics globomycin and myxovirescin. Nat Commun 2020; 11:140. [PMID: 31919415 PMCID: PMC6952399 DOI: 10.1038/s41467-019-13724-y] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2019] [Accepted: 11/20/2019] [Indexed: 01/22/2023] Open
Abstract
Antimicrobial resistance is a major global threat that calls for new antibiotics. Globomycin and myxovirescin are two natural antibiotics that target the lipoprotein-processing enzyme, LspA, thereby compromising the integrity of the bacterial cell envelope. As part of a project aimed at understanding their mechanism of action and for drug development, we provide high-resolution crystal structures of the enzyme from the human pathogen methicillin-resistant Staphylococcus aureus (MRSA) complexed with globomycin and with myxovirescin. Our results reveal an instance of convergent evolution. The two antibiotics possess different molecular structures. Yet, they appear to inhibit identically as non-cleavable tetrahedral intermediate analogs. Remarkably, the two antibiotics superpose along nineteen contiguous atoms that interact similarly with LspA. This 19-atom motif recapitulates a part of the substrate lipoprotein in its proposed binding mode. Incorporating this motif into a scaffold with suitable pharmacokinetic properties should enable the development of effective antibiotics with built-in resistance hardiness. The enzyme LspA from the human pathogen Staphylococcus aureus (MRSA) contributes to the integrity and function of the bacterial cell envelope. Here, authors provide crystal structures of LspA in complex with two natural antibiotics, which have profoundly different structures but inhibit LspA in an identical way.
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Affiliation(s)
- Samir Olatunji
- Membrane Structural and Functional Biology Group, School of Medicine and School of Biochemistry and Immunology, Trinity College Dublin, Dublin, D02 R590, Ireland
| | - Xiaoxiao Yu
- Membrane Structural and Functional Biology Group, School of Medicine and School of Biochemistry and Immunology, Trinity College Dublin, Dublin, D02 R590, Ireland
| | - Jonathan Bailey
- Membrane Structural and Functional Biology Group, School of Medicine and School of Biochemistry and Immunology, Trinity College Dublin, Dublin, D02 R590, Ireland
| | - Chia-Ying Huang
- Swiss Light Source, Paul Scherrer Institute, CH-5232, Villigen, Switzerland
| | - Marta Zapotoczna
- Moyne Institute of Preventive Medicine, Department of Microbiology, School of Genetics and Microbiology, Trinity College Dublin, Dublin, D02, Ireland
| | - Katherine Bowen
- School of Chemistry, Trinity College Dublin, Dublin, D02 R590, Ireland
| | - Maja Remškar
- Department Microbial Natural Products, Helmholtz-Institute for Pharmaceutical Research Saarland, Helmholtz Centre for Infection Research and Department of Pharmacy, Saarland University Campus E8 1, D-66123, Saarbrücken, Germany
| | - Rolf Müller
- Department Microbial Natural Products, Helmholtz-Institute for Pharmaceutical Research Saarland, Helmholtz Centre for Infection Research and Department of Pharmacy, Saarland University Campus E8 1, D-66123, Saarbrücken, Germany
| | - Eoin M Scanlan
- School of Chemistry, Trinity College Dublin, Dublin, D02 R590, Ireland
| | - Joan A Geoghegan
- Moyne Institute of Preventive Medicine, Department of Microbiology, School of Genetics and Microbiology, Trinity College Dublin, Dublin, D02, Ireland
| | - Vincent Olieric
- Swiss Light Source, Paul Scherrer Institute, CH-5232, Villigen, Switzerland
| | - Martin Caffrey
- Membrane Structural and Functional Biology Group, School of Medicine and School of Biochemistry and Immunology, Trinity College Dublin, Dublin, D02 R590, Ireland.
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21
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Yelin I, Flett KB, Merakou C, Mehrotra P, Stam J, Snesrud E, Hinkle M, Lesho E, McGann P, McAdam AJ, Sandora TJ, Kishony R, Priebe GP. Genomic and epidemiological evidence of bacterial transmission from probiotic capsule to blood in ICU patients. Nat Med 2019; 25:1728-1732. [PMID: 31700189 PMCID: PMC6980696 DOI: 10.1038/s41591-019-0626-9] [Citation(s) in RCA: 154] [Impact Index Per Article: 30.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2018] [Accepted: 09/25/2019] [Indexed: 11/09/2022]
Abstract
Probiotics are routinely administered to hospitalized patients for many potential indications1 but have been associated with adverse effects that may outweigh their potential benefits2-7. It is particularly alarming that probiotic strains can cause bacteremia8,9, yet direct evidence for an ancestral link between blood isolates and administered probiotics is lacking. Here we report a markedly higher risk of Lactobacillus bacteremia for intensive care unit (ICU) patients treated with probiotics compared to those not treated, and provide genomics data that support the idea of direct clonal transmission of probiotics to the bloodstream. Whole-genome-based phylogeny showed that Lactobacilli isolated from treated patients' blood were phylogenetically inseparable from Lactobacilli isolated from the associated probiotic product. Indeed, the minute genetic diversity among the blood isolates mostly mirrored pre-existing genetic heterogeneity found in the probiotic product. Some blood isolates also contained de novo mutations, including a non-synonymous SNP conferring antibiotic resistance in one patient. Our findings support that probiotic strains can directly cause bacteremia and adaptively evolve within ICU patients.
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Affiliation(s)
- Idan Yelin
- Department of Biology, Technion-Israel Institute of Technology, Haifa, Israel
| | - Kelly B Flett
- Division of Infectious Diseases, Department of Pediatrics, Boston Children's Hospital, Boston, MA, USA
- Harvard Medical School, Boston, MA, USA
- Novant Health Eastover Pediatrics, Charlotte, NC, USA
| | - Christina Merakou
- Harvard Medical School, Boston, MA, USA
- Division of Critical Care Medicine, Department of Anesthesiology, Critical Care and Pain Medicine, Boston Children's Hospital, Boston, MA, USA
| | - Preeti Mehrotra
- Division of Infectious Diseases, Department of Pediatrics, Boston Children's Hospital, Boston, MA, USA
- Division of Infectious Diseases, Beth Israel Deaconess Medical Center, Boston, MA, USA
| | - Jason Stam
- Walter Reed Army Institute of Research, Silver Spring, MD, USA
| | - Erik Snesrud
- Walter Reed Army Institute of Research, Silver Spring, MD, USA
| | - Mary Hinkle
- Walter Reed Army Institute of Research, Silver Spring, MD, USA
| | - Emil Lesho
- Walter Reed Army Institute of Research, Silver Spring, MD, USA
| | - Patrick McGann
- Walter Reed Army Institute of Research, Silver Spring, MD, USA
| | - Alexander J McAdam
- Division of Infectious Diseases, Department of Pediatrics, Boston Children's Hospital, Boston, MA, USA
- Harvard Medical School, Boston, MA, USA
- Department of Laboratory Medicine, Boston Children's Hospital, Boston, MA, USA
| | - Thomas J Sandora
- Division of Infectious Diseases, Department of Pediatrics, Boston Children's Hospital, Boston, MA, USA.
- Harvard Medical School, Boston, MA, USA.
| | - Roy Kishony
- Department of Biology, Technion-Israel Institute of Technology, Haifa, Israel.
- Department of Computer Science, Technion-Israel Institute of Technology, Haifa, Israel.
| | - Gregory P Priebe
- Division of Infectious Diseases, Department of Pediatrics, Boston Children's Hospital, Boston, MA, USA.
- Harvard Medical School, Boston, MA, USA.
- Division of Critical Care Medicine, Department of Anesthesiology, Critical Care and Pain Medicine, Boston Children's Hospital, Boston, MA, USA.
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22
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Shi J, Feng Y. [New inhibitors targeting bacterial RNA polymerase]. Zhejiang Da Xue Xue Bao Yi Xue Ban 2019; 48:44-49. [PMID: 31102357 PMCID: PMC8800650 DOI: 10.3785/j.issn.1008-9292.2019.02.08] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2018] [Accepted: 09/05/2018] [Indexed: 06/09/2023]
Abstract
Rifamycins, a group of bacterial RNA polymerase inhibitors, are the firstline antimicrobial drugs to treat tuberculosis. In light of the emergence of rifamycinresistant bacteria, development of new RNA polymerase inhibitors that kill rifamycinresistant bacteria with high bioavailability is urgent. Structural analysis of bacterial RNA polymerase in complex with inhibitors by crystallography and cryo-EM indicates that RNA polymerase inhibitors function through five distinct molecular mechanisms:inhibition of the extension of short RNA; competition with substrates; inhibition of the conformational change of the'bridge helix'; inhibition of clamp opening;inhibition of clamp closure. This article reviews the research progress of these five groups of RNA polymerase inhibitors to provide references for the modification of existing RNA polymerase inhibitors and the discovery of new RNA polymerase inhibitors.
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Affiliation(s)
- Jing Shi
- Department of Biophysics, Zhejiang University School of Medicine, Hangzhou 310058, China
| | - Yu Feng
- Department of Biophysics, Zhejiang University School of Medicine, Hangzhou 310058, China
- Department of Pathology, Sir Run Run Shaw Hospital, Zhejiang University School of Medicine, Hangzhou 310016, China
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23
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Pyta K, Janas A, Szukowska M, Pecyna P, Jaworska M, Gajecka M, Bartl F, Przybylski P. Synthesis, docking and antibacterial studies of more potent amine and hydrazone rifamycin congeners than rifampicin. Eur J Med Chem 2019; 167:96-104. [PMID: 30769243 DOI: 10.1016/j.ejmech.2019.02.009] [Citation(s) in RCA: 27] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2018] [Revised: 01/18/2019] [Accepted: 02/03/2019] [Indexed: 12/24/2022]
Abstract
New rifamycin congeners (1-33) with incorporated amine and hydrazone substituents leading to lipophilic and/or basic nature and altered rigidity of modified C(3) arm were synthesized and structurally characterized in detail. NMR spectroscopic studies at different temperatures indicate two types of structures of rifamycin congeners that are realized in solution: zwitterionic and non-ionic forms in dependence of the basicity of modified C(3) arm. The presence of rifamycin congeners in these two possible forms has a significant impact on the physico-chemical parameters such as lipophilicity (clogP) and water solubility and different binding mode of the C(3) arm of antibiotic at RNAP binding pocket (molecular target) leading to different antibacterial potency. The highest antibacterial potency against S. aureus (including MRSA and MLSB strains) and S. epidermidis strains, even higher than reference rifampicin (Rif) and rifaximin (Rifx) antibiotics, was found for rifamycin congeners bearing at the C(3) arm relatively rigid and basic substituents (bipiperidine and guanidine groups). These modifications provide favorable docking mode and excellent water solubility resulting in high potency (MICs 0.0078 μg/mL what gives ∼ 8.5 nM), irrespective whether rifamycin congener is a tertiary amine (15) or hydrazone (29). In turn, for a higher antibacterial potency of rifamycin congeners against E. faecalis strain (MICs 0.5 μg/mL that is 0.6 μM) as compared to Rif and Rifx, the most crucial factors are: bulkiness and the lipophilic character of the end of the C(3) rebuilt arm.
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Affiliation(s)
- Krystian Pyta
- Faculty of Chemistry, A. Mickiewicz University, Umultowska 89b, 61-614, Poznan, Poland
| | - Anna Janas
- Faculty of Chemistry, A. Mickiewicz University, Umultowska 89b, 61-614, Poznan, Poland
| | - Monika Szukowska
- Faculty of Chemistry, A. Mickiewicz University, Umultowska 89b, 61-614, Poznan, Poland
| | - Paulina Pecyna
- Department of Genetics and Pharmaceutical Microbiology, University of Medical Sciences, Swiecickiego 4, 60-781, Poznan, Poland
| | - Marcelina Jaworska
- Department of Genetics and Pharmaceutical Microbiology, University of Medical Sciences, Swiecickiego 4, 60-781, Poznan, Poland
| | - Marzena Gajecka
- Department of Genetics and Pharmaceutical Microbiology, University of Medical Sciences, Swiecickiego 4, 60-781, Poznan, Poland; Institute of Human Genetics, Polish Academy of Sciences, Strzeszynska 32, 60-479, Poznan, Poland
| | - Franz Bartl
- Humboldt-Universität zu Berlin, Lebenswissenschaftliche Fakultät, Institut für Biologie, Biophysikalische Chemie, Invalidenstr. 42, 10099, Berlin, Germany
| | - Piotr Przybylski
- Faculty of Chemistry, A. Mickiewicz University, Umultowska 89b, 61-614, Poznan, Poland.
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24
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Mechanisms of antibiotics inhibiting bacterial RNA polymerase. Biochem Soc Trans 2019; 47:339-350. [PMID: 30647141 DOI: 10.1042/bst20180499] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2018] [Revised: 12/18/2018] [Accepted: 12/20/2018] [Indexed: 12/21/2022]
Abstract
Transcription, the first phase of gene expression, is performed by the multi-subunit RNA polymerase (RNAP). Bacterial RNAP is a validated target for clinical antibiotics. Many natural and synthetic compounds are now known to target RNAP, inhibiting various stages of the transcription cycle. However, very few RNAP inhibitors are used clinically. A detailed knowledge of inhibitors and their mechanisms of action (MOA) is vital for the future development of efficacious antibiotics. Moreover, inhibitors of RNAP are often useful tools with which to dissect RNAP function. Here, we review the MOA of antimicrobial transcription inhibitors.
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25
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Adeniji AA, Aremu OS, Babalola OO. Selecting lipopeptide-producing, Fusarium-suppressing Bacillus spp.: Metabolomic and genomic probing of Bacillus velezensis NWUMFkBS10.5. Microbiologyopen 2018; 8:e00742. [PMID: 30358165 PMCID: PMC6562122 DOI: 10.1002/mbo3.742] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2018] [Revised: 09/03/2018] [Accepted: 09/10/2018] [Indexed: 12/29/2022] Open
Abstract
The results of this study indicate that the maize rhizosphere remains a reservoir for microbial strains with unique beneficial properties. The study sought to provide an indigenous Bacillus strain with a bioprotective potential to alleviate maize fusariosis in South Africa. We selected seven Bacillus isolates (MORWBS1.1, MARBS2.7, VERBS5.5, MOREBS6.3, MOLBS8.5, MOLBS8.6, and NWUMFkBS10.5) with biosuppressive effects against two maize fungal pathogens (Fusarium graminearum and Fusarium culmorum) based on 16S rDNA gene characterization and lipopeptide gene analysis. The PCR analysis revealed that lipopeptide genes encoding the synthesis of iturin, surfactin, and fengycin might be responsible for their antifungal activities. Few of the isolates also showed possible biosurfactant capability, and their susceptibility to known antibiotics is indicative of their eco‐friendly attributes. In addition, in silico genomic analysis of our best isolate (Bacillus velezensis NWUMFkBS10.5) and characterization of its active metabolite with FTIR, NMR, and ESI‐Micro‐Tof MS confirmed the presence of valuable genes clusters and metabolic pathways. The versatile genomic potential of our Bacillus isolate emphasizes the continued relevance of Bacillus spp. in biological management of plant diseases.
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Affiliation(s)
- Adetomiwa Ayodele Adeniji
- Department of Biological Sciences, Faculty of Natural and Agriculture Science, North-West University, Mmabatho, South Africa.,Food Security and Safety Niche Area, Faculty of Natural and Agriculture Science, North-West University, Mmabatho, South Africa
| | - Oluwole Samuel Aremu
- Department of Chemistry, Faculty of Natural and Agriculture Science, North-West University, Mmabatho, South Africa
| | - Olubukola Oluranti Babalola
- Department of Biological Sciences, Faculty of Natural and Agriculture Science, North-West University, Mmabatho, South Africa.,Food Security and Safety Niche Area, Faculty of Natural and Agriculture Science, North-West University, Mmabatho, South Africa
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26
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Mosaei H, Molodtsov V, Kepplinger B, Harbottle J, Moon CW, Jeeves RE, Ceccaroni L, Shin Y, Morton-Laing S, Marrs ECL, Wills C, Clegg W, Yuzenkova Y, Perry JD, Bacon J, Errington J, Allenby NEE, Hall MJ, Murakami KS, Zenkin N. Mode of Action of Kanglemycin A, an Ansamycin Natural Product that Is Active against Rifampicin-Resistant Mycobacterium tuberculosis. Mol Cell 2018; 72:263-274.e5. [PMID: 30244835 PMCID: PMC6202310 DOI: 10.1016/j.molcel.2018.08.028] [Citation(s) in RCA: 43] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2018] [Revised: 07/19/2018] [Accepted: 08/17/2018] [Indexed: 01/07/2023]
Abstract
Antibiotic-resistant bacterial pathogens pose an urgent healthcare threat, prompting a demand for new medicines. We report the mode of action of the natural ansamycin antibiotic kanglemycin A (KglA). KglA binds bacterial RNA polymerase at the rifampicin-binding pocket but maintains potency against RNA polymerases containing rifampicin-resistant mutations. KglA has antibiotic activity against rifampicin-resistant Gram-positive bacteria and multidrug-resistant Mycobacterium tuberculosis (MDR-M. tuberculosis). The X-ray crystal structures of KglA with the Escherichia coli RNA polymerase holoenzyme and Thermus thermophilus RNA polymerase-promoter complex reveal an altered-compared with rifampicin-conformation of KglA within the rifampicin-binding pocket. Unique deoxysugar and succinate ansa bridge substituents make additional contacts with a separate, hydrophobic pocket of RNA polymerase and preclude the formation of initial dinucleotides, respectively. Previous ansa-chain modifications in the rifamycin series have proven unsuccessful. Thus, KglA represents a key starting point for the development of a new class of ansa-chain derivatized ansamycins to tackle rifampicin resistance.
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Affiliation(s)
- Hamed Mosaei
- Centre for Bacterial Cell Biology, Institute for Cell and Molecular Biosciences, Newcastle University, Newcastle upon Tyne NE2 4AX, UK
| | - Vadim Molodtsov
- Department of Biochemistry and Molecular Biology, The Center for RNA Molecular Biology, Pennsylvania State University, University Park, PA 16802, USA
| | - Bernhard Kepplinger
- Centre for Bacterial Cell Biology, Institute for Cell and Molecular Biosciences, Newcastle University, Newcastle upon Tyne NE2 4AX, UK,Demuris Limited, Newcastle Biomedicine Bio-Incubators, Framlington Place, Newcastle upon Tyne NE2 4HH, UK
| | - John Harbottle
- Centre for Bacterial Cell Biology, Institute for Cell and Molecular Biosciences, Newcastle University, Newcastle upon Tyne NE2 4AX, UK
| | - Christopher William Moon
- TB Research Group, National Infection Service, Public Health England, Manor Farm Road, Porton, Salisbury SP4 0JG, UK
| | - Rose Elizabeth Jeeves
- TB Research Group, National Infection Service, Public Health England, Manor Farm Road, Porton, Salisbury SP4 0JG, UK
| | - Lucia Ceccaroni
- Centre for Bacterial Cell Biology, Institute for Cell and Molecular Biosciences, Newcastle University, Newcastle upon Tyne NE2 4AX, UK
| | - Yeonoh Shin
- Department of Biochemistry and Molecular Biology, The Center for RNA Molecular Biology, Pennsylvania State University, University Park, PA 16802, USA
| | - Stephanie Morton-Laing
- Chemistry, School of Natural and Environmental Sciences, Newcastle University, Newcastle upon Tyne NE1 7RU, UK
| | | | - Corinne Wills
- Chemistry, School of Natural and Environmental Sciences, Newcastle University, Newcastle upon Tyne NE1 7RU, UK
| | - William Clegg
- Chemistry, School of Natural and Environmental Sciences, Newcastle University, Newcastle upon Tyne NE1 7RU, UK
| | - Yulia Yuzenkova
- Centre for Bacterial Cell Biology, Institute for Cell and Molecular Biosciences, Newcastle University, Newcastle upon Tyne NE2 4AX, UK
| | - John David Perry
- Microbiology Department, Freeman Hospital, Newcastle upon Tyne NE7 7DN, UK
| | - Joanna Bacon
- TB Research Group, National Infection Service, Public Health England, Manor Farm Road, Porton, Salisbury SP4 0JG, UK
| | - Jeff Errington
- Centre for Bacterial Cell Biology, Institute for Cell and Molecular Biosciences, Newcastle University, Newcastle upon Tyne NE2 4AX, UK,Demuris Limited, Newcastle Biomedicine Bio-Incubators, Framlington Place, Newcastle upon Tyne NE2 4HH, UK
| | | | - Michael John Hall
- Chemistry, School of Natural and Environmental Sciences, Newcastle University, Newcastle upon Tyne NE1 7RU, UK
| | - Katsuhiko S. Murakami
- Department of Biochemistry and Molecular Biology, The Center for RNA Molecular Biology, Pennsylvania State University, University Park, PA 16802, USA,Corresponding author
| | - Nikolay Zenkin
- Centre for Bacterial Cell Biology, Institute for Cell and Molecular Biosciences, Newcastle University, Newcastle upon Tyne NE2 4AX, UK,Corresponding author
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27
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Portelli S, Phelan JE, Ascher DB, Clark TG, Furnham N. Understanding molecular consequences of putative drug resistant mutations in Mycobacterium tuberculosis. Sci Rep 2018; 8:15356. [PMID: 30337649 PMCID: PMC6193939 DOI: 10.1038/s41598-018-33370-6] [Citation(s) in RCA: 52] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2018] [Accepted: 09/26/2018] [Indexed: 12/21/2022] Open
Abstract
Genomic studies of Mycobacterium tuberculosis bacteria have revealed loci associated with resistance to anti-tuberculosis drugs. However, the molecular consequences of polymorphism within these candidate loci remain poorly understood. To address this, we have used computational tools to quantify the effects of point mutations conferring resistance to three major anti-tuberculosis drugs, isoniazid (n = 189), rifampicin (n = 201) and D-cycloserine (n = 48), within their primary targets, katG, rpoB, and alr. Notably, mild biophysical effects brought about by high incidence mutations were considered more tolerable, while different structural effects brought about by haplotype combinations reflected differences in their functional importance. Additionally, highly destabilising mutations such as alr Y388, highlighted a functional importance of the wildtype residue. Our qualitative analysis enabled us to relate resistance mutations onto a theoretical landscape linking enthalpic changes with phenotype. Such insights will aid the development of new resistance-resistant drugs and, via an integration into predictive tools, in pathogen surveillance.
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Affiliation(s)
- Stephanie Portelli
- Department of Biochemistry and Molecular Biology, Bio21 Institute, University of Melbourne, Victoria, 3051, Australia
| | - Jody E Phelan
- Department of Pathogen Molecular Biology, London School of Hygiene and Tropical Medicine, Keppel Street, London, WC1E 7HT, UK
| | - David B Ascher
- Department of Biochemistry and Molecular Biology, Bio21 Institute, University of Melbourne, Victoria, 3051, Australia
| | - Taane G Clark
- Department of Pathogen Molecular Biology, London School of Hygiene and Tropical Medicine, Keppel Street, London, WC1E 7HT, UK
- Department of Infectious Disease Epidemiology, London School of Hygiene and Tropical Medicine, Keppel Street, London, WC1E 7HT, UK
| | - Nicholas Furnham
- Department of Pathogen Molecular Biology, London School of Hygiene and Tropical Medicine, Keppel Street, London, WC1E 7HT, UK.
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28
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Ehsani S, van den Boom M, Gilpin C, Dara M. The role of novel molecular techniques for tuberculosis diagnostics in the WHO European Region. J Public Health (Oxf) 2018; 38:824-825. [PMID: 28158739 DOI: 10.1093/pubmed/fdv200] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Affiliation(s)
- Soudeh Ehsani
- WHO Regional Office For Europe, Joint Tuberculosis, HIV/AIDS and Hepatitis Programme (JTH), Division of Communicable Diseases, Health Security and Environment, UN City, Marmorvej 51, DK-2100 Copenhagen, Denmark
| | - Martin van den Boom
- WHO Regional Office For Europe, Joint Tuberculosis, HIV/AIDS and Hepatitis Programme (JTH), Division of Communicable Diseases, Health Security and Environment, UN City, Marmorvej 51, DK-2100 Copenhagen, Denmark
| | - Christopher Gilpin
- WHO Global TB Programme (GTB), 20, Avenue Appia, CH-1211, Geneva, Switzerland
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29
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Lin W, Das K, Degen D, Mazumder A, Duchi D, Wang D, Ebright YW, Ebright RY, Sineva E, Gigliotti M, Srivastava A, Mandal S, Jiang Y, Liu Y, Yin R, Zhang Z, Eng ET, Thomas D, Donadio S, Zhang H, Zhang C, Kapanidis AN, Ebright RH. Structural Basis of Transcription Inhibition by Fidaxomicin (Lipiarmycin A3). Mol Cell 2018; 70:60-71.e15. [PMID: 29606590 PMCID: PMC6205224 DOI: 10.1016/j.molcel.2018.02.026] [Citation(s) in RCA: 62] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2018] [Revised: 02/14/2018] [Accepted: 02/23/2018] [Indexed: 12/16/2022]
Abstract
Fidaxomicin is an antibacterial drug in clinical use for treatment of Clostridium difficile diarrhea. The active ingredient of fidaxomicin, lipiarmycin A3 (Lpm), functions by inhibiting bacterial RNA polymerase (RNAP). Here we report a cryo-EM structure of Mycobacterium tuberculosis RNAP holoenzyme in complex with Lpm at 3.5-Å resolution. The structure shows that Lpm binds at the base of the RNAP "clamp." The structure exhibits an open conformation of the RNAP clamp, suggesting that Lpm traps an open-clamp state. Single-molecule fluorescence resonance energy transfer experiments confirm that Lpm traps an open-clamp state and define effects of Lpm on clamp dynamics. We suggest that Lpm inhibits transcription by trapping an open-clamp state, preventing simultaneous interaction with promoter -10 and -35 elements. The results account for the absence of cross-resistance between Lpm and other RNAP inhibitors, account for structure-activity relationships of Lpm derivatives, and enable structure-based design of improved Lpm derivatives.
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Affiliation(s)
- Wei Lin
- Waksman Institute and Department of Chemistry, Rutgers University, Piscataway, NJ 08854, USA
| | - Kalyan Das
- Rega Institute and Department of Microbiology and Immunology, KU Leuven, 3000 Leuven, Belgium.
| | - David Degen
- Waksman Institute and Department of Chemistry, Rutgers University, Piscataway, NJ 08854, USA
| | - Abhishek Mazumder
- Waksman Institute and Department of Chemistry, Rutgers University, Piscataway, NJ 08854, USA
| | - Diego Duchi
- Department of Physics, University of Oxford, Oxford OX1 3PU, UK
| | - Dongye Wang
- Waksman Institute and Department of Chemistry, Rutgers University, Piscataway, NJ 08854, USA
| | - Yon W Ebright
- Waksman Institute and Department of Chemistry, Rutgers University, Piscataway, NJ 08854, USA
| | - Richard Y Ebright
- Waksman Institute and Department of Chemistry, Rutgers University, Piscataway, NJ 08854, USA
| | - Elena Sineva
- Waksman Institute and Department of Chemistry, Rutgers University, Piscataway, NJ 08854, USA
| | - Matthew Gigliotti
- Waksman Institute and Department of Chemistry, Rutgers University, Piscataway, NJ 08854, USA
| | - Aashish Srivastava
- Waksman Institute and Department of Chemistry, Rutgers University, Piscataway, NJ 08854, USA
| | - Sukhendu Mandal
- Waksman Institute and Department of Chemistry, Rutgers University, Piscataway, NJ 08854, USA
| | - Yi Jiang
- Waksman Institute and Department of Chemistry, Rutgers University, Piscataway, NJ 08854, USA
| | - Yu Liu
- Waksman Institute and Department of Chemistry, Rutgers University, Piscataway, NJ 08854, USA
| | - Ruiheng Yin
- Waksman Institute and Department of Chemistry, Rutgers University, Piscataway, NJ 08854, USA
| | - Zhening Zhang
- The National Resource for Automated Molecular Microscopy, Simons Electron Microscopy Center, New York Structural Biology Center, New York NY 10027, USA
| | - Edward T Eng
- The National Resource for Automated Molecular Microscopy, Simons Electron Microscopy Center, New York Structural Biology Center, New York NY 10027, USA
| | - Dennis Thomas
- Center for Integrative Proteomics, Rutgers University, Piscataway, NJ 08854, USA
| | | | - Haibo Zhang
- South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou 510301, China
| | - Changsheng Zhang
- South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou 510301, China
| | | | - Richard H Ebright
- Waksman Institute and Department of Chemistry, Rutgers University, Piscataway, NJ 08854, USA.
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30
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Raghavan S, Nyalata S. A short convergent synthesis of the [3.2.1]dioxabicyclooctane subunit of sorangicin A via regioselective epoxide opening. Tetrahedron 2018. [DOI: 10.1016/j.tet.2018.01.036] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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31
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Almeida S, Dorneles EMS, Diniz C, Abreu V, Sousa C, Alves J, Carneiro A, Bagano P, Spier S, Barh D, Lage AP, Figueiredo H, Azevedo V. Quadruplex PCR assay for identification of Corynebacterium pseudotuberculosis differentiating biovar Ovis and Equi. BMC Vet Res 2017; 13:290. [PMID: 28946887 PMCID: PMC5613524 DOI: 10.1186/s12917-017-1210-5] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2016] [Accepted: 09/14/2017] [Indexed: 01/21/2023] Open
Abstract
BACKGROUND Corynebacterium pseudotuberculosis is classified into two biovars, nitrate-negative biovar Ovis which is the etiologic agent of caseous lymphadenitis in small ruminants and nitrate-positive biovar Equi, which causes abscesses and ulcerative lymphangitis in equines. The aim of this study was to develop a quadruplex PCR assay that would allow simultaneous detection and biovar-typing of C. pseudotuberculosis. METHODS In the present study, genomes of C. pseudotuberculosis strains were used to identify the genes involved in the nitrate reduction pathway to improve a species identification three-primer multiplex PCR assay. The nitrate reductase gene (narG) was included in the PCR assay along with the 16S, rpoB and pld genes to enhance the diagnosis of the multiplex PCR at biovar level. RESULTS A novel quadruplex PCR assay for C. pseudotuberculosis species and biovar identification was developed. The results of the quadruplex PCR of 348 strains, 346 previously well-characterized clinical isolates of C. pseudotuberculosis from different hosts (goats, sheep, horse, cattle, buffalo, llamas and humans), the vaccine strain 1002 and the type strain ATCC 19410T, were compared to the results of nitrate reductase identification by biochemical test. The McNemar's Chi-squared test used to compare the two methods used for C. pseudotuberculosis biovar identification showed no significant difference (P = 0.75) [95% CI for odds ratio (0.16-6.14)] between the quadruplex PCR and the nitrate biochemical test. Concordant results were observed for 97.13% (338 / 348) of the tested strains and the kappa value was 0.94 [95% CI (0.90-0.98)]. CONCLUSIONS The ability of the quadruplex assay to discriminate between C. pseudotuberculosis biovar Ovis and Equi strains enhances its usefulness in the clinical microbiology laboratory.
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Affiliation(s)
- Sintia Almeida
- Instituto de Ciências Biológicas, Federal University of Minas Gerais, Belo Horizonte, MG Brazil
| | - Elaine M. S. Dorneles
- Escola de Veterinária, Federal University of Minas Gerais, Belo Horizonte, MG Brazil
| | - Carlos Diniz
- Instituto de Ciências Biológicas, Federal University of Minas Gerais, Belo Horizonte, MG Brazil
- Departamento de Medicina Veterinária, Federal University of Lavras, Lavras, MG Brazil
| | - Vinícius Abreu
- Centro de Energia Nuclear na Agricultura, University of Sao Paulo, Piracicaba, SP Brazil
| | - Cassiana Sousa
- Instituto de Ciências Biológicas, Federal University of Minas Gerais, Belo Horizonte, MG Brazil
| | - Jorianne Alves
- Instituto de Ciências Biológicas, Federal University of Para, Belém, PA Brazil
| | - Adriana Carneiro
- Instituto de Ciências Biológicas, Federal University of Para, Belém, PA Brazil
| | - Priscilla Bagano
- Instituto de Ciências Biológicas, Federal University of Minas Gerais, Belo Horizonte, MG Brazil
| | - Sharon Spier
- Department of Medicine and Epidemiology, UC Davis School of Veterinary Medicine, Davis, CA USA
| | - Debmalya Barh
- Instituto de Ciências Biológicas, Federal University of Minas Gerais, Belo Horizonte, MG Brazil
- Centre for Genomics and Applied Gene Technology, Institute of Integrative Omics and Applied Biotechnology (IIOAB), Nonakuri, Purba Medinipur, WB India
| | - Andrey P. Lage
- Escola de Veterinária, Federal University of Minas Gerais, Belo Horizonte, MG Brazil
| | - Henrique Figueiredo
- Aquacen - National Reference Laboratory for Aquatic Animal Diseases, Federal University of Minas Gerais, Belo Horizonte, MG Brazil
| | - Vasco Azevedo
- Instituto de Ciências Biológicas, Federal University of Minas Gerais, Belo Horizonte, MG Brazil
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Masschelein J, Jenner M, Challis GL. Antibiotics from Gram-negative bacteria: a comprehensive overview and selected biosynthetic highlights. Nat Prod Rep 2017. [PMID: 28650032 DOI: 10.1039/c7np00010c] [Citation(s) in RCA: 64] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Covering: up to 2017The overwhelming majority of antibiotics in clinical use originate from Gram-positive Actinobacteria. In recent years, however, Gram-negative bacteria have become increasingly recognised as a rich yet underexplored source of novel antimicrobials, with the potential to combat the looming health threat posed by antibiotic resistance. In this article, we have compiled a comprehensive list of natural products with antimicrobial activity from Gram-negative bacteria, including information on their biosynthetic origin(s) and molecular target(s), where known. We also provide a detailed discussion of several unusual pathways for antibiotic biosynthesis in Gram-negative bacteria, serving to highlight the exceptional biocatalytic repertoire of this group of microorganisms.
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Affiliation(s)
- J Masschelein
- Department of Chemistry, University of Warwick, Gibbet Hill Road, Coventry, UK.
| | - M Jenner
- Department of Chemistry, University of Warwick, Gibbet Hill Road, Coventry, UK.
| | - G L Challis
- Department of Chemistry, University of Warwick, Gibbet Hill Road, Coventry, UK.
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Molodtsov V, Scharf NT, Stefan MA, Garcia GA, Murakami KS. Structural basis for rifamycin resistance of bacterial RNA polymerase by the three most clinically important RpoB mutations found in Mycobacterium tuberculosis. Mol Microbiol 2017; 103:1034-1045. [PMID: 28009073 DOI: 10.1111/mmi.13606] [Citation(s) in RCA: 67] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 12/08/2016] [Indexed: 12/01/2022]
Abstract
Since 1967, Rifampin (RMP, a Rifamycin) has been used as a first line antibiotic treatment for tuberculosis (TB), and it remains the cornerstone of current short-term TB treatment. Increased occurrence of Rifamycin-resistant (RIFR ) TB, ∼41% of which results from the RpoB S531L mutation in RNA polymerase (RNAP), has become a growing problem worldwide. In this study, we determined the X-ray crystal structures of the Escherichia coli RNAPs containing the most clinically important S531L mutation and two other frequently observed RIFR mutants, RpoB D516V and RpoB H526Y. The structures reveal that the S531L mutation imparts subtle if any structural or functional impact on RNAP in the absence of RIF. However, upon RMP binding, the S531L mutant exhibits a disordering of the RIF binding interface, which effectively reduces the RMP affinity. In contrast, the H526Y mutation reshapes the RIF binding pocket, generating significant steric conflicts that essentially prevent any RIF binding. While the D516V mutant does not exhibit any such gross structural changes, certainly the electrostatic surface of the RIF binding pocket is dramatically changed, likely resulting in the decreased affinity for RIFs. Analysis of interactions of RMP with three common RIFR mutant RNAPs suggests that modifications to RMP may recover its efficacy against RIFR TB.
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Affiliation(s)
- Vadim Molodtsov
- Department of Biochemistry and Molecular Biology, The Center for RNA Molecular Biology, The Pennsylvania State University, University Park, PA, 16802, USA
| | - Nathan T Scharf
- Department of Medicinal Chemistry, College of Pharmacy, University of Michigan, 428 Church St, Ann Arbor, MI, 48109-1065, USA
| | - Maxwell A Stefan
- Department of Medicinal Chemistry, College of Pharmacy, University of Michigan, 428 Church St, Ann Arbor, MI, 48109-1065, USA
| | - George A Garcia
- Department of Medicinal Chemistry, College of Pharmacy, University of Michigan, 428 Church St, Ann Arbor, MI, 48109-1065, USA
| | - Katsuhiko S Murakami
- Department of Biochemistry and Molecular Biology, The Center for RNA Molecular Biology, The Pennsylvania State University, University Park, PA, 16802, USA
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New antibiotics from Nature’s chemical inventory. Bioorg Med Chem 2016; 24:6227-6252. [DOI: 10.1016/j.bmc.2016.09.014] [Citation(s) in RCA: 50] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2016] [Accepted: 09/07/2016] [Indexed: 01/07/2023]
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Lee J, Borukhov S. Bacterial RNA Polymerase-DNA Interaction-The Driving Force of Gene Expression and the Target for Drug Action. Front Mol Biosci 2016; 3:73. [PMID: 27882317 PMCID: PMC5101437 DOI: 10.3389/fmolb.2016.00073] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2016] [Accepted: 10/24/2016] [Indexed: 11/17/2022] Open
Abstract
DNA-dependent multisubunit RNA polymerase (RNAP) is the key enzyme of gene expression and a target of regulation in all kingdoms of life. It is a complex multifunctional molecular machine which, unlike other DNA-binding proteins, engages in extensive and dynamic interactions (both specific and nonspecific) with DNA, and maintains them over a distance. These interactions are controlled by DNA sequences, DNA topology, and a host of regulatory factors. Here, we summarize key recent structural and biochemical studies that elucidate the fine details of RNAP-DNA interactions during initiation. The findings of these studies help unravel the molecular mechanisms of promoter recognition and open complex formation, initiation of transcript synthesis and promoter escape. We also discuss most current advances in the studies of drugs that specifically target RNAP-DNA interactions during transcription initiation and elongation.
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Affiliation(s)
- Jookyung Lee
- Department of Cell Biology, Rowan University School of Osteopathic Medicine Stratford, NJ, USA
| | - Sergei Borukhov
- Department of Cell Biology, Rowan University School of Osteopathic Medicine Stratford, NJ, USA
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Montaña ÁM, Corominas A, Chesa JF, García F, Font-Bardia M. Regio- and Stereoselective Synthesis of Acetallic Tetrahydropyrans as Building Blocks for Natural Products Preparation, via a Tandem [4+3]-Cycloaddition/Ozonolysis Process. European J Org Chem 2016. [DOI: 10.1002/ejoc.201600590] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- Ángel M. Montaña
- Industrial and Applied Organic Chemistry Research Unity; Department of Organic Chemistry; University of Barcelona; Martí Franquès 1-11 08028 Barcelona Spain
| | - Albert Corominas
- Industrial and Applied Organic Chemistry Research Unity; Department of Organic Chemistry; University of Barcelona; Martí Franquès 1-11 08028 Barcelona Spain
| | - Juan F. Chesa
- Industrial and Applied Organic Chemistry Research Unity; Department of Organic Chemistry; University of Barcelona; Martí Franquès 1-11 08028 Barcelona Spain
| | - Francisca García
- Industrial and Applied Organic Chemistry Research Unity; Department of Organic Chemistry; University of Barcelona; Martí Franquès 1-11 08028 Barcelona Spain
| | - Mercè Font-Bardia
- X-ray Diffraction Unit. Scientific and Technologic Centers of the University of Barcelona (CCiTUB); University of Barcelona; Solé i Sabarís 1-3 08028 Barcelona Spain
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Rifampicin resistance mutations in the 81 bp RRDR of rpoB gene in Mycobacterium tuberculosis clinical isolates using Xpert MTB/RIF in Khyber Pakhtunkhwa, Pakistan: a retrospective study. BMC Infect Dis 2016; 16:413. [PMID: 27519406 PMCID: PMC4983047 DOI: 10.1186/s12879-016-1745-2] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2015] [Accepted: 08/03/2016] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Multi-drug resistant tuberculosis (MDR-TB) is a major public health problem especially in developing countries. World Health Organization (WHO) recommends use of Xpert MTB/RIF assay to simultaneously detecting Mycobacterium tuberculosis (MTB) and rifampicin (RIF) resistance. The primary objective of this study was to determine the frequency of MDR-TB in patients suspected to have drug resistance in Khyber Pakhtunkhwa. The frequency of probes for various rpoB gene mutations using Xpert MTB/RIF assay within 81 bp RRDR (Rifampicin Resistance Determining Region) was the secondary objective. METHODS A total of 2391 specimens, received at Programmatic Management of Drug Resistant TB (PMDT) Unit, Lady Reading Hospital (LRH) Peshawar, Pakistan, between October 2011 and December 2014, were analyzed by Xpert MTB/RIF test. MTB positive with rifampicin resistance were further analyzed to first line anti-mycobacterial drug susceptibility testing (DST) using middle brook 7H10 medium. The data was analyzed using statistical software; SPSS version 18. RESULTS Out of 2391 specimens, 1408 (59 %) were found positive for MTB and among them, 408 (29 %) showed rifampicin-resistance with four different rpoB gene mutations within 81 bp RRDR. The frequency of various probes among RIF-resistant isolates was observed as: probe E, in 314 out of 408 isolates; B, 44 out of 408; A, 5 out of 408; D, 34 out of 408; and probe C was observed among 6 out of 408 RIF-resistant isolates. The probe A&B and E&D mutation combination was found in only 1 isolate in each case, while B&D mutation combination was detected among 3 out of 408 RIF-resistant isolates. CONCLUSIONS Hence, it is concluded from our study on a selected population, 29 % of patients had MDR-TB. Probe E related mutations (also known as codon 531and 533) were the most common rpoB genetic mutation [314 (77 %)], acknowledged by Xpert MTB/RIF assay. Least mutation was detected within the sequence 511 (1.2 %).
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Nusrath Unissa A, Hassan S, Indira Kumari V, Revathy R, Hanna LE. Insights into RpoB clinical mutants in mediating rifampicin resistance in Mycobacterium tuberculosis. J Mol Graph Model 2016; 67:20-32. [DOI: 10.1016/j.jmgm.2016.04.005] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2015] [Revised: 03/25/2016] [Accepted: 04/18/2016] [Indexed: 11/29/2022]
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Korsak D, Krawczyk-Balska A. Rifampicin- and Rifabutin-Resistant Listeria monocytogenes Strains Isolated from Food Products Carry Mutations in rpoB Gene. Foodborne Pathog Dis 2016; 13:363-8. [PMID: 27105395 DOI: 10.1089/fpd.2015.2103] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
The aim of this study was to investigate the mechanism of rifampicin resistance in Listeria monocytogenes strains isolated from different types of food and the impact of specific mutations in the rpoB gene on susceptibility to different antimicrobial agents and on fitness cost. Fifteen spontaneous rifampicin-resistant strains were selected. The DNA regions corresponding to clusters I-II, III, and N-terminal end of the rpoB gene of Escherichia coli were amplified and sequenced, leading to the identification of 10 different substitutions, nine of which (Ser466Pro, Gln470Lys Asp473Asn, Gly479Asp, His483Tyr/Arg/Asp, Arg486His, and Leu490Pro) were located in cluster I and one (Pro521Leu) in cluster II. From among these mutations, substitutions at positions 466, 470, 486, 490, and 521 have not been described for L. monocytogenes. Only substitutions at positions 470, 479, 483, and 486 lead to resistance to very high concentrations of rifampicin (minimum inhibitory concentration [MIC] ≥256 μg/mL) and rifabutin (MIC 128 μg/mL). Furthermore, mutations at positions 473, 490, and 521 had different effects on susceptibility to rifampicin compared to other bacterial species. A correlation between rifampicin resistance and susceptibility to a wide range of antimicrobials was determined. Substitutions in RpoB did not change the susceptibility of the mutants to different antimicrobials. The fitness of the mutants was assessed by paired competition experiments. Mutations at positions 470 and 479 were not associated with a reduction in fitness level. There was no correlation between the MIC of rifampicin and fitness cost. The risk of transmission of resistant strains through the food chain highlights the need for monitoring resistance, identifying mutant organisms, their genotypes, and their altered phenotypes to understand their dissemination.
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Affiliation(s)
- Dorota Korsak
- Department of Applied Microbiology, Institute of Microbiology, Faculty of Biology, University of Warsaw , Warsaw, Poland
| | - Agata Krawczyk-Balska
- Department of Applied Microbiology, Institute of Microbiology, Faculty of Biology, University of Warsaw , Warsaw, Poland
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Czerwonka D, Domagalska J, Pyta K, Kubicka MM, Pecyna P, Gajecka M, Przybylski P. Structure-activity relationship studies of new rifamycins containing l-amino acid esters as inhibitors of bacterial RNA polymerases. Eur J Med Chem 2016; 116:216-221. [PMID: 27061985 DOI: 10.1016/j.ejmech.2016.03.061] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2015] [Revised: 02/19/2016] [Accepted: 03/22/2016] [Indexed: 02/05/2023]
Abstract
New rifamycins (1-12) combined with different l-amino acids, containing methyl, ethyl, tert-butyl and benzyl groups at the ester part, via amine linkage, were synthesized and their structures in solution were determined by spectroscopic FT-IR and 1D and 2D NMR methods as well as visualized by DFT calculations. Two types of rifamycin structures were detected in solution: a zwitterionic one with the transferred proton from O(8)H phenol to secondary N(38) atom and a pseudocyclic structure stabilized via formation of intramolecular H-bond within the protonated basic C(3)-substituent. The presence of these rifamycins' structures influenced physico-chemical (logP, solubility) parameters and antibacterial properties. The bulkiness at the ester substituent of new rifamycins containing aromatic l-amino acids was found to be an important factor, besides the solubility, to achieve relatively high antibacterial activity against reference S. epidermidis and reference S. aureus and MRSA strains (MICs 0.016-0.063 μg/mL), comparable to that of rifampicin. SAR for the novel derivatives was discussed in view of the calculated structures of rifamycin-RNAP complexes.
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Affiliation(s)
- Dominika Czerwonka
- Faculty of Chemistry, A. Mickiewicz University, Umultowska 89b, 61-614 Poznan, Poland
| | - Joanna Domagalska
- Faculty of Chemistry, A. Mickiewicz University, Umultowska 89b, 61-614 Poznan, Poland
| | - Krystian Pyta
- Faculty of Chemistry, A. Mickiewicz University, Umultowska 89b, 61-614 Poznan, Poland
| | - Marcelina M Kubicka
- Department of Genetics and Pharmaceutical Microbiology, University of Medical Sciences, Swiecickiego 4, 60-781 Poznan, Poland
| | - Paulina Pecyna
- Department of Genetics and Pharmaceutical Microbiology, University of Medical Sciences, Swiecickiego 4, 60-781 Poznan, Poland
| | - Marzena Gajecka
- Department of Genetics and Pharmaceutical Microbiology, University of Medical Sciences, Swiecickiego 4, 60-781 Poznan, Poland; Institute of Human Genetics, Polish Academy of Science, Strzeszynska 32, 60-479 Poznan, Poland
| | - Piotr Przybylski
- Faculty of Chemistry, A. Mickiewicz University, Umultowska 89b, 61-614 Poznan, Poland.
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Karwehl S, Jansen R, Huch V, Stadler M. Sorazolons, Carbazole Alkaloids from Sorangium cellulosum Strain Soce375. JOURNAL OF NATURAL PRODUCTS 2016; 79:369-375. [PMID: 26866461 DOI: 10.1021/acs.jnatprod.5b00997] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
Sorazolons A (1) to E2 (9) were isolated from Sorangium cellulosum strain Soce375. Their molecular structures were elucidated using extensive HRESIMS and NMR analysis. The absolute configuration of sorazolon A (1) was determined by comparison of the experimental CD spectrum with quantum chemical calculated spectra for both enantiomers. Sorazolons D2 (7), E (8), and E2 (9) exhibit a moderate cytotoxic activity against mouse fibroblast cell line L929 with IC50 values between 5.0 μM and 0.09 mM.
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Affiliation(s)
- Sabrina Karwehl
- Department of Microbial Drugs, Helmholtz Centre for Infection Research , Inhoffenstraße 7, 38124 Braunschweig, Germany
- German Centre for Infection Research (DZIF), Partner Site Hannover-Braunschweig , Braunschweig, Germany
| | - Rolf Jansen
- Department of Microbial Drugs, Helmholtz Centre for Infection Research , Inhoffenstraße 7, 38124 Braunschweig, Germany
- German Centre for Infection Research (DZIF), Partner Site Hannover-Braunschweig , Braunschweig, Germany
| | - Volker Huch
- Department of Inorganic Chemistry, Saarland University , Building C 4.1, 66123 Saarbrücken, Germany
| | - Marc Stadler
- Department of Microbial Drugs, Helmholtz Centre for Infection Research , Inhoffenstraße 7, 38124 Braunschweig, Germany
- German Centre for Infection Research (DZIF), Partner Site Hannover-Braunschweig , Braunschweig, Germany
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Bacterial Transcription as a Target for Antibacterial Drug Development. Microbiol Mol Biol Rev 2016; 80:139-60. [PMID: 26764017 DOI: 10.1128/mmbr.00055-15] [Citation(s) in RCA: 88] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023] Open
Abstract
Transcription, the first step of gene expression, is carried out by the enzyme RNA polymerase (RNAP) and is regulated through interaction with a series of protein transcription factors. RNAP and its associated transcription factors are highly conserved across the bacterial domain and represent excellent targets for broad-spectrum antibacterial agent discovery. Despite the numerous antibiotics on the market, there are only two series currently approved that target transcription. The determination of the three-dimensional structures of RNAP and transcription complexes at high resolution over the last 15 years has led to renewed interest in targeting this essential process for antibiotic development by utilizing rational structure-based approaches. In this review, we describe the inhibition of the bacterial transcription process with respect to structural studies of RNAP, highlight recent progress toward the discovery of novel transcription inhibitors, and suggest additional potential antibacterial targets for rational drug design.
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Helfrich EJN, Piel J. Biosynthesis of polyketides by trans-AT polyketide synthases. Nat Prod Rep 2016; 33:231-316. [DOI: 10.1039/c5np00125k] [Citation(s) in RCA: 230] [Impact Index Per Article: 28.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
This review discusses the biosynthesis of natural products that are generated bytrans-AT polyketide synthases, a family of catalytically versatile enzymes that represents one of the major group of proteins involved in the production of bioactive polyketides.
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Affiliation(s)
- Eric J. N. Helfrich
- Institute of Microbiology
- Eidgenössische Technische Hochschule (ETH) Zurich
- 8093 Zurich
- Switzerland
| | - Jörn Piel
- Institute of Microbiology
- Eidgenössische Technische Hochschule (ETH) Zurich
- 8093 Zurich
- Switzerland
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44
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References. Antibiotics (Basel) 2015. [DOI: 10.1128/9781555819316.refs] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
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45
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Meftahi N, Namouchi A, Mhenni B, Brandis G, Hughes D, Mardassi H. Evidence for the critical role of a secondary site rpoB mutation in the compensatory evolution and successful transmission of an MDR tuberculosis outbreak strain. J Antimicrob Chemother 2015; 71:324-32. [PMID: 26538504 DOI: 10.1093/jac/dkv345] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2015] [Accepted: 09/24/2015] [Indexed: 01/24/2023] Open
Abstract
BACKGROUND MDR Mycobacterium tuberculosis clinical strains that cause large outbreaks, particularly among HIV-negative patients, are likely to have undergone the most successful compensatory evolution. Hence, mutations secondary to the acquisition of drug resistance are worthy of consideration in these highly transmissible strains. Here, we assessed the role of a mutation within rpoB, rpoB V615M, secondary to the rifampicin resistance-conferring mutation rpoB S531L, which is associated with a major MDR tuberculosis outbreak strain that evolved in an HIV-negative context in northern Tunisia. METHODS Using BCG as a model organism, we engineered strains harbouring either the rpoB S531L mutation alone or the double mutation rpoB S531L, V615M. Individual and competitive in vitro growth assays were performed in order to assess the relative fitness of each BCG mutant. RESULTS The rpoB V615M mutation was found to be invariably associated with rpoB S531L. Structural analysis mapped rpoB V615M to the same bridge helix region as rpoB compensatory mutations previously described in Salmonella. Compared with the rpoB single-mutant BCG, the double mutant displayed improved growth characteristics and fitness rates equivalent to WT BCG. Strikingly, the rpoB double mutation conferred high-level resistance to rifampicin. CONCLUSIONS Here, we demonstrated the fitness compensatory role of a mutation within rpoB, secondary to the rifampicin resistance mutation rpoB S531L, which is characteristic of an MDR M. tuberculosis major outbreak strain. The finding that this secondary mutation concomitantly increased the resistance level to rifampicin argues for its significant contribution to the successful transmission of the MDR-TB strain.
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Affiliation(s)
- Nedra Meftahi
- Unit of Typing & Genetics of Mycobacteria, Laboratory of Molecular Microbiology, Vaccinology, and Biotechnology Development, Institut Pasteur de Tunis, Université de Tunis El Manar, Tunis, Tunisia
| | - Amine Namouchi
- Unit of Typing & Genetics of Mycobacteria, Laboratory of Molecular Microbiology, Vaccinology, and Biotechnology Development, Institut Pasteur de Tunis, Université de Tunis El Manar, Tunis, Tunisia
| | - Besma Mhenni
- Unit of Typing & Genetics of Mycobacteria, Laboratory of Molecular Microbiology, Vaccinology, and Biotechnology Development, Institut Pasteur de Tunis, Université de Tunis El Manar, Tunis, Tunisia
| | - Gerrit Brandis
- Department of Medical Biochemistry and Microbiology, Box 582 Biomedical Center, Uppsala University, Uppsala, Sweden
| | - Diarmaid Hughes
- Department of Medical Biochemistry and Microbiology, Box 582 Biomedical Center, Uppsala University, Uppsala, Sweden
| | - Helmi Mardassi
- Unit of Typing & Genetics of Mycobacteria, Laboratory of Molecular Microbiology, Vaccinology, and Biotechnology Development, Institut Pasteur de Tunis, Université de Tunis El Manar, Tunis, Tunisia
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Suplatov D, Švedas V. Study of Functional and Allosteric Sites in Protein Superfamilies. Acta Naturae 2015; 7:34-45. [PMID: 26798490 PMCID: PMC4717248] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
The interaction of proteins (enzymes) with a variety of low-molecular-weight compounds, as well as protein-protein interactions, is the most important factor in the regulation of their functional properties. To date, research effort has routinely focused on studying ligand binding to the functional sites of proteins (active sites of enzymes), whereas the molecular mechanisms of allosteric regulation, as well as binding to other pockets and cavities in protein structures, remained poorly understood. Recent studies have shown that allostery may be an intrinsic property of virtually all proteins. Novel approaches are needed to systematically analyze the architecture and role of various binding sites and establish the relationship between structure, function, and regulation. Computational biology, bioinformatics, and molecular modeling can be used to search for new regulatory centers, characterize their structural peculiarities, as well as compare different pockets in homologous proteins, study the molecular mechanisms of allostery, and understand the communication between topologically independent binding sites in protein structures. The establishment of an evolutionary relationship between different binding centers within protein superfamilies and the discovery of new functional and allosteric (regulatory) sites using computational approaches can improve our understanding of the structure-function relationship in proteins and provide new opportunities for drug design and enzyme engineering.
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Affiliation(s)
- D. Suplatov
- Lomonosov Moscow State University, Belozersky Institute of Physicochemical Biology, Vorobjev hills 1-40, Moscow 119991, Russia
- Lomonosov Moscow State University, Faculty of Bioengineering and Bioinformatics, Vorobjev hills 1 -73, 119991, Moscow, Russia
| | - V. Švedas
- Lomonosov Moscow State University, Belozersky Institute of Physicochemical Biology, Vorobjev hills 1-40, Moscow 119991, Russia
- Lomonosov Moscow State University, Faculty of Bioengineering and Bioinformatics, Vorobjev hills 1 -73, 119991, Moscow, Russia
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The effect of complexation of 3-formylrifamycin SV macrocyclic ether derivatives with metal cations and small nitrogen-containing organic molecules on antibacterial activity against S. aureus and S. epidermidis. Bioorg Med Chem Lett 2015; 25:3903-9. [DOI: 10.1016/j.bmcl.2015.07.043] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2015] [Revised: 07/15/2015] [Accepted: 07/16/2015] [Indexed: 11/20/2022]
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Petushkov I, Pupov D, Bass I, Kulbachinskiy A. Mutations in the CRE pocket of bacterial RNA polymerase affect multiple steps of transcription. Nucleic Acids Res 2015; 43:5798-809. [PMID: 25990734 PMCID: PMC4499132 DOI: 10.1093/nar/gkv504] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2015] [Accepted: 05/04/2015] [Indexed: 11/13/2022] Open
Abstract
During transcription, the catalytic core of RNA polymerase (RNAP) must interact with the DNA template with low-sequence specificity to ensure efficient enzyme translocation and RNA extension. Unexpectedly, recent structural studies of bacterial promoter complexes revealed specific interactions between the nontemplate DNA strand at the downstream edge of the transcription bubble (CRE, core recognition element) and a protein pocket formed by core RNAP (CRE pocket). We investigated the roles of these interactions in transcription by analyzing point amino acid substitutions and deletions in Escherichia coli RNAP. The mutations affected multiple steps of transcription, including promoter recognition, RNA elongation and termination. In particular, we showed that interactions of the CRE pocket with a nontemplate guanine immediately downstream of the active center stimulate RNA-hairpin-dependent transcription pausing but not other types of pausing. Thus, conformational changes of the elongation complex induced by nascent RNA can modulate CRE effects on transcription. The results highlight the roles of specific core RNAP–DNA interactions at different steps of RNA synthesis and suggest their importance for transcription regulation in various organisms.
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Affiliation(s)
- Ivan Petushkov
- Institute of Molecular Genetics, Russian Academy of Sciences, Kurchatov sq. 2, Moscow 123182, Russia Molecular Biology Department, Biological Faculty, Lomonosov Moscow State University, GSP-1, Leninskie Gory, Moscow 119991, Russia
| | - Danil Pupov
- Institute of Molecular Genetics, Russian Academy of Sciences, Kurchatov sq. 2, Moscow 123182, Russia
| | - Irina Bass
- Institute of Molecular Genetics, Russian Academy of Sciences, Kurchatov sq. 2, Moscow 123182, Russia
| | - Andrey Kulbachinskiy
- Institute of Molecular Genetics, Russian Academy of Sciences, Kurchatov sq. 2, Moscow 123182, Russia Molecular Biology Department, Biological Faculty, Lomonosov Moscow State University, GSP-1, Leninskie Gory, Moscow 119991, Russia
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Structural biology of bacterial RNA polymerase. Biomolecules 2015; 5:848-64. [PMID: 25970587 PMCID: PMC4496699 DOI: 10.3390/biom5020848] [Citation(s) in RCA: 82] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2015] [Revised: 04/10/2015] [Accepted: 04/13/2015] [Indexed: 11/17/2022] Open
Abstract
Since its discovery and characterization in the early 1960s (Hurwitz, J. The discovery of RNA polymerase. J. Biol. Chem. 2005, 280, 42477-42485), an enormous amount of biochemical, biophysical and genetic data has been collected on bacterial RNA polymerase (RNAP). In the late 1990s, structural information pertaining to bacterial RNAP has emerged that provided unprecedented insights into the function and mechanism of RNA transcription. In this review, I list all structures related to bacterial RNAP (as determined by X-ray crystallography and NMR methods available from the Protein Data Bank), describe their contributions to bacterial transcription research and discuss the role that small molecules play in inhibiting bacterial RNA transcription.
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Rifampicin-resistance, rpoB polymorphism and RNA polymerase genetic engineering. J Biotechnol 2015; 202:60-77. [DOI: 10.1016/j.jbiotec.2014.11.024] [Citation(s) in RCA: 65] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2014] [Revised: 11/22/2014] [Accepted: 11/26/2014] [Indexed: 01/22/2023]
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