1
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Identification of a solo acylhomoserine lactone synthase from the myxobacterium Archangium gephyra. Sci Rep 2021; 11:3018. [PMID: 33542315 PMCID: PMC7862692 DOI: 10.1038/s41598-021-82480-1] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2020] [Accepted: 01/20/2021] [Indexed: 12/31/2022] Open
Abstract
Considered a key taxon in soil and marine microbial communities, myxobacteria exist as coordinated swarms that utilize a combination of lytic enzymes and specialized metabolites to facilitate predation of microbes. This capacity to produce specialized metabolites and the associated abundance of biosynthetic pathways contained within their genomes have motivated continued drug discovery efforts from myxobacteria. Of all myxobacterial biosynthetic gene clusters deposited in the antiSMASH database, only one putative acylhomoserine lactone (AHL) synthase, agpI, was observed, in genome data from Archangium gephyra. Without an AHL receptor also apparent in the genome of A. gephyra, we sought to determine if AgpI was an uncommon example of an orphaned AHL synthase. Herein we report the bioinformatic assessment of AgpI and discovery of a second AHL synthase from Vitiosangium sp. During axenic cultivation conditions, no detectible AHL metabolites were observed in A. gephyra extracts. However, heterologous expression of each synthase in Escherichia coli provided detectible quantities of 3 AHL signals including 2 known AHLs, C8-AHL and C9-AHL. These results suggest that A. gephyra AHL production is dormant during axenic cultivation. The functional, orphaned AHL synthase, AgpI, is unique to A. gephyra, and its utility to the predatory myxobacterium remains unknown.
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2
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Moura-Alves P, Puyskens A, Stinn A, Klemm M, Guhlich-Bornhof U, Dorhoi A, Furkert J, Kreuchwig A, Protze J, Lozza L, Pei G, Saikali P, Perdomo C, Mollenkopf HJ, Hurwitz R, Kirschhoefer F, Brenner-Weiss G, Weiner J, Oschkinat H, Kolbe M, Krause G, Kaufmann SHE. Host monitoring of quorum sensing during Pseudomonas aeruginosa infection. Science 2020; 366:366/6472/eaaw1629. [PMID: 31857448 DOI: 10.1126/science.aaw1629] [Citation(s) in RCA: 79] [Impact Index Per Article: 19.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2018] [Revised: 07/25/2019] [Accepted: 11/13/2019] [Indexed: 01/01/2023]
Abstract
Pseudomonas aeruginosa rapidly adapts to altered conditions by quorum sensing (QS), a communication system that it uses to collectively modify its behavior through the production, release, and detection of signaling molecules. QS molecules can also be sensed by hosts, although the respective receptors and signaling pathways are poorly understood. We describe a pattern of regulation in the host by the aryl hydrocarbon receptor (AhR) that is critically dependent on qualitative and quantitative sensing of P. aeruginosa quorum. QS molecules bind to AhR and distinctly modulate its activity. This is mirrored upon infection with P. aeruginosa collected from diverse growth stages and with QS mutants. We propose that by spying on bacterial quorum, AhR acts as a major sensor of infection dynamics, capable of orchestrating host defense according to the status quo of infection.
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Affiliation(s)
- Pedro Moura-Alves
- Department of Immunology, Max Planck Institute for Infection Biology, 10117 Berlin, Germany. .,Ludwig Institute for Cancer Research, Nuffield Department of Clinical Medicine, University of Oxford, Oxford OX3 7DQ, UK
| | - Andreas Puyskens
- Department of Immunology, Max Planck Institute for Infection Biology, 10117 Berlin, Germany
| | - Anne Stinn
- Department of Immunology, Max Planck Institute for Infection Biology, 10117 Berlin, Germany.,Structural Systems Biology, Max Planck Institute for Infection Biology, 10117 Berlin, Germany.,Department of Structural Infection Biology, Centre for Structural Systems Biology, Helmholtz Centre for Infection Research (HZI), 22607 Hamburg, Germany.,Faculty of Mathematics, Informatics and Natural Sciences, University of Hamburg, 20148 Hamburg, Germany
| | - Marion Klemm
- Department of Immunology, Max Planck Institute for Infection Biology, 10117 Berlin, Germany
| | - Ute Guhlich-Bornhof
- Department of Immunology, Max Planck Institute for Infection Biology, 10117 Berlin, Germany
| | - Anca Dorhoi
- Department of Immunology, Max Planck Institute for Infection Biology, 10117 Berlin, Germany.,Institute of Immunology, Friedrich-Loeffler Institut, Greifswald-Insel Riems, Germany.,Faculty of Mathematics and Natural Sciences, University of Greifswald, Greifswald, Germany
| | - Jens Furkert
- Leibniz-Forschungsinstitut für Molekulare Pharmakologie (FMP), 13125 Berlin, Germany
| | - Annika Kreuchwig
- Leibniz-Forschungsinstitut für Molekulare Pharmakologie (FMP), 13125 Berlin, Germany
| | - Jonas Protze
- Leibniz-Forschungsinstitut für Molekulare Pharmakologie (FMP), 13125 Berlin, Germany
| | - Laura Lozza
- Department of Immunology, Max Planck Institute for Infection Biology, 10117 Berlin, Germany.,Epiontis GmbH-Precision for Medicine, 12489 Berlin, Germany
| | - Gang Pei
- Department of Immunology, Max Planck Institute for Infection Biology, 10117 Berlin, Germany
| | - Philippe Saikali
- Department of Immunology, Max Planck Institute for Infection Biology, 10117 Berlin, Germany
| | - Carolina Perdomo
- Department of Immunology, Max Planck Institute for Infection Biology, 10117 Berlin, Germany
| | - Hans J Mollenkopf
- Microarray Core Facility, Max Planck Institute for Infection Biology, Department of Immunology, 10117 Berlin, Germany
| | - Robert Hurwitz
- Protein Purification Core Facility, Max Planck Institute for Infection Biology, 10117 Berlin, Germany
| | - Frank Kirschhoefer
- Institute of Functional Interfaces, Karlsruhe Institute of Technology, Karlsruhe, Germany
| | - Gerald Brenner-Weiss
- Protein Purification Core Facility, Max Planck Institute for Infection Biology, 10117 Berlin, Germany
| | - January Weiner
- Department of Immunology, Max Planck Institute for Infection Biology, 10117 Berlin, Germany
| | - Hartmut Oschkinat
- Leibniz-Forschungsinstitut für Molekulare Pharmakologie (FMP), 13125 Berlin, Germany
| | - Michael Kolbe
- Structural Systems Biology, Max Planck Institute for Infection Biology, 10117 Berlin, Germany.,Department of Structural Infection Biology, Centre for Structural Systems Biology, Helmholtz Centre for Infection Research (HZI), 22607 Hamburg, Germany.,Faculty of Mathematics, Informatics and Natural Sciences, University of Hamburg, 20148 Hamburg, Germany
| | - Gerd Krause
- Leibniz-Forschungsinstitut für Molekulare Pharmakologie (FMP), 13125 Berlin, Germany
| | - Stefan H E Kaufmann
- Department of Immunology, Max Planck Institute for Infection Biology, 10117 Berlin, Germany. .,Hagler Institute for Advanced Study at Texas A&M University, College Station, TX 77843, USA
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3
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Shin D, Gorgulla C, Boursier ME, Rexrode N, Brown EC, Arthanari H, Blackwell HE, Nagarajan R. N-Acyl Homoserine Lactone Analog Modulators of the Pseudomonas aeruginosa Rhll Quorum Sensing Signal Synthase. ACS Chem Biol 2019; 14:2305-2314. [PMID: 31545595 DOI: 10.1021/acschembio.9b00671] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Virulence in the Gram-negative pathogen Pseudomonas aeruginosa relies in part on the efficient functioning of two LuxI/R dependent quorum sensing (QS) cascades, namely, the LasI/R and RhlI/R systems that generate and respond to N-(3-oxo)-dodecanoyl-l-homoserine lactone and N-butyryl-l-homoserine lactone, respectively. The two acyl homoserine lactone (AHL) synthases, LasI and RhlI, use 3-oxododecanoyl-ACP and butyryl-ACP, respectively, as the acyl-substrates to generate the corresponding autoinducer signals for the bacterium. Although AHL synthases represent excellent targets for developing QS modulators in P. aeruginosa, and in other related bacteria, the identification of potent and signal synthase specific inhibitors has represented a significant technical challenge. In the current study, we sought to test the utility of AHL analogs as potential modulators of an AHL synthase and selected RhlI in P. aeruginosa as an initial target. We systematically varied the chemical functionalities of the AHL headgroup, acyl chain tail, and head-to-tail linkage to construct a small library of signal analogs and evaluated them for RhlI modulatory activity. Although the native N-butyryl-l-homoserine lactone did not inhibit RhlI, we discovered that several of our long-chain, unsubstituted acyl-d-homoserine lactones and acyl-d-homocysteine thiolactones inhibited while a few of the 3-oxoacyl-chain counterparts activated the enzyme. Additional mechanistic investigations with acyl-substrate analogs and docking experiments with AHL analogs revealed two distinct inhibitor and activator binding pockets in the enzyme. This study provides the first evidence of the yet untapped potential of AHL analogs as signal synthase modulators of QS pathways.
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Affiliation(s)
- Daniel Shin
- Department of Chemistry and Biochemistry, Boise State University, 1910 University Dr., Boise, Idaho 83725, United States
| | - Christoph Gorgulla
- Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, 240 Longwood Ave, Boston, Massachusetts 02115, United States
- Department of Physics, Harvard University, 17 Oxford Street, Cambridge, Massachusetts 02138, United States
| | - Michelle E. Boursier
- Department of Chemistry, University of Wisconsin—Madison, 1101 University Ave, Madison, Wisconsin 53706, United States
| | - Neilson Rexrode
- Department of Chemistry and Biochemistry, Boise State University, 1910 University Dr., Boise, Idaho 83725, United States
| | - Eric C. Brown
- Department of Chemistry and Biochemistry, Boise State University, 1910 University Dr., Boise, Idaho 83725, United States
| | - Haribabu Arthanari
- Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, 240 Longwood Ave, Boston, Massachusetts 02115, United States
- Department of Cancer Biology, Dana Farber Cancer Institute, Boston, Massachusetts 02115, United States
| | - Helen E. Blackwell
- Department of Chemistry, University of Wisconsin—Madison, 1101 University Ave, Madison, Wisconsin 53706, United States
| | - Rajesh Nagarajan
- Department of Chemistry and Biochemistry, Boise State University, 1910 University Dr., Boise, Idaho 83725, United States
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4
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Kalia VC, Patel SKS, Kang YC, Lee JK. Quorum sensing inhibitors as antipathogens: biotechnological applications. Biotechnol Adv 2018; 37:68-90. [PMID: 30471318 DOI: 10.1016/j.biotechadv.2018.11.006] [Citation(s) in RCA: 167] [Impact Index Per Article: 27.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2018] [Revised: 10/19/2018] [Accepted: 11/18/2018] [Indexed: 12/20/2022]
Abstract
The mechanisms through which microbes communicate using signal molecules has inspired a great deal of research. Microbes use this exchange of information, known as quorum sensing (QS), to initiate and perpetuate infectious diseases in eukaryotic organisms, evading the eukaryotic defense system by multiplying and expressing their pathogenicity through QS regulation. The major issue to arise from such networks is increased bacterial resistance to antibiotics, resulting from QS-dependent mediation of the formation of biofilm, the induction of efflux pumps, and the production of antibiotics. QS inhibitors (QSIs) of diverse origins have been shown to act as potential antipathogens. In this review, we focus on the use of QSIs to counter diseases in humans as well as plants and animals of economic importance. We also discuss the challenges encountered in the potential applications of QSIs.
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Affiliation(s)
- Vipin Chandra Kalia
- Department of Chemical Engineering, Konkuk University, Seoul 05029, Republic of Korea.
| | - Sanjay K S Patel
- Department of Chemical Engineering, Konkuk University, Seoul 05029, Republic of Korea
| | - Yun Chan Kang
- Department of Materials Science and Engineering, Korea University, Anam-Dong, Seongbuk-Gu, Seoul 02841, Republic of Korea
| | - Jung-Kul Lee
- Department of Chemical Engineering, Konkuk University, Seoul 05029, Republic of Korea.
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5
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Barbey C, Chane A, Burini JF, Maillot O, Merieau A, Gallique M, Beury-Cirou A, Konto-Ghiorghi Y, Feuilloley M, Gobert V, Latour X. A Rhodococcal Transcriptional Regulatory Mechanism Detects the Common Lactone Ring of AHL Quorum-Sensing Signals and Triggers the Quorum-Quenching Response. Front Microbiol 2018; 9:2800. [PMID: 30524404 PMCID: PMC6262395 DOI: 10.3389/fmicb.2018.02800] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2018] [Accepted: 10/31/2018] [Indexed: 01/08/2023] Open
Abstract
The biocontrol agent Rhodococcus erythropolis disrupts virulence of plant and human Gram-negative pathogens by catabolizing their N-acyl-homoserine lactones. This quorum-quenching activity requires the expression of the qsd (quorum-sensing signal degradation) operon, which encodes the lactonase QsdA and the fatty acyl-CoA ligase QsdC, involved in the catabolism of lactone ring and acyl chain moieties of signaling molecules, respectively. Here, we demonstrate the regulation of qsd operon expression by a TetR-like family repressor, QsdR. This repression was lifted by adding the pathogen quorum signal or by deleting the qsdR gene, resulting in enhanced lactone degrading activity. Using interactomic approaches and transcriptional fusion strategy, the qsd operon derepression was elucidated: it is operated by the binding of the common part of signaling molecules, the homoserine lactone ring, to the effector-receiving domain of QsdR, preventing a physical binding of QsdR to the qsd promoter region. To our knowledge, this is the first evidence revealing quorum signals as inducers of the suitable quorum-quenching pathway, confirming this TetR-like protein as a lactone sensor. This regulatory mechanism designates the qsd operon as encoding a global disrupting pathway for degrading a wide range of signal substrates, allowing a broad spectrum anti-virulence activity mediated by the rhodococcal biocontrol agent. Understanding the regulation mechanisms of qsd operon expression led also to the development of biosensors useful to monitor in situ the presence of exogenous signals and quorum-quenching activity.
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Affiliation(s)
- Corinne Barbey
- Laboratoire de Microbiologie Signaux et Microenvironnement (LMSM EA 4312) - Normandie Université - LMSM, Évreux, France.,Structure Fédérative de Recherche Normandie Végétal 4277 (NORVEGE), Mont-Saint-Aignan, France.,Seeds Innovation Protection Research and Environment, Achicourt, France.,Seeds Innovation Protection Research and Environment, Bretteville du Grand-Caux, France
| | - Andrea Chane
- Laboratoire de Microbiologie Signaux et Microenvironnement (LMSM EA 4312) - Normandie Université - LMSM, Évreux, France.,Structure Fédérative de Recherche Normandie Végétal 4277 (NORVEGE), Mont-Saint-Aignan, France
| | - Jean-François Burini
- Laboratoire de Microbiologie Signaux et Microenvironnement (LMSM EA 4312) - Normandie Université - LMSM, Évreux, France.,Structure Fédérative de Recherche Normandie Végétal 4277 (NORVEGE), Mont-Saint-Aignan, France
| | - Olivier Maillot
- Laboratoire de Microbiologie Signaux et Microenvironnement (LMSM EA 4312) - Normandie Université - LMSM, Évreux, France.,Structure Fédérative de Recherche Normandie Végétal 4277 (NORVEGE), Mont-Saint-Aignan, France
| | - Annabelle Merieau
- Laboratoire de Microbiologie Signaux et Microenvironnement (LMSM EA 4312) - Normandie Université - LMSM, Évreux, France.,Structure Fédérative de Recherche Normandie Végétal 4277 (NORVEGE), Mont-Saint-Aignan, France
| | - Mathias Gallique
- Laboratoire de Microbiologie Signaux et Microenvironnement (LMSM EA 4312) - Normandie Université - LMSM, Évreux, France.,Structure Fédérative de Recherche Normandie Végétal 4277 (NORVEGE), Mont-Saint-Aignan, France
| | - Amélie Beury-Cirou
- Seeds Innovation Protection Research and Environment, Achicourt, France.,Seeds Innovation Protection Research and Environment, Bretteville du Grand-Caux, France.,French Federation of Seed Potato Growers (FN3PT/RD3PT), Paris, France
| | - Yoan Konto-Ghiorghi
- Laboratoire de Microbiologie Signaux et Microenvironnement (LMSM EA 4312) - Normandie Université - LMSM, Évreux, France.,Structure Fédérative de Recherche Normandie Végétal 4277 (NORVEGE), Mont-Saint-Aignan, France
| | - Marc Feuilloley
- Laboratoire de Microbiologie Signaux et Microenvironnement (LMSM EA 4312) - Normandie Université - LMSM, Évreux, France.,Structure Fédérative de Recherche Normandie Végétal 4277 (NORVEGE), Mont-Saint-Aignan, France
| | - Virginie Gobert
- Seeds Innovation Protection Research and Environment, Achicourt, France.,Seeds Innovation Protection Research and Environment, Bretteville du Grand-Caux, France.,French Federation of Seed Potato Growers (FN3PT/RD3PT), Paris, France
| | - Xavier Latour
- Laboratoire de Microbiologie Signaux et Microenvironnement (LMSM EA 4312) - Normandie Université - LMSM, Évreux, France.,Structure Fédérative de Recherche Normandie Végétal 4277 (NORVEGE), Mont-Saint-Aignan, France
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6
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Niemi O, Laine P, Koskinen P, Pasanen M, Pennanen V, Harjunpää H, Nykyri J, Holm L, Paulin L, Auvinen P, Palva ET, Pirhonen M. Genome sequence of the model plant pathogen Pectobacterium carotovorum SCC1. Stand Genomic Sci 2017; 12:87. [PMID: 29276572 PMCID: PMC5738896 DOI: 10.1186/s40793-017-0301-z] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2017] [Accepted: 12/05/2017] [Indexed: 01/01/2023] Open
Abstract
Bacteria of the genus Pectobacterium are economically important plant pathogens that cause soft rot disease on a wide variety of plant species. Here, we report the genome sequence of Pectobacterium carotovorum strain SCC1, a Finnish soft rot model strain isolated from a diseased potato tuber in the early 1980's. The genome of strain SCC1 consists of one circular chromosome of 4,974,798 bp and one circular plasmid of 5524 bp. In total 4451 genes were predicted, of which 4349 are protein coding and 102 are RNA genes.
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Affiliation(s)
- Outi Niemi
- Division of Genetics, Department of Biosciences, University of Helsinki, Helsinki, Finland
- Viikki Plant Science Centre, University of Helsinki, Helsinki, Finland
| | - Pia Laine
- Institute of Biotechnology, University of Helsinki, Helsinki, Finland
| | - Patrik Koskinen
- Division of Genetics, Department of Biosciences, University of Helsinki, Helsinki, Finland
- Institute of Biotechnology, University of Helsinki, Helsinki, Finland
| | - Miia Pasanen
- Plant Pathology, Department of Agricultural Sciences, University of Helsinki, Helsinki, Finland
| | - Ville Pennanen
- Division of Genetics, Department of Biosciences, University of Helsinki, Helsinki, Finland
- Viikki Plant Science Centre, University of Helsinki, Helsinki, Finland
| | - Heidi Harjunpää
- Division of Genetics, Department of Biosciences, University of Helsinki, Helsinki, Finland
- Viikki Plant Science Centre, University of Helsinki, Helsinki, Finland
| | - Johanna Nykyri
- Plant Pathology, Department of Agricultural Sciences, University of Helsinki, Helsinki, Finland
| | - Liisa Holm
- Division of Genetics, Department of Biosciences, University of Helsinki, Helsinki, Finland
- Institute of Biotechnology, University of Helsinki, Helsinki, Finland
| | - Lars Paulin
- Institute of Biotechnology, University of Helsinki, Helsinki, Finland
| | - Petri Auvinen
- Institute of Biotechnology, University of Helsinki, Helsinki, Finland
| | - E. Tapio Palva
- Division of Genetics, Department of Biosciences, University of Helsinki, Helsinki, Finland
- Viikki Plant Science Centre, University of Helsinki, Helsinki, Finland
| | - Minna Pirhonen
- Plant Pathology, Department of Agricultural Sciences, University of Helsinki, Helsinki, Finland
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7
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Signal Integration in Quorum Sensing Enables Cross-Species Induction of Virulence in Pectobacterium wasabiae. mBio 2017; 8:mBio.00398-17. [PMID: 28536283 PMCID: PMC5442451 DOI: 10.1128/mbio.00398-17] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Bacterial communities can sense their neighbors, regulating group behaviors in response to cell density and environmental changes. The diversity of signaling networks in a single species has been postulated to allow custom responses to different stimuli; however, little is known about how multiple signals are integrated and the implications of this integration in different ecological contexts. In the plant pathogen Pectobacterium wasabiae (formerly Erwinia carotovora), two signaling networks-the N-acyl homoserine lactone (AHL) quorum-sensing system and the Gac/Rsm signal transduction pathway-control the expression of secreted plant cell wall-degrading enzymes, its major virulence determinants. We show that the AHL system controls the Gac/Rsm system by affecting the expression of the regulatory RNA RsmB. This regulation is mediated by ExpR2, the quorum-sensing receptor that responds to the P. wasabiae cognate AHL but also to AHLs produced by other bacterial species. As a consequence, this level of regulation allows P. wasabiae to bypass the Gac-dependent regulation of RsmB in the presence of exogenous AHLs or AHL-producing bacteria. We provide in vivo evidence that this pivotal role of RsmB in signal transduction is important for the ability of P. wasabiae to induce virulence in response to other AHL-producing bacteria in multispecies plant lesions. Our results suggest that the signaling architecture in P. wasabiae was coopted to prime the bacteria to eavesdrop on other bacteria and quickly join the efforts of other species, which are already exploiting host resources.IMPORTANCE Quorum-sensing mechanisms enable bacteria to communicate through small signal molecules and coordinate group behaviors. Often, bacteria have various quorum-sensing receptors and integrate information with other signal transduction pathways, presumably allowing them to respond to different ecological contexts. The plant pathogen Pectobacterium wasabiae has two N-acyl homoserine lactone receptors with apparently the same regulatory functions. Our work revealed that the receptor with the broadest signal specificity is also responsible for establishing the link between the main signaling pathways regulating virulence in P. wasabiae This link is essential to provide P. wasabiae with the ability to induce virulence earlier in response to higher densities of other bacterial species. We further present in vivo evidence that this novel regulatory link enables P. wasabiae to join related bacteria in the effort to degrade host tissue in multispecies plant lesions. Our work provides support for the hypothesis that interspecies interactions are among the major factors influencing the network architectures observed in bacterial quorum-sensing pathways.
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8
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Ruer S, Pinotsis N, Steadman D, Waksman G, Remaut H. Virulence-targeted Antibacterials: Concept, Promise, and Susceptibility to Resistance Mechanisms. Chem Biol Drug Des 2015; 86:379-99. [DOI: 10.1111/cbdd.12517] [Citation(s) in RCA: 59] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2014] [Revised: 12/23/2014] [Accepted: 01/06/2015] [Indexed: 12/25/2022]
Affiliation(s)
- Ségolène Ruer
- Structural and Molecular Microbiology; Structural Biology Research Center; VIB; Pleinlaan 2 Brussels 1050 Belgium
- Structural Biology Brussels; Vrije Universiteit Brussel; Pleinlaan 2 Brussels 1050 Belgium
| | - Nikos Pinotsis
- Institute of Structural and Molecular Biology (ISMB); UCL and Birkbeck College; London WC1E 7HX UK
| | - David Steadman
- Wolfson Institute for Biomedical Research (WIBR); UCL; London WC1E 6BT UK
| | - Gabriel Waksman
- Institute of Structural and Molecular Biology (ISMB); UCL and Birkbeck College; London WC1E 7HX UK
| | - Han Remaut
- Structural and Molecular Microbiology; Structural Biology Research Center; VIB; Pleinlaan 2 Brussels 1050 Belgium
- Structural Biology Brussels; Vrije Universiteit Brussel; Pleinlaan 2 Brussels 1050 Belgium
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9
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Christensen QH, Brecht RM, Dudekula D, Greenberg EP, Nagarajan R. Evolution of acyl-substrate recognition by a family of acyl-homoserine lactone synthases. PLoS One 2014; 9:e112464. [PMID: 25401334 PMCID: PMC4234381 DOI: 10.1371/journal.pone.0112464] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2014] [Accepted: 10/06/2014] [Indexed: 11/23/2022] Open
Abstract
Members of the LuxI protein family catalyze synthesis of acyl-homoserine lactone (acyl-HSL) quorum sensing signals from S-adenosyl-L-methionine and an acyl thioester. Some LuxI family members prefer acyl-CoA, and others prefer acyl-acyl carrier protein (ACP) as the acyl-thioester substrate. We sought to understand the evolutionary history and mechanisms mediating this substrate preference. Our phylogenetic and motif analysis of the LuxI acyl-HSL synthase family indicates that the acyl-CoA-utilizing enzymes evolved from an acyl-ACP-utilizing ancestor. To further understand how acyl-ACPs and acyl-CoAs are recognized by acyl-HSL synthases we studied BmaI1, an octanoyl-ACP-dependent LuxI family member from Burkholderia mallei, and BjaI, an isovaleryl-CoA-dependent LuxI family member from Bradyrhizobium japonicum. We synthesized thioether analogs of their thioester acyl-substrates to probe recognition of the acyl-phosphopantetheine moiety common to both acyl-ACP and acyl-CoA substrates. The kinetics of catalysis and inhibition of these enzymes indicate that they recognize the acyl-phosphopantetheine moiety and they recognize non-preferred substrates with this moiety. We find that CoA substrate utilization arose through exaptation of acyl-phosphopantetheine recognition in this enzyme family.
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Affiliation(s)
- Quin H. Christensen
- Department of Microbiology, University of Washington, Seattle, Washington, United States of America
| | - Ryan M. Brecht
- Department of Chemistry and Biochemistry, Boise State University, Boise, Idaho, United States of America
| | - Dastagiri Dudekula
- Department of Chemistry and Biochemistry, Boise State University, Boise, Idaho, United States of America
| | - E. Peter Greenberg
- Department of Microbiology, University of Washington, Seattle, Washington, United States of America
| | - Rajesh Nagarajan
- Department of Chemistry and Biochemistry, Boise State University, Boise, Idaho, United States of America
- * E-mail:
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10
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Montebello AN, Brecht RM, Turner RD, Ghali M, Pu X, Nagarajan R. Acyl-ACP substrate recognition in Burkholderia mallei BmaI1 acyl-homoserine lactone synthase. Biochemistry 2014; 53:6231-42. [PMID: 25215658 PMCID: PMC4188261 DOI: 10.1021/bi5009529] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The acyl-homoserine lactone (AHL) autoinducer mediated quorum sensing regulates virulence in several pathogenic bacteria. The hallmark of an efficient quorum sensing system relies on the tight specificity in the signal generated by each bacterium. Since AHL signal specificity is derived from the acyl-chain of the acyl-ACP (ACP = acyl carrier protein) substrate, AHL synthase enzymes must recognize and react with the native acyl-ACP with high catalytic efficiency while keeping reaction rates with non-native acyl-ACPs low. The mechanism of acyl-ACP substrate recognition in these enzymes, however, remains elusive. In this study, we investigated differences in catalytic efficiencies for shorter and longer chain acyl-ACP substrates reacting with an octanoyl-homoserine lactone synthase Burkholderia mallei BmaI1. With the exception of two-carbon shorter hexanoyl-ACP, the catalytic efficiencies of butyryl-ACP, decanoyl-ACP, and octanoyl-CoA reacting with BmaI1 decreased by greater than 20-fold compared to the native octanoyl-ACP substrate. Furthermore, we also noticed kinetic cooperativity when BmaI1 reacted with non-native acyl-donor substrates. Our kinetic data suggest that non-native acyl-ACP substrates are unable to form a stable and productive BmaI1·acyl-ACP·SAM ternary complex and are thus effectively discriminated by the enzyme. These results offer insights into the molecular basis of substrate recognition for the BmaI1 enzyme.
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Affiliation(s)
- Aubrey N Montebello
- Department of Chemistry and Biochemistry, Boise State University , 1910 University Drive, Boise, Idaho 83725, United States
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11
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N-acyl homoserine lactone-mediated quorum sensing with special reference to use of quorum quenching bacteria in membrane biofouling control. BIOMED RESEARCH INTERNATIONAL 2014; 2014:162584. [PMID: 25147787 PMCID: PMC4131561 DOI: 10.1155/2014/162584] [Citation(s) in RCA: 57] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/02/2014] [Revised: 07/04/2014] [Accepted: 07/06/2014] [Indexed: 11/17/2022]
Abstract
Membrane biofouling remains a severe problem to be addressed in wastewater treatment systems affecting reactor performance and economy. The finding that many wastewater bacteria rely on N-acyl homoserine lactone-mediated quorum sensing to synchronize their activities essential for biofilm formations; the quenching bacterial quorum sensing suggests a promising approach for control of membrane biofouling. A variety of quorum quenching compounds of both synthetic and natural origin have been identified and found effective in inhibition of membrane biofouling with much less environmental impact than traditional antimicrobials. Work over the past few years has demonstrated that enzymatic quorum quenching mechanisms are widely conserved in several prokaryotic organisms and can be utilized as a potent tool for inhibition of membrane biofouling. Such naturally occurring bacterial quorum quenching mechanisms also play important roles in microbe-microbe interactions and have been used to develop sustainable nonantibiotic antifouling strategies. Advances in membrane fabrication and bacteria entrapment techniques have allowed the implication of such quorum quenching bacteria for better design of membrane bioreactor with improved antibiofouling efficacies. In view of this, the present paper is designed to review and discuss the recent developments in control of membrane biofouling with special emphasis on quorum quenching bacteria that are applied in membrane bioreactors.
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Kalia VC, Wood TK, Kumar P. Evolution of resistance to quorum-sensing inhibitors. MICROBIAL ECOLOGY 2014; 68:13-23. [PMID: 24194099 PMCID: PMC4012018 DOI: 10.1007/s00248-013-0316-y] [Citation(s) in RCA: 89] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/18/2013] [Accepted: 10/14/2013] [Indexed: 05/23/2023]
Abstract
The major cause of mortality and morbidity in human beings is bacterial infection. Bacteria have developed resistance to most of the antibiotics primarily due to large-scale and "indiscriminate" usage. The need is to develop novel mechanisms to treat bacterial infections. The expression of pathogenicity during bacterial infections is mediated by a cell density-dependent phenomenon known as quorum sensing (QS). A wide array of QS systems (QSS) is operative in expressing the virulent behavior of bacterial pathogens. Each QSS may be mediated largely by a few major signals along with others produced in minuscule quantities. Efforts to target signal molecules and their receptors have proved effective in alleviating the virulent behavior of such pathogenic bacteria. These QS inhibitors (QSIs) have been reported to be effective in influencing the pathogenicity without affecting bacterial growth. However, evidence is accumulating that bacteria may develop resistance to QSIs. The big question is whether QSIs will meet the same fate as antibiotics.
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Affiliation(s)
- Vipin C Kalia
- Microbial Biotechnology and Genomics, CSIR-Institute of Genomics and Integrative Biology, Delhi University Campus, Mall Road, Delhi, 110007, India,
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Regulon studies and in planta role of the BraI/R quorum-sensing system in the plant-beneficial Burkholderia cluster. Appl Environ Microbiol 2013; 79:4421-32. [PMID: 23686262 DOI: 10.1128/aem.00635-13] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023] Open
Abstract
The genus Burkholderia is composed of functionally diverse species, and it can be divided into several clusters. One of these, designated the plant-beneficial-environmental (PBE) Burkholderia cluster, is formed by nonpathogenic species, which in most cases have been found to be associated with plants. It was previously established that members of the PBE group share an N-acyl-homoserine lactone (AHL) quorum-sensing (QS) system, designated BraI/R, that produces and responds to 3-oxo-C14-HSL (OC14-HSL). Moreover, some of them also possess a second AHL QS system, designated XenI2/R2, producing and responding to 3-hydroxy-C8-HSL (OHC8-HSL). In the present study, we performed liquid chromatography-electrospray ionization-tandem mass spectrometry (LC-ESI-MS/MS) analysis to determine which AHL molecules are produced by each QS system of this group of bacteria. The results showed that XenI2/R2 is mainly responsible for the production of OHC8-HSL and that the BraI/R system is involved in the production of several different AHLs. This analysis also revealed that Burkholderia phymatum STM815 produces greater amounts of AHLs than the other species tested. Further studies showed that the BraR protein of B. phymatum is more promiscuous than other BraR proteins, responding equally well to several different AHL molecules, even at low concentrations. Transcriptome studies with Burkholderia xenovorans LB400 and B. phymatum STM815 revealed that the BraI/R regulon is species specific, with exopolysaccharide production being the only common phenotype regulated by this system in the PBE cluster. In addition, BraI/R was shown not to be important for plant nodulation by B. phymatum strains or for endophytic colonization and growth promotion of maize by B. phytofirmans PsJN.
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Crépin A, Barbey C, Beury-Cirou A, Hélias V, Taupin L, Reverchon S, Nasser W, Faure D, Dufour A, Orange N, Feuilloley M, Heurlier K, Burini JF, Latour X. Quorum sensing signaling molecules produced by reference and emerging soft-rot bacteria (Dickeya and Pectobacterium spp.). PLoS One 2012; 7:e35176. [PMID: 22539957 PMCID: PMC3335102 DOI: 10.1371/journal.pone.0035176] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2012] [Accepted: 03/09/2012] [Indexed: 12/30/2022] Open
Abstract
Background Several small diffusible molecules are involved in bacterial quorum sensing and virulence. The production of autoinducers-1 and -2, quinolone, indole and γ-amino butyrate signaling molecules was investigated in a set of soft-rot bacteria belonging to six Dickeya or Pectobacterium species including recent or emerging potato isolates. Methodology/Principal Findings Using bacterial biosensors, immunoassay, and chromatographic analysis, we showed that soft-rot bacteria have the common ability to produce transiently during their exponential phase of growth the N-3-oxo-hexanoyl- or the N-3-oxo-octanoyl-l-homoserine lactones and a molecule of the autoinducer-2 family. Dickeya spp. produced in addition the indole-3-acetic acid in tryptophan-rich conditions. All these signaling molecules have been identified for the first time in the novel Dickeya solani species. In contrast, quinolone and γ-amino butyrate signals were not identified and the corresponding synthases are not present in the available genomes of soft-rot bacteria. To determine if the variations of signal production according to growth phase could result from expression modifications of the corresponding synthase gene, the respective mRNA levels were estimated by reverse transcriptase-PCR. While the N-acyl-homoserine lactone production is systematically correlated to the synthase expression, that of the autoinducer-2 follows the expression of an enzyme upstream in the activated methyl cycle and providing its precursor, rather than the expression of its own synthase. Conclusions/Significance Despite sharing the S-adenosylmethionine precursor, no strong link was detected between the production kinetics or metabolic pathways of autoinducers-1 and -2. In contrast, the signaling pathway of autoinducer-2 seems to be switched off by the indole-3-acetic acid pathway under tryptophan control. It therefore appears that the two genera of soft-rot bacteria have similarities but also differences in the mechanisms of communication via the diffusible molecules. Our results designate autoinducer-1 lactones as the main targets for a global biocontrol of soft-rot bacteria communications, including those of emerging isolates.
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Affiliation(s)
- Alexandre Crépin
- Laboratoire de Microbiologie Signaux et Microenvironnement (LMSM) - Normandie Université - Université de Rouen EA 4312 - IUT Evreux, Evreux, France
- SIPRE Comité Nord Station de Recherche et de Création Variétale, Bretteville du Grand Caux, France
| | - Corinne Barbey
- Laboratoire de Microbiologie Signaux et Microenvironnement (LMSM) - Normandie Université - Université de Rouen EA 4312 - IUT Evreux, Evreux, France
| | - Amélie Beury-Cirou
- SIPRE Comité Nord Station de Recherche et de Création Variétale, Bretteville du Grand Caux, France
- Institut des Sciences du Végétal (ISV) UPR 2355 - CNRS, Gif-sur-Yvette, France
| | - Valérie Hélias
- Fédération Nationale des Producteurs de Plants de Pomme de Terre (FN3PT), Paris, France
- Institut de Génétique Environnement et Protection des Plantes (IGEPP) UMR 1349 - INRA, Rennes, France
| | - Laure Taupin
- Laboratoire de Biotechnologie et Chimie Marines (LBCM) - Université de Bretagne-Sud EA 3884, Lorient, France
| | - Sylvie Reverchon
- Microbiologie Adaptation et Pathogénie (MAP) UMR 5240 - Université Claude Bernard Lyon 1-INSA-CNRS-Bayer CropScience, Villeurbanne, France
| | - William Nasser
- Microbiologie Adaptation et Pathogénie (MAP) UMR 5240 - Université Claude Bernard Lyon 1-INSA-CNRS-Bayer CropScience, Villeurbanne, France
| | - Denis Faure
- Institut des Sciences du Végétal (ISV) UPR 2355 - CNRS, Gif-sur-Yvette, France
| | - Alain Dufour
- Laboratoire de Biotechnologie et Chimie Marines (LBCM) - Université de Bretagne-Sud EA 3884, Lorient, France
| | - Nicole Orange
- Laboratoire de Microbiologie Signaux et Microenvironnement (LMSM) - Normandie Université - Université de Rouen EA 4312 - IUT Evreux, Evreux, France
| | - Marc Feuilloley
- Laboratoire de Microbiologie Signaux et Microenvironnement (LMSM) - Normandie Université - Université de Rouen EA 4312 - IUT Evreux, Evreux, France
| | - Karin Heurlier
- Department of Food Sciences, University of Nottingham, Sutton Bonington, United Kingdom
| | - Jean-François Burini
- Laboratoire de Microbiologie Signaux et Microenvironnement (LMSM) - Normandie Université - Université de Rouen EA 4312 - IUT Evreux, Evreux, France
| | - Xavier Latour
- Laboratoire de Microbiologie Signaux et Microenvironnement (LMSM) - Normandie Université - Université de Rouen EA 4312 - IUT Evreux, Evreux, France
- * E-mail:
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Quorum quenching revisited--from signal decays to signalling confusion. SENSORS 2012; 12:4661-96. [PMID: 22666051 PMCID: PMC3355433 DOI: 10.3390/s120404661] [Citation(s) in RCA: 97] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/28/2012] [Revised: 03/23/2012] [Accepted: 03/26/2012] [Indexed: 12/12/2022]
Abstract
In a polymicrobial community, while some bacteria are communicating with neighboring cells (quorum sensing), others are interrupting the communication (quorum quenching), thus creating a constant arms race between intercellular communication. In the past decade, numerous quorum quenching enzymes have been found and initially thought to inactivate the signalling molecules. Though this is widely accepted, the actual roles of these quorum quenching enzymes are now being uncovered. Recent evidence extends the role of quorum quenching to detoxification or metabolism of signalling molecules as food and energy source; this includes “signalling confusion”, a term coined in this paper to refer to the phenomenon of non-destructive modification of signalling molecules. While quorum quenching has been explored as a novel anti-infective therapy targeting, quorum sensing evidence begins to show the development of resistance against quorum quenching.
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Crépin A, Beury-Cirou A, Barbey C, Farmer C, Hélias V, Burini JF, Faure D, Latour X. N-acyl homoserine lactones in diverse Pectobacterium and Dickeya plant pathogens: diversity, abundance, and involvement in virulence. SENSORS 2012; 12:3484-97. [PMID: 22737020 PMCID: PMC3376598 DOI: 10.3390/s120303484] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/15/2012] [Revised: 03/02/2012] [Accepted: 03/06/2012] [Indexed: 11/16/2022]
Abstract
Soft-rot bacteria Pectobacterium and Dickeya use N-acyl homoserine lactones (NAHSLs) as diffusible signals for coordinating quorum sensing communication. The production of NAHSLs was investigated in a set of reference strains and recently-collected isolates, which belong to six species and share the ability to infect the potato host plant. All the pathogens produced different NAHSLs, among which the 3-oxo-hexanoyl- and the 3-oxo-octanoyl-l-homoserine lactones represent at least 90% of total produced NAHSL-amounts. The level of NAHSLs varied from 0.6 to 2 pg/cfu. The involvement of NAHSLs in tuber maceration was investigated by electroporating a quorum quenching vector in each of the bacterial pathogen strains. All the NAHSL-lactonase expressing strains produced a lower amount of NAHSLs as compared to those harboring the empty vector. Moreover, all except Dickeya dadantii 3937 induced a lower level of symptoms in potato tuber assay. Noticeably, aggressiveness appeared to be independent of both nature and amount of produced signals. This work highlights that quorum sensing similarly contributed to virulence in most of the tested Pectobacterium and Dickeya, even the strains had been isolated recently or during the past decades. Thus, these key regulatory-molecules appear as credible targets for developing anti-virulence strategies against these plant pathogens.
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Affiliation(s)
- Alexandre Crépin
- Laboratoire de Microbiologie Signaux et Microenvironnement, Normandie Université, Université de Rouen EA 4312, IUT Evreux, 55 rue Saint-Germain, Evreux F-27000, France; E-Mails: (A.C.); (C.B.); (C.F.); (J.-F.B.)
- SIPRE—Comité Nord, Station de recherche et de création variétale, Bretteville du Grand Caux F-76110, France; E-Mail:
| | - Amélie Beury-Cirou
- SIPRE—Comité Nord, Station de recherche et de création variétale, Bretteville du Grand Caux F-76110, France; E-Mail:
- Institut des Sciences du Végétal, CNRS UPR2355, Avenue de la Terrasse, Gif-sur-Yvette 91198, France; E-Mail:
| | - Corinne Barbey
- Laboratoire de Microbiologie Signaux et Microenvironnement, Normandie Université, Université de Rouen EA 4312, IUT Evreux, 55 rue Saint-Germain, Evreux F-27000, France; E-Mails: (A.C.); (C.B.); (C.F.); (J.-F.B.)
| | - Christine Farmer
- Laboratoire de Microbiologie Signaux et Microenvironnement, Normandie Université, Université de Rouen EA 4312, IUT Evreux, 55 rue Saint-Germain, Evreux F-27000, France; E-Mails: (A.C.); (C.B.); (C.F.); (J.-F.B.)
| | - Valérie Hélias
- FN3PT, Fédération Nationale des Producteurs de Plants de Pomme de Terre, 43-45 rue de Naples, Paris F-75008, France; E-Mail:
- INRA, UMR 1349 IGEPP, Le Rheu Cedex F-35653, France
| | - Jean-François Burini
- Laboratoire de Microbiologie Signaux et Microenvironnement, Normandie Université, Université de Rouen EA 4312, IUT Evreux, 55 rue Saint-Germain, Evreux F-27000, France; E-Mails: (A.C.); (C.B.); (C.F.); (J.-F.B.)
| | - Denis Faure
- Institut des Sciences du Végétal, CNRS UPR2355, Avenue de la Terrasse, Gif-sur-Yvette 91198, France; E-Mail:
| | - Xavier Latour
- Laboratoire de Microbiologie Signaux et Microenvironnement, Normandie Université, Université de Rouen EA 4312, IUT Evreux, 55 rue Saint-Germain, Evreux F-27000, France; E-Mails: (A.C.); (C.B.); (C.F.); (J.-F.B.)
- Author to whom correspondence should be addressed; E-Mail: ; Tel.: +33-2-3229-1549; Fax: +33-2-3229-1550
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Quorum sensing and expression of virulence in pectobacteria. SENSORS 2012; 12:3327-49. [PMID: 22737011 PMCID: PMC3376562 DOI: 10.3390/s120303327] [Citation(s) in RCA: 53] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/16/2012] [Revised: 02/21/2012] [Accepted: 03/02/2012] [Indexed: 01/23/2023]
Abstract
Quorum sensing (QS) is a population density-dependent regulatory mechanism in which gene expression is coupled to the accumulation of a chemical signaling molecule. QS systems are widespread among the plant soft-rotting bacteria. In Pectobacterium carotovorum, at least two QS systems exist being specified by the nature of chemical signals involved. QS in Pectobacterium carotovorum uses N-acylhomoserine lactone (AHL) based, as well as autoinducer-2 (AI-2) dependent signaling systems. This review will address the importance of the QS in production of virulence factors and interaction of QS with other regulatory systems in Pectobacterium carotovorum.
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Fast W, Tipton PA. The enzymes of bacterial census and censorship. Trends Biochem Sci 2011; 37:7-14. [PMID: 22099187 DOI: 10.1016/j.tibs.2011.10.001] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2011] [Revised: 10/04/2011] [Accepted: 10/06/2011] [Indexed: 10/15/2022]
Abstract
N-Acyl-L-homoserine lactones (AHLs) are a major class of quorum-sensing signals used by Gram-negative bacteria to regulate gene expression in a population-dependent manner, thereby enabling group behavior. Enzymes capable of generating and catabolizing AHL signals are of significant interest for the study of microbial ecology and quorum-sensing pathways, for understanding the systems that bacteria have evolved to interact with small-molecule signals, and for their possible use in therapeutic and industrial applications. The recent structural and functional studies reviewed here provide a detailed insight into the chemistry and enzymology of bacterial communication.
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Affiliation(s)
- Walter Fast
- Division of Medicinal Chemistry, College of Pharmacy, University of Texas, Austin, TX 78712, USA.
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19
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Kalia VC, Purohit HJ. Quenching the quorum sensing system: potential antibacterial drug targets. Crit Rev Microbiol 2011; 37:121-40. [PMID: 21271798 DOI: 10.3109/1040841x.2010.532479] [Citation(s) in RCA: 175] [Impact Index Per Article: 13.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
Emergence of antibiotic and multi-drug resistant pathogenic bacteria has created the need for new drugs and drug targets. During pathogenesis bacteria release signals which regulate virulence and pathogenicity related genes. Such bacteria co-ordinate their virulent behaviour in a cell density dependent phenomenon termed as quorum sensing (QS). In contrast, microbes interfere with QS system by quenching the signals, termed quorum quenching (QQ). As a consequence of disrupted QS, pathogens become susceptible to antibiotics and drugs. In this article, the biodiversity of organisms with potential to quench QS signals and the use of QQ molecules as antibacterial drugs have been reviewed.
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Affiliation(s)
- Vipin Chandra Kalia
- Microbial Biotechnology and Genomics, Institute of Genomics and Integrative Biology (IGIB), CSIR, Delhi University Campus, Mall Road, Delhi-110007, India.
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Affiliation(s)
- Mair E A Churchill
- Department of Pharmacology and Program in Structural Biology and Biophysics, The University of Colorado School of Medicine, Aurora, Colorado 80045, USA.
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Abstract
This review describes the chemistry of the bacterial biofilms including the chemistry of their constituents and signalling compounds that mediate or inhibit the formation of biofilms. Systems are described with special emphasis, in which quorum sensing molecules (autoinducers) trigger the formation of biofilms. In the first instance, N-acyl-L-homoserine lactones (AHLs) are the focus of this review, whereas the inter-species signal known as furanosyl borate diester and peptide autoinducers used by Gram-positive bacteria are not discussed in detail. Since the first discovery of an AHL autoinducer from Vibrio fischeri a large and further increasing number of different AHL structures from Gram-negative bacteria have been identified. This review gives a summary of all known AHL autoinducers and producing bacterial species. A few systems are discussed, where biofilm formation is suppressed by enzymatic degradation of AHL molecules or interference of secondary metabolites from other species with the quorum sensing systems of communicating bacteria. Finally, the multi-channel quorum sensing system, the intracellular downstream processing of the signal, and the resulting response of whole populations including biofilm formation are discussed for the Vibrio genus that has been extensively investigated.
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Affiliation(s)
- Jeroen S Dickschat
- Institute of Organic Chemistry, Technical University of Braunschweig, Hagenring 30, Braunschweig, Germany.
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Kambam PKR, Eriksen DT, Lajoie J, Sayut DJ, Sun L. Altering the substrate specificity of RhlI by directed evolution. Chembiochem 2009; 10:553-8. [PMID: 19123197 DOI: 10.1002/cbic.200800636] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
REDUCING VIRULENCE: RhlI catalyzes the synthesis of N-butanoyl homoserine lactone (BHL), with a minor product N-hexanoyl homoserine lactone (HHL). By using directed evolution and a genetic screen, RhlI has been engineered for enhanced production of both BHL and HHL at a similar level. Quorum sensing regulates biofilm formation and virulence factor production in the human opportunistic pathogen Pseudomonas aeruginosa. We used directed evolution to engineer RhlI, an enzyme in the RhlI-RhlR quorum-sensing system of P. aeruginosa, to alter its substrate specificity and gain insight into the molecular mechanisms of quorum sensing. By using a genetic screen, we identified a mutant with improved production of RhlI's two signaling molecules, N-butanoyl- and N-hexanoyl-homoserine lactone (BHL and HHL). In particular, production of BHL has been enhanced by more than two-fold, and the synthesis of HHL has been improved from an undetectable level to a level similar to BHL; this change indicates a significant change in substrate specificity. No significant change in the gene expression level was observed. Sequence alignments suggest that the mutations are most likely to facilitate interactions between the enzyme and the two acylated ACP substrates. This work also demonstrates that the genetic screen/selection should be useful in engineering additional quorum-sensing components.
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Cooley M, Chhabra SR, Williams P. N-Acylhomoserine lactone-mediated quorum sensing: a twist in the tail and a blow for host immunity. ACTA ACUST UNITED AC 2009; 15:1141-7. [PMID: 19022174 DOI: 10.1016/j.chembiol.2008.10.010] [Citation(s) in RCA: 68] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2008] [Revised: 10/17/2008] [Accepted: 10/22/2008] [Indexed: 12/31/2022]
Abstract
Communication through quorum sensing (QS) enables bacterial populations to coordinate their behavior. Recent work on N-acylhomoserine lactone-mediated QS has revealed that some soil bacteria exploit host-derived substrates to generate an alternative N-substituted homoserine lactone. New light has also been shed on the mechanism by which N-(3-oxo-dodecanoyl)-L-homoserine lactone modulates host inflammatory signaling pathways to promote bacterial survival.
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Affiliation(s)
- Margaret Cooley
- Menzies Research Institute and School of Medicine, University of Tasmania, Hobart, TAS 7001, Australia
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25
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Kambam PKR, Sayut DJ, Niu Y, Eriksen DT, Sun L. Directed evolution of LuxI for enhanced OHHL production. Biotechnol Bioeng 2008; 101:263-72. [DOI: 10.1002/bit.21901] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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26
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Sjöblom S, Harjunpää H, Brader G, Palva ET. A novel plant ferredoxin-like protein and the regulator Hor are quorum-sensing targets in the plant pathogen Erwinia carotovora. MOLECULAR PLANT-MICROBE INTERACTIONS : MPMI 2008; 21:967-978. [PMID: 18533837 DOI: 10.1094/mpmi-21-7-0967] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
Quorum sensing (QS), a population-density-sensing mechanism, controls the production of the main virulence determinants, the plant cell-wall-degrading enzymes (PCWDEs) of the soft-rot phytopathogen Erwinia carotovora subsp. carotovora. In this study, we used random transposon mutagenesis with a gusA reporter construct to identify two new QS-controlled genes encoding the regulator Hor and a plant ferredoxin-like protein, FerE. The QS control of the identified genes was executed by the QS regulators ExpR1 and ExpR2 and mediated by the global repressor RsmA. Hor was shown to contribute to bacterial virulence at least partly through its control of PCWDE production. Our results showed that FerE contributes to oxidative stress tolerance and in planta fitness of the bacteria and suggest that QS could be central to control of oxidative stress tolerance. The presence of the FerE protein appears to be rather unique in heterotrophic bacteria and suggests an acquisition of the corresponding gene from plant host by horizontal gene transfer.
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Affiliation(s)
- Solveig Sjöblom
- Viikki Biocenter, Faculty of Biosciences, Department of Biological and Environmental Sciences, Division of Genetics, University of Helsinki, P.O.Box 56, FIN-00014, Helsinki, Finland
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Williams P. Quorum sensing, communication and cross-kingdom signalling in the bacterial world. Microbiology (Reading) 2007; 153:3923-3938. [DOI: 10.1099/mic.0.2007/012856-0] [Citation(s) in RCA: 500] [Impact Index Per Article: 29.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023] Open
Affiliation(s)
- Paul Williams
- Institute of Infection, Immunity and Inflammation, Centre for Biomolecular Sciences, University of Nottingham, Nottingham NG7 2RD, UK
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Latour X, Diallo S, Chevalier S, Morin D, Smadja B, Burini JF, Haras D, Orange N. Thermoregulation of N-acyl homoserine lactone-based quorum sensing in the soft rot bacterium Pectobacterium atrosepticum. Appl Environ Microbiol 2007; 73:4078-81. [PMID: 17468275 PMCID: PMC1932719 DOI: 10.1128/aem.02681-06] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The psychrotolerant bacterium Pectobacterium atrosepticum produces four N-acyl homoserine lactones under a wide range of temperatures. Their thermoregulation differs from that of the exoenzyme production, described as being under quorum-sensing control. A mechanism involved in this thermoregulation consists of controlling N-acyl homoserine lactones synthase production at a transcriptional level.
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Affiliation(s)
- Xavier Latour
- Laboratoire de Microbiologie du Froid - UPRES 2123, Université de Rouen, 55 rue Saint-Germain, F-27000 Evreux, France.
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Li X, Fekete A, Englmann M, Götz C, Rothballer M, Frommberger M, Buddrus K, Fekete J, Cai C, Schröder P, Hartmann A, Chen G, Schmitt-Kopplin P. Development and application of a method for the analysis of N-acylhomoserine lactones by solid-phase extraction and ultra high pressure liquid chromatography. J Chromatogr A 2006; 1134:186-93. [PMID: 17049538 DOI: 10.1016/j.chroma.2006.09.047] [Citation(s) in RCA: 48] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2006] [Revised: 08/09/2006] [Accepted: 09/04/2006] [Indexed: 10/24/2022]
Abstract
A robust method based on solid-phase extraction (SPE) followed by ultra high pressure liquid chromatography (with trade name of Ultra Performance Liquid Chromatography: UPLC; Waters, Milford, MA, USA) is proposed for the determination of five derivatives of N-acylhomoserine lactones (AHLs) that play a biological role as signal molecules of several gram-negative bacteria. Different commercial SPE cartridges were tested for sample extraction, clean-up and preconcentration. Since the sample matrix was a complex growth media, careful optimization of the SPE with respect to washing procedure, elution solvent and sample solvent was necessary. No sample loss was observed when up to 100 mL spiked full media was added onto the cartridge. Applying UPLC for the determination of AHLs, the performance characteristics of the method showed good separation efficiency and high speed. In order to demonstrate the applicability of the method, supernatants with the known AHL producer Burkholderia cepacia LA3 grown in different media were investigated. Additionally, the method was successfully used for the degradation/uptake study of AHLs from a liquid matrix in which barley was grown under controlled condition.
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Affiliation(s)
- Xiaojing Li
- Ministry of Education Key Laboratory of Analysis and Detection Technology for Food Safety, and Department of Chemistry, Fuzhou University, Fuzhou, Fujian 350002, China
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Sjöblom S, Brader G, Koch G, Palva ET. Cooperation of two distinct ExpR regulators controls quorum sensing specificity and virulence in the plant pathogen Erwinia carotovora. Mol Microbiol 2006; 60:1474-89. [PMID: 16796682 DOI: 10.1111/j.1365-2958.2006.05210.x] [Citation(s) in RCA: 68] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Quorum sensing, the population density-dependent regulation mediated by N-acylhomoserine lactones (AHSL), is essential for the control of virulence in the plant pathogen Erwinia carotovora ssp. carotovora (Ecc). In Erwinia carotovora ssp. the AHSL signal with an acyl chain of either 6 or 8 carbons is generated by an AHSL synthase, the expI gene product. This work demonstrates that the AHSL receptor, ExpR1, of Ecc strain SCC3193 has strict specificity for the cognate AHSL 3-oxo-C8-HSL. We have also identified a second AHSL receptor (ExpR2) and demonstrate a novel quorum sensing mechanism, where ExpR2 acts synergistically with the previously described ExpR1 to repress virulence gene expression in Ecc. We show that this repression is released by addition of AHSLs and appears to be largely mediated via the negative regulator RsmA. Additionally we show that ExpR2 has the novel property to sense AHSLs with different acyl chain lengths. The expI expR1 double mutant is able to act in response to a number of different AHSLs, while the expI expR2 double mutant can only respond to the cognate signal of Ecc strain SCC3193. These results suggest that Ecc is able to react both to the cognate AHSL signal and the signals produced by other bacterial species.
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Affiliation(s)
- Solveig Sjöblom
- Viikki Biocenter, Faculty of Biosciences, Department of Biological and Environmental Sciences, Division of Genetics, University of Helsinki, P.O.B. 56, FIN-00014, Helsinki, Finland
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Laasik E, Andresen L, Mäe A. Type II quorum sensing regulates virulence in Erwinia carotovora ssp. carotovora. FEMS Microbiol Lett 2006; 258:227-34. [PMID: 16640578 DOI: 10.1111/j.1574-6968.2006.00222.x] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
Abstract
Quorum sensing is a process by which bacteria communicate using secreted chemical signaling molecules called autoinducers. In this study, the opportunistic plant pathogen Erwinia carotovora ssp. carotovora was observed to secrete type II signaling molecules. A homolog of luxS, the gene required for AI-2 synthesis in Vibrio harveyi, was isolated from the genome of the pathogen. To determine the potential role of AI-2 in virulence, an isogenic luxS- (ECC) mutant was constructed and tested for its ability to cause tissue maceration. The findings reported here demonstrate that the LuxS-dependent signaling affects the progression of disease symptoms during the early stages of infection by modulating the expression of pectinolytic enzymes.
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Affiliation(s)
- Eve Laasik
- Department of Genetics, Institute of Molecular and Cell Biology, Tartu University, Estonian Biocenter, Tartu, Estonia
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Singh MP, Greenstein M. A simple, rapid, sensitive method detecting homoserine lactone (HSL)-related compounds in microbial extracts. J Microbiol Methods 2006; 65:32-7. [PMID: 16019090 DOI: 10.1016/j.mimet.2005.06.003] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2005] [Revised: 06/03/2005] [Accepted: 06/16/2005] [Indexed: 11/19/2022]
Abstract
A simple, rapid, sensitive microtiter plate method detecting N-acyl homoserine lactone (HSL)-related compounds was established using an Agrobacterium tumefaciens strain harboring a traG::lacZ/traR reporter gene responsive to HSLs. This strain did not produce its own HSL, but the traG::lacZ reporter gene was induced only when its transcription activator TraR detected a cognate exogenous HSL. Therefore, the assay was expected to be highly specific for HSL-related compounds. Induction of the reporter gene, leading to production of beta-galactosidase enzyme, was measured by using two different beta-galactosidase substrates, X-gal and Galacton-Star, for colorimetric and chemiluminometric detection, respectively. The screen was validated in both the 96-well and 384-well plate formats, and extracts derived from 696 different microbial isolates, mostly unidentified actinomycetes isolated from diverse locations, were tested. Crude extracts of 81 (11.64%) cultures tested positive for HSL-related compounds, and an additional 34 (4.8%) crude extracts showed a moderate to weak signal for HSLs. Data from the fractionated samples, however, suggested a much higher prevalence of HSL signals in these extracts. Of 144 crude extracts fractionated into 10 individual samples at a 10x concentration, 72 (50%) cultures tested positive for HSLs. Six cultures were active only in the crude extract, 18 were active both in crude and one or more of their fractions, and an additional 48 were active in just one or more of their fractions. This finding may be the first to suggest such a high prevalence of HSL-signals found in nature, and a large number of actinomycetes in our collection appeared to produce HSL-related compounds.
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Affiliation(s)
- Maya Prakash Singh
- Natural Products, Chemical and Screening Sciences, Wyeth Research, Pearl River, NY 10965, USA.
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Gould TA, Herman J, Krank J, Murphy RC, Churchill MEA. Specificity of acyl-homoserine lactone synthases examined by mass spectrometry. J Bacteriol 2006; 188:773-83. [PMID: 16385066 PMCID: PMC1347284 DOI: 10.1128/jb.188.2.773-783.2006] [Citation(s) in RCA: 115] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
Many gram-negative bacteria produce a specific set of N-acyl-L-homoserine-lactone (AHL) signaling molecules for the purpose of quorum sensing, which is a means of regulating coordinated gene expression in a cell-density-dependent manner. AHLs are produced from acylated acyl-carrier protein (acyl-ACP) and S-adenosyl-L-methionine by the AHL synthase enzyme. The appearance of specific AHLs is due in large part to the intrinsic specificity of the enzyme for subsets of acyl-ACP substrates. Structural studies of the Pantoea stewartii enzyme EsaI and AHL-sensitive bioassays revealed that threonine 140 in the acyl chain binding pocket directs the enzyme toward production of 3-oxo-homoserine lactones. Mass spectrometry was used to examine the range of AHL molecular species produced by AHL synthases under a variety of conditions. An AHL selective normal-phase chromatographic purification with addition of a deuterated AHL internal standard was followed by reverse-phase liquid chromatography-tandem mass spectrometry in order to obtain estimates of the relative amounts of different AHLs from biological samples. The AHLs produced by wild-type and engineered EsaI and LasI AHL synthases show that intrinsic specificity and different cellular conditions influence the production of AHLs. The threonine at position 140 in EsaI is important for the preference for 3-oxo-acyl-ACPs, but the role of the equivalent threonine in LasI is less clear. In addition, LasI expressed in Escherichia coli produces a high proportion of unusual AHLs with acyl chains consisting of an odd number of carbons. Furthermore, these studies offer additional methods that will be useful for surveying and quantitating AHLs from different sources.
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Affiliation(s)
- Ty A Gould
- Department of Pharmacology, Program in Biomolecular Structure, The University of Colorado Health Sciences Center, P.O. Box 8511 MS8303, Aurora CO 80045, USA
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Chatterjee A, Cui Y, Hasegawa H, Leigh N, Dixit V, Chatterjee AK. Comparative analysis of two classes of quorum-sensing signaling systems that control production of extracellular proteins and secondary metabolites in Erwinia carotovora subspecies. J Bacteriol 2005; 187:8026-38. [PMID: 16291676 PMCID: PMC1291269 DOI: 10.1128/jb.187.23.8026-8038.2005] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
In Erwinia carotovora subspecies, N-acyl homoserine lactone (AHL) controls the expression of various traits, including extracellular enzyme/protein production and pathogenicity. We report here that E. carotovora subspecies possess two classes of quorum-sensing signaling systems defined by the nature of the major AHL analog produced as well as structural and functional characteristics of AHL synthase (AhlI) and AHL receptor (ExpR). Class I strains represented by E. carotovora subsp. atroseptica strain Eca12 and E. carotovora subsp. carotovora strains EC153 and SCC3193 produce 3-oxo-C8-HL (N-3-oxooctanoyl-l-homoserine lactone) as the major AHL analog as well as low but detectable levels of 3-oxo-C6-HL (N-3-oxohexanoyl-l-homoserine lactone). In contrast, the members of class II (i.e., E. carotovora subsp. betavasculorum strain Ecb168 and E. carotovora subsp. carotovora strains Ecc71 and SCRI193) produce 3-oxo-C6-HL as the major analog. ExpR species of both classes activate rsmA (Rsm, repressor of secondary metabolites) transcription and bind rsmA DNA. Gel mobility shift assays with maltose-binding protein (MBP)-ExpR(71) and MBP-ExpR(153) fusion proteins show that both bind a 20-mer sequence present in rsmA. The two ExpR functions (i.e., expR-mediated activation of rsmA expression and ExpR binding with rsmA DNA) are inhibited by AHL. The AHL effects are remarkably specific in that expR effect of EC153, a strain belonging to class I, is counteracted by 3-oxo-C8-HL but not by 3-oxo-C6-HL. Conversely, the expR effect of Ecc71, a strain belonging to class II, is neutralized by 3-oxo-C6-HL but not by 3-oxo-C8-HL. The AHL responses correlated with expR-mediated inhibition of exoprotein and secondary metabolite production.
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Affiliation(s)
- Asita Chatterjee
- Department of Plant Microbiology & Pathology, University of Missouri, Columbia, MO 65211, USA.
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Farah C, Vera M, Morin D, Haras D, Jerez CA, Guiliani N. Evidence for a functional quorum-sensing type AI-1 system in the extremophilic bacterium Acidithiobacillus ferrooxidans. Appl Environ Microbiol 2005; 71:7033-40. [PMID: 16269739 PMCID: PMC1287726 DOI: 10.1128/aem.71.11.7033-7040.2005] [Citation(s) in RCA: 105] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
Acidithiobacillus ferrooxidans is one of the main acidophilic chemolithotrophic bacteria involved in the bioleaching of metal sulfide ores. The bacterium-mineral interaction requires the development of biofilms, whose formation is regulated in many microorganisms by type AI-1 quorum sensing. Here, we report the existence and characterization of a functional type AI-1 quorum-sensing system in A. ferrooxidans. This microorganism produced mainly acyl-homoserine lactones (AHL) with medium and large acyl chains and different C-3 substitutions, including 3-hydroxy-C8-AHL, 3-hydroxy-C10-AHL, C12-AHL, 3-oxo-C12-AHL, 3-hydroxy-C12-AHL, C14-AHL, 3-oxo-C14-AHL, 3-hydroxy-C14-AHL, and 3-hydroxy-C16-AHL. A quorum-sensing genetic locus that includes two open reading frames, afeI and afeR, which have opposite orientations and code for proteins with high levels of similarity to members of the acyl synthase (I) and transcriptional regulator (R) protein families, respectively, was identified. Overexpression of AfeI in Escherichia coli and the associated synthesis of AHLs confirmed that AfeI is an AHL synthase. As determined by reverse transcription-PCR, the afeI and afeR genes were transcribed in A. ferrooxidans. The transcription levels of the afeI gene were higher in cells grown in sulfur and thiosulfate media than in iron-grown cells. Phosphate starvation induced an increase in the transcription levels of afeI which correlated with an increase in AHL levels. Two afe boxes which could correspond to the AfeR binding sites were identified upstream of the afeI gene. This is the first report of a functional type AI-1 quorum-sensing system in an acidophilic chemolithotrophic microorganism, and our results provide a very interesting opportunity to explore the control and regulation of biofilm formation during the bioleaching process.
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Affiliation(s)
- Carolina Farah
- Laboratorio de Microbiología Molecular y Biotecnología, Departamento de Biología, Facultad de Ciencias, Universidad de Chile, Santiago, Chile
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