151
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Trottmann F, Franke J, Ishida K, García-Altares M, Hertweck C. A Pair of Bacterial Siderophores Releases and Traps an Intercellular Signal Molecule: An Unusual Case of Natural Nitrone Bioconjugation. Angew Chem Int Ed Engl 2018; 58:200-204. [PMID: 30375753 DOI: 10.1002/anie.201811131] [Citation(s) in RCA: 32] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2018] [Indexed: 01/10/2023]
Abstract
In microbial interactions bacteria employ diverse molecules with specific functions, such as sensing the environment, communication with other microbes or hosts, and conferring virulence. Insights into the molecular basis of bacterial communication are thus of high relevance for ecology and medicine. Targeted gene activation and in vitro studies revealed that the cell-to-cell signaling molecule and disease mediator IQS (aeruginaldehyde) of the human pathogen Pseudomonas aeruginosa and related bacteria derives from the siderophore pyochelin. Addition of IQS to bacterial cultures (Burkholderia thailandensis) showed that the signaling molecule is captured by a congener of another siderophore family, malleobactin, to form a nitrone conjugate (malleonitrone) that is active against the IQS-producer. This study uncovers complex communication processes with derailed siderophore functions, a novel nitrone bioconjugation, and a new type of antibiotic against Gram-negative bacteria.
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Affiliation(s)
- Felix Trottmann
- Department of Biomolecular Chemistry, Leibniz Institute, for Natural Product Chemistry and Infection Biology (HKI), Beutenbergstrasse 11a, 07745, Jena, Germany
| | - Jakob Franke
- Department of Biomolecular Chemistry, Leibniz Institute, for Natural Product Chemistry and Infection Biology (HKI), Beutenbergstrasse 11a, 07745, Jena, Germany
| | - Keishi Ishida
- Department of Biomolecular Chemistry, Leibniz Institute, for Natural Product Chemistry and Infection Biology (HKI), Beutenbergstrasse 11a, 07745, Jena, Germany
| | - María García-Altares
- Department of Biomolecular Chemistry, Leibniz Institute, for Natural Product Chemistry and Infection Biology (HKI), Beutenbergstrasse 11a, 07745, Jena, Germany
| | - Christian Hertweck
- Department of Biomolecular Chemistry, Leibniz Institute, for Natural Product Chemistry and Infection Biology (HKI), Beutenbergstrasse 11a, 07745, Jena, Germany.,Natural Product Chemistry, Faculty of Biological Sciences, Friedrich Schiller University Jena, 07743, Jena, Germany
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152
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Shaaban M, Elgaml A, Habib ESE. Biotechnological applications of quorum sensing inhibition as novel therapeutic strategies for multidrug resistant pathogens. Microb Pathog 2018; 127:138-143. [PMID: 30503958 DOI: 10.1016/j.micpath.2018.11.043] [Citation(s) in RCA: 36] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2018] [Revised: 08/25/2018] [Accepted: 11/26/2018] [Indexed: 02/06/2023]
Abstract
High incidence of antibiotic resistance among bacterial clinical isolates necessitates the discovery of new targets for inhibition of microbial pathogenicity, without stimulation of microbial resistance. This could be achieved by targeting virulence determinants, which cause host damage and disease. Many pathogenic bacteria elaborate signaling molecules for cellular communication. This signaling system is named quorum sensing system (QS), and it is contingent on the bacterial population density and mediated by signal molecules called pheromones or autoinducers (AIs). Bacteria utilize QS to regulate activities and behaviors including competence, conjugation, symbiosis, virulence, motility, sporulation, antibiotic production, and biofilm formation. Hence, targeting bacterial communicating signals and suppression of QS exhibit a fundamental approach for competing microbial communication. In this review, we illustrate the common up to date approaches to utilize QS circuits in pathogenic bacteria, including Vibrio fischeri, Pseudomonas aeruginosa, Escherichia coli and Acinetobacter baumannii, as novel therapeutic targets.
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Affiliation(s)
- Mona Shaaban
- Department of Pharmaceutics and Pharmaceutical Technology, College of Pharmacy, Taibah University, Al Madinah Al Munawwarah, 30078, Saudi Arabia; Department of Microbiology and Immunology, Faculty of Pharmacy, Mansoura University, 35516, Egypt
| | - Abdelaziz Elgaml
- Department of Microbiology and Immunology, Faculty of Pharmacy, Mansoura University, 35516, Egypt; Department of Microbiology, Faculty of Pharmacy, Horus University, New Damietta, 34517, Egypt
| | - El-Sayed E Habib
- Department of Pharmaceutics and Pharmaceutical Technology, College of Pharmacy, Taibah University, Al Madinah Al Munawwarah, 30078, Saudi Arabia; Department of Microbiology and Immunology, Faculty of Pharmacy, Mansoura University, 35516, Egypt.
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153
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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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154
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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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155
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Murugayah SA, Warring SL, Gerth ML. Optimisation of a high-throughput fluorescamine assay for detection of N-acyl-l-homoserine lactone acylase activity. Anal Biochem 2018; 566:10-12. [PMID: 30391461 DOI: 10.1016/j.ab.2018.10.029] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2018] [Revised: 10/17/2018] [Accepted: 10/29/2018] [Indexed: 10/27/2022]
Abstract
N-acyl-l-homoserine lactone (AHL) acylases are a well-known group of enzymes that disrupt quorum sensing in Gram-negative bacteria by degrading AHL signalling molecules. This degradation of signalling molecules (termed 'quorum quenching') has potential uses in the prevention or reduction of biofilm formation and/or bacterial infections. Therefore, there is a great deal of interest in the identification and characterisation of quorum quenching enzymes. Here, we present an optimised fluorescamine-based assay for the detection of AHL acylase activity and demonstrate it can be used in a high-throughput screening format.
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Affiliation(s)
- Shereen A Murugayah
- Department of Biochemistry, University of Otago, Dunedin, 9054, New Zealand; Maurice Wilkins Centre for Molecular Biodiscovery, New Zealand
| | - Suzanne L Warring
- Department of Biochemistry, University of Otago, Dunedin, 9054, New Zealand
| | - Monica L Gerth
- Department of Biochemistry, University of Otago, Dunedin, 9054, New Zealand; Maurice Wilkins Centre for Molecular Biodiscovery, New Zealand.
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156
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Recent developments in biofouling control in membrane bioreactors for domestic wastewater treatment. Sep Purif Technol 2018. [DOI: 10.1016/j.seppur.2018.06.004] [Citation(s) in RCA: 100] [Impact Index Per Article: 16.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
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157
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Gupta P, Gupta S, Sharma M, Kumar N, Pruthi V, Poluri KM. Effectiveness of Phytoactive Molecules on Transcriptional Expression, Biofilm Matrix, and Cell Wall Components of Candida glabrata and Its Clinical Isolates. ACS OMEGA 2018; 3:12201-12214. [PMID: 31459295 PMCID: PMC6645245 DOI: 10.1021/acsomega.8b01856] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/01/2018] [Accepted: 09/14/2018] [Indexed: 05/20/2023]
Abstract
Toxicity challenges by antifungal arsenals and emergence of multidrug resistance scenario has posed a serious threat to global community. To cope up with this alarming situation, phytoactive molecules are richest, safest, and most effective source of broad spectrum antimicrobial compounds. In the present investigation, six phytoactive molecules [cinnamaldehyde (CIN), epigallocatechin, vanillin, eugenol (EUG), furanone, and epigallocatechin gallate] were studied against Candida glabrata and its clinical isolates. Among these, CIN and EUG which are active components of cinnamon and clove essential oils, respectively, exhibited maximum inhibition against planktonic growth of C. glabrata at a concentration of 64 and 128 μg mL-1, respectively. These two molecules effectively inhibited and eradicated approximately 80% biofilm of C. glabrata and its clinical isolates from biomaterials. CIN and EUG increased reactive oxygen species generation, cell lysis, and ergosterol content in plasma membrane and reduced virulence attributes (phospholipase and proteinase) as well as catalase activity of C. glabrata cells. Reduction of mitochondrial membrane potential with increased release of cytochrome c from mitochondria to cytosol indicated initiation of early apoptosis in CIN- and EUG-treated C. glabrata cells. Transcriptional analysis showed that multidrug transporter (CDR1) and ergosterol biosynthesis genes were downregulated in the presence of CIN, while getting upregulated in EUG-treated cells. Interestingly, genes such as 1,3-β-glucan synthase (FKS1), GPI-anchored protein (KRE1), and sterol importer (AUS1) were downregulated upon treatment of CIN/EUG. These results provided molecular-level insights about the antifungal mechanism of CIN and EUG against C. glabrata including its resistant clinical isolate. The current data established that CIN and EUG can be potentially formulated in new antifungal strategies.
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Affiliation(s)
- Payal Gupta
- Department
of Biotechnology, Indian Institute of Technology
Roorkee, Roorkee 247667, Uttarakhand, India
| | - Sonam Gupta
- Department
of Biotechnology, Indian Institute of Technology
Roorkee, Roorkee 247667, Uttarakhand, India
| | - Meenakshi Sharma
- Department
of Biotechnology, Indian Institute of Technology
Roorkee, Roorkee 247667, Uttarakhand, India
| | - Navin Kumar
- Department
of Biotechnology, Graphic Era Deemed to
be University, Dehradun 248002, Uttarakhand, India
| | - Vikas Pruthi
- Department
of Biotechnology, Indian Institute of Technology
Roorkee, Roorkee 247667, Uttarakhand, India
| | - Krishna Mohan Poluri
- Department
of Biotechnology, Indian Institute of Technology
Roorkee, Roorkee 247667, Uttarakhand, India
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158
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Nahar S, Mizan MFR, Ha AJW, Ha SD. Advances and Future Prospects of Enzyme-Based Biofilm Prevention Approaches in the Food Industry. Compr Rev Food Sci Food Saf 2018; 17:1484-1502. [DOI: 10.1111/1541-4337.12382] [Citation(s) in RCA: 68] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2018] [Revised: 06/22/2018] [Accepted: 06/27/2018] [Indexed: 12/21/2022]
Affiliation(s)
- Shamsun Nahar
- Dept. of Food Science and Technology; Chung-Ang Univ.; Anseong Gyeonggi-Do 456-756 Republic of Korea
| | | | - Angela Jie-won Ha
- Dept. of Food Science and Technology; Chung-Ang Univ.; Anseong Gyeonggi-Do 456-756 Republic of Korea
| | - Sang-Do Ha
- Dept. of Food Science and Technology; Chung-Ang Univ.; Anseong Gyeonggi-Do 456-756 Republic of Korea
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159
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Bergonzi C, Schwab M, Naik T, Daudé D, Chabrière E, Elias M. Structural and Biochemical Characterization of AaL, a Quorum Quenching Lactonase with Unusual Kinetic Properties. Sci Rep 2018; 8:11262. [PMID: 30050039 PMCID: PMC6062542 DOI: 10.1038/s41598-018-28988-5] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2018] [Accepted: 06/29/2018] [Indexed: 11/10/2022] Open
Abstract
Quorum quenching lactonases are enzymes that are capable of disrupting bacterial signaling based on acyl homoserine lactones (AHL) via their enzymatic degradation. In particular, lactonases have therefore been demonstrated to inhibit bacterial behaviors that depend on these chemicals, such as the formation of biofilms or the expression of virulence factors. Here we characterized biochemically and structurally a novel representative from the metallo-β-lactamase superfamily, named AaL that was isolated from the thermoacidophilic bacterium Alicyclobacillus acidoterrestris. AaL is a potent quorum quenching enzyme as demonstrated by its ability to inhibit the biofilm formation of Acinetobacter baumannii. Kinetic studies demonstrate that AaL is both a proficient and a broad spectrum enzyme, being capable of hydrolyzing a wide range of lactones with high rates (kcat/KM > 105 M-1.s-1). Additionally, AaL exhibits unusually low KM values, ranging from 10 to 80 µM. Analysis of AaL structures bound to phosphate, glycerol, and C6-AHL reveals a unique hydrophobic patch (W26, F87 and I237), involved in substrate binding, possibly accounting for the enzyme's high specificity. Identifying the specificity determinants will aid the development of highly specific quorum quenching enzymes as potential therapeutics.
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Affiliation(s)
- Celine Bergonzi
- Biochemistry, Molecular Biology & Biophysics Dpt and BioTechnology Institute, University of Minnesota, Saint Paul, Minnesota, 55108, USA
| | - Michael Schwab
- Biochemistry, Molecular Biology & Biophysics Dpt and BioTechnology Institute, University of Minnesota, Saint Paul, Minnesota, 55108, USA
| | - Tanushree Naik
- Biochemistry, Molecular Biology & Biophysics Dpt and BioTechnology Institute, University of Minnesota, Saint Paul, Minnesota, 55108, USA
| | - David Daudé
- Gene&GreenTK, 19-21 Boulevard Jean Moulin, 13005, Marseille, France
| | - Eric Chabrière
- Aix Marseille Univ, IRD, APHM, MEPHI, IHU-Méditerranée Infection, Marseille, France
| | - Mikael Elias
- Biochemistry, Molecular Biology & Biophysics Dpt and BioTechnology Institute, University of Minnesota, Saint Paul, Minnesota, 55108, USA.
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160
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Shastry RP, Dolan SK, Abdelhamid Y, Vittal RR, Welch M. Purification and characterisation of a quorum quenching AHL-lactonase from the endophytic bacterium Enterobacter sp. CS66. FEMS Microbiol Lett 2018; 365:4923023. [PMID: 29518220 PMCID: PMC5905603 DOI: 10.1093/femsle/fny054] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2017] [Accepted: 03/05/2018] [Indexed: 12/11/2022] Open
Abstract
The quorum quenching (QQ) activity of endophytic bacteria associated with medicinal plants was explored. Extracts of the Gram-negative Enterobacter sp. CS66 possessed potent N-acylhomoserine lactone (AHL) hydrolytic activity in vitro. Using degenerate primers, we PCR-amplified an open reading frame (denoted aiiE) from CS66 that was 96% identical to the well-characterised AHL-lactonase AiiA from Bacillus thuringiensis, but only 30% was identical to AHL-lactonases from other Gram-negative species. This confirms that close AiiA homologs can be found in both Gram-positive and Gram-negative bacteria. Purified AiiE exhibited potent AHL-lactonase activity against a broad range of AHLs. Furthermore, aiiE was able to reduce the production of secreted plant cell wall-degrading hydrolytic enzymes when expressed in trans in the economically important plant pathogen, Pectobacterium atrosepticum. Our results indicate the presence of a novel AHL-lactonase in Enterobacter sp. CS66 with significant potential as a biocontrol agent.
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Affiliation(s)
- Rajesh Padumane Shastry
- Department of Studies in Microbiology, University of Mysore, Manasagangotri, Mysore 570006, India
- Department of Biochemistry, University of Cambridge, Cambridge CB2 1QW, UK
| | - Stephen K Dolan
- Department of Biochemistry, University of Cambridge, Cambridge CB2 1QW, UK
| | - Yassmin Abdelhamid
- Department of Biochemistry, University of Cambridge, Cambridge CB2 1QW, UK
| | - Ravishankar Rai Vittal
- Department of Studies in Microbiology, University of Mysore, Manasagangotri, Mysore 570006, India
| | - Martin Welch
- Department of Biochemistry, University of Cambridge, Cambridge CB2 1QW, UK
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161
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Kim TH, Lee I, Yeon KM, Kim J. Biocatalytic membrane with acylase stabilized on intact carbon nanotubes for effective antifouling via quorum quenching. J Memb Sci 2018. [DOI: 10.1016/j.memsci.2018.03.020] [Citation(s) in RCA: 27] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
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162
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Utari PD, Setroikromo R, Melgert BN, Quax WJ. PvdQ Quorum Quenching Acylase Attenuates Pseudomonas aeruginosa Virulence in a Mouse Model of Pulmonary Infection. Front Cell Infect Microbiol 2018; 8:119. [PMID: 29755959 PMCID: PMC5932173 DOI: 10.3389/fcimb.2018.00119] [Citation(s) in RCA: 31] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2018] [Accepted: 04/03/2018] [Indexed: 01/24/2023] Open
Abstract
Pseudomonas aeruginosa is the predominant pathogen in pulmonary infections associated with cystic fibrosis. Quorum sensing (QS) systems regulate the production of virulence factors and play an important role in the establishment of successful P. aeruginosa infections. Inhibition of the QS system (termed quorum quenching) renders the bacteria avirulent thus serving as an alternative approach in the development of novel antibiotics. Quorum quenching in Gram negative bacteria can be achieved by preventing the accumulation of N-acyl homoserine lactone (AHL) signaling molecule via enzymatic degradation. Previous work by us has shown that PvdQ acylase hydrolyzes AHL signaling molecules irreversibly, thereby inhibiting QS in P. aeruginosa in vitro and in a Caenorhabditis elegans model of P. aeruginosa infection. The aim of the present study is to assess the therapeutic efficacy of intranasally instilled PvdQ acylase in a mouse model of pulmonary P. aeruginosa infection. First, we evaluated the deposition pattern of intranasally administered fluorochrome-tagged PvdQ (PvdQ-VT) in mice at different stages of pulmonary infection by in vivo imaging studies. Following intranasal instillation, PvdQ-VT could be traced in all lung lobes with 42 ± 7.5% of the delivered dose being deposited at 0 h post-bacterial-infection, and 34 ± 5.2% at 72 h post bacterial-infection. We then treated mice with PvdQ during lethal P. aeruginosa pulmonary infection and that resulted in a 5-fold reduction of lung bacterial load and a prolonged survival of the infected animals with the median survival time of 57 hin comparison to 42 h for the PBS-treated group. In a sublethal P. aeruginosa pulmonary infection, PvdQ treatment resulted in less lung inflammation as well as decrease of CXCL2 and TNF-α levels at 24 h post-bacterial-infection by 15 and 20%, respectively. In conclusion, our study has shown therapeutic efficacy of PvdQ acylase as a quorum quenching agent during P. aeruginosa infection.
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Affiliation(s)
- Putri D. Utari
- Department of Chemical and Pharmaceutical Biology, University of Groningen, Groningen, Netherlands
| | - Rita Setroikromo
- Department of Chemical and Pharmaceutical Biology, University of Groningen, Groningen, Netherlands
| | - Barbro N. Melgert
- Department of Pharmacokinetics, Toxicology and Targeting, University of Groningen, Groningen, Netherlands
| | - Wim J. Quax
- Department of Chemical and Pharmaceutical Biology, University of Groningen, Groningen, Netherlands
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163
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Characterization of AiiK, an AHL lactonase, from Kurthia huakui LAM0618 T and its application in quorum quenching on Pseudomonas aeruginosa PAO1. Sci Rep 2018; 8:6013. [PMID: 29662232 PMCID: PMC5902575 DOI: 10.1038/s41598-018-24507-8] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2017] [Accepted: 04/05/2018] [Indexed: 12/31/2022] Open
Abstract
N-Acyl homoserine lactones (AHLs) act as the key quorum sensing (QS) signal molecules in gram-negative bacteria, which coordinates gene expression and then activates various processes, including biofilm formation and production of virulence factors in some pathogens. Quorum quenching (QQ), which is the inactivation of the signal molecules by means of enzymatic degradation or modification, inhibits the processes of QS rather than killing the pathogens and is a promising antipathogenic strategy to control the bacterial pathogens. In this study, an AHL lactonase gene (named aiiK) was cloned from Kurthia huakuii LAM0618T and the AHL lactonase AiiK was expressed by Escherichia coli. AiiK exhibits a variable substrate spectrum and efficient degradation of the AHL compounds. The enzyme assays demonstrated that AiiK behaves as an AHL lactonase that can hydrolyze the lactone bond of the AHLs. The total hydrolytic efficiency of AiiK for C10-HSL is 3.9 s-1·mM-1. AiiK can also maintain 20% activity after 12 h incubation at 37 °C and demonstrate great resistance to α-chymotrypsin, trypsin, and protease K. Furthermore, AiiK significantly inhibits the biofilm formation and attenuates extracellular proteolytic activity and pyocyanin production of Pseudomonas aeruginosa PAO1, which indicates the potential application of AiiK as a biocontrol agent or an anti-pathogenic drug.
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164
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Mion S, Rémy B, Plener L, Chabrière E, Daudé D. [Prevent bacteria from communicating: Divide to cure]. ANNALES PHARMACEUTIQUES FRANÇAISES 2018; 76:249-264. [PMID: 29598881 DOI: 10.1016/j.pharma.2018.02.004] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2017] [Revised: 02/14/2018] [Accepted: 02/16/2018] [Indexed: 02/07/2023]
Abstract
Quorum Sensing (QS) is a communication system used by numerous bacteria to synchronize their behavior according to the cell density. In this way, bacteria secrete and sense small mediating molecules, called autoinducers (AI), which concentration increases in the environment proportionally to bacterial cell number. QS induces major physiological and phenotypic changes such as virulence induction and biofilm formation. Biofilm represents a physical barrier which shelters bacteria poorly sensitive to antimicrobial treatments and favors the apparition of resistance mechanisms. Disturbing QS is referred to as quorum quenching (QQ). This strategy is used by microorganisms themselves to prevent the development of specific group behaviors. Two strategies are mainly employed: the use of quorum sensing inhibitors (QSI) and of quorum quenching enzymes (QQE) that degrades AI. Many studies have been dedicated to identifying QSI (natural or synthetic) as well as QQE and demonstrating their anti-virulence and anti-biofilm effects on numerous bacterial species. Synergistic effects between QQ and traditional treatments such as antibiotherapy or with reemerging phage therapy have been put forward. The efficiency of numerous QSI and QQE was thereby demonstrated either with in vitro or in vivo animal models leading to the development of medical devices containing QSI and QQE to improve already existing treatments.
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Affiliation(s)
- S Mion
- Aix-Marseille Université, IRD, APHM, MEPHI, IHU-Méditerranée Infection, 19-21, boulevard Jean-Moulin, 13005 Marseille, France
| | - B Rémy
- Aix-Marseille Université, IRD, APHM, MEPHI, IHU-Méditerranée Infection, 19-21, boulevard Jean-Moulin, 13005 Marseille, France; Gene&GreenTK, 19-21, boulevard Jean-Moulin, 13005 Marseille, France
| | - L Plener
- Gene&GreenTK, 19-21, boulevard Jean-Moulin, 13005 Marseille, France
| | - E Chabrière
- Aix-Marseille Université, IRD, APHM, MEPHI, IHU-Méditerranée Infection, 19-21, boulevard Jean-Moulin, 13005 Marseille, France
| | - D Daudé
- Gene&GreenTK, 19-21, boulevard Jean-Moulin, 13005 Marseille, France.
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165
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Rémy B, Mion S, Plener L, Elias M, Chabrière E, Daudé D. Interference in Bacterial Quorum Sensing: A Biopharmaceutical Perspective. Front Pharmacol 2018; 9:203. [PMID: 29563876 PMCID: PMC5845960 DOI: 10.3389/fphar.2018.00203] [Citation(s) in RCA: 171] [Impact Index Per Article: 28.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2017] [Accepted: 02/22/2018] [Indexed: 12/12/2022] Open
Abstract
Numerous bacteria utilize molecular communication systems referred to as quorum sensing (QS) to synchronize the expression of certain genes regulating, among other aspects, the expression of virulence factors and the synthesis of biofilm. To achieve this process, bacteria use signaling molecules, known as autoinducers (AIs), as chemical messengers to share information. Naturally occurring strategies that interfere with bacterial signaling have been extensively studied in recent years, examining their potential to control bacteria. To interfere with QS, bacteria use quorum sensing inhibitors (QSIs) to block the action of AIs and quorum quenching (QQ) enzymes to degrade signaling molecules. Recent studies have shown that these strategies are promising routes to decrease bacterial pathogenicity and decrease biofilms, potentially enhancing bacterial susceptibility to antimicrobial agents including antibiotics and bacteriophages. The efficacy of QSIs and QQ enzymes has been demonstrated in various animal models and are now considered in the development of new medical devices against bacterial infections, including dressings, and catheters for enlarging the therapeutic arsenal against bacteria.
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Affiliation(s)
- Benjamin Rémy
- IRD, APHM, MEPHI, IHU-Méditerranée Infection, Aix Marseille Université, Marseille, France
- Gene&GreenTK, Marseille, France
| | - Sonia Mion
- IRD, APHM, MEPHI, IHU-Méditerranée Infection, Aix Marseille Université, Marseille, France
| | | | - Mikael Elias
- Department of Biochemistry, Molecular Biology and Biophysics, Biotechnology Institute, University of Minnesota, St. Paul, MN, United States
| | - Eric Chabrière
- IRD, APHM, MEPHI, IHU-Méditerranée Infection, Aix Marseille Université, Marseille, France
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166
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Turan NB, Engin GÖ. Quorum Quenching. FUNDAMENTALS OF QUORUM SENSING, ANALYTICAL METHODS AND APPLICATIONS IN MEMBRANE BIOREACTORS 2018. [DOI: 10.1016/bs.coac.2018.02.003] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
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167
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Nature to the natural rescue: Silencing microbial chats. Chem Biol Interact 2017; 280:86-98. [PMID: 29247642 DOI: 10.1016/j.cbi.2017.12.018] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2017] [Revised: 11/22/2017] [Accepted: 12/12/2017] [Indexed: 12/13/2022]
Abstract
Communication is the sole means by which effective networking and co-existence is accomplished amongst living beings. Microbes have their own chit-chats. Science has overheard these microbial gossips and have concluded that these aren't just informal communications, but carefully coordinated signals that plan their effective strategies. Tracking one such signal molecule, N-acyl homoserine lactone (AHL), led to a fundamental understanding to microbial quorum sensing (QS). Furtherance of research sought for ways to cut off communication between these virulent forms, so as to hinder their combinatorial attacks through quorum sensing inhibitors (QSIs). A clear understanding of the inhibitors of these microbial communication systems is vital to destroy their networking and co-working. The current review, consolidates the solutions for QSIs offered from natural sources against these micro components, that are capable of slaughtering even nature's most fit entity-man. The applications of effective out sourcing of this QSI technologies and the need for development are discussed. The importance of silencing this microbial chatter to various aspects of human life and their implications are discussed and elaborated.
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168
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Iorhemen OT, Hamza RA, Tay JH. Membrane fouling control in membrane bioreactors (MBRs) using granular materials. BIORESOURCE TECHNOLOGY 2017; 240:9-24. [PMID: 28314664 DOI: 10.1016/j.biortech.2017.03.005] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/15/2016] [Revised: 02/25/2017] [Accepted: 03/01/2017] [Indexed: 06/06/2023]
Abstract
Membrane fouling is considered the major limitation of membrane bioreactors (MBRs). This paper provides an overview on fouling mitigation in MBRs using granular materials. Adsorbents addition extends filtration period, improves critical flux as well as sludge properties (increased flocs size, reduced soluble EPS, improved dewaterability). However, determination of optimal dosages of adsorbents is needed to balance cost savings from fouling mitigation versus cost of adsorbents and sludge handling. The abrasion from granular media reduces cake layer formation, extends membrane filtration period, increases flux (∼20-30%), and reduces aeration intensity by 50%. Finding appropriate aeration intensity and optimum dose for different media is critical for full-scale application. Granular sludge substantially reduces fouling in MBRs; but, optimal operational conditions for long-term granule stability are required. Quorum quenching (QQ) mitigates biofouling (energy savings ∼27-40%). Cost savings from QQ need assessment against the production and application of QQ approaches.
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Affiliation(s)
- Oliver Terna Iorhemen
- Department of Civil Engineering, University of Calgary, 2500 University Drive NW, Calgary, Alberta T2N 1N4, Canada.
| | - Rania Ahmed Hamza
- Department of Civil Engineering, University of Calgary, 2500 University Drive NW, Calgary, Alberta T2N 1N4, Canada
| | - Joo Hwa Tay
- Department of Civil Engineering, University of Calgary, 2500 University Drive NW, Calgary, Alberta T2N 1N4, Canada
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169
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Frischkorn KR, Rouco M, Van Mooy BAS, Dyhrman ST. Epibionts dominate metabolic functional potential of Trichodesmium colonies from the oligotrophic ocean. THE ISME JOURNAL 2017; 11:2090-2101. [PMID: 28534879 PMCID: PMC5563961 DOI: 10.1038/ismej.2017.74] [Citation(s) in RCA: 45] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/11/2016] [Revised: 02/16/2017] [Accepted: 04/19/2017] [Indexed: 01/21/2023]
Abstract
Trichodesmium is a genus of marine diazotrophic colonial cyanobacteria that exerts a profound influence on global biogeochemistry, by injecting 'new' nitrogen into the low nutrient systems where it occurs. Colonies of Trichodesmium ubiquitously contain a diverse assemblage of epibiotic microorganisms, constituting a microbiome on the Trichodesmium host. Metagenome sequences from Trichodesmium colonies were analyzed along a resource gradient in the western North Atlantic to examine microbiome community structure, functional diversity and metabolic contributions to the holobiont. Here we demonstrate the presence of a core Trichodesmium microbiome that is modulated to suit different ocean regions, and contributes over 10 times the metabolic potential of Trichodesmium to the holobiont. Given the ubiquitous nature of epibionts on colonies, the substantial functional diversity within the microbiome is likely an integral facet of Trichodesmium physiological ecology across the oligotrophic oceans where this biogeochemically significant diazotroph thrives.
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Affiliation(s)
- Kyle R Frischkorn
- Department of Earth and Environmental Sciences and the Lamont-Doherty Earth Observatory, Columbia University, Palisades, NY, USA
| | - Mónica Rouco
- Department of Earth and Environmental Sciences and the Lamont-Doherty Earth Observatory, Columbia University, Palisades, NY, USA
| | - Benjamin A S Van Mooy
- Department of Marine Chemistry and Geochemistry, Woods Hole Oceanographic Institution, Woods Hole, MA, USA
| | - Sonya T Dyhrman
- Department of Earth and Environmental Sciences and the Lamont-Doherty Earth Observatory, Columbia University, Palisades, NY, USA
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170
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Abstract
Antibiotics are undoubtedly a pillar of modern medicine; their discovery in 1929 revolutionized the fight against infectious disease, instigating a worldwide decline in infection-associated mortality. Throughout the 1930s, 1940s, and 1950s the golden age of antibiotic discovery was underway with numerous new classes of antibiotics identified and brought to market. By 1962 all of our currently known families of antibiotics had been discovered, and it was a widely held belief, that humanity had conquered infectious disease. Despite varying bacterial cellular targets, most antibiotics targeted exponentially multiplying bacteria by interfering with integral processes such as peptidoglycan synthesis or ribosomal activity. The very nature of this targeted approach has driven the emergence of antibiotic-resistant bacteria.Methods of antibiotic identification relied solely on scientific observation, and while chemical analogues such as amoxicillin, derived from penicillin, continued to be developed, they retained the same mechanisms of action and hence the same bacterial targets. This article describes and discusses some of the emerging novel targets for antimicrobial treatments, highlighting pivotal research on which our ability to continue to successfully treat bacterial infection relies.
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171
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Utari PD, Vogel J, Quax WJ. Deciphering Physiological Functions of AHL Quorum Quenching Acylases. Front Microbiol 2017; 8:1123. [PMID: 28674525 PMCID: PMC5474475 DOI: 10.3389/fmicb.2017.01123] [Citation(s) in RCA: 43] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2017] [Accepted: 06/01/2017] [Indexed: 11/13/2022] Open
Abstract
N-Acylhomoserine lactone (AHL)-acylase (also known as amidase or amidohydrolase) is a class of enzyme that belongs to the Ntn-hydrolase superfamily. As the name implies, AHL-acylases are capable of hydrolysing AHLs, the most studied signaling molecules for quorum sensing in Gram-negative bacteria. Enzymatic degradation of AHLs can be beneficial in attenuating bacterial virulence, which can be exploited as a novel approach to fight infection of human pathogens, phytopathogens or aquaculture-related contaminations. Numerous acylases from both prokaryotic and eukaryotic sources have been characterized and tested for the interference of quorum sensing-regulated functions. The existence of AHL-acylases in a multitude of organisms from various ecological niches, raises the question of what the physiological roles of AHL-acylases actually are. In this review, we attempt to bring together recent studies to extend our understanding of the biological functions of these enzymes in nature.
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Affiliation(s)
- Putri D Utari
- Chemical and Pharmaceutical Biology Department, University of GroningenGroningen, Netherlands
| | - Jan Vogel
- Chemical and Pharmaceutical Biology Department, University of GroningenGroningen, Netherlands
| | - Wim J Quax
- Chemical and Pharmaceutical Biology Department, University of GroningenGroningen, Netherlands
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172
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Wu X, Kwon SJ, Kim J, Kane RS, Dordick JS. Biocatalytic Nanocomposites for Combating Bacterial Pathogens. Annu Rev Chem Biomol Eng 2017; 8:87-113. [DOI: 10.1146/annurev-chembioeng-060816-101612] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Xia Wu
- Department of Chemical and Biological Engineering, Center for Biotechnology and Interdisciplinary Studies, Rensselaer Polytechnic Institute, Troy, New York 12180
| | - Seok-Joon Kwon
- Department of Chemical and Biological Engineering, Center for Biotechnology and Interdisciplinary Studies, Rensselaer Polytechnic Institute, Troy, New York 12180
| | - Jungbae Kim
- Department of Chemical and Biological Engineering, Korea University, Seoul 02841, Republic of Korea
| | - Ravi S. Kane
- School of Chemical and Biomolecular Engineering, Georgia Institute of Technology, Atlanta, Georgia 30332
| | - Jonathan S. Dordick
- Department of Chemical and Biological Engineering, Center for Biotechnology and Interdisciplinary Studies, Rensselaer Polytechnic Institute, Troy, New York 12180
- Department of Biological Sciences, Rensselaer Polytechnic Institute, Troy, New York 12180
- Department of Biomedical Engineering, Rensselaer Polytechnic Institute, Troy, New York 12180
- Department of Materials Science and Engineering, Rensselaer Polytechnic Institute, Troy, New York 12180
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173
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Brexó RP, Sant'Ana ADS. Microbial interactions during sugar cane must fermentation for bioethanol production: does quorum sensing play a role? Crit Rev Biotechnol 2017; 38:231-244. [PMID: 28574287 DOI: 10.1080/07388551.2017.1332570] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
Abstract
Microbial interactions represent important modulatory role in the dynamics of biological processes. During bioethanol production from sugar cane must, the presence of lactic acid bacteria (LAB) and wild yeasts is inevitable as they originate from the raw material and industrial environment. Increasing the concentration of ethanol, organic acids, and other extracellular metabolites in the fermentation must are revealed as wise strategies for survival by certain microorganisms. Despite this, the co-existence of LAB and yeasts in the fermentation vat and production of compounds such as organic acids and other extracellular metabolites result in reduction in the final yield of the bioethanol production process. In addition to the competition for nutrients, reduction of cellular viability of yeast strain responsible for fermentation, flocculation, biofilm formation, and changes in cell morphology are listed as important factors for reductions in productivity. Although these consequences are scientifically well established, there is still a gap about the physiological and molecular mechanisms governing these interactions. This review aims to discuss the potential occurrence of quorum sensing mechanisms between bacteria (mainly LAB) and yeasts and to highlight how the understanding of such mechanisms can result in very relevant and useful tools to benefit the biofuels industry and other sectors of biotechnology in which bacteria and yeast may co-exist in fermentation processes.
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Affiliation(s)
- Ramon Peres Brexó
- a Department of Food Science, Faculty of Food Engineering , University of Campinas , Campinas , SP , Brazil
| | - Anderson de Souza Sant'Ana
- a Department of Food Science, Faculty of Food Engineering , University of Campinas , Campinas , SP , Brazil
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174
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Zhang Y, Brackman G, Coenye T. Pitfalls associated with evaluating enzymatic quorum quenching activity: the case of MomL and its effect on Pseudomonas aeruginosa and Acinetobacter baumannii biofilms. PeerJ 2017; 5:e3251. [PMID: 28462048 PMCID: PMC5410158 DOI: 10.7717/peerj.3251] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2016] [Accepted: 03/30/2017] [Indexed: 11/20/2022] Open
Abstract
BACKGROUND The enzymatic degradation of quorums sensing (QS) molecules (called quorum quenching, QQ) has been considered as a promising anti-virulence therapy to treat biofilm-related infections and combat antibiotic resistance. The recently-discovered QQ enzyme MomL has been reported to efficiently degrade different N-acyl homoserine lactones (AHLs) of various Gram-negative pathogens. Here we investigated the effect of MomL on biofilms formed by two important nosocomial pathogens, Pseudomonas aeruginosa and Acinetobacter baumannii. METHODS MomL was expressed in E.coli BL21 and purified. The activity of MomL on AHLs with hydroxyl substituent was tested. Biofilms of P. aeruginosa PAO1 and Acinetobacter strains were formed in 96-well microtiter plates. Biofilm formation was evaluated by crystal violet staining, plating and fluorescence microscopy. The effect of MomL on biofilm susceptibility to antibiotics was also tested. We further evaluated MomL in dual-species biofilms formed by P. aeruginosa and A. baumannii, and in biofilms formed in a wound model. The effect of MomL on virulence of A. baumannii was also tested in the Caenorhabditis elegans model. RESULTS MomL reduced biofilm formation and increased biofilm susceptibility to different antibiotics in biofilms of P. aeruginosa PAO1 and A. baumannii LMG 10531 formed in microtiter plates in vitro. However, no significant differences were detected in the dual-species biofilm and in wound model biofilms. In addition, MomL did not affect virulence of A. baumannii in the C. elegans model. Finally, the effect of MomL on biofilm of Acinetobacter strains seems to be strain-dependent. DISCUSSION Our results indicate that although MomL showed a promising anti-biofilm effect against P. aeruginosa and A. baumanii biofilms formed in microtiter plates, the effect on biofilm formation under conditions more likely to mimic the real-life situation was much less pronounced or even absent. Our data indicate that in order to obtain a better picture of potential applicability of QQ enzymes for the treatment of biofilm-related infections, more elaborate model systems need to be used.
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Affiliation(s)
- Yunhui Zhang
- Laboratory of Pharmaceutical Microbiology, Ghent University, Gent, Belgium
| | - Gilles Brackman
- Laboratory of Pharmaceutical Microbiology, Ghent University, Gent, Belgium
| | - Tom Coenye
- Laboratory of Pharmaceutical Microbiology, Ghent University, Gent, Belgium
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175
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Francolini I, Vuotto C, Piozzi A, Donelli G. Antifouling and antimicrobial biomaterials: an overview. APMIS 2017; 125:392-417. [PMID: 28407425 DOI: 10.1111/apm.12675] [Citation(s) in RCA: 161] [Impact Index Per Article: 23.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2016] [Accepted: 01/14/2017] [Indexed: 12/12/2022]
Abstract
The use of implantable medical devices is a common and indispensable part of medical care for both diagnostic and therapeutic purposes. However, as side effect, the implant of medical devices quite often leads to the occurrence of difficult-to-treat infections, as a consequence of the colonization of their abiotic surfaces by biofilm-growing microorganisms increasingly resistant to antimicrobial therapies. A promising strategy to combat device-related infections is based on anti-infective biomaterials that either repel microbes, so they cannot attach to the device surfaces, or kill them in the surrounding areas. In general, such biomaterials are characterized by antifouling coatings, exhibiting low adhesion or even repellent properties towards microorganisms, or antimicrobial coatings, able to kill microbes approaching the surface. In this light, the present overview will address the development in the last two decades of antifouling and antimicrobial biomaterials designed to potentially limit the initial stages of microbial adhesion, as well as the microbial growth and biofilm formation on medical device surfaces.
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Affiliation(s)
| | - Claudia Vuotto
- Microbial Biofilm Laboratory, IRCCS Fondazione Santa Lucia, Rome
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176
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Nasuno E, Suzuki T, Suzuki R, Okano C, Kurokura T, Iimura KI, Kato N. Novel quorum quenching enzymes identified from draft genome of Roseomonas sp. TAS13. GENOMICS DATA 2017; 12:22-23. [PMID: 28275548 PMCID: PMC5328757 DOI: 10.1016/j.gdata.2017.02.001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Received: 01/17/2017] [Revised: 01/28/2017] [Accepted: 02/02/2017] [Indexed: 11/01/2022]
Abstract
Roseomonas sp. strain TAS13 isolated from an activated sludge sample degrades N-acylhomoserine lactones (AHLs) that are widely utilized as a signal in bacterial quorum sensing systems. The draft genome of Roseomonas sp. TAS13 contains 816 contigs (total 5,078,941 bp) which carries 4760 protein-coding genes and 52 tRNA genes (DDBJ/EMBL/GenBank accession numbers BDLP01000001 through BDLP01000816).
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Affiliation(s)
- Eri Nasuno
- Department of Material and Environmental Chemistry, Graduate School of Engineering, Utsunomiya University, 7-1-2 Yoto, Utsunomiya, Tochigi 321-8585, Japan
| | - Tomohiro Suzuki
- Center for Bioscience Research and Education, Utsunomiya University, 350 Mine-machi, Utsunomiya, Tochigi 321-8505, Japan
| | - Ryoko Suzuki
- Department of Material and Environmental Chemistry, Graduate School of Engineering, Utsunomiya University, 7-1-2 Yoto, Utsunomiya, Tochigi 321-8585, Japan
| | - Chigusa Okano
- Creative Department for Innovation, Collaboration Center for Research and Development, Utsunomiya University, 7-1-2 Yoto, Utsunomiya, Tochigi 321-8585, Japan
| | - Takeshi Kurokura
- Faculty of Agriculture, Utsunomiya University, 350 Mine-machi, Utsunomiya, Tochigi 321-8505, Japan
| | - Ken-Ichi Iimura
- Department of Material and Environmental Chemistry, Graduate School of Engineering, Utsunomiya University, 7-1-2 Yoto, Utsunomiya, Tochigi 321-8585, Japan
| | - Norihiro Kato
- Department of Material and Environmental Chemistry, Graduate School of Engineering, Utsunomiya University, 7-1-2 Yoto, Utsunomiya, Tochigi 321-8585, Japan
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177
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Guendouze A, Plener L, Bzdrenga J, Jacquet P, Rémy B, Elias M, Lavigne JP, Daudé D, Chabrière E. Effect of Quorum Quenching Lactonase in Clinical Isolates of Pseudomonas aeruginosa and Comparison with Quorum Sensing Inhibitors. Front Microbiol 2017; 8:227. [PMID: 28261183 PMCID: PMC5306132 DOI: 10.3389/fmicb.2017.00227] [Citation(s) in RCA: 79] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2016] [Accepted: 02/01/2017] [Indexed: 12/19/2022] Open
Abstract
Pseudomonas aeruginosa is a Gram negative pathogenic bacterium involved in many human infections including otitis, keratitis, pneumonia, and diabetic foot ulcers. P. aeruginosa uses a communication system, referred to as quorum sensing (QS), to adopt a group behavior by synchronizing the expression of certain genes. Among the regulated traits, secretion of proteases or siderophores, motility and biofilm formation are mainly involved in the pathogenicity. Many efforts have been dedicated to the development of quorum sensing inhibitors (QSI) and quorum quenching (QQ) agents to disrupt QS. QQ enzymes have been particularly considered as they may act in a catalytic way without entering the cell. Here we focus on the lactonase SsoPox which was previously investigated for its ability to degrade the signaling molecules, acyl-homoserine lactones, in particular on the engineered variant SsoPox-W263I. We highlight the potential of SsoPox-W263I to inhibit the virulence of 51 clinical P. aeruginosa isolates from diabetic foot ulcers by decreasing the secretion of two virulence factors, proteases and pyocyanin, as well as biofilm formation. We further compared the effect of SsoPox-W263I to the comprehensively described QSI, 5-fluorouracil and C-30. We found the lactonase SsoPox-W263I to be significantly more effective than the tested QSI at their respective concentration optimum and to retain its activity after immobilization steps, paving the way for future therapeutic applications.
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Affiliation(s)
- Assia Guendouze
- URMITE, Aix-Marseille Université UM63, CNRS 7278, IRD 198, INSERM 1095 IHU - Méditerranée InfectionMarseille, France; Laboratoire de Biologie Moléculaire et Cellulaire, Université des frères Mentouri ConstantineConstantine, Algérie
| | | | - Janek Bzdrenga
- URMITE, Aix-Marseille Université UM63, CNRS 7278, IRD 198, INSERM 1095 IHU - Méditerranée Infection Marseille, France
| | - Pauline Jacquet
- URMITE, Aix-Marseille Université UM63, CNRS 7278, IRD 198, INSERM 1095 IHU - Méditerranée Infection Marseille, France
| | - Benjamin Rémy
- URMITE, Aix-Marseille Université UM63, CNRS 7278, IRD 198, INSERM 1095 IHU - Méditerranée InfectionMarseille, France; Gene&GreenTKMarseille, France
| | - Mikael Elias
- Department of Biochemistry, Molecular Biology and Biophysics and Biotechnology Institute, University of Minnesota, St. Paul MN, USA
| | - Jean-Philippe Lavigne
- INSERM, U1047, University of Montpellier 1Montpellier, France; Department of Microbiology, Caremeau University HospitalNîmes, France
| | | | - Eric Chabrière
- URMITE, Aix-Marseille Université UM63, CNRS 7278, IRD 198, INSERM 1095 IHU - Méditerranée Infection Marseille, France
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178
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Sarma SJ, Tay JH, Chu A. Finding Knowledge Gaps in Aerobic Granulation Technology. Trends Biotechnol 2017; 35:66-78. [DOI: 10.1016/j.tibtech.2016.07.003] [Citation(s) in RCA: 114] [Impact Index Per Article: 16.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2016] [Revised: 06/29/2016] [Accepted: 07/12/2016] [Indexed: 11/27/2022]
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179
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Quorum Sensing and the Use of Quorum Quenchers as Natural Biocides to Inhibit Sulfate-Reducing Bacteria. Antibiotics (Basel) 2016; 5:antibiotics5040039. [PMID: 27983678 PMCID: PMC5187520 DOI: 10.3390/antibiotics5040039] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2016] [Revised: 11/23/2016] [Accepted: 12/06/2016] [Indexed: 11/17/2022] Open
Abstract
Sulfate-reducing bacteria (SRB) are one of the main protagonist groups of biocorrosion in the seawater environment. Given their principal role in biocorrosion, it remains a crucial task to develop strategies to reduce the abundance of SRBs. Conventional approaches include the use of biocides and antibiotics, which can impose health, safety, and environmental concerns. This review examines an alternative approach to this problem. This is achieved by reviewing the role of quorum sensing (QS) in SRB populations and its impact on the biofilm formation process. Genome databases of SRBs are mined to look for putative QS systems and homologous protein sequences representative of autoinducer receptors or synthases. Subsequently, this review puts forward the potential use of quorum quenchers as natural biocides against SRBs and outlines the potential strategies for the implementation of this approach.
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Tettmann B, Niewerth C, Kirschhöfer F, Neidig A, Dötsch A, Brenner-Weiss G, Fetzner S, Overhage J. Enzyme-Mediated Quenching of the Pseudomonas Quinolone Signal (PQS) Promotes Biofilm Formation of Pseudomonas aeruginosa by Increasing Iron Availability. Front Microbiol 2016; 7:1978. [PMID: 28018312 PMCID: PMC5145850 DOI: 10.3389/fmicb.2016.01978] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2016] [Accepted: 11/25/2016] [Indexed: 11/24/2022] Open
Abstract
The 2-alkyl-3-hydroxy-4(1H)-quinolone 2,4-dioxygenase HodC was previously described to cleave the Pseudomonas quinolone signal, PQS, which is exclusively used in the complex quorum sensing (QS) system of Pseudomonas aeruginosa, an opportunistic pathogen employing QS to regulate virulence and biofilm development. Degradation of PQS by exogenous addition of HodC to planktonic cells of P. aeruginosa attenuated production of virulence factors, and reduced virulence in planta. However, proteolytic cleavage reduced the efficacy of HodC. Here, we identified the secreted protease LasB of P. aeruginosa to be responsible for HodC degradation. In static biofilms of the P. aeruginosa PA14 lasB::Tn mutant, the catalytic activity of HodC led to an increase in viable biomass in newly formed but also in established biofilms, and reduced the expression of genes involved in iron metabolism and siderophore production, such as pvdS, pvdL, pvdA, and pvdQ. This is likely due to an increase in the levels of bioavailable iron by degradation of PQS, which is able to sequester iron from the surrounding environment. Thus, HodC, despite its ability to quench the production of virulence factors, is contraindicated for combating P. aeruginosa biofilms.
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Affiliation(s)
- Beatrix Tettmann
- Karlsruhe Institute of Technology, Institute of Functional Interfaces Karlsruhe, Germany
| | - Christine Niewerth
- Institute for Molecular Microbiology and Biotechnology, University of Münster Münster, Germany
| | - Frank Kirschhöfer
- Karlsruhe Institute of Technology, Institute of Functional Interfaces Karlsruhe, Germany
| | - Anke Neidig
- Karlsruhe Institute of Technology, Institute of Functional Interfaces Karlsruhe, Germany
| | - Andreas Dötsch
- Karlsruhe Institute of Technology, Institute of Functional Interfaces Karlsruhe, Germany
| | - Gerald Brenner-Weiss
- Karlsruhe Institute of Technology, Institute of Functional Interfaces Karlsruhe, Germany
| | - Susanne Fetzner
- Institute for Molecular Microbiology and Biotechnology, University of Münster Münster, Germany
| | - Joerg Overhage
- Karlsruhe Institute of Technology, Institute of Functional Interfaces Karlsruhe, Germany
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181
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Liu X, Cao LC, Fan XJ, Liu YH, Xie W. Engineering of a thermostable esterase Est816 to improve its quorum-quenching activity and the underlying structural basis. Sci Rep 2016; 6:38137. [PMID: 27909291 PMCID: PMC5133562 DOI: 10.1038/srep38137] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2016] [Accepted: 11/04/2016] [Indexed: 12/14/2022] Open
Abstract
N-acyl-homoserine lactones (AHLs) are small diffusible molecules called autoinducers that mediate cell-to-cell communications. Enzymatic degradation of AHLs is a promising bio-control strategy known as quorum-quenching. To improve the quorum-quenching activity of a thermostable esterase Est816, which had been previously cloned, we have engineered the enzyme by random mutagenesis. One of the mutants M2 with double amino acid substitutions (A216V/K238N) showed 3-fold improvement on catalytic efficiency. Based on the crystal structure determined at 2.64 Å, rational design of M2 was conducted, giving rise to the mutant M3 (A216V/K238N/L122A). The kcat/KM value of the mutant M3 is 21.6-fold higher than that of Est816. Furthermore, activity assays demonstrated that M3 reached 99% conversion of 10-μM N-octanoyl-DL-homoserine lactone (C8-HSL) to N-octanoyl- DL-homoserine (C8-Hse) in 20 min, in contrast to the 8 h required by wild type Est816. The dramatic activity enhancement may be attributed to the increased hydrophobic interactions with the lactone ring by the mutation A216V, and the reduced steric clashes between the long side chain of L122 and the aliphatic tail of HSL by the mutation L122A, according to the crystal structure. This study sheds lights on the activity-structure relationship of AHL-lactonases, and may provide useful information in engineering AHL-degrading enzymes.
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Affiliation(s)
- Xiwen Liu
- School of Life Sciences, Sun Yat-sen University, 135 W. Xingang Rd., Guangzhou, Guangdong 510275, P. R. China.,State Key Laboratory for Biocontrol, Sun Yat-sen University, 135 W. Xingang Rd., Guangzhou, Guangdong 510275, P. R. China
| | - Li-Chuang Cao
- School of Life Sciences, Sun Yat-sen University, 135 W. Xingang Rd., Guangzhou, Guangdong 510275, P. R. China.,South China Sea Bio-Resource Exploitation and Utilization Collaborative Innovation Center, Sun Yat-sen University, 135 W. Xingang Rd., Guangzhou 510275, P. R. China
| | - Xin-Jiong Fan
- School of Basic Medical Sciences, Anhui Medical University, 81 Meishan Rd., Hefei, Anhui 230032, P. R, China
| | - Yu-Huan Liu
- School of Life Sciences, Sun Yat-sen University, 135 W. Xingang Rd., Guangzhou, Guangdong 510275, P. R. China.,South China Sea Bio-Resource Exploitation and Utilization Collaborative Innovation Center, Sun Yat-sen University, 135 W. Xingang Rd., Guangzhou 510275, P. R. China
| | - Wei Xie
- School of Life Sciences, Sun Yat-sen University, 135 W. Xingang Rd., Guangzhou, Guangdong 510275, P. R. China.,State Key Laboratory for Biocontrol, Sun Yat-sen University, 135 W. Xingang Rd., Guangzhou, Guangdong 510275, P. R. China
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182
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Patel NM, Moore JD, Blackwell HE, Amador-Noguez D. Identification of Unanticipated and Novel N-Acyl L-Homoserine Lactones (AHLs) Using a Sensitive Non-Targeted LC-MS/MS Method. PLoS One 2016; 11:e0163469. [PMID: 27706219 PMCID: PMC5051804 DOI: 10.1371/journal.pone.0163469] [Citation(s) in RCA: 46] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2016] [Accepted: 09/10/2016] [Indexed: 12/31/2022] Open
Abstract
N-acyl L-homoserine lactones (AHLs) constitute a predominant class of quorum-sensing signaling molecules used by Gram-negative bacteria. Here, we report a sensitive and non-targeted HPLC-MS/MS method based on parallel reaction monitoring (PRM) to identify and quantitate known, unanticipated, and novel AHLs in microbial samples. Using a hybrid quadrupole-high resolution mass analyzer, this method integrates MS scans and all-ion fragmentation MS/MS scans to allow simultaneous detection of AHL parent-ion masses and generation of full mass spectra at high resolution and high mass accuracy in a single chromatographic run. We applied this method to screen for AHL production in a variety of Gram-negative bacteria (i.e. B. cepacia, E. tarda, E. carotovora, E. herbicola, P. stewartii, P. aeruginosa, P. aureofaciens, and R. sphaeroides) and discovered that nearly all of them produce a larger set of AHLs than previously reported. Furthermore, we identified production of an uncommon AHL (i.e. 3-oxo-C7-HL) in E. carotovora and P. stewartii, whose production has only been previously observed within the genera Serratia and Yersinia. Finally, we used our method to quantitate AHL degradation in B. cepacia, E. carotovora, E. herbicola, P. stewartii, P. aeruginosa, P. aureofaciens, the non-AHL producer E. coli, and the Gram-positive bacterium B. subtilis. We found that AHL degradation ability varies widely across these microbes, of which B. subtilis and E. carotovora are the best degraders, and observed that there is a general trend for AHLs containing long acyl chains (≥10 carbons) to be degraded at faster rates than AHLs with short acyl chains (≤6 carbons).
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Affiliation(s)
- Nishaben M. Patel
- Department of Bacteriology, 1550 Linden Dr., University of Wisconsin-Madison, Madison, Wisconsin, United States of America
- Master of Science in Bacteriology Program, University of Wisconsin-Madison, Madison, Wisconsin, United States of America
| | - Joseph D. Moore
- Department of Chemistry, 1101 University Ave., University of Wisconsin-Madison, Madison, Wisconsin, United States of America
| | - Helen E. Blackwell
- Department of Chemistry, 1101 University Ave., University of Wisconsin-Madison, Madison, Wisconsin, United States of America
| | - Daniel Amador-Noguez
- Department of Bacteriology, 1550 Linden Dr., University of Wisconsin-Madison, Madison, Wisconsin, United States of America
- * E-mail:
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183
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Secretory expression of a heterologous protein, Aiio-AIO6BS, in Bacillus subtilis via a non-classical secretion pathway. Biochem Biophys Res Commun 2016; 478:881-6. [DOI: 10.1016/j.bbrc.2016.08.045] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2016] [Accepted: 08/08/2016] [Indexed: 12/27/2022]
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184
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Huang J, Shi Y, Zeng G, Gu Y, Chen G, Shi L, Hu Y, Tang B, Zhou J. Acyl-homoserine lactone-based quorum sensing and quorum quenching hold promise to determine the performance of biological wastewater treatments: An overview. CHEMOSPHERE 2016; 157:137-151. [PMID: 27213243 DOI: 10.1016/j.chemosphere.2016.05.032] [Citation(s) in RCA: 146] [Impact Index Per Article: 18.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/22/2016] [Revised: 04/21/2016] [Accepted: 05/11/2016] [Indexed: 06/05/2023]
Abstract
Quorum sensing (QS) is a communication process between cells, in which bacteria secrete and sense the specific chemicals, and regulate gene expression in response to population density. Quorum quenching (QQ) blocks QS system, and inhibits gene expression mediating bacterial behaviors. Given the extensive research of acyl-homoserine lactone (AHL) signals, existences and effects of AHL-based QS and QQ in biological wastewater treatments are being subject to high concern. This review summarizes AHL structure, synthesis mode, degradation mechanisms, analytical methods, environmental factors, AHL-based QS and QQ mechanisms. The existences and roles of AHL-based QS and QQ in biomembrane processes, activated sludge processes and membrane bioreactors are summarized and discussed, and corresponding exogenous regulation strategy by selective enhancement of AHL-based QS or QQ coexisting in biological wastewater treatments is suggested. Such strategies including the addition of AHL signals, AHL-producing bacteria as well as quorum quenching enzyme or bacteria can effectively improve wastewater treatment performance without killing or limiting bacterial survival and growth. This review will present the theoretical and practical cognition for bacterial AHL-based QS and QQ, suggest the feasibility of exogenous regulation strategies in biological wastewater treatments, and provide useful information to scientists and engineers who work in this field.
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Affiliation(s)
- Jinhui Huang
- College of Environmental Science and Engineering, Hunan University, Changsha, Hunan, 410082, China; Key Laboratory of Environmental Biology and Pollution Control, Hunan University, Ministry of Education, Changsha, Hunan, 410082, China.
| | - Yahui Shi
- College of Environmental Science and Engineering, Hunan University, Changsha, Hunan, 410082, China; Key Laboratory of Environmental Biology and Pollution Control, Hunan University, Ministry of Education, Changsha, Hunan, 410082, China
| | - Guangming Zeng
- College of Environmental Science and Engineering, Hunan University, Changsha, Hunan, 410082, China; Key Laboratory of Environmental Biology and Pollution Control, Hunan University, Ministry of Education, Changsha, Hunan, 410082, China
| | - Yanling Gu
- College of Environmental Science and Engineering, Hunan University, Changsha, Hunan, 410082, China; Key Laboratory of Environmental Biology and Pollution Control, Hunan University, Ministry of Education, Changsha, Hunan, 410082, China
| | - Guiqiu Chen
- College of Environmental Science and Engineering, Hunan University, Changsha, Hunan, 410082, China; Key Laboratory of Environmental Biology and Pollution Control, Hunan University, Ministry of Education, Changsha, Hunan, 410082, China
| | - Lixiu Shi
- College of Environmental Science and Engineering, Hunan University, Changsha, Hunan, 410082, China; Key Laboratory of Environmental Biology and Pollution Control, Hunan University, Ministry of Education, Changsha, Hunan, 410082, China
| | - Yi Hu
- College of Environmental Science and Engineering, Hunan University, Changsha, Hunan, 410082, China; Key Laboratory of Environmental Biology and Pollution Control, Hunan University, Ministry of Education, Changsha, Hunan, 410082, China
| | - Bi Tang
- College of Environmental Science and Engineering, Hunan University, Changsha, Hunan, 410082, China; Key Laboratory of Environmental Biology and Pollution Control, Hunan University, Ministry of Education, Changsha, Hunan, 410082, China
| | - Jianxin Zhou
- College of Environmental Science and Engineering, Hunan University, Changsha, Hunan, 410082, China; Key Laboratory of Environmental Biology and Pollution Control, Hunan University, Ministry of Education, Changsha, Hunan, 410082, China
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185
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Rémy B, Plener L, Elias M, Daudé D, Chabrière E. [Enzymes for disrupting bacterial communication, an alternative to antibiotics?]. ANNALES PHARMACEUTIQUES FRANÇAISES 2016; 74:413-420. [PMID: 27475310 DOI: 10.1016/j.pharma.2016.06.005] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2016] [Revised: 06/20/2016] [Accepted: 06/28/2016] [Indexed: 02/03/2023]
Abstract
Quorum sensing (QS) is used by bacteria to communicate and synchronize their actions according to the cell density. In this way, they produce and secrete in the surrounding environment small molecules dubbed autoinducers (AIs) that regulate the expression of certain genes. The phenotypic traits regulated by QS are diverse and include pathogenicity, biofilm formation or resistance to anti-microbial treatments. The strategy, aiming at disrupting QS, known as quorum quenching (QQ), has emerged to counteract bacterial virulence and involves QS-inhibitors (QSI) or QQ-enzymes degrading AIs. Differently from antibiotics, QQ aims at blocking cell signaling and does not alter bacterial survival. This considerably decreases the selection pressure as compared to bactericide treatments and may reduce the occurrence of resistance mechanisms. QQ-enzymes are particularly appealing as they may disrupt molecular QS-signal without entering the cell and in a catalytic way. This review covers several aspects of QQ-based medical applications and the potential subsequent emergence of resistance is discussed.
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Affiliation(s)
- B Rémy
- IRD 198, Inserm 1095, URMITE, UM63, CNRS 7278, Aix Marseille université, 13385 Marseille cedex 05, France; Gene&GreenTK, faculté de médecine, 27, boulevard Jean-Moulin, 13385 Marseille cedex 5, France
| | - L Plener
- Gene&GreenTK, faculté de médecine, 27, boulevard Jean-Moulin, 13385 Marseille cedex 5, France
| | - M Elias
- Department of Biochemistry, Molecular Biology and Biophysics & Biotechnology Institute, University of Minnesota, 55108 St. Paul, MN, États-Unis
| | - D Daudé
- Gene&GreenTK, faculté de médecine, 27, boulevard Jean-Moulin, 13385 Marseille cedex 5, France.
| | - E Chabrière
- IRD 198, Inserm 1095, URMITE, UM63, CNRS 7278, Aix Marseille université, 13385 Marseille cedex 05, France.
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186
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Weiland-Bräuer N, Kisch MJ, Pinnow N, Liese A, Schmitz RA. Highly Effective Inhibition of Biofilm Formation by the First Metagenome-Derived AI-2 Quenching Enzyme. Front Microbiol 2016; 7:1098. [PMID: 27468282 PMCID: PMC4942472 DOI: 10.3389/fmicb.2016.01098] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2016] [Accepted: 06/30/2016] [Indexed: 11/13/2022] Open
Abstract
Bacterial cell-cell communication (quorum sensing, QS) represents a fundamental process crucial for biofilm formation, pathogenicity, and virulence allowing coordinated, concerted actions of bacteria depending on their cell density. With the widespread appearance of antibiotic-resistance of biofilms, there is an increasing need for novel strategies to control harmful biofilms. One attractive and most likely effective approach is to target bacterial communication systems for novel drug design in biotechnological and medical applications. In this study, metagenomic large-insert libraries were constructed and screened for QS interfering activities (quorum quenching, QQ) using recently established reporter strains. Overall, 142 out of 46,400 metagenomic clones were identified to interfere with acyl-homoserine lactones (AHLs), 13 with autoinducer-2 (AI-2). Five cosmid clones with highest simultaneous interfering activities were further analyzed and the respective open reading frames conferring QQ activities identified. Those showed homologies to bacterial oxidoreductases, proteases, amidases and aminotransferases. Evaluating the ability of the respective purified QQ-proteins to prevent biofilm formation of several model systems demonstrated highest inhibitory effects of QQ-2 using the crystal violet biofilm assay. This was confirmed by heterologous expression of the respective QQ proteins in Klebsiella oxytoca M5a1 and monitoring biofilm formation in a continuous flow cell system. Moreover, QQ-2 chemically immobilized to the glass surface of the flow cell effectively inhibited biofilm formation of K. oxytoca as well as clinical K. pneumoniae isolates derived from patients with urinary tract infections. Indications were obtained by molecular and biochemical characterizations that QQ-2 represents an oxidoreductase most likely reducing the signaling molecules AHL and AI-2 to QS-inactive hydroxy-derivatives. Overall, we propose that the identified novel QQ-2 protein efficiently inhibits AI-2 modulated biofilm formation by modifying the signal molecule; and thus appears particularly attractive for medical and biotechnological applications.
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Affiliation(s)
- Nancy Weiland-Bräuer
- Institute for General Microbiology, Molecular Microbiology, University KielKiel, Germany
| | - Martin J. Kisch
- Institute of Technical Biocatalysis, Technical University HamburgHamburg, Germany
| | - Nicole Pinnow
- Institute for General Microbiology, Molecular Microbiology, University KielKiel, Germany
| | - Andreas Liese
- Institute of Technical Biocatalysis, Technical University HamburgHamburg, Germany
| | - Ruth A. Schmitz
- Institute for General Microbiology, Molecular Microbiology, University KielKiel, Germany
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187
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Grover N, Plaks JG, Summers SR, Chado GR, Schurr MJ, Kaar JL. Acylase-containing polyurethane coatings with anti-biofilm activity. Biotechnol Bioeng 2016; 113:2535-2543. [DOI: 10.1002/bit.26019] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2016] [Revised: 05/19/2016] [Accepted: 05/22/2016] [Indexed: 11/08/2022]
Affiliation(s)
- Navdeep Grover
- Department of Chemical and Biological Engineering; University of Colorado; Boulder Colorado 80309
| | - Joseph G. Plaks
- Department of Chemical and Biological Engineering; University of Colorado; Boulder Colorado 80309
| | - Samantha R. Summers
- Department of Chemical and Biological Engineering; University of Colorado; Boulder Colorado 80309
| | - Garrett R. Chado
- Department of Chemical and Biological Engineering; University of Colorado; Boulder Colorado 80309
| | - Michael J. Schurr
- Department of Immunology and Microbiology; University of Colorado School of Medicine; Aurora Colorado
| | - Joel L. Kaar
- Department of Chemical and Biological Engineering; University of Colorado; Boulder Colorado 80309
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188
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Welsh MA, Blackwell HE. Chemical probes of quorum sensing: from compound development to biological discovery. FEMS Microbiol Rev 2016; 40:774-94. [PMID: 27268906 DOI: 10.1093/femsre/fuw009] [Citation(s) in RCA: 90] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 05/06/2016] [Indexed: 01/20/2023] Open
Abstract
Bacteria can utilize chemical signals to coordinate the expression of group-beneficial behaviors in a method of cell-cell communication called quorum sensing (QS). The discovery that QS controls the production of virulence factors and biofilm formation in many common pathogens has driven an explosion of research aimed at both deepening our fundamental understanding of these regulatory networks and developing chemical agents that can attenuate QS signaling. The inherently chemical nature of QS makes studying these pathways with small molecule tools a complementary approach to traditional microbiology techniques. Indeed, chemical tools are beginning to yield new insights into QS regulation and provide novel strategies to inhibit QS. Here, we review the most recent advances in the development of chemical probes of QS systems in Gram-negative bacteria, with an emphasis on the opportunistic pathogen Pseudomonas aeruginosa We first describe reports of novel small molecule modulators of QS receptors and QS signal synthases. Next, in several case studies, we showcase how chemical tools have been deployed to reveal new knowledge of QS biology and outline lessons for how researchers might best target QS to combat bacterial virulence. To close, we detail the outstanding challenges in the field and suggest strategies to overcome these issues.
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Affiliation(s)
- Michael A Welsh
- Department of Chemistry, University of Wisconsin-Madison, 1101 University Ave., Madison, WI 53706, USA
| | - Helen E Blackwell
- Department of Chemistry, University of Wisconsin-Madison, 1101 University Ave., Madison, WI 53706, USA
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189
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Chu W, McLean RJC. Quorum Signal Inhibitors and Their Potential Use against Fish Diseases. JOURNAL OF AQUATIC ANIMAL HEALTH 2016; 28:91-96. [PMID: 27184419 DOI: 10.1080/08997659.2016.1150907] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
Quorum sensing (QS) is a process of bacterial communication used to control group behaviors, including bioluminescence, virulence factor production, biofilm formation, and biofilm antimicrobial tolerance. Many aquatic bacterial pathogens such as Aeromonas, Vibrio, and Edwardsiella spp. use QS to regulate virulence factor production. The disruption of QS has been shown to be an effective strategy in the competition between higher organisms and bacteria and more recently between bacterial species. For this reason, QS disruption has been proposed as a strategy to prevent bacterial pathogenicity. In this review, we summarize the current literature and illustrate the value of QS inhibitors in controlling virulence production in aquatic bacterial pathogens. This represents a new, nonantibiotic strategy to combat fish diseases. Received August 11, 2015; accepted January 26, 2016.
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Affiliation(s)
- Weihua Chu
- a Department of Microbiology , School of Life Science and Technology, China Pharmaceutical University , Nanjing 210009 , China
| | - Robert J C McLean
- b Department of Biology , Texas State University , 601 University Drive, San Marcos , Texas 78666 , USA
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190
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Valera MJ, Mas A, Streit WR, Mateo E. GqqA, a novel protein in Komagataeibacter europaeus involved in bacterial quorum quenching and cellulose formation. Microb Cell Fact 2016; 15:88. [PMID: 27221658 PMCID: PMC4879726 DOI: 10.1186/s12934-016-0482-y] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2015] [Accepted: 05/03/2016] [Indexed: 01/10/2023] Open
Abstract
Background We report on the functional screening and identification of an active quorum quenching (QQ) gene in the Komagataeibacter europaeus strain CECT 8546, which is a member of the acetic acid bacteria (AAB). Results Using a previously published screening protocol (Schipper et al., in Appl Environ Microbiol 75:224–233, 2009. doi: 10.1128/AEM.01389-08) for QQ genes, we identified a single gene, designated gqqA, that interfered strongly with bacterial quorum sensing (QS) in various reporter strains. It encodes for a 281-amino acid protein with a molecular mass of 30 kDa. Although the GqqA protein is similar to predicted prephenate dehydratases, it does not complement Escherichia coli mutants of the pheA gene, thus indicating a potentially different function. Recombinant GqqA protein attenuated QS-dependent pyocyanin production and swarming motility in the Pseudomonas aeruginosa strain PAO1. Moreover, GqqA quenched the QS response of the Agrobacterium tumefaciens NTL4 and the Chromobacterium violaceum CV026 reporter strains. Interestingly, the addition of recombinant GqqA protein to growing cultures of the Komagataeibacter europaeus strain CECT 8546 altered the cellulose production phenotype of CECT 8546 and other AAB strains. In the presence of GqqA protein, cells were planktonic, and no visible cellulose biofilms formed. The addition of low levels of N-acylhomoserine lactones maintained the biofilm formation phenotype. Conclusions Our data provide evidence for an interconnection between QS and AAB cellulose biofilm formation as well as QQ activity of the GqqA protein. Electronic supplementary material The online version of this article (doi:10.1186/s12934-016-0482-y) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Maria José Valera
- Biotecnología Enológica. Dept. Bioquímica i Biotecnologia, Facultat d'Enologia, Universitat Rovira i Virgili, C/Marcel.lí Domingo s/n., 43007, Tarragona, Spain
| | - Albert Mas
- Biotecnología Enológica. Dept. Bioquímica i Biotecnologia, Facultat d'Enologia, Universitat Rovira i Virgili, C/Marcel.lí Domingo s/n., 43007, Tarragona, Spain
| | - Wolfgang R Streit
- Abteilung für Mikrobiologie und Biotechnologie, Biozentrum Klein Flottbek, Universität Hamburg, Ohnhorststr. 18, 22609, Hamburg, Germany
| | - Estibaliz Mateo
- Biotecnología Enológica. Dept. Bioquímica i Biotecnologia, Facultat d'Enologia, Universitat Rovira i Virgili, C/Marcel.lí Domingo s/n., 43007, Tarragona, Spain. .,Departamento de Inmunología, Microbiología y Parasitología, Facultad de Medicina y Odontología, Universidad del País Vasco/Euskal Herriko Unibertsitatea UPV/EHU, Barrio Sarriena s/n., 48940, Leioa, Spain.
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191
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Liu W, Ran C, Liu Z, Gao Q, Xu S, Ringø E, Myklebust R, Gu Z, Zhou Z. Effects of dietary Lactobacillus plantarum and AHL lactonase on the control of Aeromonas hydrophila infection in tilapia. Microbiologyopen 2016; 5:687-99. [PMID: 27098117 PMCID: PMC4985601 DOI: 10.1002/mbo3.362] [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: 01/08/2016] [Revised: 03/06/2016] [Accepted: 03/09/2016] [Indexed: 11/09/2022] Open
Abstract
This study addressed the effects of dietary Lactobacillus plantarum or/and N-acylated homoserine lactonase (AHL lactonase) on controlling Aeromonas hydrophila infection in juvenile hybrid tilapia (Oreochromis niloticus♀ × O. aureus ♂). Fish were fed Lb. plantarum subsp. plantarum strain JCM1149 (10(8) CFU/g feed) or/and AHL lactonase AIO6 (4 U/g) and were exposed to a chronic challenge of A. hydrophila NJ-1 (10(5) cells/mL) for 14 days. Intestinal (foregut) alkaline phosphatase (IAP) activities were evaluated 1 day post challenge to reflect the resistance of fish against A. hydrophila infection. Parallel groups of fish with the same dietary assignments while unchallenged were also included to investigate the effect of dietary Lb. plantarum or/and AIO6 supplementation on gut health of tilapia. The results showed that IAP activity was significantly lower in fish fed with diets supplemented with Lb. plantarum JCM1149 or the combination of Lb. plantarum JCM1149 and AIO6, indicating enhanced resistance against A. hydrophila. Light microscopy and transmission electron microscopy images of foregut revealed damage caused by A. hydrophila NJ-1, but dietary Lb. plantarumJCM1149 or/and AIO6 significantly alleviated the damages. Compared to the fish immersed in A. hydrophila NJ-1, dietary Lb. plantarum JCM1149 or AIO6 could maintain the microvilli length in the foregut of tilapia. However, among the unchallenged groups of fish, the microvilli length in the foregut of tilapia fed AIO6 (singly or combination) and the microvilli density of tilapia fed AIO6 (singly) were significantly lower than those of the control, though the microvilli density in the combination treatment was significantly improved. Additionally, the dietary Lb. plantarum JCM1149 could down-regulate the expression of stress-related gene in the gut after the acute phase. In conclusion, the dietary Lb. plantarum JCM1149 is recommended to control the A. hydrophila infection in tilapia.
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Affiliation(s)
- Wenshu Liu
- Key Laboratory of Freshwater Biodiversity Conservation and Utilization, Ministry of Agriculture, College of Fisheries, Huazhong Agricultural University, Wuhan, Hubei, 430070, China.,Key Laboratory for Feed Biotechnology of the Ministry of Agriculture, Feed Research Institute, Chinese Academy of Agricultural Sciences, Beijing, 100081, China.,Institute of Animal Husbandry and Veterinary, Jiangxi Academy of Agricultural Science, Nanchang, Jiangxi, 330200, China
| | - Chao Ran
- Key Laboratory for Feed Biotechnology of the Ministry of Agriculture, Feed Research Institute, Chinese Academy of Agricultural Sciences, Beijing, 100081, China
| | - Zhi Liu
- Key Laboratory for Feed Biotechnology of the Ministry of Agriculture, Feed Research Institute, Chinese Academy of Agricultural Sciences, Beijing, 100081, China
| | - Qian Gao
- College of Fisheries and Life Science, Shanghai Ocean University, Shanghai, China
| | - Shude Xu
- Key Laboratory for Feed Biotechnology of the Ministry of Agriculture, Feed Research Institute, Chinese Academy of Agricultural Sciences, Beijing, 100081, China
| | - Einar Ringø
- Faculty of Biosciences, Fisheries and Economics, Norwegian College of Fishery Science, UiT The Arctic University of Norway, Tromsø, Norway
| | - Reidar Myklebust
- Institute of Anatomy and Cell Biology, University of Bergen, Bergen, Norway
| | - Zemao Gu
- Key Laboratory of Freshwater Biodiversity Conservation and Utilization, Ministry of Agriculture, College of Fisheries, Huazhong Agricultural University, Wuhan, Hubei, 430070, China
| | - Zhigang Zhou
- Key Laboratory for Feed Biotechnology of the Ministry of Agriculture, Feed Research Institute, Chinese Academy of Agricultural Sciences, Beijing, 100081, China
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192
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Abstract
Worldwide, infectious diseases are one of the leading causes of death among children. At least 65% of all infections are caused by the biofilm mode of bacterial growth. Bacteria colonise surfaces and grow as multicellular biofilm communities surrounded by a polymeric matrix as a common survival strategy. These sessile communities endow bacteria with high tolerance to antimicrobial agents and hence cause persistent and chronic bacterial infections, such as dental caries, periodontitis, otitis media, cystic fibrosis and pneumonia. The highly complex nature and the rapid adaptability of the biofilm population impede our understanding of the process of biofilm formation, but an important role for oxygen-binding proteins herein is clear. Much research on this bacterial lifestyle is already performed, from genome/proteome analysis to in vivo antibiotic susceptibility testing, but without significant progress in biofilm treatment or eradication. This review will present the multiple challenges of biofilm research and discuss possibilities to cross these barriers in future experimental studies.
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Affiliation(s)
- Joke Donné
- Protein Chemistry, Proteomics and Epigenetic Signalling (PPES), Department of Biomedical Sciences, University of Antwerp, Antwerp, Belgium
| | - Sylvia Dewilde
- Protein Chemistry, Proteomics and Epigenetic Signalling (PPES), Department of Biomedical Sciences, University of Antwerp, Antwerp, Belgium.
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193
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Shin D, Frane ND, Brecht RM, Keeler J, Nagarajan R. A Comparative Analysis of Acyl-Homoserine Lactone Synthase Assays. Chembiochem 2015; 16:2651-9. [PMID: 26456773 DOI: 10.1002/cbic.201500387] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2015] [Indexed: 11/10/2022]
Abstract
Quorum sensing is cell-to-cell communication that allows bacteria to coordinate attacks on their hosts by inducing virulent gene expression, biofilm production, and other cellular functions, including antibiotic resistance. AHL synthase enzymes synthesize N-acyl-l-homoserine lactones, commonly referred to as autoinducers, to facilitate quorum sensing in Gram-negative bacteria. Studying the synthases, however, has proven to be a difficult road. Two assays, including a radiolabeled assay and a colorimetric (DCPIP) assay are well-documented in literature to study AHL synthases. In this paper, we describe additional methods that include an HPLC-based, C-S bond cleavage and coupled assays to investigate this class of enzymes. In addition, we compare and contrast each assay for both acyl-CoA- and acyl-ACP-utilizing synthases. The expanded toolkit described in this study should facilitate mechanistic studies on quorum sensing signal synthases and expedite discovery of antivirulent compounds.
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Affiliation(s)
- Daniel Shin
- Department of Chemistry and Biochemistry, Boise State University, 1910 University Drive, Boise, ID, 83725, USA
| | - Nicole D Frane
- Department of Chemistry and Biochemistry, Boise State University, 1910 University Drive, Boise, ID, 83725, USA
| | - Ryan M Brecht
- Department of Chemistry and Biochemistry, Boise State University, 1910 University Drive, Boise, ID, 83725, USA.,Department of Molecular Biophysics and Biochemistry, Yale University, 260 Whitney Avenue, PO Box 208114, New Haven, CT, 06520-8114, USA
| | - Jesse Keeler
- Department of Chemistry, Northwest Nazarene University, Nampa, ID, 83686, USA.,Loma Linda School of Medicine, Coleman Pavilion, 11175 Campus Street, Loma Linda, CA, 92350, USA
| | - Rajesh Nagarajan
- Department of Chemistry and Biochemistry, Boise State University, 1910 University Drive, Boise, ID, 83725, USA.
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194
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Rückert C, Birmes FS, Müller C, Niewerth H, Winkler A, Fetzner S, Kalinowski J. Complete genome sequence of Rhodococcus erythropolis BG43 (DSM 46869), a degrader of Pseudomonas aeruginosa quorum sensing signal molecules. J Biotechnol 2015. [PMID: 26210289 DOI: 10.1016/j.jbiotec.2015.07.014] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Rhodococcus erythropolis BG43 was isolated from soil and characterized as a degrader of the quorum sensing signal molecules 2-heptyl-3-hydroxy-4(1H)-quinolone (the Pseudomonas quinolone signal, PQS) and 2-heptyl-4(1H)-quinolone, produced by Pseudomonas aeruginosa. The complete genome of R. erythropolis BG43 consists of a circular chromosome and three plasmids, one of them circular and two linear ones. In total, 6158 protein-coding regions were identified. With this genome sequence, the genetic basis of its quorum-quenching ability and possible biotechnological applications can be explored further.
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Affiliation(s)
- Christian Rückert
- Technology Platform Genomics, Center for Biotechnology (CeBiTec), Bielefeld University, Sequenz 1, 33615 Bielefeld, Germany
| | - Franziska S Birmes
- Institute of Molecular Microbiology and Biotechnology, University of Münster, Corrensstraße 3, 48149 Münster, Germany
| | - Christine Müller
- Institute of Molecular Microbiology and Biotechnology, University of Münster, Corrensstraße 3, 48149 Münster, Germany
| | - Heiko Niewerth
- Institute of Molecular Microbiology and Biotechnology, University of Münster, Corrensstraße 3, 48149 Münster, Germany
| | - Anika Winkler
- Technology Platform Genomics, Center for Biotechnology (CeBiTec), Bielefeld University, Sequenz 1, 33615 Bielefeld, Germany
| | - Susanne Fetzner
- Institute of Molecular Microbiology and Biotechnology, University of Münster, Corrensstraße 3, 48149 Münster, Germany.
| | - Jörn Kalinowski
- Technology Platform Genomics, Center for Biotechnology (CeBiTec), Bielefeld University, Sequenz 1, 33615 Bielefeld, Germany.
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