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Chakraborty A, Bandyopadhaya A, Singh V, Kovacic F, Cha S, Oldham W, Tzika AA, Rahme L. The Bacterial Quorum-Sensing Signal 2-Aminoacetophenone Rewires Immune Cell Bioenergetics through the PGC-1α/ERRα Axis to Mediate Tolerance to Infection. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.02.26.582124. [PMID: 38464050 PMCID: PMC10925214 DOI: 10.1101/2024.02.26.582124] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 03/12/2024]
Abstract
How bacterial pathogens exploit host metabolism to promote immune tolerance and persist in infected hosts remains elusive. To achieve this, we show that Pseudomonas aeruginosa (PA), a recalcitrant pathogen, utilizes the quorum sensing (QS) signal 2-aminoacetophenone (2-AA). Here, we unveil how 2-AA-driven immune tolerization causes distinct metabolic perturbations in macrophages mitochondrial respiration and bioenergetics. We present evidence indicating that these effects stem from decreased pyruvate transport into mitochondria. This reduction is attributed to decreased expression of the mitochondrial pyruvate carrier (MPC1), which is mediated by diminished expression and nuclear presence of its transcriptional regulator, estrogen-related nuclear receptor alpha (ERRα). Consequently, ERRα exhibits weakened binding to the MPC1 promoter. This outcome arises from the impaired interaction between ERRα and the peroxisome proliferator-activated receptor gamma coactivator 1-alpha (PGC-1α). Ultimately, this cascade results in diminished pyruvate influx into mitochondria and, consequently reduced ATP production in tolerized macrophages. Exogenously added ATP in infected macrophages restores the transcript levels of MPC1 and ERRα and enhances cytokine production and intracellular bacterial clearance. Consistent with the in vitro findings, murine infection studies corroborate the 2-AA-mediated long-lasting decrease in ATP and acetyl-CoA and its association with PA persistence, further supporting this QS signaling molecule as the culprit of the host bioenergetic alterations and PA persistence. These findings unveil 2-AA as a modulator of cellular immunometabolism and reveal an unprecedented mechanism of host tolerance to infection involving the PGC-1α/ERRα axis in its influence on MPC1/OXPHOS-dependent energy production and PA clearance. These paradigmatic findings pave the way for developing treatments to bolster host resilience to pathogen-induced damage. Given that QS is a common characteristic of prokaryotes, it is likely that 2-AA-like molecules with similar functions may be present in other pathogens.
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Gentile R, Modric M, Thiele B, Jaeger KE, Kovacic F, Schott-Verdugo S, Gohlke H. Molecular Mechanisms Underlying Medium-Chain Free Fatty Acid-Regulated Activity of the Phospholipase PlaF from Pseudomonas aeruginosa. JACS AU 2024; 4:958-973. [PMID: 38559719 PMCID: PMC10976570 DOI: 10.1021/jacsau.3c00725] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/17/2023] [Revised: 01/08/2024] [Accepted: 01/09/2024] [Indexed: 04/04/2024]
Abstract
PlaF is a membrane-bound phospholipase A1 from Pseudomonas aeruginosa that is involved in remodeling membrane glycerophospholipids (GPLs) and modulating virulence-associated signaling and metabolic pathways. Previously, we identified the role of medium-chain free fatty acids (FFAs) in inhibiting PlaF activity and promoting homodimerization, yet the underlying molecular mechanism remained elusive. Here, we used unbiased and biased molecular dynamics simulations and free energy computations to assess how PlaF interacts with FFAs localized in the water milieu surrounding the bilayer or within the bilayer and how these interactions regulate PlaF activity. Medium-chain FFAs localized in the upper bilayer leaflet can stabilize inactive dimeric PlaF, likely through interactions with charged surface residues, as has been experimentally validated. Potential of mean force (PMF) computations indicate that membrane-bound FFAs may facilitate the activation of monomeric PlaF by lowering the activation barrier for changing into a tilted, active configuration. We estimated that the coupled equilibria of PlaF monomerization-dimerization and tilting at the physiological concentration of PlaF lead to the majority of PlaF forming inactive dimers when in a cell membrane loaded with decanoic acid (C10). This is in agreement with a suggested in vivo product feedback loop and gas chromatography-mass spectrometry profiling results, indicating that PlaF catalyzes the release of C10 from P. aeruginosa membranes. Additionally, we found that C10 in the water milieu can access the catalytic site of active monomeric PlaF, contributing to the competitive component of C10-mediated PlaF inhibition. Our study provides mechanistic insights into how medium-chain FFAs may regulate the activity of PlaF, a potential bacterial drug target.
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Affiliation(s)
- Rocco Gentile
- Institute
for Pharmaceutical and Medicinal Chemistry, Heinrich Heine University Düsseldorf, 40225 Düsseldorf, Germany
| | - Matea Modric
- Institute
of Molecular Enzyme Technology, Heinrich
Heine University Düsseldorf, Forschungszentrum Jülich
GmbH, 52425 Jülich, Germany
| | - Björn Thiele
- Institute
of Bio- and Geosciences (IBG-2: Plant Sciences and IBG-3: Agrosphere), Forschungszentrum Jülich GmbH, 52425 Jülich, Germany
| | - Karl-Erich Jaeger
- Institute
of Molecular Enzyme Technology, Heinrich
Heine University Düsseldorf, Forschungszentrum Jülich
GmbH, 52425 Jülich, Germany
- Institute
of Bio- and Geosciences (IBG-1: Biotechnology), Forschungszentrum Jülich GmbH, 52425 Jülich, Germany
| | - Filip Kovacic
- Institute
of Molecular Enzyme Technology, Heinrich
Heine University Düsseldorf, Forschungszentrum Jülich
GmbH, 52425 Jülich, Germany
| | - Stephan Schott-Verdugo
- Institute
of Bio- and Geosciences (IBG-4: Bioinformatics), Forschungszentrum Jülich GmbH, 52425 Jülich, Germany
| | - Holger Gohlke
- Institute
for Pharmaceutical and Medicinal Chemistry, Heinrich Heine University Düsseldorf, 40225 Düsseldorf, Germany
- Institute
of Bio- and Geosciences (IBG-4: Bioinformatics), Forschungszentrum Jülich GmbH, 52425 Jülich, Germany
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3
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Trottier MC, de Oliveira Pereira T, Groleau MC, Hoffman LR, Dandekar AA, Déziel E. The end of the reign of a "master regulator''? A defect in function of the LasR quorum sensing regulator is a common feature of Pseudomonas aeruginosa isolates. mBio 2024; 15:e0237623. [PMID: 38315035 PMCID: PMC10936206 DOI: 10.1128/mbio.02376-23] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2024] Open
Abstract
Pseudomonas aeruginosa, a bacterium causing infections in immunocompromised individuals, regulates several of its virulence functions using three interlinked quorum sensing (QS) systems (las, rhl, and pqs). Despite its presumed importance in regulating virulence, dysfunction of the las system regulator LasR occurs frequently in strains isolated from various environments, including clinical infections. This newfound abundance of LasR-defective strains calls into question existing hypotheses regarding their selection. Indeed, current assumptions concerning factors driving the emergence of LasR-deficient isolates and the role of LasR in the QS hierarchy must be reconsidered. Here, we propose that LasR is not the primary master regulator of QS in all P. aeruginosa genetic backgrounds, even though it remains ecologically significant. We also revisit and complement current knowledge on the ecology of LasR-dependent QS in P. aeruginosa, discuss the hypotheses explaining the putative adaptive benefits of selecting against LasR function, and consider the implications of this renewed understanding.
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Affiliation(s)
- Mylène C. Trottier
- Centre Armand-Frappier Santé Biotechnologie, Institut National de la Recherche Scientifique (INRS), Laval, Québec, Canada
| | - Thays de Oliveira Pereira
- Centre Armand-Frappier Santé Biotechnologie, Institut National de la Recherche Scientifique (INRS), Laval, Québec, Canada
| | - Marie-Christine Groleau
- Centre Armand-Frappier Santé Biotechnologie, Institut National de la Recherche Scientifique (INRS), Laval, Québec, Canada
| | - Lucas R. Hoffman
- Departments of Pediatrics and Microbiology, University of Washington, Seattle, Washington, USA
| | - Ajai A. Dandekar
- Departments of Medicine and Microbiology, University of Washington, Seattle, Washington, USA
| | - Eric Déziel
- Centre Armand-Frappier Santé Biotechnologie, Institut National de la Recherche Scientifique (INRS), Laval, Québec, Canada
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4
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Juříková T, Mácha H, Lupjanová V, Pluháček T, Marešová H, Papoušková B, Luptáková D, Patil RH, Benada O, Grulich M, Palyzová A. The Deciphering of Growth-Dependent Strategies for Quorum-Sensing Networks in Pseudomonas aeruginosa. Microorganisms 2023; 11:2329. [PMID: 37764173 PMCID: PMC10534576 DOI: 10.3390/microorganisms11092329] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2023] [Revised: 08/31/2023] [Accepted: 09/13/2023] [Indexed: 09/29/2023] Open
Abstract
Pseudomonas aeruginosa is recognized as a significant cause of morbidity and mortality among nosocomial pathogens. In respiratory infections, P. aeruginosa acts not only as a single player but also collaborates with the opportunistic fungal pathogen Aspergillus fumigatus. This study introduced a QS molecule portfolio as a potential new biomarker that affects the secretion of virulence factors and biofilm formation. The quantitative levels of QS molecules, including 3-o-C12-HSL, 3-o-C8-HSL, C4-HSL, C6-HSL, HHQ, PQS, and PYO, measured using mass spectrometry in a monoculture, indicated metabolic changes during the transition from planktonic to sessile cells. In the co-cultures with A. fumigatus, the profile of abundant QS molecules was reduced to 3-o-C12-HSL, C4-HSL, PQS, and PYO. A decrease in C4-HSL by 50% to 170.6 ± 11.8 ng/mL and an increase 3-o-C12-HSL by 30% up to 784.4 ± 0.6 ng/mL were detected at the stage of the coverage of the hyphae with bacteria. Using scanning electron microscopy, we showed the morphological stages of the P. aeruginosa biofilm, such as cell aggregates, maturated biofilm, and cell dispersion. qPCR quantification of the genome equivalents of both microorganisms suggested that they exhibited an interplay strategy rather than antagonism. This is the first study demonstrating the quantitative growth-dependent appearance of QS molecule secretion in a monoculture of P. aeruginosa and a co-culture with A. fumigatus.
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Affiliation(s)
- Tereza Juříková
- Institute of Microbiology of the Czech Academy of Sciences, Videnska 1083, 142 20 Prague, Czech Republic; (T.J.); (H.M.); (V.L.); (H.M.); (D.L.); (R.H.P.); (O.B.); (M.G.)
| | - Hynek Mácha
- Institute of Microbiology of the Czech Academy of Sciences, Videnska 1083, 142 20 Prague, Czech Republic; (T.J.); (H.M.); (V.L.); (H.M.); (D.L.); (R.H.P.); (O.B.); (M.G.)
- Department of Analytical Chemistry, Faculty of Science, Palacky University, 17. Listopadu 12, 771 46 Olomouc, Czech Republic; (T.P.); (B.P.)
| | - Vanda Lupjanová
- Institute of Microbiology of the Czech Academy of Sciences, Videnska 1083, 142 20 Prague, Czech Republic; (T.J.); (H.M.); (V.L.); (H.M.); (D.L.); (R.H.P.); (O.B.); (M.G.)
| | - Tomáš Pluháček
- Department of Analytical Chemistry, Faculty of Science, Palacky University, 17. Listopadu 12, 771 46 Olomouc, Czech Republic; (T.P.); (B.P.)
| | - Helena Marešová
- Institute of Microbiology of the Czech Academy of Sciences, Videnska 1083, 142 20 Prague, Czech Republic; (T.J.); (H.M.); (V.L.); (H.M.); (D.L.); (R.H.P.); (O.B.); (M.G.)
| | - Barbora Papoušková
- Department of Analytical Chemistry, Faculty of Science, Palacky University, 17. Listopadu 12, 771 46 Olomouc, Czech Republic; (T.P.); (B.P.)
| | - Dominika Luptáková
- Institute of Microbiology of the Czech Academy of Sciences, Videnska 1083, 142 20 Prague, Czech Republic; (T.J.); (H.M.); (V.L.); (H.M.); (D.L.); (R.H.P.); (O.B.); (M.G.)
| | - Rutuja H. Patil
- Institute of Microbiology of the Czech Academy of Sciences, Videnska 1083, 142 20 Prague, Czech Republic; (T.J.); (H.M.); (V.L.); (H.M.); (D.L.); (R.H.P.); (O.B.); (M.G.)
- Department of Analytical Chemistry, Faculty of Science, Palacky University, 17. Listopadu 12, 771 46 Olomouc, Czech Republic; (T.P.); (B.P.)
| | - Oldřich Benada
- Institute of Microbiology of the Czech Academy of Sciences, Videnska 1083, 142 20 Prague, Czech Republic; (T.J.); (H.M.); (V.L.); (H.M.); (D.L.); (R.H.P.); (O.B.); (M.G.)
| | - Michal Grulich
- Institute of Microbiology of the Czech Academy of Sciences, Videnska 1083, 142 20 Prague, Czech Republic; (T.J.); (H.M.); (V.L.); (H.M.); (D.L.); (R.H.P.); (O.B.); (M.G.)
| | - Andrea Palyzová
- Institute of Microbiology of the Czech Academy of Sciences, Videnska 1083, 142 20 Prague, Czech Republic; (T.J.); (H.M.); (V.L.); (H.M.); (D.L.); (R.H.P.); (O.B.); (M.G.)
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5
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Ghosh M, Raghav S, Ghosh P, Maity S, Mohela K, Jain D. Structural analysis of novel drug targets for mitigation of Pseudomonas aeruginosa biofilms. FEMS Microbiol Rev 2023; 47:fuad054. [PMID: 37771093 DOI: 10.1093/femsre/fuad054] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2023] [Revised: 09/20/2023] [Accepted: 09/27/2023] [Indexed: 09/30/2023] Open
Abstract
Pseudomonas aeruginosa is an opportunistic human pathogen responsible for acute and chronic, hard to treat infections. Persistence of P. aeruginosa is due to its ability to develop into biofilms, which are sessile bacterial communities adhered to substratum and encapsulated in layers of self-produced exopolysaccharides. These biofilms provide enhanced protection from the host immune system and resilience towards antibiotics, which poses a challenge for treatment. Various strategies have been expended for combating biofilms, which involve inhibiting biofilm formation or promoting their dispersal. The current remediation approaches offer some hope for clinical usage, however, treatment and eradication of preformed biofilms is still a challenge. Thus, identifying novel targets and understanding the detailed mechanism of biofilm regulation becomes imperative. Structure-based drug discovery (SBDD) provides a powerful tool that exploits the knowledge of atomic resolution details of the targets to search for high affinity ligands. This review describes the available structural information on the putative target protein structures that can be utilized for high throughput in silico drug discovery against P. aeruginosa biofilms. Integrating available structural information on the target proteins in readily accessible format will accelerate the process of drug discovery.
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Affiliation(s)
- Moumita Ghosh
- Transcription Regulation Lab, Regional Centre for Biotechnology, NCR Biotech Science Cluster, 3rd Milestone, Faridabad-Gurugram Expressway, Faridabad, Haryana-121001, India
| | - Shikha Raghav
- Transcription Regulation Lab, Regional Centre for Biotechnology, NCR Biotech Science Cluster, 3rd Milestone, Faridabad-Gurugram Expressway, Faridabad, Haryana-121001, India
| | - Puja Ghosh
- Transcription Regulation Lab, Regional Centre for Biotechnology, NCR Biotech Science Cluster, 3rd Milestone, Faridabad-Gurugram Expressway, Faridabad, Haryana-121001, India
| | - Swagatam Maity
- Transcription Regulation Lab, Regional Centre for Biotechnology, NCR Biotech Science Cluster, 3rd Milestone, Faridabad-Gurugram Expressway, Faridabad, Haryana-121001, India
| | - Kavery Mohela
- Transcription Regulation Lab, Regional Centre for Biotechnology, NCR Biotech Science Cluster, 3rd Milestone, Faridabad-Gurugram Expressway, Faridabad, Haryana-121001, India
| | - Deepti Jain
- Transcription Regulation Lab, Regional Centre for Biotechnology, NCR Biotech Science Cluster, 3rd Milestone, Faridabad-Gurugram Expressway, Faridabad, Haryana-121001, India
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6
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Giallonardi G, Letizia M, Mellini M, Frangipani E, Halliday N, Heeb S, Cámara M, Visca P, Imperi F, Leoni L, Williams P, Rampioni G. Alkyl-quinolone-dependent quorum sensing controls prophage-mediated autolysis in Pseudomonas aeruginosa colony biofilms. Front Cell Infect Microbiol 2023; 13:1183681. [PMID: 37305419 PMCID: PMC10250642 DOI: 10.3389/fcimb.2023.1183681] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2023] [Accepted: 05/02/2023] [Indexed: 06/13/2023] Open
Abstract
Pseudomonas aeruginosa is a model quorum sensing (QS) pathogen with three interconnected QS circuits that control the production of virulence factors and antibiotic tolerant biofilms. The pqs QS system of P. aeruginosa is responsible for the biosynthesis of diverse 2-alkyl-4-quinolones (AQs), of which 2-heptyl-4-hydroxyquinoline (HHQ) and 2-heptyl-3-hydroxy-4(1H)-quinolone (PQS) function as QS signal molecules. Transcriptomic analyses revealed that HHQ and PQS influenced the expression of multiple genes via PqsR-dependent and -independent pathways whereas 2-heptyl-4-hydroxyquinoline N-oxide (HQNO) had no effect on P. aeruginosa transcriptome. HQNO is a cytochrome bc 1 inhibitor that causes P. aeruginosa programmed cell death and autolysis. However, P. aeruginosa pqsL mutants unable to synthesize HQNO undergo autolysis when grown as colony biofilms. The mechanism by which such autolysis occurs is not understood. Through the generation and phenotypic characterization of multiple P. aeruginosa PAO1 mutants producing altered levels of AQs in different combinations, we demonstrate that mutation of pqsL results in the accumulation of HHQ which in turn leads to Pf4 prophage activation and consequently autolysis. Notably, the effect of HHQ on Pf4 activation is not mediated via its cognate receptor PqsR. These data indicate that the synthesis of HQNO in PAO1 limits HHQ-induced autolysis mediated by Pf4 in colony biofilms. A similar phenomenon is shown to occur in P. aeruginosa cystic fibrosis (CF) isolates, in which the autolytic phenotype can be abrogated by ectopic expression of pqsL.
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Affiliation(s)
| | | | - Marta Mellini
- Department of Science, University Roma Tre, Rome, Italy
| | | | - Nigel Halliday
- National Biofilms Innovation Centre, Biodiscovery Institute and School of Life Sciences, University of Nottingham, Nottingham, United Kingdom
| | - Stephan Heeb
- National Biofilms Innovation Centre, Biodiscovery Institute and School of Life Sciences, University of Nottingham, Nottingham, United Kingdom
| | - Miguel Cámara
- National Biofilms Innovation Centre, Biodiscovery Institute and School of Life Sciences, University of Nottingham, Nottingham, United Kingdom
| | - Paolo Visca
- Department of Science, University Roma Tre, Rome, Italy
- IRCCS Fondazione Santa Lucia, Rome, Italy
- NBFC, National Biodiversity Future Center, Palermo, Italy
| | - Francesco Imperi
- Department of Science, University Roma Tre, Rome, Italy
- IRCCS Fondazione Santa Lucia, Rome, Italy
- NBFC, National Biodiversity Future Center, Palermo, Italy
| | - Livia Leoni
- Department of Science, University Roma Tre, Rome, Italy
| | - Paul Williams
- National Biofilms Innovation Centre, Biodiscovery Institute and School of Life Sciences, University of Nottingham, Nottingham, United Kingdom
| | - Giordano Rampioni
- Department of Science, University Roma Tre, Rome, Italy
- IRCCS Fondazione Santa Lucia, Rome, Italy
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7
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Caliskan M, Poschmann G, Gudzuhn M, Waldera-Lupa D, Molitor R, Strunk CH, Streit WR, Jaeger KE, Stühler K, Kovacic F. Pseudomonas aeruginosa responds to altered membrane phospholipid composition by adjusting the production of two-component systems, proteases and iron uptake proteins. Biochim Biophys Acta Mol Cell Biol Lipids 2023; 1868:159317. [PMID: 37054907 DOI: 10.1016/j.bbalip.2023.159317] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/24/2022] [Revised: 03/16/2023] [Accepted: 03/21/2023] [Indexed: 04/15/2023]
Abstract
Membrane protein and phospholipid (PL) composition changes in response to environmental cues and during infections. To achieve these, bacteria use adaptation mechanisms involving covalent modification and remodelling of the acyl chain length of PLs. However, little is known about bacterial pathways regulated by PLs. Here, we investigated proteomic changes in the biofilm of P. aeruginosa phospholipase mutant (∆plaF) with altered membrane PL composition. The results revealed profound alterations in the abundance of many biofilm-related two-component systems (TCSs), including accumulation of PprAB, a key regulator of the transition to biofilm. Furthermore, a unique phosphorylation pattern of transcriptional regulators, transporters and metabolic enzymes, as well as differential production of several proteases, in ∆plaF, indicate that PlaF-mediated virulence adaptation involves complex transcriptional and posttranscriptional response. Moreover, proteomics and biochemical assays revealed the depletion of pyoverdine-mediated iron uptake pathway proteins in ∆plaF, while proteins from alternative iron-uptake systems were accumulated. These suggest that PlaF may function as a switch between different iron-acquisition pathways. The observation that PL-acyl chain modifying and PL synthesis enzymes were overproduced in ∆plaF reveals the interconnection of degradation, synthesis and modification of PLs for proper membrane homeostasis. Although the precise mechanism by which PlaF simultaneously affects multiple pathways remains to be elucidated, we suggest that alteration of PL composition in ∆plaF plays a role for the global adaptive response in P. aeruginosa mediated by TCSs and proteases. Our study revealed the global regulation of virulence and biofilm by PlaF and suggests that targeting this enzyme may have therapeutic potential.
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Affiliation(s)
- Muttalip Caliskan
- Institute of Molecular Enzyme Technology, Heinrich Heine University Düsseldorf, Jülich, Germany
| | - Gereon Poschmann
- Institute of Molecular Medicine, Proteome Research, University Hospital and Medical Faculty, Heinrich Heine University Düsseldorf, Düsseldorf, Germany
| | - Mirja Gudzuhn
- Department of Microbiology and Biotechnology, University of Hamburg, Ohnhorststr. 18, 22609 Hamburg, Germany
| | - Daniel Waldera-Lupa
- Institute of Molecular Medicine, Proteome Research, University Hospital and Medical Faculty, Heinrich Heine University Düsseldorf, Düsseldorf, Germany
| | - Rebecka Molitor
- Institute of Molecular Enzyme Technology, Heinrich Heine University Düsseldorf, Jülich, Germany
| | | | - Wolfgang R Streit
- Department of Microbiology and Biotechnology, University of Hamburg, Ohnhorststr. 18, 22609 Hamburg, Germany
| | - Karl-Erich Jaeger
- Institute of Molecular Enzyme Technology, Heinrich Heine University Düsseldorf, Jülich, Germany; Institute of Bio- and Geosciences IBG-1: Biotechnology, Forschungszentrum Jülich GmbH, Jülich, Germany
| | - Kai Stühler
- Institute of Molecular Medicine, Proteome Research, University Hospital and Medical Faculty, Heinrich Heine University Düsseldorf, Düsseldorf, Germany; Molecular Proteomics Laboratory, Biologisch-Medizinisches Forschungszentrum, Heinrich-Heine-University, Düsseldorf, Düsseldorf, Germany
| | - Filip Kovacic
- Institute of Molecular Enzyme Technology, Heinrich Heine University Düsseldorf, Jülich, Germany.
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8
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Beenker WAG, Hoeksma J, Bannier-Hélaouët M, Clevers H, den Hertog J. Paecilomycone Inhibits Quorum Sensing in Gram-Negative Bacteria. Microbiol Spectr 2023; 11:e0509722. [PMID: 36920212 PMCID: PMC10100902 DOI: 10.1128/spectrum.05097-22] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2022] [Accepted: 02/20/2023] [Indexed: 03/16/2023] Open
Abstract
Pseudomonas aeruginosa is an opportunistic pathogen that causes major health care concerns due to its virulence and high intrinsic resistance to antimicrobial agents. Therefore, new treatments are greatly needed. An interesting approach is to target quorum sensing (QS). QS regulates the production of a wide variety of virulence factors and biofilm formation in P. aeruginosa. This study describes the identification of paecilomycone as an inhibitor of QS in both Chromobacterium violaceum and P. aeruginosa. Paecilomycone strongly inhibited the production of virulence factors in P. aeruginosa, including various phenazines, and biofilm formation. In search of the working mechanism, we found that paecilomycone inhibited the production of 4-hydroxy-2-heptylquinoline (HHQ) and 3,4-dihydroxy-2-heptylquinoline (PQS), but not 2'-aminoacetophenone (2-AA). Therefore, we suggest that paecilomycone affects parts of QS in P. aeruginosa by targeting the PqsBC complex and alternative targets or alters processes that influence the enzymatic activity of the PqsBC complex. The toxicity of paecilomycone toward eukaryotic cells and organisms was low, making it an interesting lead for further clinical research. IMPORTANCE Antibiotics are becoming less effective against bacterial infections due to the evolution of resistance among bacteria. Pseudomonas aeruginosa is a Gram-negative pathogen that causes major health care concerns and is difficult to treat due to its high intrinsic resistance to antimicrobial agents. Therefore, new targets are needed, and an interesting approach is to target quorum sensing (QS). QS is the communication system in bacteria that regulates multiple pathways, including the production of virulence factors and biofilm formation, which leads to high toxicity in the host and low sensitivity to antibiotics, respectively. We found a compound, named paecilomycone, that inhibited biofilm formation and the production of various virulence factors in P. aeruginosa. The toxicity of paecilomycone toward eukaryotic cells and organisms was low, making it an interesting lead for further clinical research.
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Affiliation(s)
- Wouter A. G. Beenker
- Hubrecht Institute-KNAW and University Medical Center Utrecht, Utrecht, The Netherlands
| | - Jelmer Hoeksma
- Hubrecht Institute-KNAW and University Medical Center Utrecht, Utrecht, The Netherlands
| | - Marie Bannier-Hélaouët
- Hubrecht Institute-KNAW and University Medical Center Utrecht, Utrecht, The Netherlands
- Oncode Institute, Hubrecht Institute-KNAW and University Medical Center, Utrecht, The Netherlands
| | - Hans Clevers
- Hubrecht Institute-KNAW and University Medical Center Utrecht, Utrecht, The Netherlands
- Oncode Institute, Hubrecht Institute-KNAW and University Medical Center, Utrecht, The Netherlands
| | - Jeroen den Hertog
- Hubrecht Institute-KNAW and University Medical Center Utrecht, Utrecht, The Netherlands
- Institute Biology Leiden, Leiden University, Leiden, The Netherlands
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9
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Pan X, Liang H, Zhao X, Zhang Q, Chen L, Yue Z, Yin L, Jin Y, Bai F, Cheng Z, Bartlam M, Wu W. Regulatory and structural mechanisms of PvrA-mediated regulation of the PQS quorum-sensing system and PHA biosynthesis in Pseudomonas aeruginosa. Nucleic Acids Res 2023; 51:2691-2708. [PMID: 36744476 PMCID: PMC10085694 DOI: 10.1093/nar/gkad059] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2022] [Revised: 01/17/2023] [Accepted: 01/20/2023] [Indexed: 02/07/2023] Open
Abstract
Pseudomonas aeruginosa is capable of causing acute and chronic infections in various host tissues, which depends on its abilities to effectively utilize host-derived nutrients and produce protein virulence factors and toxic compounds. However, the regulatory mechanisms that direct metabolic intermediates towards production of toxic compounds are poorly understood. We previously identified a regulatory protein PvrA that controls genes involved in fatty acid catabolism by binding to palmitoyl-coenzyme A (CoA). In this study, transcriptomic analyses revealed that PvrA activates the Pseudomonas quinolone signal (PQS) synthesis genes, while suppressing genes for production of polyhydroxyalkanoates (PHAs). When palmitic acid was the sole carbon source, mutation of pvrA reduced production of pyocyanin and rhamnolipids due to defective PQS synthesis, but increased PHA production. We further solved the co-crystal structure of PvrA with palmitoyl-CoA and identified palmitoyl-CoA-binding residues. By using pvrA mutants, we verified the roles of the key palmitoyl-CoA-binding residues in gene regulation in response to palmitic acid. Since the PQS signal molecules, rhamnolipids and PHA synthesis pathways are interconnected by common metabolic intermediates, our results revealed a regulatory mechanism that directs carbon flux from carbon/energy storage to virulence factor production, which might be crucial for the pathogenesis.
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Affiliation(s)
- Xiaolei Pan
- State Key Laboratory of Medicinal Chemical Biology, Key Laboratory of Molecular Microbiology and Technology of the Ministry of Education, Department of Microbiology, College of Life Sciences, Nankai University, Tianjin 300071, China
| | - Han Liang
- State Key Laboratory of Medicinal Chemical Biology, Key Laboratory of Molecular Microbiology and Technology of the Ministry of Education, Department of Microbiology, College of Life Sciences, Nankai University, Tianjin 300071, China.,Tianjin Key Laboratory of Protein Science, Nankai University, Tianjin 300071, China
| | - Xinrui Zhao
- State Key Laboratory of Medicinal Chemical Biology, Key Laboratory of Molecular Microbiology and Technology of the Ministry of Education, Department of Microbiology, College of Life Sciences, Nankai University, Tianjin 300071, China
| | - Qionglin Zhang
- State Key Laboratory of Medicinal Chemical Biology, Key Laboratory of Molecular Microbiology and Technology of the Ministry of Education, Department of Microbiology, College of Life Sciences, Nankai University, Tianjin 300071, China.,Tianjin Key Laboratory of Protein Science, Nankai University, Tianjin 300071, China
| | - Lei Chen
- Department of Plant Biology and Ecology, College of Life Science Nankai University, Tianjin 300071 China
| | - Zhuo Yue
- State Key Laboratory of Medicinal Chemical Biology, Key Laboratory of Molecular Microbiology and Technology of the Ministry of Education, Department of Microbiology, College of Life Sciences, Nankai University, Tianjin 300071, China
| | - Liwen Yin
- State Key Laboratory of Medicinal Chemical Biology, Key Laboratory of Molecular Microbiology and Technology of the Ministry of Education, Department of Microbiology, College of Life Sciences, Nankai University, Tianjin 300071, China
| | - Yongxin Jin
- State Key Laboratory of Medicinal Chemical Biology, Key Laboratory of Molecular Microbiology and Technology of the Ministry of Education, Department of Microbiology, College of Life Sciences, Nankai University, Tianjin 300071, China
| | - Fang Bai
- State Key Laboratory of Medicinal Chemical Biology, Key Laboratory of Molecular Microbiology and Technology of the Ministry of Education, Department of Microbiology, College of Life Sciences, Nankai University, Tianjin 300071, China
| | - Zhihui Cheng
- State Key Laboratory of Medicinal Chemical Biology, Key Laboratory of Molecular Microbiology and Technology of the Ministry of Education, Department of Microbiology, College of Life Sciences, Nankai University, Tianjin 300071, China
| | - Mark Bartlam
- State Key Laboratory of Medicinal Chemical Biology, Key Laboratory of Molecular Microbiology and Technology of the Ministry of Education, Department of Microbiology, College of Life Sciences, Nankai University, Tianjin 300071, China.,Tianjin Key Laboratory of Protein Science, Nankai University, Tianjin 300071, China.,Nankai International Advanced Research Institute (Shenzhen Futian), Shenzhen, Guangdong 518045, China
| | - Weihui Wu
- State Key Laboratory of Medicinal Chemical Biology, Key Laboratory of Molecular Microbiology and Technology of the Ministry of Education, Department of Microbiology, College of Life Sciences, Nankai University, Tianjin 300071, China
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10
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Ernst S, Mährlein A, Ritzmann NH, Drees SL, Fetzner S. A comparative study of
N
‐hydroxylating flavoprotein monooxygenases reveals differences in kinetics and cofactor binding. FEBS J 2022; 289:5637-5655. [DOI: 10.1111/febs.16444] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2021] [Revised: 02/21/2022] [Accepted: 03/18/2022] [Indexed: 12/01/2022]
Affiliation(s)
- Simon Ernst
- Institute of Molecular Microbiology and Biotechnology University of Münster Germany
| | - Almuth Mährlein
- Institute of Molecular Microbiology and Biotechnology University of Münster Germany
| | - Niklas H. Ritzmann
- Institute of Molecular Microbiology and Biotechnology University of Münster Germany
| | - Steffen L. Drees
- Institute of Molecular Microbiology and Biotechnology University of Münster Germany
| | - Susanne Fetzner
- Institute of Molecular Microbiology and Biotechnology University of Münster Germany
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11
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Cook J, Hui JPM, Zhang J, Kember M, Berrué F, Zhang J, Cheng Z. Production of quorum sensing-related metabolites and phytoalexins during Pseudomonas aeruginosa-Brassica napus interaction. MICROBIOLOGY (READING, ENGLAND) 2022; 168. [PMID: 35980361 DOI: 10.1099/mic.0.001212] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Pseudomonas aeruginosa is an opportunistic bacterial pathogen that has been shown to interact with many organisms throughout the domains of life, including plants. How this broad-host-range bacterium interacts with each of its diverse hosts, especially the metabolites that mediate these interactions, is not completely known. In this work, we used a liquid culture root infection system to collect plant and bacterial metabolites on days 1, 3 and 5 post-P. aeruginosa (strain PA14) infection of the oilseed plant, canola (Brassica napus). Using MS-based metabolomics approaches, we identified the overproduction of quorum sensing (QS)-related (both signalling molecules and regulated products) metabolites by P. aeruginosa while interacting with canola plants. However, the P. aeruginosa infection induced the production of several phytoalexins, which is a part of the hallmark plant defence response to microbes. The QS system of PA14 appears to only mediate part of the canola-P. aeruginosa metabolomic interactions, as the use of isogenic mutant strains of each of the three QS signalling branches did not significantly affect the induction of the phytoalexin brassilexin, while induction of spirobrassinin was significantly decreased. Interestingly, a treatment of purified QS molecules in the absence of bacteria was not able to induce any phytoalexin production, suggesting that active bacterial colonization is required for eliciting phytoalexin production. Furthermore, we identified that brassilexin, the only commercially available phytoalexin that was detected in this study, demonstrated a MIC of 400 µg ml-1 against P. aeruginosa PA14. The production of phytoalexins can be an effective component of canola innate immunity to keep potential infections by the opportunistic pathogen P. aeruginosa at bay.
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Affiliation(s)
- Jamie Cook
- Department of Microbiology and Immunology, Dalhousie University, Halifax, Nova Scotia, Canada
| | - Joseph P M Hui
- Aquatic and Crop Resource Development Research Centre, National Research Council Canada, Halifax, Nova Scotia, Canada
| | - Janie Zhang
- Department of Microbiology and Immunology, Dalhousie University, Halifax, Nova Scotia, Canada
| | - Michaela Kember
- Department of Microbiology and Immunology, Dalhousie University, Halifax, Nova Scotia, Canada
| | - Fabrice Berrué
- Aquatic and Crop Resource Development Research Centre, National Research Council Canada, Halifax, Nova Scotia, Canada
| | - Junzeng Zhang
- Aquatic and Crop Resource Development Research Centre, National Research Council Canada, Halifax, Nova Scotia, Canada
| | - Zhenyu Cheng
- Department of Microbiology and Immunology, Dalhousie University, Halifax, Nova Scotia, Canada
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12
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Song S, Sun X, Guo Q, Cui B, Zhu Y, Li X, Zhou J, Zhang LH, Deng Y. An anthranilic acid-responsive transcriptional regulator controls the physiology and pathogenicity of Ralstonia solanacearum. PLoS Pathog 2022; 18:e1010562. [PMID: 35617422 PMCID: PMC9176790 DOI: 10.1371/journal.ppat.1010562] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2021] [Revised: 06/08/2022] [Accepted: 04/29/2022] [Indexed: 11/25/2022] Open
Abstract
Quorum sensing (QS) is widely employed by bacterial cells to control gene expression in a cell density-dependent manner. A previous study revealed that anthranilic acid from Ralstonia solanacearum plays a vital role in regulating the physiology and pathogenicity of R. solanacearum. We reported here that anthranilic acid controls the important biological functions and virulence of R. solanacearum through the receptor protein RaaR, which contains helix-turn-helix (HTH) and LysR substrate binding (LysR_substrate) domains. RaaR regulates the same processes as anthranilic acid, and both are present in various bacterial species. In addition, anthranilic acid-deficient mutant phenotypes were rescued by in trans expression of RaaR. Intriguingly, we found that anthranilic acid binds to the LysR_substrate domain of RaaR with high affinity, induces allosteric conformational changes, and then enhances the binding of RaaR to the promoter DNA regions of target genes. These findings indicate that the components of the anthranilic acid signaling system are distinguished from those of the typical QS systems. Together, our work presents a unique and widely conserved signaling system that might be an important new type of cell-to-cell communication system in bacteria. Bacterial wilt caused by Ralstonia solanacearum is one of the most widespread, harmful and destructive plant diseases in the world. Our previous study showed that the pathogenic bacterium R. solanacearum uses anthranilic acid to regulate the important biological functions, virulence and the production of quorum sensing signals. Here, we show that RaaR, a transcriptional regulator from R. solanacearum, was first identified to regulate the same phenotypes as anthranilic acid. Anthranilic acid binds to the LysR_substrate domain of RaaR and enhances the regulatory activity of RaaR to control the target gene expression, including the QS signal synthase encoding genes, phcB and solI. Both the anthranilic acid synthase TrpEG and the response regulator RaaR are present in diverse bacteria, suggesting that the anthranilic acid-type signaling system is widespread. Together, our work describes a system where a pathogen uses a single protein to control the bacterial physiology and pathogenesis by responding to anthranilic acid.
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Affiliation(s)
- Shihao Song
- School of Pharmaceutical Sciences (Shenzhen), Shenzhen Campus of Sun Yat-sen University, Sun Yat-sen University, Shenzhen, China
- Integrative Microbiology Research Center, College of Plant Protection, South China Agricultural University, Guangzhou, China
| | - Xiuyun Sun
- School of Pharmaceutical Sciences (Shenzhen), Shenzhen Campus of Sun Yat-sen University, Sun Yat-sen University, Shenzhen, China
| | - Quan Guo
- School of Pharmaceutical Sciences (Shenzhen), Shenzhen Campus of Sun Yat-sen University, Sun Yat-sen University, Shenzhen, China
| | - Binbin Cui
- School of Pharmaceutical Sciences (Shenzhen), Shenzhen Campus of Sun Yat-sen University, Sun Yat-sen University, Shenzhen, China
| | - Yu Zhu
- School of Pharmaceutical Sciences (Shenzhen), Shenzhen Campus of Sun Yat-sen University, Sun Yat-sen University, Shenzhen, China
| | - Xia Li
- School of Pharmaceutical Sciences (Shenzhen), Shenzhen Campus of Sun Yat-sen University, Sun Yat-sen University, Shenzhen, China
| | - Jianuan Zhou
- Integrative Microbiology Research Center, College of Plant Protection, South China Agricultural University, Guangzhou, China
| | - Lian-Hui Zhang
- Integrative Microbiology Research Center, College of Plant Protection, South China Agricultural University, Guangzhou, China
| | - Yinyue Deng
- School of Pharmaceutical Sciences (Shenzhen), Shenzhen Campus of Sun Yat-sen University, Sun Yat-sen University, Shenzhen, China
- * E-mail:
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13
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Transcriptome analysis of Pseudomonas aeruginosa biofilm infection in an ex vivo pig model of the cystic fibrosis lung. Appl Environ Microbiol 2021; 88:e0178921. [PMID: 34878811 PMCID: PMC8824274 DOI: 10.1128/aem.01789-21] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/04/2022] Open
Abstract
Pseudomonas aeruginosa is the predominant cause of chronic biofilm infections that form in the lungs of people with cystic fibrosis (CF). These infections are highly resistant to antibiotics and persist for years in the respiratory tract. One of the main research challenges is that current laboratory models do not accurately replicate key aspects of a P. aeruginosa biofilm infection, highlighted by previous RNA-sequencing studies. We compared the P. aeruginosa PA14 transcriptome in an ex vivo pig lung (EVPL) model of CF and a well-studied synthetic cystic fibrosis sputum medium (SCFM). P. aeruginosa was grown in the EVPL model for 1, 2, and 7 days, and in vitro in SCFM for 1 and 2 days. The RNA was extracted and sequenced at each time point. Our findings demonstrate that expression of antimicrobial resistance genes was cued by growth in the EVPL model, highlighting the importance of growth environment in determining accurate resistance profiles. The EVPL model created two distinct growth environments: tissue-associated biofilm and the SCFM surrounding tissue, each cuing a transcriptome distinct from that seen in SCFM in vitro. The expression of quorum sensing associated genes in the EVPL tissue-associated biofilm at 48 h relative to in vitro SCFM was similar to CF sputum versus in vitro conditions. Hence, the EVPL model can replicate key aspects of in vivo biofilm infection that are missing from other current models. It provides a more accurate P. aeruginosa growth environment for determining antimicrobial resistance that quickly drives P. aeruginosa into a chronic-like infection phenotype. IMPORTANCEPseudomonas aeruginosa lung infections that affect people with cystic fibrosis are resistant to most available antimicrobial treatments. The lack of a laboratory model that captures all key aspects of these infections hinders not only research progression but also clinical diagnostics. We used transcriptome analysis to demonstrate how a model using pig lungs can more accurately replicate key characteristics of P. aeruginosa lung infection, including mechanisms of antibiotic resistance and infection establishment. Therefore, this model may be used in the future to further understand infection dynamics to develop novel treatments and more accurate treatment plans. This could improve clinical outcomes as well as quality of life for individuals affected by these infections.
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14
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Michalet S, Allard PM, Commun C, Ngoc VTN, Nouwade K, Gioia B, Dijoux-Franca MG, Wolfender JL, Doléans-Jordheim A. Alkyl-Quinolones derivatives as potential biomarkers for Pseudomonas aeruginosa infection chronicity in Cystic Fibrosis. Sci Rep 2021; 11:20722. [PMID: 34671079 PMCID: PMC8528811 DOI: 10.1038/s41598-021-99467-7] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2021] [Accepted: 09/17/2021] [Indexed: 01/20/2023] Open
Abstract
In Cystic Fibrosis (CF), a rapid and standardized definition of chronic infection would allow a better management of Pseudomonas aeruginosa (Pa) infections, as well as a quick grouping of patients during clinical trials allowing better comparisons between studies. With this purpose, we compared the metabolic profiles of 44 in vitro cultures of Pa strains isolated from CF patients at different stages of infection in order to identify metabolites differentially synthetized according to these clinical stages. Compounds produced and secreted by each strain in the supernatant of a liquid culture were analysed by metabolomic approaches (UHPLC-DAD-ESI/QTOF, UV and UPLC-Orbitrap, MS). Multivariate analyses showed that first colonization strains could be differentiated from chronic colonization ones, by producing notably more Alkyl-Quinolones (AQs) derivatives. Especially, five AQs were discriminant: HQC5, HQNOC7, HQNOC7:1, db-PQS C9 and HQNOC9:1. However, the production of HHQ was equivalent between strain types. The HHQ/HQNOC9:1 ratio was then found to be significantly different between chronic and primo-colonising strains by using both UV (p = 0.003) and HRMS data (p = 1.5 × 10-5). Our study suggests that some AQ derivatives can be used as biomarkers for an improved management of CF patients as well as a better definition of the clinical stages of Pa infection.
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Affiliation(s)
- Serge Michalet
- grid.25697.3f0000 0001 2172 4233Université de Lyon, Lyon, France ,grid.7849.20000 0001 2150 7757Université Claude Bernard Lyon 1, Lyon, France ,grid.7849.20000 0001 2150 7757Research Group on Environmental Multiresistance and Bacterial Efflux, UMR CNRS 5557 Ecologie Microbienne, Université Claude Bernard Lyon 1, CNRS, VetAgro Sup, ISPB, Villeurbanne, France
| | - Pierre-Marie Allard
- grid.8591.50000 0001 2322 4988School of Pharmaceutical Sciences and Institute of Pharmaceutical Sciences of Western Switzerland, University of Geneva, CMU, Rue Michel-Servet 1, 1211 Geneve 4, Switzerland
| | - Carine Commun
- grid.25697.3f0000 0001 2172 4233Université de Lyon, Lyon, France ,grid.7849.20000 0001 2150 7757Université Claude Bernard Lyon 1, Lyon, France ,grid.7849.20000 0001 2150 7757Research Group on Bacterial Opportunistic Pathogens and Environment, UMR CNRS 5557 Ecologie Microbienne, Université Claude Bernard Lyon 1, CNRS, VetAgro Sup, ISPB, Villeurbanne, France
| | - Van Thanh Nguyen Ngoc
- grid.25697.3f0000 0001 2172 4233Université de Lyon, Lyon, France ,grid.7849.20000 0001 2150 7757Université Claude Bernard Lyon 1, Lyon, France ,grid.7849.20000 0001 2150 7757Research Group on Environmental Multiresistance and Bacterial Efflux, UMR CNRS 5557 Ecologie Microbienne, Université Claude Bernard Lyon 1, CNRS, VetAgro Sup, ISPB, Villeurbanne, France
| | - Kodjo Nouwade
- grid.25697.3f0000 0001 2172 4233Université de Lyon, Lyon, France ,grid.7849.20000 0001 2150 7757Université Claude Bernard Lyon 1, Lyon, France ,grid.7849.20000 0001 2150 7757Research Group on Environmental Multiresistance and Bacterial Efflux, UMR CNRS 5557 Ecologie Microbienne, Université Claude Bernard Lyon 1, CNRS, VetAgro Sup, ISPB, Villeurbanne, France
| | - Bruna Gioia
- grid.25697.3f0000 0001 2172 4233Université de Lyon, Lyon, France ,grid.7849.20000 0001 2150 7757Université Claude Bernard Lyon 1, Lyon, France ,EA 4446, Molécules bioactives et chimie médicinale (B2MC), ISPB-Faculté de Pharmacie, Lyon, France
| | - Marie-Geneviève Dijoux-Franca
- grid.25697.3f0000 0001 2172 4233Université de Lyon, Lyon, France ,grid.7849.20000 0001 2150 7757Université Claude Bernard Lyon 1, Lyon, France ,grid.7849.20000 0001 2150 7757Research Group on Environmental Multiresistance and Bacterial Efflux, UMR CNRS 5557 Ecologie Microbienne, Université Claude Bernard Lyon 1, CNRS, VetAgro Sup, ISPB, Villeurbanne, France
| | - Jean-Luc Wolfender
- grid.8591.50000 0001 2322 4988School of Pharmaceutical Sciences and Institute of Pharmaceutical Sciences of Western Switzerland, University of Geneva, CMU, Rue Michel-Servet 1, 1211 Geneve 4, Switzerland
| | - Anne Doléans-Jordheim
- grid.25697.3f0000 0001 2172 4233Université de Lyon, Lyon, France ,grid.7849.20000 0001 2150 7757Université Claude Bernard Lyon 1, Lyon, France ,grid.7849.20000 0001 2150 7757Research Group on Bacterial Opportunistic Pathogens and Environment, UMR CNRS 5557 Ecologie Microbienne, Université Claude Bernard Lyon 1, CNRS, VetAgro Sup, ISPB, Villeurbanne, France ,grid.413852.90000 0001 2163 3825Laboratoire de Bactériologie, Institut des Agents Infectieux, Hospices Civils de Lyon, Lyon, France
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15
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Soh EYC, Smith F, Gimenez MR, Yang L, Vejborg RM, Fletcher M, Halliday N, Bleves S, Heeb S, Cámara M, Givskov M, Hardie KR, Tolker-Nielsen T, Ize B, Williams P. Disruption of the Pseudomonas aeruginosa Tat system perturbs PQS-dependent quorum sensing and biofilm maturation through lack of the Rieske cytochrome bc1 sub-unit. PLoS Pathog 2021; 17:e1009425. [PMID: 34460871 PMCID: PMC8432897 DOI: 10.1371/journal.ppat.1009425] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2021] [Revised: 09/10/2021] [Accepted: 08/10/2021] [Indexed: 11/18/2022] Open
Abstract
Extracellular DNA (eDNA) is a major constituent of the extracellular matrix of Pseudomonas aeruginosa biofilms and its release is regulated via pseudomonas quinolone signal (PQS) dependent quorum sensing (QS). By screening a P. aeruginosa transposon library to identify factors required for DNA release, mutants with insertions in the twin-arginine translocation (Tat) pathway were identified as exhibiting reduced eDNA release, and defective biofilm architecture with enhanced susceptibility to tobramycin. P. aeruginosa tat mutants showed substantial reductions in pyocyanin, rhamnolipid and membrane vesicle (MV) production consistent with perturbation of PQS-dependent QS as demonstrated by changes in pqsA expression and 2-alkyl-4-quinolone (AQ) production. Provision of exogenous PQS to the tat mutants did not return pqsA, rhlA or phzA1 expression or pyocyanin production to wild type levels. However, transformation of the tat mutants with the AQ-independent pqs effector pqsE restored phzA1 expression and pyocyanin production. Since mutation or inhibition of Tat prevented PQS-driven auto-induction, we sought to identify the Tat substrate(s) responsible. A pqsA::lux fusion was introduced into each of 34 validated P. aeruginosa Tat substrate deletion mutants. Analysis of each mutant for reduced bioluminescence revealed that the primary signalling defect was associated with the Rieske iron-sulfur subunit of the cytochrome bc1 complex. In common with the parent strain, a Rieske mutant exhibited defective PQS signalling, AQ production, rhlA expression and eDNA release that could be restored by genetic complementation. This defect was also phenocopied by deletion of cytB or cytC1. Thus, either lack of the Rieske sub-unit or mutation of cytochrome bc1 genes results in the perturbation of PQS-dependent autoinduction resulting in eDNA deficient biofilms, reduced antibiotic tolerance and compromised virulence factor production. Pseudomonas aeruginosa is a highly adaptable human pathogen responsible for causing chronic biofilm-associated infections. Biofilms are highly refractory to host defences and antibiotics and thus difficult to eradicate. The biofilm extracellular matrix incorporates extracellular DNA (eDNA). This stabilizes biofilm architecture and helps confer tolerance to antibiotics. Since mechanisms that control eDNA release are not well understood, we screened a P. aeruginosa mutant bank for strains with defects in eDNA release and discovered a role for the twin-arginine translocation (Tat) pathway that exports folded proteins across the cytoplasmic membrane. Perturbation of the Tat pathway resulted in defective biofilms susceptible to antibiotic treatment as a consequence of perturbed pseudomonas quinolone (PQS) signalling. This resulted in the failure to produce or release biofilm components including eDNA, phenazines and rhamnolipids as well as microvesicles. Furthermore, we discovered that perturbation of PQS signalling was a consequence of the inability of tat mutants to translocate the Rieske subunit of the cytochrome bc1 complex involved in electron transfer and energy transduction. Given the importance of PQS signalling and the Tat system to virulence and biofilm maturation in P. aeruginosa, our findings underline the potential of the Tat system as a drug target for novel antimicrobial agents.
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Affiliation(s)
- Eliza Ye-Chen Soh
- Biodiscovery Institute, National Biofilms Innovation Centre and School of Life Sciences, University of Nottingham, Nottingham, United Kingdom
| | - Frances Smith
- Biodiscovery Institute, National Biofilms Innovation Centre and School of Life Sciences, University of Nottingham, Nottingham, United Kingdom
| | - Maxime Rémi Gimenez
- Laboratoire d’Ingénierie des Systèmes Macromoléculaires (LISM-UMR7255), Institut de Microbiologie de la Méditerranée, CNRS and Aix-Marseille University, Marseille, France
| | - Liang Yang
- Singapore Centre for Environmental Life Sciences Engineering, Nanyang Technological University, Singapore
| | - Rebecca Munk Vejborg
- Costerton Biofilm Center, Department of Immunology and Microbiology, Faculty of Health Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Matthew Fletcher
- Biodiscovery Institute, National Biofilms Innovation Centre and School of Life Sciences, University of Nottingham, Nottingham, United Kingdom
| | - Nigel Halliday
- Biodiscovery Institute, National Biofilms Innovation Centre and School of Life Sciences, University of Nottingham, Nottingham, United Kingdom
| | - Sophie Bleves
- Laboratoire d’Ingénierie des Systèmes Macromoléculaires (LISM-UMR7255), Institut de Microbiologie de la Méditerranée, CNRS and Aix-Marseille University, Marseille, France
| | - Stephan Heeb
- Biodiscovery Institute, National Biofilms Innovation Centre and School of Life Sciences, University of Nottingham, Nottingham, United Kingdom
| | - Miguel Cámara
- Biodiscovery Institute, National Biofilms Innovation Centre and School of Life Sciences, University of Nottingham, Nottingham, United Kingdom
| | - Michael Givskov
- Singapore Centre for Environmental Life Sciences Engineering, Nanyang Technological University, Singapore
- Costerton Biofilm Center, Department of Immunology and Microbiology, Faculty of Health Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Kim R. Hardie
- Biodiscovery Institute, National Biofilms Innovation Centre and School of Life Sciences, University of Nottingham, Nottingham, United Kingdom
| | - Tim Tolker-Nielsen
- Costerton Biofilm Center, Department of Immunology and Microbiology, Faculty of Health Sciences, University of Copenhagen, Copenhagen, Denmark
- * E-mail: (TT-N); (BI); (PW)
| | - Bérengère Ize
- Laboratoire d’Ingénierie des Systèmes Macromoléculaires (LISM-UMR7255), Institut de Microbiologie de la Méditerranée, CNRS and Aix-Marseille University, Marseille, France
- * E-mail: (TT-N); (BI); (PW)
| | - Paul Williams
- Biodiscovery Institute, National Biofilms Innovation Centre and School of Life Sciences, University of Nottingham, Nottingham, United Kingdom
- * E-mail: (TT-N); (BI); (PW)
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16
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Biological and clinical significance of quorum sensing alkylquinolones: current analytical and bioanalytical methods for their quantification. Anal Bioanal Chem 2021; 413:4599-4618. [PMID: 33959788 DOI: 10.1007/s00216-021-03356-x] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2021] [Revised: 03/21/2021] [Accepted: 04/16/2021] [Indexed: 12/27/2022]
Abstract
Quorum sensing (QS) is a sophisticated bacterial communication system which plays a key role in the virulence and biofilm formation of many pathogens. The Pseudomonas aeruginosa QS network consists of four sets of connected systems (las, rlh, pqs and iqs) hierarchically organized. The pqs system involves characteristic autoinducers (AI), most of them sharing an alkylquinolone (AQ) structure, and is able to carry out several relevant biological functions besides its main signalling activity. Their role in bacterial physiology and pathogenicity has been widely studied. Indeed, the presence of these metabolites in several body fluids and infected tissues has pointed to their potential value as biomarkers of infection. In this review, we summarize the most recent findings about the biological implications and the clinical significance of the main P. aeruginosa AQs. These findings have encouraged the development of analytical and bioanalytical techniques addressed to assess the role of these metabolites in bacterial growth and survival, during pathogenesis or as biomarkers of infections. The availability of highly sensitive reliable analytical methods suitable for clinical analysis would allow getting knowledge about pathogenesis and disease prognosis or progression, supporting clinicians on the decision-making process for the management of these infections and guiding them on the application of more effective and appropriate treatments. The benefits from the implementation of the point-of-care (PoC)-type testing in infectious disease diagnostics, which are seen to improve patient outcomes by promoting earlier therapeutic interventions, are also discussed.
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17
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Baldelli V, D'Angelo F, Pavoncello V, Fiscarelli EV, Visca P, Rampioni G, Leoni L. Identification of FDA-approved antivirulence drugs targeting the Pseudomonas aeruginosa quorum sensing effector protein PqsE. Virulence 2021; 11:652-668. [PMID: 32423284 PMCID: PMC7549961 DOI: 10.1080/21505594.2020.1770508] [Citation(s) in RCA: 26] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
The ability of the bacterial pathogen Pseudomonas aeruginosa to cause both chronic and acute infections mainly relies on its capacity to finely modulate the expression of virulence factors through a complex network of regulatory circuits, including the pqs quorum sensing (QS) system. While in most QS systems the signal molecule/receptor complexes act as global regulators that modulate the expression of QS-controlled genes, the main effector protein of the pqs system is PqsE. This protein is involved in the synthesis of the QS signal molecules 2-alkyl-4(1H)-quinolones (AQs), but it also modulates the expression of genes involved in virulence factors production and biofilm formation via AQ-independent pathway(s). P. aeruginosa pqsE mutants disclose attenuated virulence in plant and animal infection models, hence PqsE is considered a good target for the development of antivirulence drugs against P. aeruginosa. In this study, the negative regulation exerted by PqsE on its own transcription has been exploited to develop a screening system for the identification of PqsE inhibitors in a library of FDA-approved drugs. This led to the identification of nitrofurazone and erythromycin estolate, two antibiotic compounds that reduce the expression of PqsE-dependent virulence traits and biofilm formation in the model strain P. aeruginosa PAO1 at concentrations far below those affecting the bacterial growth rate. Notably, both drugs reduce the production of the PqsE-controlled virulence factor pyocyanin also in P. aeruginosa strains isolated from cystic fibrosis patients, and do not antagonize the activity of antibiotics commonly used to treat P. aeruginosa infection.
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Affiliation(s)
| | | | | | | | - Paolo Visca
- Department of Science, University Roma Tre , Rome, Italy
| | | | - Livia Leoni
- Department of Science, University Roma Tre , Rome, Italy
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18
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Paulsen SS, Isbrandt T, Kirkegaard M, Buijs Y, Strube ML, Sonnenschein EC, Larsen TO, Gram L. Production of the antimicrobial compound tetrabromopyrrole and the Pseudomonas quinolone system precursor, 2-heptyl-4-quinolone, by a novel marine species Pseudoalteromonas galatheae sp. nov. Sci Rep 2020; 10:21630. [PMID: 33303891 PMCID: PMC7730127 DOI: 10.1038/s41598-020-78439-3] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2019] [Accepted: 11/25/2020] [Indexed: 01/23/2023] Open
Abstract
Novel antimicrobials are urgently needed due to the rapid spread of antibiotic resistant bacteria. In a genome-wide analysis of Pseudoalteromonas strains, one strain (S4498) was noticed due to its potent antibiotic activity. It did not produce the yellow antimicrobial pigment bromoalterochromide, which was produced by several related type strains with which it shared less than 95% average nucleotide identity. Also, it produced a sweet-smelling volatile not observed from other strains. Mining the genome of strain S4498 using the secondary metabolite prediction tool antiSMASH led to eight biosynthetic gene clusters with no homology to known compounds, and synteny analyses revealed that the yellow pigment bromoalterochromide was likely lost during evolution. Metabolome profiling of strain S4498 using HPLC-HRMS analyses revealed marked differences to the type strains. In particular, a series of quinolones known as pseudanes were identified and verified by NMR. The characteristic odor of the strain was linked to the pseudanes. The highly halogenated compound tetrabromopyrrole was detected as the major antibacterial component by bioassay-guided fractionation. Taken together, the polyphasic analysis demonstrates that strain S4498 belongs to a novel species within the genus Pseudoalteromonas, and we propose the name Pseudoalteromonas galatheae sp. nov. (type strain S4498T = NCIMB 15250T = LMG 31599T).
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Affiliation(s)
- Sara Skøtt Paulsen
- Department of Biotechnology and Biomedicine, Technical University of Denmark, Søltofts Plads 221, 2800, Kgs. Lyngby, Denmark
| | - Thomas Isbrandt
- Department of Biotechnology and Biomedicine, Technical University of Denmark, Søltofts Plads 221, 2800, Kgs. Lyngby, Denmark
| | - Markus Kirkegaard
- Department of Biotechnology and Biomedicine, Technical University of Denmark, Søltofts Plads 221, 2800, Kgs. Lyngby, Denmark
| | - Yannick Buijs
- Department of Biotechnology and Biomedicine, Technical University of Denmark, Søltofts Plads 221, 2800, Kgs. Lyngby, Denmark
| | - Mikael Lenz Strube
- Department of Biotechnology and Biomedicine, Technical University of Denmark, Søltofts Plads 221, 2800, Kgs. Lyngby, Denmark
| | - Eva C Sonnenschein
- Department of Biotechnology and Biomedicine, Technical University of Denmark, Søltofts Plads 221, 2800, Kgs. Lyngby, Denmark
| | - Thomas O Larsen
- Department of Biotechnology and Biomedicine, Technical University of Denmark, Søltofts Plads 221, 2800, Kgs. Lyngby, Denmark
| | - Lone Gram
- Department of Biotechnology and Biomedicine, Technical University of Denmark, Søltofts Plads 221, 2800, Kgs. Lyngby, Denmark.
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19
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Ramos AF, Woods DF, Shanahan R, Cano R, McGlacken GP, Serra C, O'Gara F, Reen FJ. A structure-function analysis of interspecies antagonism by the 2-heptyl-4-alkyl-quinolone signal molecule from Pseudomonas aeruginosa. MICROBIOLOGY-SGM 2020; 166:169-179. [PMID: 31860435 DOI: 10.1099/mic.0.000876] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
In recent years, the alkyl-quinolone molecular framework has already provided a rich source of bioactivity for the development of novel anti-infective compounds. Based on the quorum-sensing signalling molecules 4-hydroxy-2-heptylquinoline (HHQ) and 3,4-dihydroxy-2-heptylquinoline (PQS) from the nosocomial pathogen Pseudomonas aeruginosa, modifications have been developed with markedly enhanced anti-biofilm bioactivity towards important fungal and bacterial pathogens, including Candida albicans and Aspergillus fumigatus. Here we show that antibacterial activity of HHQ against Vibrionaceae is species-specific and it requires an exquisite level of structural fidelity within the alkyl-quinolone molecular framework. Antibacterial activity was demonstrated against the serious human pathogens Vibrio vulnificus and Vibrio cholerae as well as a panel of bioluminescent squid symbiont Allivibrio fischeri isolates. In contrast, Vibrio parahaemolyticus growth and biofilm formation was unaffected in the presence of HHQ and all the structural variants tested. In general, modification to almost all of the molecule except the alkyl-chain end, led to loss of activity. This suggests that the bacteriostatic activity of HHQ requires the concerted action of the entire framework components. The only exception to this pattern was deuteration of HHQ at the C3 position. HHQ modified with a terminal alkene at the quinolone alkyl chain retained bacteriostatic activity and was also found to activate PqsR signalling comparable to the native agonist. The data from this integrated analysis provides novel insights into the structural flexibility underpinning the signalling activity of the complex alkyl-quinolone molecular communication system.
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Affiliation(s)
- Ana F Ramos
- CIIMAR, -Centro Interdisciplinar de Investigação Marinha e Ambiental University of Porto, Porto Matosinhos, Portugal.,Departamento de Biologia, Faculdade de Ciências, Universidade do Porto, Porto, Portugal
| | - David F Woods
- BIOMERIT Research Centre, School of Microbiology, University College Cork, Cork, Ireland
| | - Rachel Shanahan
- School of Chemistry and Analytical and Biological Chemistry Research Facility, University College Cork, Cork, Ireland
| | - Rafael Cano
- School of Chemistry and Analytical and Biological Chemistry Research Facility, University College Cork, Cork, Ireland
| | - Gerard P McGlacken
- SSPC, Synthesis and Solid State Pharmaceutical Centre, Ireland.,School of Chemistry and Analytical and Biological Chemistry Research Facility, University College Cork, Cork, Ireland
| | - Claudia Serra
- CIIMAR, -Centro Interdisciplinar de Investigação Marinha e Ambiental University of Porto, Porto Matosinhos, Portugal
| | - Fergal O'Gara
- BIOMERIT Research Centre, School of Microbiology, University College Cork, Cork, Ireland.,Telethon Kids Institute, Perth Children's Hospital, PerthWA 6009, Australia.,SSPC, Synthesis and Solid State Pharmaceutical Centre, Ireland.,School of Pharmacy and Biomedical Sciences, Curtin Health Innovation Research Institute, Curtin University, PerthWA, Australia
| | - F Jerry Reen
- School of Microbiology, University College Cork, Cork, Ireland
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20
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Bacterial Alkyl-4-quinolones: Discovery, Structural Diversity and Biological Properties. Molecules 2020; 25:molecules25235689. [PMID: 33276615 PMCID: PMC7731028 DOI: 10.3390/molecules25235689] [Citation(s) in RCA: 25] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2020] [Revised: 11/27/2020] [Accepted: 11/27/2020] [Indexed: 11/17/2022] Open
Abstract
The alkyl-4-quinolones (AQs) are a class of metabolites produced primarily by members of the Pseudomonas and Burkholderia genera, consisting of a 4-quinolone core substituted by a range of pendant groups, most commonly at the C-2 position. The history of this class of compounds dates back to the 1940s, when a range of alkylquinolones with notable antibiotic properties were first isolated from Pseudomonas aeruginosa. More recently, it was discovered that an alkylquinolone derivative, the Pseudomonas Quinolone Signal (PQS) plays a key role in bacterial communication and quorum sensing in Pseudomonas aeruginosa. Many of the best-studied examples contain simple hydrocarbon side-chains, but more recent studies have revealed a wide range of structurally diverse examples from multiple bacterial genera, including those with aromatic, isoprenoid, or sulfur-containing side-chains. In addition to their well-known antimicrobial properties, alkylquinolones have been reported with antimalarial, antifungal, antialgal, and antioxidant properties. Here we review the structural diversity and biological activity of these intriguing metabolites.
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21
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Cooke AC, Florez C, Dunshee EB, Lieber AD, Terry ML, Light CJ, Schertzer JW. Pseudomonas Quinolone Signal-Induced Outer Membrane Vesicles Enhance Biofilm Dispersion in Pseudomonas aeruginosa. mSphere 2020; 5:e01109-20. [PMID: 33239369 PMCID: PMC7690959 DOI: 10.1128/msphere.01109-20] [Citation(s) in RCA: 41] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2020] [Accepted: 11/08/2020] [Indexed: 01/15/2023] Open
Abstract
Bacterial biofilms are major contributors to chronic infections in humans. Because they are recalcitrant to conventional therapy, they present a particularly difficult treatment challenge. Identifying factors involved in biofilm development can help uncover novel targets and guide the development of antibiofilm strategies. Pseudomonas aeruginosa causes surgical site, burn wound, and hospital-acquired infections and is also associated with aggressive biofilm formation in the lungs of cystic fibrosis patients. A potent but poorly understood contributor to P. aeruginosa virulence is the ability to produce outer membrane vesicles (OMVs). OMV trafficking has been associated with cell-cell communication, virulence factor delivery, and transfer of antibiotic resistance genes. Because OMVs have almost exclusively been studied using planktonic cultures, little is known about their biogenesis and function in biofilms. Several groups have shown that Pseudomonas quinolone signal (PQS) induces OMV formation in P. aeruginosa Our group described a biophysical mechanism for this and recently showed it is operative in biofilms. Here, we demonstrate that PQS-induced OMV production is highly dynamic during biofilm development. Interestingly, PQS and OMV synthesis are significantly elevated during dispersion compared to attachment and maturation stages. PQS biosynthetic and receptor mutant biofilms were significantly impaired in their ability to disperse, but this phenotype was rescued by genetic complementation or exogenous addition of PQS. Finally, we show that purified OMVs can actively degrade extracellular protein, lipid, and DNA. We therefore propose that enhanced production of PQS-induced OMVs during biofilm dispersion facilitates cell escape by coordinating the controlled degradation of biofilm matrix components.IMPORTANCE Treatments that manipulate biofilm dispersion hold the potential to convert chronic drug-tolerant biofilm infections from protected sessile communities into released populations that are orders-of-magnitude more susceptible to antimicrobial treatment. However, dispersed cells often exhibit increased acute virulence and dissemination phenotypes. A thorough understanding of the dispersion process is therefore critical before this promising strategy can be effectively employed. Pseudomonas quinolone signal (PQS) has been implicated in early biofilm development, but we hypothesized that its function as an outer membrane vesicle (OMV) inducer may contribute at multiple stages. Here, we demonstrate that PQS and OMVs are differentially produced during Pseudomonas aeruginosa biofilm development and provide evidence that effective biofilm dispersion is dependent on the production of PQS-induced OMVs, which likely act as delivery vehicles for matrix-degrading enzymes. These findings lay the groundwork for understanding OMV contributions to biofilm development and suggest a model to explain the controlled matrix degradation that accompanies biofilm dispersion in many species.
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Affiliation(s)
- Adam C Cooke
- Department of Biological Sciences, Binghamton University, Binghamton, New York, USA
- Binghamton Biofilm Research Center, Binghamton University, Binghamton, New York, USA
| | - Catalina Florez
- Department of Biological Sciences, Binghamton University, Binghamton, New York, USA
- Binghamton Biofilm Research Center, Binghamton University, Binghamton, New York, USA
| | - Elise B Dunshee
- Department of Biological Sciences, Binghamton University, Binghamton, New York, USA
- Binghamton Biofilm Research Center, Binghamton University, Binghamton, New York, USA
| | - Avery D Lieber
- Department of Biological Sciences, Binghamton University, Binghamton, New York, USA
- First-year Research Immersion Program, Binghamton University, Binghamton, New York, USA
| | - Michelle L Terry
- Department of Biological Sciences, Binghamton University, Binghamton, New York, USA
- First-year Research Immersion Program, Binghamton University, Binghamton, New York, USA
| | - Caitlin J Light
- Department of Biological Sciences, Binghamton University, Binghamton, New York, USA
- Binghamton Biofilm Research Center, Binghamton University, Binghamton, New York, USA
- First-year Research Immersion Program, Binghamton University, Binghamton, New York, USA
- Summer Research Immersion Program, Binghamton University, Binghamton, New York, USA
| | - Jeffrey W Schertzer
- Department of Biological Sciences, Binghamton University, Binghamton, New York, USA
- Binghamton Biofilm Research Center, Binghamton University, Binghamton, New York, USA
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22
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Secondary metabolites from the Burkholderia pseudomallei complex: structure, ecology, and evolution. J Ind Microbiol Biotechnol 2020; 47:877-887. [PMID: 33052546 DOI: 10.1007/s10295-020-02317-0] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2020] [Accepted: 09/22/2020] [Indexed: 12/15/2022]
Abstract
Bacterial secondary metabolites play important roles in promoting survival, though few have been carefully studied in their natural context. Numerous gene clusters code for secondary metabolites in the genomes of members of the Bptm group, made up of three closely related species with distinctly different lifestyles: the opportunistic pathogen Burkholderia pseudomallei, the non-pathogenic saprophyte Burkholderia thailandensis, and the host-adapted pathogen Burkholderia mallei. Several biosynthetic gene clusters are conserved across two or all three species, and this provides an opportunity to understand how the corresponding secondary metabolites contribute to survival in different contexts in nature. In this review, we discuss three secondary metabolites from the Bptm group: bactobolin, malleilactone (and malleicyprol), and the 4-hydroxy-3-methyl-2-alkylquinolines, providing an overview of each of their biosynthetic pathways and insight into their potential ecological roles. Results of studies on these secondary metabolites provide a window into how secondary metabolites contribute to bacterial survival in different environments, from host infections to polymicrobial soil communities.
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23
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Alcalde-Rico M, Olivares-Pacheco J, Halliday N, Cámara M, Martínez JL. The impaired quorum sensing response of Pseudomonas aeruginosa MexAB-OprM efflux pump overexpressing mutants is not due to non-physiological efflux of 3-oxo-C12-HSL. Environ Microbiol 2020; 22:5167-5188. [PMID: 32715566 DOI: 10.1111/1462-2920.15177] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2020] [Revised: 06/18/2020] [Accepted: 07/24/2020] [Indexed: 11/29/2022]
Abstract
Multidrug (MDR) efflux pumps are ancient and conserved molecular machineries with relevant roles in different aspects of the bacterial physiology, besides antibiotic resistance. In the case of the environmental opportunistic pathogen Pseudomonas aeruginosa, it has been shown that overexpression of different efflux pumps is linked to the impairment of the quorum sensing (QS) response. Nevertheless, the causes of such impairment are different for each analysed efflux pump. Herein, we performed an in-depth analysis of the QS-mediated response of a P. aeruginosa antibiotic resistant mutant that overexpresses MexAB-OprM. Although previous work claimed that this efflux pump extrudes the QS signal 3-oxo-C12-HSL, we show otherwise. Our results evidence that the observed attenuation in the QS response when overexpressing this pump is related to an impaired production of alkyl quinolone QS signals, likely prompted by the reduced availability of one of their precursors, the octanoate. Together with previous studies, this indicates that, although the consequences of overexpressing efflux pumps are similar (impaired QS response), the underlying mechanisms are different. This 'apparent redundancy' of MDR efflux systems can be understood as a P. aeruginosa strategy to keep the robustness of the QS regulatory network and modulate its output in response to different signals.
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Affiliation(s)
- Manuel Alcalde-Rico
- Centro Nacional de Biotecnología, CSIC, Madrid, 28049, Spain.,Grupo de Resistencia Antimicrobiana en Bacterias Patógenas y Ambientales GRABPA, Instituto de Biología, Facultad de Ciencias, Pontificia Universidad Católica de Valparaíso, Valparaiso, 2340025, Chile.,Millennium Nucleus for Collaborative Research on Bacterial Resistance (MICROB-R), Santiago, Chile
| | - Jorge Olivares-Pacheco
- Grupo de Resistencia Antimicrobiana en Bacterias Patógenas y Ambientales GRABPA, Instituto de Biología, Facultad de Ciencias, Pontificia Universidad Católica de Valparaíso, Valparaiso, 2340025, Chile.,Millennium Nucleus for Collaborative Research on Bacterial Resistance (MICROB-R), Santiago, Chile
| | - Nigel Halliday
- National Biofilms Innovation Centre, Nottingham University Biodiscovery Institute, School of Life Sciences, University of Nottingham, Nottingham, UK
| | - Miguel Cámara
- National Biofilms Innovation Centre, Nottingham University Biodiscovery Institute, School of Life Sciences, University of Nottingham, Nottingham, UK
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24
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Song S, Yin W, Sun X, Cui B, Huang L, Li P, Yang L, Zhou J, Deng Y. Anthranilic acid from Ralstonia solanacearum plays dual roles in intraspecies signalling and inter-kingdom communication. THE ISME JOURNAL 2020; 14:2248-2260. [PMID: 32457502 PMCID: PMC7608240 DOI: 10.1038/s41396-020-0682-7] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/11/2019] [Revised: 05/02/2020] [Accepted: 05/07/2020] [Indexed: 11/25/2022]
Abstract
Quorum sensing (QS) signals are widely utilized by bacteria to regulate biological functions in response to cell population density. Previous studies have demonstrated that Ralstonia solanacearum employs two different types of QS systems. We report here that anthranilic acid controls important biological functions and the production of QS signals in R. solanacearum. It was demonstrated that the biosynthesis of anthranilic acid is mainly performed by TrpEG. The accumulation of anthranilic acid and the transcription of trpEG occur in a cell density-dependent manner in R. solanacearum. Both the anthranilic acid and TrpEG homologues are conserved in various bacterial species. Moreover, we show that Sporisorium scitamineum sexual mating and hypha formation are strongly inhibited by the addition of exogenous anthranilic acid. Our results suggest that anthranilic acid is important for the physiology of bacteria in addition to its role in inter-kingdom communication.
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Affiliation(s)
- Shihao Song
- College of Agriculture, South China Agricultural University, Guangzhou, 510642, China
- School of Pharmaceutical Sciences (Shenzhen), Sun Yat-sen University, Guangzhou, 510275, China
| | - Wenfang Yin
- College of Agriculture, South China Agricultural University, Guangzhou, 510642, China
| | - Xiuyun Sun
- College of Agriculture, South China Agricultural University, Guangzhou, 510642, China
- School of Pharmaceutical Sciences (Shenzhen), Sun Yat-sen University, Guangzhou, 510275, China
| | - Binbin Cui
- School of Pharmaceutical Sciences (Shenzhen), Sun Yat-sen University, Guangzhou, 510275, China
| | - Lei Huang
- School of Pharmaceutical Sciences (Shenzhen), Sun Yat-sen University, Guangzhou, 510275, China
| | - Peng Li
- Ministry of Education Key Laboratory for Ecology of Tropical Islands, College of Life Sciences, Hainan Normal University, Haikou, 571158, China
| | - Liang Yang
- School of Medicine, Southern University of Science and Technology, Shenzhen, 518055, China
| | - Jianuan Zhou
- College of Agriculture, South China Agricultural University, Guangzhou, 510642, China
| | - Yinyue Deng
- School of Pharmaceutical Sciences (Shenzhen), Sun Yat-sen University, Guangzhou, 510275, China.
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25
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Li J, Sun W, Saalim M, Wei G, Zaleta-Pinet DA, Clark BR. Isolation of 2-Alkyl-4-quinolones with Unusual Side Chains from a Chinese Pseudomonas aeruginosa Isolate. JOURNAL OF NATURAL PRODUCTS 2020; 83:2294-2298. [PMID: 32603106 DOI: 10.1021/acs.jnatprod.0c00026] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
Chemical investigation of a Pseudomonas aeruginosa strain isolated from Hebei, China, led to the isolation of a suite of quinolones, quinolone-N-oxides, and phenazines, the structures of which were elucidated by detailed spectroscopic analysis. Most notable among the secondary metabolites isolated was an unprecedented 4-quinolone containing an S-methyl group in the side chain and a new derivative including a phenyl ring in the side chain, which expand significantly the variety of structural motifs found in the quinolones and raise interesting questions about their biosynthesis.
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Affiliation(s)
- Jianye Li
- School of Pharmaceutical Science and Technology, Tianjin University, 92 Weijin Road, Tianjin 300092, People's Republic of China
| | - Weiwei Sun
- School of Pharmaceutical Science and Technology, Tianjin University, 92 Weijin Road, Tianjin 300092, People's Republic of China
| | - Muhammad Saalim
- School of Pharmaceutical Science and Technology, Tianjin University, 92 Weijin Road, Tianjin 300092, People's Republic of China
| | - Guixiang Wei
- School of Pharmaceutical Science and Technology, Tianjin University, 92 Weijin Road, Tianjin 300092, People's Republic of China
| | - Diana A Zaleta-Pinet
- School of Pharmaceutical Science and Technology, Tianjin University, 92 Weijin Road, Tianjin 300092, People's Republic of China
| | - Benjamin R Clark
- School of Pharmaceutical Science and Technology, Tianjin University, 92 Weijin Road, Tianjin 300092, People's Republic of China
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26
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Spatiotemporal Distribution of Pseudomonas aeruginosa Alkyl Quinolones under Metabolic and Competitive Stress. mSphere 2020; 5:5/4/e00426-20. [PMID: 32699119 PMCID: PMC7376503 DOI: 10.1128/msphere.00426-20] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023] Open
Abstract
Alkyl quinolones (AQs), including Pseudomonas quinolone signal (PQS), made by the opportunistic pathogen Pseudomonas aeruginosa have been associated with both population density and stress. The regulation of AQ production is known to be complex, and the stimuli that modulate AQ responses are not fully clear. Here, we have used hyperspectral Raman chemical imaging to examine the temporal and spatial profiles of AQs exhibited by P. aeruginosa under several potentially stressful conditions. We found that metabolic stress, effected by carbon limitation, or competition stress, effected by proximity to other species, resulted in accelerated PQS production. This competition effect did not require cell-to-cell interaction, as evidenced by the fact that the addition of supernatants from either Escherichia coli or Staphylococcus aureus led to early appearance of PQS. Lastly, the fact that these modulations were observed for PQS but not for all AQs suggests a high level of complexity in AQ regulation that remains to be discerned. Pseudomonas aeruginosa is an opportunistic human pathogen important to diseases such as cystic fibrosis. P. aeruginosa has multiple quorum-sensing (QS) systems, one of which utilizes the signaling molecule 2-heptyl-3-hydroxy-4-quinolone (Pseudomonas quinolone signal [PQS]). Here, we use hyperspectral Raman imaging to elucidate the spatiotemporal PQS distributions that determine how P. aeruginosa regulates surface colonization and its response to both metabolic stress and competition from other bacterial strains. These chemical imaging experiments illustrate the strong link between environmental challenges, such as metabolic stress caused by nutritional limitations or the presence of another bacterial species, and PQS signaling. Metabolic stress elicits a complex response in which limited nutrients induce the bacteria to produce PQS earlier, but the bacteria may also pause PQS production entirely if the nutrient concentration is too low. Separately, coculturing P. aeruginosa in the proximity of another bacterial species, or its culture supernatant, results in earlier production of PQS. However, these differences in PQS appearance are not observed for all alkyl quinolones (AQs) measured; the spatiotemporal response of 2-heptyl-4-hydroxyquinoline N-oxide (HQNO) is highly uniform for most conditions. These insights on the spatiotemporal distributions of quinolones provide additional perspective on the behavior of P. aeruginosa in response to different environmental cues. IMPORTANCE Alkyl quinolones (AQs), including Pseudomonas quinolone signal (PQS), made by the opportunistic pathogen Pseudomonas aeruginosa have been associated with both population density and stress. The regulation of AQ production is known to be complex, and the stimuli that modulate AQ responses are not fully clear. Here, we have used hyperspectral Raman chemical imaging to examine the temporal and spatial profiles of AQs exhibited by P. aeruginosa under several potentially stressful conditions. We found that metabolic stress, effected by carbon limitation, or competition stress, effected by proximity to other species, resulted in accelerated PQS production. This competition effect did not require cell-to-cell interaction, as evidenced by the fact that the addition of supernatants from either Escherichia coli or Staphylococcus aureus led to early appearance of PQS. Lastly, the fact that these modulations were observed for PQS but not for all AQs suggests a high level of complexity in AQ regulation that remains to be discerned.
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27
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Dong L, Pang J, Wang X, Zhang Y, Li G, Hu X, Yang X, Lu CD, Li C, You X. Mechanism of pyocyanin abolishment caused by mvaT mvaU double knockout in Pseudomonas aeruginosa PAO1. Virulence 2020; 11:57-67. [PMID: 31885331 PMCID: PMC6961724 DOI: 10.1080/21505594.2019.1708052] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
Abstract
MvaT and MvaU are global transcriptional regulators belonging to the H-NS family, and pyocyanin is an important virulence factor produced by Pseudomonas aeruginosa. mvaT mvaU double knockout mutant of P. aeruginosa PAO1 demonstrated pyocyanin abolishment in the previous study. Here, we further explored the mechanism. Two main directions were studied: pyocyanin biosynthesis pathway and QS system. The effect on the expression of the pyocyanin biosynthesis genes was evaluated by promoter strength determination and Real-Time PCR assay, and significant changes leading to low pyocyanin production were found. The effect on the QS system was studied by signal molecule quantification using LC-MS/MS and related gene expression measurements using Real-Time PCR. In mvaT mvaU double knockout, the production of 3-oxo-C12-HSL obviously increased, while those of C4-HSL and PQS obviously decreased, and the changes can be recovered by mvaT or mvaU complementation. The expressions of transcriptional activator genes binding with QS system signal molecules were all decreased, resulting in decreased formation of signal-transcriptional activator complexes. And the decreased expression of rhlR and pqsE also led to the lower expression of phzA1 and phzA2. Further exploration found that QS system downregulation may be related to QsrO, a QS system repressor, which was highly upregulated with mvaT mvaU double knockout. Hence, the synthesis of pyocyanin was suffocated and the biofilm formation ability was decreased. These results were also confirmed by transcriptome analysis, which demonstrated similar gene expression changes of the aforementioned genes together with decreased expression of other virulence factor genes regulated by QS system.
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Affiliation(s)
- Limin Dong
- Beijing Key Laboratory of Antimicrobial Agents, Institute of Medicinal Biotechnology, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing, China
| | - Jing Pang
- Beijing Key Laboratory of Antimicrobial Agents, Institute of Medicinal Biotechnology, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing, China
| | - Xiukun Wang
- Beijing Key Laboratory of Antimicrobial Agents, Institute of Medicinal Biotechnology, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing, China
| | - Youwen Zhang
- Beijing Key Laboratory of Antimicrobial Agents, Institute of Medicinal Biotechnology, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing, China
| | - Guoqing Li
- Beijing Key Laboratory of Antimicrobial Agents, Institute of Medicinal Biotechnology, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing, China
| | - Xinxin Hu
- Beijing Key Laboratory of Antimicrobial Agents, Institute of Medicinal Biotechnology, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing, China
| | - Xinyi Yang
- Beijing Key Laboratory of Antimicrobial Agents, Institute of Medicinal Biotechnology, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing, China
| | - Chung-Dar Lu
- Department of Biomedical and Nutritional Sciences, University of Massachusetts at Lowell, Lowell, MA, USA
| | - Congran Li
- Beijing Key Laboratory of Antimicrobial Agents, Institute of Medicinal Biotechnology, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing, China
| | - Xuefu You
- Beijing Key Laboratory of Antimicrobial Agents, Institute of Medicinal Biotechnology, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing, China
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28
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Abe I. Biosynthesis of medicinally important plant metabolites by unusual type III polyketide synthases. J Nat Med 2020; 74:639-646. [PMID: 32500363 PMCID: PMC7456412 DOI: 10.1007/s11418-020-01414-9] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2020] [Accepted: 05/13/2020] [Indexed: 01/05/2023]
Abstract
Recent research progress on the “second generation” type III polyketide synthases is summarized. This class of enzymes catalyzes unusual condensation chemistries of CoA thioesters to generate various core structures of medicinally important plant secondary metabolites, including the R1–C–R2 scaffold of alkyl quinolones, curcuminoids, as well as the 8-azabicyclo[3.2.1]octane ring of tropane alkaloids. The discovery of this fascinating enzyme superfamily provides excellent opportunities for the manipulation of the enzyme reactions to expand the supply of natural and unnatural molecules for future drug development.
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Affiliation(s)
- Ikuro Abe
- Graduate School of Pharmaceutical Sciences, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo, 113-0033, Japan.
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29
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Froes TQ, Baldini RL, Vajda S, Castilho MS. Structure-based Druggability Assessment of Anti-virulence Targets from Pseudomonas aeruginosa. Curr Protein Pept Sci 2020; 20:1189-1203. [PMID: 31038064 DOI: 10.2174/1389203720666190417120758] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2018] [Revised: 02/12/2019] [Accepted: 02/28/2019] [Indexed: 11/22/2022]
Abstract
Antimicrobial Resistance (AMR) represents a serious threat to health and the global economy. However, interest in antibacterial drug development has decreased substantially in recent decades. Meanwhile, anti-virulence drug development has emerged as an attractive alternative to fight AMR. Although several macromolecular targets have been explored for this goal, their druggability is a vital piece of information that has been overlooked. This review explores this subject by showing how structure- based freely available in silico tools, such as PockDrug and FTMap, might be useful for designing novel inhibitors of the pyocyanin biosynthesis pathway and improving the potency/selectivity of compounds that target the Pseudomonas aeruginosa quorum sensing mechanism. The information provided by hotspot analysis, along with binding site features, reveals novel druggable targets (PhzA and PhzS) that remain largely unexplored. However, it also highlights that in silico druggability prediction tools have several limitations that might be overcome in the near future. Meanwhile, anti-virulence drug targets should be assessed by complementary methods, such as the combined use of FTMap/PockDrug, once the consensus druggability classification reduces the risk of wasting resources on undruggable proteins.
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Affiliation(s)
- Thamires Q Froes
- Programa de Pos-Graduacao em Biotecnologia da Universidade Estadual de Feira de Santana, Feira de Santana, BA, Brazil.,aculdade de Farmácia da Universidade Federal da Bahia, Bahia, Salvador, BA, Brazil
| | - Regina L Baldini
- Departamento de Bioquimica, Instituto de Quimica, Universidade de Sao Paulo. Sao Paulo, SP, Brazil
| | - Sandor Vajda
- College of Engineering, Boston University, Boston, MA, United States
| | - Marcelo S Castilho
- Programa de Pos-Graduacao em Biotecnologia da Universidade Estadual de Feira de Santana, Feira de Santana, BA, Brazil.,aculdade de Farmácia da Universidade Federal da Bahia, Bahia, Salvador, BA, Brazil.,College of Engineering, Boston University, Boston, MA, United States
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30
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García-Reyes S, Soberón-Chávez G, Cocotl-Yanez M. The third quorum-sensing system of Pseudomonas aeruginosa: Pseudomonas quinolone signal and the enigmatic PqsE protein. J Med Microbiol 2020; 69:25-34. [PMID: 31794380 DOI: 10.1099/jmm.0.001116] [Citation(s) in RCA: 65] [Impact Index Per Article: 16.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023] Open
Abstract
Pseudomonas aeruginosa is an opportunistic pathogen that produces several virulence factors such as lectin A, pyocyanin, elastase and rhamnolipids. These compounds are controlled transcriptionally by three quorum-sensing circuits, two based on the synthesis and detection of N-acyl-homoserine-lactone termed the Las and Rhl system and a third system named the Pseudomonas quinolone signal (PQS) system, which is responsible for generating 2-alkyl-4(1 h)-quinolones (AQs). The transcriptional regulator called PqsR binds to the promoter of pqsABCDE in the presence of PQS or HHQ creating a positive feedback-loop. PqsE, encoded in the operon for AQ synthesis, is a crucial protein for pyocyanin production, activating the Rhl system by a still not fully understood mechanism. In turn, the regulation of the PQS system is modulated by Las and Rhl systems, which act positively and negatively, respectively. This review focuses on the PQS system, from its discovery to its role in Pseudomonas pathogenesis, such as iron depletion and pyocyanin synthesis that involves the PqsE protein - an intriguing player of this system.
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Affiliation(s)
- Selene García-Reyes
- Departamento de Biología molecular y Biotecnología, Instituto de Investigaciones Biomédicas, Universidad Nacional Autónoma de México, Ciudad Universitaria, Apdo Postal 70228, C.P. 04510, Ciudad de México, Mexico
| | - Gloria Soberón-Chávez
- Departamento de Biología molecular y Biotecnología, Instituto de Investigaciones Biomédicas, Universidad Nacional Autónoma de México, Ciudad Universitaria, Apdo Postal 70228, C.P. 04510, Ciudad de México, Mexico
| | - Miguel Cocotl-Yanez
- Departamento de Microbiología y Parasitología, Facultad de Medicina, Universidad Nacional Autónoma de México. Av. Universidad 3000, Cd. Universitaria, C.P. 04510, Coyoacán, Ciudad de México, Mexico
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31
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Development and bioanalytical method validation of an LC-MS/MS assay for simultaneous quantitation of 2-alkyl-4(1H)-quinolones for application in bacterial cell culture and lung tissue. Anal Bioanal Chem 2020; 412:1521-1534. [PMID: 31993728 PMCID: PMC7223165 DOI: 10.1007/s00216-019-02374-0] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2019] [Revised: 12/13/2019] [Accepted: 12/23/2019] [Indexed: 12/19/2022]
Abstract
Pseudomonas aeruginosa is an opportunistic pathogen that produces numerous exoproducts during infection that help it evade the host immune system and procure nutrients from the host environment. Among these products are a family of secreted 2-alkyl-4(1H)-quinolone metabolites (AQs), which exhibit a range of biological activities. Here, we describe the validation of a liquid chromatography-tandem mass spectrometry (LC-MS/MS)-based method for quantifying multiple AQ congeners in complex biological matrices. The assay was validated for selectivity, sensitivity, linearity, accuracy, precision, carryover, dilution integrity, recovery, matrix effects, and various aspects of stability (freeze-thaw, bench-top, long-term storage, and autosampler/post-preparative). Using authentic standards for 6 distinct AQ congeners, we report accurate quantitation within a linear range between 25 and 1000 nmol/L for all of the validated AQ standards. This method was successfully applied to quantify AQ concentrations in P. aeruginosa cell culture and in the lungs of mice infected with P. aeruginosa. Further, we confirmed the presence of unsaturated forms of several AQ congeners in cell culture. Graphical abstract ![]()
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32
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Zender M, Witzgall F, Kiefer A, Kirsch B, Maurer CK, Kany AM, Xu N, Schmelz S, Börger C, Blankenfeldt W, Empting M. Flexible Fragment Growing Boosts Potency of Quorum-Sensing Inhibitors against Pseudomonas aeruginosa Virulence. ChemMedChem 2019; 15:188-194. [PMID: 31709767 PMCID: PMC7004148 DOI: 10.1002/cmdc.201900621] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2019] [Indexed: 12/24/2022]
Abstract
Hit-to-lead optimization is a critical phase in drug discovery. Herein, we report on the fragment-based discovery and optimization of 2-aminopyridine derivatives as a novel lead-like structure for the treatment of the dangerous opportunistic pathogen Pseudomonas aeruginosa. We pursue an innovative treatment strategy by interfering with the Pseudomonas quinolone signal (PQS) quorum sensing (QS) system leading to an abolishment of bacterial pathogenicity. Our compounds act on the PQS receptor (PqsR), a key transcription factor controlling the expression of various pathogenicity determinants. In this target-driven approach, we made use of biophysical screening via surface plasmon resonance (SPR) followed by isothermal titration calorimetry (ITC)-enabled enthalpic efficiency (EE) evaluation. Hit optimization then involved growth vector identification and exploitation. Astonishingly, the latter was successfully achieved by introducing flexible linkers rather than rigid motifs leading to a boost in activity on the target receptor and anti-virulence potency.
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Affiliation(s)
- Michael Zender
- Drug Design and Optimization (DDOP), Helmholtz-Institute for Pharmaceutical Research Saarland (HIPS)-Helmholtz Centre for Infection Research (HZI), Campus E8.1, 66123, Saarbrücken, Germany
| | - Florian Witzgall
- Structure and Function of Proteins (SFPR), Helmholtz Centre for Infection Research (HZI), Inhoffenstr. 7, 38124, Braunschweig, Germany
| | - Alexander Kiefer
- Drug Design and Optimization (DDOP), Helmholtz-Institute for Pharmaceutical Research Saarland (HIPS)-Helmholtz Centre for Infection Research (HZI), Campus E8.1, 66123, Saarbrücken, Germany
| | - Benjamin Kirsch
- Drug Design and Optimization (DDOP), Helmholtz-Institute for Pharmaceutical Research Saarland (HIPS)-Helmholtz Centre for Infection Research (HZI), Campus E8.1, 66123, Saarbrücken, Germany
| | - Christine K Maurer
- Drug Design and Optimization (DDOP), Helmholtz-Institute for Pharmaceutical Research Saarland (HIPS)-Helmholtz Centre for Infection Research (HZI), Campus E8.1, 66123, Saarbrücken, Germany
| | - Andreas M Kany
- Drug Design and Optimization (DDOP), Helmholtz-Institute for Pharmaceutical Research Saarland (HIPS)-Helmholtz Centre for Infection Research (HZI), Campus E8.1, 66123, Saarbrücken, Germany
| | - Ningna Xu
- Lehrstuhl für Biochemie, Universität Bayreuth, Universitätsstr. 30, 95447, Bayreuth, Germany
| | - Stefan Schmelz
- Structure and Function of Proteins (SFPR), Helmholtz Centre for Infection Research (HZI), Inhoffenstr. 7, 38124, Braunschweig, Germany
| | - Carsten Börger
- PharmBioTec GmbH, Science Park 1, 66123, Saarbrücken, Germany
| | - Wulf Blankenfeldt
- Structure and Function of Proteins (SFPR), Helmholtz Centre for Infection Research (HZI), Inhoffenstr. 7, 38124, Braunschweig, Germany.,Biotechnology and Bioinformatics, Institute for Biochemistry, Technische Universität Braunschweig, Spielmannstr. 7, 38106, Braunschweig, Germany
| | - Martin Empting
- Drug Design and Optimization (DDOP), Helmholtz-Institute for Pharmaceutical Research Saarland (HIPS)-Helmholtz Centre for Infection Research (HZI), Campus E8.1, 66123, Saarbrücken, Germany.,Department of Pharmacy, Saarland University, Campus E8.1, 66123, Saarbrücken, Germany
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PQS Produced by the Pseudomonas aeruginosa Stress Response Repels Swarms Away from Bacteriophage and Antibiotics. J Bacteriol 2019; 201:JB.00383-19. [PMID: 31451543 DOI: 10.1128/jb.00383-19] [Citation(s) in RCA: 40] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2019] [Accepted: 08/21/2019] [Indexed: 11/20/2022] Open
Abstract
We investigate the effect of bacteriophage infection and antibiotic treatment on the coordination of swarming, a collective form of flagellum- and pilus-mediated motility in bacteria. We show that phage infection of the opportunistic bacterial pathogen Pseudomonas aeruginosa abolishes swarming motility in the infected subpopulation and induces the release of the Pseudomonas quinolone signaling molecule PQS, which repulses uninfected subpopulations from approaching the infected area. These mechanisms have the overall effect of limiting the infection to a subpopulation, which promotes the survival of the overall population. Antibiotic treatment of P. aeruginosa elicits the same response, abolishing swarming motility and repulsing approaching swarms away from the antibiotic-treated area through a PQS-dependent mechanism. Swarms are entirely repelled from the zone of antibiotic-treated P. aeruginosa, consistent with a form of antibiotic evasion, and are not repelled by antibiotics alone. PQS has multiple functions, including serving as a quorum-sensing molecule, activating an oxidative stress response, and regulating the release of virulence and host-modifying factors. We show that PQS serves additionally as a stress warning signal that causes the greater population to physically avoid cell stress. The stress response at the collective level observed here in P. aeruginosa is consistent with a mechanism that promotes the survival of bacterial populations.IMPORTANCE We uncover a phage- and antibiotic-induced stress response in the clinically important opportunistic pathogen Pseudomonas aeruginosa Phage-infected P. aeruginosa subpopulations are isolated from uninfected subpopulations by the production of a stress-induced signal. Activation of the stress response by antibiotics causes P. aeruginosa to physically be repelled from the area containing antibiotics altogether, consistent with a mechanism of antibiotic evasion. The stress response observed here could increase P. aeruginosa resilience against antibiotic treatment and phage therapy in health care settings, as well as provide a simple evolutionary strategy to avoid areas containing stress.
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34
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Synthesis of New Fused Heterocyclic 2-Quinolones and 3-Alkanonyl-4-Hydroxy-2-Quinolones. Molecules 2019; 24:molecules24203782. [PMID: 31640196 PMCID: PMC6832483 DOI: 10.3390/molecules24203782] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2019] [Revised: 10/07/2019] [Accepted: 10/17/2019] [Indexed: 11/17/2022] Open
Abstract
Herein, we report the synthesis of 5,12-dihydropyrazino[2,3-c:5,6-c′]difuro[2,3-c:4,5-c′]-diquinoline-6,14(5H,12H)diones, 2-(4-hydroxy-2-oxo-1,2-dihydroquinolin-3-yl)-1,4-diphenyl- butane-1,4-diones and 4-(benzo-[d]oxazol-2-yl)-3-hydroxy-1H-[4,5]oxazolo[3,2-a]pyridine-1-one. The new candidates were synthesized and identified by different spectroscopic techniques, and X-ray crystallography.
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35
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Mellini M, Di Muzio E, D’Angelo F, Baldelli V, Ferrillo S, Visca P, Leoni L, Polticelli F, Rampioni G. In silico Selection and Experimental Validation of FDA-Approved Drugs as Anti-quorum Sensing Agents. Front Microbiol 2019; 10:2355. [PMID: 31649658 PMCID: PMC6796623 DOI: 10.3389/fmicb.2019.02355] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2019] [Accepted: 09/27/2019] [Indexed: 12/13/2022] Open
Abstract
The emergence of antibiotic resistant bacterial pathogens is increasing at an unprecedented pace, calling for the development of new therapeutic options. Small molecules interfering with virulence processes rather than growth hold promise as an alternative to conventional antibiotics. Anti-virulence agents are expected to decrease bacterial virulence and to pose reduced selective pressure for the emergence of resistance. In the opportunistic pathogen Pseudomonas aeruginosa the expression of key virulence traits is controlled by quorum sensing (QS), an intercellular communication process that coordinates gene expression at the population level. Hence, QS inhibitors represent promising anti-virulence agents against P. aeruginosa. Virtual screenings allow fast and cost-effective selection of target ligands among vast libraries of molecules, thus accelerating the time and limiting the cost of conventional drug-discovery processes, while the drug-repurposing approach is based on the identification of off-target activity of FDA-approved drugs, likely endowed with low cytotoxicity and favorable pharmacological properties. This study aims at combining the advantages of virtual screening and drug-repurposing approaches to identify new QS inhibitors targeting the pqs QS system of P. aeruginosa. An in silico library of 1,467 FDA-approved drugs has been screened by molecular docking, and 5 hits showing the highest predicted binding affinity for the pqs QS receptor PqsR (also known as MvfR) have been selected. In vitro experiments have been performed by engineering ad hoc biosensor strains, which were used to verify the ability of hit compounds to decrease PqsR activity in P. aeruginosa. Phenotypic analyses confirmed the impact of the most promising hit, the antipsychotic drug pimozide, on the expression of P. aeruginosa PqsR-controlled virulence traits. Overall, this study highlights the potential of virtual screening campaigns of FDA-approved drugs to rapidly select new inhibitors of important bacterial functions.
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Affiliation(s)
- Marta Mellini
- Department of Science, University Roma Tre, Rome, Italy
| | | | | | | | | | - Paolo Visca
- Department of Science, University Roma Tre, Rome, Italy
| | - Livia Leoni
- Department of Science, University Roma Tre, Rome, Italy
| | - Fabio Polticelli
- Department of Science, University Roma Tre, Rome, Italy
- National Institute of Nuclear Physics, Roma Tre Section, Rome, Italy
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36
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Reen FJ, McGlacken GP, O'Gara F. The expanding horizon of alkyl quinolone signalling and communication in polycellular interactomes. FEMS Microbiol Lett 2019; 365:4953739. [PMID: 29718276 DOI: 10.1093/femsle/fny076] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2017] [Accepted: 03/25/2018] [Indexed: 02/07/2023] Open
Abstract
Population dynamics within natural ecosystems is underpinned by microbial diversity and the heterogeneity of host-microbe and microbe-microbe interactions. Small molecule signals that intersperse between species have been shown to govern many virulence-related processes in established and emerging pathogens. Understanding the capacity of microbes to decode diverse languages and adapt to the presence of 'non-self' cells will provide an important new direction to the understanding of the 'polycellular' interactome. Alkyl quinolones (AQs) have been described in the ESKAPE pathogen Pseudomonas aeruginosa, the primary agent associated with mortality in patients with cystic fibrosis and the third most prevalent nosocomial pathogen worldwide. The role of these molecules in governing the physiology and virulence of P. aeruginosa and other pathogens has received considerable attention, while a role in interspecies and interkingdom communication has recently emerged. Herein we discuss recent advances in our understanding of AQ signalling and communication in the context of microbe-microbe and microbe-host interactions. The integrated knowledge from these systems-based investigations will facilitate the development of new therapeutics based on the AQ framework that serves to disarm the pathogenesis of P. aeruginosa and competing pathogens.
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Affiliation(s)
- F Jerry Reen
- School of Microbiology, University College Cork, Cork, Ireland
| | - Gerard P McGlacken
- School of Chemistry and Analytical & Biological Chemistry Research Facility (ABCRF), University College Cork, Ireland
| | - Fergal O'Gara
- BIOMERIT Research Centre, School of Microbiology, University College Cork, Cork, Ireland
- Human Microbiome Programme, School of Pharmacy and Biomedical Sciences, Curtin Health Innovation Research Institute, Curtin University, Perth, WA 6102, USA
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37
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Morita H, Wong CP, Abe I. How structural subtleties lead to molecular diversity for the type III polyketide synthases. J Biol Chem 2019; 294:15121-15136. [PMID: 31471316 DOI: 10.1074/jbc.rev119.006129] [Citation(s) in RCA: 45] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
Type III polyketide synthases (PKSs) produce an incredibly diverse group of plant specialized metabolites with medical importance despite their structural simplicity compared with the modular type I and II PKS systems. The type III PKSs use homodimeric proteins to construct the molecular scaffolds of plant polyketides by iterative condensations of starter and extender CoA thioesters. Ever since the structure of chalcone synthase (CHS) was disclosed in 1999, crystallographic and mutational studies of the type III PKSs have explored the intimate structural features of these enzyme reactions, revealing that seemingly minor alterations in the active site can drastically change the catalytic functions and product profiles. New structures described in this review further build on this knowledge, elucidating the detailed catalytic mechanism of enzymes that make curcuminoids, use extender substrates without the canonical CoA activator, and use noncanonical starter substrates, among others. These insights have been critical in identifying structural features that can serve as a platform for enzyme engineering via structure-guided and precursor-directed engineered biosynthesis of plant polyketides. In addition, we describe the unique properties of the recently discovered "second-generation" type III PKSs that catalyzes the one-pot formation of complex molecular scaffolds from three distinct CoA thioesters or from "CoA-free" substrates, which are also providing exciting new opportunities for synthetic biology approaches. Finally, we consider post-type III PKS tailoring enzymes, which can also serve as useful tools for combinatorial biosynthesis of further unnatural novel molecules. Recent progress in the field has led to an exciting time of understanding and manipulating these fascinating enzymes.
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Affiliation(s)
- Hiroyuki Morita
- Institute of Natural Medicine, University of Toyama, 2630-Sugitani, Toyama 930-0194, Japan
| | - Chin Piow Wong
- Institute of Natural Medicine, University of Toyama, 2630-Sugitani, Toyama 930-0194, Japan
| | - Ikuro Abe
- Graduate School of Pharmaceutical Sciences, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan .,Collaborative Research Institute for Innovative Microbiology, The University of Tokyo, Yayoi 1-1-1, Bunkyo-ku, Tokyo 113-8657, Japan
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38
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Shen C, Wang A, Xu J, An Z, Loh KY, Zhang P, Liu X. Recent Advances in the Catalytic Synthesis of 4-Quinolones. Chem 2019. [DOI: 10.1016/j.chempr.2019.01.006] [Citation(s) in RCA: 34] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
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39
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Fleitas Martínez O, Cardoso MH, Ribeiro SM, Franco OL. Recent Advances in Anti-virulence Therapeutic Strategies With a Focus on Dismantling Bacterial Membrane Microdomains, Toxin Neutralization, Quorum-Sensing Interference and Biofilm Inhibition. Front Cell Infect Microbiol 2019; 9:74. [PMID: 31001485 PMCID: PMC6454102 DOI: 10.3389/fcimb.2019.00074] [Citation(s) in RCA: 152] [Impact Index Per Article: 30.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2018] [Accepted: 03/05/2019] [Indexed: 12/11/2022] Open
Abstract
Antimicrobial resistance constitutes one of the major challenges facing humanity in the Twenty-First century. The spread of resistant pathogens has been such that the possibility of returning to a pre-antibiotic era is real. In this scenario, innovative therapeutic strategies must be employed to restrict resistance. Among the innovative proposed strategies, anti-virulence therapy has been envisioned as a promising alternative for effective control of the emergence and spread of resistant pathogens. This review presents some of the anti-virulence strategies that are currently being developed, it will cover strategies focused on quench pathogen quorum sensing (QS) systems, disassemble of bacterial functional membrane microdomains (FMMs), disruption of biofilm formation and bacterial toxin neutralization.
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Affiliation(s)
- Osmel Fleitas Martínez
- Programa de Pós-Graduação em Patologia Molecular, Faculdade de Medicina, Universidade de Brasília, Brasília, Brazil.,Programa de Pós-Graduação em Ciências Genômicas e Biotecnologia, Centro de Análises Proteômicas e Bioquímicas, Universidade Católica de Brasília, Brasília, Brazil
| | - Marlon Henrique Cardoso
- Programa de Pós-Graduação em Patologia Molecular, Faculdade de Medicina, Universidade de Brasília, Brasília, Brazil.,Programa de Pós-Graduação em Ciências Genômicas e Biotecnologia, Centro de Análises Proteômicas e Bioquímicas, Universidade Católica de Brasília, Brasília, Brazil.,S-inova Biotech, Programa de Pós-Graduação em Biotecnologia, Universidade Católica Dom Bosco, Campo Grande, Brazil
| | - Suzana Meira Ribeiro
- Programa de Pós-Graduação em Ciências da Saúde, Universidade Federal da Grande Dourados, Dourados, Brazil
| | - Octavio Luiz Franco
- Programa de Pós-Graduação em Patologia Molecular, Faculdade de Medicina, Universidade de Brasília, Brasília, Brazil.,Programa de Pós-Graduação em Ciências Genômicas e Biotecnologia, Centro de Análises Proteômicas e Bioquímicas, Universidade Católica de Brasília, Brasília, Brazil.,S-inova Biotech, Programa de Pós-Graduação em Biotecnologia, Universidade Católica Dom Bosco, Campo Grande, Brazil
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40
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Coulon PML, Groleau MC, Déziel E. Potential of the Burkholderia cepacia Complex to Produce 4-Hydroxy-3-Methyl-2-Alkyquinolines. Front Cell Infect Microbiol 2019; 9:33. [PMID: 30873388 PMCID: PMC6403149 DOI: 10.3389/fcimb.2019.00033] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2018] [Accepted: 02/01/2019] [Indexed: 12/22/2022] Open
Abstract
A few Burkholderia species, especially Burkholderia pseudomallei, Burkholderia thailandensis, Burkholderia ambifaria, and Burkholderia cepacia, are known to produce and release various 4-hydroxy-3-methyl-2-alkylquinolines (HMAQs), a family of molecules analogous to the 4-hydroxy-2-alkylquinolines [aka 2-n-alkyl-4(1H)-quinolones] of Pseudomonas aeruginosa, which include the Pseudomonas quinolone signal (PQS). However, while these exoproducts play several roles in P. aeruginosa virulence and survival, the available literature is very limited on their distribution and function in Burkholderia. In this perspective article, we studied the distribution of the hmqABCDEFG operon, which encodes the enzymes involved in the biosynthesis of HMAQs, in the Burkholderia cepacia complex (Bcc) group. Based on the available sequence data, about one third of Bcc species carry a homolog of the hmqABCDEFG, and not all sequenced strains in a given species possess this operon. Looking at the synteny of genes surrounding the hmqABCDEFG operon, we found that for some species, the operon seems to have been deleted or replaced by other genes. Finally, we review the literature on the possible function of HMAQs. Understanding the Hmq system may provide clues concerning their functions in Bcc.
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Affiliation(s)
- Pauline M L Coulon
- Institut Armand Frappier, Institut National de la Recherche Scientifique, Laval, QC, Canada
| | | | - Eric Déziel
- Institut Armand Frappier, Institut National de la Recherche Scientifique, Laval, QC, Canada
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41
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Zhang D, Zhang F, Liu W. A KAS-III Heterodimer in Lipstatin Biosynthesis Nondecarboxylatively Condenses C 8 and C 14 Fatty Acyl-CoA Substrates by a Variable Mechanism during the Establishment of a C 22 Aliphatic Skeleton. J Am Chem Soc 2019; 141:3993-4001. [PMID: 30763089 DOI: 10.1021/jacs.8b12843] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
β-Ketoacyl-acyl carrier protein synthase-III (KAS-III) and its homologues are thiolase-fold proteins that typically behave as homodimers functioning in diverse thioester-based reactions for C-C, C-O, or C-N bond formation. Here, we report an exception observed in the biosynthesis of lipstatin. During the establishment of the C22 aliphatic skeleton of this β-lactone lipase inhibitor, LstA and LstB, which both are KAS-III homologues but phylogenetically distinct from each other, function together by forming an unusual heterodimer to catalyze a nondecarboxylating Claisen condensation of C8 and C14 fatty acyl-CoA substrates. The resulting C22 α-alkyl β-ketoacid, which is unstable and tends to be spontaneously decarboxylated to a shunt C21 hydrocarbon product, is transformed by the stereoselective β-ketoreductase LstD into a relatively stable C22 α-alkyl β-hydroxyacid for further transformation. LstAB activity tolerates changes in the stereochemistry, saturation degree, and thioester form of both long-chain fatty acyl-CoA substrates. This flexibility, along with the characterization of catalytic residues, benefits our investigations into the individual roles of the two KAS-III homologues in the heterodimer-catalyzed reactions. The large subunit LstA contains a characteristic Cys-His-Asn triad and likely reacts with C8 acyl-CoA to form an acyl-Cys enzyme intermediate. In contrast, the small subunit LstB lacks this triad but possesses a catalytic Glu residue, which can act on the C8 acyl-Cys enzyme intermediate in a substrate-dependent manner, either as a base for Cα deprotonation or as a nucleophile for a Michael-type addition-initiated cascade reaction, to produce an enolate anion for head-to-head assembly with C14 acyl-CoA through a unidirectional nucleophilic substitution. Uncovering LstAB catalysis draws attention to thiolase-fold proteins that are noncanonical in both active form and catalytic reaction/mechanism. LstAB homologues are widespread in bacteria and remain to be functionally assigned, generating great interest in their corresponding products and associated biological functions.
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Affiliation(s)
- Daozhong Zhang
- State Key Laboratory of Bioorganic and Natural Products Chemistry, Center for Excellence in Molecular Synthesis, Shanghai Institute of Organic Chemistry , University of Chinese Academy of Sciences , 345 Lingling Road , Shanghai 200032 , China
| | - Fang Zhang
- Innovation Research Institute of Traditional Chinese Medicine , Shanghai University of Traditional Chinese Medicine , 1200 Cailun Road , Shanghai 201203 , China
| | - Wen Liu
- State Key Laboratory of Bioorganic and Natural Products Chemistry, Center for Excellence in Molecular Synthesis, Shanghai Institute of Organic Chemistry , University of Chinese Academy of Sciences , 345 Lingling Road , Shanghai 200032 , China.,Huzhou Center of Bio-Synthetic Innovation , 1366 Hongfeng Road , Huzhou 313000 , China
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Fleitas Martínez O, Rigueiras PO, Pires ÁDS, Porto WF, Silva ON, de la Fuente-Nunez C, Franco OL. Interference With Quorum-Sensing Signal Biosynthesis as a Promising Therapeutic Strategy Against Multidrug-Resistant Pathogens. Front Cell Infect Microbiol 2019; 8:444. [PMID: 30805311 PMCID: PMC6371041 DOI: 10.3389/fcimb.2018.00444] [Citation(s) in RCA: 37] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2018] [Accepted: 12/12/2018] [Indexed: 12/11/2022] Open
Abstract
Faced with the global health threat of increasing resistance to antibiotics, researchers are exploring interventions that target bacterial virulence factors. Quorum sensing is a particularly attractive target because several bacterial virulence factors are controlled by this mechanism. Furthermore, attacking the quorum-sensing signaling network is less likely to select for resistant strains than using conventional antibiotics. Strategies that focus on the inhibition of quorum-sensing signal production are especially attractive because the enzymes involved are expressed in bacterial cells but are not present in their mammalian counterparts. We review here various approaches that are being taken to interfere with quorum-sensing signal production via the inhibition of autoinducer-2 synthesis, PQS synthesis, peptide autoinducer synthesis, and N-acyl-homoserine lactone synthesis. We expect these approaches will lead to the discovery of new quorum-sensing inhibitors that can help to stem the tide of antibiotic resistance.
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Affiliation(s)
- Osmel Fleitas Martínez
- Programa de Pós-Graduação em Patologia Molecular, Universidade de Brasília, Brasília, Brazil.,Centro de Análises Proteômicas e Bioquímicas, Universidade Católica de Brasília, Brasília, Brazil
| | - Pietra Orlandi Rigueiras
- Centro de Análises Proteômicas e Bioquímicas, Universidade Católica de Brasília, Brasília, Brazil
| | - Állan da Silva Pires
- Centro de Análises Proteômicas e Bioquímicas, Universidade Católica de Brasília, Brasília, Brazil
| | - William Farias Porto
- Centro de Análises Proteômicas e Bioquímicas, Universidade Católica de Brasília, Brasília, Brazil.,S-Inova Biotech, Programa de Pós-Graduação em Biotecnologia, Universidade Católica Dom Bosco, Campo Grande, Brazil.,Porto Reports, Brasília, Brazil
| | - Osmar Nascimento Silva
- S-Inova Biotech, Programa de Pós-Graduação em Biotecnologia, Universidade Católica Dom Bosco, Campo Grande, Brazil
| | - Cesar de la Fuente-Nunez
- Synthetic Biology Group, MIT Synthetic Biology Center, Massachusetts Institute of Technology, Cambridge, MA, United States.,Research Laboratory of Electronics, Massachusetts Institute of Technology, Cambridge, MA, United States.,Department of Biological Engineering, Department of Electrical Engineering and Computer Science, Massachusetts Institute of Technology, Cambridge, MA, United States.,Broad Institute of MIT and Harvard, Cambridge, MA, United States.,The Center for Microbiome Informatics and Therapeutics, Cambridge, MA, United States
| | - Octavio Luiz Franco
- Programa de Pós-Graduação em Patologia Molecular, Universidade de Brasília, Brasília, Brazil.,Centro de Análises Proteômicas e Bioquímicas, Universidade Católica de Brasília, Brasília, Brazil.,S-Inova Biotech, Programa de Pós-Graduação em Biotecnologia, Universidade Católica Dom Bosco, Campo Grande, Brazil
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43
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Alcalde-Rico M, Olivares-Pacheco J, Alvarez-Ortega C, Cámara M, Martínez JL. Role of the Multidrug Resistance Efflux Pump MexCD-OprJ in the Pseudomonas aeruginosa Quorum Sensing Response. Front Microbiol 2018; 9:2752. [PMID: 30532741 PMCID: PMC6266676 DOI: 10.3389/fmicb.2018.02752] [Citation(s) in RCA: 46] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2018] [Accepted: 10/26/2018] [Indexed: 11/15/2022] Open
Abstract
Multidrug efflux pumps constitute a category of antibiotic resistance determinants that are a part of the core bacterial genomes. Given their conservation, it is conceivable that they present functions beyond the extrusion of antibiotics currently used for therapy. Pseudomonas aeruginosa stands as a relevant respiratory pathogen, with a high prevalence at hospitals and in cystic fibrosis patients. Part of its success relies on its low susceptibility to antibiotics and on the production of virulence factors, whose expression is regulated in several cases by quorum sensing (QS). We found that overexpression of the MexCD-OprJ multidrug efflux pump shuts down the P. aeruginosa QS response. Our results support that MexCD-OprJ extrudes kynurenine, a precursor of the alkyl-quinolone signal (AQS) molecules. Anthranilate and octanoate, also AQS precursors, do not seem to be extruded by MexCD-OprJ. Kynurenine extrusion is not sufficient to reduce the QS response in a mutant overexpressing this efflux pump. Impaired QS response is mainly due to the extrusion of 4-hydroxy-2-heptylquinoline (HHQ), the precursor of the Pseudomonas Quinolone Signal (PQS), leading to low PQS intracellular levels and reduced production of QS signal molecules. As the consequence, the expression of QS-regulated genes is impaired and the production of QS-regulated virulence factors strongly decreases in a MexCD-OprN P. aeruginosa overexpressing mutant. Previous work showed that MexEF-OprJ, another P. aeruginosa efflux pump, is also able of extruding kynurenine and HHQ. However, opposite to our findings, the QS defect in a MexEF-OprN overproducer is due to kynurenine extrusion. These results indicate that, although efflux pumps can share some substrates, the affinity for each of them can be different. Although the QS response is triggered by population density, information on additional elements able of modulating such response is still scarce. This is particularly important in the case of P. aeruginosa lung chronic infections, a situation in which QS-defective mutants are accumulated. If MexCD-OprJ overexpression alleviates the cost associated to triggering the QS response when un-needed, it could be possible that MexCD-OprJ antibiotic resistant overproducer strains might be selected even in the absence of antibiotic selective pressure, acting as antibiotic resistant cheaters in heterogeneous P. aeruginosa populations.
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Affiliation(s)
- Manuel Alcalde-Rico
- Centro Nacional de Biotecnología, Consejo Superior de Investigaciones Científicas, Madrid, Spain
| | - Jorge Olivares-Pacheco
- Centro Nacional de Biotecnología, Consejo Superior de Investigaciones Científicas, Madrid, Spain
| | - Carolina Alvarez-Ortega
- Centro Nacional de Biotecnología, Consejo Superior de Investigaciones Científicas, Madrid, Spain
| | - Miguel Cámara
- Centre for Biomolecular Sciences, School of Life Sciences, University of Nottingham, Nottingham, United Kingdom
| | - José Luis Martínez
- Centro Nacional de Biotecnología, Consejo Superior de Investigaciones Científicas, Madrid, Spain
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44
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D'Angelo F, Baldelli V, Halliday N, Pantalone P, Polticelli F, Fiscarelli E, Williams P, Visca P, Leoni L, Rampioni G. Identification of FDA-Approved Drugs as Antivirulence Agents Targeting the pqs Quorum-Sensing System of Pseudomonas aeruginosa. Antimicrob Agents Chemother 2018; 62:e01296-18. [PMID: 30201815 PMCID: PMC6201120 DOI: 10.1128/aac.01296-18] [Citation(s) in RCA: 66] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2018] [Accepted: 09/01/2018] [Indexed: 12/11/2022] Open
Abstract
The long-term use of antibiotics has led to the emergence of multidrug-resistant bacteria. A promising strategy to combat bacterial infections aims at hampering their adaptability to the host environment without affecting growth. In this context, the intercellular communication system quorum sensing (QS), which controls virulence factor production and biofilm formation in diverse human pathogens, is considered an ideal target. Here, we describe the identification of new inhibitors of the pqs QS system of the human pathogen Pseudomonas aeruginosa by screening a library of 1,600 U.S. Food and Drug Administration-approved drugs. Phenotypic characterization of ad hoc engineered strains and in silico molecular docking demonstrated that the antifungal drugs clotrimazole and miconazole, as well as an antibacterial compound active against Gram-positive pathogens, clofoctol, inhibit the pqs system, probably by targeting the transcriptional regulator PqsR. The most active inhibitor, clofoctol, specifically inhibited the expression of pqs-controlled virulence traits in P. aeruginosa, such as pyocyanin production, swarming motility, biofilm formation, and expression of genes involved in siderophore production. Moreover, clofoctol protected Galleria mellonella larvae from P. aeruginosa infection and inhibited the pqs QS system in P. aeruginosa isolates from cystic fibrosis patients. Notably, clofoctol is already approved for clinical treatment of pulmonary infections caused by Gram-positive bacterial pathogens; hence, this drug has considerable clinical potential as an antivirulence agent for the treatment of P. aeruginosa lung infections.
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Affiliation(s)
| | | | - Nigel Halliday
- Centre for Biomolecular Sciences and School of Life Sciences, University of Nottingham, Nottingham, United Kingdom
| | - Paolo Pantalone
- Centre for Biomolecular Sciences and School of Life Sciences, University of Nottingham, Nottingham, United Kingdom
| | - Fabio Polticelli
- Department of Science, University Roma Tre, Rome, Italy
- National Institute of Nuclear Physics, Roma Tre Section, Rome, Italy
| | - Ersilia Fiscarelli
- Laboratory of Cystic Fibrosis Microbiology, Bambino Gesú Hospital, Rome, Italy
| | - Paul Williams
- Centre for Biomolecular Sciences and School of Life Sciences, University of Nottingham, Nottingham, United Kingdom
| | - Paolo Visca
- Department of Science, University Roma Tre, Rome, Italy
| | - Livia Leoni
- Department of Science, University Roma Tre, Rome, Italy
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45
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Prothiwa M, Englmaier F, Böttcher T. Competitive Live-Cell Profiling Strategy for Discovering Inhibitors of the Quinolone Biosynthesis of Pseudomonas aeruginosa. J Am Chem Soc 2018; 140:14019-14023. [DOI: 10.1021/jacs.8b07629] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Michaela Prothiwa
- Department of Chemistry, Konstanz Research School Chemical Biology, Zukunftskolleg, University of Konstanz, 78457 Konstanz, Germany
| | - Felix Englmaier
- Department of Chemistry, Konstanz Research School Chemical Biology, Zukunftskolleg, University of Konstanz, 78457 Konstanz, Germany
| | - Thomas Böttcher
- Department of Chemistry, Konstanz Research School Chemical Biology, Zukunftskolleg, University of Konstanz, 78457 Konstanz, Germany
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46
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Schütz C, Empting M. Targeting the Pseudomonas quinolone signal quorum sensing system for the discovery of novel anti-infective pathoblockers. Beilstein J Org Chem 2018; 14:2627-2645. [PMID: 30410625 PMCID: PMC6204780 DOI: 10.3762/bjoc.14.241] [Citation(s) in RCA: 38] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2018] [Accepted: 09/28/2018] [Indexed: 12/12/2022] Open
Abstract
The Gram-negative opportunistic pathogen Pseudomonas aeruginosa causes severe nosocomial infections. It uses quorum sensing (QS) to regulate and coordinate population-wide group behaviours in the infection process like concerted secretion of virulence factors. One very important signalling network is the Pseudomonas quinolone signal (PQS) QS. With the aim to devise novel and innovative anti-infectives, inhibitors have been designed to address the various potential drug targets present within pqs QS. These range from enzymes within the biosynthesis cascade of the signal molecules PqsABCDE to the receptor of these autoinducers PqsR (MvfR). This review shortly introduces P. aeruginosa and its pathogenicity traits regulated by the pqs system and highlights the published drug discovery efforts providing insights into the compound binding modes if available. Furthermore, suitability of the individual targets for pathoblocker design is discussed.
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Affiliation(s)
- Christian Schütz
- Helmholtz-Institute for Pharmaceutical Research Saarland (HIPS) - Helmholtz Centre for Infection Research (HZI), Department of Drug Design and Optimization (DDOP), Campus E8.1, 66123 Saarbrücken, Germany.,Department of Pharmacy, Saarland University, Campus E8.1, 66123 Saarbrücken, Germany
| | - Martin Empting
- Helmholtz-Institute for Pharmaceutical Research Saarland (HIPS) - Helmholtz Centre for Infection Research (HZI), Department of Drug Design and Optimization (DDOP), Campus E8.1, 66123 Saarbrücken, Germany.,Department of Pharmacy, Saarland University, Campus E8.1, 66123 Saarbrücken, Germany.,German Centre for Infection Research (DZIF), Partner Site Hannover-Braunschweig, Saarbrücken, Germany
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47
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Chen W, Wang B, Gruber JD, Zhang YM, Davies C. Acyl Carrier Protein 3 Is Involved in Oxidative Stress Response in Pseudomonas aeruginosa. Front Microbiol 2018; 9:2244. [PMID: 30294316 PMCID: PMC6158461 DOI: 10.3389/fmicb.2018.02244] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2018] [Accepted: 09/03/2018] [Indexed: 12/01/2022] Open
Abstract
The human opportunistic pathogen Pseudomonas aeruginosa expresses three acyl carrier proteins (ACPs): AcpP, Acp1, and Acp3. The function of AcpP in membrane fatty acid synthesis (FAS) was confirmed recently, but the physiological roles of Acp1 and Acp3 remain unclear. To address this, we investigated the physiological role of Acp3 in P. aeruginosa. We found that expression of Acp3 dramatically increases in the log phase of cell growth and that its transcription is under the control of the QS regulators LasR and RhlR. Deletion of acp3 from P. aeruginosa strain PAO1 results in thicker biofilm formation, increased resistance of the strain to hydrogen peroxide, and higher persistence in a mouse infection model. Tandem affinity purification (TAP) experiments revealed several novel protein-binding partners of Acp3, including KatA, the major catalase in P. aeruginosa. Acp3 was found to repress the catalase activity of KatA and, consistent with inhibition by Acp3, less reactive oxygen species are present in the acp3 deletion strain. Overall, our study reveals that Acp3 has a distinct function from that of the canonical AcpP and may be involved in the oxidative stress response.
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Affiliation(s)
- Wei Chen
- Clinical Research Center, The Second Affiliated Hospital of the Southeast University, Nanjing, China.,Department of Biochemistry and Molecular Biology, Medical University of South Carolina, Charleston, SC, United States
| | - Bo Wang
- Institute of Medicinal Biotechnology, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China
| | - Jordon D Gruber
- Department of Biochemistry and Molecular Biology, Medical University of South Carolina, Charleston, SC, United States
| | - Yong-Mei Zhang
- Department of Biochemistry and Molecular Biology, Medical University of South Carolina, Charleston, SC, United States
| | - Christopher Davies
- Department of Biochemistry and Molecular Biology, Medical University of South Carolina, Charleston, SC, United States
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48
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Soukarieh F, Williams P, Stocks MJ, Cámara M. Pseudomonas aeruginosa Quorum Sensing Systems as Drug Discovery Targets: Current Position and Future Perspectives. J Med Chem 2018; 61:10385-10402. [PMID: 29999316 DOI: 10.1021/acs.jmedchem.8b00540] [Citation(s) in RCA: 90] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Antimicrobial resistance (AMR) is a serious threat to public health globally, manifested by the frequent emergence of multidrug resistant pathogens that render current chemotherapy inadequate. Health organizations worldwide have recognized the severity of this crisis and implemented action plans to contain its adverse consequences and prolong the utility of conventional antibiotics. Hence, there is a pressing need for new classes of antibacterial agents with novel modes of action. Quorum sensing (QS), a communication system employed by bacterial populations to coordinate virulence gene expression, is a potential target that has been intensively investigated over the past decade. This Perspective will focus on recent advances in targeting the three main quorum sensing systems ( las, rhl, and pqs) of a major opportunistic human pathogen, Pseudomonas aeruginosa, and will specifically evaluate the medicinal chemistry strategies devised to develop QS inhibitors from a drug discovery perspective.
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Affiliation(s)
- Fadi Soukarieh
- School of Life Sciences, Centre for Biomolecular Sciences , University of Nottingham , Nottingham , NG7 2RD , U.K
| | - Paul Williams
- School of Life Sciences, Centre for Biomolecular Sciences , University of Nottingham , Nottingham , NG7 2RD , U.K
| | - Michael J Stocks
- School of Pharmacy, Centre for Biomolecular Sciences , University of Nottingham , Nottingham , NG7 2RD , U.K
| | - Miguel Cámara
- School of Life Sciences, Centre for Biomolecular Sciences , University of Nottingham , Nottingham , NG7 2RD , U.K
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49
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Higgins S, Heeb S, Rampioni G, Fletcher MP, Williams P, Cámara M. Differential Regulation of the Phenazine Biosynthetic Operons by Quorum Sensing in Pseudomonas aeruginosa PAO1-N. Front Cell Infect Microbiol 2018; 8:252. [PMID: 30083519 PMCID: PMC6064868 DOI: 10.3389/fcimb.2018.00252] [Citation(s) in RCA: 64] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2018] [Accepted: 07/03/2018] [Indexed: 01/26/2023] Open
Abstract
The Pseudomonas aeruginosa quorum sensing (QS) network plays a key role in the adaptation to environmental changes and the control of virulence factor production in this opportunistic human pathogen. Three interlinked QS systems, namely las, rhl, and pqs, are central to the production of pyocyanin, a phenazine virulence factor which is typically used as phenotypic marker for analysing QS. Pyocyanin production in P. aeruginosa is a complex process involving two almost identical operons termed phzA1B1C1D1E1F1G1 (phz1) and phzA2B2C2D2E2F2G2 (phz2), which drive the production of phenazine-1-carboxylic acid (PCA) which is further converted to pyocyanin by two modifying enzymes PhzM and PhzS. Due to the high sequence conservation between the phz1 and phz2 operons (nucleotide identity > 98%), analysis of their individual expression by RNA hybridization, qRT-PCR or transcriptomics is challenging. To overcome this difficulty, we utilized luminescence based promoter fusions of each phenazine operon to measure in planktonic cultures their transcriptional activity in P. aeruginosa PAO1-N genetic backgrounds impaired in different components of the las, rhl, and pqs QS systems, in the presence or absence of different QS signal molecules. Using this approach, we found that all three QS systems play a role in differentially regulating the phz1 and phz2 phenazine operons, thus uncovering a higher level of complexity to the QS regulation of PCA biosynthesis in P. aeruginosa than previously appreciated. Importance The way the P. aeruginosa QS regulatory networks are intertwined creates a challenge when analysing the mechanisms governing specific QS-regulated traits. Multiple QS regulators and signals have been associated with the production of phenazine virulence factors. In this work we designed experiments where we dissected the contribution of specific QS switches using individual mutations and complementation strategies to gain further understanding of the specific roles of these QS elements in controlling expression of the two P. aeruginosa phenazine operons. Using this approach we have teased out which QS regulators have either indirect or direct effects on the regulation of the two phenazine biosynthetic operons. The data obtained highlight the sophistication of the QS cascade in P. aeruginosa and the challenges in analysing the control of phenazine secondary metabolites.
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Affiliation(s)
- Steven Higgins
- Centre for Biomolecular Science, School of Life Science, University of Nottingham, Nottingham, United Kingdom
- Department of Plant and Microbial Biology, University of Zürich, Zurich, Switzerland
| | - Stephan Heeb
- Centre for Biomolecular Science, School of Life Science, University of Nottingham, Nottingham, United Kingdom
| | - Giordano Rampioni
- Centre for Biomolecular Science, School of Life Science, University of Nottingham, Nottingham, United Kingdom
- Department of Science, University Roma Tre, Rome, Italy
| | - Mathew P. Fletcher
- Centre for Biomolecular Science, School of Life Science, University of Nottingham, Nottingham, United Kingdom
| | - Paul Williams
- Centre for Biomolecular Science, School of Life Science, University of Nottingham, Nottingham, United Kingdom
| | - Miguel Cámara
- Centre for Biomolecular Science, School of Life Science, University of Nottingham, Nottingham, United Kingdom
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50
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Lin J, Cheng J, Wang Y, Shen X. The Pseudomonas Quinolone Signal (PQS): Not Just for Quorum Sensing Anymore. Front Cell Infect Microbiol 2018; 8:230. [PMID: 30023354 PMCID: PMC6039570 DOI: 10.3389/fcimb.2018.00230] [Citation(s) in RCA: 141] [Impact Index Per Article: 23.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2018] [Accepted: 06/18/2018] [Indexed: 12/26/2022] Open
Abstract
The Pseudomonas quinolone signal (PQS) has been studied primarily in the context of its role as a quorum-sensing signaling molecule. Recent data suggest, however, that this molecule may also function to mediate iron acquisition, cytotoxicity, outer-membrane vesicle biogenesis, or to exert host immune modulatory activities.
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Affiliation(s)
- Jinshui Lin
- Shaanxi Engineering and Technological Research Center for Conservation and Utilization of Regional Biological Resources, Yan'an University, Yan'an, China.,College of Life Sciences, Yan'an University, Yan'an, China
| | - Juanli Cheng
- Shaanxi Engineering and Technological Research Center for Conservation and Utilization of Regional Biological Resources, Yan'an University, Yan'an, China.,College of Life Sciences, Yan'an University, Yan'an, China
| | - Yao Wang
- Shaanxi Key Laboratory of Agricultural and Environmental Microbiology, College of Life Sciences, Northwest A&F University, Yangling, China.,State Key Laboratory of Crop Stress Biology for Arid Areas, Northwest A&F University, Yangling, China
| | - Xihui Shen
- Shaanxi Key Laboratory of Agricultural and Environmental Microbiology, College of Life Sciences, Northwest A&F University, Yangling, China.,State Key Laboratory of Crop Stress Biology for Arid Areas, Northwest A&F University, Yangling, China
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