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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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Savchenko V, Szamosvári D, Bao Y, Pignitter M, Böttcher T. Biosynthetic flexibility of Pseudomonas aeruginosa leads to hydroxylated 2-alkylquinolones with proinflammatory host response. Commun Chem 2023; 6:138. [PMID: 37400564 DOI: 10.1038/s42004-023-00937-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2023] [Accepted: 06/19/2023] [Indexed: 07/05/2023] Open
Abstract
The human pathogen Pseudomonas aeruginosa produces various 4(1H)-quinolones with diverse functions. Among these, 2-nonyl-4(1H)-quinolone (NQ) and its N-oxide (NQNO) belong to the main metabolites. Their biosynthesis involves substrates from the fatty acid metabolism and we hypothesized that oxidized fatty acids could be responsible for a so far undetected class of metabolites. We developed a divergent synthesis strategy for 2'-hydroxy (2'-OH) and 2'-oxo- substituted quinolones and N-oxides and demonstrated for the first time that 2'-OH-NQ and 2'-OH-NQNO but not the corresponding 2'-oxo compounds are naturally produced by PAO1 and PA14 strains of P. aeruginosa. The main metabolite 2'-OH-NQ is produced even in concentrations comparable to NQ. Exogenous availability of β-hydroxydecanoic acid can further increase the production of 2'-OH-NQ. In contrast to NQ, 2'-OH-NQ potently induced the cytokine IL-8 in a human cell line at 100 nм, suggesting a potential role in host immune modulation.
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Affiliation(s)
- Viktoriia Savchenko
- Faculty of Chemistry, Institute for Biological Chemistry & Centre for Microbiology and Environmental Systems Science, Department of Microbiology and Ecosystems Science, University of Vienna, Josef-Holaubek-Platz 2 (UZA II), 1090, Vienna, Austria
- Vienna Doctoral School in Chemistry (DoSChem), University of Vienna, Währinger Str. 42, 1090, Vienna, Austria
| | - Dávid Szamosvári
- Faculty of Chemistry, Institute for Biological Chemistry & Centre for Microbiology and Environmental Systems Science, Department of Microbiology and Ecosystems Science, University of Vienna, Josef-Holaubek-Platz 2 (UZA II), 1090, Vienna, Austria
| | - Yifan Bao
- Vienna Doctoral School in Chemistry (DoSChem), University of Vienna, Währinger Str. 42, 1090, Vienna, Austria
- Faculty of Chemistry, Institute for Physiological Chemistry, University of Vienna, Josef-Holaubek-Platz 2 (UZA II), 1090, Vienna, Austria
| | - Marc Pignitter
- Faculty of Chemistry, Institute for Physiological Chemistry, University of Vienna, Josef-Holaubek-Platz 2 (UZA II), 1090, Vienna, Austria
| | - Thomas Böttcher
- Faculty of Chemistry, Institute for Biological Chemistry & Centre for Microbiology and Environmental Systems Science, Department of Microbiology and Ecosystems Science, University of Vienna, Josef-Holaubek-Platz 2 (UZA II), 1090, Vienna, Austria.
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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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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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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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Novel Antibiofilm Inhibitor Ginkgetin as an Antibacterial Synergist against Escherichia coli. Int J Mol Sci 2022; 23:ijms23158809. [PMID: 35955943 PMCID: PMC9369100 DOI: 10.3390/ijms23158809] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2022] [Revised: 08/04/2022] [Accepted: 08/06/2022] [Indexed: 11/27/2022] Open
Abstract
As an opportunistic pathogen, Escherichia coli (E. coli) forms biofilm that increases the virulence of bacteria and antibiotic resistance, posing a serious threat to human and animal health. Recently, ginkgetin (Gin) has been discovered to have antiinflammatory, antioxidant, and antitumor properties. In the present study, we evaluated the antibiofilm and antibacterial synergist of Gin against E. coli. Additionally, Alamar Blue assay combined with confocal laser scanning microscope (CLSM) and crystal violet (CV) staining was used to evaluate the effect of antibiofilm and antibacterial synergist against E. coli. Results showed that Gin reduces biofilm formation, exopolysaccharide (EPS) production, and motility against E. coli without limiting its growth and metabolic activity. Furthermore, we identified the inhibitory effect of Gin on AI-2 signaling molecule production, which showed apparent anti-quorum sensing (QS) properties. The qRT-PCR also indicated that Gin reduced the transcription of curli-related genes (csgA, csgD), flagella-formation genes (flhC, flhD, fliC, fliM), and QS-related genes (luxS, lsrB, lsrK, lsrR). Moreover, Gin showed obvious antibacterial synergism to overcome antibiotic resistance in E. coli with marketed antibiotics, including gentamicin, colistin B, and colistin E. These results suggested the potent antibiofilm and novel antibacterial synergist effect of Gin for treating E. coli infections.
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Yan X, Zhang J, Tan H, Liu Z, Jiang K, Tian W, Zheng M, Lin Z, Deng Z, Qu X. A Pair of Atypical KAS III Homologues with Initiation and Elongation Functions Program the Polyketide Biosynthesis in Asukamycin. Angew Chem Int Ed Engl 2022; 61:e202200879. [DOI: 10.1002/anie.202200879] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2022] [Indexed: 11/06/2022]
Affiliation(s)
- Xiaoli Yan
- Key Laboratory of Combinatorial Biosynthesis and Drug Discovery Ministry of Education School of Pharmaceutical Sciences Wuhan University 1 Luojiashan Rd. Wuhan 430071 China
- State Key Laboratory of Microbial Metabolism and School of Life Sciences and Biotechnology Shanghai Jiao Tong University 800 Dongchuan Rd. Shanghai 200240 China
| | - Jun Zhang
- State Key Laboratory of Microbial Metabolism and School of Life Sciences and Biotechnology Shanghai Jiao Tong University 800 Dongchuan Rd. Shanghai 200240 China
| | - Hongqun Tan
- Key Laboratory of Combinatorial Biosynthesis and Drug Discovery Ministry of Education School of Pharmaceutical Sciences Wuhan University 1 Luojiashan Rd. Wuhan 430071 China
| | - Zhihao Liu
- Key Laboratory of Combinatorial Biosynthesis and Drug Discovery Ministry of Education School of Pharmaceutical Sciences Wuhan University 1 Luojiashan Rd. Wuhan 430071 China
| | - Kai Jiang
- State Key Laboratory of Microbial Metabolism and School of Life Sciences and Biotechnology Shanghai Jiao Tong University 800 Dongchuan Rd. Shanghai 200240 China
| | - Wenya Tian
- State Key Laboratory of Microbial Metabolism and School of Life Sciences and Biotechnology Shanghai Jiao Tong University 800 Dongchuan Rd. Shanghai 200240 China
| | - Mengmeng Zheng
- Key Laboratory of Combinatorial Biosynthesis and Drug Discovery Ministry of Education School of Pharmaceutical Sciences Wuhan University 1 Luojiashan Rd. Wuhan 430071 China
| | - Zhi Lin
- State Key Laboratory of Microbial Metabolism and School of Life Sciences and Biotechnology Shanghai Jiao Tong University 800 Dongchuan Rd. Shanghai 200240 China
| | - Zixin Deng
- State Key Laboratory of Microbial Metabolism and School of Life Sciences and Biotechnology Shanghai Jiao Tong University 800 Dongchuan Rd. Shanghai 200240 China
| | - Xudong Qu
- Key Laboratory of Combinatorial Biosynthesis and Drug Discovery Ministry of Education School of Pharmaceutical Sciences Wuhan University 1 Luojiashan Rd. Wuhan 430071 China
- State Key Laboratory of Microbial Metabolism and School of Life Sciences and Biotechnology Shanghai Jiao Tong University 800 Dongchuan Rd. Shanghai 200240 China
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Yan X, Zhang J, Tan H, Liu Z, Jiang K, Tian W, Zheng M, Lin Z, Deng Z, Qu X. A Pair of Atypical KAS III Homologues with Initiation and Elongation Functions Program the Polyketide Biosynthesis in Asukamycin. Angew Chem Int Ed Engl 2022. [DOI: 10.1002/ange.202200879] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Affiliation(s)
- Xiaoli Yan
- Wuhan University School of pharmaceutical Sciences CHINA
| | - Jun Zhang
- Shanghai Jiao Tong University School of Life Sciences and Biotechnology CHINA
| | - Hongqun Tan
- Wuhan University School of Pharmaceutical Sciences CHINA
| | - Zhihao Liu
- Wuhan University School of pharmaceutical Sciences CHINA
| | - Kai Jiang
- Shanghai Jiao Tong University School of Life Sciences and Biotechnology CHINA
| | - Wenya Tian
- Shanghai Jiao Tong University School of Life Sciences and Biotechnology CHINA
| | - Mengmeng Zheng
- Wuhan University School of Pharmaceutical Sciences CHINA
| | - Zhi Lin
- Shanghai Jiao Tong University School of Life Sciences and Biotechnology CHINA
| | - Zixin Deng
- Shanghai Jiao Tong University School of Life Sciences and Biotechnology CHINA
| | - Xudong Qu
- Shanghai Jiao Tong University School of Life Sciences and Biotechnology 800 Dongchuan Rd. 200240 Shanghai CHINA
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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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Chen CM, Chen WH, Pang XY, Liao SR, Wang JF, Lin XP, Yang B, Zhou XF, Luo XW, Liu YH. Pyrrolyl 4-quinolone alkaloids from the mangrove endophytic fungus Penicillium steckii SCSIO 41025: Chiral resolution, configurational assignment, and enzyme inhibitory activities. PHYTOCHEMISTRY 2021; 186:112730. [PMID: 33740577 DOI: 10.1016/j.phytochem.2021.112730] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/08/2020] [Revised: 02/28/2021] [Accepted: 03/06/2021] [Indexed: 06/12/2023]
Abstract
Six undescribed 4-quinolone alkaloids, including four racemic mixtures, (±)-oxypenicinolines A-D, and two related ones, penicinolines F and G, together with seven known analogues, were isolated from the mangrove-derived fungus Penicillium steckii SCSIO 41025 (Trichocomaceae). The racemates were separated by HPLC using chiral columns. Their structures including absolute configurations were elucidated by extensive spectroscopic analysis, electronic circular dichroism (ECD) experiments, and single-crystal X-ray diffraction analysis. Structurally, (±)-oxypenicinolines A-D shared with an unusual 6/6/5/5 tetracyclic system incorporating a rare tetrahydro-pyrrolyl moiety. A plausible biosynthetic pathway for pyrrolyl 4-quinolone alkaloids is proposed. (±)-oxypenicinoline A and quinolactacide displayed α-glucosidase inhibitory activity with the IC50 values of 317.8 and 365.9 μΜ, respectively, which were more potent than that of acarbose (461.0 μM). Additionally, penicinoline and penicinoline E showed weak inhibitions toward acetylcholinesterase (AChE).
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Affiliation(s)
- Chun-Mei Chen
- CAS Key Laboratory of Tropical Marine Bio-resources and Ecology/Guangdong Key Laboratory of Marine Materia Medica, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou, 510301, PR China; University of Chinese Academy of Sciences, Beijing, 100049, PR China
| | - Wei-Hao Chen
- CAS Key Laboratory of Tropical Marine Bio-resources and Ecology/Guangdong Key Laboratory of Marine Materia Medica, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou, 510301, PR China; University of Chinese Academy of Sciences, Beijing, 100049, PR China
| | - Xiao-Yan Pang
- CAS Key Laboratory of Tropical Marine Bio-resources and Ecology/Guangdong Key Laboratory of Marine Materia Medica, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou, 510301, PR China
| | - Sheng-Rong Liao
- CAS Key Laboratory of Tropical Marine Bio-resources and Ecology/Guangdong Key Laboratory of Marine Materia Medica, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou, 510301, PR China; Southern Marine Science and Engineering Guangdong Laboratory (Guangzhou), Guangzhou, 511458, PR China
| | - Jun-Feng Wang
- CAS Key Laboratory of Tropical Marine Bio-resources and Ecology/Guangdong Key Laboratory of Marine Materia Medica, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou, 510301, PR China; Southern Marine Science and Engineering Guangdong Laboratory (Guangzhou), Guangzhou, 511458, PR China
| | - Xiu-Ping Lin
- CAS Key Laboratory of Tropical Marine Bio-resources and Ecology/Guangdong Key Laboratory of Marine Materia Medica, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou, 510301, PR China; Southern Marine Science and Engineering Guangdong Laboratory (Guangzhou), Guangzhou, 511458, PR China
| | - Bin Yang
- CAS Key Laboratory of Tropical Marine Bio-resources and Ecology/Guangdong Key Laboratory of Marine Materia Medica, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou, 510301, PR China; Southern Marine Science and Engineering Guangdong Laboratory (Guangzhou), Guangzhou, 511458, PR China
| | - Xue-Feng Zhou
- CAS Key Laboratory of Tropical Marine Bio-resources and Ecology/Guangdong Key Laboratory of Marine Materia Medica, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou, 510301, PR China; Southern Marine Science and Engineering Guangdong Laboratory (Guangzhou), Guangzhou, 511458, PR China
| | - Xiao-Wei Luo
- Institute of Marine Drugs, Guangxi University of Chinese Medicine, Nanning, 530200, PR China.
| | - Yong-Hong Liu
- CAS Key Laboratory of Tropical Marine Bio-resources and Ecology/Guangdong Key Laboratory of Marine Materia Medica, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou, 510301, PR China; Institute of Marine Drugs, Guangxi University of Chinese Medicine, Nanning, 530200, PR China; Southern Marine Science and Engineering Guangdong Laboratory (Guangzhou), Guangzhou, 511458, PR China; University of Chinese Academy of Sciences, Beijing, 100049, PR China.
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11
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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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12
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Signal Synthase-Type versus Catabolic Monooxygenases: Retracing 3-Hydroxylation of 2-Alkylquinolones and Their N-Oxides by Pseudomonas aeruginosa and Other Pulmonary Pathogens. Appl Environ Microbiol 2021; 87:AEM.02241-20. [PMID: 33452035 DOI: 10.1128/aem.02241-20] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2020] [Accepted: 12/20/2020] [Indexed: 01/18/2023] Open
Abstract
The multiple biological activities of 2-alkylquinolones (AQs) are crucial for virulence of Pseudomonas aeruginosa, conferring advantages during infection and in polymicrobial communities. Whereas 2-heptyl-3-hydroxyquinolin-4(1H)-one (the "Pseudomonas quinolone signal" [PQS]) is an important quorum sensing signal molecule, 2-alkyl-1-hydroxyquinolin-4(1H)-ones (also known as 2-alkyl-4-hydroxyquinoline N-oxides [AQNOs]) are antibiotics inhibiting respiration. Hydroxylation of the PQS precursor 2-heptylquinolin-4(1H)-one (HHQ) by the signal synthase PqsH boosts AQ quorum sensing. Remarkably, the same reaction, catalyzed by the ortholog AqdB, is used by Mycobacteroides abscessus to initiate degradation of AQs. The antibiotic 2-heptyl-1-hydroxyquinolin-4(1H)-one (HQNO) is hydroxylated by Staphylococcus aureus to the less toxic derivative PQS-N-oxide (PQS-NO), a reaction probably also catalyzed by a PqsH/AqdB ortholog. In this study, we provide a comparative analysis of four AQ 3-monooxygenases of different organisms. Due to the major impact of AQ/AQNO 3-hydroxylation on the biological activities of the compounds, we surmised adaptations on the enzymatic and/or physiological level to serve either the producer or target organisms. Our results indicate that all enzymes share similar features and are incapable of discriminating between AQs and AQNOs. PQS-NO, hence, occurs as a native metabolite of P. aeruginosa although the unfavorable AQNO 3-hydroxylation is minimized by export as shown for HQNO, involving at least one multidrug efflux pump. Moreover, M. abscessus is capable of degrading the AQNO heterocycle by concerted action of AqdB and dioxygenase AqdC. However, S. aureus and M. abscessus orthologs disfavor AQNOs despite their higher toxicity, suggesting that catalytic constraints restrict evolutionary adaptation and lead to the preference of non-N-oxide substrates by AQ 3-monooxygenases.IMPORTANCE Pseudomonas aeruginosa, Staphylococcus aureus, and Mycobacteroides abscessus are major players in bacterial chronic infections and particularly common colonizers of cystic fibrosis (CF) lung tissue. Whereas S. aureus is an early onset pathogen in CF, P. aeruginosa establishes at later stages. M. abscessus occurs at all stages but has a lower epidemiological incidence. The dynamics of how these pathogens interact can affect survival and therapeutic success. 2-Alkylquinolone (AQ) and 2-alkylhydroxyquinoline N-oxide (AQNO) production is a major factor of P. aeruginosa virulence. The 3-position of the AQ scaffold is critical, both for attenuation of AQ toxicity or degradation by competitors, as well as for full unfolding of quorum sensing. Despite lacking signaling functionality, AQNOs have the strongest impact on suppression of Gram-positives. Because evidence for 3-hydroxylation of AQNOs has been reported, it is desirable to understand the extent by which AQ 3-monooxygenases contribute to manipulation of AQ/AQNO equilibrium, resistance, and degradation.
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13
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Grossman S, Soukarieh F, Richardson W, Liu R, Mashabi A, Emsley J, Williams P, Cámara M, Stocks MJ. Novel quinazolinone inhibitors of the Pseudomonas aeruginosa quorum sensing transcriptional regulator PqsR. Eur J Med Chem 2020; 208:112778. [PMID: 32927392 PMCID: PMC7684530 DOI: 10.1016/j.ejmech.2020.112778] [Citation(s) in RCA: 24] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2020] [Revised: 08/07/2020] [Accepted: 08/20/2020] [Indexed: 01/14/2023]
Abstract
Rising numbers of cases of multidrug- and extensively drug-resistant Pseudomonas aeruginosa over recent years have created an urgent need for novel therapeutic approaches to cure potentially fatal infections. One such approach is virulence attenuation where anti-virulence compounds, designed to reduce pathogenicity without affording bactericidal effects, are employed to treat infections. P. aeruginosa uses the pqs quorum sensing (QS) system, to coordinate the expression of a large number of virulence determinants as well as bacterial-host interactions and hence represents an excellent anti-virulence target. We report the synthesis and identification of a new series of thiazole-containing quinazolinones capable of inhibiting PqsR, the transcriptional regulator of the pqs QS system. The compounds demonstrated high potency (IC50 < 300 nM) in a whole-cell assay, using a mCTX:PpqsA-lux-based bioreporter for the P. aeruginosa PAO1-L and PA14 strains. Structural evaluation defined the binding modes of four analogues in the ligand-binding domain of PqsR through X-ray crystallography. Further work showed the ability of 6-chloro-3((2-pentylthiazol-4-yl)methyl)quinazolin-4(3H)-one (18) and 6-chloro-3((2-hexylthiazol-4-yl)methyl)quinazolin-4(3H)-one (19) to attenuate production of the PqsR-regulated virulence factor pyocyanin. Compounds 18 and 19 showed a low cytotoxic profile in the A549 human epithelial lung cell line making them suitable candidates for further pre-clinical evaluation.
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Affiliation(s)
- Scott Grossman
- School of Pharmacy, University of Nottingham Biodiscovery Institute, University Park, Nottingham, Nottinghamshire, NG7 2RD, UK
| | - Fadi Soukarieh
- School of Life Sciences, University of Nottingham Biodiscovery Institute, University Park, Nottingham, Nottinghamshire, NG7 2RD, UK; National Biofilms Innovation Centre, University of Nottingham Biodiscovery Institute, University Park, Nottingham, Nottinghamshire, NG7 2RD, UK
| | - William Richardson
- School of Pharmacy, University of Nottingham Biodiscovery Institute, University Park, Nottingham, Nottinghamshire, NG7 2RD, UK
| | - Ruiling Liu
- School of Pharmacy, University of Nottingham Biodiscovery Institute, University Park, Nottingham, Nottinghamshire, NG7 2RD, UK
| | - Alaa Mashabi
- School of Pharmacy, University of Nottingham Biodiscovery Institute, University Park, Nottingham, Nottinghamshire, NG7 2RD, UK
| | - Jonas Emsley
- School of Pharmacy, University of Nottingham Biodiscovery Institute, University Park, Nottingham, Nottinghamshire, NG7 2RD, UK; National Biofilms Innovation Centre, University of Nottingham Biodiscovery Institute, University Park, Nottingham, Nottinghamshire, NG7 2RD, UK
| | - Paul Williams
- School of Life Sciences, University of Nottingham Biodiscovery Institute, University Park, Nottingham, Nottinghamshire, NG7 2RD, UK; National Biofilms Innovation Centre, University of Nottingham Biodiscovery Institute, University Park, Nottingham, Nottinghamshire, NG7 2RD, UK
| | - Miguel Cámara
- School of Life Sciences, University of Nottingham Biodiscovery Institute, University Park, Nottingham, Nottinghamshire, NG7 2RD, UK; National Biofilms Innovation Centre, University of Nottingham Biodiscovery Institute, University Park, Nottingham, Nottinghamshire, NG7 2RD, UK
| | - Michael J Stocks
- School of Pharmacy, University of Nottingham Biodiscovery Institute, University Park, Nottingham, Nottinghamshire, NG7 2RD, UK; National Biofilms Innovation Centre, University of Nottingham Biodiscovery Institute, University Park, Nottingham, Nottinghamshire, NG7 2RD, UK.
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14
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Hu Y, Cronan JE. α-proteobacteria synthesize biotin precursor pimeloyl-ACP using BioZ 3-ketoacyl-ACP synthase and lysine catabolism. Nat Commun 2020; 11:5598. [PMID: 33154364 PMCID: PMC7645780 DOI: 10.1038/s41467-020-19251-5] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2020] [Accepted: 09/28/2020] [Indexed: 11/09/2022] Open
Abstract
Pimelic acid, a seven carbon α,ω-dicarboxylic acid (heptanedioic acid), is known to provide seven of the ten biotin carbon atoms including all those of the valeryl side chain. Distinct pimelate synthesis pathways were recently elucidated in Escherichia coli and Bacillus subtilis where fatty acid synthesis plus dedicated biotin enzymes produce the pimelate moiety. In contrast, the α-proteobacteria which include important plant and mammalian pathogens plus plant symbionts, lack all of the known pimelate synthesis genes and instead encode bioZ genes. Here we report a pathway in which BioZ proteins catalyze a 3-ketoacyl-acyl carrier protein (ACP) synthase III-like reaction to produce pimeloyl-ACP with five of the seven pimelate carbon atoms being derived from glutaryl-CoA, an intermediate in lysine degradation. Agrobacterium tumefaciens strains either deleted for bioZ or which encode a BioZ active site mutant are biotin auxotrophs, as are strains defective in CaiB which catalyzes glutaryl-CoA synthesis from glutarate and succinyl-CoA.
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Affiliation(s)
- Yuanyuan Hu
- Department of Biochemistry, University of Illinois at Urbana-Champaign, Urbana, IL, USA
| | - John E Cronan
- Department of Microbiology, University of Illinois at Urbana-Champaign, Urbana, IL, USA.
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15
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Quantitative proteomic reveals gallium maltolate induces an iron-limited stress response and reduced quorum-sensing in Pseudomonas aeruginosa. J Biol Inorg Chem 2020; 25:1153-1165. [DOI: 10.1007/s00775-020-01831-x] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2020] [Accepted: 10/21/2020] [Indexed: 01/12/2023]
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16
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Shao X, Xie Y, Zhang Y, Liu J, Ding Y, Wu M, Wang X, Deng X. Novel therapeutic strategies for treating Pseudomonas aeruginosa infection. Expert Opin Drug Discov 2020; 15:1403-1423. [PMID: 32880507 DOI: 10.1080/17460441.2020.1803274] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
INTRODUCTION Persistent infections caused by the superbug Pseudomonas aeruginosa and its resistance to multiple antimicrobial agents are huge threats to patients with cystic fibrosis as well as those with compromised immune systems. Multidrug-resistant P. aeruginosa has posed a major challenge to conventional antibiotics and therapeutic approaches, which show limited efficacy and cause serious side effects. The public demand for new antibiotics is enormous; yet, drug development pipelines have started to run dry with limited targets available for inventing new antibacterial drugs. Consequently, it is important to uncover potential therapeutic targets. AREAS COVERED The authors review the current state of drug development strategies that are promising in terms of the development of novel and potent drugs to treat P. aeruginosa infection. EXPERT OPINION The prevention of P. aeruginosa infection is increasingly challenging. Furthermore, targeting key virulence regulators has great potential for developing novel anti-P. aeruginosa drugs. Additional promising strategies include bacteriophage therapy, immunotherapies, and antimicrobial peptides. Additionally, the authors believe that in the coming years, the overall network of molecular regulatory mechanism of P. aeruginosa virulence will be fully elucidated, which will provide more novel and promising drug targets for treating P. aeruginosa infections.
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Affiliation(s)
- Xiaolong Shao
- Department of Biomedical Sciences, City University of Hong Kong , Hong Kong SAR, China
| | - Yingpeng Xie
- Department of Biomedical Sciences, City University of Hong Kong , Hong Kong SAR, China
| | - Yingchao Zhang
- Department of Biomedical Sciences, City University of Hong Kong , Hong Kong SAR, China
| | - Jingui Liu
- Department of Biomedical Sciences, City University of Hong Kong , Hong Kong SAR, China
| | - Yiqing Ding
- Department of Biomedical Sciences, City University of Hong Kong , Hong Kong SAR, China
| | - Min Wu
- Department of Biomedical Sciences, University of North Dakota , Grand Forks, North Dakota, USA
| | - Xin Wang
- Department of Biomedical Sciences, City University of Hong Kong , Hong Kong SAR, China
| | - Xin Deng
- Department of Biomedical Sciences, City University of Hong Kong , Hong Kong SAR, China.,Shenzhen Research Institute, City University of Hong Kong , Shenzhen, China
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17
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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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18
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Photoinduced monooxygenation involving NAD(P)H-FAD sequential single-electron transfer. Nat Commun 2020; 11:2600. [PMID: 32451409 PMCID: PMC7248105 DOI: 10.1038/s41467-020-16450-y] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2019] [Accepted: 04/28/2020] [Indexed: 01/09/2023] Open
Abstract
Light-dependent or light-stimulated catalysis provides a multitude of perspectives for implementation in technological or biomedical applications. Despite substantial progress made in the field of photobiocatalysis, the number of usable light-responsive enzymes is still very limited. Flavoproteins have exceptional potential for photocatalytic applications because the name-giving cofactor intrinsically features light-dependent reactivity, undergoing photoreduction with a variety of organic electron donors. However, in the vast majority of these enzymes, photoreactivity of the enzyme-bound flavin is limited or even suppressed. Here, we present a flavoprotein monooxygenase in which catalytic activity is controllable by blue light illumination. The reaction depends on the presence of nicotinamide nucleotide-type electron donors, which do not support the reaction in the absence of light. Employing various experimental approaches, we demonstrate that catalysis depends on a protein-mediated photoreduction of the flavin cofactor, which proceeds via a radical mechanism and a transient semiquinone intermediate.
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19
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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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20
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Abstract
Enzyme inhibitors are central tools for chemical biology. In this chapter we will discuss the application of chemical probes for competitive profiling of inhibitors of the quinolone biosynthesis enzyme PqsD of Pseudomonas aeruginosa. The human pathogen P. aeruginosa produces a large diversity of 2-alkyl-4(1H)-quinolones and their derivatives as metabolites with major roles in quorum sensing, virulence, and interspecies competition. PqsD is a central enzyme in the biosynthesis of all of these quinolones and hence an interesting target for inhibitor discovery. Activity-based probes with an electrophilic warhead bind covalently to active site nucleophiles like cysteine or serine. An α-chloroacetamide probe with terminal alkyne tag allowed to selectively label the active site cysteine of PqsD and was demonstrated to be a useful tool for inhibitor discovery using competition experiments. Potent inhibitors bind to the active site and thereby prevent labeling of the enzyme by the probe. Labeling intensity is quantified on polyacrylamide gels by the fluorescence of a reporter tag appended by bioorthogonal click chemistry. The competitive inhibitor profiling strategy has many advantages over traditional screening approaches and is applicable in vitro as well as in live cells. Here we describe the synthesis of an activity-based probe and provide our detailed protocols for target enzyme labeling as well as its application for the screening for potent enzyme inhibitors of PqsD by a competitive profiling strategy.
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Affiliation(s)
- Michaela Prothiwa
- Department of Chemistry, Konstanz Research School Chemical Biology, Zukunftskolleg, University of Konstanz, Konstanz, Germany
| | - Thomas Böttcher
- Department of Chemistry, Konstanz Research School Chemical Biology, Zukunftskolleg, University of Konstanz, Konstanz, Germany.
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21
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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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22
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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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23
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Ritzmann NH, Mährlein A, Ernst S, Hennecke U, Drees SL, Fetzner S. Bromination of alkyl quinolones by Microbulbifer sp. HZ11, a marine Gammaproteobacterium, modulates their antibacterial activity. Environ Microbiol 2019; 21:2595-2609. [PMID: 31087606 DOI: 10.1111/1462-2920.14654] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2019] [Revised: 04/24/2019] [Accepted: 05/10/2019] [Indexed: 01/12/2023]
Abstract
Alkyl quinolones (AQs) are multifunctional bacterial secondary metabolites generally known for their antibacterial and algicidal properties. Certain representatives are also employed as signalling molecules of Burkholderia strains and Pseudomonas aeruginosa. The marine Gammaproteobacterium Microbulbifer sp. HZ11 harbours an AQ biosynthetic gene cluster with unusual topology but does not produce any AQ-type metabolites under laboratory conditions. In this study, we demonstrate the potential of strain HZ11 for AQ production by analysing intermediates and key enzymes of the pathway. Moreover, we demonstrate that exogenously added AQs such as 2-heptyl-1(H)-quinolin-4-one (referred to as HHQ) or 2-heptyl-1-hydroxyquinolin-4-one (referred to as HQNO) are brominated by a vanadium-dependent haloperoxidase (V-HPOHZ11 ), which preferably is active towards AQs with C5-C9 alkyl side chains. Bromination was specific for the third position and led to 3-bromo-2-heptyl-1(H)-quinolin-4-one (BrHHQ) and 3-bromo-2-heptyl-1-hydroxyquinolin-4-one (BrHQNO), both of which were less toxic for strain HZ11 than the respective parental compounds. In contrast, BrHQNO showed increased antibiotic activity against Staphylococcus aureus and marine isolates. Therefore, bromination of AQs by V-HPOHZ11 can have divergent consequences, eliciting a detoxifying effect for strain HZ11 while simultaneously enhancing antibiotic activity against other bacteria.
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Affiliation(s)
- Niklas H Ritzmann
- Institute for Molecular Microbiology and Biotechnology, University of Münster, Münster, Germany
| | - Almuth Mährlein
- Institute for Molecular Microbiology and Biotechnology, University of Münster, Münster, Germany
| | - Simon Ernst
- Institute for Molecular Microbiology and Biotechnology, University of Münster, Münster, Germany
| | - Ulrich Hennecke
- Organic Chemistry Institute, University of Münster, Münster, Germany.,Organic Chemistry Research Group, Department of Chemistry and Department of Bioengineering Sciences, Vrije Universiteit Brussel, Brussel, Belgium
| | - Steffen L Drees
- Institute for Molecular Microbiology and Biotechnology, University of Münster, Münster, Germany
| | - Susanne Fetzner
- Institute for Molecular Microbiology and Biotechnology, University of Münster, Münster, Germany
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24
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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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25
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Nofiani R, Philmus B, Nindita Y, Mahmud T. 3-Ketoacyl-ACP synthase (KAS) III homologues and their roles in natural product biosynthesis. MEDCHEMCOMM 2019; 10:1517-1530. [PMID: 31673313 DOI: 10.1039/c9md00162j] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/15/2019] [Accepted: 04/29/2019] [Indexed: 11/21/2022]
Abstract
The 3-ketoacyl-ACP synthase (KAS) III proteins are one of the most abundant enzymes in nature, as they are involved in the biosynthesis of fatty acids and natural products. KAS III enzymes catalyse a carbon-carbon bond formation reaction that involves the α-carbon of a thioester and the carbonyl carbon of another thioester. In addition to the typical KAS III enzymes involved in fatty acid and polyketide biosynthesis, there are proteins homologous to KAS III enzymes that catalyse reactions that are different from that of the traditional KAS III enzymes. Those include enzymes that are responsible for a head-to-head condensation reaction, the formation of acetoacetyl-CoA in mevalonate biosynthesis, tailoring processes via C-O bond formation or esterification, as well as amide formation. This review article highlights the diverse reactions catalysed by this class of enzymes and their role in natural product biosynthesis.
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Affiliation(s)
- Risa Nofiani
- Department of Pharmaceutical Sciences , Oregon State University , Corvallis , OR 97333 , USA . .,Department of Chemistry , Universitas Tanjungpura , Pontianak , Indonesia
| | - Benjamin Philmus
- Department of Pharmaceutical Sciences , Oregon State University , Corvallis , OR 97333 , USA .
| | - Yosi Nindita
- Department of Pharmaceutical Sciences , Oregon State University , Corvallis , OR 97333 , USA .
| | - Taifo Mahmud
- Department of Pharmaceutical Sciences , Oregon State University , Corvallis , OR 97333 , USA .
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26
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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: 145] [Impact Index Per Article: 29.0] [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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27
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Anti-PqsR compounds as next-generation antibacterial agents against Pseudomonas aeruginosa: A review. Eur J Med Chem 2019; 172:26-35. [PMID: 30939351 DOI: 10.1016/j.ejmech.2019.03.049] [Citation(s) in RCA: 38] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2018] [Revised: 03/19/2019] [Accepted: 03/19/2019] [Indexed: 01/31/2023]
Abstract
Nowadays, due to spreading antibiotic resistance among clinically relevant pathogens, the requirement of novel therapeutic approaches is felt more than ever. One of the alternative strategies is anti-virulence therapy without affecting bacterial growth or viability. In Pseudomonas aeruginosa, an opportunistic human pathogen that exhibits intrinsic multi-drug resistance, both virulence factors' production and biofilm formation depends on its quorum sensing (QS) network. Therefore, targeting the key proteins involved in QS system is an attractive method to overcome P. aeruginosa pathogenicity and resistance. The transcriptional regulator PqsR, also called MvfR, is one of these major proteins which employs 3,4-dihydroxy-2-heptylquinoline (PQS) and 4-hydroxy-2-heptylquinoline (HHQ) as signaling molecules. Reviewing the advances in development of small molecules inhibit this protein, assist to open a new window to smart molecule design that may revolutionize treatment of P. aeruginosa infections.
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28
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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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29
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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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30
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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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31
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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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32
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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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33
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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: 84] [Impact Index Per Article: 14.0] [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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34
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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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35
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Witzgall F, Depke T, Hoffmann M, Empting M, Brönstrup M, Müller R, Blankenfeldt W. The Alkylquinolone Repertoire of Pseudomonas aeruginosa is Linked to Structural Flexibility of the FabH-like 2-Heptyl-3-hydroxy-4(1H)-quinolone (PQS) Biosynthesis Enzyme PqsBC. Chembiochem 2018; 19:1531-1544. [PMID: 29722462 DOI: 10.1002/cbic.201800153] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2018] [Indexed: 12/22/2022]
Abstract
Pseudomonas aeruginosa is a bacterial pathogen that causes life-threatening infections in immunocompromised patients. It produces a large armory of saturated and mono-unsaturated 2-alkyl-4(1H)-quinolones (AQs) and AQ N-oxides (AQNOs) that serve as signaling molecules to control the production of virulence factors and that are involved in membrane vesicle formation and iron chelation; furthermore, they also have, for example, antibiotic properties. It has been shown that the β-ketoacyl-acyl-carrier protein synthase III (FabH)-like heterodimeric enzyme PqsBC catalyzes the last step in the biosynthesis of the most abundant AQ congener, 2-heptyl-4(1H)-quinolone (HHQ), by condensing octanoyl-coenzyme A (CoA) with 2-aminobenzoylacetate (2-ABA), but the basis for the large number of other AQs/AQNOs produced by P. aeruginosa is not known. Here, we demonstrate that PqsBC uses different medium-chain acyl-CoAs to produce various saturated AQs/AQNOs and that it also biosynthesizes mono-unsaturated congeners. Further, we determined the structures of PqsBC in four different crystal forms at 1.5 to 2.7 Å resolution. Together with a previous report, the data reveal that PqsBC adopts open, intermediate, and closed conformations that alter the shape of the acyl-binding cavity and explain the promiscuity of PqsBC. The different conformations also allow us to propose a model for structural transitions that accompany the catalytic cycle of PqsBC that might have broader implications for other FabH-enzymes, for which such structural transitions have been postulated but have never been observed.
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Affiliation(s)
- Florian Witzgall
- Department Structure and Function of Proteins, Helmholtz Centre for Infection Research, Inhoffenstrasse 7, 38124, Braunschweig, Germany
| | - Tobias Depke
- Department Chemical Biology, Helmholtz Centre for Infection Research, Inhoffenstrasse 7, 38124, Braunschweig, Germany
| | - Michael Hoffmann
- Department Microbial Natural Products, Helmholtz Institute for Pharmaceutical Research Saarland, Helmholtz Centre for Infection Research, Campus E8.1, 66123, Saarbrücken, Germany.,Department of Pharmacy, Saarland University, Campus E8.1, 66123, Saarbrücken, Germany
| | - Martin Empting
- Department Drug Design and Optimization, Helmholtz Institute for Pharmaceutical Research Saarland, Helmholtz Centre for Infection Research, Campus E8.1, 66123, Saarbrücken, Germany.,Department of Pharmacy, Saarland University, Campus E8.1, 66123, Saarbrücken, Germany
| | - Mark Brönstrup
- Department Chemical Biology, Helmholtz Centre for Infection Research, Inhoffenstrasse 7, 38124, Braunschweig, Germany
| | - Rolf Müller
- Department Microbial Natural Products, Helmholtz Institute for Pharmaceutical Research Saarland, Helmholtz Centre for Infection Research, Campus E8.1, 66123, Saarbrücken, Germany.,Department of Pharmacy, Saarland University, Campus E8.1, 66123, Saarbrücken, Germany
| | - Wulf Blankenfeldt
- Department Structure and Function of Proteins, Helmholtz Centre for Infection Research, Inhoffenstrasse 7, 38124, Braunschweig, Germany.,Institute for Biochemistry, Biotechnology and Bioinformatics, Technische Universität Braunschweig, Spielmannstrasse 7, 38106, Braunschweig, Germany
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36
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Uddin R, Jamil F. Prioritization of potential drug targets against P. aeruginosa by core proteomic analysis using computational subtractive genomics and Protein-Protein interaction network. Comput Biol Chem 2018; 74:115-122. [DOI: 10.1016/j.compbiolchem.2018.02.017] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2017] [Revised: 01/06/2018] [Accepted: 02/22/2018] [Indexed: 01/12/2023]
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37
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Drees SL, Ernst S, Belviso BD, Jagmann N, Hennecke U, Fetzner S. PqsL uses reduced flavin to produce 2-hydroxylaminobenzoylacetate, a preferred PqsBC substrate in alkyl quinolone biosynthesis in Pseudomonas aeruginosa. J Biol Chem 2018; 293:9345-9357. [PMID: 29669807 DOI: 10.1074/jbc.ra117.000789] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2017] [Revised: 04/06/2018] [Indexed: 01/05/2023] Open
Abstract
Alkyl hydroxyquinoline N-oxides (AQNOs) are antibiotic compounds produced by the opportunistic bacterial pathogen Pseudomonas aeruginosa They are products of the alkyl quinolone (AQ) biosynthetic pathway, which also generates the quorum-sensing molecules 2-heptyl-4(1H)-quinolone (HHQ) and 2-heptyl-3-hydroxy-4(1H)-quinolone (PQS). Although the enzymatic synthesis of HHQ and PQS had been elucidated, the route by which AQNOs are synthesized remained elusive. Here, we report on PqsL, the key enzyme for AQNO production, which structurally resembles class A flavoprotein monooxygenases such as p-hydroxybenzoate 3-hydroxylase (pHBH) and 3-hydroxybenzoate 6-hydroxylase. However, we found that unlike related enzymes, PqsL hydroxylates a primary aromatic amine group, and it does not use NAD(P)H as cosubstrate, but unexpectedly required reduced flavin as electron donor. We also observed that PqsL is active toward 2-aminobenzoylacetate (2-ABA), the central intermediate of the AQ pathway, and forms the unstable compound 2-hydroxylaminobenzoylacetate, which was preferred over 2-ABA as substrate of the downstream enzyme PqsBC. In vitro reconstitution of the PqsL/PqsBC reaction was feasible by using the FAD reductase HpaC, and we noted that the AQ:AQNO ratio is increased in an hpaC-deletion mutant of P. aeruginosa PAO1 compared with the ratio in the WT strain. A structural comparison with pHBH, the model enzyme of class A flavoprotein monooxygenases, revealed that structural features associated with NAD(P)H binding are missing in PqsL. Our study completes the AQNO biosynthetic pathway in P. aeruginosa, indicating that PqsL produces the unstable product 2-hydroxylaminobenzoylacetate from 2-ABA and depends on free reduced flavin as electron donor instead of NAD(P)H.
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Affiliation(s)
| | - Simon Ernst
- From the Institute for Molecular Microbiology and Biotechnology and
| | - Benny Danilo Belviso
- the Institute of Crystallography, Consiglio Nazionale delle Ricerche, 70126 Bari, Italy
| | - Nina Jagmann
- From the Institute for Molecular Microbiology and Biotechnology and
| | - Ulrich Hennecke
- Organic Chemistry Institute, University of Münster, D-48149 Münster, Germany and
| | - Susanne Fetzner
- From the Institute for Molecular Microbiology and Biotechnology and
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38
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Leichnitz D, Raguž L, Beemelmanns C. Total synthesis and functional analysis of microbial signalling molecules. Chem Soc Rev 2018; 46:6330-6344. [PMID: 28902198 DOI: 10.1039/c6cs00665e] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Communication is essential for all domains of life. Bacteria use a plethora of small molecules to sense and orchestrate intra- and interspecies communication. Within this review, we will discuss different groups of signalling molecules, including autoinducers, virulence factors and morphogenic substances. On selected examples, we will shortly discuss their ecological roles and biosynthetic proposals. The major part of this review will focus on a systematic overview of the different synthetic methods applied towards the synthesis of signalling molecules and derivatives thereof. The described examples highlight the importance of organic synthetic method development and diversity-oriented total syntheses for structure verification, structure-function analysis and target identification.
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Affiliation(s)
- D Leichnitz
- Leibniz Institute for Natural Product Research and Infection Biology - Hans Knöll Institute, Beutenbergstraße 11a, D-07745 Jena, Germany.
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39
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Lee WC, Jeong MC, Lee Y, Kwak C, Lee JY, Kim Y. Structure and substrate specificity of β-ketoacyl-acyl carrier protein synthase III from Acinetobacter baumannii. Mol Microbiol 2018. [PMID: 29528170 DOI: 10.1111/mmi.13950] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Originally annotated as the initiator of fatty acid synthesis (FAS), β-ketoacyl-acyl carrier protein synthase III (KAS III) is a unique component of the bacterial FAS system. Novel variants of KAS III have been identified that promote the de novo use of additional extracellular fatty acids by FAS. These KAS III variants prefer longer acyl-groups, notably octanoyl-CoA. Acinetobacter baumannii, a clinically important nosocomial pathogen, contains such a multifunctional KAS III (AbKAS III). To characterize the structural basis of its substrate specificity, we determined the crystal structures of AbKAS III in the presence of different substrates. The acyl-group binding cavity of AbKAS III and co-crystal structure of AbKAS III and octanoyl-CoA confirmed that the cavity can accommodate acyl groups with longer alkyl chains. Interestingly, Cys264 formed a disulfide bond with residual CoA used in the crystallization, which distorted helices at the putative interface with acyl-carrier proteins. The crystal structure of KAS III in the alternate conformation can also be utilized for designing novel antibiotics.
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Affiliation(s)
- Woo Cheol Lee
- Department of Bioscience and Biotechnology, Konkuk University, Seoul 05029, Republic of Korea
| | - Min-Cheol Jeong
- Department of Bioscience and Biotechnology, Konkuk University, Seoul 05029, Republic of Korea
| | - Yeongjoon Lee
- Department of Bioscience and Biotechnology, Konkuk University, Seoul 05029, Republic of Korea
| | - Chulhee Kwak
- Department of Bioscience and Biotechnology, Konkuk University, Seoul 05029, Republic of Korea
| | - Jee-Young Lee
- New Drug Development Center, Daegu-Gyeongbuk Medical Innovation Foundation (DGMIF), Daegu 41061, Republic of Korea
| | - Yangmee Kim
- Department of Bioscience and Biotechnology, Konkuk University, Seoul 05029, Republic of Korea
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40
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Szamosvári D, Rütschlin S, Böttcher T. From pirates and killers: does metabolite diversity drive bacterial competition? Org Biomol Chem 2018. [DOI: 10.1039/c8ob00150b] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
This article discusses interspecies competition by sets of closely related metabolites with significantly different biological activities.
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Affiliation(s)
- Dávid Szamosvári
- Department of Chemistry
- Konstanz Research School Chemical Biology
- University of Konstanz
- 78457 Konstanz
- Germany
| | - Sina Rütschlin
- Department of Chemistry
- Konstanz Research School Chemical Biology
- University of Konstanz
- 78457 Konstanz
- Germany
| | - Thomas Böttcher
- Department of Chemistry
- Konstanz Research School Chemical Biology
- University of Konstanz
- 78457 Konstanz
- Germany
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41
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Witzgall F, Ewert W, Blankenfeldt W. Structures of the N-Terminal Domain of PqsA in Complex with Anthraniloyl- and 6-Fluoroanthraniloyl-AMP: Substrate Activation in Pseudomonas Quinolone Signal (PQS) Biosynthesis. Chembiochem 2017; 18:2045-2055. [PMID: 28834007 DOI: 10.1002/cbic.201700374] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2017] [Indexed: 12/16/2022]
Abstract
Pseudomonas aeruginosa, a prevalent pathogen in nosocomial infections and a major burden in cystic fibrosis, uses three interconnected quorum-sensing systems to coordinate virulence processes. At variance with other Gram-negative bacteria, one of these systems relies on 2-alkyl-4(1H)-quinolones (Pseudomonas quinolone signal, PQS) and might hence be an attractive target for new anti-infective agents. Here we report crystal structures of the N-terminal domain of anthranilate-CoA ligase PqsA, the first enzyme of PQS biosynthesis, in complex with anthraniloyl-AMP and with 6-fluoroanthraniloyl-AMP (6FABA-AMP) at 1.4 and 1.7 Å resolution. We find that PqsA belongs to an unrecognized subfamily of anthranilate-CoA ligases that recognize the amino group of anthranilate through a water-mediated hydrogen bond. The complex with 6FABA-AMP explains why 6FABA, an inhibitor of PQS biosynthesis, is a good substrate of PqsA. Together, our data might pave a way to new pathoblockers in P. aeruginosa infections.
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Affiliation(s)
- Florian Witzgall
- Structure and Function of Proteins, Helmholtz Centre for Infection Research, Inhoffenstrasse 7, 38124, Braunschweig, Germany
| | - Wiebke Ewert
- Structure and Function of Proteins, Helmholtz Centre for Infection Research, Inhoffenstrasse 7, 38124, Braunschweig, Germany.,Institut für Biophysikalische Chemie, Medizinische Hochschule Hannover, Carl-Neuberg-Strasse 1, 30625, Hannover, Germany
| | - Wulf Blankenfeldt
- Structure and Function of Proteins, Helmholtz Centre for Infection Research, Inhoffenstrasse 7, 38124, Braunschweig, Germany.,Institut für Biochemie, Biotechnologie und Bioinformatik, Technische Universität Braunschweig, Spielmannstrasse 7, 38106, Braunschweig, Germany
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42
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Bandyopadhaya A, Tsurumi A, Rahme LG. NF-κBp50 and HDAC1 Interaction Is Implicated in the Host Tolerance to Infection Mediated by the Bacterial Quorum Sensing Signal 2-Aminoacetophenone. Front Microbiol 2017; 8:1211. [PMID: 28713342 PMCID: PMC5492500 DOI: 10.3389/fmicb.2017.01211] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2017] [Accepted: 06/14/2017] [Indexed: 12/11/2022] Open
Abstract
Some bacterial quorum sensing (QS) small molecules are important mediators of inter-kingdom signaling and impact host immunity. The QS regulated small volatile molecule 2-aminoacetophenone (2-AA), which has been proposed as a biomarker of Pseudomonas aeruginosa colonization in chronically infected human tissues, is critically involved in “host tolerance training” that involves a distinct molecular mechanism of host chromatin regulation through histone deacetylase (HDAC)1. 2-AA’s epigenetic reprogramming action enables host tolerance to high bacterial burden and permits long-term presence of P. aeruginosa without compromising host survival. Here, to further elucidate the molecular mechanisms of 2-AA-mediated host tolerance/resilience we investigated the connection between histone acetylation status and nuclear factor (NF)-κB signaling components that together coordinate 2-AA-mediated control of transcriptional activity. We found increased NF-κBp65 acetylation levels in 2-AA stimulated cells that are preceded by association of CBP/p300 and increased histone acetyltransferase activity. In contrast, in 2-AA-tolerized cells the protein–protein interaction between p65 and CBP/p300 is disrupted and conversely, the interaction between p50 and co-repressor HDAC1 is enhanced, leading to repression of the pro-inflammatory response. These results highlight how a bacterial QS signaling molecule can establish a link between intracellular signaling and epigenetic reprogramming of pro-inflammatory mediators that may contribute to host tolerance training. These new insights might contribute to the development of novel therapeutic interventions against bacterial infections.
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Affiliation(s)
- Arunava Bandyopadhaya
- Department of Surgery, Massachusetts General Hospital and Harvard Medical School, BostonMA, United States.,Department of Microbiology and Immunobiology, Harvard Medical School, BostonMA, United States.,Shriners Hospitals for Children Boston, BostonMA, United States
| | - Amy Tsurumi
- Department of Surgery, Massachusetts General Hospital and Harvard Medical School, BostonMA, United States.,Department of Microbiology and Immunobiology, Harvard Medical School, BostonMA, United States.,Shriners Hospitals for Children Boston, BostonMA, United States
| | - Laurence G Rahme
- Department of Surgery, Massachusetts General Hospital and Harvard Medical School, BostonMA, United States.,Department of Microbiology and Immunobiology, Harvard Medical School, BostonMA, United States.,Shriners Hospitals for Children Boston, BostonMA, United States
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43
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Allegretta G, Maurer CK, Eberhard J, Maura D, Hartmann RW, Rahme L, Empting M. In-depth Profiling of MvfR-Regulated Small Molecules in Pseudomonas aeruginosa after Quorum Sensing Inhibitor Treatment. Front Microbiol 2017; 8:924. [PMID: 28596760 PMCID: PMC5442231 DOI: 10.3389/fmicb.2017.00924] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2017] [Accepted: 05/08/2017] [Indexed: 01/02/2023] Open
Abstract
Pseudomonas aeruginosa is a Gram-negative bacterium, which causes opportunistic infections in immuno-compromised individuals. Due to its multiple resistances toward antibiotics, the development of new drugs is required. Interfering with Quorum Sensing (QS), a cell-to-cell communication system, has shown to be highly efficient in reducing P. aeruginosa pathogenicity. One of its QS systems employs Pseudomonas Quinolone Signal (PQS) and 4-hydroxy-2-heptylquinoline (HHQ) as signal molecules. Both activate the transcriptional regulator MvfR (Multiple Virulence Factor Regulator), also called PqsR, driving the production of QS molecules as well as toxins and biofilm formation. The aim of this work was to elucidate the effects of QS inhibitors (QSIs), such as MvfR antagonists and PqsBC inhibitors, on the biosynthesis of the MvfR-regulated small molecules 2′-aminoacetophenone (2-AA), dihydroxyquinoline (DHQ), HHQ, PQS, and 4-hydroxy-2-heptylquinoline-N-oxide (HQNO). The employed synthetic MvfR antagonist fully inhibited pqs small molecule formation showing expected sigmoidal dose-response curves for 2-AA, HQNO, HHQ and PQS. Surprisingly, DHQ levels were enhanced at lower antagonist concentrations followed by a full suppression at higher QSI amounts. This particular bi-phasic profile hinted at the accumulation of a biosynthetic intermediate resulting in the observed overproduction of the shunt product DHQ. Additionally, investigations on PqsBC inhibitors showed a reduction of MvfR natural ligands, while increased 2-AA, DHQ and HQNO levels compared to the untreated cells were detected. Moreover, PqsBC inhibitors did not show any significant effect in PA14 pqsC mutant demonstrating their target selectivity. As 2-AA is important for antibacterial tolerance, the QSIs were evaluated in their capability to attenuate persistence. Indeed, persister cells were reduced along with 2-AA inhibition resulting from MvfR antagonism, but not from PqsBC inhibition. In conclusion, antagonizing MvfR using a dosage capable of fully suppressing this QS system will lead to a favorable therapeutic outcome as DHQ overproduction is avoided and bacterial persistence is reduced.
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Affiliation(s)
- Giuseppe Allegretta
- Department of Drug Design and Optimization, Helmholtz Institute for Pharmaceutical Research SaarlandSaarbrücken, Germany
| | - Christine K Maurer
- Department of Drug Design and Optimization, Helmholtz Institute for Pharmaceutical Research SaarlandSaarbrücken, Germany
| | - Jens Eberhard
- Department of Drug Design and Optimization, Helmholtz Institute for Pharmaceutical Research SaarlandSaarbrücken, Germany
| | - Damien Maura
- Department of Surgery and Department of Microbiology and Immunobiology, Harvard Medical School, BostonMA, United States.,Department of Surgery, Center for Surgery, Innovation and Bioengineering, Massachusetts General Hospital, BostonMA, United States.,Shriners Hospitals for Children, BostonMA, United States
| | - Rolf W Hartmann
- Department of Drug Design and Optimization, Helmholtz Institute for Pharmaceutical Research SaarlandSaarbrücken, Germany.,Pharmaceutical and Medicinal Chemistry, Saarland UniversitySaarbrücken, Germany
| | - Laurence Rahme
- Department of Surgery and Department of Microbiology and Immunobiology, Harvard Medical School, BostonMA, United States.,Department of Surgery, Center for Surgery, Innovation and Bioengineering, Massachusetts General Hospital, BostonMA, United States.,Shriners Hospitals for Children, BostonMA, United States
| | - Martin Empting
- Department of Drug Design and Optimization, Helmholtz Institute for Pharmaceutical Research SaarlandSaarbrücken, Germany
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44
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Maura D, Drees SL, Bandyopadhaya A, Kitao T, Negri M, Starkey M, Lesic B, Milot S, Déziel E, Zahler R, Pucci M, Felici A, Fetzner S, Lépine F, Rahme LG. Polypharmacology Approaches against the Pseudomonas aeruginosa MvfR Regulon and Their Application in Blocking Virulence and Antibiotic Tolerance. ACS Chem Biol 2017; 12:1435-1443. [PMID: 28379691 DOI: 10.1021/acschembio.6b01139] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Pseudomonas aeruginosa is an important nosocomial pathogen that is frequently recalcitrant to available antibiotics, underlining the urgent need for alternative therapeutic options against this pathogen. Targeting virulence functions is a promising alternative strategy as it is expected to generate less-selective resistance to treatment compared to antibiotics. Capitalizing on our nonligand-based benzamide-benzimidazole (BB) core structure compounds reported to efficiently block the activity of the P. aeruginosa multiple virulence factor regulator MvfR, here we report the first class of inhibitors shown to interfere with PqsBC enzyme activity, responsible for the synthesis of the MvfR activating ligands HHQ and PQS, and the first to target simultaneously MvfR and PqsBC activity. The use of these compounds reveals that inhibiting PqsBC is sufficient to block P. aeruginosa's acute virulence functions, as the synthesis of MvfR ligands is inhibited. Our results show that MvfR remains the best target of this QS pathway, as we show that antagonists of this target block both acute and persistence-related functions. The structural properties of the compounds reported in this study provide several insights that are instrumental for the design of improved MvfR regulon inhibitors against both acute and persistent P. aeruginosa infections. Moreover, the data presented offer the possibility of a polypharmacology approach of simultaneous silencing two targets in the same pathway. Such a combined antivirulence strategy holds promise in increasing therapeutic efficacy and providing alternatives in the event of a single target's resistance development.
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Affiliation(s)
- Damien Maura
- Shriners Hospitals for Children Boston, Boston, Massachusetts 02114, United States
| | - Steffen L. Drees
- Institute
for Molecular Microbiology and Biotechnology, University of Münster, 48149 Münster, Germany
| | | | - Tomoe Kitao
- Shriners Hospitals for Children Boston, Boston, Massachusetts 02114, United States
| | | | - Melissa Starkey
- Shriners Hospitals for Children Boston, Boston, Massachusetts 02114, United States
| | - Biliana Lesic
- Shriners Hospitals for Children Boston, Boston, Massachusetts 02114, United States
| | - Sylvain Milot
- INRS Institut Armand Frappier, Laval, Quebec H7V 1B7, Canada
| | - Eric Déziel
- INRS Institut Armand Frappier, Laval, Quebec H7V 1B7, Canada
| | - Robert Zahler
- Spero Therapeutics, Cambridge, Massachusetts 02139, United States
| | - Mike Pucci
- Spero Therapeutics, Cambridge, Massachusetts 02139, United States
| | | | - Susanne Fetzner
- Institute
for Molecular Microbiology and Biotechnology, University of Münster, 48149 Münster, Germany
| | - François Lépine
- INRS Institut Armand Frappier, Laval, Quebec H7V 1B7, Canada
| | - Laurence G. Rahme
- Shriners Hospitals for Children Boston, Boston, Massachusetts 02114, United States
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45
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Matsui T, Kodama T, Mori T, Tadakoshi T, Noguchi H, Abe I, Morita H. 2-Alkylquinolone alkaloid biosynthesis in the medicinal plant Evodia rutaecarpa involves collaboration of two novel type III polyketide synthases. J Biol Chem 2017; 292:9117-9135. [PMID: 28411241 DOI: 10.1074/jbc.m117.778977] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2017] [Revised: 04/05/2017] [Indexed: 11/06/2022] Open
Abstract
2-Alkylquinolone (2AQ) alkaloids are pharmaceutically and biologically important natural products produced by both bacteria and plants, with a wide range of biological effects, including antibacterial, cytotoxic, anticholinesterase, and quorum-sensing signaling activities. These diverse activities and 2AQ occurrence in vastly different phyla have raised much interest in the biosynthesis pathways leading to their production. Previous studies in plants have suggested that type III polyketide synthases (PKSs) might be involved in 2AQ biosynthesis, but this hypothesis is untested. To this end, we cloned two novel type III PKSs, alkyldiketide-CoA synthase (ADS) and alkylquinolone synthase (AQS), from the 2AQ-producing medicinal plant, Evodia rutaecarpa (Rutaceae). Functional analyses revealed that collaboration of ADS and AQS produces 2AQ via condensations of N-methylanthraniloyl-CoA, a fatty acyl-CoA, with malonyl-CoA. We show that ADS efficiently catalyzes the decarboxylative condensation of malonyl-CoA with a fatty acyl-CoA to produce an alkyldiketide-CoA, whereas AQS specifically catalyzes the decarboxylative condensation of an alkyldiketide acid with N-methylanthraniloyl-CoA to generate the 2AQ scaffold via C-C/C-N bond formations. Remarkably, the ADS and AQS crystal structures at 1.80 and 2.20 Å resolutions, respectively, indicated that the unique active-site architecture with Trp-332 and Cys-191 and the novel CoA-binding tunnel with Tyr-215 principally control the substrate and product specificities of ADS and AQS, respectively. These results provide additional insights into the catalytic versatility of the type III PKSs and their functional and evolutionary implications for 2AQ biosynthesis in plants and bacteria.
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Affiliation(s)
- Takashi Matsui
- From the Institute of Natural Medicine, University of Toyama, 2630-Sugitani, Toyama 930-0194
| | - Takeshi Kodama
- From the Institute of Natural Medicine, University of Toyama, 2630-Sugitani, Toyama 930-0194
| | - Takahiro Mori
- the Graduate School of Pharmaceutical Sciences, University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, and
| | - Tetsuhiro Tadakoshi
- From the Institute of Natural Medicine, University of Toyama, 2630-Sugitani, Toyama 930-0194
| | - Hiroshi Noguchi
- the School of Pharmaceutical Sciences, University of Shizuoka, 52-1 Yada, Suruga, Shizuoka 422-8526, Japan
| | - Ikuro Abe
- the Graduate School of Pharmaceutical Sciences, University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, and
| | - Hiroyuki Morita
- From the Institute of Natural Medicine, University of Toyama, 2630-Sugitani, Toyama 930-0194,
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46
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Strategies for inhibiting quorum sensing. Emerg Top Life Sci 2017; 1:23-30. [DOI: 10.1042/etls20160021] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2017] [Revised: 02/23/2017] [Accepted: 02/27/2017] [Indexed: 11/17/2022]
Abstract
The ability of bacterial cells to synchronize their behaviour through quorum sensing (QS) regulatory networks enables bacterial populations to mount co-operative responses against competing micro-organisms and host immune defences and to adapt to environmental challenges. Since QS controls the ability of many pathogenic bacteria to cause disease, it is an attractive target for novel antibacterial agents that control infection through inhibition of virulence and by rendering biofilms more susceptible to conventional antibiotics and host clearance pathways. QS systems provide multiple druggable molecular targets for inhibitors (QSIs) that include the enzymes involved in QS signal molecule biosynthesis and the receptors involved in signal transduction. Considerable advances in our understanding of the chemical biology of QS systems and their inhibition have been made, some promising QS targets structurally characterized, QSI screens devised and inhibitors identified. However, much more work is required before any QSI ‘hits’ with the appropriate pharmacological and pharmacokinetic properties can enter human clinical trials. Indeed, the relative efficacy of QSIs alone or as prophylactics or therapeutics or as adjuvants in combination with conventional antibiotics still needs to be extensively evaluated in vivo. Particular attention must be given to the measurement of successful QSI therapy outcomes with respect to bacterial clearance, immune response and pathophysiology. Currently, our understanding of the potential of QS as a promising antibacterial target suggests that it is likely to be of value with respect to a limited number of major pathogens.
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47
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Shanahan R, Reen FJ, Cano R, O'Gara F, McGlacken GP. The requirements at the C-3 position of alkylquinolones for signalling in Pseudomonas aeruginosa. Org Biomol Chem 2017; 15:306-310. [DOI: 10.1039/c6ob01930g] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
The ‘perfect storm’ of increasing bacterial antibiotic resistance and a decline in the discovery of new antibiotics, has made it necessary to search for new and innovative strategies to treat bacterial infections.
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Affiliation(s)
- Rachel Shanahan
- Department of Chemistry and Analytical & Biological Chemistry Research Facility (ABCRF)
- University College Cork
- Ireland
| | - F. Jerry Reen
- BIOMERIT Research Centre
- Department of Microbiology
- University College Cork
- Ireland
| | - Rafael Cano
- Department of Chemistry and Analytical & Biological Chemistry Research Facility (ABCRF)
- University College Cork
- Ireland
| | - Fergal O'Gara
- BIOMERIT Research Centre
- Department of Microbiology
- University College Cork
- Ireland
- School of Biomedical Sciences
| | - Gerard P. McGlacken
- Department of Chemistry and Analytical & Biological Chemistry Research Facility (ABCRF)
- University College Cork
- Ireland
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48
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Kamal AAM, Maurer CK, Allegretta G, Haupenthal J, Empting M, Hartmann RW. Quorum Sensing Inhibitors as Pathoblockers for Pseudomonas aeruginosa Infections: A New Concept in Anti-Infective Drug Discovery. TOPICS IN MEDICINAL CHEMISTRY 2017. [DOI: 10.1007/7355_2017_17] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
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49
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Prothiwa M, Szamosvári D, Glasmacher S, Böttcher T. Chemical probes for competitive profiling of the quorum sensing signal synthase PqsD of Pseudomonas aeruginosa. Beilstein J Org Chem 2016; 12:2784-2792. [PMID: 28144351 PMCID: PMC5238532 DOI: 10.3762/bjoc.12.277] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2016] [Accepted: 12/08/2016] [Indexed: 12/31/2022] Open
Abstract
The human pathogen Pseudomonas aeruginosa uses the pqs quorum sensing system to coordinate the production of its broad spectrum of virulence factors to facilitate colonization and infection of its host. Hereby, the enzyme PqsD is a virulence related quorum sensing signal synthase that catalyzes the central step in the biosynthesis of the Pseudomonas quinolone signals HHQ and PQS. We developed a library of cysteine reactive chemical probes with an alkyne handle for fluorescence tagging and report the selective and highly sensitive in vitro labelling of the active site cysteine of this important enzyme. Interestingly, only one type of probe, with a reactive α-chloroacetamide was capable of covalently reacting with the active site. We demonstrated the potential of our probes in a competitive labelling platform where we screened a library of synthetic HHQ and PQS analogues with heteroatom replacements and found several inhibitors of probe binding that may represent promising scaffolds for the development of customized PqsD inhibitors as well as a chemical toolbox to investigate the activity and active site specificity of the enzyme.
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Affiliation(s)
- Michaela Prothiwa
- Department of Chemistry, Konstanz Research School Chemical Biology, University of Konstanz, 78457 Konstanz, Germany
| | - Dávid Szamosvári
- Department of Chemistry, Konstanz Research School Chemical Biology, University of Konstanz, 78457 Konstanz, Germany
| | - Sandra Glasmacher
- Department of Chemistry, Konstanz Research School Chemical Biology, University of Konstanz, 78457 Konstanz, Germany
| | - Thomas Böttcher
- Department of Chemistry, Konstanz Research School Chemical Biology, University of Konstanz, 78457 Konstanz, Germany
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50
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Unravelling the Genome-Wide Contributions of Specific 2-Alkyl-4-Quinolones and PqsE to Quorum Sensing in Pseudomonas aeruginosa. PLoS Pathog 2016; 12:e1006029. [PMID: 27851827 PMCID: PMC5112799 DOI: 10.1371/journal.ppat.1006029] [Citation(s) in RCA: 101] [Impact Index Per Article: 12.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2016] [Accepted: 10/28/2016] [Indexed: 12/18/2022] Open
Abstract
The pqs quorum sensing (QS) system is crucial for Pseudomonas aeruginosa virulence both in vitro and in animal models of infection and is considered an ideal target for the development of anti-virulence agents. However, the precise role played by each individual component of this complex QS circuit in the control of virulence remains to be elucidated. Key components of the pqs QS system are 2-heptyl-4-hydroxyquinoline (HHQ), 2-heptyl-3-hydroxy-4-quinolone (PQS), 2-heptyl-4-hydroxyquinoline N-oxide (HQNO), the transcriptional regulator PqsR and the PQS-effector element PqsE. To define the individual contribution of each of these components to QS-mediated regulation, transcriptomic analyses were performed and validated on engineered P. aeruginosa strains in which the biosynthesis of 2-alkyl-4-quinolones (AQs) and expression of pqsE and pqsR have been uncoupled, facilitating the identification of the genes controlled by individual pqs system components. The results obtained demonstrate that i) the PQS biosynthetic precursor HHQ triggers a PqsR-dependent positive feedback loop that leads to the increased expression of only the pqsABCDE operon, ii) PqsE is involved in the regulation of diverse genes coding for key virulence determinants and biofilm development, iii) PQS promotes AQ biosynthesis, the expression of genes involved in the iron-starvation response and virulence factor production via PqsR-dependent and PqsR-independent pathways, and iv) HQNO does not influence transcription and hence does not function as a QS signal molecule. Overall this work has facilitated identification of the specific regulons controlled by individual pqs system components and uncovered the ability of PQS to contribute to gene regulation independent of both its ability to activate PqsR and to induce the iron-starvation response. Many bacterial pathogens control virulence gene expression and the development of antibiotic-resistant biofilms via intercellular communication through ‘quorum sensing’ (QS). QS systems depend on the synthesis, secretion and perception of diffusible signalling molecules that enable bacteria to synchronize their behaviour at the population level and are considered ideal targets for the development of anti-virulence drugs. Pseudomonas aeruginosa employs several overlapping QS circuits including the pqs system to control the expression of virulence determinants. The pqs QS system relies on multiple 2-alkyl-4-quinolones (AQs), including the Pseudomonas Quinolone Signal (PQS), as signal molecules. However, the individual contributions of key AQs and the effector proteins PqsR and PqsE within the auto-regulated pqs system have not been elucidated because of their inter-dependence. By constructing P. aeruginosa strains with multiple mutations in the pqs system and determining their transcriptomes in the presence or absence of PqsR, PqsE or exogenously supplied AQs, we define the distinct regulons involved and characterize a novel PQS signalling pathway independent of PqsR and the iron-starvation response.
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