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Cheng T, Cheang QW, Xu L, Sheng S, Li Z, Shi Y, Zhang H, Pang LM, Liu DX, Yang L, Liang ZX, Wang J. A PilZ domain protein interacts with the transcriptional regulator HinK to regulate type VI secretion system in Pseudomonas aeruginosa. J Biol Chem 2024; 300:105741. [PMID: 38340793 PMCID: PMC10912698 DOI: 10.1016/j.jbc.2024.105741] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2023] [Revised: 01/29/2024] [Accepted: 02/04/2024] [Indexed: 02/12/2024] Open
Abstract
Type VI secretion systems (T6SS) are bacterial macromolecular complexes that secrete effectors into target cells or the extracellular environment, leading to the demise of adjacent cells and providing a survival advantage. Although studies have shown that the T6SS in Pseudomonas aeruginosa is regulated by the Quorum Sensing system and second messenger c-di-GMP, the underlying molecular mechanism remains largely unknown. In this study, we discovered that the c-di-GMP-binding adaptor protein PA0012 has a repressive effect on the expression of the T6SS HSI-I genes in P. aeruginosa PAO1. To probe the mechanism by which PA0012 (renamed TssZ, Type Six Secretion System -associated PilZ protein) regulates the expression of HSI-I genes, we conducted yeast two-hybrid screening and identified HinK, a LasR-type transcriptional regulator, as the binding partner of TssZ. The protein-protein interaction between HinK and TssZ was confirmed through co-immunoprecipitation assays. Further analysis suggested that the HinK-TssZ interaction was weakened at high c-di-GMP concentrations, contrary to the current paradigm wherein c-di-GMP enhances the interaction between PilZ proteins and their partners. Electrophoretic mobility shift assays revealed that the non-c-di-GMP-binding mutant TssZR5A/R9A interacts directly with HinK and prevents it from binding to the promoter of the quorum-sensing regulator pqsR. The functional connection between TssZ and HinK is further supported by observations that TssZ and HinK impact the swarming motility, pyocyanin production, and T6SS-mediated bacterial killing activity of P. aeruginosa in a PqsR-dependent manner. Together, these results unveil a novel regulatory mechanism wherein TssZ functions as an inhibitor that interacts with HinK to control gene expression.
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Affiliation(s)
- Tianfang Cheng
- Integrative Microbiology Research Centre, Guangdong Province Key Laboratory of Microbial Signals and Disease Control, South China Agricultural University, Guangzhou, China
| | - Qing Wei Cheang
- School of Biological Sciences, Nanyang Technological University, Singapore, Singapore
| | - Linghui Xu
- Integrative Microbiology Research Centre, Guangdong Province Key Laboratory of Microbial Signals and Disease Control, South China Agricultural University, Guangzhou, China
| | - Shuo Sheng
- Integrative Microbiology Research Centre, Guangdong Province Key Laboratory of Microbial Signals and Disease Control, South China Agricultural University, Guangzhou, China; Key Laboratory of Basic Pharmacology of the Ministry of Education, Joint International Research Laboratory of Ethnomedicine of the Ministry of Education and Key Laboratory of Basic Pharmacology of Guizhou Province, Zunyi Medical University, Zunyi, Guizhou, China
| | - Zhaoting Li
- Integrative Microbiology Research Centre, Guangdong Province Key Laboratory of Microbial Signals and Disease Control, South China Agricultural University, Guangzhou, China
| | - Yu Shi
- Integrative Microbiology Research Centre, Guangdong Province Key Laboratory of Microbial Signals and Disease Control, South China Agricultural University, Guangzhou, China
| | - Huiyan Zhang
- Integrative Microbiology Research Centre, Guangdong Province Key Laboratory of Microbial Signals and Disease Control, South China Agricultural University, Guangzhou, China
| | - Li Mei Pang
- School of Biological Sciences, Nanyang Technological University, Singapore, Singapore
| | - Ding Xiang Liu
- Integrative Microbiology Research Centre, Guangdong Province Key Laboratory of Microbial Signals and Disease Control, South China Agricultural University, Guangzhou, China
| | - Liang Yang
- School of Biological Sciences, Nanyang Technological University, Singapore, Singapore
| | - Zhao-Xun Liang
- School of Biological Sciences, Nanyang Technological University, Singapore, Singapore.
| | - Junxia Wang
- Integrative Microbiology Research Centre, Guangdong Province Key Laboratory of Microbial Signals and Disease Control, South China Agricultural University, Guangzhou, China.
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Xiao H, Li J, Yang D, Du J, Li J, Lin S, Zhou H, Sun P, Xu J. Multidimensional Criteria for Virtual Screening of PqsR Inhibitors Based on Pharmacophore, Docking, and Molecular Dynamics. Int J Mol Sci 2024; 25:1869. [PMID: 38339148 PMCID: PMC10856439 DOI: 10.3390/ijms25031869] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2023] [Revised: 01/27/2024] [Accepted: 02/01/2024] [Indexed: 02/12/2024] Open
Abstract
Pseudomonas aeruginosa is a clinically challenging pathogen due to its high resistance to antibiotics. Quorum sensing inhibitors (QSIs) have been proposed as a promising strategy to overcome this resistance by interfering with the bacterial communication system. Among the potential targets of QSIs, PqsR is a key regulator of quorum sensing in Pseudomonas aeruginosa. However, the current research on PqsR inhibitors is limited by the lack of diversity in the chemical structures and the screening methods. Therefore, this study aims to develop a multidimensional screening model for PqsR inhibitors based on both ligand- and receptor-based approaches. First, a pharmacophore model was constructed from a training set of PqsR inhibitors to identify the essential features and spatial arrangement for the activity. Then, molecular docking and dynamics simulations were performed to explore the core interactions between PqsR inhibitors and their receptor. The results indicate that an effective PqsR inhibitor should possess two aromatic rings, one hydrogen bond acceptor, and two hydrophobic groups and should form strong interactions with the following four amino acid residues: TYR_258, ILE_236, LEU_208, and GLN_194. Moreover, the docking score and the binding free energy should be lower than -8 kcal/mol and -40 kcal/mol, respectively. Finally, the validity of the multidimensional screening model was confirmed by a test set of PqsR inhibitors, which showed a higher accuracy than the existing screening methods based on single characteristics. This multidimensional screening model would be a useful tool for the discovery and optimization of PqsR inhibitors in the future.
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Affiliation(s)
- Haichuan Xiao
- College of Pharmacy, Jinan University, Guangzhou 510632, China; (H.X.); (J.L.); (D.Y.); (J.D.); (J.L.); (S.L.); (H.Z.)
| | - Jiahao Li
- College of Pharmacy, Jinan University, Guangzhou 510632, China; (H.X.); (J.L.); (D.Y.); (J.D.); (J.L.); (S.L.); (H.Z.)
| | - Dongdong Yang
- College of Pharmacy, Jinan University, Guangzhou 510632, China; (H.X.); (J.L.); (D.Y.); (J.D.); (J.L.); (S.L.); (H.Z.)
| | - Jiarui Du
- College of Pharmacy, Jinan University, Guangzhou 510632, China; (H.X.); (J.L.); (D.Y.); (J.D.); (J.L.); (S.L.); (H.Z.)
| | - Jie Li
- College of Pharmacy, Jinan University, Guangzhou 510632, China; (H.X.); (J.L.); (D.Y.); (J.D.); (J.L.); (S.L.); (H.Z.)
| | - Shuqi Lin
- College of Pharmacy, Jinan University, Guangzhou 510632, China; (H.X.); (J.L.); (D.Y.); (J.D.); (J.L.); (S.L.); (H.Z.)
| | - Haibo Zhou
- College of Pharmacy, Jinan University, Guangzhou 510632, China; (H.X.); (J.L.); (D.Y.); (J.D.); (J.L.); (S.L.); (H.Z.)
- State Key Laboratory of Bioactive Molecules and Druggability Assessment, Jinan University, Guangzhou 510632, China
| | - Pinghua Sun
- College of Pharmacy, Jinan University, Guangzhou 510632, China; (H.X.); (J.L.); (D.Y.); (J.D.); (J.L.); (S.L.); (H.Z.)
- State Key Laboratory of Bioactive Molecules and Druggability Assessment, Jinan University, Guangzhou 510632, China
- Key Laboratory of Xinjiang Phytomedicine Resource and Utilization, Ministry of Education, School of Pharmacy, Shihezi University, Shihezi 832003, China
| | - Jun Xu
- College of Pharmacy, Jinan University, Guangzhou 510632, China; (H.X.); (J.L.); (D.Y.); (J.D.); (J.L.); (S.L.); (H.Z.)
- State Key Laboratory of Bioactive Molecules and Druggability Assessment, Jinan University, Guangzhou 510632, China
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Carullo G, Di Bonaventura G, Rossi S, Lupetti V, Tudino V, Brogi S, Butini S, Campiani G, Gemma S, Pompilio A. Development of Quinazolinone Derivatives as Modulators of Virulence Factors of Pseudomonas aeruginosa Cystic Fibrosis Strains. Molecules 2023; 28:6535. [PMID: 37764311 PMCID: PMC10536951 DOI: 10.3390/molecules28186535] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2023] [Revised: 09/04/2023] [Accepted: 09/07/2023] [Indexed: 09/29/2023] Open
Abstract
Pseudomonas aeruginosa (PA), one of the ESKAPE pathogens, is an opportunistic Gram-negative bacterium responsible for nosocomial infections in humans but also for infections in patients affected by AIDS, cancer, or cystic fibrosis (CF). Treatment of PA infections in CF patients is a global healthcare problem due to the ability of PA to gain antibiotic tolerance through biofilm formation. Anti-virulence compounds represent a promising approach as adjuvant therapy, which could reduce or eliminate the pathogenicity of PA without impacting its growth. Pyocyanin is one of the virulence factors whose production is modulated by the Pseudomonas quinolone signal (PQS) through its receptor PqsR. Different PqsR modulators have been synthesized over the years, highlighting this new powerful therapeutic strategy. Based on the promising structure of quinazolin-4(3H)-one, we developed compounds 7a-d, 8a,b, 9, 10, and 11a-f able to reduce biofilm formation and the production of virulence factors (pyocyanin and pyoverdine) at 50 µM in two PA strains responsible for CF acute and chronic infections. The developed compounds did not reduce the cell viability of IB3-1 bronchial CF cells, and computational studies confirmed the potential ability of novel compounds to act as potential Pqs system modulators.
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Affiliation(s)
- Gabriele Carullo
- Department of Biotechnology, Chemistry and Pharmacy, University of Siena, Via Aldo Moro 2, 53100 Siena, Italy; (G.C.); (S.R.); (V.T.); (S.B.); (G.C.)
| | - Giovanni Di Bonaventura
- Department of Medical, Oral and Biotechnological Sciences, School of Medicine and Health Sciences “G. d’Annunzio” University of Chieti-Pescara, Via dei Vestini 31, 66100 Chieti, Italy; (G.D.B.); (V.L.); (A.P.)
| | - Sara Rossi
- Department of Biotechnology, Chemistry and Pharmacy, University of Siena, Via Aldo Moro 2, 53100 Siena, Italy; (G.C.); (S.R.); (V.T.); (S.B.); (G.C.)
| | - Veronica Lupetti
- Department of Medical, Oral and Biotechnological Sciences, School of Medicine and Health Sciences “G. d’Annunzio” University of Chieti-Pescara, Via dei Vestini 31, 66100 Chieti, Italy; (G.D.B.); (V.L.); (A.P.)
| | - Valeria Tudino
- Department of Biotechnology, Chemistry and Pharmacy, University of Siena, Via Aldo Moro 2, 53100 Siena, Italy; (G.C.); (S.R.); (V.T.); (S.B.); (G.C.)
| | - Simone Brogi
- Department of Pharmacy, University of Pisa, Via Bonanno 6, 56126 Pisa, Italy;
| | - Stefania Butini
- Department of Biotechnology, Chemistry and Pharmacy, University of Siena, Via Aldo Moro 2, 53100 Siena, Italy; (G.C.); (S.R.); (V.T.); (S.B.); (G.C.)
| | - Giuseppe Campiani
- Department of Biotechnology, Chemistry and Pharmacy, University of Siena, Via Aldo Moro 2, 53100 Siena, Italy; (G.C.); (S.R.); (V.T.); (S.B.); (G.C.)
| | - Sandra Gemma
- Department of Biotechnology, Chemistry and Pharmacy, University of Siena, Via Aldo Moro 2, 53100 Siena, Italy; (G.C.); (S.R.); (V.T.); (S.B.); (G.C.)
| | - Arianna Pompilio
- Department of Medical, Oral and Biotechnological Sciences, School of Medicine and Health Sciences “G. d’Annunzio” University of Chieti-Pescara, Via dei Vestini 31, 66100 Chieti, Italy; (G.D.B.); (V.L.); (A.P.)
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Chakraborty A, Kabashi A, Wilk S, Rahme LG. Quorum-Sensing Signaling Molecule 2-Aminoacetophenone Mediates the Persistence of Pseudomonas aeruginosa in Macrophages by Interference with Autophagy through Epigenetic Regulation of Lipid Biosynthesis. mBio 2023; 14:e0015923. [PMID: 37010415 PMCID: PMC10127747 DOI: 10.1128/mbio.00159-23] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/04/2023] Open
Abstract
Macrophages are crucial components of the host's defense against pathogens. Recent studies indicate that macrophage functions are influenced by lipid metabolism. However, knowledge of how bacterial pathogens exploit macrophage lipid metabolism for their benefit remains rudimentary. We have shown that the Pseudomonas aeruginosa MvfR-regulated quorum-sensing (QS) signaling molecule 2-aminoacetophenone (2-AA) mediates epigenetic and metabolic changes associated with this pathogen's persistence in vivo. We provide evidence that 2-AA counteracts the ability of macrophages to clear the intracellular P. aeruginosa, leading to persistence. The intracellular action of 2-AA in macrophages is linked to reduced autophagic functions and the impaired expression of a central lipogenic gene, stearoyl-CoA desaturase 1 (Scd1), which catalyzes the biosynthesis of monounsaturated fatty acids. 2-AA also reduces the expression of the autophagic genes Unc-51-like autophagy activating kinase 1 (ULK1) and Beclin1 and the levels of the autophagosomal membrane protein microtubule-associated protein 1, light chain 3 isoform B (LC3B) and p62. Reduced autophagy is accompanied by the reduced expression of the lipogenic gene Scd1, preventing bacterial clearance. Adding the SCD1 substrates palmitoyl-CoA and stearoyl-CoA increases P. aeruginosa clearance by macrophages. The impact of 2-AA on lipogenic gene expression and autophagic machinery is histone deacetylase 1 (HDAC1) mediated, implicating the HDAC1 epigenetic marks at the promoter sites of Scd1 and Beclin1 genes. This work provides novel insights into the complex metabolic alterations and epigenetic regulation promoted by QS and uncovers additional 2-AA actions supporting P. aeruginosa sustainment in macrophages. These findings may aid in designing host-directed therapeutics and protective interventions against P. aeruginosa persistence. IMPORTANCE This work sheds new light on how P. aeruginosa limits bacterial clearance in macrophages through 2-aminoacetophenone (2-AA), a secreted signaling molecule by this pathogen that is regulated by the quorum-sensing transcription factor MvfR. The action of 2-AA on the lipid biosynthesis gene Scd1 and the autophagic genes ULK1 and Beclin1 appears to secure the reduced intracellular clearance of P. aeruginosa by macrophages. In support of the 2-AA effect on lipid biosynthesis, the ability of macrophages to reduce the intracellular P. aeruginosa burden is reinstated following the supplementation of palmitoyl-CoA and stearoyl-CoA. The 2-AA-mediated reduction of Scd1 and Beclin1 expression is linked to chromatin modifications, implicating the enzyme histone deacetylase 1 (HDAC1), thus opening new avenues for future strategies against this pathogen's persistence. Overall, the knowledge obtained from this work provides for developing new therapeutics against P. aeruginosa.
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Affiliation(s)
- Arijit Chakraborty
- Department of Surgery, Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts, USA
- Shriners Hospitals for Children Boston, Boston, Massachusetts, USA
| | - Asel Kabashi
- Department of Surgery, Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts, USA
| | - Samuel Wilk
- Department of Surgery, Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts, USA
| | - Laurence G Rahme
- Department of Surgery, Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts, USA
- Shriners Hospitals for Children Boston, Boston, Massachusetts, USA
- Department of Microbiology, Harvard Medical School, Boston, Massachusetts, USA
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Singh VK, Almpani M, Wheeler KM, Rahme LG. Interconnections of Pseudomonas aeruginosa Quorum-Sensing Systems in Intestinal Permeability and Inflammation. mBio 2023;:e0352422. [PMID: 36786582 DOI: 10.1128/mbio.03524-22] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/15/2023] Open
Abstract
Quorum sensing (QS) is a highly conserved microbial communication mechanism based on the production and sensing of secreted signaling molecules. The recalcitrant pathogen Pseudomonas aeruginosa is a problematic nosocomial pathogen with complex interconnected QS systems controlling multiple virulence functions. The relevance of QS in P. aeruginosa pathogenesis is well established; however, the regulatory interrelationships of the three major QS systems, LasR/LasI, MvfR (PqsR)/PqsABCD, and RhlR/RhlI, have been studied primarily in vitro. It is, therefore, unclear how these relationships translate to the host environment during infection. Here, we use a collection of P. aeruginosa QS mutants of the three major QS systems to assess the interconnections and contributions in intestinal inflammation and barrier function in vivo. This work reveals that MvfR, not LasR or RhlR, promotes intestinal inflammation during infection. In contrast, we find that P. aeruginosa-driven murine intestinal permeability is controlled by an interconnected QS network involving all three regulators, with MvfR situated upstream of LasR and RhlR. This study demonstrates the importance of understanding the interrelationships of the QS systems during infection and provides critical insights for developing successful antivirulence strategies. Moreover, this work provides a framework to interrogate QS systems in physiologically relevant settings. IMPORTANCE Pseudomonas aeruginosa is a common multidrug-resistant bacterial pathogen that seriously threatens critically ill and immunocompromised patients. Intestinal colonization by this pathogen is associated with elevated mortality rates. Disrupting bacterial communication is a desirable anti-infective approach since these systems coordinate multiple acute and chronic virulence functions in P. aeruginosa. Here, we investigate the role of each of the three major communication systems in the host intestinal functions. This work reveals that P. aeruginosa influences intestinal inflammation and permeability through distinct mechanisms.
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Shakour N, Taheri E, Rajabian F, Tarighi S, Soheili V, Hadizadeh F. Evaluating the Antivirulence Effects of New Thiazolidinedione Compounds Against Pseudomonas aeruginosa PAO1. Microb Drug Resist 2022; 28:1003-1018. [PMID: 36219761 DOI: 10.1089/mdr.2022.0134] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Pseudomonas aeruginosa is an opportunistic pathogen that causes several serious health problems and numerous forms of virulence. During the treatment of P. aeruginosa infections, the development of multidrug-resistant isolates creates significant clinical problems. Using antivirulence compounds to disrupt pathogenicity rather than killing the bacterium may be an interesting strategy to overcome this problem, because less harsh conditions will exist for the development of resistance. To reduce pathogenicity and biofilm formation, newly synthesized analogs of imidazolyl (8n) and previously synthesized analogs (8a-8m) with a similar backbone [the 5-(imidazolyl-methyl) thiazolidinediones] were tested against pyoverdine and pyocyanin production, protease activity, and biofilm formation. Compared to the positive control group, the best compounds reduced the production of pyoverdine (8n) by 89.57% and pyocyanin (8i) by 22.68%, and protease activity (8n) by 2.80% for PAO1 strain, at a concentration of 10 μM. Moreover, the biofilm formation assay showed a reduction of 87.94% (8i) for PAO1, as well as 30.53% (8d) and 44.65% (8m) for 1074 and 1707 strains, respectively. The compounds used in this study did not show any toxicity in the human dermal fibroblasts and 4T1 cells (viability higher than 90%). The in silico study of these compounds revealed that their antivirulence activity could be due to their interaction with the PqsR, PqsE, and LasR receptors.
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Affiliation(s)
- Neda Shakour
- Student Research Committee, Faculty of Medicine, Mashhad University of Medical Sciences, Mashhad, Iran.,Department of Medicinal Chemistry, School of Pharmacy, Mashhad University of Medical Sciences, Mashhad, Iran
| | - Elaheh Taheri
- Laboratory of Phytopathology, Department of Crop Protection, Ferdowsi University of Mashhad, Mashhad, Iran
| | - Fatemeh Rajabian
- Department of Pharmacodynamics and Toxicology, School of Pharmacy, Mashhad University of Medical Sciences, Mashhad, Iran
| | - Saeed Tarighi
- Laboratory of Phytopathology, Department of Crop Protection, Ferdowsi University of Mashhad, Mashhad, Iran
| | - Vahid Soheili
- Department of Pharmaceutical Control, School of Pharmacy, Mashhad University of Medical Sciences, Mashhad, Iran
| | - Farzin Hadizadeh
- Department of Medicinal Chemistry, School of Pharmacy, Mashhad University of Medical Sciences, Mashhad, Iran.,Biotechnology Research Center, Pharmaceutical Technology Institute, Mashhad University of Medical Sciences, Mashhad, Iran
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Montagut EJ, Raya J, Martin-Gomez MT, Vilaplana L, Rodriguez-Urretavizcaya B, Marco MP. An Immunochemical Approach to Detect the Quorum Sensing-Regulated Virulence Factor 2-Heptyl-4-Quinoline N-Oxide (HQNO) Produced by Pseudomonas aeruginosa Clinical Isolates. Microbiol Spectr 2022; 10:e0107321. [PMID: 35876587 PMCID: PMC9431570 DOI: 10.1128/spectrum.01073-21] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2021] [Accepted: 06/21/2022] [Indexed: 11/20/2022] Open
Abstract
Understanding quorum sensing (QS) and its role in the development of pathogenesis may provide new avenues for diagnosing, surveillance, and treatment of infectious diseases. For this purpose, the availability of reliable and efficient analytical diagnostic tools suitable to specifically detect and quantify these essential QS small molecules and QS regulated virulence factors is crucial. Here, we reported the development and evaluation of antibodies and an enzyme-linked immunosorbent assay (ELISA) for HQNO (2-heptyl-4-quinoline N-oxide), a QS product of the PqsR system, which has been found to act as a major virulence factor that interferes with the growth of other microorganisms. Despite the nonimmunogenic character of HQNO, the antibodies produced showed high avidity and the microplate-based ELISA developed could detect HQNO in the low nM range. Hence, a limit of detection (LOD) of 0.60 ± 0.13 nM had been reached in Müeller Hinton (MH) broth, which was below previously reported levels using sophisticated equipment based on liquid chromatography coupled to mass spectrometry. The HQNO profile of release of different Pseudomonas aeruginosa clinical isolates analyzed using this ELISA showed significant differences depending on whether the clinical isolates belonged to patients with acute or chronic infections. These data point to the possibility of using HQNO as a specific biomarker to diagnose P. aeruginosa infections and for patient surveillance. Considering the role of HQNO in inhibiting the growth of coinfecting bacteria, the present ELISA will allow the investigation of these complex bacterial interactions underlying infections. IMPORTANCE Bacteria use quorum sensing (QS) as a communication mechanism that releases small signaling molecules which allow synchronizing a series of activities involved in the pathogenesis, such as the biosynthesis of virulence factors or the regulation of growth of other bacterial species. HQNO is a metabolite of the Pseudomonas aeruginosa-specific QS signaling molecule PQS (Pseudomonas quinolone signal). In this work, the development of highly specific antibodies and an immunochemical diagnostic technology (ELISA) for the detection and quantification of HQNO was reported. The ELISA allowed profiling of the release of HQNO by clinical bacterial isolates, showing its potential value for diagnosing and surveillance of P. aeruginosa infections. Moreover, the antibodies and the ELISA reported here may contribute to the knowledge of other underlying conditions related to the pathology, such as the role of the interactions with other bacteria of a particular microbiota environment.
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Affiliation(s)
- Enrique J. Montagut
- Nanobiotechnology for Diagnostics (Nb4D), Department of Surfactants and Nanotechnology, Institute for Advanced Chemistry of Catalonia (IQAC) of the Spanish Council for Scientific Research (CSIC), Barcelona, Spain
- CIBER de Bioingeniería, Biomateriales, y Nanomedicina (CIBER-BBN), Barcelona, Spain
| | - Juan Raya
- Nanobiotechnology for Diagnostics (Nb4D), Department of Surfactants and Nanotechnology, Institute for Advanced Chemistry of Catalonia (IQAC) of the Spanish Council for Scientific Research (CSIC), Barcelona, Spain
- CIBER de Bioingeniería, Biomateriales, y Nanomedicina (CIBER-BBN), Barcelona, Spain
| | - M.-Teresa Martin-Gomez
- Microbiology Department, Vall d’Hebron University Hospital (VHUH), Barcelona, Spain
- Genetics and Microbiology Department, Universitat Autònoma de Barcelona (UAB), Barcelona, Spain
| | - Lluïsa Vilaplana
- Nanobiotechnology for Diagnostics (Nb4D), Department of Surfactants and Nanotechnology, Institute for Advanced Chemistry of Catalonia (IQAC) of the Spanish Council for Scientific Research (CSIC), Barcelona, Spain
- CIBER de Bioingeniería, Biomateriales, y Nanomedicina (CIBER-BBN), Barcelona, Spain
| | - Barbara Rodriguez-Urretavizcaya
- Nanobiotechnology for Diagnostics (Nb4D), Department of Surfactants and Nanotechnology, Institute for Advanced Chemistry of Catalonia (IQAC) of the Spanish Council for Scientific Research (CSIC), Barcelona, Spain
- CIBER de Bioingeniería, Biomateriales, y Nanomedicina (CIBER-BBN), Barcelona, Spain
| | - M.-Pilar Marco
- Nanobiotechnology for Diagnostics (Nb4D), Department of Surfactants and Nanotechnology, Institute for Advanced Chemistry of Catalonia (IQAC) of the Spanish Council for Scientific Research (CSIC), Barcelona, Spain
- CIBER de Bioingeniería, Biomateriales, y Nanomedicina (CIBER-BBN), Barcelona, Spain
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Boopathi S, Vashisth R, Mohanty AK, Jia AQ, Sivakumar N, Arockiaraj J. Bacillus subtilis BR4 derived stigmatellin Y interferes Pqs- PqsR mediated quorum sensing system of Pseudomonas aeruginosa. J Basic Microbiol 2022; 62:801-814. [PMID: 35355286 DOI: 10.1002/jobm.202200017] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2022] [Revised: 02/27/2022] [Accepted: 03/13/2022] [Indexed: 12/30/2022]
Abstract
Cell-to-cell communication is essentially required in bacteria for the production of multiple virulence factors and successful colonization in the host. Targeting the virulence factors production without hampering the growth of the pathogens is a potential strategy to control pathogenesis. To accomplish this, a total of 43 mangrove isolates were screened for quorum quenching (QQ) activity against Pseudomonas aeruginosa (PA), in which eight bacteria have shown antibiofilm activity without hampering the growth of the PA. Prominent QQ activity was observed in Bacillus subtilis BR4. Previously, we found that BR4 produces stigmatellin Y, a structural analogue of PQS signal of PA, which could competitively bind with PqsR receptor and inhibits the quorum sensing (QS) system of PA. Further, stigmatellin Y containing ethyl acetate extract (S-EAE) (100 µg ml-1 ) of BR4 significantly inhibits (p < 0.001) the biofilm formation of PA. Confocal laser scanning microscope (CLSM) and scanning electron microscope (SEM) analysis also fortified the QQ activity of BR4. Furthermore, S-EAE of BR4 (500 µg ml-1 ) has significantly reduced the production of virulence factors, including protease, elastase, pyocyanin and extracellular polysaccharides substances. Furthermore, liquid chromatography-mass spectrometry (LC-MS)/MS analysis affirms that BR4 intercepts the PQS-mediated QS system by reducing the synthesis of as many PQS signals, including precursor molecule (243.162313 Da) of PQS signal. Thus, S-EAE of B. subtilis BR4 could be used as a promising therapeutic agent to combat QS system-mediated pathogenesis of PA. Further therapeutic potentials of stigmatellin Y to be evaluated in clinical studies for the treatment of multidrug resistant PA.
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Affiliation(s)
- Seenivasan Boopathi
- Department of Biotechnology, College of Science and Humanities, SRM Institute of Science and Technology, Kattankulathur, Chennai, Tamil Nadu, India
| | | | - Ashok Kumar Mohanty
- Cell Biology and Proteomics Lab, Animal Biotechnology Centre, National Dairy Research Institute, Karnal, Haryana, India
| | - Ai-Qun Jia
- School of Pharmaceutical Sciences, Key Laboratory of Tropical Biological Resources of Ministry Education, State Key Laboratory of Marine Resource Utilization in South China Sea, Hainan University, Haikou, China
| | - Natesan Sivakumar
- Department of Molecular Microbiology, School of Biotechnology, Madurai Kamaraj University, Madurai, Tamil Nadu, India
| | - Jesu Arockiaraj
- Department of Biotechnology, College of Science and Humanities, SRM Institute of Science and Technology, Kattankulathur, Chennai, Tamil Nadu, India
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9
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Trognon J, Vera G, Rima M, Stigliani JL, Amielet L, El Hage S, Lajoie B, Roques C, El Garah F. Investigation of Direct and Retro Chromone-2-Carboxamides Based Analogs of Pseudomonas aeruginosa Quorum Sensing Signal as New Anti-Biofilm Agents. Pharmaceuticals (Basel) 2022; 15. [PMID: 35455414 DOI: 10.3390/ph15040417] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2022] [Revised: 03/19/2022] [Accepted: 03/28/2022] [Indexed: 11/17/2022] Open
Abstract
Biofilm formation is considered a major cause of therapeutic failure because bacteria in biofilms have higher protection against antimicrobials. Thus, biofilm-related infections are extremely challenging to treat and pose major concerns for public health, along with huge economic impacts. Pseudomonas aeruginosa, in particular, is a “critical priority” pathogen, responsible for severe infections, especially in cystic fibrosis patients because of its capacity to form resistant biofilms. Therefore, new therapeutic approaches are needed to complete the pipeline of molecules offering new targets and modes of action. Biofilm formation is mainly controlled by Quorum Sensing (QS), a communication system based on signaling molecules. In the present study, we employed a molecular docking approach (Autodock Vina) to assess two series of chromones-based compounds as possible ligands for PqsR, a LuxR-type receptor. Most compounds showed good predicted affinities for PqsR, higher than the PQS native ligand. Encouraged by these docking results, we synthesized a library of 34 direct and 25 retro chromone carboxamides using two optimized routes from 2-chromone carboxylic acid as starting material for both series. We evaluated the synthesized carboxamides for their ability to inhibit the biofilm formation of P. aeruginosa in vitro. Overall, results showed several chromone 2-carboxamides of the retro series are potent inhibitors of the formation of P. aeruginosa biofilms (16/25 compound with % inhibition ≥ 50% at 50 μM), without cytotoxicity on Vero cells (IC50 > 1.0 mM). The 2,4-dinitro-N-(4-oxo-4H-chromen-2-yl) benzamide (6n) was the most promising antibiofilm compound, with potential for hit to lead optimization.
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10
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Murray EJ, Dubern JF, Chan WC, Chhabra SR, Williams P. A Pseudomonas aeruginosa PQS quorum-sensing system inhibitor with anti-staphylococcal activity sensitizes polymicrobial biofilms to tobramycin. Cell Chem Biol 2022; 29:1187-1199.e6. [PMID: 35259345 PMCID: PMC9605878 DOI: 10.1016/j.chembiol.2022.02.007] [Citation(s) in RCA: 18] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2020] [Revised: 07/16/2021] [Accepted: 02/15/2022] [Indexed: 12/23/2022]
Abstract
As single- and mixed-species biofilms, Staphylococcus aureus and Pseudomonas aeruginosa cause difficult-to-eradicate chronic infections. In P. aeruginosa, pseudomonas quinolone (PQS)-dependent quorum sensing regulates virulence and biofilm development that can be attenuated via antagonists targeting the transcriptional regulator PqsR (MvfR). Here, we exploited a quinazolinone (QZN) library including PqsR agonists and antagonists for their activity against S. aureus alone, when co-cultured with P. aeruginosa, and in combination with the aminoglycoside tobramycin. The PqsR inhibitor, QZN 34 killed planktonic Gram-positives but not Gram-negatives. QZN 34 prevented S. aureus biofilm formation, severely damaged established S. aureus biofilms, and perturbed P. aeruginosa biofilm development. Although P. aeruginosa protected S. aureus from tobramycin in mixed biofilms, the combination of aminoglycoside antibiotic with QZN 34 eradicated the mixed-species biofilm. The mechanism of action of QZN 34 toward Gram-positive bacteria is shown to involve membrane perturbation and dissipation of transmembrane potential. QZNs inhibit PQS-dependent quorum sensing and reduce biofilm formation in Pseudomonas aeruginosa A subset of QZNs is bactericidal for planktonic Staphylococcus aureus and severely damages biofilms In mixed species biofilms, P. aeruginosa protects S. aureus from tobramycin Tobramycin plus QZN eradicates mixed P. aeruginosa and S. aureus biofilms
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Affiliation(s)
- Ewan J Murray
- National Biofilms Innovation Centre, Biodiscovery Institute and School of Life Sciences, University of Nottingham, University Park, Nottingham NG7 2RD, UK
| | - Jean-Frédéric Dubern
- National Biofilms Innovation Centre, Biodiscovery Institute and School of Life Sciences, University of Nottingham, University Park, Nottingham NG7 2RD, UK
| | - Weng C Chan
- School of Pharmacy, Biodiscovery Institute, University of Nottingham, University Park, Nottingham NG7 2RD, UK
| | - Siri Ram Chhabra
- National Biofilms Innovation Centre, Biodiscovery Institute and School of Life Sciences, University of Nottingham, University Park, Nottingham NG7 2RD, UK
| | - Paul Williams
- National Biofilms Innovation Centre, Biodiscovery Institute and School of Life Sciences, University of Nottingham, University Park, Nottingham NG7 2RD, UK.
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11
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Miranda SW, Asfahl KL, Dandekar AA, Greenberg EP. Pseudomonas aeruginosa Quorum Sensing. Adv Exp Med Biol 2022; 1386:95-115. [PMID: 36258070 PMCID: PMC9942581 DOI: 10.1007/978-3-031-08491-1_4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/23/2023]
Abstract
Pseudomonas aeruginosa, like many bacteria, uses chemical signals to communicate between cells in a process called quorum sensing (QS). QS allows groups of bacteria to sense population density and, in response to changing cell densities, to coordinate behaviors. The P. aeruginosa QS system consists of two complete circuits that involve acyl-homoserine lactone signals and a third system that uses quinolone signals. Together, these three QS circuits regulate the expression of hundreds of genes, many of which code for virulence factors. P. aeruginosa has become a model for studying the molecular biology of QS and the ecology and evolution of group behaviors in bacteria. In this chapter, we recount the history of discovery of QS systems in P. aeruginosa, discuss how QS relates to virulence and the ecology of this bacterium, and explore strategies to inhibit QS. Finally, we discuss future directions for research in P. aeruginosa QS.
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Affiliation(s)
| | - Kyle L Asfahl
- Department of Microbiology, University of Washington School of Medicine, Seattle, WA, USA
| | - Ajai A Dandekar
- Department of Microbiology, University of Washington School of Medicine, Seattle, WA, USA
- Department of Medicine, University of Washington School of Medicine, Seattle, WA, USA
| | - E P Greenberg
- Department of Microbiology, University of Washington School of Medicine, Seattle, WA, USA.
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12
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Soukarieh F, Mashabi A, Richardson W, Oton EV, Romero M, Roberston SN, Grossman S, Sou T, Liu R, Halliday N, Kukavica-Ibrulj I, Levesque RC, Bergstrom CAS, Kellam B, Emsley J, Heeb S, Williams P, Stocks MJ, Cámara M. Design and Evaluation of New Quinazolin-4(3 H)-one Derived PqsR Antagonists as Quorum Sensing Quenchers in Pseudomonas aeruginosa. ACS Infect Dis 2021; 7:2666-2685. [PMID: 34503335 DOI: 10.1021/acsinfecdis.1c00175] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
P. aeruginosa (PA) continues to pose a threat to global public health due to its high levels of antimicrobial resistance (AMR). The ongoing AMR crisis has led to an alarming shortage of effective treatments for resistant microbes, and hence there is a pressing demand for the development of novel antimicrobial interventions. The potential use of antivirulence therapeutics to tackle bacterial infections has attracted considerable attention over the past decades as they hamper the pathogenicity of target microbes with reduced selective pressure, minimizing the emergence of resistance. One such approach is to interfere with the PA pqs quorum sensing system which upon the interaction of PqsR, a Lys-R type transcriptional regulator, with its cognate signal molecules 4-hydroxy-2-heptylquinoline (HHQ) and 2-heptyl-3-hydroxy-4-quinolone (PQS), governs multiple virulence traits and host-microbe interactions. In this study, we report the hit identification and optimization of PqsR antagonists using virtual screening coupled with whole cell assay validation. The optimized hit compound 61 ((R)-2-(4-(3-(6-chloro-4-oxoquinazolin-3(4H)-yl)-2-hydroxypropoxy)phenyl)acetonitrile) was found to inhibit the expression of the PA PpqsA promoter controlled by PqsR with an IC50 of 1 μM. Using isothermal titration calorimetry, a Kd of 10 nM for the PqsR ligand binding domain (PqsRLBD) was determined for 61. Furthermore, the crystal structure of 61 with PqsRLBD was attained with a resolution of 2.65 Å. Compound 61 significantly reduced levels of pyocyanin, PQS, and HHQ in PAO1-L, PA14 lab strains and PAK6085 clinical isolate. Furthermore, this compound potentiated the effect of ciprofloxacin in early stages of biofilm treatment and in Galleria mellonella infected with PA. Altogether, this data shows 61 as a potent PqsR inhibitor with potential for hit to lead optimization toward the identification of a PA QS inhibitor which can be advanced into preclinical development.
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Affiliation(s)
- Fadi Soukarieh
- School of Life Sciences, University of Nottingham Biodiscovery Institute, University of Nottingham, Nottingham, NG7 2RD, U.K
- The National Biofilms Innovation Centre, University of Nottingham Biodiscovery Institute, University of Nottingham, Nottingham, NG7 2RD, U.K
| | - Alaa Mashabi
- School of Pharmacy, University of Nottingham Biodiscovery Institute, University of Nottingham, Nottingham, NG7 2RD, U.K
| | - William Richardson
- School of Pharmacy, University of Nottingham Biodiscovery Institute, University of Nottingham, Nottingham, NG7 2RD, U.K
| | - Eduard Vico Oton
- School of Life Sciences, University of Nottingham Biodiscovery Institute, University of Nottingham, Nottingham, NG7 2RD, U.K
| | - Manuel Romero
- School of Life Sciences, University of Nottingham Biodiscovery Institute, University of Nottingham, Nottingham, NG7 2RD, U.K
- The National Biofilms Innovation Centre, University of Nottingham Biodiscovery Institute, University of Nottingham, Nottingham, NG7 2RD, U.K
| | - Shaun N. Roberston
- School of Life Sciences, University of Nottingham Biodiscovery Institute, University of Nottingham, Nottingham, NG7 2RD, U.K
- The National Biofilms Innovation Centre, University of Nottingham Biodiscovery Institute, University of Nottingham, Nottingham, NG7 2RD, U.K
| | - Scott Grossman
- School of Pharmacy, University of Nottingham Biodiscovery Institute, University of Nottingham, Nottingham, NG7 2RD, U.K
| | - Tomas Sou
- Department of Pharmacy, Uppsala University, Uppsala SE-751 23, Sweden
| | - Ruiling Liu
- School of Pharmacy, University of Nottingham Biodiscovery Institute, University of Nottingham, Nottingham, NG7 2RD, U.K
| | - Nigel Halliday
- School of Life Sciences, University of Nottingham Biodiscovery Institute, University of Nottingham, Nottingham, NG7 2RD, U.K
| | - Irena Kukavica-Ibrulj
- Institut de Biologie Integrative et des Systemes, Universite Laval, Quebec G1 V 0A6, Canada
| | - Roger C. Levesque
- Institut de Biologie Integrative et des Systemes, Universite Laval, Quebec G1 V 0A6, Canada
| | | | - Barrie Kellam
- School of Pharmacy, University of Nottingham Biodiscovery Institute, University of Nottingham, Nottingham, NG7 2RD, U.K
| | - Jonas Emsley
- School of Pharmacy, University of Nottingham Biodiscovery Institute, University of Nottingham, Nottingham, NG7 2RD, U.K
- The National Biofilms Innovation Centre, University of Nottingham Biodiscovery Institute, University of Nottingham, Nottingham, NG7 2RD, U.K
| | - Stephan Heeb
- School of Life Sciences, University of Nottingham Biodiscovery Institute, University of Nottingham, Nottingham, NG7 2RD, U.K
| | - Paul Williams
- School of Life Sciences, University of Nottingham Biodiscovery Institute, University of Nottingham, Nottingham, NG7 2RD, U.K
- The National Biofilms Innovation Centre, University of Nottingham Biodiscovery Institute, University of Nottingham, Nottingham, NG7 2RD, U.K
| | - Michael J. Stocks
- School of Pharmacy, University of Nottingham Biodiscovery Institute, University of Nottingham, Nottingham, NG7 2RD, U.K
- The National Biofilms Innovation Centre, University of Nottingham Biodiscovery Institute, University of Nottingham, Nottingham, NG7 2RD, U.K
| | - Miguel Cámara
- School of Life Sciences, University of Nottingham Biodiscovery Institute, University of Nottingham, Nottingham, NG7 2RD, U.K
- The National Biofilms Innovation Centre, University of Nottingham Biodiscovery Institute, University of Nottingham, Nottingham, NG7 2RD, U.K
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13
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Jafari P, Luscher A, Siriwardena T, Michetti M, Que YA, Rahme LG, Reymond JL, Raffoul W, Van Delden C, Applegate LA, Köhler T. Antimicrobial Peptide Dendrimers and Quorum-Sensing Inhibitors in Formulating Next-Generation Anti-Infection Cell Therapy Dressings for Burns. Molecules 2021; 26:molecules26133839. [PMID: 34202446 PMCID: PMC8270311 DOI: 10.3390/molecules26133839] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2021] [Revised: 06/02/2021] [Accepted: 06/12/2021] [Indexed: 12/21/2022] Open
Abstract
Multidrug resistance infections are the main cause of failure in the pro-regenerative cell-mediated therapy of burn wounds. The collagen-based matrices for delivery of cells could be potential substrates to support bacterial growth and subsequent lysis of the collagen leading to a cell therapy loss. In this article, we report the development of a new generation of cell therapy formulations with the capacity to resist infections through the bactericidal effect of antimicrobial peptide dendrimers and the anti-virulence effect of anti-quorum sensing MvfR (PqsR) system compounds, which are incorporated into their formulation. Anti-quorum sensing compounds limit the pathogenicity and antibiotic tolerance of pathogenic bacteria involved in the burn wound infections, by inhibiting their virulence pathways. For the first time, we report a biological cell therapy dressing incorporating live progenitor cells, antimicrobial peptide dendrimers, and anti-MvfR compounds, which exhibit bactericidal and anti-virulence properties without compromising the viability of the progenitor cells.
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Affiliation(s)
- Paris Jafari
- Regenerative Therapy Unit (UTR), Department of Musculoskeletal Medicine DAL, Lausanne University Hospital, 1011 Lausanne, Switzerland; (P.J.); (M.M.)
- Service of Plastic, Reconstructive & Hand Surgery, Lausanne University Hospital, 1011 Lausanne, Switzerland;
- Department of Pharmaceutics and Pharmaceutical Chemistry, College of Pharmacy, University of Utah, Salt Lake City, UT 84112, USA
| | - Alexandre Luscher
- Department of Microbiology and Molecular Medicine, University of Geneva, 1211 Geneva, Switzerland; (A.L.); (C.V.D.)
| | - Thissa Siriwardena
- Department of Chemistry, Biochemistry and Pharmaceutical Sciences, University of Bern, 3012 Bern, Switzerland; (T.S.); (J.-L.R.)
| | - Murielle Michetti
- Regenerative Therapy Unit (UTR), Department of Musculoskeletal Medicine DAL, Lausanne University Hospital, 1011 Lausanne, Switzerland; (P.J.); (M.M.)
- Service of Plastic, Reconstructive & Hand Surgery, Lausanne University Hospital, 1011 Lausanne, Switzerland;
| | - Yok-Ai Que
- Department of Intensive Care Medicine, Inselspital, Bern University Hospital, University of Bern, 3010 Bern, Switzerland;
| | - Laurence G. Rahme
- Department of Surgery, Harvard Medical School and Massachusetts General Hospital, Boston, MA 02114, USA;
- Shriners Hospitals for Children Boston, Boston, MA 02114, USA
- Department of Microbiology and Immunobiology, Harvard Medical School, Boston, MA 02115, USA
| | - Jean-Louis Reymond
- Department of Chemistry, Biochemistry and Pharmaceutical Sciences, University of Bern, 3012 Bern, Switzerland; (T.S.); (J.-L.R.)
| | - Wassim Raffoul
- Service of Plastic, Reconstructive & Hand Surgery, Lausanne University Hospital, 1011 Lausanne, Switzerland;
| | - Christian Van Delden
- Department of Microbiology and Molecular Medicine, University of Geneva, 1211 Geneva, Switzerland; (A.L.); (C.V.D.)
- Division on Infectious Disease and Transplantation, University Hospital of Geneva, 1205 Geneva, Switzerland
| | - Lee Ann Applegate
- Regenerative Therapy Unit (UTR), Department of Musculoskeletal Medicine DAL, Lausanne University Hospital, 1011 Lausanne, Switzerland; (P.J.); (M.M.)
- Service of Plastic, Reconstructive & Hand Surgery, Lausanne University Hospital, 1011 Lausanne, Switzerland;
- Center for Applied Biotechnology and Molecular Medicine, University of Zurich, Winterthurerstrasse 260, 8057 Zurich, Switzerland
- Oxford OSCAR Suzhou Center, Oxford University, Suzhou 215028, China
- Correspondence: (L.A.A.); (T.K.); Tel.: +41-21-314-3510 (L.A.A.); +41-22-379-5571 (T.K.)
| | - Thilo Köhler
- Department of Microbiology and Molecular Medicine, University of Geneva, 1211 Geneva, Switzerland; (A.L.); (C.V.D.)
- Division on Infectious Disease and Transplantation, University Hospital of Geneva, 1205 Geneva, Switzerland
- Correspondence: (L.A.A.); (T.K.); Tel.: +41-21-314-3510 (L.A.A.); +41-22-379-5571 (T.K.)
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14
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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] [What about the content of this article? (0)] [Affiliation(s)] [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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15
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Soukarieh F, Liu R, Romero M, Roberston SN, Richardson W, Lucanto S, Oton EV, Qudus NR, Mashabi A, Grossman S, Ali S, Sou T, Kukavica-Ibrulj I, Levesque RC, Bergström CAS, Halliday N, Mistry SN, Emsley J, Heeb S, Williams P, Cámara M, Stocks MJ. Hit Identification of New Potent PqsR Antagonists as Inhibitors of Quorum Sensing in Planktonic and Biofilm Grown Pseudomonas aeruginosa. Front Chem 2020; 8:204. [PMID: 32432073 PMCID: PMC7213079 DOI: 10.3389/fchem.2020.00204] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2019] [Accepted: 03/04/2020] [Indexed: 12/11/2022] Open
Abstract
Current treatments for Pseudomonas aeruginosa infections are becoming less effective because of the increasing rates of multi-antibiotic resistance. Pharmacological targeting of virulence through inhibition of quorum sensing (QS) dependent virulence gene regulation has considerable therapeutic potential. In P. aeruginosa, the pqs QS system regulates the production of multiple virulence factors as well as biofilm maturation and is a promising approach for developing antimicrobial adjuvants for combatting drug resistance. In this work, we report the hit optimisation for a series of potent novel inhibitors of PqsR, a key regulator of the pqs system, bearing a 2-((5-methyl-5H-[1,2,4]triazino[5,6-b]indol-3-yl)thio) acetamide scaffold. The initial hit compound 7 (PAO1-L IC50 0.98 ± 0.02 μM, PA14 inactive at 10 μM) was obtained through a virtual screening campaign performed on the PqsR ligand binding domain using the University of Nottingham Managed Chemical Compound Collection. Hit optimisation gave compounds with enhanced potency against strains PAO1-L and PA14, evaluated using P. aeruginosa pqs-based QS bioreporter assays. Compound 40 (PAO1-L IC50 0.25 ± 0.12 μM, PA14 IC50 0.34 ± 0.03 μM) is one of the most potent PqsR antagonists reported showing significant inhibition of P. aeruginosa pyocyanin production and pqs system signaling in both planktonic cultures and biofilms. The co-crystal structure of 40 with the PqsR ligand binding domain revealed the specific binding interactions occurring between inhibitor and this key regulatory protein.
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Affiliation(s)
- Fadi Soukarieh
- School of Life Sciences, University of Nottingham Biodiscovery Institute, University of Nottingham, Nottingham, United Kingdom.,The National Biofilms Innovation Centre, University of Nottingham, Nottingham, United Kingdom
| | - Ruiling Liu
- School of Pharmacy, University of Nottingham Biodiscovery Institute, University of Nottingham, Nottingham, United Kingdom
| | - Manuel Romero
- School of Life Sciences, University of Nottingham Biodiscovery Institute, University of Nottingham, Nottingham, United Kingdom.,The National Biofilms Innovation Centre, University of Nottingham, Nottingham, United Kingdom
| | - Shaun N Roberston
- School of Life Sciences, University of Nottingham Biodiscovery Institute, University of Nottingham, Nottingham, United Kingdom.,The National Biofilms Innovation Centre, University of Nottingham, Nottingham, United Kingdom
| | - William Richardson
- School of Pharmacy, University of Nottingham Biodiscovery Institute, University of Nottingham, Nottingham, United Kingdom
| | - Simone Lucanto
- School of Life Sciences, University of Nottingham Biodiscovery Institute, University of Nottingham, Nottingham, United Kingdom.,The National Biofilms Innovation Centre, University of Nottingham, Nottingham, United Kingdom
| | - Eduard Vico Oton
- School of Life Sciences, University of Nottingham Biodiscovery Institute, University of Nottingham, Nottingham, United Kingdom
| | - Naim Ruhul Qudus
- School of Life Sciences, University of Nottingham Biodiscovery Institute, University of Nottingham, Nottingham, United Kingdom
| | - Alaa Mashabi
- School of Pharmacy, University of Nottingham Biodiscovery Institute, University of Nottingham, Nottingham, United Kingdom
| | - Scott Grossman
- School of Pharmacy, University of Nottingham Biodiscovery Institute, University of Nottingham, Nottingham, United Kingdom
| | - Sadiqur Ali
- School of Life Sciences, University of Nottingham Biodiscovery Institute, University of Nottingham, Nottingham, United Kingdom
| | - Tomás Sou
- Drug Delivery Group, Department of Pharmacy, Uppsala University, Uppsala, Sweden.,Pharmacometrics Group, Department of Pharmaceutical Biosciences, Uppsala University, Uppsala, Sweden
| | - Irena Kukavica-Ibrulj
- Institut de Biologie Intégrative et des Systèmes, Université Laval, Quebec City, QC, Canada
| | - Roger C Levesque
- Institut de Biologie Intégrative et des Systèmes, Université Laval, Quebec City, QC, Canada
| | - Christel A S Bergström
- Drug Delivery Group, Department of Pharmacy, Uppsala University, Uppsala, Sweden.,The Swedish Drug Delivery Center, Department of Pharmacy, Uppsala University, Uppsala, Sweden
| | - Nigel Halliday
- School of Life Sciences, University of Nottingham Biodiscovery Institute, University of Nottingham, Nottingham, United Kingdom
| | - Shailesh N Mistry
- School of Pharmacy, University of Nottingham Biodiscovery Institute, University of Nottingham, Nottingham, United Kingdom
| | - Jonas Emsley
- The National Biofilms Innovation Centre, University of Nottingham, Nottingham, United Kingdom.,School of Pharmacy, University of Nottingham Biodiscovery Institute, University of Nottingham, Nottingham, United Kingdom
| | - Stephan Heeb
- School of Life Sciences, University of Nottingham Biodiscovery Institute, University of Nottingham, Nottingham, United Kingdom
| | - Paul Williams
- School of Life Sciences, University of Nottingham Biodiscovery Institute, University of Nottingham, Nottingham, United Kingdom.,The National Biofilms Innovation Centre, University of Nottingham, Nottingham, United Kingdom
| | - Miguel Cámara
- School of Life Sciences, University of Nottingham Biodiscovery Institute, University of Nottingham, Nottingham, United Kingdom.,The National Biofilms Innovation Centre, University of Nottingham, Nottingham, United Kingdom
| | - Michael J Stocks
- The National Biofilms Innovation Centre, University of Nottingham, Nottingham, United Kingdom.,School of Pharmacy, University of Nottingham Biodiscovery Institute, University of Nottingham, Nottingham, United Kingdom
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16
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Mellini M, Di Muzio E, D’Angelo F, Baldelli V, Ferrillo S, Visca P, Leoni L, Polticelli F, Rampioni G. In silico Selection and Experimental Validation of FDA-Approved Drugs as Anti-quorum Sensing Agents. Front Microbiol 2019; 10:2355. [PMID: 31649658 PMCID: PMC6796623 DOI: 10.3389/fmicb.2019.02355] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2019] [Accepted: 09/27/2019] [Indexed: 12/13/2022] Open
Abstract
The emergence of antibiotic resistant bacterial pathogens is increasing at an unprecedented pace, calling for the development of new therapeutic options. Small molecules interfering with virulence processes rather than growth hold promise as an alternative to conventional antibiotics. Anti-virulence agents are expected to decrease bacterial virulence and to pose reduced selective pressure for the emergence of resistance. In the opportunistic pathogen Pseudomonas aeruginosa the expression of key virulence traits is controlled by quorum sensing (QS), an intercellular communication process that coordinates gene expression at the population level. Hence, QS inhibitors represent promising anti-virulence agents against P. aeruginosa. Virtual screenings allow fast and cost-effective selection of target ligands among vast libraries of molecules, thus accelerating the time and limiting the cost of conventional drug-discovery processes, while the drug-repurposing approach is based on the identification of off-target activity of FDA-approved drugs, likely endowed with low cytotoxicity and favorable pharmacological properties. This study aims at combining the advantages of virtual screening and drug-repurposing approaches to identify new QS inhibitors targeting the pqs QS system of P. aeruginosa. An in silico library of 1,467 FDA-approved drugs has been screened by molecular docking, and 5 hits showing the highest predicted binding affinity for the pqs QS receptor PqsR (also known as MvfR) have been selected. In vitro experiments have been performed by engineering ad hoc biosensor strains, which were used to verify the ability of hit compounds to decrease PqsR activity in P. aeruginosa. Phenotypic analyses confirmed the impact of the most promising hit, the antipsychotic drug pimozide, on the expression of P. aeruginosa PqsR-controlled virulence traits. Overall, this study highlights the potential of virtual screening campaigns of FDA-approved drugs to rapidly select new inhibitors of important bacterial functions.
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Affiliation(s)
- Marta Mellini
- Department of Science, University Roma Tre, Rome, Italy
| | | | | | | | | | - Paolo Visca
- Department of Science, University Roma Tre, Rome, Italy
| | - Livia Leoni
- Department of Science, University Roma Tre, Rome, Italy
| | - Fabio Polticelli
- Department of Science, University Roma Tre, Rome, Italy
- National Institute of Nuclear Physics, Roma Tre Section, Rome, Italy
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Soheili V, Tajani AS, Ghodsi R, Bazzaz BSF. 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] [What about the content of this article? (0)] [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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Soukarieh F, Vico Oton E, Dubern JF, Gomes J, Halliday N, de Pilar Crespo M, Ramírez-Prada J, Insuasty B, Abonia R, Quiroga J, Heeb S, Williams P, Stocks MJ, Cámara M. In Silico and in Vitro-Guided Identification of Inhibitors of Alkylquinolone-Dependent Quorum Sensing in Pseudomonas aeruginosa. Molecules 2018; 23:E257. [PMID: 29382099 PMCID: PMC6017655 DOI: 10.3390/molecules23020257] [Citation(s) in RCA: 37] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2017] [Revised: 01/20/2018] [Accepted: 01/20/2018] [Indexed: 01/21/2023] Open
Abstract
Pseudomonas aeruginosa is a major opportunistic pathogen in cystic fibrosis, wound and nosocomial infections, posing a serious burden to public health, due to its antibiotic resistance. The P. aeruginosa Pseudomonas Quinolone System (pqs) quorum sensing system, driven by the activation of the transcriptional regulator, PqsR (MvfR) by alkylquinolone (AQ) signal molecules, is a key player in the regulation of virulence and a potential target for the development of novel antibacterial agents. In this study, we performed in silico docking analysis, coupled with screening using a P. aeruginosa mCTX::PpqsA-lux chromosomal promoter fusion, to identify a series of new PqsR antagonists. The hit compounds inhibited pyocyanin and alkylquinolone signal molecule production in P. aeruginosa PAO1-L and PA14 strains. The inhibitor Ia, which showed the highest activity in PA14, reduced biofilm formation in PAO1-L and PA14, increasing their sensitivity to tobramycin. Furthermore, the hepatic and plasma stabilities for these compounds were determined in both rat and human in vitro microsomal assays, to gain a further understanding of their therapeutic potential. This work has uncovered a new class of P. aeruginosa PqsR antagonists with potential for hit to lead optimisation in the search for quorum sensing inhibitors for future anti-infective drug discovery programs.
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Affiliation(s)
- Fadi Soukarieh
- School of Life Sciences, Centre for Biomolecular Sciences, University of Nottingham, Nottingham NG7 2RD, UK; (F.S.); (E.V.O.); (J.-F.D.); (J.G.); (N.H.); (S.H.); (P.W.)
| | - Eduard Vico Oton
- School of Life Sciences, Centre for Biomolecular Sciences, University of Nottingham, Nottingham NG7 2RD, UK; (F.S.); (E.V.O.); (J.-F.D.); (J.G.); (N.H.); (S.H.); (P.W.)
| | - Jean-Frédéric Dubern
- School of Life Sciences, Centre for Biomolecular Sciences, University of Nottingham, Nottingham NG7 2RD, UK; (F.S.); (E.V.O.); (J.-F.D.); (J.G.); (N.H.); (S.H.); (P.W.)
| | - Janice Gomes
- School of Life Sciences, Centre for Biomolecular Sciences, University of Nottingham, Nottingham NG7 2RD, UK; (F.S.); (E.V.O.); (J.-F.D.); (J.G.); (N.H.); (S.H.); (P.W.)
| | - Nigel Halliday
- School of Life Sciences, Centre for Biomolecular Sciences, University of Nottingham, Nottingham NG7 2RD, UK; (F.S.); (E.V.O.); (J.-F.D.); (J.G.); (N.H.); (S.H.); (P.W.)
| | - Maria de Pilar Crespo
- Department of Microbiology, Universidad del Valle and Departamento of Biomedical Sciences, Universidad Santiago de Cali, Cali AA 760035, Colombia;
| | - Jonathan Ramírez-Prada
- Department of Chemistry, Universidad del Valle, Cali AA 25360, Colombia; (J.R.-P.); (B.I.); (R.A.); (J.Q.)
| | - Braulio Insuasty
- Department of Chemistry, Universidad del Valle, Cali AA 25360, Colombia; (J.R.-P.); (B.I.); (R.A.); (J.Q.)
| | - Rodrigo Abonia
- Department of Chemistry, Universidad del Valle, Cali AA 25360, Colombia; (J.R.-P.); (B.I.); (R.A.); (J.Q.)
| | - Jairo Quiroga
- Department of Chemistry, Universidad del Valle, Cali AA 25360, Colombia; (J.R.-P.); (B.I.); (R.A.); (J.Q.)
| | - Stephan Heeb
- School of Life Sciences, Centre for Biomolecular Sciences, University of Nottingham, Nottingham NG7 2RD, UK; (F.S.); (E.V.O.); (J.-F.D.); (J.G.); (N.H.); (S.H.); (P.W.)
| | - Paul Williams
- School of Life Sciences, Centre for Biomolecular Sciences, University of Nottingham, Nottingham NG7 2RD, UK; (F.S.); (E.V.O.); (J.-F.D.); (J.G.); (N.H.); (S.H.); (P.W.)
| | - Michael J. Stocks
- School of Pharmacy, Centre for Biomolecular Sciences, University of Nottingham, Nottingham NG7 2RD, UK;
| | - Miguel Cámara
- School of Life Sciences, Centre for Biomolecular Sciences, University of Nottingham, Nottingham NG7 2RD, UK; (F.S.); (E.V.O.); (J.-F.D.); (J.G.); (N.H.); (S.H.); (P.W.)
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Kitao T, Lepine F, Babloudi S, Walte F, Steinbacher S, Maskos K, Blaesse M, Negri M, Pucci M, Zahler B, Felici A, Rahme LG. Molecular Insights into Function and Competitive Inhibition of Pseudomonas aeruginosa Multiple Virulence Factor Regulator. mBio 2018; 9:e02158-17. [PMID: 29339431 DOI: 10.1128/mBio.02158-17] [Citation(s) in RCA: 46] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
New approaches to antimicrobial drug discovery are urgently needed to combat intractable infections caused by multidrug-resistant (MDR) bacteria. Multiple virulence factor regulator (MvfR or PqsR), a Pseudomonas aeruginosa quorum sensing transcription factor, regulates functions important in both acute and persistent infections. Recently identified non-ligand-based benzamine-benzimidazole (BB) inhibitors of MvfR suppress both acute and persistent P. aeruginosa infections in mice without perturbing bacterial growth. Here, we elucidate the crystal structure of the MvfR ligand binding domain (LBD) in complex with one potent BB inhibitor, M64. Structural analysis indicated that M64 binds, like native ligands, to the MvfR hydrophobic cavity. A hydrogen bond and pi interaction were found to be important for MvfR-M64 affinity. Surface plasmon resonance analysis demonstrated that M64 is a competitive inhibitor of MvfR. Moreover, a protein engineering approach revealed that Gln194 and Tyr258 are critical for the interaction between MvfR and M64. Random mutagenesis of the full-length MvfR protein identified a single-amino-acid substitution, I68F, at a DNA binding linker domain that confers M64 insensitivity. In the presence of M64, I68F but not the wild-type (WT) MvfR protein retained DNA binding ability. Our findings strongly suggest that M64 promotes conformational change at the DNA binding domain of MvfR and that the I68F mutation may compensate for this change, indicating allosteric inhibition. This work provides critical new insights into the molecular mechanism of MvfR function and inhibition that could aid in the optimization of anti-MvfR compounds and improve our understanding of MvfR regulation. Pseudomonas aeruginosa is an opportunistic Gram-negative pathogen that causes serious acute, persistent, and relapsing infections. New approaches to antimicrobial drug discovery are urgently needed to combat intractable infections caused by this pathogen. The Pseudomonas aeruginosa quorum sensing transcription factor MvfR regulates functions important in both acute and persistent infections. We used recently identified inhibitors of MvfR to perform structural studies and reveal important insights that would benefit the optimization of anti-MvfR compounds. Altogether, the results reported here provide critical detailed mechanistic insights into the function of MvfR domains that may benefit the optimization of the chemical, pharmacological, and safety properties of MvfR antagonist series.
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Maura D, Rahme LG. Pharmacological Inhibition of the Pseudomonas aeruginosa MvfR Quorum-Sensing System Interferes with Biofilm Formation and Potentiates Antibiotic-Mediated Biofilm Disruption. Antimicrob Agents Chemother 2017; 61:e01362-17. [PMID: 28923875 DOI: 10.1128/AAC.01362-17] [Citation(s) in RCA: 54] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2017] [Accepted: 09/14/2017] [Indexed: 12/18/2022] Open
Abstract
Pseudomonas aeruginosa biofilms contribute to its survival on biotic and abiotic surfaces and represent a major clinical threat due to their high tolerance to antibiotics. Therefore, the discovery of antibiofilm agents may hold great promise. We show that pharmacological inhibition of the P. aeruginosa quorum-sensing regulator MvfR (PqsR) using a benzamide-benzimidazole compound interferes with biofilm formation and potentiates biofilm sensitivity to antibiotics. Such a strategy could have great potential against P. aeruginosa persistence in diverse environments.
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