1
|
Deshamukhya C, Das BJ, Paul D, Dhar Chanda D, Bhattacharjee A. Imipenem and meropenem influence the Las/Rhl quorum-sensing systems in clinical isolates of Pseudomonas aeruginosa. Lett Appl Microbiol 2023; 76:ovad084. [PMID: 37496211 DOI: 10.1093/lambio/ovad084] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2023] [Revised: 07/12/2023] [Accepted: 07/25/2023] [Indexed: 07/28/2023]
Abstract
The present study was conducted to study the influence of imipenem and meropenem at subinhibitory concentration on the transcriptional response of Las/Rhl quorum-sensing systems in isolates of Pseudomonas aeruginosa. In the present study, six representative carbapenem nonsusceptible clinical isolates of P. aeruginosa were obtained. The agar dilution method was used to determine the minimum inhibitory concentration against imipenem and meropenem. The bacterial isolates were then cultured up to the early log phase in fresh Luria Bertani (LB) broths at 37°C with and without 2 µg mL-1 imipenem and meropenem, respectively. mRNA was then isolated from the bacterial isolates and was immediately reverse-transcribed to cDNA. The relative quantity of the expression of the lasI, lasR, rhlI, and rhlR genes was assessed by quantitative real-time Polymerase Chain Reaction (PCR) using the ΔΔCt method. The transcriptional response of the lasI and lasR genes was upregulated at subinhibitory concentration of meropenem. In contrast, the transcriptional response of the lasI, lasR, and rhlR genes was downregulated at subinhibitory concentration of imipenem as compared to the expression in untreated isolates. The data obtained in the current study showcased the ability of imipenem and meropenem to influence the response of the quorum-sensing genes at subinhibitory concentration.
Collapse
Affiliation(s)
| | - Bhaskar J Das
- Department of Microbiology, Assam University, Silchar 788011, India
| | - Deepjyoti Paul
- Department of Microbiology, Assam University, Silchar 788011, India
| | - Debadatta Dhar Chanda
- Department of Microbiology, Silchar Medical College and Hospital, Silchar 788014, India
| | | |
Collapse
|
2
|
Wang S, Zhao C, Xue B, Li C, Zhang X, Yang X, Li Y, Yang Y, Shen Z, Wang J, Qiu Z. Nanoalumina triggers the antibiotic persistence of Escherichia coli through quorum sensing regulators lrsF and qseB. JOURNAL OF HAZARDOUS MATERIALS 2022; 436:129198. [PMID: 35739728 DOI: 10.1016/j.jhazmat.2022.129198] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/28/2022] [Revised: 05/13/2022] [Accepted: 05/19/2022] [Indexed: 06/15/2023]
Abstract
Nanomaterials with bactericidal effects might provide novel strategies against bacteria. However, some bacteria can survive despite the exposure to nanomaterials, which challenges the safety of antibacterial nanomaterials. Here, we used a high dose of antibiotics to kill the E. coli. that survived under different concentrations of nanoalumina treatment to screen persisters, and found that nanoalumina could significantly trigger persisters formation. Treatment with 50 mg/L nanoalumina for 4 h resulted in the formation of (0.084 ± 0.005) % persisters. Both reactive oxygen species (ROS) and toxin-antitoxin (TA) system were involved in persisters formation. Interestingly, RT-PCR analysis and knockout of the five genes related to ROS and TA confirmed that only hipB was associated with the formation of persisters, suggesting the involvement of other mechanisms. We further identified 73 differentially expressed genes by transcriptome sequencing and analyzed them with bioinformatics tools. We selected six candidate genes and verified that five of them closely related to quorum sensing (QS) that were involved in persisters formation, and further validated that the coexpression of QS factors lrsF and qseB was a novel pathway for persisters. Our findings provided a better understanding on the emergence of bacterial persistence and the microbial behavior under nanomaterials exposure.
Collapse
Affiliation(s)
- Shang Wang
- Department of Hygienic Toxicology And Environmental Hygiene, Tianjin Institute of Environmental and Operational Medicine, Tianjin 300050, China; Key Laboratory of Risk Assessment and Control for Environment & Food Safety, Tianjin 300050, China
| | - Chen Zhao
- Department of Hygienic Toxicology And Environmental Hygiene, Tianjin Institute of Environmental and Operational Medicine, Tianjin 300050, China; Key Laboratory of Risk Assessment and Control for Environment & Food Safety, Tianjin 300050, China
| | - Bin Xue
- Department of Hygienic Toxicology And Environmental Hygiene, Tianjin Institute of Environmental and Operational Medicine, Tianjin 300050, China
| | - Chenyu Li
- Department of Hygienic Toxicology And Environmental Hygiene, Tianjin Institute of Environmental and Operational Medicine, Tianjin 300050, China
| | - Xi Zhang
- Department of Hygienic Toxicology And Environmental Hygiene, Tianjin Institute of Environmental and Operational Medicine, Tianjin 300050, China
| | - Xiaobo Yang
- Department of Hygienic Toxicology And Environmental Hygiene, Tianjin Institute of Environmental and Operational Medicine, Tianjin 300050, China
| | - Yan Li
- Department of Hygienic Toxicology And Environmental Hygiene, Tianjin Institute of Environmental and Operational Medicine, Tianjin 300050, China
| | - Yanping Yang
- Department of Hygienic Toxicology And Environmental Hygiene, Tianjin Institute of Environmental and Operational Medicine, Tianjin 300050, China
| | - Zhiqiang Shen
- Department of Hygienic Toxicology And Environmental Hygiene, Tianjin Institute of Environmental and Operational Medicine, Tianjin 300050, China; Key Laboratory of Risk Assessment and Control for Environment & Food Safety, Tianjin 300050, China
| | - Jingfeng Wang
- Department of Hygienic Toxicology And Environmental Hygiene, Tianjin Institute of Environmental and Operational Medicine, Tianjin 300050, China; Key Laboratory of Risk Assessment and Control for Environment & Food Safety, Tianjin 300050, China
| | - Zhigang Qiu
- Department of Hygienic Toxicology And Environmental Hygiene, Tianjin Institute of Environmental and Operational Medicine, Tianjin 300050, China.
| |
Collapse
|
3
|
Nolan C, Behrends V. Sub-Inhibitory Antibiotic Exposure and Virulence in Pseudomonas aeruginosa. Antibiotics (Basel) 2021; 10:antibiotics10111393. [PMID: 34827331 PMCID: PMC8615142 DOI: 10.3390/antibiotics10111393] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2021] [Revised: 11/09/2021] [Accepted: 11/10/2021] [Indexed: 12/20/2022] Open
Abstract
Pseudomonas aeruginosa is a prime opportunistic pathogen, one of the most important causes of hospital-acquired infections and the major cause of morbidity and mortality in cystic fibrosis lung infections. One reason for the bacterium's pathogenic success is the large array of virulence factors that it can employ. Another is its high degree of intrinsic and acquired resistance to antibiotics. In this review, we first summarise the current knowledge about the regulation of virulence factor expression and production. We then look at the impact of sub-MIC antibiotic exposure and find that the virulence-antibiotic interaction for P. aeruginosa is antibiotic-specific, multifaceted, and complex. Most studies undertaken to date have been in vitro assays in batch culture systems, involving short-term (<24 h) antibiotic exposure. Therefore, we discuss the importance of long-term, in vivo-mimicking models for future work, particularly highlighting the need to account for bacterial physiology, which by extension governs both virulence factor expression and antibiotic tolerance/resistance.
Collapse
|
4
|
Naga NG, El-Badan DE, Rateb HS, Ghanem KM, Shaaban MI. Quorum Sensing Inhibiting Activity of Cefoperazone and Its Metallic Derivatives on Pseudomonas aeruginosa. Front Cell Infect Microbiol 2021; 11:716789. [PMID: 34660340 PMCID: PMC8515130 DOI: 10.3389/fcimb.2021.716789] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2021] [Accepted: 09/15/2021] [Indexed: 12/20/2022] Open
Abstract
The last decade has witnessed a massive increase in the rate of mortalities caused by multidrug-resistant Pseudomonas aeruginosa. Therefore, developing new strategies to control virulence factors and pathogenicity has received much attention. One of these strategies is quorum sensing inhibition (QSI) which was developed to control Pseudomonas infection. This study aims to validate the effect of one of the most used β-lactam antibiotics; cefoperazone (CFP) and its metallic-derivatives on quorum sensing (QS) and virulence factors of P. aeruginosa. Assessment of quorum sensing inhibitory activity of CFP, cefoperazone Iron complex (CFPF) and cefoperazone Cobalt complex (CFPC) was performed by using reporter strain Chromobacterium violaceum ATCC 12472. Minimal inhibitory concentration (MIC) was carried out by the microbroth dilution method. The influence of sub-MICs (1/4 and 1/2 MICs) of CFP, CFPF and CFPC on virulence factors of P. aeruginosa was evaluated. Data was confirmed on the molecular level by RT-PCR. Also, molecular docking analysis was conducted to figure out the possible mechanisms of QSI. CFP, CFPF, and CFPC inhibited violacein pigment production of C. violaceum ATCC 12472. Sub-MICs of CFP (128- 256 μg/mL), and significantly low concentrations of CFPC (0.5- 16 μg/mL) and CFPF (0.5- 64 μg/mL) reduced the production of QS related virulence factors such as pyocyanin, protease, hemolysin and eliminated biofilm assembly by P. aeruginosa standard strains PAO1 and PA14, and P. aeruginosa clinical isolates Ps1, Ps2, and Ps3, without affecting bacterial viability. In addition, CFP, CFPF, and CFPC significantly reduced the expression of lasI and rhlI genes. The molecular docking analysis elucidated that the QS inhibitory effect was possibly caused by the interaction with QS receptors. Both CFPF and CFPC interacted strongly with LasI, LasR and PqsR receptors with a much high ICM scores compared to CFP that could be the cause of elimination of natural ligand binding. Therefore, CFPC and CFPF are potent inhibitors of quorum sensing signaling and virulence factors of P. aeruginosa.
Collapse
Affiliation(s)
- Nourhan G Naga
- Department of Botany and Microbiology, Faculty of Science, Alexandria University, Alexandria, Egypt
| | - Dalia E El-Badan
- Department of Botany and Microbiology, Faculty of Science, Alexandria University, Alexandria, Egypt
| | - Heba S Rateb
- Department of Pharmaceutical and Medicinal Chemistry, Pharmacy College, Misr University for Science and Technology, Cairo, Egypt
| | - Khaled M Ghanem
- Department of Botany and Microbiology, Faculty of Science, Alexandria University, Alexandria, Egypt
| | - Mona I Shaaban
- Department of Microbiology and Immunology, Faculty of Pharmacy, Mansoura University, Mansoura, Egypt
| |
Collapse
|
5
|
Inchagova KS, Duskaev GK, Deryabin DG. Quorum Sensing Inhibition in Chromobacterium violaceum by Amikacin Combination with Activated Charcoal or Small Plant-Derived Molecules (Pyrogallol and Coumarin). Microbiology (Reading) 2019. [DOI: 10.1134/s0026261719010132] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
|
6
|
Deryabin DG, Inchagova KS. Inhibitory effect of aminoglycosides and tetracyclines on quorum sensing in Chromobacterium violaceum. Microbiology (Reading) 2018. [DOI: 10.1134/s002626171801006x] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023] Open
|
7
|
Deryabin DG, Inchagova KS. Subinhibitory concentrations of the penicillin antibiotics induce quorum-dependent violacein synthesis in Chromobacterium violaceum. Microbiology (Reading) 2017. [DOI: 10.1134/s0026261717040051] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
|
8
|
El-Mowafy SA, Abd El Galil KH, Habib ESE, Shaaban MI. Quorum sensing inhibitory activity of sub-inhibitory concentrations of β-lactams. Afr Health Sci 2017; 17:199-207. [PMID: 29026394 DOI: 10.4314/ahs.v17i1.25] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
INTRODUCTION The virulence factors of Pseudomonas aeruginosa are under the control of quorum sensing (QS) signals. Hence, interference with QS prevents its pathogenesis. OBJECTIVE The aim of the present research is to assess the influence of some β-lactam antibiotics on cell communication and the release of different virulence factors. METHODS The minimal inhibitory concentrations of ceftazidime, cefepime and imipenem were evaluated by microbroth dilution method. The effect of sub-inhibitory concentration of the tested antibiotics on QS signals was investigated using reporter strain assay. In addition, different virulence factors (elastase, protease, pyocyanin and hemolysin) were estimated in the presence of their sub-inhibitory concentrations. RESULTS Low concentrations of ceftazidime, cefepime and imipenem caused significant elimination of the QS signals 3OH-C12-HSL and C4-HSL up to 1/20 MIC. Furthermore, low concentrations of the tested antimicrobials suppressed virulence factors elastase and hemolysin. Moreover, 1/20 of their MICs reduced elastase, protease, pyocyanin and hemolysin. CONCLUSION Utilization of β-lactam antibiotics at low concentrations could be an effective approach for prevention and treatment of P. aeruginosa infection.
Collapse
Affiliation(s)
- Somaia A El-Mowafy
- Microbiology Department, Faculty of Pharmacy, Mansoura University, Mansoura, 35516 Egypt
| | - Khaled H Abd El Galil
- Pharmaceutical Sciences Department, Faculty of Pharmacy, Beirut Arab University, Beirut, Lebanon. Department of Microbiology and Immunology, Faculty of Pharmacy, Mansoura University, Mansoura, 35516 Egypt
| | - El-Sayed E Habib
- Department of Pharmaceutics and Pharmaceutical Biotechnology, Faculty of Pharmacy, Taibah University, Al Madinah Al Munawwarah 30078, Saudi Arabia. Department of Microbiology and Immunology, Faculty of Pharmacy, Mansoura University, Mansoura, 35516 Egypt
| | - Mona I Shaaban
- Department of Pharmaceutics and Pharmaceutical Biotechnology, Faculty of Pharmacy, Taibah University, Al Madinah Al Munawwarah 30078, Saudi Arabia. Department of Microbiology and Immunology, Faculty of Pharmacy, Mansoura University, Mansoura, 35516 Egypt
| |
Collapse
|
9
|
Barr HL, Halliday N, Cámara M, Barrett DA, Williams P, Forrester DL, Simms R, Smyth AR, Honeybourne D, Whitehouse JL, Nash EF, Dewar J, Clayton A, Knox AJ, Fogarty AW. Pseudomonas aeruginosa quorum sensing molecules correlate with clinical status in cystic fibrosis. Eur Respir J 2015; 46:1046-54. [PMID: 26022946 PMCID: PMC4589431 DOI: 10.1183/09031936.00225214] [Citation(s) in RCA: 78] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2014] [Accepted: 04/08/2015] [Indexed: 01/25/2023]
Abstract
Pseudomonas aeruginosa produces quorum sensing signal molecules that are potential biomarkers for infection. A prospective study of 60 cystic fibrosis patients with chronic P. aeruginosa, who required intravenous antibiotics for pulmonary exacerbations, was undertaken. Clinical measurements and biological samples were obtained at the start and end of the treatment period. Additional data were available for 29 of these patients when they were clinically stable. Cross-sectionally, quorum sensing signal molecules were detectable in the sputum, plasma and urine of 86%, 75% and 83% patients, respectively. They were positively correlated between the three biofluids. Positive correlations were observed for most quorum sensing signal molecules in sputum, plasma and urine, with quantitative measures of pulmonary P. aeruginosa load at the start of a pulmonary exacerbation. Plasma concentrations of 2-nonyl-4-hydroxy-quinoline (NHQ) were significantly higher at the start of a pulmonary exacerbation compared to clinical stability (p<0.01). Following the administration of systemic antibiotics, plasma 2-heptyl-4-hydroxyquinoline (p=0.02) and NHQ concentrations (p<0.01) decreased significantly. In conclusion, quorum sensing signal molecules are detectable in cystic fibrosis patients with pulmonary P. aeruginosa infection and are positively correlated with quantitative measures of P. aeruginosa. NHQ correlates with clinical status and has potential as a novel biomarker for P. aeruginosa infection. P. aeruginosa QS molecules correlate with clinical status in cystic fibrosis and are biomarkers for infectionhttp://ow.ly/MhzZp
Collapse
Affiliation(s)
- Helen L Barr
- Division of Respiratory Medicine, Clinical Sciences Building, University of Nottingham, City Hospital Campus, Nottingham, UK
| | - Nigel Halliday
- School of Life Sciences, Centre for Biomolecular Sciences, University of Nottingham, Nottingham, UK
| | - Miguel Cámara
- School of Life Sciences, Centre for Biomolecular Sciences, University of Nottingham, Nottingham, UK
| | - David A Barrett
- Centre for Analytical Bioscience, School of Pharmacy, University of Nottingham, Nottingham, UK
| | - Paul Williams
- School of Life Sciences, Centre for Biomolecular Sciences, University of Nottingham, Nottingham, UK
| | - Douglas L Forrester
- Division of Respiratory Medicine, Clinical Sciences Building, University of Nottingham, City Hospital Campus, Nottingham, UK
| | - Rebecca Simms
- Division of Respiratory Medicine, Clinical Sciences Building, University of Nottingham, City Hospital Campus, Nottingham, UK
| | - Alan R Smyth
- Division of Child Health, Obstetrics and Gynaecology, University of Nottingham, University Hospital, Nottingham, UK
| | - David Honeybourne
- West Midlands Adult CF Centre, Heart of England NHS Foundation Trust, Birmingham, UK
| | - Joanna L Whitehouse
- West Midlands Adult CF Centre, Heart of England NHS Foundation Trust, Birmingham, UK
| | - Edward F Nash
- West Midlands Adult CF Centre, Heart of England NHS Foundation Trust, Birmingham, UK
| | - Jane Dewar
- Dept of Respiratory Medicine, Nottingham University Hospitals NHS Trust, Nottingham, UK
| | - Andrew Clayton
- Dept of Respiratory Medicine, Nottingham University Hospitals NHS Trust, Nottingham, UK
| | - Alan J Knox
- Division of Respiratory Medicine, Clinical Sciences Building, University of Nottingham, City Hospital Campus, Nottingham, UK
| | - Andrew W Fogarty
- Divison of Epidemiology and Public Health, Clinical Sciences Building, University of Nottingham, Nottingham, UK
| |
Collapse
|
10
|
Antipseudomonal agents exhibit differential pharmacodynamic interactions with human polymorphonuclear leukocytes against established biofilms of Pseudomonas aeruginosa. Antimicrob Agents Chemother 2015; 59:2198-205. [PMID: 25645829 DOI: 10.1128/aac.04934-14] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Pseudomonas aeruginosa is the most common pathogen infecting the lower respiratory tract of cystic fibrosis (CF) patients, where it forms tracheobronchial biofilms. Pseudomonas biofilms are refractory to antibacterials and to phagocytic cells with innate immunity, leading to refractory infection. Little is known about the interaction between antipseudomonal agents and phagocytic cells in eradication of P. aeruginosa biofilms. Herein, we investigated the capacity of three antipseudomonal agents, amikacin (AMK), ceftazidime (CAZ), and ciprofloxacin (CIP), to interact with human polymorphonuclear leukocytes (PMNs) against biofilms and planktonic cells of P. aeruginosa isolates recovered from sputa of CF patients. Three of the isolates were resistant and three were susceptible to each of these antibiotics. The concentrations studied (2, 8, and 32 mg/liter) were subinhibitory for biofilms of resistant isolates, whereas for biofilms of susceptible isolates, they ranged between sub-MIC and 2 × MIC values. The activity of each antibiotic alone or in combination with human PMNs against 48-h mature biofilms or planktonic cells was determined by XTT [2,3-bis(2-methoxy-4-nitro-5-sulfophenyl)-2H-tetrazolium-5-carboxanilide] assay. All combinations of AMK with PMNs resulted in synergistic or additive effects against planktonic cells and biofilms of P. aeruginosa isolates compared to each component alone. More than 75% of CAZ combinations exhibited additive interactions against biofilms of P. aeruginosa isolates, whereas CIP had mostly antagonistic interaction or no interaction with PMNs against biofilms of P. aeruginosa. Our findings demonstrate a greater positive interaction between AMK with PMNs than that observed for CAZ and especially CIP against isolates of P. aeruginosa from the respiratory tract of CF patients.
Collapse
|
11
|
Wu D, Huang W, Duan Q, Li F, Cheng H. Sodium houttuyfonate affects production of N-acyl homoserine lactone and quorum sensing-regulated genes expression in Pseudomonas aeruginosa. Front Microbiol 2014; 5:635. [PMID: 25505457 PMCID: PMC4244979 DOI: 10.3389/fmicb.2014.00635] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2014] [Accepted: 11/05/2014] [Indexed: 12/11/2022] Open
Abstract
Quorum sensing (QS) is a means of cell-to-cell communication that uses diffusible signaling molecules that are sensed by the population to determine population density, thus allowing co-ordinate gene regulation in response to population density. In Pseudomonas aeruginosa, production of the QS signaling molecule, N-acyl homoserine lactone (AHL), co-ordinates expression of key factors of pathogenesis, including biofilm formation and toxin secretion. It is predicted that the inhibition of AHL sensing would provide an effective clinical treatment to reduce the expression of virulence factors and increase the effectiveness of antimicrobial agents. We previously demonstrated that sodium houttuyfonate (SH), commonly used in traditional Chinese medicine to treat infectious diseases, can effectively inhibit QS-regulated processes, including biofilm formation. Here, using a model system, we demonstrate that SH causes the dose-dependent inhibition of AHL production, through down-regulation of the AHL biosynthesis gene, lasI. Addition of SH also resulted in down-regulation of expression of the AHL sensor and transcriptional regulator, LasR, and inhibited the production of the QS-regulated virulence factors, pyocyanin and LasA. These results suggest that the antimicrobial activity of SH may be due to its ability to disrupt QS in P. aeruginosa.
Collapse
Affiliation(s)
- Daqiang Wu
- Laboratory of Microbiology and Immunology, School of Chinese and Western Integrative Medicine, Anhui University of Chinese Medicine Hefei, China
| | - Weifeng Huang
- Laboratory of Microbiology and Immunology, School of Chinese and Western Integrative Medicine, Anhui University of Chinese Medicine Hefei, China
| | - Qiangjun Duan
- Laboratory of Microbiology and Immunology, School of Chinese and Western Integrative Medicine, Anhui University of Chinese Medicine Hefei, China
| | - Fang Li
- School of Pharmacy, Anhui University of Chinese Medicine Hefei, China
| | - Huijuan Cheng
- Laboratory of Microbiology and Immunology, School of Chinese and Western Integrative Medicine, Anhui University of Chinese Medicine Hefei, China
| |
Collapse
|
12
|
Chaudhari V, Gosai H, Raval S, Kothari V. Effect of certain natural products and organic solvents on quorum sensing in Chromobacterium violaceum. ASIAN PAC J TROP MED 2014; 7S1:S204-11. [DOI: 10.1016/s1995-7645(14)60233-9] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2014] [Revised: 06/05/2014] [Accepted: 06/15/2014] [Indexed: 10/24/2022] Open
|
13
|
March Rosselló GA, Eiros Bouza JM. [Quorum sensing in bacteria and yeast]. Med Clin (Barc) 2013; 141:353-7. [PMID: 23622893 DOI: 10.1016/j.medcli.2013.02.031] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2012] [Revised: 02/01/2013] [Accepted: 02/21/2013] [Indexed: 12/31/2022]
Abstract
Bacterial sets are complex dynamic systems, which interact with each other and through the interaction, bacteria coexist, collaborate, compete and share information in a coordinated manner. A way of bacterial communication is quorum sensing. Through this mechanism the bacteria can recognize its concentration in a given environment and they can decide the time at which the expression of a particular set of genes should be started for developing a specific and simultaneous response. The result of these interconnections raises properties that cannot be explained from a single isolated bacterial cell.
Collapse
|
14
|
Fulghesu L, Giallorenzo C, Savoia D. Evaluation of Different Compounds as Quorum Sensing Inhibitors inPseudomonas aeruginosa. J Chemother 2013; 19:388-91. [PMID: 17855182 DOI: 10.1179/joc.2007.19.4.388] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Quorum sensing (QS) controls systems affecting the pathogenicity of many microorganisms; its interruption has an anti-pathogenic effect and can be used in the treatment of bacterial infections. In this study we evaluated QS regulation by Pseudomonas aeruginosa strains and QS inhibition (QSI) by different compounds. The inhibitory activity of 3 macrolide and 3 lincosamide drugs, resveratrol, garlic extract and N-acetylcysteine was tested on 4 P. aeruginosa strains isolated from cystic fibrosis (CF) patients using Chromobacterium violaceum ATCC 12472 as biomonitor. One P. aeruginosa strain, lincomycin and N-acetylcysteine did not show QSI, contrary to other compounds and P. aeruginosa strains. These results indicate that QSI evaluation should be taken into account in the design of new therapeutic strategies to treat P. aeruginosa infections, especially in patients infected by antibiotic-resistant bacteria.
Collapse
Affiliation(s)
- L Fulghesu
- Department of Clinical and Biological Sciences, University of Turin, Italy
| | | | | |
Collapse
|
15
|
Wang H, Tu F, Gui Z, Lu X, Chu W. Antibiotic resistance profiles and quorum sensing-dependent virulence factors in clinical isolates of pseudomonas aeruginosa. Indian J Microbiol 2013; 53:163-7. [PMID: 24426103 PMCID: PMC3626956 DOI: 10.1007/s12088-013-0370-7] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2013] [Accepted: 01/30/2013] [Indexed: 11/27/2022] Open
Abstract
Pseudomonas aeruginosa produces multiple virulence factors that have been associated with quorum sensing. The aim of this study was to evaluate the prevalence of drug resistant profiles and quorum sensing related virulence factors. Pseudomonas aeruginosa were collected from different patients hospitalized in China, the isolates were tested for their susceptibility to different common antimicrobial drugs and detected QS-related virulence factors. We identified 170 isolates displaying impaired phenotypic activity, approximately 80 % of the isolates were found to exhibit the QS-dependent phenotypes, among them, 12 isolates were defective in AHLs production, and therefore considered QS-deficient strains. Resistance was most often observed to Cefazolin (81.2 %), followed by trimethoprim-sulfamethoxazole (73.5 %), ceftriaxone (62.4 %) and Cefotaxime, Levofloxacin, Ciprofloxacin (58.8 %), and to a lesser extent Meropenem (20.0 %), Cefepime (18.8 %), and Cefoperazone/sulbactam (2.4 %) The QS-deficient isolates that were negative for virulence factor production were generally less susceptible to the antimicrobials. The results showed a high incidences of antibiotic resistance and virulence properties in P. aeruginosa, and indicate that the clinical use of QS-inhibitory drugs that appear superior to conventional antimicrobials by not exerting any selective pressure on resistant strains.
Collapse
Affiliation(s)
- Huafu Wang
- />Lishui People’s Hospital, Lishui, 323000 China
| | - Faping Tu
- />Affiliated Hospital of North Sichuan Medical College, Nanchong, 637000 China
| | - Zhihong Gui
- />Lishui People’s Hospital, Lishui, 323000 China
| | - Xianghong Lu
- />Lishui People’s Hospital, Lishui, 323000 China
| | - Weihua Chu
- />Department of Microbiology, School of Life Science and Technology, China Pharmaceutical University, Nanjing, 210009 China
| |
Collapse
|
16
|
The apparent quorum-sensing inhibitory activity of pyrogallol is a side effect of peroxide production. Antimicrob Agents Chemother 2013; 57:2870-3. [PMID: 23545532 DOI: 10.1128/aac.00401-13] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
There currently is more and more interest in the use of natural products, such as tea polyphenols, as therapeutic agents. The polyphenol compound pyrogallol has been reported before to inhibit quorum-sensing-regulated bioluminescence in Vibrio harveyi. Here, we report that the addition of 10 mg · liter(-1) pyrogallol protects both brine shrimp (Artemia franciscana) and giant river prawn (Macrobrachium rosenbergii) larvae from pathogenic Vibrio harveyi, whereas the compound showed relatively low toxicity (therapeutic index of 10). We further demonstrate that the apparent quorum-sensing-disrupting activity is a side effect of the peroxide-producing activity of this compound rather than true quorum-sensing inhibition. Our results emphasize that verification of minor toxic effects by using sensitive methods and the use of appropriate controls are essential when characterizing compounds as being able to disrupt quorum sensing.
Collapse
|
17
|
Liu Z, Wang W, Zhu Y, Gong Q, Yu W, Lu X. Antibiotics at subinhibitory concentrations improve the quorum sensing behavior ofChromobacterium violaceum. FEMS Microbiol Lett 2013; 341:37-44. [DOI: 10.1111/1574-6968.12086] [Citation(s) in RCA: 51] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2012] [Revised: 12/28/2012] [Accepted: 01/16/2013] [Indexed: 01/25/2023] Open
|
18
|
Doxycycline interferes with quorum sensing-mediated virulence factors and biofilm formation in gram-negative bacteria. World J Microbiol Biotechnol 2013; 29:949-57. [PMID: 23299903 DOI: 10.1007/s11274-013-1252-1] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2012] [Accepted: 01/02/2013] [Indexed: 10/27/2022]
Abstract
Inhibition of quorum sensing (QS)-regulated virulence factors including biofilm is a recognized anti-pathogenic drug target. The search for safe and effective anti-QS agents is expected to be useful to combat diseases caused by multidrug-resistant bacteria. In this study, effect of a commonly used antibiotic, doxycycline on QS was evaluated using sensor strains of Chromobacterium violaceum (ATCC 12472 and CVO26) and Pseudomonas aeruginosa PAO1. Sub-MICs of doxycycline reduced QS-controlled violacein production in C. violaceum to a significant degree (70 %) and showed a significant reduction of LasB elastase (67.2 %), pyocyanin (69.1 %), chitinase (69.8 %) and protease (65 %) production and swarming motility (74 %) in P. aeruginosa PAO1 over untreated controls. Similar results were also recorded against a clinical strain of P. aeruginosa (PAF-79). Interestingly, doxycycline at respective sub-MICs (4 and 32 μg ml(-1)) significantly reduced the biofilm-forming capability and exopolysaccharide production in both the strains of P. aeruginosa (PAO1 and PAF-79) over untreated controls. The results of this study highlight the multiple actions of doxycycline against QS-linked traits/virulence factors and its potential to attenuate virulence of P. aeruginosa.
Collapse
|
19
|
Efficacy of liposomal bismuth-ethanedithiol-loaded tobramycin after intratracheal administration in rats with pulmonary Pseudomonas aeruginosa infection. Antimicrob Agents Chemother 2012; 57:569-78. [PMID: 23147741 DOI: 10.1128/aac.01634-12] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
We sought to investigate alterations in quorum-sensing signal molecule N-acyl homoserine lactone secretion and in the release of Pseudomonas aeruginosa virulence factors, as well as the in vivo antimicrobial activity of bismuth-ethanedithiol incorporated into a liposome-loaded tobramycin formulation (LipoBiEDT-TOB) administered to rats chronically infected with P. aeruginosa. The quorum-sensing signal molecule N-acyl homoserine lactone was monitored by using a biosensor organism. P. aeruginosa virulence factors were assessed spectrophotometrically. An agar beads model of chronic Pseudomonas lung infection in rats was used to evaluate the efficacy of the liposomal formulation in the reduction of bacterial count. The levels of active tobramycin in the lungs and the kidneys were evaluated by microbiological assay. LipoBiEDT-TOB was effective in disrupting both quorum-sensing signal molecules N-3-oxo-dodeccanoylhomoserine lactone and N-butanoylhomoserine lactone, as well as significantly (P < 0.05) reducing lipase, chitinase, and protease production. At 24 h after 3 treatments, the CFU counts in lungs of animals treated with LipoBiEDT-TOB were of 3 log(10) CFU/lung, comparated to 7.4 and 4.7 log(10) CFU/lung, respectively, in untreated lungs and in lungs treated with free antibiotic. The antibiotic concentration after the last dose of LipoBiEDT-TOB was 25.1 μg/lung, while no tobramycin was detected in the kidneys. As for the free antibiotic, we found 6.5 μg/kidney but could not detect any tobramycin in the lungs. Taken together, LipoBiEDT-TOB reduced the production of quorum-sensing molecules and virulence factors and could highly improve the management of chronic pulmonary infection in cystic fibrosis patients.
Collapse
|
20
|
Applications of small molecule activators and inhibitors of quorum sensing in Gram-negative bacteria. Trends Microbiol 2012; 20:449-58. [PMID: 22771187 DOI: 10.1016/j.tim.2012.06.003] [Citation(s) in RCA: 136] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2012] [Revised: 06/08/2012] [Accepted: 06/13/2012] [Indexed: 01/23/2023]
Abstract
Quorum sensing is a form of intercellular communication used by many species of bacteria that facilitates concerted interactions between the cells comprising a population. The phenotypes regulated by quorum sensing are extremely diverse, with many having a significant impact upon healthcare, agriculture, and the environment. Consequently there has been significant interest in developing methods to manipulate this signalling process and recent years have witnessed significant theoretical and practical developments. A wide range of small molecule modulators of quorum sensing systems has been discovered, providing an expansive chemical toolbox for the study and modulation of this signalling mechanism. In this review, a selection of recent case studies which illustrate the value of both activators and inhibitors of quorum sensing in Gram-negative bacteria are discussed.
Collapse
|
21
|
Shen L, Ma Y, Liang H. Characterization of a novel gene related to antibiotic susceptibility in Pseudomonas aeruginosa. J Antibiot (Tokyo) 2011; 65:59-65. [PMID: 22146126 DOI: 10.1038/ja.2011.111] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Pseudomonas aeruginosa is a human pathogen with increased intrinsic resistance to a large number of antibiotics used in clinical therapy. Therefore, understanding the mechanisms of resistance and developing therapy alternatives for P. aeruginosa are of profound importance. Previous work from our laboratory demonstrated that several mutants have isolated with altered expression of the phzA1B1C1D1E1F1G1 (phzA1) operon in the presence of sub-inhibitory concentrations (SICs) of tetracycline (TET). The present study investigates the roles of the PA0011 gene in mediating phzA1 expression at SIC of TET. The PA0011 gene encodes 2-OH-lauroytransferase by controlling the synthesis of the cell envelope and the outer membrane. We found that the PA0011 mutant strain was susceptible to several different antibiotics and environmental stresses. Complementation in the PA0011 mutant restored these phenotypes to wild-type levels. In addition, expression of the PA0011 gene, as monitored through a luciferase reporter, is increased at SICs of antibiotics. Indeed, the expression of the PA0011 gene increased about threefold in pqsR and pqsH mutants compared with the wild-type PAO1. However, the PA0011 gene negatively regulates the quorum sensing (QS) system. Taken together, these data suggest that PA0011 is involved in susceptibility to antimicrobial agents in P. aeruginosa, and that its susceptibility effect maybe partly dependent on increased QS expression.
Collapse
Affiliation(s)
- Lixin Shen
- Key Laboratory of Resources Biology and Biotechnology in Western China, Ministry of Education, Faculty of Life Sciences, Northwest University, Xi'an, China
| | | | | |
Collapse
|
22
|
Galloway WRJD, Hodgkinson JT, Bowden SD, Welch M, Spring DR. Quorum Sensing in Gram-Negative Bacteria: Small-Molecule Modulation of AHL and AI-2 Quorum Sensing Pathways. Chem Rev 2010; 111:28-67. [DOI: 10.1021/cr100109t] [Citation(s) in RCA: 454] [Impact Index Per Article: 32.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Affiliation(s)
- Warren R. J. D. Galloway
- Department of Chemistry and Department of Biochemistry, University of Cambridge, Cambridge, CB2 1EW U.K
| | - James T. Hodgkinson
- Department of Chemistry and Department of Biochemistry, University of Cambridge, Cambridge, CB2 1EW U.K
| | - Steven D. Bowden
- Department of Chemistry and Department of Biochemistry, University of Cambridge, Cambridge, CB2 1EW U.K
| | - Martin Welch
- Department of Chemistry and Department of Biochemistry, University of Cambridge, Cambridge, CB2 1EW U.K
| | - David R. Spring
- Department of Chemistry and Department of Biochemistry, University of Cambridge, Cambridge, CB2 1EW U.K
| |
Collapse
|
23
|
Babić F, Venturi V, Maravić-Vlahovicek G. Tobramycin at subinhibitory concentration inhibits the RhlI/R quorum sensing system in a Pseudomonas aeruginosa environmental isolate. BMC Infect Dis 2010; 10:148. [PMID: 20525206 PMCID: PMC2898818 DOI: 10.1186/1471-2334-10-148] [Citation(s) in RCA: 50] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2009] [Accepted: 06/02/2010] [Indexed: 12/22/2022] Open
Abstract
Background Antibiotics are not only small molecules with therapeutic activity in killing or inhibiting microbial growth, but can also act as signaling molecules affecting gene expression in bacterial communities. A few studies have demonstrated the effect of tobramycin as a signal molecule on gene expression at the transcriptional level and its effect on bacterial physiology and virulence. These have shown that subinhibitory concentrations (SICs) of tobramycin induce biofilm formation and enhance the capabilities of P. aeruginosa to colonize specific environments. Methods Environmental P. aeruginosa strain PUPa3 was grown in the presence of different concentrations of tobramycin and it was determined at which highest concentration SIC, growth, total protein levels and translation efficiency were not affected. At SIC it was then established if phenotypes related to cell-cell signaling known as quorum sensing were altered. Results In this study it was determined whether tobramycin sensing/response at SICs was affecting the two independent AHL QS systems in an environmental P. aeruginosa strain. It is reasonable to assume that P. aeruginosa encounters tobramycin in nature since it is produced by niche mate Streptomyces tenebrarius. It was established that SICs of tobramycin inhibited the RhlI/R system by reducing levels of C4-HSL production. This effect was not due to a decrease of rhlI transcription and required tobramycin-ribosome interaction. Conclusions Tobramycin signaling in P. aeruginosa occurs and different strains can have a different response. Understanding the tobramycin response by an environmental P. aeruginosa will highlight possible inter-species signalling taking place in nature and can possible also have important implications in the mode of utilization for human use of this very important antibiotic.
Collapse
Affiliation(s)
- Fedora Babić
- Department of Biochemistry and Molecular Biology, University of Zagreb, Croatia
| | | | | |
Collapse
|
24
|
Paradigm shift in discovering next-generation anti-infective agents: targeting quorum sensing, c-di-GMP signaling and biofilm formation in bacteria with small molecules. Future Med Chem 2010; 2:1005-35. [DOI: 10.4155/fmc.10.185] [Citation(s) in RCA: 112] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023] Open
Abstract
Small molecules that can attenuate bacterial toxin production or biofilm formation have the potential to solve the bacteria resistance problem. Although several molecules, which inhibit bacterial cell-to-cell communication (quorum sensing), biofilm formation and toxin production, have been discovered, there is a paucity of US FDA-approved drugs that target these processes. Here, we review the current understanding of quorum sensing in important pathogens such as Pseudomonas aeruginosa, Escherichia coli and Staphylococcus aureus and provide examples of experimental molecules that can inhibit both known and unknown targets in bacterial virulence factor production and biofilm formation. Structural data for protein targets that are involved in both quorum sensing and cyclic diguanylic acid signaling are needed to aid the development of molecules with drug-like properties in order to target bacterial virulence factors production and biofilm formation.
Collapse
|
25
|
Yang L, Rybtke MT, Jakobsen TH, Hentzer M, Bjarnsholt T, Givskov M, Tolker-Nielsen T. Computer-aided identification of recognized drugs as Pseudomonas aeruginosa quorum-sensing inhibitors. Antimicrob Agents Chemother 2009; 53:2432-43. [PMID: 19364871 PMCID: PMC2687250 DOI: 10.1128/aac.01283-08] [Citation(s) in RCA: 148] [Impact Index Per Article: 9.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2008] [Revised: 11/23/2008] [Accepted: 03/28/2009] [Indexed: 12/11/2022] Open
Abstract
Attenuation of Pseudomonas aeruginosa virulence by the use of small-molecule quorum-sensing inhibitors (referred to as the antipathogenic drug principle) is likely to play a role in future treatment strategies for chronic infections. In this study, structure-based virtual screening was used in a search for putative quorum-sensing inhibitors from a database comprising approved drugs and natural compounds. The database was built from compounds which showed structural similarities to previously reported quorum-sensing inhibitors, the ligand of the P. aeruginosa quorum-sensing receptor LasR, and a quorum-sensing receptor agonist. Six top-ranking compounds, all recognized drugs, were identified and tested for quorum-sensing-inhibitory activity. Three compounds, salicylic acid, nifuroxazide, and chlorzoxazone, showed significant inhibition of quorum-sensing-regulated gene expression and related phenotypes in a dose-dependent manner. These results suggest that the identified compounds have the potential to be used as antipathogenic drugs. Furthermore, the results indicate that structure-based virtual screening is an efficient tool in the search for novel compounds to combat bacterial infections.
Collapse
Affiliation(s)
- Liang Yang
- Department of Systems Biology, Technical University of Denmark, Lyngby, Denmark
| | | | | | | | | | | | | |
Collapse
|
26
|
Brackman G, Hillaert U, Van Calenbergh S, Nelis HJ, Coenye T. Use of quorum sensing inhibitors to interfere with biofilm formation and development in Burkholderia multivorans and Burkholderia cenocepacia. Res Microbiol 2009; 160:144-51. [DOI: 10.1016/j.resmic.2008.12.003] [Citation(s) in RCA: 98] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2008] [Revised: 12/09/2008] [Accepted: 12/10/2008] [Indexed: 12/11/2022]
|
27
|
Ni N, Li M, Wang J, Wang B. Inhibitors and antagonists of bacterial quorum sensing. Med Res Rev 2009; 29:65-124. [DOI: 10.1002/med.20145] [Citation(s) in RCA: 158] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
|
28
|
Modulation of secreted virulence factor genes by subinhibitory concentrations of antibiotics in Pseudomonas aeruginosa. J Microbiol 2008; 46:441-7. [PMID: 18758736 DOI: 10.1007/s12275-008-0054-x] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2008] [Accepted: 06/20/2008] [Indexed: 10/21/2022]
Abstract
Recent studies have shown that subinhibitory antibiotics play important roles in regulating bacterial genes including virulence factor genes. In this study, the expression of 13 secreted virulence related gene clusters of Pseudomonas aeruginosa, an important opportunistic pathogen, was examined in the presence of subinhibitory concentrations of 4 antibiotics: vancomycin, tetracycline, ampicillin and azithromycin. Activation of gene expression was observed with phzAl, rhlAB, phzA2, lasB, exoY, and exoS. Subinhibitory concentrations of vancomycin resulted in more than 10-fold increase of rhlAB and phzA2 transcription. Both rhamnolipid production and pyocyanin production were significantly elevated, correlating phenotypes with the increased transcription. P. aeruginosa swarming and swimming motility also increased. Similar results were observed with subinhibitory tetracycline, azithromycin and ampicillin. These results indicate that the antibiotics at low concentrations can up-regulate virulence factors and therefore influence bacterial pathogenesis.
Collapse
|
29
|
Bjarnsholt T, Givskov M. The role of quorum sensing in the pathogenicity of the cunning aggressor Pseudomonas aeruginosa. Anal Bioanal Chem 2006; 387:409-14. [PMID: 17019573 DOI: 10.1007/s00216-006-0774-x] [Citation(s) in RCA: 78] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2006] [Revised: 08/08/2006] [Accepted: 08/10/2006] [Indexed: 10/24/2022]
Abstract
Recent decades have revealed that many bacterial species are capable of communicating with each other, and this observation has been largely responsible for a paradigm shift in microbiology. Whereas it was previously believed that bacteria lived as individual cells, it is now acknowledged that bacteria preferentially live in communities in the form of primitive organisms in which the behavior of individual cells is coordinated by cell-cell communication, known as quorum sensing (QS). Bacteria use QS for regulation of the processes involved in their interaction with each other, their environment, and, particularly, higher organisms We have focused on Pseudomonas aeruginosa, an opportunistic pathogen producing more than 30 QS-regulated virulence factors. P. aeruginosa causes several types of nosocomial infection, and lung infection in cystic fibrosis (CF) patients. We review the role of QS in the protective mechanisms of P. aeruginosa and show how disruption of the QS can be used as an approach to control this cunning aggressor.
Collapse
Affiliation(s)
- Thomas Bjarnsholt
- Center for Biomedical Microbiology, BioCentrum-DTU Technical University of Denmark, Bldg 301, 2800, Lyngby, Denmark
| | | |
Collapse
|