1
|
Nassar O, Desouky SE, El-Sherbiny GM, Abu-Elghait M. Correlation between phenotypic virulence traits and antibiotic resistance in Pseudomonas aeruginosa clinical isolates. Microb Pathog 2021; 162:105339. [PMID: 34861345 DOI: 10.1016/j.micpath.2021.105339] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2021] [Revised: 11/25/2021] [Accepted: 11/28/2021] [Indexed: 12/21/2022]
Abstract
Pseudomonas aeruginosa is a ubiquitous pathogen capable of infecting virtually all tissues and its one of the standout amongst the most hazardous microorganisms of high morbidity and mortality rates especially in debilitated patients with few successful antibiotic choices available. This pathogen regulating most virulence traits by that so-called quorum sensing (QS), a cell to cell communication system. the present study was intended to phenotypically evaluate the activity of specific virulence traits (including swarming and swimming motility, protease, pyocyanin, and biofilm production) in Pseudomonas aeruginosa clinical isolates and assess the statistical correlation between these traits and antibiotic resistance. One hundred and thirteen bacterial isolates were obtained from different clinical samples and identified as P. aeruginosa, among them, 73.4% have the ability to forming biofilm with different degrees; 59.2% were able to produce pyocyanin pigment while all isolates having the ability to make swarming and swimming motility and able to produce protease enzyme with different degrees. The isolates that produce the higher levels of the virulence traits were identified by both biochemical using Vitek2 automated system and genetically via 16s rRNA gene analysis. The statistical analysis results indicate that a positive significant correlation was found between biofilm formation and other studied virulence traits except for protease (r = 0.584: 0.324, P < 0.05) while a non-significant correlation was found between biofilm formation and protease activity (r = 0.105, P ˃ 0.05). Swimming and swarming motility have a positive significant correlation with other studied virulence traits (r = 0.613: 0.297, P < 0.05) except for protease. Pyocyanin pigment production have a positive significant correlation with other studied virulence traits (r = 0.33: 0.297, P < 0.05) except for protease. on the other hand, negative significant correlations were found between biofilm formation, swimming; and swarming motility, Pyocyanin pigment production, and the susceptibility of antibiotics (r = -0.512: -0.281, P < 0.05). Detection of such correlations in P. aeruginosa is useful for study the behavior of this pathogen and may be provide a new target for the treatment of MDR infections.
Collapse
Affiliation(s)
- Osama Nassar
- Department of Botany and Microbiology, Faculty of Science, Al-Azhar University, 11884, Cairo, Egypt
| | - Said E Desouky
- Department of Botany and Microbiology, Faculty of Science, Al-Azhar University, 11884, Cairo, Egypt
| | - Gamal M El-Sherbiny
- Department of Botany and Microbiology, Faculty of Science, Al-Azhar University, 11884, Cairo, Egypt
| | - Mohammed Abu-Elghait
- Department of Botany and Microbiology, Faculty of Science, Al-Azhar University, 11884, Cairo, Egypt.
| |
Collapse
|
2
|
Bhardwaj S, Bhatia S, Singh S, Franco Jr F. Growing emergence of drug-resistant Pseudomonas aeruginosa and attenuation of its virulence using quorum sensing inhibitors: A critical review. IRANIAN JOURNAL OF BASIC MEDICAL SCIENCES 2021; 24:699-719. [PMID: 34630947 PMCID: PMC8487598 DOI: 10.22038/ijbms.2021.49151.11254] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/30/2020] [Accepted: 11/24/2020] [Indexed: 12/25/2022]
Abstract
A perilous increase in the number of bacterial infections has led to developing throngs of antibiotics for increasing the quality and expectancy of life. Pseudomonas aeruginosa is becoming resistant to all known conventional antimicrobial agents thereby posing a deadly threat to the human population. Nowadays, targeting virulence traits of infectious agents is an alternative approach to antimicrobials that is gaining much popularity to fight antimicrobial resistance. Quorum sensing (QS) involves interspecies communication via a chemical signaling pathway. Under this mechanism, cells work in a concerted manner, communicate with each other with the help of signaling molecules called auto-inducers (AI). The virulence of these strains is driven by genes, whose expression is regulated by AI, which in turn acts as transcriptional activators. Moreover, the problem of antibiotic-resistance in case of infections caused by P. aeruginosa becomes more alarming among immune-compromised patients, where the infectious agents easily take over the cellular machinery of the host while hidden in the QS mediated biofilms. Inhibition of the QS circuit of P. aeruginosa by targeting various signaling pathways such as LasR, RhlR, Pqs, and QScR transcriptional proteins will help in blocking downstream signal transducers which could result in reducing the bacterial virulence. The anti-virulence agent does not pose an immediate selective pressure on growing bacterium and thus reduces the pathogenicity without harming the target species. Here, we review exclusively, the growing emergence of multi-drug resistant (MDR) P. aeruginosa and the critical literature survey of QS inhibitors with their potential application of blocking P. aeruginosa infections.
Collapse
Affiliation(s)
- Snigdha Bhardwaj
- Department of Pharmaceutical Science, SHALOM Institute of Health and Allied Sciences, Sam Higginbottom University of Agriculture, Technology and Sciences (SHUATS), Naini, Prayagraj, India
| | - Sonam Bhatia
- Department of Pharmaceutical Science, SHALOM Institute of Health and Allied Sciences, Sam Higginbottom University of Agriculture, Technology and Sciences (SHUATS), Naini, Prayagraj, India
| | - Shaminder Singh
- Regional Centre for Biotechnology, NCR Biotech Science Cluster, 3rd Milestone, Faridabad-Gurugram Expressway, Faridabad - 121 001, Haryana, India
| | - Francisco Franco Jr
- Department of Chemistry, De La Salle University, Manila, Metro Manila, Philippines
| |
Collapse
|
3
|
Morpholinium-based ionic liquids show antimicrobial activity against clinical isolates of Pseudomonas aeruginosa. Res Microbiol 2021; 172:103817. [PMID: 33741516 DOI: 10.1016/j.resmic.2021.103817] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2020] [Revised: 03/02/2021] [Accepted: 03/04/2021] [Indexed: 11/22/2022]
Abstract
Pseudomonas aeruginosa is a multi-drug resistant (MDR) pathogen. It is classified by WHO as one of the most life-threatening pathogens causing nosocomial infections. Some of its clinical isolates and their subpopulations show high persistence to many antibiotics that are recommended by the European Committee on Antimicrobial Susceptibility Testing (EUCAST). Thus, there is a need for non-traditional classes of antibiotics to fight the increasing threat of MDR P. aeruginosa. Ionic liquids (IL) are one such promising class of novel antibiotics. We selected four strains of P. aeruginosa and studied the growth inhibition and other effects of 12 different ILs. We used the well-characterized P. aeruginosa PAO1 (ATCC 15692) as model strain and compared it to three other isolates from chronic lung infection (LES B58), skin burn infection (UCBPP-PA14) and keratitis infection (39016), respectively. The ILs consisted of either 4,4-didecylmorpholinium [Dec2Mor]+ or 4-decyl-4-ethylmorpholinium [DecEtMor]+ cations combined with different anions. We found that the ILs with 4,4-didecylmorpholinium [Dec2Mor]+ cations most effectively inhibited bacterial growth as well as reduced strain fitness and virulence factor production. Our results indicate that these ILs could be used to treat P. aeruginosa infections.
Collapse
|
4
|
Ghoreishi FS, Roghanian R, Emtiazi G. Inhibition of quorum sensing-controlled virulence factors with natural substances and novel protease, obtained from Halobacillus karajensis. Microb Pathog 2020; 149:104555. [PMID: 33010361 DOI: 10.1016/j.micpath.2020.104555] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2020] [Revised: 09/26/2020] [Accepted: 09/28/2020] [Indexed: 10/23/2022]
Abstract
INTRODUCTION In recent years, a challenge in clinical treatment has developed due to bacterial resistance to antibiotics. One of the new mechanisms against infections is virulence factor inhibition. Many virulence factors are controlled by quorum sensing pathways such as biofilm formation and pyocyanin production. The goal of the present study was to investigate the effect of an obligate halophilic bacterial strain on Pseudomonas aeruginosa and Staphylococcus aureus, due to its halo-tolerant substances and enzymes. METHODS The effect of Halobacillus karajensis on bacterial growth and production of virulence factors was studied in this work. The obligate halophile cells and supernatant fractions were extracted by the methanol/chloroform method and characterized by Fourier Transform Infrared (FTIR) spectroscopy, X-ray diffraction (XRD), Gas Chromatography-Mass Spectrometry (GC-MS), and zymography. The effects of these fractions were studied on biofilm formation in P. aeruginosa and S. aureus as well as on pyocyanin production in P. aeruginosa. The effective protein in the fraction was analyzed by the SDS-PAGE method, and all protein fragments were studied for pyocyanin inhibition. RESULTS The crude supernatant extract, MMS fraction, from H. karajensis was effective for the biofilm reduction in S. aureus (74%) and P. aeruginosa (27%). Two proteases in this fraction, which were recognized by zymography on skim milk, were the probable causes for extracellular polymeric substances (EPS) hydrolysis in the biofilm matrix. Also, halide crystals and branched fatty acids, 12methyl-tetradecanoic acid, in the other fractions decreased the biofilm by 18% in S. aureus. The results showed that a new 25 kD protein, which was obtained from MMS fraction, inhibited pyocyanin production by 60% in P. aeruginosa. The zymogram and bioinformatics studies showed that this protein was a serine alkaline metalloprotease and had an interaction with AHL molecules. CONCLUSION The inhibitory effects of the non-toxic natural substances and proteases on biofilm formation and pyocyanin production, specifically the 25 kD protease, are novel in this study and make them a good candidate for infected wound healing and inhibiting the virulence factors.
Collapse
Affiliation(s)
- Fatemeh S Ghoreishi
- Department of Cell and Molecular Biology & Microbiology, Faculty of Biological Science and Technology, University of Isfahan, Isfahan, Iran
| | - Rasoul Roghanian
- Department of Cell and Molecular Biology & Microbiology, Faculty of Biological Science and Technology, University of Isfahan, Isfahan, Iran.
| | - Giti Emtiazi
- Department of Cell and Molecular Biology & Microbiology, Faculty of Biological Science and Technology, University of Isfahan, Isfahan, Iran
| |
Collapse
|
5
|
Hug JJ, Dastbaz J, Adam S, Revermann O, Koehnke J, Krug D, Müller R. Biosynthesis of Cittilins, Unusual Ribosomally Synthesized and Post-translationally Modified Peptides from Myxococcus xanthus. ACS Chem Biol 2020; 15:2221-2231. [PMID: 32639716 DOI: 10.1021/acschembio.0c00430] [Citation(s) in RCA: 37] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Cittilins are secondary metabolites from myxobacteria comprised of three l-tyrosines and one l-isoleucine forming a bicyclic tetrapeptide scaffold with biaryl and aryl-oxygen-aryl ether bonds. Here we reveal that cittilins belong to the ribosomally synthesized and post-translationally modified peptide (RiPP) family of natural products, for which only the crocagins have been reported from myxobacteria. A 27 amino acid precursor peptide harbors a C-terminal four amino acid core peptide, which is enzymatically modified and finally exported to yield cittilins. The small biosynthetic gene cluster responsible for cittilin biosynthesis also encodes a cytochrome P450 enzyme and a methyltransferase, whereas a gene encoding a prolyl endopeptidase for the cleavage of the precursor peptide is located outside of the cittilin biosynthetic gene cluster. We confirm the roles of the biosynthetic genes responsible for the formation of cittilins using targeted gene inactivation and heterologous expression in Streptomyces ssp. We also report first steps toward the biochemical characterization of the proposed biosynthetic pathway in vitro. An investigation of the cellular uptake properties of cittilin A connected it to a potential biological function as an inhibitor of the prokaryotic carbon storage regulator A (CsrA).
Collapse
Affiliation(s)
- Joachim J. Hug
- Department Microbial Natural Products, Helmholtz-Institute for Pharmaceutical Research Saarland (HIPS), Helmholtz Centre for Infection Research (HZI) and Department of Pharmaceutical Biotechnology, Saarland University, Campus E8.1, 66123 Saarbrücken, Germany
- German Center for Infection Research (DZIF), Partner Site Hannover-Braunschweig, 38124 Braunschweig, Germany
| | - Jan Dastbaz
- Department Microbial Natural Products, Helmholtz-Institute for Pharmaceutical Research Saarland (HIPS), Helmholtz Centre for Infection Research (HZI) and Department of Pharmaceutical Biotechnology, Saarland University, Campus E8.1, 66123 Saarbrücken, Germany
- German Center for Infection Research (DZIF), Partner Site Hannover-Braunschweig, 38124 Braunschweig, Germany
| | - Sebastian Adam
- Department Structural Biology of Biosynthetic Enzymes, Helmholtz-Institute for Pharmaceutical Research Saarland (HIPS), Helmholtz Centre for Infection Research (HZI) and Department of Pharmaceutical Biotechnology, Saarland University, Campus E8.1, 66123 Saarbrücken, Germany
| | - Ole Revermann
- Department Microbial Natural Products, Helmholtz-Institute for Pharmaceutical Research Saarland (HIPS), Helmholtz Centre for Infection Research (HZI) and Department of Pharmaceutical Biotechnology, Saarland University, Campus E8.1, 66123 Saarbrücken, Germany
- German Center for Infection Research (DZIF), Partner Site Hannover-Braunschweig, 38124 Braunschweig, Germany
| | - Jesko Koehnke
- Department Structural Biology of Biosynthetic Enzymes, Helmholtz-Institute for Pharmaceutical Research Saarland (HIPS), Helmholtz Centre for Infection Research (HZI) and Department of Pharmaceutical Biotechnology, Saarland University, Campus E8.1, 66123 Saarbrücken, Germany
| | - Daniel Krug
- Department Microbial Natural Products, Helmholtz-Institute for Pharmaceutical Research Saarland (HIPS), Helmholtz Centre for Infection Research (HZI) and Department of Pharmaceutical Biotechnology, Saarland University, Campus E8.1, 66123 Saarbrücken, Germany
- German Center for Infection Research (DZIF), Partner Site Hannover-Braunschweig, 38124 Braunschweig, Germany
| | - Rolf Müller
- Department Microbial Natural Products, Helmholtz-Institute for Pharmaceutical Research Saarland (HIPS), Helmholtz Centre for Infection Research (HZI) and Department of Pharmaceutical Biotechnology, Saarland University, Campus E8.1, 66123 Saarbrücken, Germany
- German Center for Infection Research (DZIF), Partner Site Hannover-Braunschweig, 38124 Braunschweig, Germany
| |
Collapse
|
6
|
Froes TQ, Baldini RL, Vajda S, Castilho MS. Structure-based Druggability Assessment of Anti-virulence Targets from Pseudomonas aeruginosa. Curr Protein Pept Sci 2020; 20:1189-1203. [PMID: 31038064 DOI: 10.2174/1389203720666190417120758] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2018] [Revised: 02/12/2019] [Accepted: 02/28/2019] [Indexed: 11/22/2022]
Abstract
Antimicrobial Resistance (AMR) represents a serious threat to health and the global economy. However, interest in antibacterial drug development has decreased substantially in recent decades. Meanwhile, anti-virulence drug development has emerged as an attractive alternative to fight AMR. Although several macromolecular targets have been explored for this goal, their druggability is a vital piece of information that has been overlooked. This review explores this subject by showing how structure- based freely available in silico tools, such as PockDrug and FTMap, might be useful for designing novel inhibitors of the pyocyanin biosynthesis pathway and improving the potency/selectivity of compounds that target the Pseudomonas aeruginosa quorum sensing mechanism. The information provided by hotspot analysis, along with binding site features, reveals novel druggable targets (PhzA and PhzS) that remain largely unexplored. However, it also highlights that in silico druggability prediction tools have several limitations that might be overcome in the near future. Meanwhile, anti-virulence drug targets should be assessed by complementary methods, such as the combined use of FTMap/PockDrug, once the consensus druggability classification reduces the risk of wasting resources on undruggable proteins.
Collapse
Affiliation(s)
- Thamires Q Froes
- Programa de Pos-Graduacao em Biotecnologia da Universidade Estadual de Feira de Santana, Feira de Santana, BA, Brazil.,aculdade de Farmácia da Universidade Federal da Bahia, Bahia, Salvador, BA, Brazil
| | - Regina L Baldini
- Departamento de Bioquimica, Instituto de Quimica, Universidade de Sao Paulo. Sao Paulo, SP, Brazil
| | - Sandor Vajda
- College of Engineering, Boston University, Boston, MA, United States
| | - Marcelo S Castilho
- Programa de Pos-Graduacao em Biotecnologia da Universidade Estadual de Feira de Santana, Feira de Santana, BA, Brazil.,aculdade de Farmácia da Universidade Federal da Bahia, Bahia, Salvador, BA, Brazil.,College of Engineering, Boston University, Boston, MA, United States
| |
Collapse
|
7
|
Design, synthesis, and evaluation of compounds capable of reducing Pseudomonas aeruginosa virulence. Eur J Med Chem 2019; 185:111800. [PMID: 31706639 DOI: 10.1016/j.ejmech.2019.111800] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2019] [Revised: 10/16/2019] [Accepted: 10/17/2019] [Indexed: 12/26/2022]
Abstract
Anti-virulence approaches in the treatment of Pseudomonas aeruginosa (PA)-induced infections have shown clinical potential in multiple in vitro and in vivo studies. However, development of these compounds is limited by several factors, including the lack of molecules capable of penetrating the membrane of gram-negative organisms. Here, we report the identification of novel structurally diverse compounds that inhibit PqsR and LasR-based signaling and diminish virulence factor production and biofilm growth in two clinically relevant strains of P. aeruginosa. It is the first report where potential anti-virulent agents were evaluated for inhibition of several virulence factors of PA. Finally, co-treatment with these inhibitors significantly reduced the production of virulence factors induced by the presence of sub-inhibitory levels of ciprofloxacin. Further, we have analyzed the drug-likeness profile of designed compounds using quantitative estimates of drug-likeness (QED) and confirmed their potential as hit molecules for further development.
Collapse
|
8
|
Khan F, Lee JW, Manivasagan P, Pham DTN, Oh J, Kim YM. Synthesis and characterization of chitosan oligosaccharide-capped gold nanoparticles as an effective antibiofilm drug against the Pseudomonas aeruginosa PAO1. Microb Pathog 2019; 135:103623. [PMID: 31325574 DOI: 10.1016/j.micpath.2019.103623] [Citation(s) in RCA: 43] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2019] [Revised: 06/14/2019] [Accepted: 07/16/2019] [Indexed: 01/09/2023]
Abstract
The infection caused by Pseudomonas aeruginosa is a serious concern in human health. The bacterium is an opportunistic pathogen which has been reported to cause nosocomial and chronic infections through biofilm formation and synthesis of several toxins and virulence factors. Furthermore, the formation of biofilm by P. aeruginosa is known as one of the resistance mechanisms against conventional antibiotics. Natural compounds from marine resources have become one of the simple, cost-effective, biocompatible and non-toxicity for treating P. aeruginosa biofilm-related infections. Furthermore, hybrid formulation with nanomaterials such as nanoparticles becomes an effective alternative strategy to minimize the drug toxicity problem and cytotoxicity properties. For this reason, the present study has employed chitosan oligosaccharide for the synthesis of chitosan oligosaccharide-capped gold nanoparticles (COS-AuNPs). The synthesized COS-AuNPs were then characterized by using UV-Visible spectroscopy, Dynamic light scattering (DLS), Fourier transform infrared spectroscopy (FTIR), Field emission transmission electron microscopy (FE-TEM), and Energy dispersive X-ray diffraction (EDX). The synthesized COS-AuNPs were applied for inhibiting P. aeruginosa biofilm formation. Results have shown that COS-AuNPs exhibited inhibition to biofilm as well as eradication to pre-existing mature biofilm. Simultaneously, COS-AuNPs were also able to reduce bacterial hemolysis and different virulence factors produced by P. aeruginosa. Overall, the present study concluded that the hybrid nanoformulation such as COS-AuNPs could act as a potential agent to exhibit inhibitory properties against the P. aeruginosa pathogenesis arisen from biofilm formation.
Collapse
Affiliation(s)
- Fazlurrahman Khan
- Marine-Integrated Bionics Research Center, Pukyong National University, Busan, 48513, Republic of Korea
| | - Jang-Won Lee
- Department of Food Science and Technology, Pukyong National University, Busan, 48513, Republic of Korea
| | - Panchanathan Manivasagan
- Marine-Integrated Bionics Research Center, Pukyong National University, Busan, 48513, Republic of Korea
| | - Dung Thuy Nguyen Pham
- Department of Food Science and Technology, Pukyong National University, Busan, 48513, Republic of Korea
| | - Junghwan Oh
- Marine-Integrated Bionics Research Center, Pukyong National University, Busan, 48513, Republic of Korea; Department of Biomedical Engineering, Pukyong National University, Busan, 48513, Republic of Korea
| | - Young-Mog Kim
- Marine-Integrated Bionics Research Center, Pukyong National University, Busan, 48513, Republic of Korea; Department of Food Science and Technology, Pukyong National University, Busan, 48513, Republic of Korea.
| |
Collapse
|
9
|
Lahiri D, Dash S, Dutta R, Nag M. Elucidating the effect of anti-biofilm activity of bioactive compounds extracted from plants. J Biosci 2019; 44:52. [PMID: 31180065] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Affiliation(s)
- Dibyajit Lahiri
- Department of Biotechnology, University of Engineering and Management, Kolkata, India
| | | | | | | |
Collapse
|
10
|
Erfanimanesh S, Eslami G, Taherpour A, Hashemi A. Capsaicin inhibitory effects on Vibrio cholerae toxin genes expression. AVICENNA JOURNAL OF PHYTOMEDICINE 2019; 9:187-194. [PMID: 31143687 PMCID: PMC6526041] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
OBJECTIVE Cholera is an acute secretory diarrhea caused by the Gram-negative bacterium, Vibrio cholerae mostly through production of cholera toxin (CT) and zonula occludens toxin (Zot). Isolates of V. cholerae have acquired resistance elements during the last decade. One of the most promising ways to treat resistant strains is to use antivirulence agents instead of killing the causative agent with conventional antibiotics. In this study, we examined whether different concentrations of capsaicin - the pungent fraction of red chili- can act as an antivirulence agent and inhibit V. cholerae toxin production. MATERIALS AND METHODS Two standard strains namely, V. cholerae ATCC 14035 and V. cholerae PTCC 1611 were used in this study. Minimum Inhibitory Concentration (MIC) of capsaicin was determined by broth microdilution method. Based on MIC results, the bacteria were cultured in the presence of sub-MIC concentrations of capsaicin and a negative control without capsaicin. Real-time PCR (RT-PCR) was carried out to determine the expression level of V. cholerae toxin genes at each concentration. RESULTS MIC test showed that 200 mg/mL of capsaicin in 2% dimethyl sulfoxide (DMSO) could inhibit the growth of the two standard strains of V. cholerae. The expression of V. cholerae toxin genes was significantly reduced following treatment with sub-MIC concentrations of capsaicin as assessed by RT-PCR. CONCLUSION Capsaicin showed great inhibitory effect against cholera toxin and reduced Zot production in the tested strains of V. cholerae. The results showed promising insights into antivirulence effects of capsaicin.
Collapse
Affiliation(s)
- Soroor Erfanimanesh
- Infectious Diseases and Tropical Medicine Research Center, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Gita Eslami
- Infectious Diseases and Tropical Medicine Research Center, Shahid Beheshti University of Medical Sciences, Tehran, Iran,Corresponding Author: Tel: +98 21 23872556, Fax: +98-2122439964,
| | - Arezou Taherpour
- Department of Microbiology, Kurdistan University of Medical Sciences, Sanandaj, Iran
| | - Ali Hashemi
- Department of Microbiology, School of Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| |
Collapse
|
11
|
Vasquez JK, Tal-Gan Y, Cornilescu G, Tyler KA, Blackwell HE. Simplified AIP-II Peptidomimetics Are Potent Inhibitors of Staphylococcus aureus AgrC Quorum Sensing Receptors. Chembiochem 2017; 18:413-423. [PMID: 28006082 DOI: 10.1002/cbic.201600516] [Citation(s) in RCA: 36] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2016] [Indexed: 01/13/2023]
Abstract
The bacterial pathogen Staphylococcus aureus controls many aspects of virulence by using the accessory gene regulator (agr) quorum sensing (QS) system. The agr system is activated by a macrocyclic peptide signal known as an autoinducing peptide (AIP). We sought to develop structurally simplified mimetics of AIPs for use as chemical tools to study QS in S. aureus. Herein, we report new peptidomimetic AgrC receptor inhibitors based on a tail-truncated AIP-II peptide that have almost analogous inhibitory activities to the parent peptide. Structural comparison of one of these peptidomimetics to the parent peptide and a highly potent, all-peptide-derived, S. aureus agr inhibitor (AIP-III D4A) revealed a conserved hydrophobic motif and overall amphipathic nature. Our results suggest that the AIP scaffold is amenable to structural mimicry and minimization for the development of synthetic agr inhibitors.
Collapse
Affiliation(s)
- Joseph K Vasquez
- Department of Chemistry, University of Wisconsin, 1101 University Avenue, Madison, WI, 53706, USA
| | - Yftah Tal-Gan
- Department of Chemistry, University of Wisconsin, 1101 University Avenue, Madison, WI, 53706, USA.,Present address: Department of Chemistry, University of Nevada, 1664 N. Virginia Street, Reno, NV, 89557, USA
| | - Gabriel Cornilescu
- National Magnetic Resonance Facility at Madison, University of Wisconsin, 433 Babcock Drive, Madison, WI, 53706, USA
| | - Kimberly A Tyler
- Department of Chemistry, University of Wisconsin, 1101 University Avenue, Madison, WI, 53706, USA
| | - Helen E Blackwell
- Department of Chemistry, University of Wisconsin, 1101 University Avenue, Madison, WI, 53706, USA
| |
Collapse
|
12
|
Cellular Effects of Pyocyanin, a Secreted Virulence Factor of Pseudomonas aeruginosa. Toxins (Basel) 2016; 8:toxins8080236. [PMID: 27517959 PMCID: PMC4999852 DOI: 10.3390/toxins8080236] [Citation(s) in RCA: 244] [Impact Index Per Article: 30.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2016] [Revised: 08/03/2016] [Accepted: 08/03/2016] [Indexed: 11/17/2022] Open
Abstract
Pyocyanin has recently emerged as an important virulence factor produced by Pseudomonas aeruginosa. The redox-active tricyclic zwitterion has been shown to have a number of potential effects on various organ systems in vitro, including the respiratory, cardiovascular, urological, and central nervous systems. It has been shown that a large number of the effects to these systems are via the formation of reactive oxygen species. The limitations of studies are, to date, focused on the localized effect of the release of pyocyanin (PCN). It has been postulated that, given its chemical properties, PCN is able to readily cross biological membranes, however studies have yet to be undertaken to evaluate this effect. This review highlights the possible manifestations of PCN exposure; however, most studies to date are in vitro. Further high quality in vivo studies are needed to fully assess the physiological manifestations of PCN exposure on the various body systems.
Collapse
|