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Rémy B, Plener L, Decloquement P, Armstrong N, Elias M, Daudé D, Chabrière É. Lactonase Specificity Is Key to Quorum Quenching in Pseudomonas aeruginosa. Front Microbiol 2020; 11:762. [PMID: 32390993 PMCID: PMC7193897 DOI: 10.3389/fmicb.2020.00762] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2020] [Accepted: 03/30/2020] [Indexed: 12/31/2022] Open
Abstract
The human opportunistic pathogen Pseudomonas aeruginosa orchestrates the expression of many genes in a cell density-dependent manner by using quorum sensing (QS). Two acyl-homoserine lactones (AHLs) are involved in QS circuits and contribute to the regulation of virulence factors production, biofilm formation, and antimicrobial sensitivity. Disrupting QS, a strategy referred to as quorum quenching (QQ) can be achieved using exogenous AHL-degrading lactonases. However, the importance of enzyme specificity on quenching efficacy has been poorly investigated. Here, we used two lactonases both targeting the signal molecules N-(3-oxododecanoyl)-L-homoserine lactone (3-oxo-C12 HSL) and butyryl-homoserine lactone (C4 HSL) albeit with different efficacies on C4 HSL. Interestingly, both lactonases similarly decreased AHL concentrations and comparably impacted the expression of AHL-based QS genes. However, strong variations were observed in Pseudomonas Quinolone Signal (PQS) regulation depending on the lactonase used. Both lactonases were also found to decrease virulence factors production and biofilm formation in vitro, albeit with different efficiencies. Unexpectedly, only the lactonase with lower efficacy on C4 HSL was able to inhibit P. aeruginosa pathogenicity in vivo in an amoeba infection model. Similarly, proteomic analysis revealed large variations in protein levels involved in antibiotic resistance, biofilm formation, virulence and diverse cellular mechanisms depending on the chosen lactonase. This global analysis provides evidences that QQ enzyme specificity has a significant impact on the modulation of QS-associated behavior in P. aeruginosa PA14.
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Affiliation(s)
- Benjamin Rémy
- Aix Marseille University, Institut de Recherche pour le Développement, Assistance Publique - Hôpitaux de Marseille, Microbes Evolution Phylogeny and Infections, Institut Hospitalo-Universitaire-Méditerranée Infection, Marseille, France.,Gene&GreenTK, Marseille, France
| | | | - Philippe Decloquement
- Aix Marseille University, Institut de Recherche pour le Développement, Assistance Publique - Hôpitaux de Marseille, Microbes Evolution Phylogeny and Infections, Institut Hospitalo-Universitaire-Méditerranée Infection, Marseille, France
| | - Nicholas Armstrong
- Aix Marseille University, Institut de Recherche pour le Développement, Assistance Publique - Hôpitaux de Marseille, Microbes Evolution Phylogeny and Infections, Institut Hospitalo-Universitaire-Méditerranée Infection, Marseille, France
| | - Mikael Elias
- Department of Biochemistry, Molecular Biology and Biophysics - BioTechnology Institute, University of Minnesota, St. Paul, MN, United States
| | | | - Éric Chabrière
- Aix Marseille University, Institut de Recherche pour le Développement, Assistance Publique - Hôpitaux de Marseille, Microbes Evolution Phylogeny and Infections, Institut Hospitalo-Universitaire-Méditerranée Infection, Marseille, France
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Bashir A, Tian T, Yu X, Meng C, Ali M, Li L. Pyoverdine-Mediated Killing of Caenorhabditis elegans by Pseudomonas syringae MB03 and the Role of Iron in Its Pathogenicity. Int J Mol Sci 2020; 21:ijms21062198. [PMID: 32235814 PMCID: PMC7139650 DOI: 10.3390/ijms21062198] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2020] [Revised: 03/19/2020] [Accepted: 03/20/2020] [Indexed: 12/28/2022] Open
Abstract
The pathogenicity of the common phytopathogenic bacterium Pseudomonas syringae toward Caenorhabditis elegans has been recently demonstrated. However, the major virulence factors involved in this interaction remain unknown. In this study, we investigated the nematocidal activity of P. syringae against C. elegans under iron-sufficient/limited conditions, primarily focusing on the role of the ferric chelator pyoverdine in a P. syringae–C. elegans liquid-based pathogenicity model. Prediction-based analysis of pyoverdine-encoding genes in the genome of the wild-type P. syringae strain MB03 revealed that the genes are located in one large cluster. Two non-ribosomal peptide synthetase genes (pvdD and pvdJ) were disrupted via a Rec/TE recombination system, resulting in mutant strains with abrogated pyoverdine production and attenuated virulence against C. elegans. When used alone, pure pyoverdine also showed nematocidal activity. The role of iron used alone or with pyoverdine was further investigated in mutant and MB03-based bioassays. The results indicated that pyoverdine in P. syringae MB03 is a robust virulence factor that promotes the killing of C. elegans. We speculate that pyoverdine functions as a virulence determinant by capturing environmentally available iron for host bacterial cells, by limiting its availability for C. elegans worms, and by regulating and/or activating other intracellular virulence factors that ultimately kills C. elegans worms.
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Affiliation(s)
- Anum Bashir
- State Key Laboratory of Agricultural Microbiology, Huazhong Agricultural University, Wuhan 430070, China; (A.B.); (T.T.); (X.Y.); (M.A.)
| | - Tian Tian
- State Key Laboratory of Agricultural Microbiology, Huazhong Agricultural University, Wuhan 430070, China; (A.B.); (T.T.); (X.Y.); (M.A.)
| | - Xun Yu
- State Key Laboratory of Agricultural Microbiology, Huazhong Agricultural University, Wuhan 430070, China; (A.B.); (T.T.); (X.Y.); (M.A.)
| | - Cui Meng
- State Key Laboratory of Agricultural Microbiology, Huazhong Agricultural University, Wuhan 430070, China; (A.B.); (T.T.); (X.Y.); (M.A.)
| | - Muhammad Ali
- State Key Laboratory of Agricultural Microbiology, Huazhong Agricultural University, Wuhan 430070, China; (A.B.); (T.T.); (X.Y.); (M.A.)
- Department of Biotechnology, COMSATS University Islamabad, Abbottabad Campus, Abbottabad 22060, Pakistan
| | - Lin Li
- State Key Laboratory of Agricultural Microbiology, Huazhong Agricultural University, Wuhan 430070, China; (A.B.); (T.T.); (X.Y.); (M.A.)
- Correspondence: ; Tel.: +86-27-8728-6952
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Sepúlveda-Crespo D, Reguera RM, Rojo-Vázquez F, Balaña-Fouce R, Martínez-Valladares M. Drug discovery technologies: Caenorhabditis elegans as a model for anthelmintic therapeutics. Med Res Rev 2020; 40:1715-1753. [PMID: 32166776 DOI: 10.1002/med.21668] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2019] [Revised: 12/10/2019] [Accepted: 02/26/2020] [Indexed: 12/16/2022]
Abstract
Helminthiasis is one of the gravest problems worldwide. There is a growing concern on less available anthelmintics and the emergence of resistance creating a major threat to human and livestock health resources. Novel and broad-spectrum anthelmintics are urgently needed. The free-living nematode Caenorhabditis elegans could address this issue through automated high-throughput technologies for the screening of large chemical libraries. This review discusses the strong advantages and limitations for using C elegans as a screening method for anthelmintic drug discovery. C elegans is the best model available for the validation of novel effective drugs in treating most, if not all, helminth infections, and for the elucidation the mode of action of anthelmintic candidates. This review also focuses on available technologies in the discovery of anthelmintics published over the last 15 years with particular attention to high-throughput technologies over conventional screens. On the other hand, this review highlights how combinatorial and nanomedicine strategies could prolong the use of anthelmintics and control resistance problems.
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Affiliation(s)
- Daniel Sepúlveda-Crespo
- Departamento de Ciencias Biomédicas, Facultad de Veterinaria, Universidad de León, León, Spain
| | - Rosa M Reguera
- Departamento de Ciencias Biomédicas, Facultad de Veterinaria, Universidad de León, León, Spain
| | - Francisco Rojo-Vázquez
- Instituto de Ganadería de Montaña (CSIC-Universidad de León), León, Spain.,Departamento de Sanidad Animal, Facultad de Veterinaria, Universidad de León, León, Spain
| | - Rafael Balaña-Fouce
- Departamento de Ciencias Biomédicas, Facultad de Veterinaria, Universidad de León, León, Spain
| | - María Martínez-Valladares
- Instituto de Ganadería de Montaña (CSIC-Universidad de León), León, Spain.,Departamento de Sanidad Animal, Facultad de Veterinaria, Universidad de León, León, Spain
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Sánchez-Diener I, Zamorano L, Peña C, Ocampo-Sosa A, Cabot G, Gómez-Zorrilla S, Almirante B, Aguilar M, Granados A, Calbo E, Rodriguez-Baño J, Rodríguez-López F, Tubau F, Martínez-Martínez L, Navas A, Oliver A. Weighting the impact of virulence on the outcome of Pseudomonas aeruginosa bloodstream infections. Clin Microbiol Infect 2020; 26:351-357. [DOI: 10.1016/j.cmi.2019.06.034] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2019] [Revised: 06/25/2019] [Accepted: 06/27/2019] [Indexed: 12/18/2022]
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Sonnabend MS, Klein K, Beier S, Angelov A, Kluj R, Mayer C, Groß C, Hofmeister K, Beuttner A, Willmann M, Peter S, Oberhettinger P, Schmidt A, Autenrieth IB, Schütz M, Bohn E. Identification of Drug Resistance Determinants in a Clinical Isolate of Pseudomonas aeruginosa by High-Density Transposon Mutagenesis. Antimicrob Agents Chemother 2020; 64:e01771-19. [PMID: 31818817 PMCID: PMC7038268 DOI: 10.1128/aac.01771-19] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2019] [Accepted: 11/25/2019] [Indexed: 01/02/2023] Open
Abstract
With the aim to identify potential new targets to restore antimicrobial susceptibility of multidrug-resistant (MDR) Pseudomonas aeruginosa isolates, we generated a high-density transposon (Tn) insertion mutant library in an MDR P. aeruginosa bloodstream isolate (isolate ID40). The depletion of Tn insertion mutants upon exposure to cefepime or meropenem was measured in order to determine the common resistome for these clinically important antipseudomonal β-lactam antibiotics. The approach was validated by clean deletions of genes involved in peptidoglycan synthesis/recycling, such as the genes for the lytic transglycosylase MltG, the murein (Mur) endopeptidase MepM1, the MurNAc/GlcNAc kinase AmgK, and the uncharacterized protein YgfB, all of which were identified in our screen as playing a decisive role in survival after treatment with cefepime or meropenem. We found that the antibiotic resistance of P. aeruginosa can be overcome by targeting usually nonessential genes that turn essential in the presence of therapeutic concentrations of antibiotics. For all validated genes, we demonstrated that their deletion leads to the reduction of ampC expression, resulting in a significant decrease in β-lactamase activity, and consequently, these mutants partly or completely lost resistance against cephalosporins, carbapenems, and acylaminopenicillins. In summary, the determined resistome may comprise promising targets for the development of drugs that may be used to restore sensitivity to existing antibiotics, specifically in MDR strains of P. aeruginosa.
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Affiliation(s)
- Michael S Sonnabend
- Interfakultäres Institut für Mikrobiologie und Infektionsmedizin Tübingen (IMIT), Institut für Medizinische Mikrobiologie und Hygiene, Universitätsklinikum Tübingen, Tübingen, Germany
- NGS Competence Center Tübingen (NCCT), Institut für Medizinische Mikrobiologie und Hygiene, Universitätsklinikum Tübingen, Tübingen, Germany
| | - Kristina Klein
- Interfakultäres Institut für Mikrobiologie und Infektionsmedizin Tübingen (IMIT), Institut für Medizinische Mikrobiologie und Hygiene, Universitätsklinikum Tübingen, Tübingen, Germany
| | - Sina Beier
- Center for Bioinformatics (ZBIT), Universität Tübingen, Tübingen, Germany
| | - Angel Angelov
- Interfakultäres Institut für Mikrobiologie und Infektionsmedizin Tübingen (IMIT), Institut für Medizinische Mikrobiologie und Hygiene, Universitätsklinikum Tübingen, Tübingen, Germany
- NGS Competence Center Tübingen (NCCT), Institut für Medizinische Mikrobiologie und Hygiene, Universitätsklinikum Tübingen, Tübingen, Germany
| | - Robert Kluj
- Interfakultäres Institut für Mikrobiologie und Infektionsmedizin Tübingen (IMIT), Department of Biology, Microbiology & Biotechnology, Universität Tübingen, Tübingen, Germany
| | - Christoph Mayer
- Interfakultäres Institut für Mikrobiologie und Infektionsmedizin Tübingen (IMIT), Department of Biology, Microbiology & Biotechnology, Universität Tübingen, Tübingen, Germany
| | - Caspar Groß
- Institut für Medizinische Genetik und Angewandte Genomik, Universitätsklinikum Tübingen, Tübingen, Germany
| | - Kathrin Hofmeister
- Interfakultäres Institut für Mikrobiologie und Infektionsmedizin Tübingen (IMIT), Institut für Medizinische Mikrobiologie und Hygiene, Universitätsklinikum Tübingen, Tübingen, Germany
| | - Antonia Beuttner
- Interfakultäres Institut für Mikrobiologie und Infektionsmedizin Tübingen (IMIT), Institut für Medizinische Mikrobiologie und Hygiene, Universitätsklinikum Tübingen, Tübingen, Germany
| | - Matthias Willmann
- Interfakultäres Institut für Mikrobiologie und Infektionsmedizin Tübingen (IMIT), Institut für Medizinische Mikrobiologie und Hygiene, Universitätsklinikum Tübingen, Tübingen, Germany
- NGS Competence Center Tübingen (NCCT), Institut für Medizinische Mikrobiologie und Hygiene, Universitätsklinikum Tübingen, Tübingen, Germany
| | - Silke Peter
- Interfakultäres Institut für Mikrobiologie und Infektionsmedizin Tübingen (IMIT), Institut für Medizinische Mikrobiologie und Hygiene, Universitätsklinikum Tübingen, Tübingen, Germany
- NGS Competence Center Tübingen (NCCT), Institut für Medizinische Mikrobiologie und Hygiene, Universitätsklinikum Tübingen, Tübingen, Germany
| | - Philipp Oberhettinger
- Interfakultäres Institut für Mikrobiologie und Infektionsmedizin Tübingen (IMIT), Institut für Medizinische Mikrobiologie und Hygiene, Universitätsklinikum Tübingen, Tübingen, Germany
| | - Annika Schmidt
- Interfakultäres Institut für Mikrobiologie und Infektionsmedizin Tübingen (IMIT), Institut für Medizinische Mikrobiologie und Hygiene, Universitätsklinikum Tübingen, Tübingen, Germany
| | - Ingo B Autenrieth
- Interfakultäres Institut für Mikrobiologie und Infektionsmedizin Tübingen (IMIT), Institut für Medizinische Mikrobiologie und Hygiene, Universitätsklinikum Tübingen, Tübingen, Germany
- NGS Competence Center Tübingen (NCCT), Institut für Medizinische Mikrobiologie und Hygiene, Universitätsklinikum Tübingen, Tübingen, Germany
| | - Monika Schütz
- Interfakultäres Institut für Mikrobiologie und Infektionsmedizin Tübingen (IMIT), Institut für Medizinische Mikrobiologie und Hygiene, Universitätsklinikum Tübingen, Tübingen, Germany
| | - Erwin Bohn
- Interfakultäres Institut für Mikrobiologie und Infektionsmedizin Tübingen (IMIT), Institut für Medizinische Mikrobiologie und Hygiene, Universitätsklinikum Tübingen, Tübingen, Germany
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56
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Scott E, Holden-Dye L, O'Connor V, Wand ME. Intra Strain Variation of the Effects of Gram-Negative ESKAPE Pathogens on Intestinal Colonization, Host Viability, and Host Response in the Model Organism Caenorhabditis elegans. Front Microbiol 2020; 10:3113. [PMID: 32038555 PMCID: PMC6985274 DOI: 10.3389/fmicb.2019.03113] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2019] [Accepted: 12/24/2019] [Indexed: 01/21/2023] Open
Abstract
In its native environment of rotting vegetation, the soil nematode Caenorhabditis elegans encounters a range of bacteria. This includes species from the ESKAPE group of pathogens that pose a clinical problem in acquired hospital infections. Here, we investigated three Gram-negative members of the ESKAPE group, Pseudomonas aeruginosa, Klebsiella pneumoniae, and Acinetobacter baumannii. Pathogenicity profiles as measured by time to kill adult C. elegans showed that P. aeruginosa was the most pathogenic, followed by K. pneumoniae, while C. elegans cultured on A. baumannii exhibited the same survival as those on the standard laboratory food source for C. elegans, Escherichia coli OP50. The pathogenicity was paralleled by a reduction in time that C. elegans resided on the bacterial lawn with the most pathogenic strains triggering an increase in the frequency of food-leaving. Previous reports indicate that gut colonization is a feature of pathogenicity, but we found that the most pathogenic strains were not associated with the highest level of colonization. Indeed, clearance of P. aeruginosa strains from the C. elegans gut was independent of bacterial pathogenicity. We show that this clearance is regulated by neuromodulation as C. elegans mutants in unc-31 and egl-3 have enhanced clearance of P. aeruginosa. Intriguingly this is also not linked to their pathogenicity. It is likely that there is a dynamic balance occurring in the C. elegans intestinal environment between maintaining a healthy, beneficial microbiota and removal of pathogenic bacteria.
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Affiliation(s)
- Euan Scott
- School of Biological Sciences, University of Southampton, Southampton, United Kingdom
| | - Lindy Holden-Dye
- School of Biological Sciences, University of Southampton, Southampton, United Kingdom
| | - Vincent O'Connor
- School of Biological Sciences, University of Southampton, Southampton, United Kingdom
| | - Matthew E Wand
- National Infection Service, Public Health England, Salisbury, United Kingdom
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57
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Vasquez-Rifo A, Veksler-Lublinsky I, Cheng Z, Ausubel FM, Ambros V. The Pseudomonas aeruginosa accessory genome elements influence virulence towards Caenorhabditis elegans. Genome Biol 2019; 20:270. [PMID: 31823826 PMCID: PMC6902481 DOI: 10.1186/s13059-019-1890-1] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2019] [Accepted: 11/15/2019] [Indexed: 02/06/2023] Open
Abstract
BACKGROUND Multicellular animals and bacteria frequently engage in predator-prey and host-pathogen interactions, such as the well-studied relationship between Pseudomonas aeruginosa and the nematode Caenorhabditis elegans. This study investigates the genomic and genetic basis of bacterial-driven variability in P. aeruginosa virulence towards C. elegans to provide evolutionary insights into host-pathogen relationships. RESULTS Natural isolates of P. aeruginosa that exhibit diverse genomes display a broad range of virulence towards C. elegans. Using gene association and genetic analysis, we identify accessory genome elements that correlate with virulence, including both known and novel virulence determinants. Among the novel genes, we find a viral-like mobile element, the teg block, that impairs virulence and whose acquisition is restricted by CRISPR-Cas systems. Further genetic and genomic evidence suggests that spacer-targeted elements preferentially associate with lower virulence while the presence of CRISPR-Cas associates with higher virulence. CONCLUSIONS Our analysis demonstrates substantial strain variation in P. aeruginosa virulence, mediated by specific accessory genome elements that promote increased or decreased virulence. We exemplify that viral-like accessory genome elements that decrease virulence can be restricted by bacterial CRISPR-Cas immune defense systems, and suggest a positive, albeit indirect, role for host CRISPR-Cas systems in virulence maintenance.
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Affiliation(s)
- Alejandro Vasquez-Rifo
- Program in Molecular Medicine, University of Massachusetts Medical School, Worcester, MA, 01605, USA.
| | - Isana Veksler-Lublinsky
- Department of Software and Information Systems Engineering, Ben-Gurion University of the Negev, Beer-Sheva, Israel.
| | - Zhenyu Cheng
- Department of Microbiology & Immunology, Dalhousie University, Halifax, Nova Scotia, Canada
| | - Frederick M Ausubel
- Department of Molecular Biology, Massachusetts General Hospital, Boston, MA, 02114, USA
- Department of Genetics, Harvard Medical School, Boston, MA, 02115, USA
| | - Victor Ambros
- Program in Molecular Medicine, University of Massachusetts Medical School, Worcester, MA, 01605, USA
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Qian Z, Hui P, Han L, Ling-Zhi Y, Bo-Shun Z, Jie Z, Wan-Li G, Nan W, Shi-Jin J, Zhi-Jing X. Serotypes and virulence genes of Pseudomonas aeruginosa isolated from mink and its pathogenicity in mink. Microb Pathog 2019; 139:103904. [PMID: 31801681 DOI: 10.1016/j.micpath.2019.103904] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2019] [Revised: 11/26/2019] [Accepted: 11/28/2019] [Indexed: 10/25/2022]
Abstract
In this study, 20 P. aeruginosa strains were isolated from 112 farmed mink exhibiting hemorrhagic pneumonia in mideastern Shandong province, China. Serotype G (18/20) was the dominant serotype among the isolates with prevalence in mink, followed by serotype B (1/20), serotype C (1/20). The 9 virulence-associated genes of P. aeruginosa were tested using PCR. The prevalence of the virulence genes for the isolates were algD 95% (19/20), plcH 85% (17/20), exoY 80% (16/20), aprA 75% (15/20), lasB 70% (14/20), exoS 65% (13/20), exoT 60% (12/20) and toxA 60% (12/20), respectively. The 20 isolates were negative for exoU gene. The isolates exhibited multidrug resistance and cross resistance, using antimicrobial disc susceptibility assays. The animal experiments demonstrated that LD50% of the P.aeruginosa-CS-2 in the intratracheally challenged mink was 2.2 × 107.0 CFU, and 6.8 × 104.0 CFU in the intraperitoneally challenged mink. It implied that both the inoculation doses and the routes of inoculation could have influences on the pathogenicity of P. aeruginosa in mink. Therefore, the evolutionary and epidemiological surveillance of P. aeruginosa in mink should be further strengthened for public health.
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Affiliation(s)
- Zhu Qian
- Shandong Provincial Key Laboratory of Animal Biotechnology and Disease Control and Prevention, Shandong Agricultural University, Taian City, Shandong Province, 271018, China; College of Veterinary Medicine, Shandong Agricultural University, Taian City, Shandong Province, 271018, China; Shandong Provincial Engineering Technology Research Center of Animal Disease Control and Prevention, Shandong Agricultural University, Taian City, Shandong Province, 271018, China
| | - Peng Hui
- Shandong Provincial Key Laboratory of Animal Biotechnology and Disease Control and Prevention, Shandong Agricultural University, Taian City, Shandong Province, 271018, China; College of Veterinary Medicine, Shandong Agricultural University, Taian City, Shandong Province, 271018, China; Shandong Provincial Engineering Technology Research Center of Animal Disease Control and Prevention, Shandong Agricultural University, Taian City, Shandong Province, 271018, China
| | - Li Han
- Shandong Provincial Key Laboratory of Animal Biotechnology and Disease Control and Prevention, Shandong Agricultural University, Taian City, Shandong Province, 271018, China; College of Veterinary Medicine, Shandong Agricultural University, Taian City, Shandong Province, 271018, China; Shandong Provincial Engineering Technology Research Center of Animal Disease Control and Prevention, Shandong Agricultural University, Taian City, Shandong Province, 271018, China
| | - Yang Ling-Zhi
- Shandong Provincial Engineering Technology Research Center of Animal Disease Control and Prevention, Shandong Agricultural University, Taian City, Shandong Province, 271018, China; Shandong Binzhou Wohua Biotech Co.,LTD, Binzhou City, Shandong Province, 256600, China
| | - Zhang Bo-Shun
- Shandong Provincial Key Laboratory of Animal Biotechnology and Disease Control and Prevention, Shandong Agricultural University, Taian City, Shandong Province, 271018, China; College of Veterinary Medicine, Shandong Agricultural University, Taian City, Shandong Province, 271018, China; Shandong Provincial Engineering Technology Research Center of Animal Disease Control and Prevention, Shandong Agricultural University, Taian City, Shandong Province, 271018, China
| | - Zhu Jie
- Shandong Provincial Engineering Technology Research Center of Animal Disease Control and Prevention, Shandong Agricultural University, Taian City, Shandong Province, 271018, China; Shandong Binzhou Wohua Biotech Co.,LTD, Binzhou City, Shandong Province, 256600, China
| | - Guo Wan-Li
- Shandong Provincial Key Laboratory of Animal Biotechnology and Disease Control and Prevention, Shandong Agricultural University, Taian City, Shandong Province, 271018, China; College of Veterinary Medicine, Shandong Agricultural University, Taian City, Shandong Province, 271018, China; Shandong Provincial Engineering Technology Research Center of Animal Disease Control and Prevention, Shandong Agricultural University, Taian City, Shandong Province, 271018, China
| | - Wang Nan
- Shandong Provincial Engineering Technology Research Center of Animal Disease Control and Prevention, Shandong Agricultural University, Taian City, Shandong Province, 271018, China; Shandong Binzhou Wohua Biotech Co.,LTD, Binzhou City, Shandong Province, 256600, China
| | - Jiang Shi-Jin
- Shandong Provincial Key Laboratory of Animal Biotechnology and Disease Control and Prevention, Shandong Agricultural University, Taian City, Shandong Province, 271018, China; College of Veterinary Medicine, Shandong Agricultural University, Taian City, Shandong Province, 271018, China; Shandong Provincial Engineering Technology Research Center of Animal Disease Control and Prevention, Shandong Agricultural University, Taian City, Shandong Province, 271018, China
| | - Xie Zhi-Jing
- Shandong Provincial Key Laboratory of Animal Biotechnology and Disease Control and Prevention, Shandong Agricultural University, Taian City, Shandong Province, 271018, China; College of Veterinary Medicine, Shandong Agricultural University, Taian City, Shandong Province, 271018, China; Shandong Provincial Engineering Technology Research Center of Animal Disease Control and Prevention, Shandong Agricultural University, Taian City, Shandong Province, 271018, China.
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Singh J, Aballay A. Intestinal infection regulates behavior and learning via neuroendocrine signaling. eLife 2019; 8:e50033. [PMID: 31674907 PMCID: PMC6884406 DOI: 10.7554/elife.50033] [Citation(s) in RCA: 45] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2019] [Accepted: 10/31/2019] [Indexed: 12/14/2022] Open
Abstract
The recognition of pathogens and subsequent activation of defense responses are critical for the survival of organisms. The nematode Caenorhabditis elegans recognizes pathogenic bacteria and elicits defense responses by activating immune pathways and pathogen avoidance. Here we show that chemosensation of phenazines produced by pathogenic Pseudomonas aeruginosa, which leads to rapid activation of DAF-7/TGF-β in ASJ neurons, is insufficient for the elicitation of pathogen avoidance behavior. Instead, intestinal infection and bloating of the lumen, which depend on the virulence of P. aeruginosa, regulates both pathogen avoidance and aversive learning by modulating not only the DAF-7/TGF-β pathway but also the G-protein coupled receptor NPR-1 pathway, which also controls aerotaxis behavior. Modulation of these neuroendocrine pathways by intestinal infection serves as a systemic feedback that enables animals to avoid virulent bacteria. These results reveal how feedback from the intestine during infection can modulate the behavior, learning, and microbial perception of the host.
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Affiliation(s)
- Jogender Singh
- Department of Molecular Microbiology & ImmunologyOregon Health & Science UniversityPortlandUnited States
| | - Alejandro Aballay
- Department of Molecular Microbiology & ImmunologyOregon Health & Science UniversityPortlandUnited States
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Nhan JD, Turner CD, Anderson SM, Yen CA, Dalton HM, Cheesman HK, Ruter DL, Uma Naresh N, Haynes CM, Soukas AA, Pukkila-Worley R, Curran SP. Redirection of SKN-1 abates the negative metabolic outcomes of a perceived pathogen infection. Proc Natl Acad Sci U S A 2019; 116:22322-22330. [PMID: 31611372 PMCID: PMC6825279 DOI: 10.1073/pnas.1909666116] [Citation(s) in RCA: 52] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
Early host responses toward pathogens are essential for defense against infection. In Caenorhabditis elegans, the transcription factor, SKN-1, regulates cellular defenses during xenobiotic intoxication and bacterial infection. However, constitutive activation of SKN-1 results in pleiotropic outcomes, including a redistribution of somatic lipids to the germline, which impairs health and shortens lifespan. Here, we show that exposing C. elegans to Pseudomonas aeruginosa similarly drives the rapid depletion of somatic, but not germline, lipid stores. Modulating the epigenetic landscape refines SKN-1 activity away from innate immunity targets, which alleviates negative metabolic outcomes. Similarly, exposure to oxidative stress redirects SKN-1 activity away from pathogen response genes while restoring somatic lipid distribution. In addition, activating p38/MAPK signaling in the absence of pathogens, is sufficient to drive SKN-1-dependent loss of somatic fat. These data define a SKN-1- and p38-dependent axis for coordinating pathogen responses, lipid homeostasis, and survival and identify transcriptional redirection, rather than inactivation, as a mechanism for counteracting the pleiotropic consequences of aberrant transcriptional activity.
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Affiliation(s)
- James D Nhan
- Leonard Davis School of Gerontology, University of Southern California, Los Angeles, CA 90089
- Department of Molecular and Computation Biology, Dornsife College of Letters, Arts, and Sciences, University of Southern California, Los Angeles, CA 90089
| | - Christian D Turner
- Leonard Davis School of Gerontology, University of Southern California, Los Angeles, CA 90089
- Department of Molecular and Computation Biology, Dornsife College of Letters, Arts, and Sciences, University of Southern California, Los Angeles, CA 90089
| | - Sarah M Anderson
- Program in Innate Immunity, Division of Infectious Diseases and Immunology, University of Massachusetts Medical School, Worcester, MA 01655
| | - Chia-An Yen
- Leonard Davis School of Gerontology, University of Southern California, Los Angeles, CA 90089
- Department of Molecular and Computation Biology, Dornsife College of Letters, Arts, and Sciences, University of Southern California, Los Angeles, CA 90089
| | - Hans M Dalton
- Leonard Davis School of Gerontology, University of Southern California, Los Angeles, CA 90089
- Department of Molecular and Computation Biology, Dornsife College of Letters, Arts, and Sciences, University of Southern California, Los Angeles, CA 90089
| | - Hilary K Cheesman
- Program in Innate Immunity, Division of Infectious Diseases and Immunology, University of Massachusetts Medical School, Worcester, MA 01655
| | - Dana L Ruter
- Biology Department, Integrative Program for Biological and Genome Sciences, University of North Carolina, Chapel Hill, NC 27599
| | - Nandhitha Uma Naresh
- Department of Molecular, Cell and Cancer Biology, University of Massachusetts Medical School, Worcester, MA 01655
| | - Cole M Haynes
- Department of Molecular, Cell and Cancer Biology, University of Massachusetts Medical School, Worcester, MA 01655
| | - Alexander A Soukas
- Center for Human Genetic Research and Diabetes Unit, Department of Medicine, Massachusetts General Hospital, Boston, MA 02114
| | - Read Pukkila-Worley
- Program in Innate Immunity, Division of Infectious Diseases and Immunology, University of Massachusetts Medical School, Worcester, MA 01655;
| | - Sean P Curran
- Leonard Davis School of Gerontology, University of Southern California, Los Angeles, CA 90089;
- Department of Molecular and Computation Biology, Dornsife College of Letters, Arts, and Sciences, University of Southern California, Los Angeles, CA 90089
- Norris Comprehensive Cancer Center, Keck School of Medicine, University of Southern California, Los Angeles, CA 90089
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61
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Barbosa C, Römhild R, Rosenstiel P, Schulenburg H. Evolutionary stability of collateral sensitivity to antibiotics in the model pathogen Pseudomonas aeruginosa. eLife 2019; 8:e51481. [PMID: 31658946 PMCID: PMC6881144 DOI: 10.7554/elife.51481] [Citation(s) in RCA: 44] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2019] [Accepted: 10/21/2019] [Indexed: 12/27/2022] Open
Abstract
Evolution is at the core of the impending antibiotic crisis. Sustainable therapy must thus account for the adaptive potential of pathogens. One option is to exploit evolutionary trade-offs, like collateral sensitivity, where evolved resistance to one antibiotic causes hypersensitivity to another one. To date, the evolutionary stability and thus clinical utility of this trade-off is unclear. We performed a critical experimental test on this key requirement, using evolution experiments with Pseudomonas aeruginosa, and identified three main outcomes: (i) bacteria commonly failed to counter hypersensitivity and went extinct; (ii) hypersensitivity sometimes converted into multidrug resistance; and (iii) resistance gains frequently caused re-sensitization to the previous drug, thereby maintaining the trade-off. Drug order affected the evolutionary outcome, most likely due to variation in the effect size of collateral sensitivity, epistasis among adaptive mutations, and fitness costs. Our finding of robust genetic trade-offs and drug-order effects can guide design of evolution-informed antibiotic therapy.
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Affiliation(s)
- Camilo Barbosa
- Department of Evolutionary Ecology and GeneticsUniversity of KielKielGermany
| | - Roderich Römhild
- Department of Evolutionary Ecology and GeneticsUniversity of KielKielGermany
- Max Planck Institute for Evolutionary BiologyPlönGermany
| | | | - Hinrich Schulenburg
- Department of Evolutionary Ecology and GeneticsUniversity of KielKielGermany
- Max Planck Institute for Evolutionary BiologyPlönGermany
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62
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Oviedo JM, Surmann K, Gorgojo JP, Valdez H, Dhople VM, Lamberti Y, Völker U, Rodriguez ME. Shotgun proteomic analysis of Bordetella parapertussis provides insights into the physiological response to iron starvation and potential new virulence determinants absent in Bordetella pertussis. J Proteomics 2019; 206:103448. [PMID: 31325608 DOI: 10.1016/j.jprot.2019.103448] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2019] [Revised: 06/19/2019] [Accepted: 07/11/2019] [Indexed: 01/05/2023]
Abstract
Bordetella parapertussis is one of the pathogens that cause whooping cough. Even though its incidence has been rising in the last decades, this species remained poorly investigated. This study reports the first extensive proteome analysis of this bacterium. In an attempt to gain some insight into the infective phenotype, we evaluated the response of B. parapertussis to iron starvation, a critical stress the bacteria face during infection. Among other relevant findings, we observed that the adaptation to this condition involves significant changes in the abundance of two important virulence factors of this pathogen, namely, adenylate cyclase and the O-antigen. We further used the proteomic data to search for B. parapertussis proteins that are absent or classified as pseudogenes in the genome of Bordetella pertussis to unravel differences between both whooping cough causative agents. Among them, we identified proteins involved in stress resistance and virulence determinants that might help to explain the differences in the pathogenesis of these species and the lack of cross-protection of current acellular vaccines. Altogether, these results contribute to a better understanding of B. parapertussis biology and pathogenesis. SIGNIFICANCE: Whooping cough is a reemerging disease caused by both Bordetella pertussis and Bordetella parapertussis. Current vaccines fail to induce protection against B parapertussis and the incidence of this species has been rising over the years. The proteomic analysis of this study provided relevant insights into potential virulence determinants of this poorly-studied pathogen. It further identified proteins produced by B. parapertussis not present in B. pertussis, which might help to explain both the differences on their respective infectious process and the current vaccine failure. Altogether, the results of this study contribute to the better understanding of B. parapertussis pathogenesis and the eventual design of improved preventive strategies against whooping cough.
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Affiliation(s)
- Juan Marcos Oviedo
- CINDEFI (UNLP CONICET La Plata), Facultad de Ciencias Exactas, Universidad Nacional de La Plata, La Plata, Argentina
| | - Kristin Surmann
- Department of Functional Genomics, Interfaculty Institute for Genetics and Functional Genomics, University Medicine Greifswald, Greifswald, Germany
| | - Juan Pablo Gorgojo
- CINDEFI (UNLP CONICET La Plata), Facultad de Ciencias Exactas, Universidad Nacional de La Plata, La Plata, Argentina
| | - Hugo Valdez
- CINDEFI (UNLP CONICET La Plata), Facultad de Ciencias Exactas, Universidad Nacional de La Plata, La Plata, Argentina
| | - Vishnu M Dhople
- Department of Functional Genomics, Interfaculty Institute for Genetics and Functional Genomics, University Medicine Greifswald, Greifswald, Germany
| | - Yanina Lamberti
- CINDEFI (UNLP CONICET La Plata), Facultad de Ciencias Exactas, Universidad Nacional de La Plata, La Plata, Argentina
| | - Uwe Völker
- Department of Functional Genomics, Interfaculty Institute for Genetics and Functional Genomics, University Medicine Greifswald, Greifswald, Germany
| | - María Eugenia Rodriguez
- CINDEFI (UNLP CONICET La Plata), Facultad de Ciencias Exactas, Universidad Nacional de La Plata, La Plata, Argentina.
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63
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Modulation of Pseudomonas aeruginosa Quorum Sensing by Glutathione. J Bacteriol 2019; 201:JB.00685-18. [PMID: 30782628 DOI: 10.1128/jb.00685-18] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2018] [Accepted: 02/07/2019] [Indexed: 01/24/2023] Open
Abstract
Pseudomonas aeruginosa uses quorum sensing (QS) to regulate the production of a battery of secreted products. At least some of these products are shared among the population and serve as public goods. When P. aeruginosa is grown on casein as the sole carbon and energy source, the QS-induced extracellular protease elastase is required for growth. We isolated a P. aeruginosa variant, which showed increased production of QS-induced factors after repeated transfers in casein broth. This variant, P. aeruginosa QS*, had a mutation in the glutathione synthesis gene gshA We describe several experiments that show a gshA coding variant and glutathione affect the QS response. The P. aeruginosa QS transcription factor LasR has a redox-sensitive cysteine (C79). We report that GshA variant cells with a LasR C79S substitution show a similar QS response to that of wild-type P. aeruginosa Surprisingly, it is not LasR but the QS transcription factor RhlR that is more active in bacteria containing the variant gshA Our results demonstrate that QS integrates information about cell density and the cellular redox state via glutathione levels.IMPORTANCE Pseudomonas aeruginosa and other bacteria coordinate group behaviors using a chemical communication system called quorum sensing (QS). The QS system of P. aeruginosa is complex, with several regulators and signals. We show that decreased levels of glutathione lead to increased gene activation in P. aeruginosa, which did not occur in a strain carrying the redox-insensitive variant of a transcription factor. The ability of P. aeruginosa QS transcription factors to integrate information about cell density and cellular redox state shows these transcription factors can fine-tune levels of the gene products they control in response to at least two types of signals or cues.
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64
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Huang C, Niethammer P. Tissue Damage Signaling Is a Prerequisite for Protective Neutrophil Recruitment to Microbial Infection in Zebrafish. Immunity 2019; 48:1006-1013.e6. [PMID: 29768163 DOI: 10.1016/j.immuni.2018.04.020] [Citation(s) in RCA: 26] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2017] [Revised: 04/04/2018] [Accepted: 04/17/2018] [Indexed: 12/28/2022]
Abstract
Tissue damage and infection are deemed likewise triggers of innate immune responses. But whereas neutrophil responses to microbes are generally protective, neutrophil recruitment into damaged tissues without infection is deleterious. Why neutrophils respond to tissue damage and not just to microbes is unknown. Is it a flaw of the innate immune system that persists because evolution did not select against it, or does it provide a selective advantage? Here we dissect the contribution of tissue damage signaling to antimicrobial immune responses in a live vertebrate. By intravital imaging of zebrafish larvae, a powerful model for innate immunity, we show that prevention of tissue damage signaling upon microbial ear infection abrogates leukocyte chemotaxis and reduces animal survival, at least in part, through suppression of cytosolic phospholipase A2 (cPla2), which integrates tissue damage- and microbe-derived cues. Thus, microbial cues are insufficient, and damage signaling is essential for antimicrobial neutrophil responses in zebrafish.
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Affiliation(s)
- Cong Huang
- Cell Biology Program, Memorial Sloan Kettering Cancer Center, New York, NY 10065, USA; BCMB Allied Program, Weill Cornell Medical College, 1300 York Avenue, New York, NY 10065, USA
| | - Philipp Niethammer
- Cell Biology Program, Memorial Sloan Kettering Cancer Center, New York, NY 10065, USA.
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65
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Joshi C, Patel P, Palep H, Kothari V. Validation of the anti-infective potential of a polyherbal 'Panchvalkal' preparation, and elucidation of the molecular basis underlining its efficacy against Pseudomonas aeruginosa. BMC COMPLEMENTARY AND ALTERNATIVE MEDICINE 2019; 19:19. [PMID: 30654785 PMCID: PMC6335721 DOI: 10.1186/s12906-019-2428-5] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/08/2018] [Accepted: 01/02/2019] [Indexed: 02/02/2023]
Abstract
BACKGROUND A Panchvalkal formulation (Pentaphyte P-5®) mentioned in ancient texts of Indian traditional medicine was investigated for its anti-infective potential against Pseudomonas aeruginosa. METHODS Effect of the test formulation on bacterial growth and pigment production was evaluated by broth dilution assay. In vivo efficacy was evaluated using Caenorhabditis elegans as the model host. Whole transcriptome approach was taken to study the effect of test formulation on bacterial gene expression. RESULTS This formulation in vitro was found to be capable of affecting quorum sensing (QS)-regulated traits (pyocyanin, pyoverdine, biofilm) of Pseudomonas aeruginosa. In combination with antibiotics, it enhanced susceptibility of the test bacterium to antibiotics like cephalexin and tetracycline. Effect of Panchvalkal formulation (PF) on QS-regulated traits of P. aeruginosa was not reversed even after repeated exposure of the bacterium to PF. In vivo efficacy of PF was demonstrated employing Caenorhabditis elegans as the model host, wherein PF-treated bacteria were able to kill lesser worms than their extract-unexposed counterparts. Whole transcriptome study revealed that approximately 14% of the P. aeruginosa genome was expressed differently under the influence of PF. CONCLUSIONS Major mechanisms through which Panchvalkal seems to exert its anti-virulence effect are generation of nitrosative and oxidative stress, and disturbing iron and molybdenum homeostasis, besides interfering with QS machinery. This study is a good demonstration of the therapeutic utility of the 'polyherbalism' concept, so common in ayurved. It also demonstrates utility of the modern 'omics' tools for validating the traditional medicine i.e. ayuromics.
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Affiliation(s)
- Chinmayi Joshi
- Institute of Science, Nirma University, Ahmedabad, 382481 India
| | - Pooja Patel
- Institute of Science, Nirma University, Ahmedabad, 382481 India
| | | | - Vijay Kothari
- Institute of Science, Nirma University, Ahmedabad, 382481 India
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66
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Manan A, Bazai ZA, Fan J, Yu H, Li L. The Nif3-Family Protein YqfO03 from Pseudomonas syringae MB03 Has Multiple Nematicidal Activities against Caenorhabditis elegans and Meloidogyne incognita. Int J Mol Sci 2018; 19:ijms19123915. [PMID: 30563288 PMCID: PMC6321441 DOI: 10.3390/ijms19123915] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2018] [Revised: 11/20/2018] [Accepted: 12/04/2018] [Indexed: 11/29/2022] Open
Abstract
The nematicidal activity of the common plant-pathogenic bacterium Pseudomonas syringae against certain nematodes has been recently identified, but little is known about its virulence factors. In the current study, predictive analysis of nematode-virulent factors in the genome of a P. syringae wild-type strain MB03 revealed a variety of factors with the potential to be pathogenic against nematodes. One of these virulence factors that was predicted with a high score, namely, YqfO03, was a protein with structural domains that are similar to the Nif3 superfamily. This protein was expressed and purified in Escherichia coli, and was investigated for nematicidal properties against the model nematode Caenorhabditis elegans and an agriculturally important pest Meloidogyne incognita. Our results showed that YqfO03 exhibits lethal activity toward C. elegans and M. incognita worms, and it also caused detrimental effects on the growth, brood size, and motility of C. elegans worms. However, C. elegans worms were able to defend themselves against YqfO03 via a physical defense response by avoiding contact with the protein. Discovery of the diverse nematicidal activities of YqfO03 provides new knowledge on the biological function of a bacterial Nif3-family protein and insight into the potential of this protein as a specific means of controlling agricultural nematode pests.
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Affiliation(s)
- Abdul Manan
- State Key Laboratory of Agricultural Microbiology, College of Life Science and Technology, Huazhong Agricultural University, Wuhan 430070, China.
- Center for Advance Studies in Vaccinology and Biotechnology, University of Baluchistan, Quetta 87300, Pakistan.
| | - Zahoor Ahmad Bazai
- Department of Botany, University of Baluchistan, Quetta 87300, Pakistan.
| | - Jin Fan
- State Key Laboratory of Agricultural Microbiology, College of Life Science and Technology, Huazhong Agricultural University, Wuhan 430070, China.
| | - Huafu Yu
- State Key Laboratory of Agricultural Microbiology, College of Life Science and Technology, Huazhong Agricultural University, Wuhan 430070, China.
| | - Lin Li
- State Key Laboratory of Agricultural Microbiology, College of Life Science and Technology, Huazhong Agricultural University, Wuhan 430070, China.
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67
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Fernández M, Corral-Lugo A, Krell T. The plant compound rosmarinic acid induces a broad quorum sensing response in Pseudomonas aeruginosa PAO1. Environ Microbiol 2018; 20:4230-4244. [PMID: 30051572 DOI: 10.1111/1462-2920.14301] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2018] [Accepted: 05/28/2018] [Indexed: 02/05/2023]
Abstract
The interference of plant compounds with bacterial quorum sensing (QS) is a major mechanism through which plants and bacteria communicate. However, little is known about the modes of action and effects on signal integrity during this type of communication. We have recently shown that the plant compound rosmarinic acid (RA) specifically binds to the Pseudomonas aeruginosa RhlR QS receptor. To determine the effect of RA on expression patterns, we carried out global RNA-seq analysis. The results show that RA induces the expression of 128 genes, amongst which many virulence factor genes. RA triggers a broad QS response because 88% of the induced genes are known to be controlled by QS, and because RA stimulated genes were found to be involved in all four QS signalling systems within P. aeruginosa. This finding was confirmed through the analysis of transcriptional fusions transferred to wt and a rhlI/lasI double mutant. RA did not induce gene expression in the rhlI/lasI/rhlR triple mutant indicating that the effects observed are due to the RA-RhlR interaction. Furthermore, RA induced seven sRNAs that were all encoded in regions close to QS and/or RA induced genes. This work significantly enhances our understanding of plant bacteria interaction.
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Affiliation(s)
- Matilde Fernández
- Department of Environmental Protection, Estación Experimental del Zaidín, Consejo Superior de Investigaciones Científicas, Granada, Spain
| | - Andrés Corral-Lugo
- Department of Environmental Protection, Estación Experimental del Zaidín, Consejo Superior de Investigaciones Científicas, Granada, Spain
- Institut de Biologie Intégrative de la Cellule (I2BC), CNRS, Gif-Sur-Yvette, France
| | - Tino Krell
- Department of Environmental Protection, Estación Experimental del Zaidín, Consejo Superior de Investigaciones Científicas, Granada, Spain
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68
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Hickey C, Schaible B, Nguyen S, Hurley D, Srikumar S, Fanning S, Brown E, Crifo B, Matallanas D, McClean S, Taylor CT, Schaffer K. Increased Virulence of Bloodstream Over Peripheral Isolates of P. aeruginosa Identified Through Post-transcriptional Regulation of Virulence Factors. Front Cell Infect Microbiol 2018; 8:357. [PMID: 30416988 PMCID: PMC6212473 DOI: 10.3389/fcimb.2018.00357] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2018] [Accepted: 09/18/2018] [Indexed: 11/13/2022] Open
Abstract
The factors influencing the virulence of P. aeruginosa in the development of invasive infection remain poorly understood. Here, we investigated the role of the host microenvironment in shaping pathogen virulence and investigated the mechanisms involved. Comparing seven paired genetically indistinguishable clinical bloodstream and peripheral isolates of P. aeruginosa, we demonstrate that isolates derived from bloodstream infections are more virulent than their peripheral counterparts (p = 0.025). Bloodstream and peripheral isolates elicited similar NF-kB responses in a THP-1 monocyte NF-kappaB reporter cell line implicating similar immunogenicity. Proteomic analysis by mass spectrometry identified multiple virulence and virulence-related factors including LecA and RpoN in significantly greater abundance in the bacterial supernatant from the bloodstream isolate in comparison to that from the corresponding peripheral isolate. Investigation by qPCR revealed that control of expression of these virulence factors was not due to altered levels of transcription. Based on these data, we hypothesize a post-transcriptional mechanism of virulence regulation in P. aeruginosa bloodstream infections influenced by surrounding microenvironmental conditions.
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Affiliation(s)
| | | | - Scott Nguyen
- School of Public Health, Physiotherapy & Sports Science, University College Dublin, Dublin, Ireland
| | - Daniel Hurley
- School of Public Health, Physiotherapy & Sports Science, University College Dublin, Dublin, Ireland
| | - Shabarinath Srikumar
- School of Public Health, Physiotherapy & Sports Science, University College Dublin, Dublin, Ireland
| | - Séamus Fanning
- School of Public Health, Physiotherapy & Sports Science, University College Dublin, Dublin, Ireland
| | - Eric Brown
- Conway Institute, University College Dublin, Dublin, Ireland
| | - Bianca Crifo
- Conway Institute, University College Dublin, Dublin, Ireland
| | - David Matallanas
- Systems Biology Ireland, University College Dublin, Dublin, Ireland.,School of Medicine, University College Dublin, Dublin, Ireland
| | - Siobhán McClean
- Biomedical and Biomolecular Science, University College Dublin, Dublin, Ireland
| | - Cormac T Taylor
- Conway Institute, University College Dublin, Dublin, Ireland.,Systems Biology Ireland, University College Dublin, Dublin, Ireland.,School of Medicine, University College Dublin, Dublin, Ireland
| | - Kirsten Schaffer
- School of Medicine, University College Dublin, Dublin, Ireland.,Department of Clinical Microbiology, St. Vincent's University Hospital, Dublin, Ireland
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69
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Liu Q, Liu Y, Kang Z, Xiao D, Gao C, Xu P, Ma C. 2,3-Butanediol catabolism in Pseudomonas aeruginosa PAO1. Environ Microbiol 2018; 20:3927-3940. [PMID: 30058099 DOI: 10.1111/1462-2920.14332] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2018] [Accepted: 06/18/2018] [Indexed: 11/28/2022]
Abstract
2,3-Butanediol (2,3-BD) is a primary microbial metabolite that enhances the virulence of Pseudomonas aeruginosa and alters the lung microbiome. 2,3-BD exists in three stereoisomeric forms: (2R,3R)-2,3-BD, meso-2,3-BD and (2S,3S)-2,3-BD. In this study, we investigated whether and how P. aeruginosa PAO1 utilizes these 2,3-BD stereoisomers and showed that all three stereoisomers were transformed into acetoin by (2R,3R)-2,3-butanediol dehydrogenase (BDH) or (2S,3S)-2,3-BDH. Acetoin was cleaved to form acetyl-CoA and acetaldehyde by acetoin dehydrogenase enzyme system (AoDH ES). Genes encoding (2R,3R)-2,3-BDH, (2S,3S)-2,3-BDH and the E1 and E2 components of AoDH ES were identified as part of a new 2,3-BD utilization operon. In addition, the regulatory protein AcoR promoted the expression of this operon using acetaldehyde, a cleavage product of acetoin, as its direct effector. The results of this study elucidate the integrated catabolic role of 2,3-BD and may provide new insights in P. aeruginosa-related infections.
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Affiliation(s)
- Qiuyuan Liu
- State Key Laboratory of Microbial Technology, Shandong University, Jinan 250100, People's Republic of China
| | - Yidong Liu
- State Key Laboratory of Microbial Technology, Shandong University, Jinan 250100, People's Republic of China
| | - Zhaoqi Kang
- State Key Laboratory of Microbial Technology, Shandong University, Jinan 250100, People's Republic of China
| | - Dan Xiao
- State Key Laboratory of Microbial Technology, Shandong University, Jinan 250100, People's Republic of China
| | - Chao Gao
- State Key Laboratory of Microbial Technology, Shandong University, Jinan 250100, People's Republic of China
| | - Ping Xu
- State Key Laboratory of Microbial Metabolism, Joint International Research Laboratory of Metabolic & Developmental Sciences, and School of Life Sciences & Biotechnology, Shanghai Jiao Tong University, Shanghai 200240, People's Republic of China
| | - Cuiqing Ma
- State Key Laboratory of Microbial Technology, Shandong University, Jinan 250100, People's Republic of China.,Shenzhen Research Institute of Shandong University, Shenzhen 518057, People's Republic of China
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70
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Pseudomonas aeruginosa type IV minor pilins and PilY1 regulate virulence by modulating FimS-AlgR activity. PLoS Pathog 2018; 14:e1007074. [PMID: 29775484 PMCID: PMC5979040 DOI: 10.1371/journal.ppat.1007074] [Citation(s) in RCA: 41] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2018] [Revised: 05/31/2018] [Accepted: 05/04/2018] [Indexed: 11/19/2022] Open
Abstract
Type IV pili are expressed by a wide range of prokaryotes, including the opportunistic pathogen Pseudomonas aeruginosa. These flexible fibres mediate twitching motility, biofilm maturation, surface adhesion, and virulence. The pilus is composed mainly of major pilin subunits while the low abundance minor pilins FimU-PilVWXE and the putative adhesin PilY1 prime pilus assembly and are proposed to form the pilus tip. The minor pilins and PilY1 are encoded in an operon that is positively regulated by the FimS-AlgR two-component system. Independent of pilus assembly, PilY1 was proposed to be a mechanosensory component that—in conjunction with minor pilins—triggers up-regulation of acute virulence phenotypes upon surface attachment. Here, we investigated the link between the minor pilins/PilY1 and virulence. pilW, pilX, and pilY1 mutants had reduced virulence towards Caenorhabditis elegans relative to wild type or a major pilin mutant, implying a role in pathogenicity that is independent of pilus assembly. We hypothesized that loss of specific minor pilins relieves feedback inhibition on FimS-AlgR, increasing transcription of the AlgR regulon and delaying C. elegans killing. Reporter assays confirmed that FimS-AlgR were required for increased expression of the minor pilin operon upon loss of select minor pilins. Overexpression of AlgR or its hyperactivation via a phosphomimetic mutation reduced virulence, and the virulence defects of pilW, pilX, and pilY1 mutants required FimS-AlgR expression and activation. We propose that PilY1 and the minor pilins inhibit their own expression, and that loss of these proteins leads to FimS-mediated activation of AlgR that suppresses expression of acute-phase virulence factors and delays killing. This mechanism could contribute to adaptation of P. aeruginosa in chronic lung infections, as mutations in the minor pilin operon result in the loss of piliation and increased expression of AlgR-dependent virulence factors–such as alginate–that are characteristic of such infections. Pseudomonas aeruginosa causes dangerous infections, including chronic lung infections in cystic fibrosis patients. It uses many strategies to infect its hosts, including deployment of grappling hook-like fibres called type IV pili. Among the components involved in assembly and function of the pilus are five proteins called minor pilins that—along with a larger protein called PilY1—may help the pilus attach to surfaces. In a roundworm infection model, loss of PilY1 and specific minor pilins delayed killing, while loss of other pilus components did not. We traced this effect to increased activation of the FimS-AlgR regulatory system that inhibits the expression of virulence factors used early in infection, while positively regulating chronic infection traits such as alginate production, a phenotype called mucoidy. A disruption in the appropriate timing of FimS-AlgR-dependent virulence factor expression when select minor pilins or PilY1 are missing may explain why those pilus-deficient mutants have reduced virulence compared with others whose products are not under FimS-AlgR control. Increased FimS-AlgR activity upon loss of PilY1 and specific minor pilins could help to explain the frequent co-occurrence of the non-piliated and mucoid phenotypes that are hallmarks of chronic P. aeruginosa lung infections.
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Drenkard E, Hibbler RM, Gutu DA, Eaton AD, Silverio AL, Ausubel FM, Hurley BP, Yonker LM. Replication of the Ordered, Nonredundant Library of Pseudomonas aeruginosa strain PA14 Transposon Insertion Mutants. J Vis Exp 2018. [PMID: 29781996 DOI: 10.3791/57298] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/31/2022] Open
Abstract
Pseudomonas aeruginosa is a phenotypically and genotypically diverse and adaptable Gram-negative bacterium ubiquitous in human environments. P. aeruginosa is able to form biofilms, develop antibiotic resistance, produce virulence factors, and rapidly evolve in the course of a chronic infection. Thus P. aeruginosa can cause both acute and chronic, difficult to treat infections, resulting in significant morbidity in certain patient populations. P. aeruginosa strain PA14 is a human clinical isolate with a conserved genome structure that infects a variety of mammalian and nonvertebrate hosts making PA14 an attractive strain for studying this pathogen. In 2006, a nonredundant transposon insertion mutant library containing 5,459 mutants corresponding to 4,596 predicted PA14 genes was generated. Since then, distribution of the PA14 library has allowed the research community to better understand the function of individual genes and complex pathways of P. aeruginosa. Maintenance of library integrity through the replication process requires proper handling and precise techniques. To that end, this manuscript presents protocols that describe in detail the steps involved in library replication, library quality control and proper storage of individual mutants.
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Affiliation(s)
- Eliana Drenkard
- Department of Pediatrics, Mucosal Immunology and Biology Research Center, Massachusetts General Hospital
| | - Rhianna M Hibbler
- Department of Pediatrics, Mucosal Immunology and Biology Research Center, Massachusetts General Hospital
| | - D Alina Gutu
- Department of Molecular Biology, Massachusetts General Hospital
| | - Alexander D Eaton
- Department of Pediatrics, Mucosal Immunology and Biology Research Center, Massachusetts General Hospital
| | - Amy L Silverio
- Department of Pediatrics, Mucosal Immunology and Biology Research Center, Massachusetts General Hospital
| | - Frederick M Ausubel
- Department of Molecular Biology, Massachusetts General Hospital; Department of Genetics, Harvard Medical School
| | - Bryan P Hurley
- Department of Pediatrics, Mucosal Immunology and Biology Research Center, Massachusetts General Hospital; Department of Pediatrics, Harvard Medical School
| | - Lael M Yonker
- Department of Pediatrics, Mucosal Immunology and Biology Research Center, Massachusetts General Hospital; Department of Pediatrics, Harvard Medical School;
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72
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Pseudomonas aeruginosa gshA Mutant Is Defective in Biofilm Formation, Swarming, and Pyocyanin Production. mSphere 2018; 3:3/2/e00155-18. [PMID: 29669887 PMCID: PMC5907650 DOI: 10.1128/msphere.00155-18] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2018] [Accepted: 03/24/2018] [Indexed: 11/20/2022] Open
Abstract
Pseudomonas aeruginosa is a ubiquitous bacterium that can cause severe opportunistic infections, including many hospital-acquired infections. It is also a major cause of infections in patients with cystic fibrosis. P. aeruginosa is intrinsically resistant to a number of drugs and is capable of forming biofilms that are difficult to eradicate with antibiotics. The number of drug-resistant strains is also increasing, making treatment of P. aeruginosa infections very difficult. Thus, there is an urgent need to understand how P. aeruginosa causes disease in order to find novel ways to treat infections. We show that the principal redox buffer, glutathione (GSH), is involved in intrinsic resistance to the fosfomycin and rifampin antibiotics. We further demonstrate that GSH plays a role in P. aeruginosa disease and infection, since a mutant lacking GSH has less biofilm formation, is less able to swarm, and produces less pyocyanin, a pigment associated with infection. Pseudomonas aeruginosa is a ubiquitous Gram-negative bacterium that can cause severe opportunistic infections. The principal redox buffer employed by this organism is glutathione (GSH). To assess the role of GSH in the virulence of P. aeruginosa, a number of analyses were performed using a mutant strain deficient in gshA, which does not produce GSH. The mutant strain exhibited a growth delay in minimal medium compared to the wild-type strain. Furthermore, the gshA mutant was defective in biofilm and persister cell formation and in swimming and swarming motility and produced reduced levels of pyocyanin, a key virulence factor. Finally, the gshA mutant strain demonstrated increased sensitivity to methyl viologen (a redox cycling agent) as well as the thiol-reactive antibiotics fosfomycin and rifampin. Taken together, these data suggest a key role for GSH in the virulence of P. aeruginosa. IMPORTANCEPseudomonas aeruginosa is a ubiquitous bacterium that can cause severe opportunistic infections, including many hospital-acquired infections. It is also a major cause of infections in patients with cystic fibrosis. P. aeruginosa is intrinsically resistant to a number of drugs and is capable of forming biofilms that are difficult to eradicate with antibiotics. The number of drug-resistant strains is also increasing, making treatment of P. aeruginosa infections very difficult. Thus, there is an urgent need to understand how P. aeruginosa causes disease in order to find novel ways to treat infections. We show that the principal redox buffer, glutathione (GSH), is involved in intrinsic resistance to the fosfomycin and rifampin antibiotics. We further demonstrate that GSH plays a role in P. aeruginosa disease and infection, since a mutant lacking GSH has less biofilm formation, is less able to swarm, and produces less pyocyanin, a pigment associated with infection.
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73
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Chen YW, Ko WC, Chen CS, Chen PL. RIOK-1 Is a Suppressor of the p38 MAPK Innate Immune Pathway in Caenorhabditis elegans. Front Immunol 2018; 9:774. [PMID: 29719537 PMCID: PMC5913292 DOI: 10.3389/fimmu.2018.00774] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2017] [Accepted: 03/28/2018] [Indexed: 01/08/2023] Open
Abstract
Innate immunity is the primary defense mechanism against infection in metazoans. However, aberrant upregulation of innate immune-signaling pathways can also be detrimental to the host. The p38 MAPK/PMK-1 innate immune-signaling pathway has been demonstrated to play essential roles in cellular defenses against numerous infections in metazoans, including Caenorhabditis elegans. However, the negative regulators that maintain the homeostasis of this important innate immune pathway remain largely understudied. By screening a focused RNAi library against the kinome of C. elegans, we identified RIOK-1, a human RIO kinase homolog, as a novel suppressor of the p38 MAPK/PMK-1 signal pathway. We demonstrated that the suppression of riok-1 confers resistance to Aeromonas dhakensis infection in C. elegans. Using quantitative real time-PCR and riok-1 reporter worms, we found the expression levels of riok-1 to be significantly upregulated in worms infected with A. dhakensis. Our genetic epistasis analysis suggested that riok-1 acts on the upstream of the p38 MAPK/pmk-1 genetic pathway. Moreover, the suppression of riok-1 enhanced the p38 MAPK signal, suggesting that riok-1 is a negative regulator of this innate pathway in C. elegans. Our epistatic results put riok-1 downstream of skn-1, which encodes a p38 MAPK downstream transcription factor and serves as a feedback loop to the p38 MAPK pathway during an A. dhakensis infection. In conclusion, riok-1 is proposed as a novel innate immune suppressor and as a negative feedback loop model involving p38 MAPK, SKN-1, and RIOK-1 in C. elegans.
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Affiliation(s)
- Yi-Wei Chen
- Institute of Basic Medical Sciences, College of Medicine, National Cheng Kung University, Tainan, Taiwan
| | - Wen-Chien Ko
- Institute of Basic Medical Sciences, College of Medicine, National Cheng Kung University, Tainan, Taiwan.,Department of Internal Medicine, National Cheng Kung University Hospital, College of Medicine, National Cheng Kung University, Tainan, Taiwan
| | - Chang-Shi Chen
- Institute of Basic Medical Sciences, College of Medicine, National Cheng Kung University, Tainan, Taiwan.,Department of Biochemistry and Molecular Biology, College of Medicine, National Cheng Kung University, Tainan, Taiwan
| | - Po-Lin Chen
- Department of Internal Medicine, National Cheng Kung University Hospital, College of Medicine, National Cheng Kung University, Tainan, Taiwan.,Department of Microbiology and Immunology, College of Medicine, National Cheng Kung University, Tainan, Taiwan
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74
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Mechanistic insights into the allosteric regulation of Pseudomonas aeruginosa aspartate kinase. Biochem J 2018; 475:1107-1119. [PMID: 29382741 DOI: 10.1042/bcj20170829] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2017] [Revised: 01/18/2018] [Accepted: 01/24/2018] [Indexed: 02/05/2023]
Abstract
In plants and microorganisms, aspartate kinase (AK) catalyzes an initial commitment step of the aspartate family amino acid biosynthesis. Owing to various structural organizations, AKs from different species show tremendous diversity and complex allosteric controls. We report the crystal structure of AK from Pseudomonas aeruginosa (PaAK), a typical α2β2 hetero-tetrameric enzyme, in complex with inhibitory effectors. Distinctive features of PaAK are revealed by structural and biochemical analyses. Essentially, the open conformation of Lys-/Thr-bound PaAK structure clarifies the inhibitory mechanism of α2β2-type AK. Moreover, the various inhibitory effectors of PaAK have been identified and a general amino acid effector motif of AK family is described.
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Abstract
By assisting in the proteolysis, disaggregation and refolding of the aggregated proteins, Caseinolytic proteases (Clps) enhance the cellular survival under stress conditions. In the current study, comparative roles of two such Clps, ClpA (involved in proteolysis) and ClpB (involved in protein disaggregation and refolding) in the survival of Salmonella Typhimurium (S. Typhimurium) under different stresses and in virulence have been investigated. clpA and clpB gene deletion mutant strains (∆clpA and ∆clpB) of S. Typhimurium have been hypersensitive to 42 °C, HOCl and paraquat. However, the ∆clpB strain was comparatively much more susceptible (p < 0.001) to the above stresses than ∆clpA strain. ∆clpB strain also showed reduced survival (p < 0.001) in poultry macrophages. The hypersusceptibilities of ∆clpB strain to oxidants and macrophages were restored in plasmid based complemented (∆clpB + pclpB) strain. Further, the ∆clpB strain was defective for colonization in the poultry caecum and showed decreased dissemination to the spleen and liver. Our findings suggest that the role of ClpB is more important than the role of ClpA for the survival of S. Typhimurium under stress and colonization in chickens.
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76
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Haller S, Franchet A, Hakkim A, Chen J, Drenkard E, Yu S, Schirmeier S, Li Z, Martins N, Ausubel FM, Liégeois S, Ferrandon D. Quorum-sensing regulator RhlR but not its autoinducer RhlI enables Pseudomonas to evade opsonization. EMBO Rep 2018. [PMID: 29523648 DOI: 10.15252/embr.201744880] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
Abstract
When Drosophila melanogaster feeds on Pseudomonas aeruginosa, some bacteria cross the intestinal barrier and eventually proliferate in the hemocoel. This process is limited by hemocytes through phagocytosis. P. aeruginosa requires the quorum-sensing regulator RhlR to elude the cellular immune response of the fly. RhlI synthesizes the autoinducer signal that activates RhlR. Here, we show that rhlI mutants are unexpectedly more virulent than rhlR mutants, both in fly and in nematode intestinal infection models, suggesting that RhlR has RhlI-independent functions. We also report that RhlR protects P. aeruginosa from opsonization mediated by the Drosophila thioester-containing protein 4 (Tep4). RhlR mutant bacteria show higher levels of Tep4-mediated opsonization, as compared to rhlI mutants, which prevents lethal bacteremia in the Drosophila hemocoel. In contrast, in a septic model of infection, in which bacteria are introduced directly into the hemocoel, Tep4 mutant flies are more resistant to wild-type P. aeruginosa, but not to the rhlR mutant. Thus, depending on the infection route, the Tep4 opsonin can either be protective or detrimental to host defense.
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Affiliation(s)
- Samantha Haller
- CNRS, M3I UPR 9022, Université de Strasbourg, Strasbourg, France
| | - Adrien Franchet
- CNRS, M3I UPR 9022, Université de Strasbourg, Strasbourg, France
| | - Abdul Hakkim
- Department of Genetics, Harvard Medical School, Boston, MA, USA.,Department of Molecular Biology, Massachusetts General Hospital, Boston, MA, USA
| | - Jing Chen
- Sino-French Hoffmann Institute, Guangzhou Medical University, Guangzhou, China
| | - Eliana Drenkard
- Department of Genetics, Harvard Medical School, Boston, MA, USA.,Department of Molecular Biology, Massachusetts General Hospital, Boston, MA, USA
| | - Shen Yu
- Department of Genetics, Harvard Medical School, Boston, MA, USA.,Department of Molecular Biology, Massachusetts General Hospital, Boston, MA, USA
| | | | - Zi Li
- Sino-French Hoffmann Institute, Guangzhou Medical University, Guangzhou, China
| | - Nelson Martins
- CNRS, M3I UPR 9022, Université de Strasbourg, Strasbourg, France
| | - Frederick M Ausubel
- Department of Genetics, Harvard Medical School, Boston, MA, USA.,Department of Molecular Biology, Massachusetts General Hospital, Boston, MA, USA
| | - Samuel Liégeois
- CNRS, M3I UPR 9022, Université de Strasbourg, Strasbourg, France
| | - Dominique Ferrandon
- CNRS, M3I UPR 9022, Université de Strasbourg, Strasbourg, France .,Sino-French Hoffmann Institute, Guangzhou Medical University, Guangzhou, China
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Kuo CJ, Wang ST, Lin CM, Chiu HC, Huang CR, Lee DY, Chang GD, Chou TC, Chen JW, Chen CS. A multi-omic analysis reveals the role of fumarate in regulating the virulence of enterohemorrhagic Escherichia coli. Cell Death Dis 2018. [PMID: 29515100 PMCID: PMC5841434 DOI: 10.1038/s41419-018-0423-2] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
The enteric pathogen enterohemorrhagic Escherichia coli (EHEC) is responsible for outbreaks of bloody diarrhea and hemolytic uremic syndrome (HUS) worldwide. Several molecular mechanisms have been described for the pathogenicity of EHEC; however, the role of bacterial metabolism in the virulence of EHEC during infection in vivo remains unclear. Here we show that aerobic metabolism plays an important role in the regulation of EHEC virulence in Caenorhabditis elegans. Our functional genomic analyses showed that disruption of the genes encoding the succinate dehydrogenase complex (Sdh) of EHEC, including the sdhA gene, attenuated its toxicity toward C. elegans animals. Sdh converts succinate to fumarate and links the tricarboxylic acid (TCA) cycle and the electron transport chain (ETC) simultaneously. Succinate accumulation and fumarate depletion in the EHEC sdhA mutant cells were also demonstrated to be concomitant by metabolomic analyses. Moreover, fumarate replenishment to the sdhA mutant significantly increased its virulence toward C. elegans. These results suggest that the TCA cycle, ETC, and alteration in metabolome all account for the attenuated toxicity of the sdhA mutant, and Sdh catabolite fumarate in particular plays a critical role in the regulation of EHEC virulence. In addition, we identified the tryptophanase (TnaA) as a downstream virulence determinant of SdhA using a label-free proteomic method. We demonstrated that expression of tnaA is regulated by fumarate in EHEC. Taken together, our multi-omic analyses demonstrate that sdhA is required for the virulence of EHEC, and aerobic metabolism plays important roles in the pathogenicity of EHEC infection in C. elegans. Moreover, our study highlights the potential targeting of SdhA, if druggable, as alternative preventive or therapeutic strategies by which to combat EHEC infection.
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Affiliation(s)
- Cheng-Ju Kuo
- Department of Biochemistry and Molecular Biology, College of Medicine, National Cheng Kung University, Tainan, Taiwan.,Institute of Basic Medical Sciences, College of Medicine, National Cheng Kung University, Tainan, Taiwan
| | - Sin-Tian Wang
- Institute of Basic Medical Sciences, College of Medicine, National Cheng Kung University, Tainan, Taiwan
| | - Chia-Mei Lin
- Department of Biochemistry and Molecular Biology, College of Medicine, National Cheng Kung University, Tainan, Taiwan
| | - Hao-Chieh Chiu
- Department of Clinical Laboratory Sciences and Medical Biotechnology, National Taiwan University, Taipei, Taiwan
| | - Cheng-Rung Huang
- Department of Biochemistry and Molecular Biology, College of Medicine, National Cheng Kung University, Tainan, Taiwan.,Institute of Basic Medical Sciences, College of Medicine, National Cheng Kung University, Tainan, Taiwan
| | - Der-Yen Lee
- The Graduate Institute of Integrated Medicine, China Medical University, Taichung, Taiwan.,Graduate Institute of Biochemical Sciences, Technology Commons, Center for Systems Biology, National Taiwan University, Taipei, Taiwan
| | - Geen-Dong Chang
- Graduate Institute of Biochemical Sciences, Technology Commons, Center for Systems Biology, National Taiwan University, Taipei, Taiwan
| | - Ting-Chen Chou
- Department of Biochemistry and Molecular Biology, College of Medicine, National Cheng Kung University, Tainan, Taiwan
| | - Jenn-Wei Chen
- Institute of Basic Medical Sciences, College of Medicine, National Cheng Kung University, Tainan, Taiwan. .,Department of Microbiology and Immunology, College of Medicine, National Cheng Kung University, Tainan, Taiwan.
| | - Chang-Shi Chen
- Department of Biochemistry and Molecular Biology, College of Medicine, National Cheng Kung University, Tainan, Taiwan. .,Institute of Basic Medical Sciences, College of Medicine, National Cheng Kung University, Tainan, Taiwan.
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Liu L, Li T, Cheng XJ, Peng CT, Li CC, He LH, Ju SM, Wang NY, Ye TH, Lian M, Xiao QJ, Song YJ, Zhu YB, Yu LT, Wang ZL, Bao R. Structural and functional studies on Pseudomonas aeruginosa DspI: implications for its role in DSF biosynthesis. Sci Rep 2018; 8:3928. [PMID: 29500457 PMCID: PMC5834635 DOI: 10.1038/s41598-018-22300-1] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2017] [Accepted: 02/15/2018] [Indexed: 02/05/2023] Open
Abstract
DspI, a putative enoyl-coenzyme A (CoA) hydratase/isomerase, was proposed to be involved in the synthesis of cis-2-decenoic acid (CDA), a quorum sensing (QS) signal molecule in the pathogen Pseudomonas aeruginosa (P. aeruginosa). The present study provided a structural basis for the dehydration reaction mechanism of DspI during CDA synthesis. Structural analysis reveals that Glu126, Glu146, Cys127, Cys131 and Cys154 are important for its enzymatic function. Moreover, we show that the deletion of dspI results in a remarkable decreased in the pyoverdine production, flagella-dependent swarming motility, and biofilm dispersion as well as attenuated virulence in P. aeruginosa PA14. This study thus unravels the mechanism of DspI in diffusible signal factor (DSF) CDA biosynthesis, providing vital information for developing inhibitors that interfere with DSF associated pathogenicity in P. aeruginosa.
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Affiliation(s)
- Li Liu
- Center of Infectious Diseases, West China Hospital, Sichuan University, Chengdu, China
- Department of Dermatology, Southwest Medical University, affiliated hospital, Luzhou, China
| | - Tao Li
- Center of Infectious Diseases, West China Hospital, Sichuan University, Chengdu, China
| | - Xing-Jun Cheng
- Center of Infectious Diseases, West China Hospital, Sichuan University, Chengdu, China
| | - Cui-Ting Peng
- Center of Infectious Diseases, West China Hospital, Sichuan University, Chengdu, China
| | - Chang-Cheng Li
- Center of Infectious Diseases, West China Hospital, Sichuan University, Chengdu, China
| | - Li-Hui He
- Center of Infectious Diseases, West China Hospital, Sichuan University, Chengdu, China
| | - Si-Min Ju
- Center of Infectious Diseases, West China Hospital, Sichuan University, Chengdu, China
| | - Ning-Yu Wang
- School of Life Science and Engineering, Southwest Jiaotong University, Chengdu, China
| | - Ting-Hong Ye
- Center of Infectious Diseases, West China Hospital, Sichuan University, Chengdu, China
| | - Mao Lian
- Center of Infectious Diseases, West China Hospital, Sichuan University, Chengdu, China
| | - Qing-Jie Xiao
- Center of Infectious Diseases, West China Hospital, Sichuan University, Chengdu, China
| | - Ying-Jie Song
- Center of Infectious Diseases, West China Hospital, Sichuan University, Chengdu, China
| | - Yi-Bo Zhu
- Center of Infectious Diseases, West China Hospital, Sichuan University, Chengdu, China
| | - Luo-Ting Yu
- Center of Infectious Diseases, West China Hospital, Sichuan University, Chengdu, China.
| | - Zhen-Ling Wang
- Center of Infectious Diseases, West China Hospital, Sichuan University, Chengdu, China.
| | - Rui Bao
- Center of Infectious Diseases, West China Hospital, Sichuan University, Chengdu, China.
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Isolation and characterization of HepP: a virulence-related Pseudomonas aeruginosa heparinase. BMC Microbiol 2017; 17:233. [PMID: 29246112 PMCID: PMC5732420 DOI: 10.1186/s12866-017-1141-0] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2017] [Accepted: 12/05/2017] [Indexed: 12/15/2022] Open
Abstract
Background Pseudomonas aeruginosa is an opportunistic pathogen that causes serious infections in immunocompromised hosts including severely burned patients. In burn patients, P. aeruginosa infection often leads to septic shock and death. Despite numerous studies, the influence of severe thermal injuries on the pathogenesis of P. aeruginosa during systemic infection is not known. Through RNA-seq analysis, we recently showed that the growth of P. aeruginosa strain UCBPP-PA14 (PA14) in whole blood obtained from severely burned patients significantly altered the expression of the PA14 transcriptome when compared with its growth in blood from healthy volunteers. The expression of PA14_23430 and the adjacent gene, PA14_23420, was enhanced by seven- to eightfold under these conditions. Results Quantitative real-time PCR analysis confirmed the enhancement of expression of both PA14_23420 and PA14_23430 by growth of PA14 in blood from severely burned patients. Computer analysis revealed that PA14_23430 (hepP) encodes a potential heparinase while PA14_23420 (zbdP) codes for a putative zinc-binding dehydrogenase. This analysis further suggested that the two genes form an operon with zbdP first. Presence of the operon was confirmed by RT-PCR experiments. We characterized hepP and its protein product HepP. hepP was cloned from PA14 by PCR and overexpressed in E. coli. The recombinant protein (rHepP) was purified using nickel column chromatography. Heparinase assays using commercially available heparinase as a positive control, revealed that rHepP exhibits heparinase activity. Mutation of hepP resulted in delay of pellicle formation at the air-liquid interface by PA14 under static growth conditions. Biofilm formation by PA14ΔhepP was also significantly reduced. In the Caenorhabditis elegans model of slow killing, mutation of hepP resulted in a significantly lower rate of killing than that of the parent strain PA14. Conclusions Changes within the blood of severely burned patients significantly induced expression of hepP in PA14. The heparinase encoded by hepP is a potential virulence factor for PA14 as HepP influences pellicle formation as well as biofilm development by PA14 and the protein is required for full virulence in the C. elegans model of slow killing. Electronic supplementary material The online version of this article (10.1186/s12866-017-1141-0) contains supplementary material, which is available to authorized users.
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80
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Peng CT, Liu L, Li CC, He LH, Li T, Shen YL, Gao C, Wang NY, Xia Y, Zhu YB, Song YJ, Lei Q, Yu LT, Bao R. Structure-Function Relationship of Aminopeptidase P from Pseudomonas aeruginosa. Front Microbiol 2017; 8:2385. [PMID: 29259588 PMCID: PMC5723419 DOI: 10.3389/fmicb.2017.02385] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2017] [Accepted: 11/20/2017] [Indexed: 02/05/2023] Open
Abstract
PepP is a virulence-associated gene in Pseudomonas aeruginosa, making it an attractive target for anti-P. aeruginosa drug development. The encoded protein, aminopeptidases P (Pa-PepP), is a type of X-prolyl peptidase that possesses diverse biological functions. The crystal structure verified its canonical pita-bread fold and functional tetrameric assembly, and the functional studies measured the influences of different metal ions on the activity. A trimetal manganese cluster was observed at the active site, elucidating the mechanism of inhibition by metal ions. Additionally, a loop extending from the active site appeared to be important for specific large-substrate binding. Based on the structural comparison and bacterial invasion assays, we showed that this non-conserved surface loop was critical for P. aeruginosa virulence. Taken together, these findings can extend our understanding of the catalytic mechanism and virulence-related functions of Pa-PepP and provide a solid foundation for the design of specific inhibitors against pathogenic-bacterial infections.
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Affiliation(s)
- Cui-Ting Peng
- Pharmaceutical and Biological Engineering Department, School of Chemical Engineering, Sichuan University, Chengdu, China,Center of Infectious Diseases, State Key Laboratory of Biotherapy, West China Hospital, Sichuan University and Collaborative Innovation Center, Chengdu, China
| | - Li Liu
- Pharmaceutical and Biological Engineering Department, School of Chemical Engineering, Sichuan University, Chengdu, China,Center of Infectious Diseases, State Key Laboratory of Biotherapy, West China Hospital, Sichuan University and Collaborative Innovation Center, Chengdu, China
| | - Chang-Cheng Li
- Center of Infectious Diseases, State Key Laboratory of Biotherapy, West China Hospital, Sichuan University and Collaborative Innovation Center, Chengdu, China
| | - Li-Hui He
- Center of Infectious Diseases, State Key Laboratory of Biotherapy, West China Hospital, Sichuan University and Collaborative Innovation Center, Chengdu, China
| | - Tao Li
- Center of Infectious Diseases, State Key Laboratory of Biotherapy, West China Hospital, Sichuan University and Collaborative Innovation Center, Chengdu, China
| | - Ya-Lin Shen
- Center of Infectious Diseases, State Key Laboratory of Biotherapy, West China Hospital, Sichuan University and Collaborative Innovation Center, Chengdu, China
| | - Chao Gao
- Center of Infectious Diseases, State Key Laboratory of Biotherapy, West China Hospital, Sichuan University and Collaborative Innovation Center, Chengdu, China
| | - Ning-Yu Wang
- Center of Infectious Diseases, State Key Laboratory of Biotherapy, West China Hospital, Sichuan University and Collaborative Innovation Center, Chengdu, China,School of Life Sciences and Engineering, Southwest Jiaotong University, Chengdu, China
| | - Yong Xia
- Center of Infectious Diseases, State Key Laboratory of Biotherapy, West China Hospital, Sichuan University and Collaborative Innovation Center, Chengdu, China
| | - Yi-Bo Zhu
- Center of Infectious Diseases, State Key Laboratory of Biotherapy, West China Hospital, Sichuan University and Collaborative Innovation Center, Chengdu, China
| | - Ying-Jie Song
- Center of Infectious Diseases, State Key Laboratory of Biotherapy, West China Hospital, Sichuan University and Collaborative Innovation Center, Chengdu, China
| | - Qian Lei
- Center of Infectious Diseases, State Key Laboratory of Biotherapy, West China Hospital, Sichuan University and Collaborative Innovation Center, Chengdu, China
| | - Luo-Ting Yu
- Pharmaceutical and Biological Engineering Department, School of Chemical Engineering, Sichuan University, Chengdu, China,Center of Infectious Diseases, State Key Laboratory of Biotherapy, West China Hospital, Sichuan University and Collaborative Innovation Center, Chengdu, China,*Correspondence: Rui Bao, Luo-Ting Yu,
| | - Rui Bao
- Center of Infectious Diseases, State Key Laboratory of Biotherapy, West China Hospital, Sichuan University and Collaborative Innovation Center, Chengdu, China,*Correspondence: Rui Bao, Luo-Ting Yu,
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81
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Interplay among Resistance Profiles, High-Risk Clones, and Virulence in the Caenorhabditis elegans Pseudomonas aeruginosa Infection Model. Antimicrob Agents Chemother 2017; 61:AAC.01586-17. [PMID: 28923877 DOI: 10.1128/aac.01586-17] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2017] [Accepted: 09/15/2017] [Indexed: 12/22/2022] Open
Abstract
The increasing prevalence of nosocomial infections produced by multidrug-resistant (MDR) or extensively drug-resistant (XDR) Pseudomonas aeruginosa is frequently linked to widespread international strains designated high-risk clones. In this work, we attempted to decipher the interplay between resistance profiles, high-risk clones, and virulence, testing a large (n = 140) collection of well-characterized P. aeruginosa isolates from different sources (bloodstream infections, nosocomial outbreaks, cystic fibrosis, and the environment) in a Caenorhabditis elegans infection model. Consistent with previous data, we documented a clear inverse correlation between antimicrobial resistance and virulence in the C. elegans model. Indeed, the lowest virulence was linked to XDR profiles, which were typically linked to defined high-risk clones. However, virulence varied broadly depending on the involved high-risk clone; it was high for sequence type 111 (ST111) and ST235 but very low for ST175. The highest virulence of ST235 could be attributed to its exoU+ type III secretion system (TTSS) genotype, which was found to be linked with higher virulence in our C. elegans model. Other markers, such as motility or pigment production, were not essential for virulence in the C. elegans model but seemed to be related with the higher values of the statistical normalized data. In contrast to ST235, the ST175 high-risk clone, which is widespread in Spain and France, seems to be associated with a particularly low virulence in the C. elegans model. Moreover, the previously described G154R AmpR mutation, prevalent in ST175, was found to contribute to the reduced virulence, although it was not the only factor involved. Altogether, our results provide a major step forward for understanding the interplay between P. aeruginosa resistance profiles, high-risk clones, and virulence.
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82
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Kujawa M, Lirski M, Ziecina M, Drabinska J, Modzelan M, Kraszewska E. Nudix-type RNA pyrophosphohydrolase provides homeostasis of virulence factor pyocyanin and functions as a global regulator in Pseudomonas aeruginosa. Mol Microbiol 2017; 106:381-394. [PMID: 28833678 DOI: 10.1111/mmi.13771] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/11/2017] [Indexed: 12/26/2022]
Abstract
The PA0336 protein from Pseudomonas aeruginosa belongs to the family of widely distributed Nudix pyrophosphohydrolases, which catalyze the hydrolysis of pyrophosphate bonds in a variety of nucleoside diphosphate derivatives. The amino acid sequence of the PA0336 protein is highly similar to that of the RppH Nudix RNA pyrophosphohydrolase from Escherichia coli, which removes pyrophosphate from 5'-end of triphosphorylated RNA transcripts. Trans-complementation experiments showed that the P. aeruginosa enzyme can functionally substitute for RppH in E. coli cells indicating that, similar to RppH, the Pseudomonas hydrolase mediates RNA turnover in vivo. In order to elucidate the biological significance of the PA0336 protein in Pseudomonas cells, a PA0336 mutant strain was constructed. The mutated strain considerably increased level of the virulence factor pyocyanin compared to wild type, suggesting that PA0336 could be involved in downregulation of P. aeruginosa pathogenicity. This phenotype was reversed by complementation with the wild type but not catalytically inactive PA0336, indicating that the catalytic activity was indispensable for its biological function. Pathogenesis tests in Caenorhabditis elegans showed that the PA0336 mutant of P. aeruginosa was significantly more virulent than the parental strain, confirming further that the P. aeruginosa RNA pyrophosphohydrolase PA0336 modulates bacterial pathogenesis by down-regulating production of virulence-associated factors. To study the role of PA0336 further, transcriptomes of the PA0336 mutant and the wild-type strain were compared using RNA sequencing. The level of 537 transcripts coding for proteins involved in a variety of cellular processes such as replication, transcription, translation, central metabolism and pathogenesis, was affected by the lack of PA0336. These results indicate that the PA0336 RNA pyrophosphohydrolase functions as a global regulator that influences many of transcripts including those involved in P. aeruginosa virulence.
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Affiliation(s)
- Martyna Kujawa
- Institute of Biochemistry and Biophysics PAS, Pawińskiego 5A, 02-106 Warsaw, Poland
| | - Maciej Lirski
- Institute of Biochemistry and Biophysics PAS, Pawińskiego 5A, 02-106 Warsaw, Poland
| | - Mateusz Ziecina
- Institute of Biochemistry and Biophysics PAS, Pawińskiego 5A, 02-106 Warsaw, Poland
| | - Joanna Drabinska
- Institute of Biochemistry and Biophysics PAS, Pawińskiego 5A, 02-106 Warsaw, Poland
| | - Marta Modzelan
- Institute of Biochemistry and Biophysics PAS, Pawińskiego 5A, 02-106 Warsaw, Poland
| | - Elzbieta Kraszewska
- Institute of Biochemistry and Biophysics PAS, Pawińskiego 5A, 02-106 Warsaw, Poland
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83
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Targeting the alternative sigma factor RpoN to combat virulence in Pseudomonas aeruginosa. Sci Rep 2017; 7:12615. [PMID: 28974743 PMCID: PMC5626770 DOI: 10.1038/s41598-017-12667-y] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2017] [Accepted: 09/18/2017] [Indexed: 12/22/2022] Open
Abstract
Pseudomonas aeruginosa is a Gram-negative, opportunistic pathogen that infects immunocompromised and cystic fibrosis patients. Treatment is difficult due to antibiotic resistance, and new antimicrobials are needed to treat infections. The alternative sigma factor 54 (σ54, RpoN), regulates many virulence-associated genes. Thus, we evaluated inhibition of virulence in P. aeruginosa by a designed peptide (RpoN molecular roadblock, RpoN*) which binds specifically to RpoN consensus promoters. We expected that RpoN* binding to its consensus promoter sites would repress gene expression and thus virulence by blocking RpoN and/or other transcription factors. RpoN* reduced transcription of approximately 700 genes as determined by microarray analysis, including genes related to virulence. RpoN* expression significantly reduced motility, protease secretion, pyocyanin and pyoverdine production, rhamnolipid production, and biofilm formation. Given the effectiveness of RpoN* in vitro, we explored its effects in a Caenorhabditis elegans–P. aeruginosa infection model. Expression of RpoN* protected C. elegans in a paralytic killing assay, whereas worms succumbed to paralysis and death in its absence. In a slow killing assay, which mimics establishment and proliferation of an infection, C. elegans survival was prolonged when RpoN* was expressed. Thus, blocking RpoN consensus promoter sites is an effective strategy for abrogation of P. aeruginosa virulence.
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84
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Kang D, Kirienko NV. High-Throughput Genetic Screen Reveals that Early Attachment and Biofilm Formation Are Necessary for Full Pyoverdine Production by Pseudomonas aeruginosa. Front Microbiol 2017; 8:1707. [PMID: 28928729 PMCID: PMC5591869 DOI: 10.3389/fmicb.2017.01707] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2017] [Accepted: 08/23/2017] [Indexed: 01/14/2023] Open
Abstract
Pseudomonas aeruginosa is a re-emerging, multidrug-resistant, opportunistic pathogen that threatens the lives of immunocompromised patients, patients with cystic fibrosis, and those in critical care units. One of the most important virulence factors in this pathogen is the siderophore pyoverdine. Pyoverdine serves several critical roles during infection. Due to its extremely high affinity for ferric iron, pyoverdine gives the pathogen a significant advantage over the host in their competition for iron. In addition, pyoverdine can regulate the production of multiple bacterial virulence factors and perturb host mitochondrial homeostasis. Inhibition of pyoverdine biosynthesis decreases P. aeruginosa pathogenicity in multiple host models. To better understand the regulation of pyoverdine production, we developed a high-throughput genetic screen that uses the innate fluorescence of pyoverdine to identify genes necessary for its biosynthesis. A substantial number of hits showing severe impairment of pyoverdine production were in genes responsible for early attachment and biofilm formation. In addition to genetic disruption of biofilm, both physical and chemical perturbations also attenuated pyoverdine production. This regulatory relationship between pyoverdine and biofilm is particularly significant in the context of P. aeruginosa multidrug resistance, where the formation of biofilm is a key mechanism preventing access to antimicrobials and the immune system. Furthermore, we demonstrate that the biofilm inhibitor 2-amino-5,6-dimethylbenzimidazole effectively attenuates pyoverdine production and rescues Caenorhabditis elegans from P. aeruginosa-mediated pathogenesis. Our findings suggest that targeting biofilm formation in P. aeruginosa infections may have multiple therapeutic benefits and that employing an unbiased, systems biology-based approach may be useful for understanding the regulation of specific virulence factors and identifying novel anti-virulence therapeutics or new applications for existing therapies for P. aeruginosa infections.
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Affiliation(s)
- Donghoon Kang
- Department of Biosciences, Rice UniversityHouston, TX, United States
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85
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Kupferschmied P, Chai T, Flury P, Blom J, Smits THM, Maurhofer M, Keel C. Specific surface glycan decorations enable antimicrobial peptide resistance in plant-beneficial pseudomonads with insect-pathogenic properties. Environ Microbiol 2017; 18:4265-4281. [PMID: 27727519 DOI: 10.1111/1462-2920.13571] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2016] [Accepted: 10/06/2016] [Indexed: 11/29/2022]
Abstract
Some plant-beneficial pseudomonads can invade and kill pest insects in addition to their ability to protect plants from phytopathogens. We explored the genetic basis of O-polysaccharide (O-PS, O-antigen) biosynthesis in the representative insecticidal strains Pseudomonas protegens CHA0 and Pseudomonas chlororaphis PCL1391 and investigated its role in insect pathogenicity. Both strains produce two distinct forms of O-PS, but differ in the organization of their O-PS biosynthesis clusters. Biosynthesis of the dominant O-PS in both strains depends on a gene cluster similar to the O-specific antigen (OSA) cluster of Pseudomonas aeruginosa. In CHA0 and other P. protegens strains, the OSA cluster is extensively reduced and new clusters were acquired, resulting in high diversity of O-PS structures, possibly reflecting adaptation to different hosts. CHA0 mutants lacking the short OSA form of O-PS were significantly impaired in insect virulence in Galleria injection and Plutella feeding assays. CHA0, PCL1391, and other insecticidal pseudomonads exhibited high resistance to antimicrobial peptides, including cecropins that are central to insect immune defense. Resistance of both model strains depended on the dominant OSA-type O-PS. Our results suggest that O-antigen is essential for successful insect infection and illustrate, for the first time, its importance in resistance of Pseudomonas to antimicrobial peptides.
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Affiliation(s)
- Peter Kupferschmied
- Department of Fundamental Microbiology, University of Lausanne, Lausanne, Switzerland
| | - Tiancong Chai
- Department of Fundamental Microbiology, University of Lausanne, Lausanne, Switzerland
| | - Pascale Flury
- Plant Pathology, Institute of Integrative Biology, Swiss Federal Institute of Technology (ETH) Zurich, Zurich, Switzerland
| | - Jochen Blom
- Bioinformatics and Systems Biology, Justus-Liebig-University, Giessen, Germany
| | - Theo H M Smits
- Environmental Genomics and Systems Biology Research Group, Institute for Natural Resource Sciences, Zürich University of Applied Sciences, Wädenswil, Switzerland
| | - Monika Maurhofer
- Plant Pathology, Institute of Integrative Biology, Swiss Federal Institute of Technology (ETH) Zurich, Zurich, Switzerland
| | - Christoph Keel
- Department of Fundamental Microbiology, University of Lausanne, Lausanne, Switzerland
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86
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Beyond mouse cancer models: Three-dimensional human-relevant in vitro and non-mammalian in vivo models for photodynamic therapy. MUTATION RESEARCH-REVIEWS IN MUTATION RESEARCH 2017; 773:242-262. [DOI: 10.1016/j.mrrev.2016.09.002] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/29/2016] [Accepted: 09/09/2016] [Indexed: 02/08/2023]
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87
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Schulenburg H, Félix MA. The Natural Biotic Environment of Caenorhabditis elegans. Genetics 2017; 206:55-86. [PMID: 28476862 PMCID: PMC5419493 DOI: 10.1534/genetics.116.195511] [Citation(s) in RCA: 249] [Impact Index Per Article: 35.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2016] [Accepted: 02/28/2017] [Indexed: 01/05/2023] Open
Abstract
Organisms evolve in response to their natural environment. Consideration of natural ecological parameters are thus of key importance for our understanding of an organism's biology. Curiously, the natural ecology of the model species Caenorhabditis elegans has long been neglected, even though this nematode has become one of the most intensively studied models in biological research. This lack of interest changed ∼10 yr ago. Since then, an increasing number of studies have focused on the nematode's natural ecology. Yet many unknowns still remain. Here, we provide an overview of the currently available information on the natural environment of C. elegans We focus on the biotic environment, which is usually less predictable and thus can create high selective constraints that are likely to have had a strong impact on C. elegans evolution. This nematode is particularly abundant in microbe-rich environments, especially rotting plant matter such as decomposing fruits and stems. In this environment, it is part of a complex interaction network, which is particularly shaped by a species-rich microbial community. These microbes can be food, part of a beneficial gut microbiome, parasites and pathogens, and possibly competitors. C. elegans is additionally confronted with predators; it interacts with vector organisms that facilitate dispersal to new habitats, and also with competitors for similar food environments, including competitors from congeneric and also the same species. Full appreciation of this nematode's biology warrants further exploration of its natural environment and subsequent integration of this information into the well-established laboratory-based research approaches.
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Affiliation(s)
- Hinrich Schulenburg
- Zoological Institute, Christian-Albrechts Universitaet zu Kiel, 24098 Kiel, Germany
| | - Marie-Anne Félix
- Institut de Biologie de l'Ecole Normale Supérieure, Centre National de la Recherche Scientifique, Institut National de la Santé et de la Recherche Médicale, École Normale Supérieure, L'université de Recherche Paris Sciences et Lettres, 75005, France
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88
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Ali MK, Li X, Tang Q, Liu X, Chen F, Xiao J, Ali M, Chou SH, He J. Regulation of Inducible Potassium Transporter KdpFABC by the KdpD/KdpE Two-Component System in Mycobacterium smegmatis. Front Microbiol 2017; 8:570. [PMID: 28484428 PMCID: PMC5401905 DOI: 10.3389/fmicb.2017.00570] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2017] [Accepted: 03/20/2017] [Indexed: 12/28/2022] Open
Abstract
Kdp-ATPase is an inducible high affinity potassium uptake system that is widely distributed in bacteria, and is generally regulated by the KdpD/KdpE two-component system (TCS). In this study, conducted on Mycobacterium smegmatis, the kdpFABC (encoding Kdp-ATPase) expression was found to be affected by low concentration of K+, high concentrations of Na+, and/or [Formula: see text] of the medium. The KdpE was found to be a transcriptional regulator that bound to a specific 22-bp sequence in the promoter region of kdpFABC operon to positively regulate kdpFABC expression. The KdpE binding motif was highly conserved in the promoters of kdpFABC among the mycobacterial species. 5'-RACE data indicated a transcriptional start site (TSS) of the kdpFABC operon within the coding sequence of MSMEG_5391, which comprised a 120-bp long 5'-UTR and an open reading frame of the 87-bp kdpF gene. The kdpE deletion resulted in altered growth rate under normal and low K+ conditions. Furthermore, under K+ limiting conditions, a single transcript (kdpFABCDE) spanning kdpFABC and kdpDE operons was observed. This study provided the first insight into the regulation of kdpFABC operon by the KdpD/KdpE TCS in M. smegmatis.
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Affiliation(s)
- Maria K Ali
- State Key Laboratory of Agricultural Microbiology, College of Life Science and Technology, Huazhong Agricultural UniversityWuhan, China
| | - Xinfeng Li
- State Key Laboratory of Agricultural Microbiology, College of Life Science and Technology, Huazhong Agricultural UniversityWuhan, China
| | - Qing Tang
- State Key Laboratory of Agricultural Microbiology, College of Life Science and Technology, Huazhong Agricultural UniversityWuhan, China
| | - Xiaoyu Liu
- State Key Laboratory of Agricultural Microbiology, College of Life Science and Technology, Huazhong Agricultural UniversityWuhan, China
| | - Fang Chen
- State Key Laboratory of Agricultural Microbiology, College of Life Science and Technology, Huazhong Agricultural UniversityWuhan, China
| | - Jinfeng Xiao
- State Key Laboratory of Agricultural Microbiology, College of Life Science and Technology, Huazhong Agricultural UniversityWuhan, China
| | - Muhammad Ali
- State Key Laboratory of Agricultural Microbiology, College of Life Science and Technology, Huazhong Agricultural UniversityWuhan, China.,Biotechnology Program, Department of Environmental Sciences, COMSATS Institute of Information TechnologyAbbottabad, Pakistan
| | - Shan-Ho Chou
- Institute of Biochemistry and NCHU Agricultural Biotechnology Center, National Chung Hsing UniversityTaichung, Taiwan
| | - Jin He
- State Key Laboratory of Agricultural Microbiology, College of Life Science and Technology, Huazhong Agricultural UniversityWuhan, China
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89
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Bartell JA, Blazier AS, Yen P, Thøgersen JC, Jelsbak L, Goldberg JB, Papin JA. Reconstruction of the metabolic network of Pseudomonas aeruginosa to interrogate virulence factor synthesis. Nat Commun 2017; 8:14631. [PMID: 28266498 PMCID: PMC5344303 DOI: 10.1038/ncomms14631] [Citation(s) in RCA: 80] [Impact Index Per Article: 11.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2016] [Accepted: 01/18/2017] [Indexed: 01/13/2023] Open
Abstract
Virulence-linked pathways in opportunistic pathogens are putative therapeutic targets that may be associated with less potential for resistance than targets in growth-essential pathways. However, efficacy of virulence-linked targets may be affected by the contribution of virulence-related genes to metabolism. We evaluate the complex interrelationships between growth and virulence-linked pathways using a genome-scale metabolic network reconstruction of Pseudomonas aeruginosa strain PA14 and an updated, expanded reconstruction of P. aeruginosa strain PAO1. The PA14 reconstruction accounts for the activity of 112 virulence-linked genes and virulence factor synthesis pathways that produce 17 unique compounds. We integrate eight published genome-scale mutant screens to validate gene essentiality predictions in rich media, contextualize intra-screen discrepancies and evaluate virulence-linked gene distribution across essentiality datasets. Computational screening further elucidates interconnectivity between inhibition of virulence factor synthesis and growth. Successful validation of selected gene perturbations using PA14 transposon mutants demonstrates the utility of model-driven screening of therapeutic targets.
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Affiliation(s)
- Jennifer A. Bartell
- The Novo Nordisk Foundation Center for Biosustainability, Technical University of Denmark, 2970 Hørsholm, Denmark
- Biomedical Engineering, University of Virginia, Charlottesville, Virginia 22908, USA
| | - Anna S. Blazier
- Biomedical Engineering, University of Virginia, Charlottesville, Virginia 22908, USA
| | - Phillip Yen
- Biomedical Engineering, University of Virginia, Charlottesville, Virginia 22908, USA
| | - Juliane C. Thøgersen
- Department of Biotechnology and Biomedicine, Technical University of Denmark, 2800 Kgs. Lyngby, Denmark
| | - Lars Jelsbak
- Department of Biotechnology and Biomedicine, Technical University of Denmark, 2800 Kgs. Lyngby, Denmark
| | - Joanna B. Goldberg
- Department of Pediatrics, Division of Pulmonology, Allergy/Immunology, Cystic Fibrosis and Sleep, Children's Healthcare of Atlanta, Atlanta, Georgia 30322, USA
- Emory+Children's Center for Cystic Fibrosis Research, Emory University and Children's Healthcare of Atlanta, Atlanta, Georgia 30322, USA
| | - Jason A. Papin
- Biomedical Engineering, University of Virginia, Charlottesville, Virginia 22908, USA
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90
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Granato ET, Harrison F, Kümmerli R, Ross-Gillespie A. Do Bacterial "Virulence Factors" Always Increase Virulence? A Meta-Analysis of Pyoverdine Production in Pseudomonas aeruginosa As a Test Case. Front Microbiol 2016; 7:1952. [PMID: 28018298 PMCID: PMC5149528 DOI: 10.3389/fmicb.2016.01952] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2016] [Accepted: 11/21/2016] [Indexed: 01/05/2023] Open
Abstract
Bacterial traits that contribute to disease are termed “virulence factors” and there is much interest in therapeutic approaches that disrupt such traits. What remains less clear is whether a virulence factor identified as such in a particular context is also important in infections involving different host and pathogen types. Here, we address this question using a meta-analytic approach. We statistically analyzed the infection outcomes of 81 experiments associated with one well-studied virulence factor—pyoverdine, an iron-scavenging compound secreted by the opportunistic pathogen Pseudomonas aeruginosa. We found that this factor is consistently involved with virulence across different infection contexts. However, the magnitude of the effect of pyoverdine on virulence varied considerably. Moreover, its effect on virulence was relatively minor in many cases, suggesting that pyoverdine is not indispensable in infections. Our works supports theoretical models from ecology predicting that disease severity is multifactorial and context dependent, a fact that might complicate our efforts to identify the most important virulence factors. More generally, our study highlights how comparative approaches can be used to quantify the magnitude and general importance of virulence factors, key knowledge informing future anti-virulence treatment strategies.
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Affiliation(s)
- Elisa T Granato
- Department of Plant and Microbial Biology, University of Zurich Zurich, Switzerland
| | - Freya Harrison
- School of Life Sciences, University of Warwick Coventry, UK
| | - Rolf Kümmerli
- Department of Plant and Microbial Biology, University of Zurich Zurich, Switzerland
| | - Adin Ross-Gillespie
- Department of Plant and Microbial Biology, University of ZurichZurich, Switzerland; SIB Swiss Institute of BioinformaticsLausanne, Switzerland
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91
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Tan H, Zhang L, Zhao Q, Chen R, Liu C, Weng Y, Peng Q, Bai F, Cheng Z, Jin S, Wu W, Jin Y. DeaD contributes to Pseudomonas aeruginosa virulence in a mouse acute pneumonia model. FEMS Microbiol Lett 2016; 363:fnw227. [PMID: 27682417 DOI: 10.1093/femsle/fnw227] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/27/2016] [Indexed: 02/05/2023] Open
Abstract
DExD/H box RNA helicases play essential roles in various biological processes in prokaryotes and eukaryotes. By screening Pseudomonas aeruginosa strains with mutations in various DExD/H box helicase genes, we identified that deaD was required for bacterial cytotoxicity and virulence in a mouse acute pneumonia model. Compared to a wild-type strain and its complementation strain, the deaD mutant induced less production of proinflammatory cytokines, neutrophil infiltration and lung damage during infection. We further found that the RNA helicase activity of DeaD was required for the expression of type III secretion system (T3SS) genes. Overexpression of ExsA, a master activator of the T3SS, restored the expression of T3SS genes as well as the virulence of the deaD mutant, suggesting that the attenuated virulence of the deaD mutant was mainly due to the defective T3SS. Overall, our results reveal a role of DeaD in the virulence of P. aeruginosa.
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Affiliation(s)
- Hao Tan
- State Key Laboratory of Medicinal Chemical Biology, Key Laboratory of Molecular Microbiology and Technology of the Ministry of Education, Department of Microbiology, College of Life Sciences, Nankai University, Tianjin 300071, China
| | - Lu Zhang
- State Key Laboratory of Medicinal Chemical Biology, Key Laboratory of Molecular Microbiology and Technology of the Ministry of Education, Department of Microbiology, College of Life Sciences, Nankai University, Tianjin 300071, China
| | - Qiang Zhao
- College of Life Sciences, Nankai University, Tianjin 300071, China
| | - Ronghao Chen
- State Key Laboratory of Medicinal Chemical Biology, Key Laboratory of Molecular Microbiology and Technology of the Ministry of Education, Department of Microbiology, College of Life Sciences, Nankai University, Tianjin 300071, China
| | - Chang Liu
- State Key Laboratory of Medicinal Chemical Biology, Key Laboratory of Molecular Microbiology and Technology of the Ministry of Education, Department of Microbiology, College of Life Sciences, Nankai University, Tianjin 300071, China
| | - Yuding Weng
- State Key Laboratory of Medicinal Chemical Biology, Key Laboratory of Molecular Microbiology and Technology of the Ministry of Education, Department of Microbiology, College of Life Sciences, Nankai University, Tianjin 300071, China
| | - Qianqian Peng
- State Key Laboratory of Medicinal Chemical Biology, Key Laboratory of Molecular Microbiology and Technology of the Ministry of Education, Department of Microbiology, College of Life Sciences, Nankai University, Tianjin 300071, China
| | - Fang Bai
- State Key Laboratory of Medicinal Chemical Biology, College of Pharmacyand Life Sciences, and Tianjin Key Laboratory of Molecular Drug Research, Nankai University, Tianjin 300071, China
| | - Zhihui Cheng
- State Key Laboratory of Medicinal Chemical Biology, Key Laboratory of Molecular Microbiology and Technology of the Ministry of Education, Department of Microbiology, College of Life Sciences, Nankai University, Tianjin 300071, China
| | - Shouguang Jin
- Department of Molecular Genetics and Microbiology, College of Medicine, University of Florida, Gainesville, FL 32610, USA
| | - Weihui Wu
- State Key Laboratory of Medicinal Chemical Biology, Key Laboratory of Molecular Microbiology and Technology of the Ministry of Education, Department of Microbiology, College of Life Sciences, Nankai University, Tianjin 300071, China
| | - Yongxin Jin
- State Key Laboratory of Medicinal Chemical Biology, Key Laboratory of Molecular Microbiology and Technology of the Ministry of Education, Department of Microbiology, College of Life Sciences, Nankai University, Tianjin 300071, China
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92
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Mina EG, Marques CNH. Interaction of Staphylococcus aureus persister cells with the host when in a persister state and following awakening. Sci Rep 2016; 6:31342. [PMID: 27506163 PMCID: PMC4979210 DOI: 10.1038/srep31342] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2016] [Accepted: 07/18/2016] [Indexed: 12/18/2022] Open
Abstract
Persister cells, a tolerant cell sub-population, are commonly associated with chronic and recurrent infections. However, little is known about their ability to actually initiate or establish an infection, become virulent and cause pathogenicity within a host. Here we investigated whether Staphylococcus aureus persister cells initiate an infection and are recognized by macrophages, while in a persister cell status, and upon awakening due to exposure to cis-2-decenoic acid (cis-DA). Our results show that S. aureus persister cells are not able to initiate infections in A. thaliana and present significantly reduced virulence towards C. elegans compared to total populations. In contrast, awakened S. aureus persister cells are able to initiate infections in A. thaliana and in C. elegans albeit, with lower mortality than total population. Furthermore, exposure of S. aureus persister cells to cis-DA led to a loss of tolerance to ciprofloxacin, and an increase of the bacterial fluorescence to levels found in total population. In addition, macrophage engulfment of persister cells was significantly lower than engulfment of total population, both before and following awakening. Overall our findings indicate that upon awakening of a persister population the cells regain their ability to infect hosts despite the absence of an increased immune response.
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Affiliation(s)
- Elin G Mina
- Department of Biological Sciences, Binghamton University, Binghamton, NY, 13902, USA.,Binghamton Biofilm Research Center (BBRC), Binghamton University, Binghamton, NY, 13902, USA
| | - Cláudia N H Marques
- Department of Biological Sciences, Binghamton University, Binghamton, NY, 13902, USA.,Binghamton Biofilm Research Center (BBRC), Binghamton University, Binghamton, NY, 13902, USA
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93
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Disruption of Transporters Affiliated with Enantio-Pyochelin Biosynthesis Gene Cluster of Pseudomonas protegens Pf-5 Has Pleiotropic Effects. PLoS One 2016; 11:e0159884. [PMID: 27442435 PMCID: PMC4956303 DOI: 10.1371/journal.pone.0159884] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2016] [Accepted: 07/08/2016] [Indexed: 12/22/2022] Open
Abstract
Pseudomonas protegens Pf-5 (formerly Pseudomonas fluorescens) is a biocontrol bacterium that produces the siderophore enantio-pyochelin under conditions of iron starvation in a process that is often accompanied by the secretion of its biosynthesis intermediates, salicylic acid and dihydroaeruginoic acid. In this study, we investigated whether several transporters that are encoded by genes within or adjacent to the enantio-pyochelin biosynthetic cluster, serve as efflux systems for enantio-pyochelin and/or its intermediates. In addition, we determined whether these transporters have broad substrates range specificity using a Phenotype Microarray system. Intriguingly, knockouts of the pchH and fetF transporter genes resulted in mutant strains that secrete higher levels of enantio-pyochelin as well as its intermediates salicylic acid and dihydroaeruginoic acid. Analyses of these mutants did not indicate significant change in transcription of biosynthetic genes involved in enantio-pyochelin production. In contrast, the deletion mutant of PFL_3504 resulted in reduced transcription of the biosynthetic genes as well as decreased dihydroaeruginoic acid concentrations in the culture supernatant, which could either point to regulation of gene expression by the transporter or its role in dihydroaeruginoic acid transport. Disruption of each of the transporters resulted in altered stress and/or chemical resistance profile of Pf-5, which may reflect that these transporters could have specificity for rather a broad range of substrates.
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94
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Ali M, Sun Y, Xie L, Yu H, Bashir A, Li L. The Pathogenicity of Pseudomonas syringae MB03 against Caenorhabditis elegans and the Transcriptional Response of Nematicidal Genes upon Different Nutritional Conditions. Front Microbiol 2016; 7:805. [PMID: 27303387 PMCID: PMC4884745 DOI: 10.3389/fmicb.2016.00805] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2016] [Accepted: 05/12/2016] [Indexed: 12/22/2022] Open
Abstract
Different species of the Pseudomonas genus have been reported for their pathogenic potential against animal cells. However, the pathogenicity of Pseudomonas syringae against Caenorhabditis elegans has never been reported. In this study, the interaction of P. syringae MB03 with C. elegans was studied. Different bioassays such as killing assay, lawn leaving assay, food preference assay, L4 growth assay and newly developed “secretion assay” were performed to evaluate the pathogenic potential of P. syringae on different growth media. The results of the killing assay showed that P. syringae MB03 was able to kill C. elegans under specific conditions, as the interaction between the host and the pathogen varied from non-pathogenic (assay on NGM medium) to pathogenic (assay on PG medium). The lawn leaving assay and the food preference assay illustrated that C. elegans identified P. syringae MB03 as a pathogen when assays were performed on PG medium. Green fluorescent protein was used as the reporter protein to study gut colonization by P. syringae MB03. Our results suggested that MB03 has the ability to colonize the gut of C. elegans. Furthermore, to probe the role of selected virulence determinants, qRT-PCR was used. The genes for pyoverdine, phoQ/phoP, phoR/phoB, and flagella were up regulated during the interaction of P. syringae MB03 and C. elegans on PG medium. Other than these, the genes for some proteases, such as pepP, clpA, and clpS, were also up regulated. On the other hand, kdpD and kdpB were down regulated more than threefold in the NGM – C. elegans interaction model. The deletion of the kdpD and kdpE genes altered the pathogenicity of the bacterial strain against C. elegans. Overall, our results suggested that the killing of C. elegans by P. syringae requires a prolonged interaction between the host and pathogen in an agar-based assay. Moreover, it seemed that some toxic metabolites were secreted by the bacterial strain that were sensed by C. elegans. Previously, it was believed that P. syringae could not damage animal cells. However, this study provides evidence of the pathogenic behavior of P. syringae against C. elegans.
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Affiliation(s)
- Muhammad Ali
- State Key Laboratory of Agricultural Microbiology, Huazhong Agricultural UniversityWuhan, China; Biotechnology Program, Department of Environmental Sciences, COMSATS Institute of Information TechnologyAbbottabad, Pakistan
| | - Yu Sun
- State Key Laboratory of Agricultural Microbiology, Huazhong Agricultural University Wuhan, China
| | - Li Xie
- State Key Laboratory of Agricultural Microbiology, Huazhong Agricultural University Wuhan, China
| | - Huafu Yu
- State Key Laboratory of Agricultural Microbiology, Huazhong Agricultural University Wuhan, China
| | - Anum Bashir
- State Key Laboratory of Agricultural Microbiology, Huazhong Agricultural University Wuhan, China
| | - Lin Li
- State Key Laboratory of Agricultural Microbiology, Huazhong Agricultural University Wuhan, China
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95
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Hwang S, Kim CY, Ji SG, Go J, Kim H, Yang S, Kim HJ, Cho A, Yoon SS, Lee I. Network-assisted investigation of virulence and antibiotic-resistance systems in Pseudomonas aeruginosa. Sci Rep 2016; 6:26223. [PMID: 27194047 PMCID: PMC4872156 DOI: 10.1038/srep26223] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2015] [Accepted: 04/29/2016] [Indexed: 12/21/2022] Open
Abstract
Pseudomonas aeruginosa is a Gram-negative bacterium of clinical significance. Although the genome of PAO1, a prototype strain of P. aeruginosa, has been extensively studied, approximately one-third of the functional genome remains unknown. With the emergence of antibiotic-resistant strains of P. aeruginosa, there is an urgent need to develop novel antibiotic and anti-virulence strategies, which may be facilitated by an approach that explores P. aeruginosa gene function in systems-level models. Here, we present a genome-wide functional network of P. aeruginosa genes, PseudomonasNet, which covers 98% of the coding genome, and a companion web server to generate functional hypotheses using various network-search algorithms. We demonstrate that PseudomonasNet-assisted predictions can effectively identify novel genes involved in virulence and antibiotic resistance. Moreover, an antibiotic-resistance network based on PseudomonasNet reveals that P. aeruginosa has common modular genetic organisations that confer increased or decreased resistance to diverse antibiotics, which accounts for the pervasiveness of cross-resistance across multiple drugs. The same network also suggests that P. aeruginosa has developed mechanism of trade-off in resistance across drugs by altering genetic interactions. Taken together, these results clearly demonstrate the usefulness of a genome-scale functional network to investigate pathogenic systems in P. aeruginosa.
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Affiliation(s)
- Sohyun Hwang
- Department of Biotechnology, College of Life Science and Biotechnology, Yonsei University, Seoul, 120-749, Korea.,Center for Systems and Synthetic Biology, University of Texas at Austin, Austin, TX 78712, USA
| | - Chan Yeong Kim
- Department of Biotechnology, College of Life Science and Biotechnology, Yonsei University, Seoul, 120-749, Korea
| | - Sun-Gou Ji
- Department of Biotechnology, College of Life Science and Biotechnology, Yonsei University, Seoul, 120-749, Korea
| | - Junhyeok Go
- Department of Microbiology and Immunology, Brain Korea 21 PLUS Project for Medical Science, Yonsei University College of Medicine, Seoul, 120-749, Korea
| | - Hanhae Kim
- Department of Biotechnology, College of Life Science and Biotechnology, Yonsei University, Seoul, 120-749, Korea
| | - Sunmo Yang
- Department of Biotechnology, College of Life Science and Biotechnology, Yonsei University, Seoul, 120-749, Korea
| | - Hye Jin Kim
- Department of Microbiology and Immunology, Brain Korea 21 PLUS Project for Medical Science, Yonsei University College of Medicine, Seoul, 120-749, Korea
| | - Ara Cho
- Department of Biotechnology, College of Life Science and Biotechnology, Yonsei University, Seoul, 120-749, Korea
| | - Sang Sun Yoon
- Department of Microbiology and Immunology, Brain Korea 21 PLUS Project for Medical Science, Yonsei University College of Medicine, Seoul, 120-749, Korea
| | - Insuk Lee
- Department of Biotechnology, College of Life Science and Biotechnology, Yonsei University, Seoul, 120-749, Korea
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96
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Guo Q, Wei Y, Xia B, Jin Y, Liu C, Pan X, Shi J, Zhu F, Li J, Qian L, Liu X, Cheng Z, Jin S, Lin J, Wu W. Identification of a small molecule that simultaneously suppresses virulence and antibiotic resistance of Pseudomonas aeruginosa. Sci Rep 2016; 6:19141. [PMID: 26751736 PMCID: PMC4707474 DOI: 10.1038/srep19141] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2015] [Accepted: 12/07/2015] [Indexed: 12/20/2022] Open
Abstract
The rising antibiotic resistance of bacteria imposes a severe threat on human health. Inhibition of bacterial virulence is an alternative approach to develop new antimicrobials. Molecules targeting antibiotic resistant enzymes have been used in combination with cognate antibiotics. It might be ideal that a molecule can simultaneously suppress virulence factors and antibiotic resistance. Here we combined genetic and computer-aided inhibitor screening to search for such molecules against the bacterial pathogen Pseudomonas aeruginosa. To identify target proteins that control both virulence and antibiotic resistance, we screened for mutants with defective cytotoxicity and biofilm formation from 93 transposon insertion mutants previously reported with increased antibiotic susceptibility. A pyrD mutant displayed defects in cytotoxicity, biofilm formation, quorum sensing and virulence in an acute mouse pneumonia model. Next, we employed a computer-aided screening to identify potential inhibitors of the PyrD protein, a dihydroorotate dehydrogenase (DHODase) involved in pyrimidine biosynthesis. One of the predicted inhibitors was able to suppress the enzymatic activity of PyrD as well as bacterial cytotoxicity, biofilm formation and antibiotic resistance. A single administration of the compound reduced the bacterial colonization in the acute mouse pneumonia model. Therefore, we have developed a strategy to identify novel treatment targets and antimicrobial molecules.
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Affiliation(s)
- Qiaoyun Guo
- State Key Laboratory of Medicinal Chemical Biology, Key Laboratory of Molecular Microbiology and Technology of the Ministry of Education, Department of Microbiology, College of Life Sciences, Nankai University, Tianjin 300071, China
| | - Yu Wei
- State Key Laboratory of Medicinal Chemical Biology and College of Pharmacy, Nankai University, Tianjin 300071, China
| | - Bin Xia
- State Key Laboratory of Medicinal Chemical Biology, Key Laboratory of Molecular Microbiology and Technology of the Ministry of Education, Department of Microbiology, College of Life Sciences, Nankai University, Tianjin 300071, China
| | - Yongxin Jin
- State Key Laboratory of Medicinal Chemical Biology, Key Laboratory of Molecular Microbiology and Technology of the Ministry of Education, Department of Microbiology, College of Life Sciences, Nankai University, Tianjin 300071, China
| | - Chang Liu
- State Key Laboratory of Medicinal Chemical Biology, Key Laboratory of Molecular Microbiology and Technology of the Ministry of Education, Department of Microbiology, College of Life Sciences, Nankai University, Tianjin 300071, China
| | - Xiaolei Pan
- State Key Laboratory of Medicinal Chemical Biology, Key Laboratory of Molecular Microbiology and Technology of the Ministry of Education, Department of Microbiology, College of Life Sciences, Nankai University, Tianjin 300071, China
| | - Jing Shi
- State Key Laboratory of Medicinal Chemical Biology, Key Laboratory of Molecular Microbiology and Technology of the Ministry of Education, Department of Microbiology, College of Life Sciences, Nankai University, Tianjin 300071, China
| | - Feng Zhu
- State Key Laboratory of Medicinal Chemical Biology, Key Laboratory of Molecular Microbiology and Technology of the Ministry of Education, Department of Microbiology, College of Life Sciences, Nankai University, Tianjin 300071, China
| | - Jinlong Li
- State Key Laboratory of Medicinal Chemical Biology and College of Pharmacy, Nankai University, Tianjin 300071, China
| | - Lei Qian
- State Key Laboratory of Medicinal Chemical Biology, College of Life Sciences, Nankai University, Tianjin, 300071, China
| | - Xinqi Liu
- State Key Laboratory of Medicinal Chemical Biology, College of Life Sciences, Nankai University, Tianjin, 300071, China
| | - Zhihui Cheng
- State Key Laboratory of Medicinal Chemical Biology, Key Laboratory of Molecular Microbiology and Technology of the Ministry of Education, Department of Microbiology, College of Life Sciences, Nankai University, Tianjin 300071, China
| | - Shouguang Jin
- State Key Laboratory of Medicinal Chemical Biology, Key Laboratory of Molecular Microbiology and Technology of the Ministry of Education, Department of Microbiology, College of Life Sciences, Nankai University, Tianjin 300071, China
- Department of Molecular Genetics and Microbiology, College of Medicine, University of Florida, Gainesville, FL 32610, USA
| | - Jianping Lin
- State Key Laboratory of Medicinal Chemical Biology, Key Laboratory of Molecular Microbiology and Technology of the Ministry of Education, Department of Microbiology, College of Life Sciences, Nankai University, Tianjin 300071, China
- State Key Laboratory of Medicinal Chemical Biology and College of Pharmacy, Nankai University, Tianjin 300071, China
| | - Weihui Wu
- State Key Laboratory of Medicinal Chemical Biology, Key Laboratory of Molecular Microbiology and Technology of the Ministry of Education, Department of Microbiology, College of Life Sciences, Nankai University, Tianjin 300071, China
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97
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Silva-Valenzuela CA, Molina-Quiroz RC, Desai P, Valenzuela C, Porwollik S, Zhao M, Hoffman RM, Andrews-Polymenis H, Contreras I, Santiviago CA, McClelland M. Analysis of Two Complementary Single-Gene Deletion Mutant Libraries of Salmonella Typhimurium in Intraperitoneal Infection of BALB/c Mice. Front Microbiol 2016; 6:1455. [PMID: 26779130 PMCID: PMC4700939 DOI: 10.3389/fmicb.2015.01455] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2015] [Accepted: 12/04/2015] [Indexed: 01/20/2023] Open
Abstract
Two pools of individual single gene deletion (SGD) mutants of S. Typhimurium 14028s encompassing deletions of 3,923 annotated non-essential ORFs and sRNAs were screened by intraperitoneal (IP) injection in BALB/c mice followed by recovery from spleen and liver 2 days post infection. The relative abundance of each mutant was measured by microarray hybridization. The two mutant libraries differed in the orientation of the antibiotic resistance cassettes (either sense-oriented Kan(R), SGD-K, or antisense-oriented Cam(R), SGD-C). Consistent systemic colonization defects were observed in both libraries and both organs for hundreds of mutants of genes previously reported to be important after IP injection in this animal model, and for about 100 new candidate genes required for systemic colonization. Four mutants with a range of apparent fitness defects were confirmed using competitive infections with the wild-type parental strain: ΔSTM0286, ΔSTM0551, ΔSTM2363, and ΔSTM3356. Two mutants, ΔSTM0286 and ΔSTM2363, were then complemented in trans with a plasmid encoding an intact copy of the corresponding wild-type gene, and regained the ability to fully colonize BALB/c mice systemically. These results suggest the presence of many more undiscovered Salmonella genes with phenotypes in IP infection of BALB/c mice, and validate the libraries for application to other systems.
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Affiliation(s)
- Cecilia A. Silva-Valenzuela
- Department of Microbiology and Molecular Genetics, University of California, IrvineIrvine, CA, USA
- Departamento de Bioquímica y Biología Molecular, Facultad de Ciencias Químicas y Farmacéuticas, Universidad de ChileSantiago, Chile
| | - Roberto C. Molina-Quiroz
- Departamento de Bioquímica y Biología Molecular, Facultad de Ciencias Químicas y Farmacéuticas, Universidad de ChileSantiago, Chile
- Center for Adaptation Genetics and Drug Resistance, Tufts UniversityBoston, MA, USA
| | - Prerak Desai
- Department of Microbiology and Molecular Genetics, University of California, IrvineIrvine, CA, USA
| | - Camila Valenzuela
- Departamento de Bioquímica y Biología Molecular, Facultad de Ciencias Químicas y Farmacéuticas, Universidad de ChileSantiago, Chile
| | - Steffen Porwollik
- Department of Microbiology and Molecular Genetics, University of California, IrvineIrvine, CA, USA
| | | | - Robert M. Hoffman
- Anticancer Inc.San Diego, CA, USA
- Department of Surgery, UC San Diego School of Medicine, University of California, San DiegoSan Diego, CA, USA
| | - Helene Andrews-Polymenis
- Department of Microbial Pathogenesis and Immunology, Texas A&M UniversityCollege Station, TX, USA
| | - Inés Contreras
- Departamento de Bioquímica y Biología Molecular, Facultad de Ciencias Químicas y Farmacéuticas, Universidad de ChileSantiago, Chile
| | - Carlos A. Santiviago
- Departamento de Bioquímica y Biología Molecular, Facultad de Ciencias Químicas y Farmacéuticas, Universidad de ChileSantiago, Chile
| | - Michael McClelland
- Department of Microbiology and Molecular Genetics, University of California, IrvineIrvine, CA, USA
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98
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Control of Biofilms with the Fatty Acid Signaling Molecule cis-2-Decenoic Acid. Pharmaceuticals (Basel) 2015; 8:816-35. [PMID: 26610524 PMCID: PMC4695811 DOI: 10.3390/ph8040816] [Citation(s) in RCA: 64] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2015] [Revised: 11/11/2015] [Accepted: 11/18/2015] [Indexed: 12/26/2022] Open
Abstract
Biofilms are complex communities of microorganisms in organized structures attached to surfaces. Importantly, biofilms are a major cause of bacterial infections in humans, and remain one of the most significant challenges to modern medical practice. Unfortunately, conventional therapies have shown to be inadequate in the treatment of most chronic biofilm infections based on the extraordinary innate tolerance of biofilms to antibiotics. Antagonists of quorum sensing signaling molecules have been used as means to control biofilms. QS and other cell-cell communication molecules are able to revert biofilm tolerance, prevent biofilm formation and disrupt fully developed biofilms, albeit with restricted effectiveness. Recently however, it has been demonstrated that Pseudomonas aeruginosa produces a small messenger molecule cis-2-decenoic acid (cis-DA) that shows significant promise as an effective adjunctive to antimicrobial treatment of biofilms. This molecule is responsible for induction of the native biofilm dispersion response in a range of Gram-negative and Gram-positive bacteria and in yeast, and has been shown to reverse persistence, increase microbial metabolic activity and significantly enhance the cidal effects of conventional antimicrobial agents. In this manuscript, the use of cis-2-decenoic acid as a novel agent for biofilm control is discussed. Stimulating the biofilm dispersion response as a novel antimicrobial strategy holds significant promise for enhanced treatment of infections and in the prevention of biofilm formation.
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99
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Tedesco P, Visone M, Parrilli E, Tutino ML, Perrin E, Maida I, Fani R, Ballestriero F, Santos R, Pinilla C, Di Schiavi E, Tegos G, de Pascale D. Investigating the Role of the Host Multidrug Resistance Associated Protein Transporter Family in Burkholderia cepacia Complex Pathogenicity Using a Caenorhabditis elegans Infection Model. PLoS One 2015; 10:e0142883. [PMID: 26587842 PMCID: PMC4654563 DOI: 10.1371/journal.pone.0142883] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2015] [Accepted: 10/28/2015] [Indexed: 11/24/2022] Open
Abstract
This study investigated the relationship between host efflux system of the non-vertebrate nematode Caenorhabditis elegans and Burkholderia cepacia complex (Bcc) strain virulence. This is the first comprehensive effort to profile host-transporters within the context of Bcc infection. With this aim, two different toxicity tests were performed: a slow killing assay that monitors mortality of the host by intestinal colonization and a fast killing assay that assesses production of toxins. A Virulence Ranking scheme was defined, that expressed the toxicity of the Bcc panel members, based on the percentage of surviving worms. According to this ranking the 18 Bcc strains were divided in 4 distinct groups. Only the Cystic Fibrosis isolated strains possessed profound nematode killing ability to accumulate in worms’ intestines. For the transporter analysis a complete set of isogenic nematode single Multidrug Resistance associated Protein (MRP) efflux mutants and a number of efflux inhibitors were interrogated in the host toxicity assays. The Bcc pathogenicity profile of the 7 isogenic C. elegans MRP knock-out strains functionality was classified in two distinct groups. Disabling host transporters enhanced nematode mortality more than 50% in 5 out of 7 mutants when compared to wild type. In particular mrp-2 was the most susceptible phenotype with increased mortality for 13 out 18 Bcc strains, whereas mrp-3 and mrp-4 knock-outs had lower mortality rates, suggesting a different role in toxin-substrate recognition. The use of MRP efflux inhibitors in the assays resulted in substantially increased (>40% on average) mortality of wild-type worms.
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Affiliation(s)
- Pietro Tedesco
- Institute of Protein Biochemistry, National Research Council, Via P. Castellino 111, I-80131, Naples, Italy
- Department of Chemical Sciences and School of Biotechnological Sciences, University of Naples Federico II, Via Cintia, I-80126, Naples, Italy
| | - Marco Visone
- Institute of Protein Biochemistry, National Research Council, Via P. Castellino 111, I-80131, Naples, Italy
| | - Ermenegilda Parrilli
- Department of Chemical Sciences and School of Biotechnological Sciences, University of Naples Federico II, Via Cintia, I-80126, Naples, Italy
| | - Maria Luisa Tutino
- Department of Chemical Sciences and School of Biotechnological Sciences, University of Naples Federico II, Via Cintia, I-80126, Naples, Italy
| | - Elena Perrin
- Laboratory of Microbial and Molecular Evolution, Department of Biology, University of Florence, Via Madonna del Piano, I-50019, Sesto Fiorentino, Florence, Italy
| | - Isabel Maida
- Laboratory of Microbial and Molecular Evolution, Department of Biology, University of Florence, Via Madonna del Piano, I-50019, Sesto Fiorentino, Florence, Italy
| | - Renato Fani
- Laboratory of Microbial and Molecular Evolution, Department of Biology, University of Florence, Via Madonna del Piano, I-50019, Sesto Fiorentino, Florence, Italy
| | - Francesco Ballestriero
- School of Biotechnology and Biomolecular Sciences and Centre for Marine Bio-Innovation, University of New South Wales, Sydney, 2052, New South Wales, Australia
| | - Radleigh Santos
- Torrey Pines Institute of Molecular Studies, Port St. Lucie, FL, United States of America, and San Diego, CA, United States of America
| | - Clemencia Pinilla
- Torrey Pines Institute of Molecular Studies, Port St. Lucie, FL, United States of America, and San Diego, CA, United States of America
| | - Elia Di Schiavi
- Institute of Bioscience and BioResources, National Research Council, via P. Castellino 111, I-80131, Naples, Italy
- Institute of Genetics and Biophysics, National Research Council, via P. Castellino 111, I-80131, Naples, Italy
| | - George Tegos
- Torrey Pines Institute of Molecular Studies, Port St. Lucie, FL, United States of America, and San Diego, CA, United States of America
- Wellman Centre for Photomedicine, Massachusetts General Hospital, Boston, MA, United States of America
- Department of Dermatology, Harvard Medical School, Boston, MA, United States of America
- * E-mail: (DdP); (GT)
| | - Donatella de Pascale
- Institute of Protein Biochemistry, National Research Council, Via P. Castellino 111, I-80131, Naples, Italy
- * E-mail: (DdP); (GT)
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100
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Zrieq R, Sana TG, Vergin S, Garvis S, Volfson I, Bleves S, Voulhoux R, Hegemann JH. Genome-wide Screen of Pseudomonas aeruginosa in Saccharomyces cerevisiae Identifies New Virulence Factors. Front Cell Infect Microbiol 2015; 5:81. [PMID: 26636043 PMCID: PMC4644809 DOI: 10.3389/fcimb.2015.00081] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2015] [Accepted: 10/31/2015] [Indexed: 01/12/2023] Open
Abstract
Pseudomonas aeruginosa is a human opportunistic pathogen that causes mortality in cystic fibrosis and immunocompromised patients. While many virulence factors of this pathogen have already been identified, several remain to be discovered. In this respect we set an unprecedented genome-wide screen of a P. aeruginosa expression library based on a yeast growth phenotype. Fifty-one candidates were selected in athree-round screening process. The robustness of the screen was validated by the selection of three well known secreted proteins including one demonstrated virulence factor, the protease LepA. Further in silico sorting of the 51 candidates highlighted three potential new Pseudomonas effector candidates (Pec). By testing the cytotoxicity of wild type P. aeruginosa vs. pec mutants toward macrophages and the virulence in the Caenorhabditis elegans model, we demonstrated that the three selected Pecs are novel virulence factors of P. aeruginosa. Additional cellular localization experiments in the host revealed specific localization for Pec1 and Pec2 that could inform about their respective functions.
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Affiliation(s)
- Rafat Zrieq
- Institut für Funktionelle Genomforschung der Mikroorganismen, Heinrich-Heine-Universität Düsseldorf Düsseldorf, Germany
| | - Thibault G Sana
- Laboratoire d'Ingénierie des Systèmes Macromoléculaires (UMR7255), Institut de Microbiologie de la Méditerranée, Centre National de la Recherche Scientifique, Aix-Marseille Université Marseille, France
| | - Sandra Vergin
- Institut für Funktionelle Genomforschung der Mikroorganismen, Heinrich-Heine-Universität Düsseldorf Düsseldorf, Germany
| | - Steve Garvis
- Laboratoire d'Ingénierie des Systèmes Macromoléculaires (UMR7255), Institut de Microbiologie de la Méditerranée, Centre National de la Recherche Scientifique, Aix-Marseille Université Marseille, France
| | - Irina Volfson
- Institut für Funktionelle Genomforschung der Mikroorganismen, Heinrich-Heine-Universität Düsseldorf Düsseldorf, Germany
| | - Sophie Bleves
- Laboratoire d'Ingénierie des Systèmes Macromoléculaires (UMR7255), Institut de Microbiologie de la Méditerranée, Centre National de la Recherche Scientifique, Aix-Marseille Université Marseille, France
| | - Romé Voulhoux
- Laboratoire d'Ingénierie des Systèmes Macromoléculaires (UMR7255), Institut de Microbiologie de la Méditerranée, Centre National de la Recherche Scientifique, Aix-Marseille Université Marseille, France
| | - Johannes H Hegemann
- Institut für Funktionelle Genomforschung der Mikroorganismen, Heinrich-Heine-Universität Düsseldorf Düsseldorf, Germany
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