1
|
Nazeih SI, Ali MAM, Halim ASA, Al-Lawati H, Abbas HA, Al-Zharani M, Boufahja F, Alghamdi MA, Hegazy WAH, Seleem NM. Relocating Glyceryl Trinitrate as an Anti-Virulence Agent against Pseudomonas aeruginosa and Serratia marcescens: Insights from Molecular and In Vivo Investigations. Microorganisms 2023; 11:2420. [PMID: 37894078 PMCID: PMC10609227 DOI: 10.3390/microorganisms11102420] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2023] [Revised: 09/23/2023] [Accepted: 09/24/2023] [Indexed: 10/29/2023] Open
Abstract
The problem of antibiotic resistance is a global critical public health concern. In light of the threat of returning to the pre-antibiotic era, new alternative approaches are required such as quorum-sensing (QS) disruption and virulence inhibition, both of which apply no discernible selective pressure on bacteria, therefore mitigating the potential for the development of resistant strains. Bearing in mind the significant role of QS in orchestrating bacterial virulence, disrupting QS becomes essential for effectively diminishing bacterial virulence. This study aimed to assess the potential use of sub-inhibitory concentration (0.25 mg/mL) of glyceryl trinitrate (GTN) to inhibit virulence in Serratia marcescens and Pseudomonas aeruginosa. GTN could decrease the expression of virulence genes in both tested bacteria in a significant manner. Histopathological study revealed the ability of GTN to alleviate the congestion in hepatic and renal tissues of infected mice and to reduce bacterial and leukocyte infiltration. This study recommends the use of topical GTN to treat topical infection caused by P. aeruginosa and S. marcescens in combination with antibiotics.
Collapse
Affiliation(s)
- Shaimaa I. Nazeih
- Department of Microbiology and Immunology, Faculty of Pharmacy, Zagazig University, Zagazig 44519, Egypt; (S.I.N.); (H.A.A.); (N.M.S.)
| | - Mohamed A. M. Ali
- Department of Biology, College of Science, Imam Mohammad Ibn Saud Islamic University (IMSIU), Riyadh 11623, Saudi Arabia; (M.A.M.A.); (F.B.)
- Department of Biochemistry, Faculty of Science, Ain Shams University, Abbassia, Cairo 11566, Egypt;
| | - Alyaa S. Abdel Halim
- Department of Biochemistry, Faculty of Science, Ain Shams University, Abbassia, Cairo 11566, Egypt;
| | - Hanan Al-Lawati
- Pharmacy Program, Department of Pharmaceutics, Oman College of Health Sciences, Muscat 113, Oman;
| | - Hisham A. Abbas
- Department of Microbiology and Immunology, Faculty of Pharmacy, Zagazig University, Zagazig 44519, Egypt; (S.I.N.); (H.A.A.); (N.M.S.)
| | - Mohammed Al-Zharani
- Department of Biology, College of Science, Imam Mohammad Ibn Saud Islamic University (IMSIU), Riyadh 11623, Saudi Arabia; (M.A.M.A.); (F.B.)
| | - Fehmi Boufahja
- Department of Biology, College of Science, Imam Mohammad Ibn Saud Islamic University (IMSIU), Riyadh 11623, Saudi Arabia; (M.A.M.A.); (F.B.)
| | - Mashael A. Alghamdi
- Department of Chemistry, Imam Mohammad Ibn Saud Islamic University (IMSIU), Riyadh 11623, Saudi Arabia;
| | - Wael A. H. Hegazy
- Department of Microbiology and Immunology, Faculty of Pharmacy, Zagazig University, Zagazig 44519, Egypt; (S.I.N.); (H.A.A.); (N.M.S.)
- Pharmacy Program, Department of Pharmaceutical Sciences, Oman College of Health Sciences, Muscat 113, Oman
| | - Noura M. Seleem
- Department of Microbiology and Immunology, Faculty of Pharmacy, Zagazig University, Zagazig 44519, Egypt; (S.I.N.); (H.A.A.); (N.M.S.)
| |
Collapse
|
2
|
Khayat MT, Elbaramawi SS, Nazeih SI, Safo MK, Khafagy ES, Ali MAM, Abbas HA, Hegazy WAH, Seleem NM. Diminishing the Pathogenesis of the Food-Borne Pathogen Serratia marcescens by Low Doses of Sodium Citrate. BIOLOGY 2023; 12:biology12040504. [PMID: 37106705 PMCID: PMC10135860 DOI: 10.3390/biology12040504] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/05/2023] [Revised: 03/21/2023] [Accepted: 03/25/2023] [Indexed: 03/29/2023]
Abstract
Protecting food from bacterial contamination is crucial for ensuring its safety and avoiding foodborne illness. Serratia marcescens is one of the food bacterial contaminants that can form biofilms and pigments that spoil the food product and could cause infections and illness to the consumer. Food preservation is essential to diminish such bacterial contaminants or at least reduce their pathogenesis; however, it should not affect food odor, taste, and consistency and must be safe. Sodium citrate is a well-known safe food additive and the current study aims to evaluate its anti-virulence and anti-biofilm activity at low concentrations against S. marcescens. The anti-virulence and antibiofilm activities of sodium citrate were evaluated phenotypically and genotypically. The results showed the significant effect of sodium citrate on decreasing the biofilm formation and other virulence factors, such as motility and the production of prodigiosin, protease, and hemolysins. This could be owed to its downregulating effect on the virulence-encoding genes. An in vivo investigation was conducted on mice and the histopathological examination of isolated tissues from the liver and kidney of mice confirmed the anti-virulence activity of sodium citrate. In addition, an in silico docking study was conducted to evaluate the sodium citrate binding ability to S. marcescens quorum sensing (QS) receptors that regulates its virulence. Sodium citrate showed a marked virtual ability to compete on QS proteins, which could explain sodium citrate’s anti-virulence effect. In conclusion, sodium citrate is a safe food additive and can be used at low concentrations to prevent contamination and biofilm formation by S. marcescens and other bacteria.
Collapse
Affiliation(s)
- Maan T. Khayat
- Department of Pharmaceutical Chemistry, Faculty of Pharmacy, King Abdulaziz University, Jeddah 21589, Saudi Arabia
- Correspondence: (M.T.K.); (W.A.H.H.)
| | - Samar S. Elbaramawi
- Medicinal Chemistry Department, Faculty of Pharmacy, Zagazig University, Zagazig 44519, Egypt
| | - Shaimaa I. Nazeih
- Department of Microbiology and Immunology, Faculty of Pharmacy, Zagazig University, Zagazig 44519, Egypt
| | - Martin K. Safo
- Department of Medicinal Chemistry, School of Pharmacy, Virginia Commonwealth University, Richmond, VA 23219, USA
| | - El-Sayed Khafagy
- Department of Pharmaceutics, College of Pharmacy, Prince Sattam Bin Abdulaziz University, Al-kharj 11942, Saudi Arabia
- Department of Pharmaceutics and Industrial Pharmacy, Faculty of Pharmacy, Suez Canal University, Ismailia 41552, Egypt
| | - Mohamed A. M. Ali
- Department of Biology, College of Science, Imam Mohammad Ibn Saud Islamic University, Riyadh 11432, Saudi Arabia
- Department of Biochemistry, Faculty of Science, Ain Shams University, Cairo 11566, Egypt
| | - Hisham A. Abbas
- Department of Microbiology and Immunology, Faculty of Pharmacy, Zagazig University, Zagazig 44519, Egypt
| | - Wael A. H. Hegazy
- Department of Microbiology and Immunology, Faculty of Pharmacy, Zagazig University, Zagazig 44519, Egypt
- Pharmacy Program, Department of Pharmaceutical Sciences, Oman College of Health Sciences, Muscat 113, Oman
- Correspondence: (M.T.K.); (W.A.H.H.)
| | - Noura M. Seleem
- Department of Microbiology and Immunology, Faculty of Pharmacy, Zagazig University, Zagazig 44519, Egypt
| |
Collapse
|
3
|
Przepiora T, Figaj D, Bogucka A, Fikowicz-Krosko J, Czajkowski R, Hugouvieux-Cotte-Pattat N, Skorko-Glonek J. The Periplasmic Oxidoreductase DsbA Is Required for Virulence of the Phytopathogen Dickeya solani. Int J Mol Sci 2022; 23:ijms23020697. [PMID: 35054882 PMCID: PMC8775594 DOI: 10.3390/ijms23020697] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2021] [Revised: 01/04/2022] [Accepted: 01/06/2022] [Indexed: 02/01/2023] Open
Abstract
In bacteria, the DsbA oxidoreductase is a crucial factor responsible for the introduction of disulfide bonds to extracytoplasmic proteins, which include important virulence factors. A lack of proper disulfide bonds frequently leads to instability and/or loss of protein function; therefore, improper disulfide bonding may lead to avirulent phenotypes. The importance of the DsbA function in phytopathogens has not been extensively studied yet. Dickeya solani is a bacterium from the Soft Rot Pectobacteriaceae family which is responsible for very high economic losses mainly in potato. In this work, we constructed a D. solani dsbA mutant and demonstrated that a lack of DsbA caused a loss of virulence. The mutant bacteria showed lower activities of secreted virulence determinants and were unable to develop disease symptoms in a potato plant. The SWATH-MS-based proteomic analysis revealed that the dsbA mutation led to multifaceted effects in the D. solani cells, including not only lower levels of secreted virulence factors, but also the induction of stress responses. Finally, the outer membrane barrier seemed to be disturbed by the mutation. Our results clearly demonstrate that the function played by the DsbA oxidoreductase is crucial for D. solani virulence, and a lack of DsbA significantly disturbs cellular physiology.
Collapse
Affiliation(s)
- Tomasz Przepiora
- Department of General and Medical Biochemistry, Faculty of Biology, University of Gdansk, Wita Stwosza 59, 80-308 Gdansk, Poland; (T.P.); (D.F.)
| | - Donata Figaj
- Department of General and Medical Biochemistry, Faculty of Biology, University of Gdansk, Wita Stwosza 59, 80-308 Gdansk, Poland; (T.P.); (D.F.)
| | - Aleksandra Bogucka
- Laboratory of Mass Spectrometry, Intercollegiate Faculty of Biotechnology, University of Gdansk and Medical University of Gdansk, Abrahama 58, 80-807 Gdansk, Poland;
| | - Jakub Fikowicz-Krosko
- Laboratory of Biologically Active Compounds, Intercollegiate Faculty of Biotechnology, University of Gdansk and Medical University of Gdansk, Abrahama 58, 80-807 Gdansk, Poland; (J.F.-K.); (R.C.)
| | - Robert Czajkowski
- Laboratory of Biologically Active Compounds, Intercollegiate Faculty of Biotechnology, University of Gdansk and Medical University of Gdansk, Abrahama 58, 80-807 Gdansk, Poland; (J.F.-K.); (R.C.)
| | - Nicole Hugouvieux-Cotte-Pattat
- Microbiologie Adaptation et Pathogénie, Université Lyon, CNRS, INSA Lyon, Université Claude Bernard Lyon 1, Campus LyonTech-la Doua Bâtiment André Lwoff 10 rue Raphaël Dubois 69622, F69622 Villeurbanne, France;
| | - Joanna Skorko-Glonek
- Department of General and Medical Biochemistry, Faculty of Biology, University of Gdansk, Wita Stwosza 59, 80-308 Gdansk, Poland; (T.P.); (D.F.)
- Correspondence:
| |
Collapse
|
4
|
Quintero-Yanes A, Lee CM, Monson R, Salmond G. The FloR master regulator controls flotation, virulence and antibiotic production in Serratia sp. ATCC 39006. Environ Microbiol 2020; 22:2921-2938. [PMID: 32352190 DOI: 10.1111/1462-2920.15048] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2020] [Revised: 04/23/2020] [Accepted: 04/25/2020] [Indexed: 11/26/2022]
Abstract
Serratia sp. ATCC 39006 produces intracellular gas vesicles to enable upward flotation in water columns. It also uses flagellar rotation to swim through liquid and swarm across semi-solid surfaces. Flotation and motility can be co-regulated with production of a β-lactam antibiotic (carbapenem carboxylate) and a linear tripyrrole red antibiotic, prodigiosin. Production of gas vesicles, carbapenem and prodigiosin antibiotics, and motility are controlled by master transcriptional and post-transcriptional regulators, including the SmaI/SmaR-based quorum sensing system and the mRNA binding protein, RsmA. Recently, the ribose operon repressor, RbsR, was also defined as a pleiotropic regulator of flotation and virulence factor elaboration in this strain. Here, we report the discovery of a new global regulator (FloR; a DeoR family transcription factor) that modulates flotation through control of gas vesicle morphogenesis. The floR mutation is highly pleiotropic, down-regulating production of gas vesicles, carbapenem and prodigiosin antibiotics, and infection in Caenorhabditis elegans, but up-regulating flagellar motility. Detailed proteomic analysis using TMT peptide labelling and LC-MS/MS revealed that FloR is a physiological master regulator that operates through subordinate pleiotropic regulators including Rap, RpoS, RsmA, PigU, PstS and PigT.
Collapse
Affiliation(s)
- Alex Quintero-Yanes
- Department of Biochemistry, University of Cambridge, Hopkins Building, Downing Site, Cambridge, CB2 1QW, UK.,Bacterial Cell cycle and Development (BCcD), University of Namur, 61 Rue de Bruxelles, Namur, 5000, Belgium
| | - Chin Mei Lee
- Department of Biochemistry, University of Cambridge, Hopkins Building, Downing Site, Cambridge, CB2 1QW, UK.,Faculty of Industrial Sciences and Technology, Universiti Malaysia Pahang, Gambang, 26300, Malaysia
| | - Rita Monson
- Department of Biochemistry, University of Cambridge, Hopkins Building, Downing Site, Cambridge, CB2 1QW, UK
| | - George Salmond
- Department of Biochemistry, University of Cambridge, Hopkins Building, Downing Site, Cambridge, CB2 1QW, UK
| |
Collapse
|
5
|
Finney AJ, Lowden R, Fleszar M, Albareda M, Coulthurst SJ, Sargent F. The plant pathogen Pectobacterium atrosepticum contains a functional formate hydrogenlyase-2 complex. Mol Microbiol 2019; 112:1440-1452. [PMID: 31420965 PMCID: PMC7384014 DOI: 10.1111/mmi.14370] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/13/2019] [Indexed: 12/19/2022]
Abstract
Pectobacterium atrosepticum SCRI1043 is a phytopathogenic Gram-negative enterobacterium. Genomic analysis has identified that genes required for both respiration and fermentation are expressed under anaerobic conditions. One set of anaerobically expressed genes is predicted to encode an important but poorly understood membrane-bound enzyme termed formate hydrogenlyase-2 (FHL-2), which has fascinating evolutionary links to the mitochondrial NADH dehydrogenase (Complex I). In this work, molecular genetic and biochemical approaches were taken to establish that FHL-2 is fully functional in P. atrosepticum and is the major source of molecular hydrogen gas generated by this bacterium. The FHL-2 complex was shown to comprise a rare example of an active [NiFe]-hydrogenase-4 (Hyd-4) isoenzyme, itself linked to an unusual selenium-free formate dehydrogenase in the final complex. In addition, further genetic dissection of the genes encoding the predicted membrane arm of FHL-2 established surprisingly that the majority of genes encoding this domain are not required for physiological hydrogen production activity. Overall, this study presents P. atrosepticum as a new model bacterial system for understanding anaerobic formate and hydrogen metabolism in general, and FHL-2 function and structure in particular.
Collapse
Affiliation(s)
- Alexander J Finney
- School of Natural & Environmental Sciences, Newcastle University, Newcastle Upon Tyne, NE1 7RU, UK.,School of Life Sciences, University of Dundee, Dundee, DD1 5EH, UK
| | - Rebecca Lowden
- School of Life Sciences, University of Dundee, Dundee, DD1 5EH, UK
| | - Michal Fleszar
- School of Life Sciences, University of Dundee, Dundee, DD1 5EH, UK
| | - Marta Albareda
- School of Life Sciences, University of Dundee, Dundee, DD1 5EH, UK.,Centro de Biotecnología y Genómica de Plantas (C.B.G.P.) UPM-INIA, Universidad Politécnica de Madrid, Campus de Montegancedo, Pozuelo de Alarcón, 28223, Spain
| | | | - Frank Sargent
- School of Natural & Environmental Sciences, Newcastle University, Newcastle Upon Tyne, NE1 7RU, UK.,School of Life Sciences, University of Dundee, Dundee, DD1 5EH, UK
| |
Collapse
|
6
|
Li L, Yuan L, Shi Y, Xie X, Chai A, Wang Q, Li B. Comparative genomic analysis of Pectobacterium carotovorum subsp. brasiliense SX309 provides novel insights into its genetic and phenotypic features. BMC Genomics 2019; 20:486. [PMID: 31195968 PMCID: PMC6567464 DOI: 10.1186/s12864-019-5831-x] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2018] [Accepted: 05/23/2019] [Indexed: 12/20/2022] Open
Abstract
Background Pectobacterium carotovorum subsp. brasiliense is a broad host range bacterial pathogen, which causes blackleg of potatoes and bacterial soft rot of vegetables worldwide. Production of plant cell wall degrading enzymes is usually critical for Pectobacterium infection. However, other virulence factors and the mechanisms of genetic adaptation still need to be studied in detail. Results In this study, the complete genome of P. carotovorum subsp. brasiliense strain SX309 isolated from cucumber was compared with eight other pathogenic bacteria belonging to the Pectobacterium genus, which were isolated from various host plants. Genome comparison revealed that most virulence genes are highly conserved in the Pectobacterium strains, especially for the key virulence determinants involved in the biosynthesis of extracellular enzymes and others including the type II and III secretion systems, quorum sensing system, flagellar and chemotactic genes. Nevertheless, some variable regions of the T6SS and the CRISP-Cas immune system are unique for P. carotovorum subsp. brasiliense. Conclusions The extensive comparative genomics analysis revealed highly conserved virulence genes in the Pectobacterium strains. However, several variable regions of type VI secretion system and two subtype Cas mechanism-Cas immune systems possibly contribute to the process of Pectobacterium infection and adaptive immunity. Electronic supplementary material The online version of this article (10.1186/s12864-019-5831-x) contains supplementary material, which is available to authorized users.
Collapse
Affiliation(s)
- Lei Li
- Institute of Vegetables and Flowers, Chinese Academy of Agricultural Sciences, Beijing, 100081, China
| | - Lifang Yuan
- Institute of Vegetables and Flowers, Chinese Academy of Agricultural Sciences, Beijing, 100081, China.,Department of Plant Pathology, College of Plant Protection, China Agricultural University, Beijing, 100193, China
| | - Yanxia Shi
- Institute of Vegetables and Flowers, Chinese Academy of Agricultural Sciences, Beijing, 100081, China
| | - Xuewen Xie
- Institute of Vegetables and Flowers, Chinese Academy of Agricultural Sciences, Beijing, 100081, China
| | - Ali Chai
- Institute of Vegetables and Flowers, Chinese Academy of Agricultural Sciences, Beijing, 100081, China
| | - Qi Wang
- Department of Plant Pathology, College of Plant Protection, China Agricultural University, Beijing, 100193, China
| | - Baoju Li
- Institute of Vegetables and Flowers, Chinese Academy of Agricultural Sciences, Beijing, 100081, China.
| |
Collapse
|
7
|
Quintero-Yanes A, Monson RE, Salmond GPC. Environmental potassium regulates bacterial flotation, antibiotic production and turgor pressure in Serratia through the TrkH transporter. Environ Microbiol 2019; 21:2499-2510. [PMID: 31012245 PMCID: PMC6617781 DOI: 10.1111/1462-2920.14637] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2019] [Revised: 04/16/2019] [Accepted: 04/21/2019] [Indexed: 11/28/2022]
Abstract
Serratia sp. strain ATCC 39006 (S39006) can float in aqueous environments due to natural production of gas vesicles (GVs). Expression of genes for GV morphogenesis is stimulated in low oxygen conditions, thereby enabling migration to the air–liquid interface. Quorum sensing (via SmaI and SmaR) and transcriptional and post‐transcriptional regulators, including RbsR and RsmA, respectively, connect the control of cell buoyancy, motility and secondary metabolism. Here, we define a new pleiotropic regulator found in screens of GV mutants. A mutation in the gene trkH, encoding a potassium transporter, caused upregulation of GV formation, flotation, and the prodigiosin antibiotic, and downregulation of flagellar motility. Pressure nephelometry revealed that the mutation in trkH affected cell turgor pressure. Our results show that osmotic change is an important physiological parameter modulating cell buoyancy and antimicrobial production in S39006, in response to environmental potassium levels.
Collapse
Affiliation(s)
- Alex Quintero-Yanes
- Department of Biochemistry, University of Cambridge, Hopkins Building, Downing Site. Cambridge, CB2 1QW, UK
| | - Rita E Monson
- Department of Biochemistry, University of Cambridge, Hopkins Building, Downing Site. Cambridge, CB2 1QW, UK
| | - George P C Salmond
- Department of Biochemistry, University of Cambridge, Hopkins Building, Downing Site. Cambridge, CB2 1QW, UK
| |
Collapse
|
8
|
Torres M, Dessaux Y, Llamas I. Saline Environments as a Source of Potential Quorum Sensing Disruptors to Control Bacterial Infections: A Review. Mar Drugs 2019; 17:md17030191. [PMID: 30934619 PMCID: PMC6471967 DOI: 10.3390/md17030191] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2019] [Revised: 03/19/2019] [Accepted: 03/20/2019] [Indexed: 12/12/2022] Open
Abstract
Saline environments, such as marine and hypersaline habitats, are widely distributed around the world. They include sea waters, saline lakes, solar salterns, or hypersaline soils. The bacteria that live in these habitats produce and develop unique bioactive molecules and physiological pathways to cope with the stress conditions generated by these environments. They have been described to produce compounds with properties that differ from those found in non-saline habitats. In the last decades, the ability to disrupt quorum-sensing (QS) intercellular communication systems has been identified in many marine organisms, including bacteria. The two main mechanisms of QS interference, i.e., quorum sensing inhibition (QSI) and quorum quenching (QQ), appear to be a more frequent phenomenon in marine aquatic environments than in soils. However, data concerning bacteria from hypersaline habitats is scarce. Salt-tolerant QSI compounds and QQ enzymes may be of interest to interfere with QS-regulated bacterial functions, including virulence, in sectors such as aquaculture or agriculture where salinity is a serious environmental issue. This review provides a global overview of the main works related to QS interruption in saline environments as well as the derived biotechnological applications.
Collapse
Affiliation(s)
- Marta Torres
- Department of Microbiology, Faculty of Pharmacy, University of Granada, 18071 Granada, Spain.
- Institute of Biotechnology, Biomedical Research Center (CIBM), University of Granada, 18100 Granada, Spain.
- Institute for Integrative Biology of the Cell (I2BC), CEA/CNRS/University Paris-Sud, University Paris-Saclay, 91198 Gif-sur-Yvette, France.
| | - Yves Dessaux
- Institute for Integrative Biology of the Cell (I2BC), CEA/CNRS/University Paris-Sud, University Paris-Saclay, 91198 Gif-sur-Yvette, France.
| | - Inmaculada Llamas
- Department of Microbiology, Faculty of Pharmacy, University of Granada, 18071 Granada, Spain.
- Institute of Biotechnology, Biomedical Research Center (CIBM), University of Granada, 18100 Granada, Spain.
| |
Collapse
|
9
|
Heinrich AK, Hirschmann M, Neubacher N, Bode HB. LuxS-dependent AI-2 production is not involved in global regulation of natural product biosynthesis in Photorhabdus and Xenorhabdus. PeerJ 2017; 5:e3471. [PMID: 28663937 PMCID: PMC5488855 DOI: 10.7717/peerj.3471] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2017] [Accepted: 05/26/2017] [Indexed: 01/06/2023] Open
Abstract
The Gram-negative bacteria Photorhabdus and Xenorhabdus are known to produce a variety of different natural products (NP). These compounds play different roles since the bacteria live in symbiosis with nematodes and are pathogenic to insect larvae in the soil. Thus, a fine tuned regulatory system controlling NP biosynthesis is indispensable. Global regulators such as Hfq, Lrp, LeuO and HexA have been shown to influence NP production of Photorhabdus and Xenorhabdus. Additionally, photopyrones as quorum sensing (QS) signals were demonstrated to be involved in the regulation of NP production in Photorhabdus. In this study, we investigated the role of another possible QS signal, autoinducer-2 (AI-2), in regulation of NP production. The AI-2 synthase (LuxS) is widely distributed within the bacterial kingdom and has a dual role as a part of the activated methyl cycle pathway, as well as being responsible for AI-2 precursor production. We deleted luxS in three different entomopathogenic bacteria and compared NP levels in the mutant strains to the wild type (WT) but observed no difference to the WT strains. Furthermore, the absence of the small regulatory RNA micA, which is encoded directly upstream of luxS, did not influence NP levels. Phenotypic differences between the P. luminescens luxS deletion mutant and an earlier described luxS deficient strain of P. luminescens suggested that two phenotypically different strains have evolved in different laboratories.
Collapse
Affiliation(s)
- Antje K. Heinrich
- Fachbereich Biowissenschaften, Merck Stiftungsprofessur für Molekulare Biotechnologie, Goethe-Universität Frankfurt, Frankfurt am Main, Germany
| | - Merle Hirschmann
- Fachbereich Biowissenschaften, Merck Stiftungsprofessur für Molekulare Biotechnologie, Goethe-Universität Frankfurt, Frankfurt am Main, Germany
| | - Nick Neubacher
- Fachbereich Biowissenschaften, Merck Stiftungsprofessur für Molekulare Biotechnologie, Goethe-Universität Frankfurt, Frankfurt am Main, Germany
| | - Helge B. Bode
- Fachbereich Biowissenschaften, Merck Stiftungsprofessur für Molekulare Biotechnologie, Goethe-Universität Frankfurt, Frankfurt am Main, Germany
- Buchmann Institute for Molecular Life Sciences, Goethe-Universität Frankfurt, Frankfurt am Main, Germany
| |
Collapse
|
10
|
Wang C, Deng ZL, Xie ZM, Chu XY, Chang JW, Kong DX, Li BJ, Zhang HY, Chen LL. Construction of a genome-scale metabolic network of the plant pathogen Pectobacterium carotovorum provides new strategies for bactericide discovery. FEBS Lett 2014; 589:285-94. [PMID: 25535697 DOI: 10.1016/j.febslet.2014.12.010] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2014] [Revised: 12/10/2014] [Accepted: 12/12/2014] [Indexed: 11/17/2022]
Abstract
We reconstructed the first genome-scale metabolic network of the plant pathogen Pectobacterium carotovorum subsp. carotovorum PC1 based on its genomic sequence, annotation, and physiological data. Metabolic characteristics were analyzed using flux balance analysis (FBA), and the results were afterwards validated by phenotype microarray (PM) experiments. The reconstructed genome-scale metabolic model, iPC1209, contains 2235 reactions, 1113 metabolites and 1209 genes. We identified 19 potential bactericide targets through a comprehensive in silico gene-deletion study. Next, we performed virtual screening to identify candidate inhibitors for an important potential drug target, alkaline phosphatase, and experimentally verified that three lead compounds were able to inhibit both bacterial cell viability and the activity of alkaline phosphatase in vitro. This study illustrates a new strategy for the discovery of agricultural bactericides.
Collapse
Affiliation(s)
- Cheng Wang
- State Key Laboratory of Agricultural Microbiology, College of Informatics, Huazhong Agricultural University, Wuhan 430070, PR China; Agricultural Bioinformatics Key Laboratory of Hubei Province, Center for Bioinformatics, Huazhong Agricultural University, Wuhan 430070, PR China
| | - Zhi-Luo Deng
- Agricultural Bioinformatics Key Laboratory of Hubei Province, Center for Bioinformatics, Huazhong Agricultural University, Wuhan 430070, PR China
| | - Zhi-Ming Xie
- Agricultural Bioinformatics Key Laboratory of Hubei Province, Center for Bioinformatics, Huazhong Agricultural University, Wuhan 430070, PR China
| | - Xin-Yi Chu
- Agricultural Bioinformatics Key Laboratory of Hubei Province, Center for Bioinformatics, Huazhong Agricultural University, Wuhan 430070, PR China
| | - Ji-Wei Chang
- State Key Laboratory of Agricultural Microbiology, College of Informatics, Huazhong Agricultural University, Wuhan 430070, PR China; Agricultural Bioinformatics Key Laboratory of Hubei Province, Center for Bioinformatics, Huazhong Agricultural University, Wuhan 430070, PR China
| | - De-Xin Kong
- State Key Laboratory of Agricultural Microbiology, College of Informatics, Huazhong Agricultural University, Wuhan 430070, PR China; Agricultural Bioinformatics Key Laboratory of Hubei Province, Center for Bioinformatics, Huazhong Agricultural University, Wuhan 430070, PR China
| | - Bao-Ju Li
- Institute of Vegetables and Flowers, Chinese Academy of Agricultural Sciences, Beijing 100081, PR China
| | - Hong-Yu Zhang
- Agricultural Bioinformatics Key Laboratory of Hubei Province, Center for Bioinformatics, Huazhong Agricultural University, Wuhan 430070, PR China
| | - Ling-Ling Chen
- State Key Laboratory of Agricultural Microbiology, College of Informatics, Huazhong Agricultural University, Wuhan 430070, PR China; Agricultural Bioinformatics Key Laboratory of Hubei Province, Center for Bioinformatics, Huazhong Agricultural University, Wuhan 430070, PR China.
| |
Collapse
|
11
|
Soberón JR, Sgariglia MA, Dip Maderuelo MR, Andina ML, Sampietro DA, Vattuone MA. Antibacterial activities of Ligaria cuneifolia and Jodina rhombifolia leaf extracts against phytopathogenic and clinical bacteria. J Biosci Bioeng 2014; 118:599-605. [PMID: 24894684 DOI: 10.1016/j.jbiosc.2014.04.018] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2013] [Revised: 04/22/2014] [Accepted: 04/24/2014] [Indexed: 11/24/2022]
Abstract
Six plant extracts prepared from Ligaria cuneifolia and Jodina rhombifolia were screened for their potential antimicrobial activities against phytopathogens and clinically standard reference bacterial strains. Bioautography and broth microdilution methods were used to study samples antibacterial activities against 7 bacterial strains. The minimum inhibitory concentrations (MICs) and minimum bactericidal concentrations (MBCs) of samples were attained. An antibacterial activity guided isolation and identification of active compounds was carried out for L. cuneifolia methanolic extract (LCME). Both methanolic and aqueous extracts from L. cuneifolia showed inhibitory activities against phytopathogenic bacteria, with MICs ranging from 2.5 to 156 μg mL(-1) for LCME and 5 mg mL(-1) for the aqueous extract. None of the three J. rhombifolia extracts showed significant antibacterial activities against phytopathogenic strains (MIC > 5 mg mL(-1)), except for the aqueous extracts against Pseudomonas syringae (MIC = 312 μg mL(-1)). Only LCME showed bactericidal activities against phytopathogenic strains (MBCs = 78 μg mL(-1)). The LCME exhibited significant inhibitory activity against reference clinical strains: Escherichia coli (MIC = 156 μg mL(-1)) and Staphylococcus aureus (MIC = 78 μg mL(-1), MBC = 312 μg mL(-1)). LCME active compounds were identified as flavonol mono and diglycosides, and gallic acid. The antibacterial activity of purified compounds was also evaluated. A synergistic effect against S. aureus was found between gallic acid and a quercetin glycoside. Hence, anti-phytopathogenic bacteria potential compounds isolated from L. cuneifolia could be used as an effective source against bacterial diseases in plants.
Collapse
Affiliation(s)
- José R Soberón
- Laboratorio de Biología de Agentes Bioactivos y Fitopatógenos (LABIFITO), Facultad de Bioquímica, Química y Farmacia, Universidad Nacional de Tucumán, Ayacucho 471, T4000INI San Miguel de Tucumán, Tucumán, Argentina; Universidad Nacional de Tucumán, Ayacucho 491, T4000INI San Miguel de Tucumán, Tucumán, Argentina; Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Av. Rivadavia 1917, C1033AAJ Ciudad Autónoma de Buenos Aires, Argentina.
| | - Melina A Sgariglia
- Laboratorio de Biología de Agentes Bioactivos y Fitopatógenos (LABIFITO), Facultad de Bioquímica, Química y Farmacia, Universidad Nacional de Tucumán, Ayacucho 471, T4000INI San Miguel de Tucumán, Tucumán, Argentina; Universidad Nacional de Tucumán, Ayacucho 491, T4000INI San Miguel de Tucumán, Tucumán, Argentina; Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Av. Rivadavia 1917, C1033AAJ Ciudad Autónoma de Buenos Aires, Argentina
| | - María R Dip Maderuelo
- Universidad Nacional de Tucumán, Ayacucho 491, T4000INI San Miguel de Tucumán, Tucumán, Argentina
| | - María L Andina
- Laboratorio de Biología de Agentes Bioactivos y Fitopatógenos (LABIFITO), Facultad de Bioquímica, Química y Farmacia, Universidad Nacional de Tucumán, Ayacucho 471, T4000INI San Miguel de Tucumán, Tucumán, Argentina; Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Av. Rivadavia 1917, C1033AAJ Ciudad Autónoma de Buenos Aires, Argentina
| | - Diego A Sampietro
- Laboratorio de Biología de Agentes Bioactivos y Fitopatógenos (LABIFITO), Facultad de Bioquímica, Química y Farmacia, Universidad Nacional de Tucumán, Ayacucho 471, T4000INI San Miguel de Tucumán, Tucumán, Argentina; Universidad Nacional de Tucumán, Ayacucho 491, T4000INI San Miguel de Tucumán, Tucumán, Argentina; Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Av. Rivadavia 1917, C1033AAJ Ciudad Autónoma de Buenos Aires, Argentina
| | - Marta A Vattuone
- Laboratorio de Biología de Agentes Bioactivos y Fitopatógenos (LABIFITO), Facultad de Bioquímica, Química y Farmacia, Universidad Nacional de Tucumán, Ayacucho 471, T4000INI San Miguel de Tucumán, Tucumán, Argentina; Universidad Nacional de Tucumán, Ayacucho 491, T4000INI San Miguel de Tucumán, Tucumán, Argentina; Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Av. Rivadavia 1917, C1033AAJ Ciudad Autónoma de Buenos Aires, Argentina
| |
Collapse
|
12
|
Zaitseva YV, Popova AA, Khmel IA. Quorum sensing regulation in bacteria of the family enterobacteriaceae. RUSS J GENET+ 2014. [DOI: 10.1134/s1022795414030120] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
|
13
|
Tan H, West JA, Ramsay JP, Monson RE, Griffin JL, Toth IK, Salmond GPC. Comprehensive overexpression analysis of cyclic-di-GMP signalling proteins in the phytopathogen Pectobacterium atrosepticum reveals diverse effects on motility and virulence phenotypes. MICROBIOLOGY-SGM 2014; 160:1427-1439. [PMID: 24760967 DOI: 10.1099/mic.0.076828-0] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Bis-(3'-5')-cyclic dimeric guanosine monophosphate (c-di-GMP) is a ubiquitous bacterial signalling molecule produced by diguanylate cyclases of the GGDEF-domain family. Elevated c-di-GMP levels or increased GGDEF protein expression is frequently associated with the onset of sessility and biofilm formation in numerous bacterial species. Conversely, phosphodiesterase-dependent diminution of c-di-GMP levels by EAL- and HD-GYP-domain proteins is often accompanied by increased motility and virulence. In this study, we individually overexpressed 23 predicted GGDEF, EAL or HD-GYP-domain proteins encoded by the phytopathogen Pectobacterium atrosepticum strain SCRI1043. MS-based detection of c-di-GMP and 5'-phosphoguanylyl-(3'-5')-guanosine in these strains revealed that overexpression of most genes promoted modest 1-10-fold changes in cellular levels of c-di-GMP, with the exception of the GGDEF-domain proteins ECA0659 and ECA3374, which induced 1290- and 7660-fold increases, respectively. Overexpression of most EAL domain proteins increased motility, while overexpression of most GGDEF domain proteins reduced motility and increased poly-β-1,6-N-acetyl-glucosamine-dependent flocculation. In contrast to domain-based predictions, overexpression of the EAL protein ECA3549 or the HD-GYP protein ECA3548 increased c-di-GMP concentrations and reduced motility. Most overexpression constructs altered the levels of secreted cellulases, pectinases and proteases, confirming c-di-GMP regulation of virulence in Pe. atrosepticum. However, there was no apparent correlation between virulence-factor induction and the domain class expressed or cellular c-di-GMP levels, suggesting that regulation was in response to specific effectors within the network, rather than total c-di-GMP concentration. Finally, we demonstrated that the cellular localization patterns vary considerably for GGDEF/EAL/HD-GYP proteins, indicating it is a likely factor restricting specific interactions within the c-di-GMP network.
Collapse
Affiliation(s)
- H Tan
- Department of Biochemistry, University of Cambridge, Cambridge CB2 1QW, UK
| | - J A West
- Department of Biochemistry, University of Cambridge, Cambridge CB2 1QW, UK
| | - J P Ramsay
- Department of Biochemistry, University of Cambridge, Cambridge CB2 1QW, UK
| | - R E Monson
- Department of Biochemistry, University of Cambridge, Cambridge CB2 1QW, UK
| | - J L Griffin
- Department of Biochemistry, University of Cambridge, Cambridge CB2 1QW, UK
| | - I K Toth
- Cell and Molecular Sciences, James Hutton Institute, Invergowrie, Dundee DD2 5DA, UK
| | - G P C Salmond
- Department of Biochemistry, University of Cambridge, Cambridge CB2 1QW, UK
| |
Collapse
|
14
|
Lee DH, Kim JB, Kim M, Roh E, Jung K, Choi M, Oh C, Choi J, Yun J, Heu S. Microbiota on spoiled vegetables and their characterization. J Food Prot 2013; 76:1350-8. [PMID: 23905790 DOI: 10.4315/0362-028x.jfp-12-439] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Spoilage causes vegetables to deteriorate and develop unpleasant characteristics. Approximately 30 % of fresh vegetables are lost to spoilage, mainly due to colonization by bacteria. In the present study, a total of 44 bacterial isolates were obtained from a number of spoiled vegetables. The isolates were identified and classified into 20 different species of 14 genera based on fatty acid composition, biochemical tests, and 16S rDNA sequence analyses. Pseudomonas spp. were the species most frequently isolated from the spoiled vegetables. To evaluate the spoilage ability of each species, a variety of fresh vegetables were treated with each isolate and their degree of maceration was observed. In addition, the production of plant cell wall-degrading enzymes (PCWDEs), such as cellulase, xylanase, pectate lyase, and polygalacturonase, was compared among isolates to investigate their potential associations with spoilage. Strains that produce more PCWDEs cause spoilage on more diverse plants, and pectinase may be the most important enzyme among PCWDEs for vegetable spoilage. Most gram-negative spoilage bacteria produced acylated homoserine lactone, a quorum-sensing signal molecule, suggesting that it may be possible to use this compound effectively to prevent or slow down the spoilage of vegetables contaminated with diverse bacteria.
Collapse
Affiliation(s)
- Dong Hwan Lee
- Division of Microbial Safety, National Academy of Agricultural Science, Rural Development Administration, Suwon 441-707, Republic of Korea
| | | | | | | | | | | | | | | | | | | |
Collapse
|
15
|
Haigh R, Kumar B, Sandrini S, Freestone P. Mutation design and strain background influence the phenotype ofEscherichia coli luxSmutants. Mol Microbiol 2013; 88:951-69. [DOI: 10.1111/mmi.12237] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 04/12/2013] [Indexed: 11/28/2022]
Affiliation(s)
- Richard Haigh
- Department of Genetics; University of Leicester; Leicester UK
| | - Brijesh Kumar
- Department of Infection, Immunity and Inflammation; University of Leicester; Leicester UK
| | - Sara Sandrini
- Department of Infection, Immunity and Inflammation; University of Leicester; Leicester UK
| | - Primrose Freestone
- Department of Infection, Immunity and Inflammation; University of Leicester; Leicester UK
| |
Collapse
|
16
|
Ham JH. Intercellular and intracellular signalling systems that globally control the expression of virulence genes in plant pathogenic bacteria. MOLECULAR PLANT PATHOLOGY 2013; 14. [PMID: 23186372 PMCID: PMC6638695 DOI: 10.1111/mpp.12005] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/09/2023]
Abstract
Plant pathogenic bacteria utilize complex signalling systems to control the expression of virulence genes at the cellular level and within populations. Quorum sensing (QS), an important intercellular communication mechanism, is mediated by different types of small molecules, including N-acyl homoserine lactones (AHLs), fatty acids and small proteins. AHL-mediated signalling systems dependent on the LuxI and LuxR family proteins play critical roles in the virulence of a wide range of Gram-negative plant pathogenic bacteria belonging to the Alphaproteobacteria, Betaproteobacteria and Gammaproteobacteria. Xanthomonas spp. and Xylella fastidiosa, members of the Gammaproteobacteria, however, possess QS systems that are mediated by fatty acid-type diffusible signal factors (DSFs). Recent studies have demonstrated that Ax21, a 194-amino-acid protein in Xanthomonas oryzae pv. oryzae, plays dual functions in activating a rice innate immune pathway through binding to the rice XA21 pattern recognition receptor and in regulating bacterial virulence and biofilm formation as a QS signal molecule. In xanthomonads, DSF-mediated QS systems are connected with the signalling pathways mediated by cyclic diguanosine monophosphate (c-di-GMP), which functions as a second messenger for the control of virulence gene expression in these bacterial pathogens.
Collapse
Affiliation(s)
- Jong Hyun Ham
- Department of Plant Pathology and Crop Physiology, Louisiana State University Agricultural Center, Baton Rouge, LA 70803, USA.
| |
Collapse
|
17
|
Cox CE, McClelland M, Teplitski M. Consequences of disrupting Salmonella AI-2 signaling on interactions within soft rots. PHYTOPATHOLOGY 2013; 103:352-361. [PMID: 23324045 DOI: 10.1094/phyto-09-12-0237-fi] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
Within soft rots, Salmonella spp. reach population densities 10- to 100-fold higher than within intact plants. The hypothesis that Salmonella spp. exchange AI-2 signals with Pectobacterium carotovorum to increase its competitive fitness was tested using mutants involved in AI-2 production (luxS) or perception (lsrACDBF or lsrG). Co-infections of a wild-type Salmonella sp. and its AI-2 mutants (at ≈3 to 10(4)) were established in green or red tomato ('FL 47' or 'Campari' for 3 or 5 days) as well as tomato co-infected with Pectobacterium (at 10(9)) or its luxS mutant. There were no significant differences in the competitive fitness of Salmonella, indicating that AI-2 signaling is not a major input in the interactions between these organisms under the tested conditions. A Salmonella lsrG::tnpR-lacZ resolvase in vivo expression technology (RIVET) reporter, constructed to monitor AI-2-related gene expression, responded strongly to the luxS deletion but only weakly to external sources of AI-2. Growth in soft rots generally decreased RIVET resolution; however, the effect was not correlated to the luxS genotype of the Pectobacterium sp. The results of this study show that AI-2 signaling offers no significant benefit to Salmonella spp. in this model of colonization of tomato or soft rots.
Collapse
Affiliation(s)
- Clayton E Cox
- Department of Soil and Water Science, University of Florida, Gainesville, FL, USA.
| | | | | |
Collapse
|
18
|
Folgado R, Panis B, Sergeant K, Renaut J, Swennen R, Hausman JF. Differential Protein Expression in Response to Abiotic Stress in Two Potato Species: Solanum commersonii Dun and Solanum tuberosum L. Int J Mol Sci 2013; 14:4912-33. [PMID: 23455465 PMCID: PMC3634427 DOI: 10.3390/ijms14034912] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2012] [Revised: 02/08/2013] [Accepted: 02/13/2013] [Indexed: 01/05/2023] Open
Abstract
Better knowledge on responses to dehydration stress could help to improve the existing cryopreservation protocols for potato, since plant tissues processed for cryopreservation are often submitted to similar in vitro stress conditions. Cryopreservation (the best method of conservation for vegetatively propagated plants) of potato still needs to be standardized to make it available and to conserve the wide diversity of this crop. In the present work, the response to osmotic stress and chilling temperature was investigated in two potato species, Solanum tuberosum and its relative, frost-tolerant S. commersonii. After 14 days of exposure, different growth parameters, such as shoot length and number of leaves, were measured. Furthermore, differentially abundant proteins were identified after performing 2-fluorescence difference gel electrophoresis (2-DIGE) experiments, and soluble carbohydrates were analyzed by High Performance Anion Exchange Chromatography with Pulsed Amperometric Detection (HPAEC-PAD). The results show different responses in both species depending on the stress treatment. Focusing on the differences in growth parameters during the treatments, Solanum commersonii seems to be more affected than S. tuberosum cv. Désirée. At the molecular level, there are some differences and similarities between the two potato species studied that are dependent on the type of stressor.
Collapse
Affiliation(s)
- Raquel Folgado
- Department Environment and Agro-biotechnologies (EVA), Centre de Recherche Public—Gabriel Lippmann, 41, rue du Brill, L-4422 Belvaux, Luxembourg; E-Mails: (R.F.); (K.S.); (J.R.)
- Laboratory of Tropical Crop Improvement, Division of Crop Biotechnics, KU Leuven, Willem de Croylaan, 42 bus 2455, B-3001 Leuven, Belgium; E-Mails: (B.P.); (R.S.)
| | - Bart Panis
- Laboratory of Tropical Crop Improvement, Division of Crop Biotechnics, KU Leuven, Willem de Croylaan, 42 bus 2455, B-3001 Leuven, Belgium; E-Mails: (B.P.); (R.S.)
| | - Kjell Sergeant
- Department Environment and Agro-biotechnologies (EVA), Centre de Recherche Public—Gabriel Lippmann, 41, rue du Brill, L-4422 Belvaux, Luxembourg; E-Mails: (R.F.); (K.S.); (J.R.)
| | - Jenny Renaut
- Department Environment and Agro-biotechnologies (EVA), Centre de Recherche Public—Gabriel Lippmann, 41, rue du Brill, L-4422 Belvaux, Luxembourg; E-Mails: (R.F.); (K.S.); (J.R.)
| | - Rony Swennen
- Laboratory of Tropical Crop Improvement, Division of Crop Biotechnics, KU Leuven, Willem de Croylaan, 42 bus 2455, B-3001 Leuven, Belgium; E-Mails: (B.P.); (R.S.)
- Bioversity International, Willem de Croylaan, 42 bus 2455, B-3001 Leuven, Belgium
| | - Jean-Francois Hausman
- Department Environment and Agro-biotechnologies (EVA), Centre de Recherche Public—Gabriel Lippmann, 41, rue du Brill, L-4422 Belvaux, Luxembourg; E-Mails: (R.F.); (K.S.); (J.R.)
| |
Collapse
|
19
|
Cubitt MF, Hedley PE, Williamson NR, Morris JA, Campbell E, Toth IK, Salmond GPC. A metabolic regulator modulates virulence and quorum sensing signal production in Pectobacterium atrosepticum. MOLECULAR PLANT-MICROBE INTERACTIONS : MPMI 2013; 26:356-366. [PMID: 23113713 DOI: 10.1094/mpmi-09-12-0210-r] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
Plant cell wall-degrading enzymes (PCWDE) are key virulence determinants in the pathogenesis of the potato pathogen Pectobacterium atrosepticum. In this study, we report the impact on virulence of a transposon insertion mutation in the metJ gene that codes for the repressor of the methionine biosynthesis regulon. In a mutant strain defective for the small regulatory RNA rsmB, PCWDE are not produced and virulence in potato tubers is almost totally abolished. However, when the metJ gene is disrupted in this background, the rsmB(-) phenotype is suppressed and virulence and PCWDE production are restored. Additionally, when metJ is disrupted, production of the quorum-sensing signal, N-(3-oxohexanoyl)-homoserine lactone, is increased. The metJ mutant strains showed pleiotropic transcriptional impacts affecting approximately a quarter of the genome. Genes involved in methionine biosynthesis were most highly upregulated but many virulence-associated transcripts were also upregulated. This is the first report of the impact of the MetJ repressor on virulence in bacteria.
Collapse
Affiliation(s)
- Marion F Cubitt
- Department of Biochemistry, University of Cambridge, Cambridge, UK
| | | | | | | | | | | | | |
Collapse
|
20
|
Gerc AJ, Song L, Challis GL, Stanley-Wall NR, Coulthurst SJ. The insect pathogen Serratia marcescens Db10 uses a hybrid non-ribosomal peptide synthetase-polyketide synthase to produce the antibiotic althiomycin. PLoS One 2012; 7:e44673. [PMID: 23028578 PMCID: PMC3445576 DOI: 10.1371/journal.pone.0044673] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2012] [Accepted: 08/06/2012] [Indexed: 12/12/2022] Open
Abstract
There is a continuing need to discover new bioactive natural products, such as antibiotics, in genetically-amenable micro-organisms. We observed that the enteric insect pathogen, Serratia marcescens Db10, produced a diffusible compound that inhibited the growth of Bacillis subtilis and Staphyloccocus aureus. Mapping the genetic locus required for this activity revealed a putative natural product biosynthetic gene cluster, further defined to a six-gene operon named alb1–alb6. Bioinformatic analysis of the proteins encoded by alb1–6 predicted a hybrid non-ribosomal peptide synthetase-polyketide synthase (NRPS-PKS) assembly line (Alb4/5/6), tailoring enzymes (Alb2/3) and an export/resistance protein (Alb1), and suggested that the machinery assembled althiomycin or a related molecule. Althiomycin is a ribosome-inhibiting antibiotic whose biosynthetic machinery had been elusive for decades. Chromatographic and spectroscopic analyses confirmed that wild type S. marcescens produced althiomycin and that production was eliminated on disruption of the alb gene cluster. Construction of mutants with in-frame deletions of specific alb genes demonstrated that Alb2–Alb5 were essential for althiomycin production, whereas Alb6 was required for maximal production of the antibiotic. A phosphopantetheinyl transferase enzyme required for althiomycin biosynthesis was also identified. Expression of Alb1, a predicted major facilitator superfamily efflux pump, conferred althiomycin resistance on another, sensitive, strain of S. marcescens. This is the first report of althiomycin production outside of the Myxobacteria or Streptomyces and paves the way for future exploitation of the biosynthetic machinery, since S. marcescens represents a convenient and tractable producing organism.
Collapse
Affiliation(s)
- Amy J. Gerc
- Division of Molecular Microbiology, College of Life Sciences, University of Dundee, Dundee, United Kingdom
| | - Lijiang Song
- Department of Chemistry, University of Warwick, Coventry, United Kingdom
| | - Gregory L. Challis
- Department of Chemistry, University of Warwick, Coventry, United Kingdom
- * E-mail: (GLC); (NRS); (SJC)
| | - Nicola R. Stanley-Wall
- Division of Molecular Microbiology, College of Life Sciences, University of Dundee, Dundee, United Kingdom
- * E-mail: (GLC); (NRS); (SJC)
| | - Sarah J. Coulthurst
- Division of Molecular Microbiology, College of Life Sciences, University of Dundee, Dundee, United Kingdom
- * E-mail: (GLC); (NRS); (SJC)
| |
Collapse
|
21
|
Rezzonico F, Smits THM, Duffy B. Detection of AI-2 receptors in genomes of Enterobacteriaceae suggests a role of type-2 quorum sensing in closed ecosystems. SENSORS 2012; 12:6645-65. [PMID: 22778662 PMCID: PMC3386761 DOI: 10.3390/s120506645] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/31/2012] [Revised: 05/11/2012] [Accepted: 05/16/2012] [Indexed: 01/04/2023]
Abstract
The LuxS enzyme, an S-ribosyl-homocysteine lyase, catalyzes the production of the signal precursor for autoinducer-2 mediated quorum sensing (QS-2) in Vibrio. Its widespread occurrence among bacteria is often considered the evidence for a universal language for interspecies communication. Presence of the luxS gene and production of the autoinducer-2 (AI-2) signal have repeatedly been the only evidences presented to assign a functional QS-2 to the most diverse species. In fact, LuxS has a primary metabolic role as part of the activated methyl cycle. In this review we have analyzed the distribution of QS-2 related genes in Enterobacteriaceae by moving the focus of the investigation from AI-2 production to the detection of potential AI-2 receptors. The latter are common in pathogens or endosymbionts of animals, but were also found in a limited number of Enterobacteriaceae of the genera Enterobacter, Klebsiella, and Pantoea that live in close association with plants or fungi. Although a precise function of QS-2 in these species has not been identified, they all show an endophytic or endosymbiontic lifestyle that suggests a role of type-2 quorum sensing in the adaptation to closed ecosystems.
Collapse
Affiliation(s)
- Fabio Rezzonico
- Plant Protection Division, Agroscope Changins-Wädenswil ACW, Schloss 1, Wädenswil CH-8820, Switzerland.
| | | | | |
Collapse
|
22
|
Crépin A, Barbey C, Beury-Cirou A, Hélias V, Taupin L, Reverchon S, Nasser W, Faure D, Dufour A, Orange N, Feuilloley M, Heurlier K, Burini JF, Latour X. Quorum sensing signaling molecules produced by reference and emerging soft-rot bacteria (Dickeya and Pectobacterium spp.). PLoS One 2012; 7:e35176. [PMID: 22539957 PMCID: PMC3335102 DOI: 10.1371/journal.pone.0035176] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2012] [Accepted: 03/09/2012] [Indexed: 12/30/2022] Open
Abstract
Background Several small diffusible molecules are involved in bacterial quorum sensing and virulence. The production of autoinducers-1 and -2, quinolone, indole and γ-amino butyrate signaling molecules was investigated in a set of soft-rot bacteria belonging to six Dickeya or Pectobacterium species including recent or emerging potato isolates. Methodology/Principal Findings Using bacterial biosensors, immunoassay, and chromatographic analysis, we showed that soft-rot bacteria have the common ability to produce transiently during their exponential phase of growth the N-3-oxo-hexanoyl- or the N-3-oxo-octanoyl-l-homoserine lactones and a molecule of the autoinducer-2 family. Dickeya spp. produced in addition the indole-3-acetic acid in tryptophan-rich conditions. All these signaling molecules have been identified for the first time in the novel Dickeya solani species. In contrast, quinolone and γ-amino butyrate signals were not identified and the corresponding synthases are not present in the available genomes of soft-rot bacteria. To determine if the variations of signal production according to growth phase could result from expression modifications of the corresponding synthase gene, the respective mRNA levels were estimated by reverse transcriptase-PCR. While the N-acyl-homoserine lactone production is systematically correlated to the synthase expression, that of the autoinducer-2 follows the expression of an enzyme upstream in the activated methyl cycle and providing its precursor, rather than the expression of its own synthase. Conclusions/Significance Despite sharing the S-adenosylmethionine precursor, no strong link was detected between the production kinetics or metabolic pathways of autoinducers-1 and -2. In contrast, the signaling pathway of autoinducer-2 seems to be switched off by the indole-3-acetic acid pathway under tryptophan control. It therefore appears that the two genera of soft-rot bacteria have similarities but also differences in the mechanisms of communication via the diffusible molecules. Our results designate autoinducer-1 lactones as the main targets for a global biocontrol of soft-rot bacteria communications, including those of emerging isolates.
Collapse
Affiliation(s)
- Alexandre Crépin
- Laboratoire de Microbiologie Signaux et Microenvironnement (LMSM) - Normandie Université - Université de Rouen EA 4312 - IUT Evreux, Evreux, France
- SIPRE Comité Nord Station de Recherche et de Création Variétale, Bretteville du Grand Caux, France
| | - Corinne Barbey
- Laboratoire de Microbiologie Signaux et Microenvironnement (LMSM) - Normandie Université - Université de Rouen EA 4312 - IUT Evreux, Evreux, France
| | - Amélie Beury-Cirou
- SIPRE Comité Nord Station de Recherche et de Création Variétale, Bretteville du Grand Caux, France
- Institut des Sciences du Végétal (ISV) UPR 2355 - CNRS, Gif-sur-Yvette, France
| | - Valérie Hélias
- Fédération Nationale des Producteurs de Plants de Pomme de Terre (FN3PT), Paris, France
- Institut de Génétique Environnement et Protection des Plantes (IGEPP) UMR 1349 - INRA, Rennes, France
| | - Laure Taupin
- Laboratoire de Biotechnologie et Chimie Marines (LBCM) - Université de Bretagne-Sud EA 3884, Lorient, France
| | - Sylvie Reverchon
- Microbiologie Adaptation et Pathogénie (MAP) UMR 5240 - Université Claude Bernard Lyon 1-INSA-CNRS-Bayer CropScience, Villeurbanne, France
| | - William Nasser
- Microbiologie Adaptation et Pathogénie (MAP) UMR 5240 - Université Claude Bernard Lyon 1-INSA-CNRS-Bayer CropScience, Villeurbanne, France
| | - Denis Faure
- Institut des Sciences du Végétal (ISV) UPR 2355 - CNRS, Gif-sur-Yvette, France
| | - Alain Dufour
- Laboratoire de Biotechnologie et Chimie Marines (LBCM) - Université de Bretagne-Sud EA 3884, Lorient, France
| | - Nicole Orange
- Laboratoire de Microbiologie Signaux et Microenvironnement (LMSM) - Normandie Université - Université de Rouen EA 4312 - IUT Evreux, Evreux, France
| | - Marc Feuilloley
- Laboratoire de Microbiologie Signaux et Microenvironnement (LMSM) - Normandie Université - Université de Rouen EA 4312 - IUT Evreux, Evreux, France
| | - Karin Heurlier
- Department of Food Sciences, University of Nottingham, Sutton Bonington, United Kingdom
| | - Jean-François Burini
- Laboratoire de Microbiologie Signaux et Microenvironnement (LMSM) - Normandie Université - Université de Rouen EA 4312 - IUT Evreux, Evreux, France
| | - Xavier Latour
- Laboratoire de Microbiologie Signaux et Microenvironnement (LMSM) - Normandie Université - Université de Rouen EA 4312 - IUT Evreux, Evreux, France
- * E-mail:
| |
Collapse
|
23
|
Quorum sensing and expression of virulence in pectobacteria. SENSORS 2012; 12:3327-49. [PMID: 22737011 PMCID: PMC3376562 DOI: 10.3390/s120303327] [Citation(s) in RCA: 53] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/16/2012] [Revised: 02/21/2012] [Accepted: 03/02/2012] [Indexed: 01/23/2023]
Abstract
Quorum sensing (QS) is a population density-dependent regulatory mechanism in which gene expression is coupled to the accumulation of a chemical signaling molecule. QS systems are widespread among the plant soft-rotting bacteria. In Pectobacterium carotovorum, at least two QS systems exist being specified by the nature of chemical signals involved. QS in Pectobacterium carotovorum uses N-acylhomoserine lactone (AHL) based, as well as autoinducer-2 (AI-2) dependent signaling systems. This review will address the importance of the QS in production of virulence factors and interaction of QS with other regulatory systems in Pectobacterium carotovorum.
Collapse
|
24
|
Wilf NM, Salmond GPC. The stationary phase sigma factor, RpoS, regulates the production of a carbapenem antibiotic, a bioactive prodigiosin and virulence in the enterobacterial pathogen Serratia sp. ATCC 39006. MICROBIOLOGY-SGM 2011; 158:648-658. [PMID: 22194349 DOI: 10.1099/mic.0.055780-0] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Serratia sp. ATCC 39006 (S39006) is a Gram-negative bacterium that is virulent in plant (potato) and invertebrate animal (Caenorhabditis elegans) models. It produces two secondary metabolite antibiotics, a prodigiosin and a carbapenem, and the exoenzymes pectate lyase and cellulase. We showed previously that deletion of the RNA chaperone Hfq abolished antibiotic production and attenuated virulence in both animal and plant hosts. Hfq and dependent small RNAs (sRNAs) are known to regulate the post-transcriptional expression of rpoS, which encodes σ(S), the stationary phase sigma factor subunit of RNA polymerase. An S39006 hfq deletion mutant showed decreased transcript levels of rpoS. Therefore, in this study we investigated whether the phenotypes regulated by Hfq were mediated through its control of rpoS. Whereas loss of Hfq abolished prodigiosin and carbapenem production and attenuated virulence in both C. elegans and potato, characterization of an S39006 rpoS mutant showed unexpectedly elevated prodigiosin and carbapenem production. Furthermore, the rpoS mutant exhibited attenuated animal pathogenesis, but not plant pathogenesis. Additionally, a homologue of the Hfq-dependent sRNA, RprA, was identified and shown to regulate prodigiosin production in a manner consistent with its role in positively regulating translation of rpoS mRNA. Combined, these results demonstrate that Hfq regulation of secondary metabolism and plant pathogenesis is independent of RpoS and establishes RpoS and RprA as regulators of antibiotic production.
Collapse
Affiliation(s)
- Nabil M Wilf
- Department of Biochemistry, University of Cambridge, Tennis Court Road, Cambridge CB2 1QW, UK
| | - George P C Salmond
- Department of Biochemistry, University of Cambridge, Tennis Court Road, Cambridge CB2 1QW, UK
| |
Collapse
|
25
|
Pérez-Mendoza D, Coulthurst SJ, Sanjuán J, Salmond GPC. N-Acetylglucosamine-dependent biofilm formation in Pectobacterium atrosepticum is cryptic and activated by elevated c-di-GMP levels. MICROBIOLOGY-SGM 2011; 157:3340-3348. [PMID: 21948048 DOI: 10.1099/mic.0.050450-0] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
The phytopathogenic bacterium Pectobacterium atrosepticum (Pba) strain SCRI1043 does not exhibit appreciable biofilm formation under standard laboratory conditions. Here we show that a biofilm-forming phenotype in this strain could be activated from a cryptic state by increasing intracellular levels of c-di-GMP, through overexpression of a constitutively active diguanylate cyclase (PleD*) from Caulobacter crescentus. Randomly obtained Pba transposon mutants defective in the pga operon, involved in synthesis and translocation of poly-β-1,6-N-acetyl-D-glucosamine (PGA), were all impaired in this biofilm formation. The presence of the PGA-degrading enzyme dispersin B in the growth media prevented biofilm formation by Pba overexpressing PleD*, further supporting the importance of PGA for biofilm formation by Pba. Importantly, a pga mutant exhibited a reduction in root binding to the host plant under conditions of high intracellular c-di-GMP levels. A modest but consistent increase in pga transcript levels was associated with high intracellular levels of c-di-GMP. Our results indicate tight control of PGA-dependent biofilm formation by c-di-GMP in Pba.
Collapse
Affiliation(s)
- Daniel Pérez-Mendoza
- Departamento de Microbiología del suelo y Sistemas Simbióticos, Estación Experimental del Zaidín, CSIC, C/ Profesor Albareda 1, 18008 Granada, Spain.,Department of Biochemistry, University of Cambridge, Cambridge CB2 1QW, UK
| | - Sarah J Coulthurst
- Division of Molecular Microbiology, University of Dundee, Dundee DD1 5EH, UK
| | - Juan Sanjuán
- Departamento de Microbiología del suelo y Sistemas Simbióticos, Estación Experimental del Zaidín, CSIC, C/ Profesor Albareda 1, 18008 Granada, Spain
| | - George P C Salmond
- Department of Biochemistry, University of Cambridge, Cambridge CB2 1QW, UK
| |
Collapse
|
26
|
The opportunistic pathogen Serratia marcescens utilizes type VI secretion to target bacterial competitors. J Bacteriol 2011; 193:6057-69. [PMID: 21890705 DOI: 10.1128/jb.05671-11] [Citation(s) in RCA: 176] [Impact Index Per Article: 13.5] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The type VI secretion system (T6SS) is the most recently described and least understood of the protein secretion systems of Gram-negative bacteria. It is widely distributed and has been implicated in the virulence of various pathogens, but its mechanism and exact mode of action remain to be defined. Additionally there have been several very recent reports that some T6SSs can target bacteria rather than eukaryotic cells. Serratia marcescens is an opportunistic enteric pathogen, a class of bacteria responsible for a significant proportion of hospital-acquired infections. We describe the identification of a functional T6SS in S. marcescens strain Db10, the first report of type VI secretion by an opportunist enteric bacterium. The T6SS of S. marcescens Db10 is active, with secretion of Hcp to the culture medium readily detected, and is expressed constitutively under normal growth conditions from a large transcriptional unit. Expression of the T6SS genes did not appear to be dependent on the integrity of the T6SS. The S. marcescens Db10 T6SS is not required for virulence in three nonmammalian virulence models. It does, however, exhibit dramatic antibacterial killing activity against several other bacterial species and is required for S. marcescens to persist in a mixed culture with another opportunist pathogen, Enterobacter cloacae. Importantly, this antibacterial killing activity is highly strain specific, with the S. marcescens Db10 T6SS being highly effective against another strain of S. marcescens with a very similar and active T6SS. We conclude that type VI secretion plays a crucial role in the competitiveness, and thus indirectly the virulence, of S. marcescens and other opportunistic bacterial pathogens.
Collapse
|
27
|
Wilf NM, Williamson NR, Ramsay JP, Poulter S, Bandyra KJ, Salmond GPC. The RNA chaperone, Hfq, controls two luxR-type regulators and plays a key role in pathogenesis and production of antibiotics in Serratia sp. ATCC 39006. Environ Microbiol 2011; 13:2649-66. [PMID: 21824244 DOI: 10.1111/j.1462-2920.2011.02532.x] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
Abstract
Serratia sp. ATCC 39006 (S39006) is a Gram-negative bacterium that is virulent in plant (potato) and animal (Caenorhabditis elegans) models. It produces two secondary metabolite antibiotics, a prodigiosin and a carbapenem, and the exoenzymes, pectate lyase and cellulase. A complex regulatory network that includes quorum sensing (QS) controls production of prodigiosin. While many aspects of the regulation of the metabolites and exoenzymes are well understood, the potential role in this network of the RNA chaperone Hfq and dependent small regulatory RNAs has not been characterized. Hfq is an RNA chaperone involved in post-transcriptional regulation that plays a key role in stress response and virulence in diverse bacterial species. To explore whether Hfq-dependent processes might contribute to the regulation of antibiotic production we constructed an S39006 Δhfq mutant. Production of prodigiosin and carbapenem was abolished in this mutant strain, while production of the QS signalling molecule, butanoyl homoserine lactone (BHL), was unaffected. Using transcriptional fusions, we found that Hfq regulates the QS response regulators, SmaR and CarR. Additionally, exoenzyme production and swimming motility were decreased in a Δhfq mutant, and virulence was attenuated in potato and C. elegans models. These results suggest that an Hfq-dependent pathway is involved in the regulation of virulence and secondary metabolite production in S39006.
Collapse
Affiliation(s)
- Nabil M Wilf
- Department of Biochemistry, University of Cambridge, Tennis Court Road, Cambridge CB21QW, UK
| | | | | | | | | | | |
Collapse
|
28
|
Knief C, Delmotte N, Vorholt JA. Bacterial adaptation to life in association with plants - A proteomic perspective from culture to in situ conditions. Proteomics 2011; 11:3086-105. [PMID: 21548095 DOI: 10.1002/pmic.201000818] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2010] [Revised: 02/01/2011] [Accepted: 02/17/2011] [Indexed: 12/13/2022]
Abstract
Diverse bacterial taxa that live in association with plants affect plant health and development. This is most evident for those bacteria that undergo a symbiotic association with plants or infect the plants as pathogens. Proteome analyses have contributed significantly toward a deeper understanding of the molecular mechanisms underlying the development of these associations. They were applied to obtain a general overview of the protein composition of these bacteria, but more so to study effects of plant signaling molecules on the cytosolic proteome composition or metabolic adaptations upon plant colonization. Proteomic analyses are particularly useful for the identification of secreted proteins, which are indispensable to manipulate a host plant. Recent advances in the field of proteome analyses have initiated a new research area, the analysis of more complex microbial communities. Such studies are just at their beginning but hold great potential for the future to elucidate not only the interactions between bacteria and their host plants, but also of bacteria-bacteria interactions between different bacterial taxa when living in association with plants. These include not only the symbiotic and pathogenic bacteria, but also the commensal bacteria that are consistently found in association with plants and whose functions remain currently largely uncovered.
Collapse
Affiliation(s)
- Claudia Knief
- Institute of Microbiology, ETH Zurich, Zurich, Switzerland
| | | | | |
Collapse
|
29
|
Eberl L, Riedel K. Mining quorum sensing regulated proteins - Role of bacterial cell-to-cell communication in global gene regulation as assessed by proteomics. Proteomics 2011; 11:3070-85. [PMID: 21548094 DOI: 10.1002/pmic.201000814] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2010] [Revised: 01/20/2011] [Accepted: 02/17/2011] [Indexed: 12/31/2022]
Affiliation(s)
- Leo Eberl
- Department of Microbiology, Institute of Plant Biology, University of Zürich, Zurich, Switzerland
| | | |
Collapse
|
30
|
Di Cagno R, De Angelis M, Calasso M, Gobbetti M. Proteomics of the bacterial cross-talk by quorum sensing. J Proteomics 2011; 74:19-34. [DOI: 10.1016/j.jprot.2010.09.003] [Citation(s) in RCA: 62] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2010] [Revised: 09/14/2010] [Accepted: 09/29/2010] [Indexed: 01/03/2023]
|
31
|
Gorshkov V, Petrova O, Gogoleva N, Gogolev Y. Cell-to-cell communication in the populations of enterobacteriumErwinia carotovorassp.atrosepticaSCRI1043 during adaptation to stress conditions. ACTA ACUST UNITED AC 2010; 59:378-85. [DOI: 10.1111/j.1574-695x.2010.00684.x] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
|
32
|
Barnard AML, Simpson NJL, Lilley KS, Salmond GPC. Mutations in rpsL that confer streptomycin resistance show pleiotropic effects on virulence and the production of a carbapenem antibiotic in Erwinia carotovora. Microbiology (Reading) 2010; 156:1030-1039. [DOI: 10.1099/mic.0.034595-0] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Spontaneous streptomycin-resistant derivatives of Erwinia carotovora subsp. carotovora strain ATTn10 were isolated. Sequencing of the rpsL locus (encoding the ribosomal protein S12) showed that each mutant was missense, with a single base change, resulting in the substitution of the wild-type lysine by arginine, threonine or asparagine at codon 43. Phenotypic analyses showed that the rpsL mutants could be segregated into two groups: K43R mutants showed reduced production of the β-lactam secondary metabolite 1-carbapen-2-em-3 carboxylic acid (Car), but little effect on exoenzyme production or virulence in potato tuber tests. By contrast, the K43N and K43T mutations were pleiotropic, resulting in reduced exoenzyme production and virulence, as well as diminished Car production. The effect on Car production was due to reduced transcription of the quorum-sensing-dependent car biosynthetic genes. The effects of K43N and K43T mutations on Car production were partially alleviated by provision of an excess of the quorum-sensing signalling molecule N-(3-oxohexanoyl)-l-homoserine lactone. Finally, a proteomic analysis of the K43T mutant indicated that the abundance of a subset of intracellular proteins was affected by this rpsL mutation.
Collapse
Affiliation(s)
- Anne M. L. Barnard
- Department of Biochemistry, University of Cambridge, Tennis Court Road, Cambridge CB2 1QW, UK
| | - Natalie J. L. Simpson
- Department of Biochemistry, University of Cambridge, Tennis Court Road, Cambridge CB2 1QW, UK
| | - Kathryn S. Lilley
- Department of Biochemistry, University of Cambridge, Tennis Court Road, Cambridge CB2 1QW, UK
| | - George P. C. Salmond
- Department of Biochemistry, University of Cambridge, Tennis Court Road, Cambridge CB2 1QW, UK
| |
Collapse
|
33
|
Evans TJ, Coulthurst SJ, Komitopoulou E, Salmond GPC. Two mobile Pectobacterium atrosepticum prophages modulate virulence. FEMS Microbiol Lett 2010; 304:195-202. [PMID: 20146746 DOI: 10.1111/j.1574-6968.2010.01901.x] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023] Open
Abstract
The Pectobacterium atrosepticum strain SCRI1043 genome contains two complete prophage sequences. One, ECA41, is Mu-like and is able to integrate into, and excise from, various genomic locations. The other, ECA29, is a P2 family prophage, and is also able to excise from the genome. Excision of both prophages is rare and we were unable to induce lysis of cultures. Deletion of the entire prophages, both separately and in combination, did not affect the growth rate or the secretion of plant cell wall-degrading enzymes, but swimming motility was decreased. The virulence of prophage deletion strains in the potato host was decreased.
Collapse
Affiliation(s)
- Terry J Evans
- Department of Biochemistry, University of Cambridge, Cambridge, UK
| | | | | | | |
Collapse
|
34
|
Evans TJ, Ind A, Komitopoulou E, Salmond GPC. Phage-selected lipopolysaccharide mutants of Pectobacterium atrosepticum exhibit different impacts on virulence. J Appl Microbiol 2010; 109:505-514. [PMID: 20132374 DOI: 10.1111/j.1365-2672.2010.04669.x] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
AIMS To positively select Pectobacterium atrosepticum (Pa) mutants with cell surface defects and to assess the impact of these mutations on phytopathogenesis. METHODS AND RESULTS Several phages were isolated from treated sewage effluent and were found to require bacterial lipopolysaccharide (LPS) for infection. Two strains with distinct mutations in LPS were obtained by transposon mutagenesis. Along with a third LPS mutant, these strains were characterized with respect to various virulence-associated phenotypes, including growth rate, motility and exoenzyme production, demonstrating that LPS mutations are pleiotropic. Two of the strains were deficient in the synthesis of the O-antigen portion of LPS, and both were less virulent than the wild type. A waaJ mutant, which has severe defects in LPS biosynthesis, was dramatically impaired in potato tuber rot assays. The infectivity of these novel phages on 32 additional strains of Pa was tested, showing that most Pa isolates were sensitive to the LPS-dependent phages. CONCLUSIONS Native LPS is crucial for optimal growth, survival and virulence of Pa in vivo, but simultaneously renders such strains susceptible to phage infection. SIGNIFICANCE AND IMPACT OF THE STUDY This work demonstrates the power of phages to select and identify the virulence determinants on the bacterial surface, and as potential biocontrol agents for Pa infections.
Collapse
Affiliation(s)
- T J Evans
- Department of Biochemistry, University of Cambridge, Cambridge, UK
| | - A Ind
- Department of Biochemistry, University of Cambridge, Cambridge, UK
| | | | - G P C Salmond
- Department of Biochemistry, University of Cambridge, Cambridge, UK
| |
Collapse
|
35
|
Joint I. Bacterial conversations: talking, listening and eavesdropping. A NERC Discussion Meeting held at the Royal Society on 7 December 2005. J R Soc Interface 2009; 3:459-63. [PMID: 16849274 PMCID: PMC1618478 DOI: 10.1098/rsif.2006.0121] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Affiliation(s)
- Ian Joint
- Plymouth Marine Laboratory, Prospect Place,The Hoe, Plymouth, UK.
| |
Collapse
|
36
|
Gao Y, Song J, Hu B, Zhang L, Liu Q, Liu F. The luxS Gene Is Involved in AI-2 Production, Pathogenicity, and Some Phenotypes in Erwinia amylovora. Curr Microbiol 2008; 58:1-10. [DOI: 10.1007/s00284-008-9256-z] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2008] [Revised: 07/18/2008] [Accepted: 08/18/2008] [Indexed: 10/21/2022]
|
37
|
Rezzonico F, Duffy B. Lack of genomic evidence of AI-2 receptors suggests a non-quorum sensing role for luxS in most bacteria. BMC Microbiol 2008; 8:154. [PMID: 18803868 PMCID: PMC2561040 DOI: 10.1186/1471-2180-8-154] [Citation(s) in RCA: 127] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2008] [Accepted: 09/20/2008] [Indexed: 01/08/2023] Open
Abstract
Background Great excitement accompanied discoveries over the last decade in several Gram-negative and Gram-positive bacteria of the LuxS protein, which catalyzes production of the AI-2 autoinducer molecule for a second quorum sensing system (QS-2). Since the luxS gene was found to be widespread among the most diverse bacterial taxa, it was hypothesized that AI-2 may constitute the basis of a universal microbial language, a kind of bacterial Esperanto. Many of the studies published in this field have drawn a direct correlation between the occurrence of the luxS gene in a given organism and the presence and functionality of a QS-2 therein. However, rarely hathe existence of potential AI-2 receptors been examined. This is important, since it is now well recognized that LuxS also holds a central role as a metabolic enzyme in the activated methyl cycle which is responsible for the generation of S-adenosyl-L-methionine, the major methyl donor in the cell. Results In order to assess whether the role of LuxS in these bacteria is indeed related to AI-2 mediated quorum sensing we analyzed genomic databases searching for established AI-2 receptors (i.e., LuxPQ-receptor of Vibrio harveyi and Lsr ABC-transporter of Salmonella typhimurium) and other presumed QS-related proteins and compared the outcome with published results about the role of QS-2 in these organisms. An unequivocal AI-2 related behavior was restricted primarily to organisms bearing known AI-2 receptor genes, while phenotypes of luxS mutant bacteria lacking these genes could often be explained simply by assuming deficiencies in sulfur metabolism. Conclusion Genomic analysis shows that while LuxPQ is restricted to Vibrionales, the Lsr-receptor complex is mainly present in pathogenic bacteria associated with endotherms. This suggests that QS-2 may play an important role in interactions with animal hosts. In most other species, however, the role of LuxS appears to be limited to metabolism, although in a few cases the presence of yet unknown receptors or the adaptation of pre-existent effectors to QS-2 must be postulated.
Collapse
Affiliation(s)
- Fabio Rezzonico
- Agroscope Changins-Wädenswil ACW, Division of Plant Protection, CH-8820 Wädenswil, Switzerland.
| | | |
Collapse
|
38
|
Coulthurst SJ, Lilley KS, Hedley PE, Liu H, Toth IK, Salmond GPC. DsbA plays a critical and multifaceted role in the production of secreted virulence factors by the phytopathogen Erwinia carotovora subsp. atroseptica. J Biol Chem 2008; 283:23739-53. [PMID: 18562317 DOI: 10.1074/jbc.m801829200] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023] Open
Abstract
Erwinia carotovora subsp. atroseptica is an enterobacterial phytopathogen causing economically significant soft rot disease. Pathogenesis is mediated by multiple secreted virulence factors, many of which are secreted by the type II (Out) secretion system. DsbA catalyzes the introduction of disulfide bonds into periplasmic and secreted proteins. In this study, the extracellular proteome (secretome) of wild type E. carotovora subsp. atroseptica SCRI1043, and dsbA and out mutants, was analyzed by spectral counting mass spectrometry. This revealed that dsbA inactivation had a huge impact on the secretome and identified diverse DsbA- and Out-dependent secreted proteins, representing known, predicted, and novel candidate virulence factors. Further characterization of the dsbA mutant showed that secreted enzyme activities, motility, production of the quorum-sensing signal, and virulence were absent or substantially reduced. The impact of DsbA on secreted virulence factor production was mediated at multiple levels, including impacting on the Out secretion system and the virulence gene regulatory network. Transcriptome analyses revealed that the abundance of a broad, but defined, set of transcripts, including many virulence factors, was altered in the dsbA mutant, identifying a new virulence regulon responsive to extracytoplasmic conditions. In conclusion, DsbA plays a crucial, multifaceted role in the pathogenesis of E. carotovora subsp. atroseptica.
Collapse
Affiliation(s)
- Sarah J Coulthurst
- Department of Biochemistry, University of Cambridge, Tennis Court Road, Cambridge, United Kingdom
| | | | | | | | | | | |
Collapse
|
39
|
Rezzonico F, Duffy B. The role of luxS in the fire blight pathogen Erwinia amylovora is limited to metabolism and does not involve quorum sensing. MOLECULAR PLANT-MICROBE INTERACTIONS : MPMI 2007; 20:1284-1297. [PMID: 17918630 DOI: 10.1094/mpmi-20-10-1284] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
Erwinia amylovora is a gram-negative phytopathogen that causes fire blight of pome fruit and related members of the family Rosaceae. We sequenced the putative autoinducer-2 (AI-2) synthase gene luxS from E. amylovora. Diversity analysis indicated that this gene is extremely conserved among E. amylovora strains. Quorum sensing mediated by LuxS has been implicated in coordinated gene expression, growth, and virulence in other enterobacteria; however, our evidence suggests this is not the function in E. amylovora. Mutational analysis pointed to a role in colonization of apple blossoms, the primary infection court for fire blight, although little if any role in virulence on apple shoots and pear fruit was observed. Expression of key virulence genes hrpL and dspA/E was reduced in mutants of two E. amylovora strains. Stronger effects on gene expression were observed for metabolic genes involved in the activated methyl cycle with mutants having greater levels of expression. No quorum-sensing effect was observed in coculture experiments with wild-type and mutant strains either in vitro or in apple blossoms. Known receptors essential for AI-2 quorum sensing, the LuxPQ sensor kinase or the Lsr ABC-transporter, are absent in E. amylovora, further suggesting a primarily metabolic role for luxS in this bacterium.
Collapse
Affiliation(s)
- Fabio Rezzonico
- SafeCrop Centre, Istituto Agrario di S. Michele all'Adige, 38010 S. Michele all'Adige, Italy.
| | | |
Collapse
|
40
|
Fineran PC, Williamson NR, Lilley KS, Salmond GPC. Virulence and prodigiosin antibiotic biosynthesis in Serratia are regulated pleiotropically by the GGDEF/EAL domain protein, PigX. J Bacteriol 2007; 189:7653-62. [PMID: 17766413 PMCID: PMC2168757 DOI: 10.1128/jb.00671-07] [Citation(s) in RCA: 61] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
Gram-negative bacteria of the genus Serratia are opportunistic human, plant, and insect pathogens. Serratia sp. strain ATCC 39006 secretes pectinases and cellulases and produces the secondary metabolites carbapenem and prodigiosin. Mutation of a gene (pigX) resulted in an extremely pleiotropic phenotype: prodigiosin antibiotic biosynthesis, plant virulence, and pectinase production were all elevated. PigX controlled secondary metabolism by repressing the transcription of the target prodigiosin biosynthetic operon (pigA-pigO). The transcriptional start site of pigX was determined, and pigX expression occurred in parallel with Pig production. Detailed quantitative intracellular proteome analyses enabled the identification of numerous downstream targets of PigX, including OpgG, mutation of which reduced the production of the plant cell wall-degrading enzymes and virulence. The highly pleiotropic PigX regulator contains GGDEF and EAL domains with noncanonical motifs and is predicted to be membrane associated. Genetic evidence suggests that PigX might function as a cyclic dimeric GMP phosphodiesterase. This is the first characterization of a GGDEF and EAL domain protein in Serratia and the first example of the regulation of antibiotic production by a GGDEF/EAL domain protein.
Collapse
Affiliation(s)
- Peter C Fineran
- Department of Biochemistry, Tennis Court Road, University of Cambridge, Cambridge CB2 1QW, United Kingdom
| | | | | | | |
Collapse
|
41
|
Mattinen L, Nissinen R, Riipi T, Kalkkinen N, Pirhonen M. Host-extract induced changes in the secretome of the plant pathogenic bacterium
Pectobacterium atrosepticum. Proteomics 2007; 7:3527-37. [PMID: 17726675 DOI: 10.1002/pmic.200600759] [Citation(s) in RCA: 73] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
Pectobacterium atrosepticum is a Gram-negative plant pathogenic bacterium that causes rotting in potato stems and tubers. The secreted proteins of this pathogen were analyzed with proteomics from culture supernatant of cells grown in minimal medium supplemented with host extracts. More than 40 proteins were identified, among them known virulence determinants, such as pectic enzymes, metalloprotease, and virulence protein Svx, along with flagella proteins, GroEL and cyclophilin-type chaperones and several hypothetical proteins or proteins with unknown function. Some of the identified proteins may be involved in utilization of nutrients or transport of minerals. Northern and real-time RT-PCR analyses suggested that most of the proteins upregulated by plant extract were transcriptionally regulated. Among the identified proteins were VgrG and four homologs of hemolysin-coregulated proteins (Hcps). A mutant strain lacking one of the hcp genes was not affected in virulence, while a bacterial strain overexpressing the same gene was shown to have increased virulence, which suggests that these proteins may be new virulence determinants of P. atrosepticum. Comparison of the secretomes of wild type cells and hrcC mutant defective in Type III secretion suggested that the production of the identified proteins was independent of functional Type III secretion system.
Collapse
Affiliation(s)
- Laura Mattinen
- Department of Applied Biology, University of Helsinki, Finland
| | | | | | | | | |
Collapse
|
42
|
Karp NA, McCormick PS, Russell MR, Lilley KS. Experimental and Statistical Considerations to Avoid False Conclusions in Proteomics Studies Using Differential In-gel Electrophoresis. Mol Cell Proteomics 2007; 6:1354-64. [PMID: 17513293 DOI: 10.1074/mcp.m600274-mcp200] [Citation(s) in RCA: 140] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
In quantitative proteomics, the false discovery rate (FDR) can be defined as the number of false positives within statistically significant changes in expression. False positives accumulate during the simultaneous testing of expression changes across hundreds or thousands of protein or peptide species when univariate tests such as the Student's t test are used. Currently most researchers rely solely on the estimation of p values and a significance threshold, but this approach may result in false positives because it does not account for the multiple testing effect. For each species, a measure of significance in terms of the FDR can be calculated, producing individual q values. The q value maintains power by allowing the investigator to achieve an acceptable level of true or false positives within the calls of significance. The q value approach relies on the use of the correct statistical test for the experimental design. In this situation, a uniform p value frequency distribution when there are no differences in expression between two samples should be obtained. Here we report a bias in p value distribution in the case of a three-dye DIGE experiment where no changes in expression are occurring. The bias was shown to arise from correlation in the data from the use of a common internal standard. With a two-dye schema, where each sample has its own internal standard, such bias was removed, enabling the application of the q value to two different proteomics studies. In the case of the first study, we demonstrate that 80% of calls of significance by the more traditional method are false positives. In the second, we show that calculating the q value gives the user control over the FDR. These studies demonstrate the power and ease of use of the q value in correcting for multiple testing. This work also highlights the need for robust experimental design that includes the appropriate application of statistical procedures.
Collapse
Affiliation(s)
- Natasha A Karp
- Department of Biochemistry, University of Cambridge, Building O, Downing Site, Cambridge CB2 1QW, United Kingdom
| | | | | | | |
Collapse
|
43
|
Barnard AM, Bowden SD, Burr T, Coulthurst SJ, Monson RE, Salmond GP. Quorum sensing, virulence and secondary metabolite production in plant soft-rotting bacteria. Philos Trans R Soc Lond B Biol Sci 2007; 362:1165-83. [PMID: 17360277 PMCID: PMC2435580 DOI: 10.1098/rstb.2007.2042] [Citation(s) in RCA: 104] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
Quorum sensing describes the ability of bacteria to sense their population density and respond by modulating gene expression. In the plant soft-rotting bacteria, such as Erwinia, an arsenal of plant cell wall-degrading enzymes is produced in a cell density-dependent manner, which causes maceration of plant tissue. However, quorum sensing is central not only to controlling the production of such destructive enzymes, but also to the control of a number of other virulence determinants and secondary metabolites. Erwinia synthesizes both N-acylhomoserine lactone (AHL) and autoinducer-2 types of quorum sensing signal, which both play a role in regulating gene expression in the phytopathogen. We review the models for AHL-based regulation of carbapenem antibiotic production in Erwinia. We also discuss the importance of quorum sensing in the production and secretion of virulence determinants by Erwinia, and its interplay with other regulatory systems.
Collapse
Affiliation(s)
| | | | | | | | | | - George P.C Salmond
- Department of Biochemistry, University of CambridgeTennis Court Road, Cambridge CB2 1QW, UK
| |
Collapse
|
44
|
Mohammadi M, Geider K. Autoinducer-2 of the fire blight pathogen Erwinia amylovora and other plant-associated bacteria. FEMS Microbiol Lett 2007; 266:34-41. [PMID: 17092294 DOI: 10.1111/j.1574-6968.2006.00510.x] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022] Open
Abstract
Autoinducers are important for cellular communication of bacteria. The luxS gene has a central role in the synthesis of autoinducer-2 (AI-2). The gene was identified in a shotgun library of Erwinia amylovora and primers designed for PCR amplification from bacterial DNA. Supernatants of several Erwinia amylovora strains were assayed for AI-2 activity with a Vibrio harveyi mutant and were positive. Many other plant-associated bacteria also showed AI-2 activity such as Erwinia pyrifoliae and Erwinia tasmaniensis. The luxS genes of several bacteria were cloned, sequenced, and complemented Escherichia coli strain DH5alpha and a Salmonella typhimurium mutant, both defective in luxS, for synthesis of AI-2. Assays to detect AI-2 activity in culture supernatants of several Pseudomonas syringae pathovars failed, which may indicate the absence of AI-2 or synthesis of another type. Several reporter strains did not detect synthesis of an acyl homoserine lactone (AHL, AI-1) by Erwinia amylovora, but confirmed AHL-synthesis for Erwinia carotovora ssp. atroseptica and Pantoea stewartii.
Collapse
Affiliation(s)
- Mojtaba Mohammadi
- Federal Biological Research Centre for Agriculture and Forestry (BBA), Dossenheim, Germany
| | | |
Collapse
|
45
|
Siepen JA, Swainston N, Jones AR, Hart SR, Hermjakob H, Jones P, Hubbard SJ. An informatic pipeline for the data capture and submission of quantitative proteomic data using iTRAQ. Proteome Sci 2007; 5:4. [PMID: 17270041 PMCID: PMC1796855 DOI: 10.1186/1477-5956-5-4] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2006] [Accepted: 02/01/2007] [Indexed: 01/25/2023] Open
Abstract
Background Proteomics continues to play a critical role in post-genomic science as continued advances in mass spectrometry and analytical chemistry support the separation and identification of increasing numbers of peptides and proteins from their characteristic mass spectra. In order to facilitate the sharing of this data, various standard formats have been, and continue to be, developed. Still not fully mature however, these are not yet able to cope with the increasing number of quantitative proteomic technologies that are being developed. Results We propose an extension to the PRIDE and mzData XML schema to accommodate the concept of multiple samples per experiment, and in addition, capture the intensities of the iTRAQTM reporter ions in the entry. A simple Java-client has been developed to capture and convert the raw data from common spectral file formats, which also uses a third-party open source tool for the generation of iTRAQTM reported intensities from Mascot output, into a valid PRIDE XML entry. Conclusion We describe an extension to the PRIDE and mzData schemas to enable the capture of quantitative data. Currently this is limited to iTRAQTM data but is readily extensible for other quantitative proteomic technologies. Furthermore, a software tool has been developed which enables conversion from various mass spectrum file formats and corresponding Mascot peptide identifications to PRIDE formatted XML. The tool represents a simple approach to preparing quantitative and qualitative data for submission to repositories such as PRIDE, which is necessary to facilitate data deposition and sharing in public domain database. The software is freely available from .
Collapse
Affiliation(s)
| | - Neil Swainston
- Manchester Interdisciplinary Biocentre, University of Manchester, UK
| | - Andrew R Jones
- Faculty of Life Sciences, University of Manchester, M13 9PT, UK
- School of Computer Science, Faculty of Engineering and Physical Sciences, University of Manchester, UK
| | - Sarah R Hart
- MBCMS, School of Chemistry, Manchester Interdisciplinary Biocentre, University of Manchester, UK
| | - Henning Hermjakob
- EMBL Outstation EBI, Wellcome Trust Genome Campus, Hinxton, Cambs, UK
| | - Philip Jones
- EMBL Outstation EBI, Wellcome Trust Genome Campus, Hinxton, Cambs, UK
| | - Simon J Hubbard
- Faculty of Life Sciences, University of Manchester, M13 9PT, UK
| |
Collapse
|
46
|
Barnard AML, Salmond GPC. Quorum sensing in Erwinia species. Anal Bioanal Chem 2006; 387:415-23. [PMID: 16943991 DOI: 10.1007/s00216-006-0701-1] [Citation(s) in RCA: 99] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2006] [Revised: 07/19/2006] [Accepted: 07/20/2006] [Indexed: 01/01/2023]
Abstract
The term quorum sensing (QS) refers to the ability of bacteria to regulate gene expression according to the accumulation of signalling molecules that are made by every cell in the population. The erwiniae group of bacteria are often phytopathogens and the expression of a number of their important virulence determinants and secondary metabolites is under QS control. The erwiniae utilise two types of QS signalling molecules: N-acyl homoserine lactones and AI-2-type signalling molecules. Here, we review the regulatory networks involving QS in the soft rot erwiniae.
Collapse
Affiliation(s)
- Anne M L Barnard
- Department of Biochemistry, University of Cambridge, Tennis Court Road, Cambridge, CB2 1QW, UK
| | | |
Collapse
|
47
|
Coulthurst SJ, Williamson NR, Harris AKP, Spring DR, Salmond GPC. Metabolic and regulatory engineering of Serratia marcescens: mimicking phage-mediated horizontal acquisition of antibiotic biosynthesis and quorum-sensing capacities. MICROBIOLOGY-SGM 2006; 152:1899-1911. [PMID: 16804166 DOI: 10.1099/mic.0.28803-0] [Citation(s) in RCA: 65] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
Serratia marcescens is an important cause of opportunistic human infections. Many, but not all, strains produce prodigiosin, a secondary metabolic, red-pigment antibiotic, the biosynthesis of which is directed by the pig gene cluster. Quorum sensing (QS) involves the production and detection of chemical signal molecules as a means to regulate gene expression in response to population cell density. Several strains of S. marcescens have previously been shown to possess an N-acyl-L-homoserine lactone (aHSL) QS system. This study aimed to determine the impact of introducing, by phage-mediated horizontal gene transfer, a biosynthetic gene cluster (pig) and a regulatory locus (aHSL QS) into strains lacking the respective trait. The pig cluster from S. marcescens ATCC 274 (Sma 274) was transferred to the non-pigmented strain, S. marcescens strain 12 (Sma 12). In the engineered strain, pigment was expressed and brought under the control of the recipient's native regulatory systems (aHSL QS and luxS). Moreover, transfer of the aHSL locus from Sma 12 to the non-QS Sma 274 resulted in the imposition of aHSL control onto a variety of native traits, including pigment production. In addition, during this study, the QS regulon of the clinical strain, Sma 12, was characterized, and some novel QS-regulated traits in S. marcescens were identified. The results have implications for the evolution and dissemination of biosynthetic and QS loci, illustrating the genetic modularity and ease of acquisition of these traits and the capacity of phages to act as vectors for horizontal gene transfer.
Collapse
Affiliation(s)
- Sarah J Coulthurst
- Department of Biochemistry, University of Cambridge, Tennis Court Road, Cambridge CB2 1QW, UK
| | - Neil R Williamson
- Department of Biochemistry, University of Cambridge, Tennis Court Road, Cambridge CB2 1QW, UK
| | - Abigail K P Harris
- Department of Biochemistry, University of Cambridge, Tennis Court Road, Cambridge CB2 1QW, UK
| | - David R Spring
- Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge CB2 1EW, UK
| | - George P C Salmond
- Department of Biochemistry, University of Cambridge, Tennis Court Road, Cambridge CB2 1QW, UK
| |
Collapse
|
48
|
Toth IK, Pritchard L, Birch PRJ. Comparative genomics reveals what makes an enterobacterial plant pathogen. ANNUAL REVIEW OF PHYTOPATHOLOGY 2006; 44:305-36. [PMID: 16704357 DOI: 10.1146/annurev.phyto.44.070505.143444] [Citation(s) in RCA: 97] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/09/2023]
Abstract
The bacterial family Enterobacteriaceae contains some of the most devastating human and animal pathogens, including Escherichia coli, Salmonella enterica and species of Yersinia and Shigella. These are among the best-studied of any organisms, yet there is much to be learned about the nature and evolution of interactions with their hosts and with the wider environment. Comparative and functional genomics have fundamentally improved our understanding of their modes of adaptation to different ecological niches and the genes that determine their pathogenicity. In addition to animal pathogens, Enterobacteriaceae include important plant pathogens, such as Erwinia carotovora subsp. atroseptica (Eca), the first plant-pathogenic enterobacterium to be sequenced. This review focuses on genomic comparisons between Eca and other enterobacteria, with particular emphasis on the differences that exemplify or explain the plant-associated lifestyle(s) of Eca. Horizontal gene transfer in Eca may directly have led to the acquisition of a number of determinants that mediate its interactions, pathogenic or otherwise, with plants, offering a glimpse into its evolutionary divergence from animal-pathogenic enterobacteria.
Collapse
Affiliation(s)
- Ian K Toth
- Plant Pathology Program, Scottish Crop Research Institute, Invergowrie, Dundee DD2 5DA, United Kingdom.
| | | | | |
Collapse
|