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Alexandrino AV, Barcelos MP, Federico LB, da Silva TG, Cavalca LB, de Moraes CHA, Ferreira H, Taft CA, Behlau F, de Paula Silva CHT, Novo-Mansur MTM. GDP-mannose pyrophosphorylase is an efficient target in Xanthomonas citri for citrus canker control. Microbiol Spectr 2024; 12:e0367323. [PMID: 38722158 PMCID: PMC11237706 DOI: 10.1128/spectrum.03673-23] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2023] [Accepted: 03/20/2024] [Indexed: 06/06/2024] Open
Abstract
Xanthomonas citri subsp. citri (Xcc) is a bacterium that causes citrus canker, an economically important disease that results in premature fruit drop and reduced yield of fresh fruit. In this study, we demonstrated the involvement of XanB, an enzyme with phosphomannose isomerase (PMI) and guanosine diphosphate-mannose pyrophosphorylase (GMP) activities, in Xcc pathogenicity. Additionally, we found that XanB inhibitors protect the host against Xcc infection. Besides being deficient in motility, biofilm production, and ultraviolet resistance, the xanB deletion mutant was unable to cause disease, whereas xanB complementation restored wild-type phenotypes. XanB homology modeling allowed in silico virtual screening of inhibitors from databases, three of them being suitable in terms of absorption, distribution, metabolism, excretion, and toxicity (ADME/Tox) properties, which inhibited GMP (but not PMI) activity of the Xcc recombinant XanB protein in more than 50%. Inhibitors reduced citrus canker severity up to 95%, similarly to copper-based treatment. xanB is essential for Xcc pathogenicity, and XanB inhibitors can be used for the citrus canker control. IMPORTANCE Xcc causes citrus canker, a threat to citrus production, which has been managed with copper, being required a more sustainable alternative for the disease control. XanB was previously found on the surface of Xcc, interacting with the host and displaying PMI and GMP activities. We demonstrated by xanB deletion and complementation that GMP activity plays a critical role in Xcc pathogenicity, particularly in biofilm formation. XanB homology modeling was performed, and in silico virtual screening led to carbohydrate-derived compounds able to inhibit XanB activity and reduce disease symptoms by 95%. XanB emerges as a promising target for drug design for control of citrus canker and other economically important diseases caused by Xanthomonas sp.
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Affiliation(s)
- André Vessoni Alexandrino
- Laboratório de Bioquímica e Biologia Molecular Aplicada (LBBMA), Departamento de Genética e Evolução, Universidade Federal de São Carlos, São Carlos, São Paulo, Brazil
- Programa de Pós-Graduação em Biotecnologia (PPGBiotec), Universidade Federal de São Carlos, São Carlos, São Paulo, Brazil
| | - Mariana Pegrucci Barcelos
- Faculdade de Ciências Farmacêuticas de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, São Paulo, Brazil
| | - Leonardo Bruno Federico
- Faculdade de Ciências Farmacêuticas de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, São Paulo, Brazil
| | - Tamiris Garcia da Silva
- Departamento de Pesquisa e Desenvolvimento, Fundo de Defesa da Citricultura, Fundecitrus, Araraquara, São Paulo, Brazil
| | - Lúcia Bonci Cavalca
- Departamento de Bioquímica e Microbiologia, Instituto de Biociências, UNESP, Universidade Estadual Paulista, Rio Claro, São Paulo, Brazil
| | - Carlos Henrique Alves de Moraes
- Laboratório de Bioquímica e Biologia Molecular Aplicada (LBBMA), Departamento de Genética e Evolução, Universidade Federal de São Carlos, São Carlos, São Paulo, Brazil
| | - Henrique Ferreira
- Departamento de Bioquímica e Microbiologia, Instituto de Biociências, UNESP, Universidade Estadual Paulista, Rio Claro, São Paulo, Brazil
| | | | - Franklin Behlau
- Departamento de Pesquisa e Desenvolvimento, Fundo de Defesa da Citricultura, Fundecitrus, Araraquara, São Paulo, Brazil
| | | | - Maria Teresa Marques Novo-Mansur
- Laboratório de Bioquímica e Biologia Molecular Aplicada (LBBMA), Departamento de Genética e Evolução, Universidade Federal de São Carlos, São Carlos, São Paulo, Brazil
- Programa de Pós-Graduação em Biotecnologia (PPGBiotec), Universidade Federal de São Carlos, São Carlos, São Paulo, Brazil
- Programa de Pós-Graduação em Genética Evolutiva e Biologia Molecular (PPGGEv), Universidade Federal de São Carlos, São Carlos, São Paulo, Brazil
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Carrau A, Tano J, Moyano L, Ripa MB, Petrocelli S, Piskulic L, Moreira LM, Patané JSL, Setubal JC, Orellano EG. A novel BLUF photoreceptor modulates the Xanthomonas citri subsp. citri-host plant interaction. Photochem Photobiol Sci 2023; 22:1901-1918. [PMID: 37209300 DOI: 10.1007/s43630-023-00420-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2023] [Accepted: 04/05/2023] [Indexed: 05/22/2023]
Abstract
Plant-pathogen interaction is influenced by multiple environmental factors, including temperature and light. Recent works have shown that light modulates not only the defense response of plants but also the pathogens virulence. Xanthomonas citri subsp. citri (Xcc) is the bacterium responsible for citrus canker, an important plant disease worldwide. The Xcc genome presents four genes encoding putative photoreceptors: one bacteriophytochrome and three blue light photoreceptors, one LOV and two BLUFs (bluf1: XAC2120 and bluf2: XAC3278). The presence of two BLUFs proteins is an outstanding feature of Xcc. In this work we show that the bluf2 gene is functional. The mutant strain, XccΔbluf2, was constructed demonstrating that BLUF2 regulates swimming-type motility, adhesion to leaves, exopolysaccharide production and biofilm formation, features involved in the Xcc virulence processes. An important aspect during the plant-pathogen interaction is the oxidative response of the host and the consequent reaction of the pathogen. We observed that ROS detoxification is regulated by Xcc bluf2 gene. The phenotypes of disease in orange plants produced by WT and XccΔbluf2 strains were evaluated, observing different phenotypes. Altogether, these results show that BLUF2 negatively regulates virulence during citrus canker. This work constitutes the first report on BLUF-like receptors in plant pathogenic bacteria.
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Affiliation(s)
- Analía Carrau
- Instituto de Biología Molecular y Celular de Rosario, Consejo Nacional de Investigaciones Científicas y Técnicas, Facultad de Ciencias Bioquímicas y Farmacéuticas, Universidad Nacional de Rosario, Suipacha 531, S2002LRK, Rosario, Argentina
| | - Josefina Tano
- Instituto de Biología Molecular y Celular de Rosario, Consejo Nacional de Investigaciones Científicas y Técnicas, Facultad de Ciencias Bioquímicas y Farmacéuticas, Universidad Nacional de Rosario, Suipacha 531, S2002LRK, Rosario, Argentina
| | - Laura Moyano
- Universidad de Buenos Aires, Facultad de Ciencias Exactas y Naturales, Departamento de Biodiversidad y Biología Experimental, Buenos Aires, Argentina
- Instituto de Biodiversidad y Biología Experimental y Aplicada, Consejo Nacional de Investigaciones Científicas y Técnicas-Universidad de Buenos Aires (IBBEA, CONICET-UBA), Buenos Aires, Argentina
| | - María Belén Ripa
- Instituto de Biología Molecular y Celular de Rosario, Consejo Nacional de Investigaciones Científicas y Técnicas, Facultad de Ciencias Bioquímicas y Farmacéuticas, Universidad Nacional de Rosario, Suipacha 531, S2002LRK, Rosario, Argentina
| | - Silvana Petrocelli
- Facultad de Ciencias Bioquímicas y Farmacéuticas, Universidad Nacional de Rosario, Suipacha 531, S2002LRK, Rosario, Argentina
| | - Laura Piskulic
- Área Estadística y Procesamiento de Datos, Facultad de Ciencias Bioquímicas y Farmacéuticas, Universidad Nacional de Rosario, Rosario, Argentina
| | - Leandro Marcio Moreira
- Programa de Pós-Graduação em Biotecnologia, Núcleo de Pesquisas em Ciências Biológicas, Universidade Federal de Ouro Preto, Ouro Preto, MG, Brazil
- Departamento de Ciências Biológicas, Instituto de Ciências Exatas e Biológicas, Universidade Federal de Ouro Preto, Ouro Preto, MG, Brazil
| | | | | | - Elena Graciela Orellano
- Instituto de Biología Molecular y Celular de Rosario, Consejo Nacional de Investigaciones Científicas y Técnicas, Facultad de Ciencias Bioquímicas y Farmacéuticas, Universidad Nacional de Rosario, Suipacha 531, S2002LRK, Rosario, Argentina.
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3
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Shao Y, Tang G, Huang Y, Ke W, Wang S, Zheng D, Ruan L. Transcriptional regulator Sar regulates the multiple secretion systems in Xanthomonas oryzae. MOLECULAR PLANT PATHOLOGY 2023; 24:16-27. [PMID: 36177860 PMCID: PMC9742495 DOI: 10.1111/mpp.13272] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/12/2022] [Revised: 08/24/2022] [Accepted: 08/24/2022] [Indexed: 06/16/2023]
Abstract
Xanthomonas oryzae pv. oryzae (Xoo) is a notorious plant pathogen that causes leaf blight of rice cultivars. The pathogenic bacteria possess numerous transcriptional regulators to regulate various biological processes, such as pathogenicity in the host plant. Our previous study identified a new master regulator PXO_RS20790 that is involved in pathogenicity for Xoo against the host rice. However, the molecular functions of PXO_RS20790 are still unclear. Here, we demonstrate that transcriptional regulator Sar (PXO_RS20790) regulates multiple secretion systems. The RNA-sequencing analysis, bacterial one-hybrid assay, and electrophoretic mobility shift assay revealed that Sar enables binding of the promoters of the T1SS-related genes, the avirulence gene, raxX, and positively regulates these genes' expression. Meanwhile, we found that Sar positively regulated the T6SS-1 clusters but did not regulate the T6SS-2 clusters. Furthermore, we revealed that only T6SS-2 is involved in interbacterial competition. We also indicated that Sar could bind the promoters of the T3SS regulators, hrpG and hrpX, to activate these two genes' transcription. Our findings revealed that Sar is a crucial regulator of multiple secretion systems and virulence.
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Affiliation(s)
- Yanan Shao
- State Key Laboratory of Agricultural Microbiology, College of Life Science and TechnologyHuazhong Agricultural UniversityWuhanChina
| | - Guiyu Tang
- State Key Laboratory of Agricultural Microbiology, College of Life Science and TechnologyHuazhong Agricultural UniversityWuhanChina
| | - Yuanyuan Huang
- State Key Laboratory of Agricultural Microbiology, College of Life Science and TechnologyHuazhong Agricultural UniversityWuhanChina
| | - Wenli Ke
- State Key Laboratory of Agricultural Microbiology, College of Life Science and TechnologyHuazhong Agricultural UniversityWuhanChina
| | - Shasha Wang
- State Key Laboratory of Agricultural Microbiology, College of Life Science and TechnologyHuazhong Agricultural UniversityWuhanChina
| | - Dehong Zheng
- State Key Laboratory of Agricultural Microbiology, College of Life Science and TechnologyHuazhong Agricultural UniversityWuhanChina
- National Demonstration Center for Experimental Plant Science Education, College of AgricultureGuangxi UniversityNanningChina
| | - Lifang Ruan
- State Key Laboratory of Agricultural Microbiology, College of Life Science and TechnologyHuazhong Agricultural UniversityWuhanChina
- College of Resources and EnvironmentTibet Agriculture & Animal Husbandry UniversityLinzhiChina
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A Pan-Global Study of Bacterial Leaf Spot of Chilli Caused by Xanthomonas spp. PLANTS 2022; 11:plants11172291. [PMID: 36079673 PMCID: PMC9460788 DOI: 10.3390/plants11172291] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/24/2022] [Revised: 08/22/2022] [Accepted: 08/26/2022] [Indexed: 11/17/2022]
Abstract
Bacterial Leaf Spot (BLS) is a serious bacterial disease of chilli (Capsicum spp.) caused by at least four different Xanthomonas biotypes: X. euvesicatoria pv. euvesicatoria, X. euvesicatoria pv. perforans, X. hortorum pv. gardneri, and X. vesicatoria. Symptoms include black lesions and yellow halos on the leaves and fruits, resulting in reports of up to 66% losses due to unsalable and damaged fruits. BLS pathogens are widely distributed in tropical and subtropical regions. Xanthomonas is able to survive in seeds and crop residues for short periods, leading to the infections in subsequent crops. The pathogen can be detected using several techniques, but largely via a combination of traditional and molecular approaches. Conventional detection is based on microscopic and culture observations, while a suite of Polymerase Chain Reaction (PCR) and Loop-Mediated Isothermal Amplification (LAMP) assays are available. Management of BLS is challenging due to the broad genetic diversity of the pathogens, a lack of resilient host resistance, and poor efficacy of chemical control. Some biological control agents have been reported, including bacteriophage deployment. Incorporating stable host resistance is a critical component in ongoing integrated management for BLS. This paper reviews the current status of BLS of chilli, including its distribution, pathogen profiles, diagnostic options, disease management, and the pursuit of plant resistance.
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Liu M, Tian Y, Zaki HEM, Ahmed T, Yao R, Yan C, Leptihn S, Loh B, Shahid MS, Wang F, Chen J, Li B. Phage Resistance Reduced the Pathogenicity of Xanthomonas oryzae pv. oryzae on Rice. Viruses 2022; 14:v14081770. [PMID: 36016392 PMCID: PMC9416502 DOI: 10.3390/v14081770] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2022] [Revised: 08/10/2022] [Accepted: 08/10/2022] [Indexed: 11/16/2022] Open
Abstract
Plants grow together with microbes that have both negative and positive impacts on the host, while prokaryotes are in turn also hosts for viruses, co-evolving together in a complex interrelationship. Most research focuses on the interaction of either bacterial pathogens interacting with the plant host, or the impact on viruses on their pathogenic bacterial hosts. Few studies have investigated the co-evolution of bacterial pathogens with their host plants as well as with their bacterial viruses. In this work, we aimed to identify the genes that were associated with both phage sensitivity and host pathogenicity of the bacterium Xanthomonas oryzae pv. oryzae (Xoo), which is the most important bacterial rice pathogen. Using the Tn5 transposon mutation technology, we created a library of Xoo strain C2 comprising 4524 mutants, which were subsequently tested for phage infectability. The phage infection tests showed that less than 1% of the mutants (n = 36) were resistant to phage infection, which was attributed to the Tn5 insertion in 19 genes. Interestingly, three out of 19 genes that conveyed resistance to the phage resulted in reduced pathogenicity to rice seedlings compared to the wild type. We identified three genes involved in both phage infection and bacterial virulence, which were studied by knockout mutants and complementation experiments. All of the three knockout mutants were resistant to infection by phage X2, while the complemented strains restored the susceptibility to the bacterial virus. Surprisingly, the genes are also essential for pathogenicity, which we confirmed by single knockout mutants corresponding to the Tn5 mutants. All three genes are involved in lipopolysaccharide synthesis, thus changing the cell envelope surface molecule composition. Our work shows a possible balance in terms of the connection between bacterial virulence and phage resistance, supporting the deployment of phages for the biocontrol of plant pathogens.
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Affiliation(s)
- Mengju Liu
- State Key Laboratory of Rice Biology, and Ministry of Agriculture Key Laboratory of Molecular Biology of Crop Pathogens and Insects, and Key Laboratory of Biology of Crop Pathogens and Insects of Zhejiang Province, Institute of Biotechnology, Zhejiang University, Hangzhou 310058, China
| | - Ye Tian
- State Key Laboratory of Rice Biology, and Ministry of Agriculture Key Laboratory of Molecular Biology of Crop Pathogens and Insects, and Key Laboratory of Biology of Crop Pathogens and Insects of Zhejiang Province, Institute of Biotechnology, Zhejiang University, Hangzhou 310058, China
| | - Haitham E. M. Zaki
- Horticulture Department, Faculty of Agriculture, Minia University, El-Minia 61517, Egypt
- Applied Biotechnology Department, University of Technology and Applied Sciences-Sur, Sur 411, Oman
| | - Temoor Ahmed
- State Key Laboratory of Rice Biology, and Ministry of Agriculture Key Laboratory of Molecular Biology of Crop Pathogens and Insects, and Key Laboratory of Biology of Crop Pathogens and Insects of Zhejiang Province, Institute of Biotechnology, Zhejiang University, Hangzhou 310058, China
| | - Rong Yao
- State Key Laboratory of Rice Biology, and Ministry of Agriculture Key Laboratory of Molecular Biology of Crop Pathogens and Insects, and Key Laboratory of Biology of Crop Pathogens and Insects of Zhejiang Province, Institute of Biotechnology, Zhejiang University, Hangzhou 310058, China
| | - Chengqi Yan
- Institute of Biotechnology, Ningbo Academy of Agricultural Sciences, Ningbo 315040, China
| | - Sebastian Leptihn
- University of Edinburgh Institute, Zhejiang University, Hangzhou 314400, China
| | - Belinda Loh
- Fraunhofer Institute for Cell Therapy & Immunology (IZI), Department of Vaccines and Infection Models, Perlickstr. 1, 04103 Leipzig, Germany
| | - Muhammad Shafiq Shahid
- Department of Plant Sciences, College of Agricultural and Marine Sciences, Sultan Qaboos University, Al-khod 123, Oman
| | - Fang Wang
- Institute of Biotechnology, Ningbo Academy of Agricultural Sciences, Ningbo 315040, China
- Correspondence: (F.W.); (J.C.); (B.L.) Tel.: +86-0571-88982412 (B.L.)
| | - Jianping Chen
- State Key Laboratory for Managing Biotic and Chemical Threats to the Quality and Safety of Agro-Products, Key Laboratory of Biotechnology in Plant Protection of Ministry of Agriculture and Zhejiang Province, Institute of Plant Virology, Ningbo University, Ningbo 315211, China
- Correspondence: (F.W.); (J.C.); (B.L.) Tel.: +86-0571-88982412 (B.L.)
| | - Bin Li
- State Key Laboratory of Rice Biology, and Ministry of Agriculture Key Laboratory of Molecular Biology of Crop Pathogens and Insects, and Key Laboratory of Biology of Crop Pathogens and Insects of Zhejiang Province, Institute of Biotechnology, Zhejiang University, Hangzhou 310058, China
- Correspondence: (F.W.); (J.C.); (B.L.) Tel.: +86-0571-88982412 (B.L.)
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Long Y, Luo R, Xu Z, Cheng S, Li L, Ma H, Bao M, Li M, Ouyang Z, Wang N, Duan S. A Fluorescent Reporter-Based Evaluation Assay for Antibacterial Components Against Xanthomonas citri subsp. citri. Front Microbiol 2022; 13:864963. [PMID: 35602035 PMCID: PMC9114712 DOI: 10.3389/fmicb.2022.864963] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2022] [Accepted: 04/05/2022] [Indexed: 11/13/2022] Open
Abstract
Xanthomonas citri subsp. citri (Xcc) is the agent of citrus bacterial canker (CBC) disease, which has significantly reduced citrus quantity and quality in many producing areas worldwide. Copper-based bactericides are the primary products for CBC control and management, but the problems derived from copper-resistant and environmental contamination have become issues of anxiety. Thus, there is a need to find alternative antibacterial products instead of relying on a single type of agent. This study developed a method to evaluate the inhibition of antibacterial agents using the fluorescence-labeled recombinant Xcc strain (Xcc-eYFP). The optimization of timelines and parameters for the evaluation of antibacterial agents involved the use of a Spark™ multimode microplate reader. This evaluation and screening method can be applied to bactericides, cocktail-mixture formulations, antagonistic bacteria, and derived metabolites. The results showed that the minimum inhibitory concentration (MIC) of commercial bactericides determined by fluorescence agrees with the MIC values determined by the conventional method. A screened cocktail-mixture bactericide presents more activity than the individual agents during the protective effects. Notably, this method has been further developed in the screening of Xcc-antagonistic bacterial strains. In summary, we provide a validated strategy for screening and evaluation of different antibacterial components for inhibition against Xcc for CBC control and management.
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Affiliation(s)
- Yunfei Long
- China-USA Citrus Huanglongbing Joint Laboratory, National Navel Orange Engineering Research Center, Gannan Normal University, Ganzhou, China
| | - Ruifang Luo
- China-USA Citrus Huanglongbing Joint Laboratory, National Navel Orange Engineering Research Center, Gannan Normal University, Ganzhou, China
| | - Zhou Xu
- China-USA Citrus Huanglongbing Joint Laboratory, National Navel Orange Engineering Research Center, Gannan Normal University, Ganzhou, China
| | - Shuyuan Cheng
- China-USA Citrus Huanglongbing Joint Laboratory, National Navel Orange Engineering Research Center, Gannan Normal University, Ganzhou, China
| | - Ling Li
- China-USA Citrus Huanglongbing Joint Laboratory, National Navel Orange Engineering Research Center, Gannan Normal University, Ganzhou, China
| | - Haijie Ma
- College of Agricultural and Food Sciences, Zhejiang A&F University, Hangzhou, China
| | - Minli Bao
- China-USA Citrus Huanglongbing Joint Laboratory, National Navel Orange Engineering Research Center, Gannan Normal University, Ganzhou, China
| | - Min Li
- China-USA Citrus Huanglongbing Joint Laboratory, National Navel Orange Engineering Research Center, Gannan Normal University, Ganzhou, China
| | - Zhigang Ouyang
- China-USA Citrus Huanglongbing Joint Laboratory, National Navel Orange Engineering Research Center, Gannan Normal University, Ganzhou, China
| | - Nian Wang
- Department of Microbiology and Cell Science, Citrus Research and Education Center, University of Florida, Lake Alfred, FL, United States
| | - Shuo Duan
- China-USA Citrus Huanglongbing Joint Laboratory, National Navel Orange Engineering Research Center, Gannan Normal University, Ganzhou, China
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Morinière L, Mirabel L, Gueguen E, Bertolla F. A Comprehensive Overview of the Genes and Functions Required for Lettuce Infection by the Hemibiotrophic Phytopathogen Xanthomonas hortorum pv. vitians. mSystems 2022; 7:e0129021. [PMID: 35311560 PMCID: PMC9040725 DOI: 10.1128/msystems.01290-21] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2021] [Accepted: 02/07/2022] [Indexed: 12/25/2022] Open
Abstract
The successful infection of a host plant by a phytopathogenic bacterium depends on a finely tuned molecular cross talk between the two partners. Thanks to transposon insertion sequencing techniques (Tn-seq), whole genomes can now be assessed to determine which genes are important for the fitness of several plant-associated bacteria in planta. Despite its agricultural relevance, the dynamic molecular interaction established between the foliar hemibiotrophic phytopathogen Xanthomonas hortorum pv. vitians and its host, lettuce (Lactuca sativa), remains completely unknown. To decipher the genes and functions mobilized by the pathogen throughout the infection process, we conducted a Tn-seq experiment in lettuce leaves to mimic the selective pressure occurring during natural infection. This genome-wide screening identified 170 genes whose disruption caused serious fitness defects in lettuce. A thorough examination of these genes using comparative genomics and gene set enrichment analyses highlighted that several functions and pathways were highly critical for the pathogen's survival. Numerous genes involved in amino acid, nucleic acid, and exopolysaccharide biosynthesis were critical. The xps type II secretion system operon, a few TonB-dependent transporters involved in carbohydrate or siderophore scavenging, and multiple genes of the carbohydrate catabolism pathways were also critical, emphasizing the importance of nutrition systems in a nutrient-limited environment. Finally, several genes implied in camouflage from the plant immune system and resistance to immunity-induced oxidative stress were strongly involved in host colonization. As a whole, these results highlight some of the central metabolic pathways and cellular functions critical for Xanthomonas host adaptation and pathogenesis. IMPORTANCE Xanthomonas hortorum was recently the subject of renewed interest, as several studies highlighted that its members were responsible for diseases in a wide range of plant species, including crops of agricultural relevance (e.g., tomato and carrot). Among X. hortorum variants, X. hortorum pv. vitians is a reemerging foliar hemibiotrophic phytopathogen responsible for severe outbreaks of bacterial leaf spot of lettuce all around the world. Despite recent findings, sustainable and practical means of disease control remain to be developed. Understanding the host-pathogen interaction from a molecular perspective is crucial to support these efforts. The genes and functions mobilized by X. hortorum pv. vitians during its interaction with lettuce had never been investigated. Our study sheds light on these processes by screening the whole pathogen genome for genes critical for its fitness during the infection process, using transposon insertion sequencing and comparative genomics.
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Affiliation(s)
- Lucas Morinière
- Université Lyon, Université Claude Bernard Lyon 1, CNRS, INRAE, VetAgro Sup, UMR Ecologie Microbienne, Villeurbanne, France
| | - Laurène Mirabel
- Université Lyon, Université Claude Bernard Lyon 1, CNRS, INRAE, VetAgro Sup, UMR Ecologie Microbienne, Villeurbanne, France
| | - Erwan Gueguen
- Université Lyon, Université Claude Bernard Lyon 1, INSA, CNRS, UMR Microbiologie, Adaptation, Pathogénie, Villeurbanne, France
| | - Franck Bertolla
- Université Lyon, Université Claude Bernard Lyon 1, CNRS, INRAE, VetAgro Sup, UMR Ecologie Microbienne, Villeurbanne, France
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8
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Duan S, Long Y, Cheng S, Li J, Ouyang Z, Wang N. Rapid Evaluation of the Resistance of Citrus Germplasms Against Xanthomonas citri subsp. citri. PHYTOPATHOLOGY 2022; 112:765-774. [PMID: 34495678 DOI: 10.1094/phyto-04-21-0175-r] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
Xanthomonas citri subsp. citri (Xcc) is the causal agent of citrus bacterial canker (CBC), one of the most devastating citrus diseases. Most commercial citrus varieties are susceptible to CBC. However, some citrus varieties and wild citrus germplasms are CBC resistant and are promising in genetic increases in citrus resistance against CBC. We aimed to evaluate citrus germplasms for resistance against CBC. First, we developed a rapid evaluation method based on enhanced yellow fluorescent protein (eYFP)-labeled Xcc. The results demonstrated that eYFP does not affect the growth and virulence of Xcc. Xcc-eYFP allows measurement of bacterial titers but is more efficient and rapid than the plate colony counting method. Next, we evaluated citrus germplasms collected in China. Based on symptoms and bacterial titers, we identified that two citrus germplasms ('Ichang' papeda and 'Huapi' kumquat) are resistant, whereas eight citrus germplasms ('Chongyi' wild mandarin, 'Mangshan' wild mandarin, 'Ledong' kumquat, 'Dali' citron, 'Yiliang' citron, 'Longyan' kumquat, 'Bawang' kumquat, and 'Daoxian' wild mandarin) are tolerant. In summary, we have developed a rapid evaluation method to test the resistance of citrus plants against CBC. This method was successfully used to identify two highly canker-resistant citrus germplasms and eight citrus germplasms with canker tolerance. These results could be leveraged in traditional breeding contexts or be used to identify canker resistance genes to increase the disease resistance of commercial citrus varieties via biotechnological approaches.
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Affiliation(s)
- Shuo Duan
- Citrus Huanglongbing Joint Laboratory, National Navel Orange Engineering Research Center, Gannan Normal University, Ganzhou, Jiangxi 341000, China
| | - Yunfei Long
- Citrus Huanglongbing Joint Laboratory, National Navel Orange Engineering Research Center, Gannan Normal University, Ganzhou, Jiangxi 341000, China
| | - Shuyuan Cheng
- Citrus Huanglongbing Joint Laboratory, National Navel Orange Engineering Research Center, Gannan Normal University, Ganzhou, Jiangxi 341000, China
| | - Jinyun Li
- Citrus Research and Education Center, Department of Microbiology and Cell Science, University of Florida, Lake Alfred, FL 33850, U.S.A
| | - Zhigang Ouyang
- Citrus Huanglongbing Joint Laboratory, National Navel Orange Engineering Research Center, Gannan Normal University, Ganzhou, Jiangxi 341000, China
| | - Nian Wang
- Citrus Research and Education Center, Department of Microbiology and Cell Science, University of Florida, Lake Alfred, FL 33850, U.S.A
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Lv X, Xu J, Sun C, Su F, Cai Y, Jin Z, Chi YR. Access to Planar Chiral Ferrocenes via N-Heterocyclic Carbene-Catalyzed Enantioselective Desymmetrization Reactions. ACS Catal 2022. [DOI: 10.1021/acscatal.2c00001] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Affiliation(s)
- Xiaokang Lv
- State Key Laboratory Breeding Base of Green Pesticide and Agricultural Bioengineering, Key Laboratory of Green Pesticide and Agricultural Bioengineering, Ministry of Education, Guizhou University, Huaxi District, Guiyang 550025, China
| | - Jun Xu
- School of Pharmacy, Guizhou University of Traditional Chinese Medicine, Huaxi District, Guiyang 550025, China
| | - Cuiyun Sun
- State Key Laboratory Breeding Base of Green Pesticide and Agricultural Bioengineering, Key Laboratory of Green Pesticide and Agricultural Bioengineering, Ministry of Education, Guizhou University, Huaxi District, Guiyang 550025, China
| | - Fen Su
- State Key Laboratory Breeding Base of Green Pesticide and Agricultural Bioengineering, Key Laboratory of Green Pesticide and Agricultural Bioengineering, Ministry of Education, Guizhou University, Huaxi District, Guiyang 550025, China
| | - Yuanlin Cai
- State Key Laboratory Breeding Base of Green Pesticide and Agricultural Bioengineering, Key Laboratory of Green Pesticide and Agricultural Bioengineering, Ministry of Education, Guizhou University, Huaxi District, Guiyang 550025, China
| | - Zhichao Jin
- State Key Laboratory Breeding Base of Green Pesticide and Agricultural Bioengineering, Key Laboratory of Green Pesticide and Agricultural Bioengineering, Ministry of Education, Guizhou University, Huaxi District, Guiyang 550025, China
| | - Yonggui Robin Chi
- State Key Laboratory Breeding Base of Green Pesticide and Agricultural Bioengineering, Key Laboratory of Green Pesticide and Agricultural Bioengineering, Ministry of Education, Guizhou University, Huaxi District, Guiyang 550025, China
- Division of Chemistry & Biological Chemistry, School of Physical & Mathematical Sciences, Nanyang Technological University, Singapore 637371, Singapore
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10
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Nakayinga R, Makumi A, Tumuhaise V, Tinzaara W. Xanthomonas bacteriophages: a review of their biology and biocontrol applications in agriculture. BMC Microbiol 2021; 21:291. [PMID: 34696726 PMCID: PMC8543423 DOI: 10.1186/s12866-021-02351-7] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2021] [Accepted: 10/12/2021] [Indexed: 11/10/2022] Open
Abstract
Phytopathogenic bacteria are economically important because they affect crop yields and threaten the livelihoods of farmers worldwide. The genus Xanthomonas is particularly significant because it is associated with some plant diseases that cause tremendous loss in yields of globally essential crops. Current management practices are ineffective, unsustainable and harmful to natural ecosystems. Bacteriophage (phage) biocontrol for plant disease management has been of particular interest from the early nineteenth century to date. Xanthomonas phage research for plant disease management continues to demonstrate promising results under laboratory and field conditions. AgriPhage has developed phage products for the control of Xanthomonas campestris pv. vesicatoria and Xanthomonas citri subsp. citri. These are causative agents for tomato, pepper spot and speck disease as well as citrus canker disease. Phage-mediated biocontrol is becoming a viable option because phages occur naturally and are safe for disease control and management. Thorough knowledge of biological characteristics of Xanthomonas phages is vital for developing effective biocontrol products. This review covers Xanthomonas phage research highlighting aspects of their ecology, biology and biocontrol applications.
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Affiliation(s)
- Ritah Nakayinga
- Department of Biological Sciences, Faculty of Science, Kyambogo University, P.O. Box 1, Kyambogo, Uganda.
| | - Angela Makumi
- Department of Animal and Human Health, General Biosciences, International Livestock Research Institute, P.O. Box 3070, Nairobi, 00100, Kenya
| | - Venansio Tumuhaise
- Department of Agriculture, Faculty of Vocational Studies, Kyambogo University, P.O. Box 1, Kyambogo, Uganda
| | - William Tinzaara
- Department of Agriculture, Faculty of Vocational Studies, Kyambogo University, P.O. Box 1, Kyambogo, Uganda
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11
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Di Lorenzo F, Duda KA, Lanzetta R, Silipo A, De Castro C, Molinaro A. A Journey from Structure to Function of Bacterial Lipopolysaccharides. Chem Rev 2021; 122:15767-15821. [PMID: 34286971 DOI: 10.1021/acs.chemrev.0c01321] [Citation(s) in RCA: 78] [Impact Index Per Article: 26.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
Lipopolysaccharide (LPS) is a crucial constituent of the outer membrane of most Gram-negative bacteria, playing a fundamental role in the protection of bacteria from environmental stress factors, in drug resistance, in pathogenesis, and in symbiosis. During the last decades, LPS has been thoroughly dissected, and massive information on this fascinating biomolecule is now available. In this Review, we will give the reader a third millennium update of the current knowledge of LPS with key information on the inherent peculiar carbohydrate chemistry due to often puzzling sugar residues that are uniquely found on it. Then, we will drive the reader through the complex and multifarious immunological outcomes that any given LPS can raise, which is strictly dependent on its chemical structure. Further, we will argue about issues that still remain unresolved and that would represent the immediate future of LPS research. It is critical to address these points to complete our notions on LPS chemistry, functions, and roles, in turn leading to innovative ways to manipulate the processes involving such a still controversial and intriguing biomolecule.
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Affiliation(s)
- Flaviana Di Lorenzo
- Department of Chemical Sciences, University of Naples Federico II, Via Cinthia 4, 80126 Naples, Italy.,Task Force on Microbiome Studies, University of Naples Federico II, Via Cinthia 4, 80126 Naples, Italy
| | - Katarzyna A Duda
- Research Center Borstel Leibniz Lung Center, Parkallee 4a, 23845 Borstel, Germany
| | - Rosa Lanzetta
- Department of Chemical Sciences, University of Naples Federico II, Via Cinthia 4, 80126 Naples, Italy
| | - Alba Silipo
- Department of Chemical Sciences, University of Naples Federico II, Via Cinthia 4, 80126 Naples, Italy.,Task Force on Microbiome Studies, University of Naples Federico II, Via Cinthia 4, 80126 Naples, Italy
| | - Cristina De Castro
- Task Force on Microbiome Studies, University of Naples Federico II, Via Cinthia 4, 80126 Naples, Italy.,Department of Agricultural Sciences, University of Naples Federico II, Via Università 96, 80055 Portici, Naples, Italy
| | - Antonio Molinaro
- Department of Chemical Sciences, University of Naples Federico II, Via Cinthia 4, 80126 Naples, Italy.,Task Force on Microbiome Studies, University of Naples Federico II, Via Cinthia 4, 80126 Naples, Italy.,Department of Chemistry, School of Science, Osaka University, 1-1 Osaka University Machikaneyama, Toyonaka, Osaka 560-0043, Japan
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12
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Tano J, Ripa MB, Tondo ML, Carrau A, Petrocelli S, Rodriguez MV, Ferreira V, Siri MI, Piskulic L, Orellano EG. Light modulates important physiological features of Ralstonia pseudosolanacearum during the colonization of tomato plants. Sci Rep 2021; 11:14531. [PMID: 34267245 PMCID: PMC8282871 DOI: 10.1038/s41598-021-93871-9] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2020] [Accepted: 06/25/2021] [Indexed: 02/06/2023] Open
Abstract
Ralstonia pseudosolanacearum GMI1000 (Rpso GMI1000) is a soil-borne vascular phytopathogen that infects host plants through the root system causing wilting disease in a wide range of agro-economic interest crops, producing economical losses. Several features contribute to the full bacterial virulence. In this work we study the participation of light, an important environmental factor, in the regulation of the physiological attributes and infectivity of Rpso GMI1000. In silico analysis of the Rpso genome revealed the presence of a Rsp0254 gene, which encodes a putative blue light LOV-type photoreceptor. We constructed a mutant strain of Rpso lacking the LOV protein and found that the loss of this protein and light, influenced characteristics involved in the pathogenicity process such as motility, adhesion and the biofilms development, which allows the successful host plant colonization, rendering bacterial wilt. This protein could be involved in the adaptive responses to environmental changes. We demonstrated that light sensing and the LOV protein, would be used as a location signal in the host plant, to regulate the expression of several virulence factors, in a time and tissue dependent way. Consequently, bacteria could use an external signal and Rpsolov gene to know their location within plant tissue during the colonization process.
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Affiliation(s)
- Josefina Tano
- Instituto de Biología Molecular y Celular de Rosario, Facultad de Ciencias Bioquímicas y Farmacéuticas (IBR-FBIOyF), Consejo Nacional de Investigaciones Científicas y Técnicas, Universidad Nacional de Rosario (CONICET-UNR), Suipacha 531, S2002LRK, Rosario, Argentina
| | - María Belén Ripa
- Instituto de Biología Molecular y Celular de Rosario, Facultad de Ciencias Bioquímicas y Farmacéuticas (IBR-FBIOyF), Consejo Nacional de Investigaciones Científicas y Técnicas, Universidad Nacional de Rosario (CONICET-UNR), Suipacha 531, S2002LRK, Rosario, Argentina
| | - María Laura Tondo
- Facultad de Ciencias Bioquímicas y Farmacéuticas, Universidad Nacional de Rosario, Rosario, Argentina
| | - Analía Carrau
- Instituto de Biología Molecular y Celular de Rosario, Facultad de Ciencias Bioquímicas y Farmacéuticas (IBR-FBIOyF), Consejo Nacional de Investigaciones Científicas y Técnicas, Universidad Nacional de Rosario (CONICET-UNR), Suipacha 531, S2002LRK, Rosario, Argentina
| | - Silvana Petrocelli
- Facultad de Ciencias Bioquímicas y Farmacéuticas, Universidad Nacional de Rosario, Rosario, Argentina
| | - María Victoria Rodriguez
- Área Biología Vegetal, Facultad de Ciencias Bioquímicas y Farmacéuticas, Universidad Nacional de Rosario, Rosario, Argentina
| | - Virginia Ferreira
- Área Microbiología, Departamento de Biociencias, Facultad de Química, Universidad de la República, Montevideo, Uruguay
| | - María Inés Siri
- Área Microbiología, Departamento de Biociencias, Facultad de Química, Universidad de la República, Montevideo, Uruguay
| | - Laura Piskulic
- Área Estadística y Procesamiento de datos, Facultad de Ciencias Bioquímicas y Farmacéuticas, Universidad Nacional de Rosario, Rosario, Argentina
| | - Elena Graciela Orellano
- Instituto de Biología Molecular y Celular de Rosario, Facultad de Ciencias Bioquímicas y Farmacéuticas (IBR-FBIOyF), Consejo Nacional de Investigaciones Científicas y Técnicas, Universidad Nacional de Rosario (CONICET-UNR), Suipacha 531, S2002LRK, Rosario, Argentina.
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13
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Bacteriophage-Mediated Control of Phytopathogenic Xanthomonads: A Promising Green Solution for the Future. Microorganisms 2021; 9:microorganisms9051056. [PMID: 34068401 PMCID: PMC8153558 DOI: 10.3390/microorganisms9051056] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2021] [Revised: 05/05/2021] [Accepted: 05/11/2021] [Indexed: 12/21/2022] Open
Abstract
Xanthomonads, members of the family Xanthomonadaceae, are economically important plant pathogenic bacteria responsible for infections of over 400 plant species. Bacteriophage-based biopesticides can provide an environmentally friendly, effective solution to control these bacteria. Bacteriophage-based biocontrol has important advantages over chemical pesticides, and treatment with these biopesticides is a minor intervention into the microflora. However, bacteriophages’ agricultural application has limitations rooted in these viruses’ biological properties as active substances. These disadvantageous features, together with the complicated registration process of bacteriophage-based biopesticides, means that there are few products available on the market. This review summarizes our knowledge of the Xanthomonas-host plant and bacteriophage-host bacterium interaction’s possible influence on bacteriophage-based biocontrol strategies and provides examples of greenhouse and field trials and products readily available in the EU and the USA. It also details the most important advantages and limitations of the agricultural application of bacteriophages. This paper also investigates the legal background and industrial property right issues of bacteriophage-based biopesticides. When appropriately applied, bacteriophages can provide a promising tool against xanthomonads, a possibility that is untapped. Information presented in this review aims to explore the potential of bacteriophage-based biopesticides in the control of xanthomonads in the future.
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14
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An SQ, Potnis N, Dow M, Vorhölter FJ, He YQ, Becker A, Teper D, Li Y, Wang N, Bleris L, Tang JL. Mechanistic insights into host adaptation, virulence and epidemiology of the phytopathogen Xanthomonas. FEMS Microbiol Rev 2020; 44:1-32. [PMID: 31578554 PMCID: PMC8042644 DOI: 10.1093/femsre/fuz024] [Citation(s) in RCA: 117] [Impact Index Per Article: 29.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2019] [Accepted: 09/29/2019] [Indexed: 01/15/2023] Open
Abstract
Xanthomonas is a well-studied genus of bacterial plant pathogens whose members cause a variety of diseases in economically important crops worldwide. Genomic and functional studies of these phytopathogens have provided significant understanding of microbial-host interactions, bacterial virulence and host adaptation mechanisms including microbial ecology and epidemiology. In addition, several strains of Xanthomonas are important as producers of the extracellular polysaccharide, xanthan, used in the food and pharmaceutical industries. This polymer has also been implicated in several phases of the bacterial disease cycle. In this review, we summarise the current knowledge on the infection strategies and regulatory networks controlling virulence and adaptation mechanisms from Xanthomonas species and discuss the novel opportunities that this body of work has provided for disease control and plant health.
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Affiliation(s)
- Shi-Qi An
- National Biofilms Innovation Centre (NBIC), Biological Sciences, University of Southampton, University Road, Southampton SO17 1BJ, UK
| | - Neha Potnis
- Department of Entomology and Plant Pathology, Rouse Life Science Building, Auburn University, Auburn AL36849, USA
| | - Max Dow
- School of Microbiology, Food Science & Technology Building, University College Cork, Cork T12 K8AF, Ireland
| | | | - Yong-Qiang He
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-bioresources, College of Life Science and Technology, Guangxi University, 100 Daxue Road, Nanning 530004, Guangxi, China
| | - Anke Becker
- Loewe Center for Synthetic Microbiology and Department of Biology, Philipps-Universität Marburg, Hans-Meerwein-Straße 6, Marburg 35032, Germany
| | - Doron Teper
- Citrus Research and Education Center, Department of Microbiology and Cell Science, Institute of Food and Agricultural Sciences, University of Florida, 700 Experiment Station Road, Lake Alfred 33850, USA
| | - Yi Li
- Bioengineering Department, University of Texas at Dallas, 2851 Rutford Ave, Richardson, TX 75080, USA.,Center for Systems Biology, University of Texas at Dallas, 800 W Campbell Road, Richardson, TX 75080, USA
| | - Nian Wang
- Citrus Research and Education Center, Department of Microbiology and Cell Science, Institute of Food and Agricultural Sciences, University of Florida, 700 Experiment Station Road, Lake Alfred 33850, USA
| | - Leonidas Bleris
- Bioengineering Department, University of Texas at Dallas, 2851 Rutford Ave, Richardson, TX 75080, USA.,Center for Systems Biology, University of Texas at Dallas, 800 W Campbell Road, Richardson, TX 75080, USA.,Department of Biological Sciences, University of Texas at Dallas, 800 W Campbell Road, Richardson, TX75080, USA
| | - Ji-Liang Tang
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-bioresources, College of Life Science and Technology, Guangxi University, 100 Daxue Road, Nanning 530004, Guangxi, China
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15
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Pena MM, Teper D, Ferreira H, Wang N, Sato KU, Ferro MIT, Ferro JA. mCherry fusions enable the subcellular localization of periplasmic and cytoplasmic proteins in Xanthomonas sp. PLoS One 2020; 15:e0236185. [PMID: 32730344 PMCID: PMC7392301 DOI: 10.1371/journal.pone.0236185] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2020] [Accepted: 06/30/2020] [Indexed: 12/18/2022] Open
Abstract
Fluorescent markers are a powerful tool and have been widely applied in biology for different purposes. The genome sequence of Xanthomonas citri subsp. citri (X. citri) revealed that approximately 30% of the genes encoded hypothetical proteins, some of which could play an important role in the success of plant-pathogen interaction and disease triggering. Therefore, revealing their functions is an important strategy to understand the bacterium pathways and mechanisms involved in plant-host interaction. The elucidation of protein function is not a trivial task, but the identification of the subcellular localization of a protein is key to understanding its function. We have constructed an integrative vector, pMAJIIc, under the control of the arabinose promoter, which allows the inducible expression of red fluorescent protein (mCherry) fusions in X. citri, suitable for subcellular localization of target proteins. Fluorescence microscopy was used to track the localization of VrpA protein, which was visualized surrounding the bacterial outer membrane, and the GyrB protein, which showed a diffused cytoplasmic localization, sometimes with dots accumulated near the cellular poles. The integration of the vector into the amy locus of X. citri did not affect bacterial virulence. The vector could be stably maintained in X. citri, and the disruption of the α-amylase gene provided an ease screening method for the selection of the transformant colonies. The results demonstrate that the mCherry-containing vector here described is a powerful tool for bacterial protein localization in cytoplasmic and periplasmic environments.
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Affiliation(s)
- Michelle Mendonça Pena
- Agricultural and Livestock Microbiology Graduation Program, School of Agricultural and Veterinarian Sciences, São Paulo State University (UNESP), Jaboticabal, SP, Brazil
| | - Doron Teper
- Department of Microbiology and Cell Science, Citrus Research and Education Center, University of Florida, Lake Alfred, FL, United States of America
| | - Henrique Ferreira
- Department of Biochemistry and Microbiology, Biosciences Institute, São Paulo State University (UNESP), Rio Claro, SP, Brazil
| | - Nian Wang
- Department of Microbiology and Cell Science, Citrus Research and Education Center, University of Florida, Lake Alfred, FL, United States of America
| | - Kenny Umino Sato
- Department of Biochemistry and Microbiology, Biosciences Institute, São Paulo State University (UNESP), Rio Claro, SP, Brazil
| | - Maria Inês Tiraboschi Ferro
- Department of Technology, School of Agricultural and Veterinarian Sciences, São Paulo State University (UNESP), Jaboticabal, SP, Brazil
| | - Jesus Aparecido Ferro
- Department of Technology, School of Agricultural and Veterinarian Sciences, São Paulo State University (UNESP), Jaboticabal, SP, Brazil
- * E-mail:
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16
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Costa-Gutierrez SB, Lami MJ, Santo MCCD, Zenoff AM, Vincent PA, Molina-Henares MA, Espinosa-Urgel M, de Cristóbal RE. Plant growth promotion by Pseudomonas putida KT2440 under saline stress: role of eptA. Appl Microbiol Biotechnol 2020; 104:4577-4592. [PMID: 32221691 DOI: 10.1007/s00253-020-10516-z] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2019] [Revised: 02/11/2020] [Accepted: 03/01/2020] [Indexed: 01/22/2023]
Abstract
New strategies to improve crop yield include the incorporation of plant growth-promoting bacteria in agricultural practices. The non-pathogenic bacterium Pseudomonas putida KT2440 is an excellent root colonizer of crops of agronomical importance and has been shown to activate the induced systemic resistance of plants in response to certain foliar pathogens. In this work, we have analyzed additional plant growth promotion features of this strain. We show it can tolerate high NaCl concentrations and determine how salinity influences traits such as the production of indole compounds, siderophore synthesis, and phosphate solubilization. Inoculation with P. putida KT2440 significantly improved seed germination and root and stem length of soybean and corn plants under saline conditions compared to uninoculated plants, whereas the effects were minor under non-saline conditions. Also, random transposon mutagenesis was used for preliminary identification of KT2440 genes involved in bacterial tolerance to saline stress. One of the obtained mutants was analyzed in detail. The disrupted gene encodes a predicted phosphoethanolamine-lipid A transferase (EptA), an enzyme described to be involved in the modification of lipid A during lipopolysaccharide (LPS) biosynthesis. This mutant showed changes in exopolysaccharide (EPS) production, low salinity tolerance, and reduced competitive fitness in the rhizosphere.
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Affiliation(s)
- Stefanie B Costa-Gutierrez
- Instituto Superior de Investigaciones Biológicas (INSIBIO, CONICET-UNT) and Instituto de Química Biológica "Dr. Bernabé Bloj", Facultad de Bioquímica, Química y Farmacia, Universidad Nacional de Tucumán, Chacabuco 461, T4000ILI, San Miguel de Tucumán, Tucumán, Argentina
| | - María Jesús Lami
- Instituto Superior de Investigaciones Biológicas (INSIBIO, CONICET-UNT) and Instituto de Química Biológica "Dr. Bernabé Bloj", Facultad de Bioquímica, Química y Farmacia, Universidad Nacional de Tucumán, Chacabuco 461, T4000ILI, San Miguel de Tucumán, Tucumán, Argentina
| | - María Carolina Caram-Di Santo
- Instituto Superior de Investigaciones Biológicas (INSIBIO, CONICET-UNT) and Instituto de Química Biológica "Dr. Bernabé Bloj", Facultad de Bioquímica, Química y Farmacia, Universidad Nacional de Tucumán, Chacabuco 461, T4000ILI, San Miguel de Tucumán, Tucumán, Argentina
| | - Ana M Zenoff
- Instituto Superior de Investigaciones Biológicas (INSIBIO, CONICET-UNT) and Instituto de Química Biológica "Dr. Bernabé Bloj", Facultad de Bioquímica, Química y Farmacia, Universidad Nacional de Tucumán, Chacabuco 461, T4000ILI, San Miguel de Tucumán, Tucumán, Argentina
| | - Paula A Vincent
- Instituto Superior de Investigaciones Biológicas (INSIBIO, CONICET-UNT) and Instituto de Química Biológica "Dr. Bernabé Bloj", Facultad de Bioquímica, Química y Farmacia, Universidad Nacional de Tucumán, Chacabuco 461, T4000ILI, San Miguel de Tucumán, Tucumán, Argentina
| | | | - Manuel Espinosa-Urgel
- Department of Environmental Protection, Estación Experimental del Zaidín, CSIC, Granada, Spain
| | - Ricardo E de Cristóbal
- Instituto Superior de Investigaciones Biológicas (INSIBIO, CONICET-UNT) and Instituto de Química Biológica "Dr. Bernabé Bloj", Facultad de Bioquímica, Química y Farmacia, Universidad Nacional de Tucumán, Chacabuco 461, T4000ILI, San Miguel de Tucumán, Tucumán, Argentina.
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17
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Thapa SP, De Francesco A, Trinh J, Gurung FB, Pang Z, Vidalakis G, Wang N, Ancona V, Ma W, Coaker G. Genome-wide analyses of Liberibacter species provides insights into evolution, phylogenetic relationships, and virulence factors. MOLECULAR PLANT PATHOLOGY 2020; 21:716-731. [PMID: 32108417 PMCID: PMC7170780 DOI: 10.1111/mpp.12925] [Citation(s) in RCA: 48] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/08/2019] [Revised: 01/27/2020] [Accepted: 01/28/2020] [Indexed: 05/04/2023]
Abstract
'Candidatus Liberibacter' species are insect-transmitted, phloem-limited α-Proteobacteria in the order of Rhizobiales. The citrus industry is facing significant challenges due to huanglongbing, associated with infection from 'Candidatus Liberibacter asiaticus' (Las). In order to gain greater insight into 'Ca. Liberibacter' biology and genetic diversity, we have performed genome sequencing and comparative analyses of diverse 'Ca. Liberibacter' species, including those that can infect citrus. Our phylogenetic analysis differentiates 'Ca. Liberibacter' species and Rhizobiales in separate clades and suggests stepwise evolution from a common ancestor splitting first into nonpathogenic Liberibacter crescens followed by diversification of pathogenic 'Ca. Liberibacter' species. Further analysis of Las genomes from different geographical locations revealed diversity among isolates from the United States. Our phylogenetic study also indicates multiple Las introduction events in California and spread of the pathogen from Florida to Texas. Texan Las isolates were closely related, while Florida and Asian isolates exhibited the most genetic variation. We have identified conserved Sec translocon (SEC)-dependent effectors likely involved in bacterial survival and virulence of Las and analysed their expression in their plant host (citrus) and insect vector (Diaphorina citri). Individual SEC-dependent effectors exhibited differential expression patterns between host and vector, indicating that Las uses its effector repertoire to differentially modulate diverse organisms. Collectively, this work provides insights into the evolution of 'Ca. Liberibacter' species, the introduction of Las in the United States and identifies promising Las targets for disease management.
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Affiliation(s)
- Shree P. Thapa
- Department of Plant PathologyUniversity of CaliforniaDavisCAUSA
| | - Agustina De Francesco
- Department of Microbiology and Plant PathologyUniversity of CaliforniaRiversideCAUSA
| | - Jessica Trinh
- Department of Microbiology and Plant PathologyUniversity of CaliforniaRiversideCAUSA
| | - Fatta B. Gurung
- Citrus CenterDepartment of Agriculture, Agribusiness and Environmental SciencesTexas A&M University‐KingsvilleWeslacoTXUSA
| | - Zhiqian Pang
- Citrus Research and Education CenterDepartment of Microbiology and Cell ScienceUniversity of FloridaLake AlfredFLUSA
| | - Georgios Vidalakis
- Department of Microbiology and Plant PathologyUniversity of CaliforniaRiversideCAUSA
| | - Nian Wang
- Citrus Research and Education CenterDepartment of Microbiology and Cell ScienceUniversity of FloridaLake AlfredFLUSA
| | - Veronica Ancona
- Citrus CenterDepartment of Agriculture, Agribusiness and Environmental SciencesTexas A&M University‐KingsvilleWeslacoTXUSA
| | - Wenbo Ma
- Department of Microbiology and Plant PathologyUniversity of CaliforniaRiversideCAUSA
| | - Gitta Coaker
- Department of Plant PathologyUniversity of CaliforniaDavisCAUSA
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18
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Kutschera A, Schombel U, Wröbel M, Gisch N, Ranf S. Loss of wbpL disrupts O-polysaccharide synthesis and impairs virulence of plant-associated Pseudomonas strains. MOLECULAR PLANT PATHOLOGY 2019; 20:1535-1549. [PMID: 31559681 PMCID: PMC6804347 DOI: 10.1111/mpp.12864] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/16/2023]
Abstract
Despite its importance for membrane stability and pathogenicity of mammalian pathogens, functions of the O-polysaccharide (OPS) of lipopolysaccharide (LPS) remain unclear in plant-associated bacteria. Genetic information about OPS biosynthesis in these bacteria is largely missing. Genome analysis of various plant-associated Pseudomonas strains revealed that one of the two known OPS biosynthesis clusters from Pseudomonas aeruginosa PAO1, the common polysaccharide antigen (CPA) gene cluster, is only conserved in some strains of the Pseudomonas fluorescens group. For the O-specific antigen (OSA) biosynthesis cluster, the putative genomic position could be identified, but orthologues of most functional important OSA biosynthesis enzymes could not be detected. Nevertheless, orthologues of the glycosyltransferase WbpL, required for initiation of CPA and OSA synthesis in P. aeruginosa PAO1, could be identified in the analysed Pseudomonas genomes. Knockout mutations of wbpL orthologues in Pseudomonas syringae pv. tomato DC3000 (Pst) and Pseudomonas cichorii ATCC10857/DSM50259 (Pci) resulted in strains lacking the OPS. Infection experiments of Arabidopsis thaliana plants revealed a reduced entry into the leaf apoplast after spray inoculation and a reduced apoplastic amplification of Pst ∆wbpL. Stab and spray inoculation of lettuce (Lactuca sativa) leaves with Pci ∆wbpL causes reduced infection symptoms compared to the wild-type strain. Furthermore, swarming motility was reduced in ∆wbpL mutants of Pst and Pci. This might be a possible reason for reduced bacterial titres after surface inoculation and reduced bacterial amplification in the plant. Our results imply that the presence of lipopolysaccharide OPS is required for efficient host colonization and full virulence of plant-pathogenic Pseudomonas bacteria.
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Affiliation(s)
- Alexander Kutschera
- Technical University of MunichPhytopathology, TUM School of Life Sciences Weihenstephan85354Freising‐WeihenstephanGermany
| | - Ursula Schombel
- Research Center Borstel, Leibniz Lung CenterDivision of Bioanalytical Chemistry, Priority Area InfectionsParkallee 1‐4023845BorstelGermany
| | - Michelle Wröbel
- Research Center Borstel, Leibniz Lung CenterDivision of Bioanalytical Chemistry, Priority Area InfectionsParkallee 1‐4023845BorstelGermany
| | - Nicolas Gisch
- Research Center Borstel, Leibniz Lung CenterDivision of Bioanalytical Chemistry, Priority Area InfectionsParkallee 1‐4023845BorstelGermany
| | - Stefanie Ranf
- Technical University of MunichPhytopathology, TUM School of Life Sciences Weihenstephan85354Freising‐WeihenstephanGermany
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Barcarolo MV, Garavaglia BS, Thomas L, Marondedze C, Gehring C, Gottig N, Ottado J. Proteome changes and physiological adaptations of the phytopathogen Xanthomonas citri subsp. citri under salt stress and their implications for virulence. FEMS Microbiol Ecol 2019; 95:5509571. [DOI: 10.1093/femsec/fiz081] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2019] [Accepted: 05/30/2019] [Indexed: 12/17/2022] Open
Affiliation(s)
- María Victoria Barcarolo
- Instituto de Biología Molecular y Celular de Rosario, Consejo Nacional de Investigaciones Científicas y Técnicas (IBR-CONICET) and Facultad de Ciencias Bioquímicas y Farmacéuticas, Universidad Nacional de Rosario (UNR). Ocampo y Esmeralda, Rosario, 2000, Argentina
| | - Betiana S Garavaglia
- Instituto de Biología Molecular y Celular de Rosario, Consejo Nacional de Investigaciones Científicas y Técnicas (IBR-CONICET) and Facultad de Ciencias Bioquímicas y Farmacéuticas, Universidad Nacional de Rosario (UNR). Ocampo y Esmeralda, Rosario, 2000, Argentina
| | - Ludivine Thomas
- HM.Clause, rue Louis Saillant, 26801 Portes-lès-Valence, France
| | - Claudius Marondedze
- Laboratoire de Physiologie Cellulaire et Végétale, Université Grenoble Alpes, CEA/DRF/BIG, INRA UMR1417, CNRS UMR5168, 38054 Grenoble Cedex 9, France
| | - Chris Gehring
- Department of Chemistry, Biology & Biotechnology, University of Perugia,
06121 Perugia, Italy
| | - Natalia Gottig
- Instituto de Biología Molecular y Celular de Rosario, Consejo Nacional de Investigaciones Científicas y Técnicas (IBR-CONICET) and Facultad de Ciencias Bioquímicas y Farmacéuticas, Universidad Nacional de Rosario (UNR). Ocampo y Esmeralda, Rosario, 2000, Argentina
| | - Jorgelina Ottado
- Instituto de Biología Molecular y Celular de Rosario, Consejo Nacional de Investigaciones Científicas y Técnicas (IBR-CONICET) and Facultad de Ciencias Bioquímicas y Farmacéuticas, Universidad Nacional de Rosario (UNR). Ocampo y Esmeralda, Rosario, 2000, Argentina
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20
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Héloir MC, Adrian M, Brulé D, Claverie J, Cordelier S, Daire X, Dorey S, Gauthier A, Lemaître-Guillier C, Negrel J, Trdá L, Trouvelot S, Vandelle E, Poinssot B. Recognition of Elicitors in Grapevine: From MAMP and DAMP Perception to Induced Resistance. FRONTIERS IN PLANT SCIENCE 2019; 10:1117. [PMID: 31620151 PMCID: PMC6760519 DOI: 10.3389/fpls.2019.01117] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/19/2019] [Accepted: 08/14/2019] [Indexed: 05/21/2023]
Abstract
In a context of a sustainable viticulture, the implementation of innovative eco-friendly strategies, such as elicitor-triggered immunity, requires a deep knowledge of the molecular mechanisms underlying grapevine defense activation, from pathogen perception to resistance induction. During plant-pathogen interaction, the first step of plant defense activation is ensured by the recognition of microbe-associated molecular patterns, which are elicitors directly derived from pathogenic or beneficial microbes. Vitis vinifera, like other plants, can perceive elicitors of different nature, including proteins, amphiphilic glycolipid, and lipopeptide molecules as well as polysaccharides, thanks to their cognate pattern recognition receptors, the discovery of which recently began in this plant species. Furthermore, damage-associated molecular patterns are another class of elicitors perceived by V. vinifera as an invader's hallmark. They are mainly polysaccharides derived from the plant cell wall and are generally released through the activity of cell wall-degrading enzymes secreted by microbes. Elicitor perception and subsequent activation of grapevine immunity end in some cases in efficient grapevine resistance against pathogens. Using complementary approaches, several molecular markers have been identified as hallmarks of this induced resistance stage. This review thus focuses on the recognition of elicitors by Vitis vinifera describing the molecular mechanisms triggered from the elicitor perception to the activation of immune responses. Finally, we discuss the fact that the link between elicitation and induced resistance is not so obvious and that the formulation of resistance inducers remains a key step before their application in vineyards.
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Affiliation(s)
- Marie-Claire Héloir
- Agroécologie, Agrosup Dijon, CNRS, INRA, Univ. Bourgogne, Univ. Bourgogne Franche-Comté, Dijon, France
| | - Marielle Adrian
- Agroécologie, Agrosup Dijon, CNRS, INRA, Univ. Bourgogne, Univ. Bourgogne Franche-Comté, Dijon, France
| | - Daphnée Brulé
- Agroécologie, Agrosup Dijon, CNRS, INRA, Univ. Bourgogne, Univ. Bourgogne Franche-Comté, Dijon, France
| | - Justine Claverie
- Agroécologie, Agrosup Dijon, CNRS, INRA, Univ. Bourgogne, Univ. Bourgogne Franche-Comté, Dijon, France
| | - Sylvain Cordelier
- Unité RIBP EA 4707, SFR Condorcet FR CNRS 3417, University of Reims Champagne-Ardenne, Reims, France
| | - Xavier Daire
- Agroécologie, Agrosup Dijon, CNRS, INRA, Univ. Bourgogne, Univ. Bourgogne Franche-Comté, Dijon, France
| | - Stéphan Dorey
- Unité RIBP EA 4707, SFR Condorcet FR CNRS 3417, University of Reims Champagne-Ardenne, Reims, France
| | - Adrien Gauthier
- Agroécologie, Agrosup Dijon, CNRS, INRA, Univ. Bourgogne, Univ. Bourgogne Franche-Comté, Dijon, France
- UniLaSalle, AGHYLE Research Unit UP 2018.C101, Rouen, France
| | | | - Jonathan Negrel
- Agroécologie, Agrosup Dijon, CNRS, INRA, Univ. Bourgogne, Univ. Bourgogne Franche-Comté, Dijon, France
| | - Lucie Trdá
- Agroécologie, Agrosup Dijon, CNRS, INRA, Univ. Bourgogne, Univ. Bourgogne Franche-Comté, Dijon, France
- Laboratory of Pathological Plant Physiology, Institute of Experimental Botany, the Czech Academy of Sciences, Prague, Czechia
| | - Sophie Trouvelot
- Agroécologie, Agrosup Dijon, CNRS, INRA, Univ. Bourgogne, Univ. Bourgogne Franche-Comté, Dijon, France
| | - Elodie Vandelle
- Agroécologie, Agrosup Dijon, CNRS, INRA, Univ. Bourgogne, Univ. Bourgogne Franche-Comté, Dijon, France
- Laboratory of Plant Pathology, Department of Biotechnology, University of Verona, Verona, Italy
| | - Benoit Poinssot
- Agroécologie, Agrosup Dijon, CNRS, INRA, Univ. Bourgogne, Univ. Bourgogne Franche-Comté, Dijon, France
- *Correspondence: Benoit Poinssot,
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21
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Sorroche F, Bogino P, Russo DM, Zorreguieta A, Nievas F, Morales GM, Hirsch AM, Giordano W. Cell Autoaggregation, Biofilm Formation, and Plant Attachment in a Sinorhizobium meliloti lpsB Mutant. MOLECULAR PLANT-MICROBE INTERACTIONS : MPMI 2018; 31:1075-1082. [PMID: 30136892 DOI: 10.1094/mpmi-01-18-0004-r] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
Bacterial surface molecules are crucial for the establishment of a successful rhizobia-legume symbiosis, and, in most bacteria, are also critical for adherence properties, surface colonization, and as a barrier for defense. Rhizobial mutants defective in the production of exopolysaccharides (EPSs), lipopolysaccharides (LPSs), or capsular polysaccharides are usually affected in symbiosis with their plant hosts. In the present study, we evaluated the role of the combined effects of LPS and EPS II in cell-to-cell and cell-to-surface interactions in Sinorhizobium meliloti by studying planktonic cell autoaggregation, biofilm formation, and symbiosis with the host plant Medicago sativa. The lpsB mutant, which has a defective core portion of LPS, exhibited a reduction in biofilm formation on abiotic surfaces as well as altered biofilm architecture compared with the wild-type Rm8530 strain. Atomic force microscopy and confocal laser microscopy revealed an increase in polar cell-to-cell interactions in the lpsB mutant, which might account for the biofilm deficiency. However, a certain level of biofilm development was observed in the lpsB strain compared with the EPS II-defective mutant strains. Autoaggregation experiments carried out with LPS and EPS mutant strains showed that both polysaccharides have an impact on the cell-to-cell adhesive interactions of planktonic bacteria. Although the lpsB mutation and the loss of EPS II production strongly stimulated early attachment to alfalfa roots, the number of nodules induced in M. sativa was not increased. Taken together, this work demonstrates that S. meliloti interactions with biotic and abiotic surfaces depend on the interplay between LPS and EPS II.
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Affiliation(s)
- Fernando Sorroche
- 1 Departamento de Biología Molecular, Universidad Nacional de Río Cuarto, Río Cuarto, Córdoba, Argentina
| | - Pablo Bogino
- 1 Departamento de Biología Molecular, Universidad Nacional de Río Cuarto, Río Cuarto, Córdoba, Argentina
| | - Daniela M Russo
- 2 Fundación Instituto Leloir and IIBBA CONICET, Buenos Aires, Argentina
| | | | - Fiorela Nievas
- 1 Departamento de Biología Molecular, Universidad Nacional de Río Cuarto, Río Cuarto, Córdoba, Argentina
| | - Gustavo M Morales
- 3 Departamento de Química, Universidad Nacional de Río Cuarto, Río Cuarto, Argentina; and
| | - Ann M Hirsch
- 4 Department of Molecular, Cell and Developmental Biology and Molecular Biology Institute, University of California-Los Angeles, U.S.A
| | - Walter Giordano
- 1 Departamento de Biología Molecular, Universidad Nacional de Río Cuarto, Río Cuarto, Córdoba, Argentina
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22
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Kutschera A, Ranf S. The multifaceted functions of lipopolysaccharide in plant-bacteria interactions. Biochimie 2018; 159:93-98. [PMID: 30077817 DOI: 10.1016/j.biochi.2018.07.028] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2018] [Accepted: 07/31/2018] [Indexed: 12/12/2022]
Abstract
In Gram-negative bacteria, the cell envelope largely consists of lipopolysaccharide (LPS), a class of heterogeneous glycolipids. As a fundamental component of the outer membrane, LPS provides stability to the bacterial cell and forms a protective cover shielding it from hostile environments. LPS is not only fundamental to bacterial viability, but also makes a substantial contribution both directly and indirectly to multiple aspects of inter-organismic interactions. During infection of animal and plant hosts, LPS promotes bacterial virulence but simultaneously betrays bacteria to the host immune system. Moreover, dynamic remodulation of LPS structures allows bacteria to fine-tune OM properties and quickly adapt to diverse and often hostile environments, such as those encountered in host tissues. Here, we summarize recent insights into the multiple functions of LPS in plant-bacteria interactions and discuss what we can learn from the latest advances in the field of animal immunity. We further pinpoint open questions and future challenges to unravel the different roles of LPS in the dynamic interplay between bacteria and plant hosts at the mechanistic level.
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Affiliation(s)
- Alexander Kutschera
- Chair of Phytopathology, TUM School of Life Sciences Weihenstephan, Technical University of Munich, 85354, Freising-Weihenstephan, Germany
| | - Stefanie Ranf
- Chair of Phytopathology, TUM School of Life Sciences Weihenstephan, Technical University of Munich, 85354, Freising-Weihenstephan, Germany.
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23
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Ference CM, Gochez AM, Behlau F, Wang N, Graham JH, Jones JB. Recent advances in the understanding of Xanthomonas citri ssp. citri pathogenesis and citrus canker disease management. MOLECULAR PLANT PATHOLOGY 2018; 19:1302-1318. [PMID: 29105297 PMCID: PMC6638175 DOI: 10.1111/mpp.12638] [Citation(s) in RCA: 70] [Impact Index Per Article: 11.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/20/2017] [Revised: 10/29/2017] [Accepted: 10/31/2017] [Indexed: 05/09/2023]
Abstract
Taxonomic status: Bacteria; Phylum Proteobacteria; Class Gammaproteobacteria; Order Xanthomonadales; Family Xanthomonadaceae; Genus Xanthomonas; Species Xanthomonas citri ssp. citri (Xcc). Host range: Compatible hosts vary in their susceptibility to citrus canker (CC), with grapefruit, lime and lemon being the most susceptible, sweet orange being moderately susceptible, and kumquat and calamondin being amongst the least susceptible. Microbiological properties: Xcc is a rod-shaped (1.5-2.0 × 0.5-0.75 µm), Gram-negative, aerobic bacterium with a single polar flagellum. The bacterium forms yellow colonies on culture media as a result of the production of xanthomonadin. Distribution: Present in South America, the British Virgin Islands, Africa, the Middle East, India, Asia and the South Pacific islands. Localized incidence in the USA, Argentina, Brazil, Bolivia, Uruguay, Senegal, Mali, Burkina Faso, Tanzania, Iran, Saudi Arabia, Yemen and Bangladesh. Widespread throughout Paraguay, Comoros, China, Japan, Malaysia and Vietnam. Eradicated from South Africa, Australia and New Zealand. Absent from Europe.
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Affiliation(s)
- Christopher M. Ference
- United States Department of Agriculture, Agricultural Research Service, US Horticultural Research LaboratoryFort PierceFL 34945USA
- Department of Plant PathologyUniversity of FloridaGainesvilleFL 32611USA
| | - Alberto M. Gochez
- Citrus Pathology, EEA INTA Bella VistaBella VistaCorrientes 3432Argentina
| | - Franklin Behlau
- Department of Research & DevelopmentFundo de Defesa da Citricultura (Fundecitrus)AraraquaraSão Paulo 14.807‐040Brazil
| | - Nian Wang
- Department of Microbiology and Cell Science, Citrus Research and Education Center, University of FloridaLake AlfredFL 33850USA
| | - James H. Graham
- Department of Soil and Water Science, Citrus Research and Education Center, University of FloridaLake AlfredFL 33850USA
| | - Jeffrey B. Jones
- Department of Plant PathologyUniversity of FloridaGainesvilleFL 32611USA
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24
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Artier J, da Silva Zandonadi F, de Souza Carvalho FM, Pauletti BA, Leme AFP, Carnielli CM, Selistre‐de‐Araujo HS, Bertolini MC, Ferro JA, Belasque Júnior J, de Oliveira JCF, Novo‐Mansur MTM. Comparative proteomic analysis of Xanthomonas citri ssp. citri periplasmic proteins reveals changes in cellular envelope metabolism during in vitro pathogenicity induction. MOLECULAR PLANT PATHOLOGY 2018; 19:143-157. [PMID: 27798950 PMCID: PMC6638008 DOI: 10.1111/mpp.12507] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
Citrus canker is a plant disease caused by Gram-negative bacteria from the genus Xanthomonas. The most virulent species is Xanthomonas citri ssp. citri (XAC), which attacks a wide range of citrus hosts. Differential proteomic analysis of the periplasm-enriched fraction was performed for XAC cells grown in pathogenicity-inducing (XAM-M) and pathogenicity-non-inducing (nutrient broth) media using two-dimensional electrophoresis combined with liquid chromatography-tandem mass spectrometry. Amongst the 40 proteins identified, transglycosylase was detected in a highly abundant spot in XAC cells grown under inducing condition. Additional up-regulated proteins related to cellular envelope metabolism included glucose-1-phosphate thymidylyltransferase, dTDP-4-dehydrorhamnose-3,5-epimerase and peptidyl-prolyl cis-trans-isomerase. Phosphoglucomutase and superoxide dismutase proteins, known to be involved in pathogenicity in other Xanthomonas species or organisms, were also detected. Western blot and quantitative real-time polymerase chain reaction analyses for transglycosylase and superoxide dismutase confirmed that these proteins were up-regulated under inducing condition, consistent with the proteomic results. Multiple spots for the 60-kDa chaperonin and glyceraldehyde-3-phosphate dehydrogenase were identified, suggesting the presence of post-translational modifications. We propose that substantial alterations in cellular envelope metabolism occur during the XAC infectious process, which are related to several aspects, from defence against reactive oxygen species to exopolysaccharide synthesis. Our results provide new candidates for virulence-related proteins, whose abundance correlates with the induction of pathogenicity and virulence genes, such as hrpD6, hrpG, hrpB7, hpa1 and hrpX. The results present new potential targets against XAC to be investigated in further functional studies.
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Affiliation(s)
- Juliana Artier
- Laboratório de Bioquímica e Biologia Molecular Aplicada, Departamento de Genética e EvoluçãoUniversidade Federal de São Carlos, UFSCarSão CarlosSP13565‐905Brazil
| | - Flávia da Silva Zandonadi
- Laboratório de Bioquímica e Biologia Molecular Aplicada, Departamento de Genética e EvoluçãoUniversidade Federal de São Carlos, UFSCarSão CarlosSP13565‐905Brazil
| | - Flávia Maria de Souza Carvalho
- Departamento de Tecnologia, Faculdade de Ciências Agrárias e Veterinárias de Jaboticabal, UNESPUniversidade Estadual PaulistaJaboticabalSP14884‐900Brazil
| | - Bianca Alves Pauletti
- LNBio, CNPEMLaboratório de Espectrometria de Massas, Laboratório Nacional de BiociênciasCampinasSP13083‐970Brazil
| | - Adriana Franco Paes Leme
- LNBio, CNPEMLaboratório de Espectrometria de Massas, Laboratório Nacional de BiociênciasCampinasSP13083‐970Brazil
| | - Carolina Moretto Carnielli
- Laboratório de Bioquímica e Biologia Molecular Aplicada, Departamento de Genética e EvoluçãoUniversidade Federal de São Carlos, UFSCarSão CarlosSP13565‐905Brazil
| | | | - Maria Célia Bertolini
- Departamento de Bioquímica e Tecnologia Química, Instituto de Química, UNESPUniversidade Estadual PaulistaAraraquaraSP14800‐060Brazil
| | - Jesus Aparecido Ferro
- Departamento de Tecnologia, Faculdade de Ciências Agrárias e Veterinárias de Jaboticabal, UNESPUniversidade Estadual PaulistaJaboticabalSP14884‐900Brazil
| | - José Belasque Júnior
- Departamento de Fitopatologia e Nematologia, Escola Superior de Agricultura ‘Luiz de Queiroz’Universidade de São PauloPiracicabaSP13418‐900Brazil
| | - Julio Cezar Franco de Oliveira
- Laboratório de Interações Microbianas, Departamento de Ciências BiológicasUniversidade Federal de São Paulo, UNIFESPDiademaSP09913‐030Brazil
| | - Maria Teresa Marques Novo‐Mansur
- Laboratório de Bioquímica e Biologia Molecular Aplicada, Departamento de Genética e EvoluçãoUniversidade Federal de São Carlos, UFSCarSão CarlosSP13565‐905Brazil
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25
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Moreira LM, Soares MR, Facincani AP, Ferreira CB, Ferreira RM, Ferro MIT, Gozzo FC, Felestrino ÉB, Assis RAB, Garcia CCM, Setubal JC, Ferro JA, de Oliveira JCF. Proteomics-based identification of differentially abundant proteins reveals adaptation mechanisms of Xanthomonas citri subsp. citri during Citrus sinensis infection. BMC Microbiol 2017; 17:155. [PMID: 28693412 PMCID: PMC5504864 DOI: 10.1186/s12866-017-1063-x] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2016] [Accepted: 07/01/2017] [Indexed: 12/11/2022] Open
Abstract
BACKGROUND Xanthomonas citri subsp. citri (Xac) is the causal agent of citrus canker. A proteomic analysis under in planta infectious and non-infectious conditions was conducted in order to increase our knowledge about the adaptive process of Xac during infection. RESULTS For that, a 2D-based proteomic analysis of Xac at 1, 3 and 5 days after inoculation, in comparison to Xac growth in NB media was carried out and followed by MALDI-TOF-TOF identification of 124 unique differentially abundant proteins. Among them, 79 correspond to up-regulated proteins in at least one of the three stages of infection. Our results indicate an important role of proteins related to biofilm synthesis, lipopolysaccharides biosynthesis, and iron uptake and metabolism as possible modulators of plant innate immunity, and revealed an intricate network of proteins involved in reactive oxygen species adaptation during Plants` Oxidative Burst response. We also identified proteins previously unknown to be involved in Xac-Citrus interaction, including the hypothetical protein XAC3981. A mutant strain for this gene has proved to be non-pathogenic in respect to classical symptoms of citrus canker induced in compatible plants. CONCLUSIONS This is the first time that a protein repertoire is shown to be active and working in an integrated manner during the infection process in a compatible host, pointing to an elaborate mechanism for adaptation of Xac once inside the plant.
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Affiliation(s)
- Leandro M Moreira
- Departamento de Ciências Biológicas (DECBI), Instituto de Ciências Exatas e Biológicas (ICEB), Universidade Federal de Ouro Preto (UFOP), Ouro Preto, MG, Brazil. .,Núcleo de Pesquisas em Ciências Biológicas (NUPEB), Universidade Federal de Ouro Preto, Ouro Preto, MG, Brazil.
| | - Márcia R Soares
- Departamento de Bioquímica (DBq), Instituto de Química (IQ), Universidade Federal do Rio de Janeiro (UFRJ), Rio de Janeiro, RJ, Brazil
| | - Agda P Facincani
- Faculdade de Ciências Agrárias e Veterinárias de Jaboticabal, UNESP - Universidade Estadual Paulista, Departamento de Tecnologia, Jaboticabal, SP, Brazil.
| | - Cristiano B Ferreira
- Faculdade de Ciências Agrárias e Veterinárias de Jaboticabal, UNESP - Universidade Estadual Paulista, Departamento de Tecnologia, Jaboticabal, SP, Brazil
| | - Rafael M Ferreira
- Faculdade de Ciências Agrárias e Veterinárias de Jaboticabal, UNESP - Universidade Estadual Paulista, Departamento de Tecnologia, Jaboticabal, SP, Brazil
| | - Maria I T Ferro
- Faculdade de Ciências Agrárias e Veterinárias de Jaboticabal, UNESP - Universidade Estadual Paulista, Departamento de Tecnologia, Jaboticabal, SP, Brazil
| | - Fábio C Gozzo
- Instituto de Química, Universidade Estadual de Campinas (UNICAMP), Campinas, SP, Brazil
| | - Érica B Felestrino
- Núcleo de Pesquisas em Ciências Biológicas (NUPEB), Universidade Federal de Ouro Preto, Ouro Preto, MG, Brazil
| | - Renata A B Assis
- Núcleo de Pesquisas em Ciências Biológicas (NUPEB), Universidade Federal de Ouro Preto, Ouro Preto, MG, Brazil
| | - Camila Carrião M Garcia
- Departamento de Ciências Biológicas (DECBI), Instituto de Ciências Exatas e Biológicas (ICEB), Universidade Federal de Ouro Preto (UFOP), Ouro Preto, MG, Brazil.,Núcleo de Pesquisas em Ciências Biológicas (NUPEB), Universidade Federal de Ouro Preto, Ouro Preto, MG, Brazil
| | - João C Setubal
- Departamento de Bioquímica (DB), Instituto de Química (IQ), Universidade de São Paulo (USP), São Paulo, SP, Brazil.,Biocomplexity Institute, Virginia Tech, Blacksburg, VA, USA
| | - Jesus A Ferro
- Faculdade de Ciências Agrárias e Veterinárias de Jaboticabal, UNESP - Universidade Estadual Paulista, Departamento de Tecnologia, Jaboticabal, SP, Brazil
| | - Julio C F de Oliveira
- Departamento de Ciências Biológicas (DCB), Universidade Federal de São Paulo (UNIFESP), Diadema, SP, Brazil
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26
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Ficarra FA, Grandellis C, Galván EM, Ielpi L, Feil R, Lunn JE, Gottig N, Ottado J. Xanthomonas citri ssp. citri requires the outer membrane porin OprB for maximal virulence and biofilm formation. MOLECULAR PLANT PATHOLOGY 2017; 18:720-733. [PMID: 27226289 PMCID: PMC6638224 DOI: 10.1111/mpp.12433] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/15/2016] [Revised: 05/04/2016] [Accepted: 05/23/2016] [Indexed: 05/31/2023]
Abstract
Xanthomonas citri ssp. citri (Xcc) causes canker disease in citrus, and biofilm formation is critical for the disease cycle. OprB (Outer membrane protein B) has been shown previously to be more abundant in Xcc biofilms compared with the planktonic state. In this work, we showed that the loss of OprB in an oprB mutant abolishes bacterial biofilm formation and adherence to the host, and also compromises virulence and efficient epiphytic survival of the bacteria. Moreover, the oprB mutant is impaired in bacterial stress resistance. OprB belongs to a family of carbohydrate transport proteins, and the uptake of glucose is decreased in the mutant strain, indicating that OprB transports glucose. Loss of OprB leads to increased production of xanthan exopolysaccharide, and the carbohydrate intermediates of xanthan biosynthesis are also elevated in the mutant. The xanthan produced by the mutant has a higher viscosity and, unlike wild-type xanthan, completely lacks pyruvylation. Overall, these results suggest that Xcc reprogrammes its carbon metabolism when it senses a shortage of glucose input. The participation of OprB in the process of biofilm formation and virulence, as well as in metabolic changes to redirect the carbon flux, is discussed. Our results demonstrate the importance of environmental nutrient supply and glucose uptake via OprB for Xcc virulence.
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Affiliation(s)
- Florencia A. Ficarra
- Instituto de Biología Molecular y Celular de Rosario, Consejo Nacional de Investigaciones Científicas y Técnicas (IBR‐CONICET) and Facultad de Ciencias Bioquímicas y FarmacéuticasUniversidad Nacional de Rosario, Ocampo y EsmeraldaRosario2000Argentina
| | - Carolina Grandellis
- Instituto de Biología Molecular y Celular de Rosario, Consejo Nacional de Investigaciones Científicas y Técnicas (IBR‐CONICET) and Facultad de Ciencias Bioquímicas y FarmacéuticasUniversidad Nacional de Rosario, Ocampo y EsmeraldaRosario2000Argentina
| | - Estela M. Galván
- Laboratory of Bacterial GeneticsFundación Instituto Leloir, IIBBA‐CONICET (C1405BWE)Ciudad de Buenos AiresBuenos AiresArgentina
| | - Luis Ielpi
- Laboratory of Bacterial GeneticsFundación Instituto Leloir, IIBBA‐CONICET (C1405BWE)Ciudad de Buenos AiresBuenos AiresArgentina
| | - Regina Feil
- Max Planck Institute of Molecular Plant PhysiologyWissenschaftspark Potsdam‐GolmAm Mühlenberg 114476 Potsdam‐GolmGermany
| | - John E. Lunn
- Max Planck Institute of Molecular Plant PhysiologyWissenschaftspark Potsdam‐GolmAm Mühlenberg 114476 Potsdam‐GolmGermany
| | - Natalia Gottig
- Instituto de Biología Molecular y Celular de Rosario, Consejo Nacional de Investigaciones Científicas y Técnicas (IBR‐CONICET) and Facultad de Ciencias Bioquímicas y FarmacéuticasUniversidad Nacional de Rosario, Ocampo y EsmeraldaRosario2000Argentina
| | - Jorgelina Ottado
- Instituto de Biología Molecular y Celular de Rosario, Consejo Nacional de Investigaciones Científicas y Técnicas (IBR‐CONICET) and Facultad de Ciencias Bioquímicas y FarmacéuticasUniversidad Nacional de Rosario, Ocampo y EsmeraldaRosario2000Argentina
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27
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Chen T, Duan L, Zhou B, Yu H, Zhu H, Cao Y, Zhang Z. Interplay of Pathogen-Induced Defense Responses and Symbiotic Establishment in Medicago truncatula. Front Microbiol 2017; 8:973. [PMID: 28611764 PMCID: PMC5447765 DOI: 10.3389/fmicb.2017.00973] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2017] [Accepted: 05/15/2017] [Indexed: 12/30/2022] Open
Abstract
Suppression of host innate immunity appears to be required for the establishment of symbiosis between rhizobia and host plants. In this study, we established a system that included a host plant, a bacterial pathogen and a symbiotic rhizobium to study the role of innate immunity during symbiotic interactions. A pathogenic bacterium, Pseudomonas syringae pv. tomato strain DC3000 (Pst DC3000), was shown to cause chlorosis in Medicago truncatula A17. Sinorhizobium meliloti strain Sm2011 (Sm2011) and Pst DC3000 strain alone induced similar defense responses in M. truncatula. However, when co-inoculated, Sm2011 specifically suppressed the defense responses induced by Pst DC3000, such as MAPK activation and ROS production. Inoculation with Sm2011 suppressed the transcription of defense-related genes triggered by Pst DC3000 infection, including the receptor of bacterial flagellin (FLS2), pathogenesis-related protein 10 (PR10), and the transcription factor WRKY33. Interestingly, inoculation with Pst DC3000 specifically inhibited the expression of the symbiosis marker genes nodule inception and nodulation pectate lyase and reduced the numbers of infection threads and nodules on M. truncatula A17 roots, indicating that Pst DC3000 inhibits the establishment of symbiosis in M. truncatula. In addition, defense-related genes, such as MAPK3/6, RbohC, and WRKY33, exhibited a transient increase in their expression in the early stage of symbiosis with Sm2011, but the expression dropped down to normal levels at later symbiotic stages. Our results suggest that plant innate immunity plays an antagonistic role in symbiosis by directly reducing the numbers of infection threads and nodules.
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Affiliation(s)
- Tao Chen
- State Key Laboratory of Agricultural Microbiology, Huazhong Agricultural UniversityWuhan, China.,The Provincial Key Laboratory of Plant Pathology of Hubei Province, College of Plant Science and Technology, Huazhong Agricultural UniversityWuhan, China
| | - Liujian Duan
- State Key Laboratory of Agricultural Microbiology, Huazhong Agricultural UniversityWuhan, China
| | - Bo Zhou
- State Key Laboratory of Agricultural Microbiology, Huazhong Agricultural UniversityWuhan, China
| | - Haixiang Yu
- State Key Laboratory of Agricultural Microbiology, Huazhong Agricultural UniversityWuhan, China
| | - Hui Zhu
- State Key Laboratory of Agricultural Microbiology, Huazhong Agricultural UniversityWuhan, China
| | - Yangrong Cao
- State Key Laboratory of Agricultural Microbiology, Huazhong Agricultural UniversityWuhan, China
| | - Zhongming Zhang
- State Key Laboratory of Agricultural Microbiology, Huazhong Agricultural UniversityWuhan, China
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Di Lorenzo F, Silipo A, Andersen Gersby LB, Palmigiano A, Lanzetta R, Garozzo D, Boyer C, Pruvost O, Newman MA, Molinaro A. Xanthomonas citri pv. citri Pathotypes: LPS Structure and Function as Microbe-Associated Molecular Patterns. Chembiochem 2017; 18:772-781. [PMID: 28186388 DOI: 10.1002/cbic.201600671] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2016] [Indexed: 12/13/2022]
Abstract
Xanthomonas citri pv. citri is the pathogen responsible for Asiatic citrus canker, one of the most serious citrus diseases worldwide. The lipopolysaccharide (LPS) molecule has been demonstrated to be involved in X. citri pv. citri virulence. Despite enormous progress in investigations of the molecular mechanisms for bacterial pathogenicity, determination of the detailed LPS structure-activity relationship is limited, as the current knowledge is mainly based on structural determination of one X. citri pv. citri strain. As X. citri pv. citri strains are distinguished into three main pathogenicity groups, we characterized the full structure of the LPS from two pathotypes that differ in their host-range specificity. This revealed an intriguing difference in LPS O-chain structure. We also tested the LPSs and isolated lipid A moieties for their ability to act as microbe-associated molecular patterns in Arabidopsis thaliana. Both LPS/lipid As induced ROS accumulation, but no difference was observed between the two pathotypes.
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Affiliation(s)
- Flaviana Di Lorenzo
- Department of Chemical Sciences, University of Naples Federico II, via Cinthia 4, 80126, Naples, Italy
| | - Alba Silipo
- Department of Chemical Sciences, University of Naples Federico II, via Cinthia 4, 80126, Naples, Italy
| | | | - Angelo Palmigiano
- CNR-Istituto per i Polimeri, Compositi e Biomateriali IPCB, via Gaifami 18, 95126, Catania, Italy
| | - Rosa Lanzetta
- Department of Chemical Sciences, University of Naples Federico II, via Cinthia 4, 80126, Naples, Italy
| | - Domenico Garozzo
- CNR-Istituto per i Polimeri, Compositi e Biomateriali IPCB, via Gaifami 18, 95126, Catania, Italy
| | - Claudine Boyer
- CIRAD, UMR Peuplements Végétaux et Bioagresseurs en Milieu Tropical (PVBMT), Saint Pierre, La Réunion, France
| | - Olivier Pruvost
- CIRAD, UMR Peuplements Végétaux et Bioagresseurs en Milieu Tropical (PVBMT), Saint Pierre, La Réunion, France
| | - Mari-Anne Newman
- Department of Plant and Environmental Sciences, University of Copenhagen, 1871, Frederiksberg, Copenhagen, Denmark
| | - Antonio Molinaro
- Department of Chemical Sciences, University of Naples Federico II, via Cinthia 4, 80126, Naples, Italy
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Dalio RJD, Magalhães DM, Rodrigues CM, Arena GD, Oliveira TS, Souza-Neto RR, Picchi SC, Martins PMM, Santos PJC, Maximo HJ, Pacheco IS, De Souza AA, Machado MA. PAMPs, PRRs, effectors and R-genes associated with citrus-pathogen interactions. ANNALS OF BOTANY 2017; 119:749-774. [PMID: 28065920 PMCID: PMC5571375 DOI: 10.1093/aob/mcw238] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/09/2016] [Revised: 07/08/2016] [Accepted: 10/22/2016] [Indexed: 05/08/2023]
Abstract
BACKGROUND Recent application of molecular-based technologies has considerably advanced our understanding of complex processes in plant-pathogen interactions and their key components such as PAMPs, PRRs, effectors and R-genes. To develop novel control strategies for disease prevention in citrus, it is essential to expand and consolidate our knowledge of the molecular interaction of citrus plants with their pathogens. SCOPE This review provides an overview of our understanding of citrus plant immunity, focusing on the molecular mechanisms involved in the interactions with viruses, bacteria, fungi, oomycetes and vectors related to the following diseases: tristeza, psorosis, citrus variegated chlorosis, citrus canker, huanglongbing, brown spot, post-bloom, anthracnose, gummosis and citrus root rot.
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Affiliation(s)
- Ronaldo J. D. Dalio
- Citrus Biotechnology Lab, Centro de Citricultura Sylvio Moreira, IAC, Cordeirópolis-SP, Brazil
| | - Diogo M. Magalhães
- Citrus Biotechnology Lab, Centro de Citricultura Sylvio Moreira, IAC, Cordeirópolis-SP, Brazil
| | - Carolina M. Rodrigues
- Citrus Biotechnology Lab, Centro de Citricultura Sylvio Moreira, IAC, Cordeirópolis-SP, Brazil
| | - Gabriella D. Arena
- Citrus Biotechnology Lab, Centro de Citricultura Sylvio Moreira, IAC, Cordeirópolis-SP, Brazil
| | - Tiago S. Oliveira
- Citrus Biotechnology Lab, Centro de Citricultura Sylvio Moreira, IAC, Cordeirópolis-SP, Brazil
| | - Reinaldo R. Souza-Neto
- Citrus Biotechnology Lab, Centro de Citricultura Sylvio Moreira, IAC, Cordeirópolis-SP, Brazil
| | - Simone C. Picchi
- Citrus Biotechnology Lab, Centro de Citricultura Sylvio Moreira, IAC, Cordeirópolis-SP, Brazil
| | - Paula M. M. Martins
- Citrus Biotechnology Lab, Centro de Citricultura Sylvio Moreira, IAC, Cordeirópolis-SP, Brazil
| | - Paulo J. C. Santos
- Citrus Biotechnology Lab, Centro de Citricultura Sylvio Moreira, IAC, Cordeirópolis-SP, Brazil
| | - Heros J. Maximo
- Citrus Biotechnology Lab, Centro de Citricultura Sylvio Moreira, IAC, Cordeirópolis-SP, Brazil
| | - Inaiara S. Pacheco
- Citrus Biotechnology Lab, Centro de Citricultura Sylvio Moreira, IAC, Cordeirópolis-SP, Brazil
| | - Alessandra A. De Souza
- Citrus Biotechnology Lab, Centro de Citricultura Sylvio Moreira, IAC, Cordeirópolis-SP, Brazil
| | - Marcos A. Machado
- Citrus Biotechnology Lab, Centro de Citricultura Sylvio Moreira, IAC, Cordeirópolis-SP, Brazil
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Petrocelli S, Arana MR, Cabrini MN, Casabuono AC, Moyano L, Beltramino M, Moreira LM, Couto AS, Orellano EG. Deletion of pilA, a Minor Pilin-Like Gene, from Xanthomonas citri subsp. citri Influences Bacterial Physiology and Pathogenesis. Curr Microbiol 2016; 73:904-914. [PMID: 27664015 DOI: 10.1007/s00284-016-1138-1] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2016] [Accepted: 09/13/2016] [Indexed: 10/21/2022]
Abstract
Type IV pili (Tfp) are widely distributed adhesins of bacterial surfaces. In plant pathogenic bacteria, Tfp are involved in host colonization and pathogenesis. Xanthomonas citri subsp. citri (Xcc) is the phytopathogen responsible for citrus canker disease. In this work, three Tfp structural genes, fimA, fimA1, and pilA from Xcc were studied. A pilA mutant strain from Xcc (XccΔpilA) was constructed and differences in physiological features, such as motilities, adhesion, and biofilm formation, were observed. A structural study of the purified Tfp fractions from Xcc wild-type and Xcc∆pilA showed that pilins are glycosylated in both strains and that FimA and FimA1 are the main structural components of the pili. Furthermore, smaller lesion symptoms and reduced bacterial growth were produced by Xcc∆pilA in orange plants compared to the wild-type strain. These results indicate that the minor pilin-like gene, pilA, is involved in Tfp performance during the infection process.
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Affiliation(s)
- Silvana Petrocelli
- Facultad de Ciencias Bioquímicas y Farmacéuticas, Instituto de Biología Molecular y Celular de Rosario (IBR), Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Universidad Nacional de Rosario, Suipacha 531, S2002LRK, Rosario, Argentina
| | - Maite R Arana
- Facultad de Ciencias Bioquímicas y Farmacéuticas, Instituto de Biología Molecular y Celular de Rosario (IBR), Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Universidad Nacional de Rosario, Suipacha 531, S2002LRK, Rosario, Argentina
| | - Marcela N Cabrini
- Departamento de Química Orgánica, Facultad de Ciencias Exactas y Naturales, Centro de Investigaciones en Hidratos de Carbono, Universidad de Buenos Aires, 1428, Buenos Aires, Argentina
| | - Adriana C Casabuono
- Departamento de Química Orgánica, Facultad de Ciencias Exactas y Naturales, Centro de Investigaciones en Hidratos de Carbono, Universidad de Buenos Aires, 1428, Buenos Aires, Argentina
| | - Laura Moyano
- Facultad de Ciencias Bioquímicas y Farmacéuticas, Instituto de Biología Molecular y Celular de Rosario (IBR), Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Universidad Nacional de Rosario, Suipacha 531, S2002LRK, Rosario, Argentina
| | - Matías Beltramino
- Facultad de Ciencias Bioquímicas y Farmacéuticas, Instituto de Biología Molecular y Celular de Rosario (IBR), Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Universidad Nacional de Rosario, Suipacha 531, S2002LRK, Rosario, Argentina
| | - Leandro M Moreira
- Departamento de Ciências Biológicas (DECBI), Instituto de Ciências Exatas e Biológicas, Campus Morro do Cruzeiro, Universidade Federal de Ouro Preto, Ouro Preto, MG, Brazil
- Núcleo de Pesquisas em Ciências Biológicas (NUPEB), Universidade Federal de Ouro Preto, Ouro Preto, MG, Brazil
| | - Alicia S Couto
- Departamento de Química Orgánica, Facultad de Ciencias Exactas y Naturales, Centro de Investigaciones en Hidratos de Carbono, Universidad de Buenos Aires, 1428, Buenos Aires, Argentina
| | - Elena G Orellano
- Facultad de Ciencias Bioquímicas y Farmacéuticas, Instituto de Biología Molecular y Celular de Rosario (IBR), Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Universidad Nacional de Rosario, Suipacha 531, S2002LRK, Rosario, Argentina.
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Zhang Y, Jalan N, Zhou X, Goss E, Jones JB, Setubal JC, Deng X, Wang N. Positive selection is the main driving force for evolution of citrus canker-causing Xanthomonas. THE ISME JOURNAL 2015; 9:2128-38. [PMID: 25689023 PMCID: PMC4579464 DOI: 10.1038/ismej.2015.15] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/03/2014] [Revised: 12/29/2014] [Accepted: 01/06/2015] [Indexed: 12/13/2022]
Abstract
Understanding the evolutionary history and potential of bacterial pathogens is critical to prevent the emergence of new infectious bacterial diseases. Xanthomonas axonopodis subsp. citri (Xac) (synonym X. citri subsp. citri), which causes citrus canker, is one of the hardest-fought plant bacterial pathogens in US history. Here, we sequenced 21 Xac strains (14 XacA, 3 XacA* and 4 XacA(w)) with different host ranges from North America and Asia and conducted comparative genomic and evolutionary analyses. Our analyses suggest that acquisition of beneficial genes and loss of detrimental genes most likely allowed XacA to infect a broader range of hosts as compared with XacA(w) and XacA*. Recombination was found to have occurred frequently on the relative ancient branches, but rarely on the young branches of the clonal genealogy. The ratio of recombination/mutation ρ/θ was 0.0790±0.0005, implying that the Xac population was clonal in structure. Positive selection has affected 14% (395 out of 2822) of core genes of the citrus canker-causing Xanthomonas. The genes affected are enriched in 'carbohydrate transport and metabolism' and 'DNA replication, recombination and repair' genes (P<0.05). Many genes related to virulence, especially genes involved in the type III secretion system and effectors, are affected by positive selection, further highlighting the contribution of positive selection to the evolution of citrus canker-causing Xanthomonas. Our results suggest that both metabolism and virulence genes provide advantages to endow XacA with higher virulence and a wider host range. Our analysis advances our understanding of the genomic basis of specialization by positive selection in bacterial evolution.
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Affiliation(s)
- Yunzeng Zhang
- Citrus Research and Education Center, Department of Microbiology and Cell Science, University of Florida, Lake Alfred, FL, USA
| | - Neha Jalan
- Citrus Research and Education Center, Department of Microbiology and Cell Science, University of Florida, Lake Alfred, FL, USA
| | - Xiaofeng Zhou
- Citrus Research and Education Center, Department of Microbiology and Cell Science, University of Florida, Lake Alfred, FL, USA
| | - Erica Goss
- Department of Plant Pathology, University of Florida, Gainesville, FL, USA
| | - Jeffrey B Jones
- Department of Plant Pathology, University of Florida, Gainesville, FL, USA
| | - João C Setubal
- Departamento de Bioquímica, Instituto de Química, Universidade de São Paulo, São Paulo, Brazil
| | - Xiaoling Deng
- Department of Plant Pathology, South China Agricultural University, Guangzhou, Guangdong, China
| | - Nian Wang
- Citrus Research and Education Center, Department of Microbiology and Cell Science, University of Florida, Lake Alfred, FL, USA
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O antigen modulates insect vector acquisition of the bacterial plant pathogen Xylella fastidiosa. Appl Environ Microbiol 2015; 81:8145-54. [PMID: 26386068 DOI: 10.1128/aem.02383-15] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2015] [Accepted: 09/14/2015] [Indexed: 11/20/2022] Open
Abstract
Hemipteran insect vectors transmit the majority of plant pathogens. Acquisition of pathogenic bacteria by these piercing/sucking insects requires intimate associations between the bacterial cells and insect surfaces. Lipopolysaccharide (LPS) is the predominant macromolecule displayed on the cell surface of Gram-negative bacteria and thus mediates bacterial interactions with the environment and potential hosts. We hypothesized that bacterial cell surface properties mediated by LPS would be important in modulating vector-pathogen interactions required for acquisition of the bacterial plant pathogen Xylella fastidiosa, the causative agent of Pierce's disease of grapevines. Utilizing a mutant that produces truncated O antigen (the terminal portion of the LPS molecule), we present results that link this LPS structural alteration to a significant decrease in the attachment of X. fastidiosa to blue-green sharpshooter foreguts. Scanning electron microscopy confirmed that this defect in initial attachment compromised subsequent biofilm formation within vector foreguts, thus impairing pathogen acquisition. We also establish a relationship between O antigen truncation and significant changes in the physiochemical properties of the cell, which in turn affect the dynamics of X. fastidiosa adhesion to the vector foregut. Lastly, we couple measurements of the physiochemical properties of the cell with hydrodynamic fluid shear rates to produce a Comsol model that predicts primary areas of bacterial colonization within blue-green sharpshooter foreguts, and we present experimental data that support the model. These results demonstrate that, in addition to reported protein adhesin-ligand interactions, O antigen is crucial for vector-pathogen interactions, specifically in the acquisition of this destructive agricultural pathogen.
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Pieretti I, Cociancich S, Bolot S, Carrère S, Morisset A, Rott P, Royer M. Full Genome Sequence Analysis of Two Isolates Reveals a Novel Xanthomonas Species Close to the Sugarcane Pathogen Xanthomonas albilineans. Genes (Basel) 2015; 6:714-33. [PMID: 26213974 PMCID: PMC4584326 DOI: 10.3390/genes6030714] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2015] [Revised: 07/03/2015] [Accepted: 07/14/2015] [Indexed: 12/28/2022] Open
Abstract
Xanthomonas albilineans is the bacterium responsible for leaf scald, a lethal disease of sugarcane. Within the Xanthomonas genus, X. albilineans exhibits distinctive genomic characteristics including the presence of significant genome erosion, a non-ribosomal peptide synthesis (NRPS) locus involved in albicidin biosynthesis, and a type 3 secretion system (T3SS) of the Salmonella pathogenicity island-1 (SPI-1) family. We sequenced two X. albilineans-like strains isolated from unusual environments, i.e., from dew droplets on sugarcane leaves and from the wild grass Paspalum dilatatum, and compared these genomes sequences with those of two strains of X. albilineans and three of Xanthomonas sacchari. Average nucleotide identity (ANI) and multi-locus sequence analysis (MLSA) showed that both X. albilineans-like strains belong to a new species close to X. albilineans that we have named "Xanthomonas pseudalbilineans". X. albilineans and "X. pseudalbilineans" share many genomic features including (i) the lack of genes encoding a hypersensitive response and pathogenicity type 3 secretion system (Hrp-T3SS), and (ii) genome erosion that probably occurred in a common progenitor of both species. Our comparative analyses also revealed specific genomic features that may help X. albilineans interact with sugarcane, e.g., a PglA endoglucanase, three TonB-dependent transporters and a glycogen metabolism gene cluster. Other specific genomic features found in the "X. pseudalbilineans" genome may contribute to its fitness and specific ecological niche.
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Affiliation(s)
- Isabelle Pieretti
- CIRAD UMR BGPI, TA A-54/K, Campus International de Baillarguet, F-34398 Montpellier Cedex 5, France.
| | - Stéphane Cociancich
- CIRAD UMR BGPI, TA A-54/K, Campus International de Baillarguet, F-34398 Montpellier Cedex 5, France.
| | - Stéphanie Bolot
- INRA, Laboratoire des Interactions Plantes-Microorganismes (LIPM), UMR441, 24 Chemin de Borde Rouge-Auzeville CS52627, F-31326 Castanet Tolosan Cedex, France.
- CNRS, Laboratoire des Interactions Plantes-Microorganismes (LIPM), UMR2594, 24 Chemin de Borde Rouge-Auzeville CS52627, F-31326 Castanet Tolosan Cedex, France.
| | - Sébastien Carrère
- INRA, Laboratoire des Interactions Plantes-Microorganismes (LIPM), UMR441, 24 Chemin de Borde Rouge-Auzeville CS52627, F-31326 Castanet Tolosan Cedex, France.
- CNRS, Laboratoire des Interactions Plantes-Microorganismes (LIPM), UMR2594, 24 Chemin de Borde Rouge-Auzeville CS52627, F-31326 Castanet Tolosan Cedex, France.
| | - Alexandre Morisset
- CIRAD UMR BGPI, TA A-54/K, Campus International de Baillarguet, F-34398 Montpellier Cedex 5, France.
| | - Philippe Rott
- CIRAD UMR BGPI, TA A-54/K, Campus International de Baillarguet, F-34398 Montpellier Cedex 5, France.
| | - Monique Royer
- CIRAD UMR BGPI, TA A-54/K, Campus International de Baillarguet, F-34398 Montpellier Cedex 5, France.
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Luo L, Lu D. Immunosuppression during Rhizobium-legume symbiosis. PLANT SIGNALING & BEHAVIOR 2014; 9:e28197. [PMID: 24556951 PMCID: PMC4091602 DOI: 10.4161/psb.28197] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/11/2014] [Revised: 02/12/2014] [Accepted: 02/12/2014] [Indexed: 05/24/2023]
Abstract
Rhizobium infects host legumes to elicit new plant organs, nodules where dinitrogen is fixed as ammonia that can be directly utilized by plants. The nodulation factor (NF) produced by Rhizobium is one of the determinant signals for rhizobial infection and nodule development. Recently, it was found to suppress the innate immunity on host and nonhost plants as well as its analogs, chitins. Therefore, NF can be recognized as a microbe/pathogen-associated molecular pattern (M/PAMP) like chitin to induce the M/PAMP triggered susceptibility (M/PTS) of host plants to rhizobia. Whether the NF signaling pathway is directly associated with the innate immunity is not clear till now. In fact, other MAMPs such as lipopolysaccharide (LPS), exopolysaccharide (EPS) and cyclic-β-glucan, together with type III secretion system (T3SS) effectors are also required for rhizobial infection or survival in leguminous nodule cells. Interestingly, most of them play similarly negative roles in the innate immunity of host plants, though their signaling is not completely elucidated. Taken together, we believe that the local immunosuppression on host plants induced by Rhizobium is essential for the establishment of their symbiosis.
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Affiliation(s)
- Li Luo
- Shanghai Key Lab of Bioenergy Plant School of Life Science; Shanghai University; Baoshan, Shanghai, PR China
- State Key Lab of Plant Molecular Genetics; Institute of Plant Physiology and Ecology; Shanghai Institutes for Biological Sciences; Chinese Academy of Sciences; Shanghai, PRChina
| | - Dawei Lu
- State Key Lab of Plant Molecular Genetics; Institute of Plant Physiology and Ecology; Shanghai Institutes for Biological Sciences; Chinese Academy of Sciences; Shanghai, PRChina
- School of Life Science; Anhui University; Heifei, Anhui, PR China
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Zimaro T, Thomas L, Marondedze C, Garavaglia BS, Gehring C, Ottado J, Gottig N. Insights into xanthomonas axonopodis pv. citri biofilm through proteomics. BMC Microbiol 2013; 13:186. [PMID: 23924281 PMCID: PMC3750573 DOI: 10.1186/1471-2180-13-186] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2013] [Accepted: 08/02/2013] [Indexed: 11/28/2022] Open
Abstract
Background Xanthomonas axonopodis pv. citri (X. a. pv. citri) causes citrus canker that can result in defoliation and premature fruit drop with significant production losses worldwide. Biofilm formation is an important process in bacterial pathogens and several lines of evidence suggest that in X. a. pv. citri this process is a requirement to achieve maximal virulence since it has a major role in host interactions. In this study, proteomics was used to gain further insights into the functions of biofilms. Results In order to identify differentially expressed proteins, a comparative proteomic study using 2D difference gel electrophoresis was carried out on X. a. pv. citri mature biofilm and planktonic cells. The biofilm proteome showed major variations in the composition of outer membrane proteins and receptor or transport proteins. Among them, several porins and TonB-dependent receptor were differentially regulated in the biofilm compared to the planktonic cells, indicating that these proteins may serve in maintaining specific membrane-associated functions including signaling and cellular homeostasis. In biofilms, UDP-glucose dehydrogenase with a major role in exopolysaccharide production and the non-fimbrial adhesin YapH involved in adherence were over-expressed, while a polynucleotide phosphorylase that was demonstrated to negatively control biofilm formation in E. coli was down-regulated. In addition, several proteins involved in protein synthesis, folding and stabilization were up-regulated in biofilms. Interestingly, some proteins related to energy production, such as ATP-synthase were down-regulated in biofilms. Moreover, a number of enzymes of the tricarboxylic acid cycle were differentially expressed. In addition, X. a. pv. citri biofilms also showed down-regulation of several antioxidant enzymes. The respective gene expression patterns of several identified proteins in both X. a. pv. citri mature biofilm and planktonic cells were evaluated by quantitative real-time PCR and shown to consistently correlate with those deduced from the proteomic study. Conclusions Differentially expressed proteins are enriched in functional categories. Firstly, proteins that are down-regulated in X. a. pv. citri biofilms are enriched for the gene ontology (GO) terms ‘generation of precursor metabolites and energy’ and secondly, the biofilm proteome mainly changes in ‘outer membrane and receptor or transport’. We argue that the differentially expressed proteins have a critical role in maintaining a functional external structure as well as enabling appropriate flow of nutrients and signals specific to the biofilm lifestyle.
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Affiliation(s)
- Tamara Zimaro
- Instituto de Biología Molecular y Celular de Rosario, Consejo Nacional de Investigaciones Científicas y Técnicas (IBR-CONICET), Ocampo y Esmeralda, Rosario, Santa Fe, Argentina
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Clifford JC, Rapicavoli JN, Roper MC. A rhamnose-rich O-antigen mediates adhesion, virulence, and host colonization for the xylem-limited phytopathogen Xylella fastidiosa. MOLECULAR PLANT-MICROBE INTERACTIONS : MPMI 2013; 26:676-85. [PMID: 23441576 DOI: 10.1094/mpmi-12-12-0283-r] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/19/2023]
Abstract
Xylella fastidiosa is a gram-negative, xylem-limited bacterium that causes a lethal disease of grapevine called Pierce's disease. Lipopolysaccharide (LPS) composes approximately 75% of the outer membrane of gram-negative bacteria and, because it is largely displayed on the cell surface, it mediates interactions between the bacterial cell and its surrounding environment. LPS is composed of a conserved lipid A-core oligosaccharide component and a variable O-antigen portion. By targeting a key O-antigen biosynthetic gene, we demonstrate the contribution of the rhamnose-rich O-antigen to surface attachment, cell-cell aggregation, and biofilm maturation: critical steps for successful infection of the host xylem tissue. Moreover, we have demonstrated that a fully formed O-antigen moiety is an important virulence factor for Pierce's disease development in grape and that depletion of the O-antigen compromises its ability to colonize the host. It has long been speculated that cell-surface polysaccharides play a role in X. fastidiosa virulence and this study confirms that LPS is a major virulence factor for this important agricultural pathogen.
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Affiliation(s)
- Jennifer C Clifford
- Department of Plant Pathology and Microbiology, University of California, Riverside, CA, USA
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Requirement of the lipopolysaccharide O-chain biosynthesis gene wxocB for type III secretion and virulence of Xanthomonas oryzae pv. Oryzicola. J Bacteriol 2013; 195:1959-69. [PMID: 23435979 DOI: 10.1128/jb.02299-12] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Xanthomonas oryzae pv. oryzicola causes bacterial leaf streak of rice. A mutant disrupted in wxocB, predicted to encode an enzyme for lipopolysaccharide (LPS) synthesis, was previously shown to suffer reduced virulence. Here, we confirm a role for wxocB in virulence and demonstrate its requirement for LPS O-chain assembly. Structure analysis indicated that wild-type LPS contains a polyrhamnose O chain with irregular, variant residues and a core oligosaccharide identical to that of other Xanthomonas spp. and that the wxocB mutant lacks the O chain. The mutant also showed moderate impairment in exopolysaccharide (EPS) production, but comparison with an EPS-deficient mutant demonstrated that this impairment could not account entirely for the reduced virulence. The wxocB mutant was not detectably different from the wild type in its induction of pathogenesis-related rice genes, type II secretion competence, flagellar motility, or resistance to two phytoalexins or resveratrol, and it was more, not less, resistant to oxidative stress and a third phytoalexin, indicating that none of these properties is involved. The mutant was more sensitive to SDS and to novobiocin, so increased sensitivity to some host-derived antimicrobials cannot be ruled out. However, the mutant showed a marked decrease in type III secretion into plant cells. This was not associated with any change in expression of genes for type III secretion or the ability to attach to plant cells in suspension. Thus, virulence of the wxocB mutant is likely reduced due primarily to a direct, possibly structural, effect of the loss of the O chain on type III delivery of effector proteins.
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