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Subedi A, Iruegas-Bocardo F, Luo L, Minsavage GV, Roberts PD, Jones JB, Goss EM. Amylase-associated genetic pattern in Xanthomonas euvesicatoria on pepper. Appl Environ Microbiol 2024:e0131324. [PMID: 39291986 DOI: 10.1128/aem.01313-24] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2024] [Accepted: 08/29/2024] [Indexed: 09/19/2024] Open
Abstract
Bacterial leaf spot of pepper (BSP), primarily caused by Xanthomonas euvesicatoria (Xe), poses a significant challenge to pepper production worldwide. Despite its impact, the genetic diversity of this pathogen remains underexplored, which limits our understanding of its population structure. To bridge this knowledge gap, we conducted a comprehensive analysis using 103 Xe strains isolated from pepper in southwest Florida to characterize genomic and type III effector (T3E) variation in this population. Phylogenetic analysis of core genomes revealed a major distinct genetic lineage associated with amylolytic activity. This amylolytic lineage was represented in Xe strains globally. Molecular clock analysis dated the emergence of amylolytic strains in Xe to around 1972. Notably, non-amylolytic strains possessed a single base pair frameshift deletion in the ⍺-amylase gene yet retained a conserved C-terminus. GUS assay revealed the expression of two open reading frames in non-amylolytic strains, one at the N-terminus and another that starts 136 base pairs upstream of the ⍺-amylase gene. Analysis of T3Es in the Florida Xe population identified variation in 12 effectors, including two classes of mutations in avrBs2 that prevent AvrBs2 from triggering a hypersensitive response in Bs2-resistant pepper plants. Knowledge of T3E variation could be used for effector-targeted disease management. This study revealed previously undescribed population structure in this economically important pathogen.IMPORTANCEBacterial leaf spot (BSP), a significant threat to pepper production globally, is primarily caused by Xanthomonas euvesicatoria (Xe). Limited genomic data has hindered detailed studies on its population diversity. This study analyzed the whole-genome sequences of 103 Xe strains from peppers in southwest Florida, along with additional global strains, to explore the pathogen's diversity. The study revealed two major distinct genetic groups based on their amylolytic activity, the ability to break down starch, with non-amylolytic strains having a mutation in the ⍺-amylase gene. Additionally, two classes of mutations in the avrBs2 gene were found, leading to susceptibility in pepper plants with the Bs2 resistance gene, a commercially available resistance gene for BSP. These findings highlight the need to forecast the emergence of such strains, identify genetic factors for innovative disease management, and understand how this pathogen evolves and spreads.
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Affiliation(s)
- Aastha Subedi
- Department of Plant Pathology, University of Florida, Gainesville, Florida, USA
| | | | - Laixin Luo
- Department of Plant Pathology, China Agricultural University, Beijing, China
| | - Gerald V Minsavage
- Department of Plant Pathology, University of Florida, Gainesville, Florida, USA
| | - Pamela D Roberts
- Southwest Florida Research & Education Center, University of Florida, Immokalee, Florida, USA
| | - Jeffrey B Jones
- Department of Plant Pathology, University of Florida, Gainesville, Florida, USA
| | - Erica M Goss
- Department of Plant Pathology, University of Florida, Gainesville, Florida, USA
- Emerging Pathogens Institute, University of Florida, Gainesville, Florida, USA
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Sivaraman S, Krishnamoorthy D, Arvind K, Grace T, Sharma J, Antony G. TAL effectors and the predicted host targets of pomegranate bacterial blight pathogen Xanthomonas citri pv. punicae. Curr Genet 2022; 68:361-373. [PMID: 35275250 DOI: 10.1007/s00294-022-01232-4] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2021] [Revised: 01/24/2022] [Accepted: 02/08/2022] [Indexed: 11/29/2022]
Abstract
The molecular mechanism of pomegranate susceptibility to bacterial blight, a serious threat to pomegranate production in India, is largely unknown. In the current study, we have used PacBio and Illumina sequencing of Xanthomonas citri pv. punicae (Xcp) strain 119 genome to identify tal genes and RNA-Seq analysis to identify putative host targets in the susceptible pomegranate variety Bhagwa challenged with Xcp119. Xcp119 genome encodes seven transcription activator-like effectors (TALEs), three of which are harbored by a plasmid. RVD-based phylogenetic analysis of TALEs of Xanthomonas citri pathovars indicate the TALEs of Xcp as evolutionarily and functionally close to Xanthomonas citri pv. malvacearum and Xanthomonas citri pv. glycines. Comparative RNA-Seq of Xcp and mock-inoculated leaf tissues revealed Xcp-induced pomegranate transcription modulation. The prediction of TALE binding elements (EBEs) in the promoters of up-regulated genes identified a set of TALE-targeted candidate genes in pomegranate-Xcp interaction. The predicted candidate susceptibility genes include two oxoglutarate-dependent dioxygenase gene, ethylene-responsive transcription factor and flavanone 3-hydroxylase-like gene, and the further characterization of these would enable blight resistance engineering in pomegranate.
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Affiliation(s)
- Sruthi Sivaraman
- Department of Plant Science, Central University of Kerala, Periye, 671320, Kerala, India
| | | | - Kumar Arvind
- Department of Genomic Science, Central University of Kerala, Periye, 671320, Kerala, India
| | - Tony Grace
- Department of Genomic Science, Central University of Kerala, Periye, 671320, Kerala, India
| | - Jyotsana Sharma
- ICAR-National Research Centre On Pomegranate, Kegaon, Solapur, 413255, Maharashtra, India
| | - Ginny Antony
- Department of Plant Science, Central University of Kerala, Periye, 671320, Kerala, India.
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Zhu S, Pan Y, Li K, Fan R, Xiang L, Huang S, Jia S, Niu X, Li C, Chen Y. Complete Genome Sequence of Xanthomonas phaseoli pv. manihotis Strain CHN01, the Causal Agent of Cassava Bacterial Blight. PLANT DISEASE 2022; 106:1039-1041. [PMID: 35259300 DOI: 10.1094/pdis-09-21-2016-a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Affiliation(s)
- Shousong Zhu
- Hainan Key Laboratory for Sustainable Utilization of Tropical Bioresource, College of Tropical Crops, Hainan University, Haikou 570228, Hainan, China
| | - Yueyun Pan
- Hainan Key Laboratory for Sustainable Utilization of Tropical Bioresource, College of Tropical Crops, Hainan University, Haikou 570228, Hainan, China
- Jiaxing Academy of Agricultural Science, Jiaxing 314016, Zhejiang, China
| | - Ke Li
- Hainan Key Laboratory for Sustainable Utilization of Tropical Bioresource, College of Tropical Crops, Hainan University, Haikou 570228, Hainan, China
| | - Ruochen Fan
- Hainan Key Laboratory for Sustainable Utilization of Tropical Bioresource, College of Tropical Crops, Hainan University, Haikou 570228, Hainan, China
| | - Li Xiang
- Hainan Key Laboratory for Sustainable Utilization of Tropical Bioresource, College of Tropical Crops, Hainan University, Haikou 570228, Hainan, China
| | - Siyuan Huang
- Hainan Key Laboratory for Sustainable Utilization of Tropical Bioresource, College of Tropical Crops, Hainan University, Haikou 570228, Hainan, China
| | - Suhang Jia
- Hainan Key Laboratory for Sustainable Utilization of Tropical Bioresource, College of Tropical Crops, Hainan University, Haikou 570228, Hainan, China
| | - Xiaolei Niu
- Hainan Key Laboratory for Sustainable Utilization of Tropical Bioresource, College of Tropical Crops, Hainan University, Haikou 570228, Hainan, China
| | - Chunxia Li
- Hainan Key Laboratory for Sustainable Utilization of Tropical Bioresource, College of Tropical Crops, Hainan University, Haikou 570228, Hainan, China
| | - Yinhua Chen
- College of Life Science, Hainan University, Haikou 570228, Hainan, China
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4
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Zhang H, Ye Z, Liu Z, Sun Y, Li X, Wu J, Zhou G, Wan Y. The Cassava NBS-LRR Genes Confer Resistance to Cassava Bacterial Blight. FRONTIERS IN PLANT SCIENCE 2022; 13:790140. [PMID: 35178059 PMCID: PMC8844379 DOI: 10.3389/fpls.2022.790140] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/06/2021] [Accepted: 01/07/2022] [Indexed: 05/25/2023]
Abstract
Cassava bacterial blight (CBB) caused by Xanthomonas axonopodis pv. manihotis (Xam) seriously affects cassava yield. Genes encoding nucleotide-binding site (NBS) and leucine-rich repeat (LRR) domains are among the most important disease resistance genes in plants that are specifically involved in the response to diverse pathogens. However, the in vivo roles of NBS-LRR remain unclear in cassava (Manihot esculenta). In this study, we isolated four MeLRR genes and assessed their expression under salicylic acid (SA) treatment and Xam inoculation. Four MeLRR genes positively regulate cassava disease general resistance against Xam via virus-induced gene silencing (VIGS) and transient overexpression. During cassava-Xam interaction, MeLRRs positively regulated endogenous SA and reactive oxygen species (ROS) accumulation and pathogenesis-related gene 1 (PR1) transcripts. Additionally, we revealed that MeLRRs positively regulated disease resistance in Arabidopsis. These pathogenic microorganisms include Pseudomonas syringae pv. tomato, Alternaria brassicicola, and Botrytis cinerea. Our findings shed light on the molecular mechanism underlying the regulation of cassava resistance against Xam inoculation.
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Affiliation(s)
- He Zhang
- Key Laboratory of Integrated Pest Management on Tropical Crops, Ministry of Agriculture and Rural Affairs, Environment and Plant Protection Institute, Chinese Academy of Tropical Agricultural Sciences, Haikou, China
- Hainan Key Laboratory for Sustainable Utilization of Tropical Bioresources, College of Tropical Crops, Hainan University, Haikou, China
| | - Zi Ye
- Key Laboratory of Integrated Pest Management on Tropical Crops, Ministry of Agriculture and Rural Affairs, Environment and Plant Protection Institute, Chinese Academy of Tropical Agricultural Sciences, Haikou, China
| | - Zhixin Liu
- Key Laboratory of Integrated Pest Management on Tropical Crops, Ministry of Agriculture and Rural Affairs, Environment and Plant Protection Institute, Chinese Academy of Tropical Agricultural Sciences, Haikou, China
| | - Yu Sun
- Key Laboratory of Integrated Pest Management on Tropical Crops, Ministry of Agriculture and Rural Affairs, Environment and Plant Protection Institute, Chinese Academy of Tropical Agricultural Sciences, Haikou, China
| | - Xinyu Li
- Hainan Key Laboratory for Sustainable Utilization of Tropical Bioresources, College of Tropical Crops, Hainan University, Haikou, China
| | - Jiao Wu
- Hainan Key Laboratory for Sustainable Utilization of Tropical Bioresources, College of Tropical Crops, Hainan University, Haikou, China
| | - Guangzhen Zhou
- Hainan Key Laboratory for Sustainable Utilization of Tropical Bioresources, College of Tropical Crops, Hainan University, Haikou, China
| | - Yinglang Wan
- Hainan Key Laboratory for Sustainable Utilization of Tropical Bioresources, College of Tropical Crops, Hainan University, Haikou, China
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Zárate‐Chaves CA, Gómez de la Cruz D, Verdier V, López CE, Bernal A, Szurek B. Cassava diseases caused by Xanthomonas phaseoli pv. manihotis and Xanthomonas cassavae. MOLECULAR PLANT PATHOLOGY 2021; 22:1520-1537. [PMID: 34227737 PMCID: PMC8578842 DOI: 10.1111/mpp.13094] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/06/2021] [Revised: 05/04/2021] [Accepted: 05/04/2021] [Indexed: 05/27/2023]
Abstract
Xanthomonas phaseoli pv. manihotis (Xpm) and X. cassavae (Xc) are two bacterial pathogens attacking cassava. Cassava bacterial blight (CBB) is a systemic disease caused by Xpm, which might have dramatic effects on plant growth and crop production. Cassava bacterial necrosis is a nonvascular disease caused by Xc with foliar symptoms similar to CBB, but its impacts on the plant vigour and the crop are limited. In this review, we describe the epidemiology and ecology of the two pathogens, the impacts and management of the diseases, and the main research achievements for each pathosystem. Because Xc data are sparse, our main focus is on Xpm and CBB.
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Affiliation(s)
| | | | - Valérie Verdier
- PHIMUniversité MontpellierCIRADINRAeIRDInstitut AgroMontpellierFrance
| | - Camilo E. López
- Manihot Biotec, Departamento de BiologíaUniversidad Nacional de ColombiaBogotáColombia
| | - Adriana Bernal
- Laboratorio de Interacciones Moleculares de Microorganismos AgrícolasDepartamento de Ciencias BásicasUniversidad de los AndesBogotáColombia
| | - Boris Szurek
- PHIMUniversité MontpellierCIRADINRAeIRDInstitut AgroMontpellierFrance
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Bragard C, Di Serio F, Gonthier P, Jaques Miret JA, Justesen AF, MacLeod A, Magnusson CS, Milonas P, Navas‐Cortes JA, Parnell S, Potting R, Thulke H, Van der Werf W, Civera AV, Yuen J, Zappalà L, Migheli Q, Stefani E, Vloutoglou I, Czwienczek E, Maiorano A, Streissl F, Reignault PL. Pest categorisation of Xanthomonas citri pv. viticola. EFSA J 2021; 19:e06929. [PMID: 34963789 PMCID: PMC8675326 DOI: 10.2903/j.efsa.2021.6929] [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] [Indexed: 12/03/2022] Open
Abstract
The EFSA Plant Health Panel performed a pest categorisation of Xanthomonas citri pv. viticola (Nayudu) Dye, a Gram-negative bacterium belonging to the Xanthomonadaceae family. The pathogen is a well-defined taxonomic unit and is the causal agent of the leaf spot and bacterial canker of Vitis vinifera. This bacterium is present in India and Brazil, where it affects table grape cultivation; the same pathogen is able to cause a disease on Azadirachta indica and on some weed species. Reports indicate that the bacterium is present in Thailand as well. The pathogen has never been reported from the EU territory and it is not included in EU Commission Implementing Regulation 2019/2072. The pathogen can be detected on its host plants using direct isolation, serological or PCR-based methods. Its identification is achieved using biochemical and nutritional assays, together with a multilocus sequence analysis based on seven housekeeping genes. The main pathway for the entry of the pathogen into the EU territory is plant propagation material. In the EU, there is large availability of host plants, with grapevine being one of the most important crops in Europe and more specifically in its Mediterranean areas. Since X. citri pv. viticola is only reported in tropical and subtropical areas (BSh and Aw climatic zones according to the Köppen-Geiger classification), there is uncertainty whether the climatic conditions in the EU territory are suitable for its establishment. Nevertheless, due to the great importance of grapevine for the EU agriculture, any disease outbreak may have a high-economic impact. Phytosanitary measures are available to prevent the introduction of the pathogen into the EU. X. citri pv. viticola satisfies the criteria that are within the remit of EFSA to assess for this species to be regarded as a potential Union quarantine pest.
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7
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Wu Y, Wang S, Nie W, Wang P, Fu L, Ahmad I, Zhu B, Chen G. A key antisense sRNA modulates the oxidative stress response and virulence in Xanthomonas oryzae pv. oryzicola. PLoS Pathog 2021; 17:e1009762. [PMID: 34297775 PMCID: PMC8336823 DOI: 10.1371/journal.ppat.1009762] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2021] [Revised: 08/04/2021] [Accepted: 06/27/2021] [Indexed: 11/18/2022] Open
Abstract
Pathogens integrate multiple environmental signals to navigate the host and control the expression of virulence genes. In this process, small regulatory noncoding RNAs (sRNAs) may function in gene expression as post-transcriptional regulators. In this study, the sRNA Xonc3711 functioned in the response of the rice pathogen, Xanthomonas oryzae pv. oryzicola (Xoc), to oxidative stress. Xonc3711 repressed production of the DNA-binding protein Xoc_3982 by binding to the xoc_3982 mRNA within the coding region. Mutational analysis showed that regulation required an antisense interaction between Xonc3711 and xoc_3982 mRNA, and RNase E was needed for degradation of the xoc_3982 transcript. Deletion of Xonc3711 resulted in a lower tolerance to oxidative stress due to the repression of flagella-associated genes and reduced biofilm formation. Furthermore, ChIP-seq and electrophoretic mobility shift assays showed that Xoc_3982 repressed the transcription of effector xopC2, which contributes to virulence in Xoc BLS256. This study describes how sRNA Xonc3711 modulates multiple traits in Xoc via signals perceived from the external environment. Small, stable RNA species perform diverse functions in both prokaryotes and eukaryotes. In this study, the sRNA Xonc3711 decreased the production of DNA-binding protein Xoc_3982 in the bacterium Xanthomonas oryzae pv. oryzicola (Xoc) by base pairing with the xoc_3982 transcript. When Xonc3711 was mutated, Xoc was impaired in its ability to form flagella and produce biofilms, which reduced Xoc tolerance to oxidative stress. We also discovered that the DNA-binding protein Xoc_3982 represses the expression of xopC2, which encodes an effector protein, and reduces its expression. Our results show that Xonc3711 modulates and integrates multiple systems in Xoc to protect cells from oxidative damage.
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Affiliation(s)
- Yan Wu
- Shanghai Yangtze River Delta Eco-Environmental Change and Management Observation and Research Station, Ministry of Science and Technology, Ministry of Education, Shanghai Urban Forest Ecosystem Research Station, National Forestry and Grassland Administration, Shanghai Cooperative Innovation Center for Modern Seed Industry, School of Agriculture and Biology, Shanghai Jiao Tong University, Shanghai, China
| | - Sai Wang
- Shanghai Yangtze River Delta Eco-Environmental Change and Management Observation and Research Station, Ministry of Science and Technology, Ministry of Education, Shanghai Urban Forest Ecosystem Research Station, National Forestry and Grassland Administration, Shanghai Cooperative Innovation Center for Modern Seed Industry, School of Agriculture and Biology, Shanghai Jiao Tong University, Shanghai, China
| | - Wenhan Nie
- Shanghai Yangtze River Delta Eco-Environmental Change and Management Observation and Research Station, Ministry of Science and Technology, Ministry of Education, Shanghai Urban Forest Ecosystem Research Station, National Forestry and Grassland Administration, Shanghai Cooperative Innovation Center for Modern Seed Industry, School of Agriculture and Biology, Shanghai Jiao Tong University, Shanghai, China
| | - Peihong Wang
- Shanghai Yangtze River Delta Eco-Environmental Change and Management Observation and Research Station, Ministry of Science and Technology, Ministry of Education, Shanghai Urban Forest Ecosystem Research Station, National Forestry and Grassland Administration, Shanghai Cooperative Innovation Center for Modern Seed Industry, School of Agriculture and Biology, Shanghai Jiao Tong University, Shanghai, China
| | - Luoyi Fu
- Shanghai Yangtze River Delta Eco-Environmental Change and Management Observation and Research Station, Ministry of Science and Technology, Ministry of Education, Shanghai Urban Forest Ecosystem Research Station, National Forestry and Grassland Administration, Shanghai Cooperative Innovation Center for Modern Seed Industry, School of Agriculture and Biology, Shanghai Jiao Tong University, Shanghai, China
| | - Iftikhar Ahmad
- Shanghai Yangtze River Delta Eco-Environmental Change and Management Observation and Research Station, Ministry of Science and Technology, Ministry of Education, Shanghai Urban Forest Ecosystem Research Station, National Forestry and Grassland Administration, Shanghai Cooperative Innovation Center for Modern Seed Industry, School of Agriculture and Biology, Shanghai Jiao Tong University, Shanghai, China
- Department of Environmental Sciences, COMSATS University Islamabad, Vehari Campus, Vehari, Pakistan
| | - Bo Zhu
- Shanghai Yangtze River Delta Eco-Environmental Change and Management Observation and Research Station, Ministry of Science and Technology, Ministry of Education, Shanghai Urban Forest Ecosystem Research Station, National Forestry and Grassland Administration, Shanghai Cooperative Innovation Center for Modern Seed Industry, School of Agriculture and Biology, Shanghai Jiao Tong University, Shanghai, China
- * E-mail: (BZ); (GC)
| | - Gongyou Chen
- Shanghai Yangtze River Delta Eco-Environmental Change and Management Observation and Research Station, Ministry of Science and Technology, Ministry of Education, Shanghai Urban Forest Ecosystem Research Station, National Forestry and Grassland Administration, Shanghai Cooperative Innovation Center for Modern Seed Industry, School of Agriculture and Biology, Shanghai Jiao Tong University, Shanghai, China
- * E-mail: (BZ); (GC)
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Catara V, Cubero J, Pothier JF, Bosis E, Bragard C, Đermić E, Holeva MC, Jacques MA, Petter F, Pruvost O, Robène I, Studholme DJ, Tavares F, Vicente JG, Koebnik R, Costa J. Trends in Molecular Diagnosis and Diversity Studies for Phytosanitary Regulated Xanthomonas. Microorganisms 2021; 9:862. [PMID: 33923763 PMCID: PMC8073235 DOI: 10.3390/microorganisms9040862] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2021] [Revised: 04/10/2021] [Accepted: 04/12/2021] [Indexed: 11/17/2022] Open
Abstract
Bacteria in the genus Xanthomonas infect a wide range of crops and wild plants, with most species responsible for plant diseases that have a global economic and environmental impact on the seed, plant, and food trade. Infections by Xanthomonas spp. cause a wide variety of non-specific symptoms, making their identification difficult. The coexistence of phylogenetically close strains, but drastically different in their phenotype, poses an added challenge to diagnosis. Data on future climate change scenarios predict an increase in the severity of epidemics and a geographical expansion of pathogens, increasing pressure on plant health services. In this context, the effectiveness of integrated disease management strategies strongly depends on the availability of rapid, sensitive, and specific diagnostic methods. The accumulation of genomic information in recent years has facilitated the identification of new DNA markers, a cornerstone for the development of more sensitive and specific methods. Nevertheless, the challenges that the taxonomic complexity of this genus represents in terms of diagnosis together with the fact that within the same bacterial species, groups of strains may interact with distinct host species demonstrate that there is still a long way to go. In this review, we describe and discuss the current molecular-based methods for the diagnosis and detection of regulated Xanthomonas, taxonomic and diversity studies in Xanthomonas and genomic approaches for molecular diagnosis.
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Affiliation(s)
- Vittoria Catara
- Department of Agriculture, Food and Environment, University of Catania, 95125 Catania, Italy
| | - Jaime Cubero
- National Institute for Agricultural and Food Research and Technology (INIA), 28002 Madrid, Spain;
| | - Joël F. Pothier
- Environmental Genomics and Systems Biology Research Group, Institute for Natural Resource Sciences, Zurich University of Applied Sciences (ZHAW), 8820 Wädenswil, Switzerland;
| | - Eran Bosis
- Department of Biotechnology Engineering, ORT Braude College of Engineering, Karmiel 2161002, Israel;
| | - Claude Bragard
- UCLouvain, Earth & Life Institute, Applied Microbiology, 1348 Louvain-la-Neuve, Belgium;
| | - Edyta Đermić
- Department of Plant Pathology, Faculty of Agriculture, University of Zagreb, 10000 Zagreb, Croatia;
| | - Maria C. Holeva
- Benaki Phytopathological Institute, Scientific Directorate of Phytopathology, Laboratory of Bacteriology, GR-14561 Kifissia, Greece;
| | - Marie-Agnès Jacques
- IRHS, INRA, AGROCAMPUS-Ouest, Univ Angers, SFR 4207 QUASAV, 49071 Beaucouzé, France;
| | - Francoise Petter
- European and Mediterranean Plant Protection Organization (EPPO/OEPP), 75011 Paris, France;
| | - Olivier Pruvost
- CIRAD, UMR PVBMT, F-97410 Saint Pierre, La Réunion, France; (O.P.); (I.R.)
| | - Isabelle Robène
- CIRAD, UMR PVBMT, F-97410 Saint Pierre, La Réunion, France; (O.P.); (I.R.)
| | | | - Fernando Tavares
- CIBIO—Centro de Investigação em Biodiversidade e Recursos Genéticos, InBIO-Laboratório Associado, Universidade do Porto, 4485-661 Vairão, Portugal; or
- FCUP-Faculdade de Ciências, Departamento de Biologia, Universidade do Porto, Rua do Campo Alegre, 4169-007 Porto, Portugal
| | | | - Ralf Koebnik
- Plant Health Institute of Montpellier (PHIM), Univ Montpellier, Cirad, INRAe, Institut Agro, IRD, 34398 Montpellier, France;
| | - Joana Costa
- Centre for Functional Ecology-Science for People & the Planet, Department of Life Sciences, University of Coimbra, 300-456 Coimbra, Portugal
- Laboratory for Phytopathology, Instituto Pedro Nunes, 3030-199 Coimbra, Portugal
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Zhang L, Zhang J, Wei Y, Hu W, Liu G, Zeng H, Shi H. Microbiome-wide association studies reveal correlations between the structure and metabolism of the rhizosphere microbiome and disease resistance in cassava. PLANT BIOTECHNOLOGY JOURNAL 2021; 19:689-701. [PMID: 33095967 PMCID: PMC8051613 DOI: 10.1111/pbi.13495] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/28/2020] [Accepted: 10/18/2020] [Indexed: 05/07/2023]
Abstract
Cassava is one of the most important staple food crops in tropical regions. To date, an understanding of the relationship between microbial communities and disease resistance in cassava has remained elusive. In order to explore the relationship among microbiome and phenotypes for further targeted design of microbial community, 16S rRNA and ITS of microbiome of ten cassava varieties were analysed, and a distinctive microbial community in the rhizosphere showed significant interdependence with disease resistance. Shotgun metagenome sequencing was performed to elucidate the structure of microbiomes of cassava rhizosphere. Comprehensive microbiome studies were performed to assess the correlation between the rhizosphere microbiome and disease resistance. Subsequently, the metagenome of rhizosphere microbiome was annotated to obtain taxonomic information at species level and identify metabolic pathways that were significantly associated with cassava disease resistance. Notably, cassava disease resistance was significantly associated with Lactococcus sp., which specifically produces nisin. To definitively explain the role of nisin and underlying mechanism, analysis of nisin biosynthesis-associated genes together with in vitro and in vivo experiments highlighted the effect of nisin on inhibiting the growth of Xanthomonas axonopodis pv. manihotis (Xam) and activating immune response in cassava. The new insights between cassava rhizosphere microbiome especially Lactococcus sp. and disease resistance provide valuable information into further control of cassava disease.
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Affiliation(s)
- Lin Zhang
- Hainan Key Laboratory for Sustainable Utilization of Tropical BioresourcesCollege of Tropical CropsCollege of Food Science and TechnologyCollege of Life and Pharmaceutical SciencesHainan UniversityHaikouChina
| | - Jiachao Zhang
- Hainan Key Laboratory for Sustainable Utilization of Tropical BioresourcesCollege of Tropical CropsCollege of Food Science and TechnologyCollege of Life and Pharmaceutical SciencesHainan UniversityHaikouChina
| | - Yunxie Wei
- Hainan Key Laboratory for Sustainable Utilization of Tropical BioresourcesCollege of Tropical CropsCollege of Food Science and TechnologyCollege of Life and Pharmaceutical SciencesHainan UniversityHaikouChina
| | - Wei Hu
- Key Laboratory of Biology and Genetic Resources of Tropical CropsInstitute of Tropical Bioscience and BiotechnologyChinese Academy of Tropical Agricultural SciencesHaikouChina
| | - Guoyin Liu
- Hainan Key Laboratory for Sustainable Utilization of Tropical BioresourcesCollege of Tropical CropsCollege of Food Science and TechnologyCollege of Life and Pharmaceutical SciencesHainan UniversityHaikouChina
| | - Hongqiu Zeng
- Hainan Key Laboratory for Sustainable Utilization of Tropical BioresourcesCollege of Tropical CropsCollege of Food Science and TechnologyCollege of Life and Pharmaceutical SciencesHainan UniversityHaikouChina
| | - Haitao Shi
- Hainan Key Laboratory for Sustainable Utilization of Tropical BioresourcesCollege of Tropical CropsCollege of Food Science and TechnologyCollege of Life and Pharmaceutical SciencesHainan UniversityHaikouChina
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10
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TAL Effector Repertoires of Strains of Xanthomonas phaseoli pv. manihotis in Commercial Cassava Crops Reveal High Diversity at the Country Scale. Microorganisms 2021; 9:microorganisms9020315. [PMID: 33557009 PMCID: PMC7913752 DOI: 10.3390/microorganisms9020315] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2020] [Revised: 12/17/2020] [Accepted: 12/24/2020] [Indexed: 12/13/2022] Open
Abstract
Transcription activator-like effectors (TALEs) play a significant role for pathogenesis in several xanthomonad pathosystems. Xanthomonas phaseoli pv. manihotis (Xpm), the causal agent of Cassava Bacterial Blight (CBB), uses TALEs to manipulate host metabolism. Information about Xpm TALEs and their target genes in cassava is scarce, but has been growing in the last few years. We aimed to characterize the TALE diversity in Colombian strains of Xpm and to screen for TALE-targeted gene candidates. We selected eighteen Xpm strains based on neutral genetic diversity at a country scale to depict the TALE diversity among isolates from cassava productive regions. RFLP analysis showed that Xpm strains carry TALomes with a bimodal size distribution, and affinity-based clustering of the sequenced TALEs condensed this variability mainly into five clusters. We report on the identification of 13 novel variants of TALEs in Xpm, as well as a functional variant with 22 repeats that activates the susceptibility gene MeSWEET10a, a previously reported target of TAL20Xam668. Transcriptomics and EBE prediction analyses resulted in the selection of several TALE-targeted candidate genes and two potential cases of functional convergence. This study provides new bases for assessing novel potential TALE targets in the Xpm–cassava interaction, which could be important factors that define the fate of the infection.
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Montenegro Benavides NA, Alvarez B A, Arrieta-Ortiz ML, Rodriguez-R LM, Botero D, Tabima JF, Castiblanco L, Trujillo C, Restrepo S, Bernal A. The type VI secretion system of Xanthomonas phaseoli pv. manihotis is involved in virulence and in vitro motility. BMC Microbiol 2021; 21:14. [PMID: 33407123 PMCID: PMC7788950 DOI: 10.1186/s12866-020-02066-1] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2020] [Accepted: 12/08/2020] [Indexed: 12/12/2022] Open
Abstract
Background The type VI protein secretion system (T6SS) is important in diverse cellular processes in Gram-negative bacteria, including interactions with other bacteria and with eukaryotic hosts. In this study we analyze the evolution of the T6SS in the genus Xanthomonas and evaluate its importance of the T6SS for virulence and in vitro motility in Xanthomonas phaseoli pv. manihotis (Xpm), the causal agent of bacterial blight in cassava (Manihot esculenta). We delineate the organization of the T6SS gene clusters in Xanthomonas and then characterize proteins of this secretion system in Xpm strain CIO151. Results We describe the presence of three different clusters in the genus Xanthomonas that vary in their organization and degree of synteny between species. Using a gene knockout strategy, we also found that vgrG and hcp are required for maximal aggressiveness of Xpm on cassava plants while clpV is important for both motility and maximal aggressiveness. Conclusion We characterized the T6SS in 15 different strains in Xanthomonas and our phylogenetic analyses suggest that the T6SS might have been acquired by a very ancient event of horizontal gene transfer and maintained through evolution, hinting at their importance for the adaptation of Xanthomonas to their hosts. Finally, we demonstrated that the T6SS of Xpm is functional, and significantly contributes to virulence and motility. This is the first experimental study that demonstrates the role of the T6SS in the Xpm-cassava interaction and the T6SS organization in the genus Xanthomonas. Supplementary Information The online version contains supplementary material available at 10.1186/s12866-020-02066-1.
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Affiliation(s)
| | - Alejandro Alvarez B
- Department of Biological Sciences, Universidad de los Andes, Bogotá, Colombia
| | | | - Luis Miguel Rodriguez-R
- Department of Microbiology and Digital Science Center (DiSC), University of Innsbruck, Innsbruck, Tyrol, Austria
| | - David Botero
- Department of Biological Sciences, Universidad de los Andes, Bogotá, Colombia
| | - Javier Felipe Tabima
- Botany and Plant Pathology Department, Oregon State University, Corvallis, OR, USA
| | - Luisa Castiblanco
- Department of Biological Sciences, Universidad de los Andes, Bogotá, Colombia
| | - Cesar Trujillo
- Department of Biological Sciences, Universidad de los Andes, Bogotá, Colombia
| | - Silvia Restrepo
- Department of Biological Sciences, Universidad de los Andes, Bogotá, Colombia
| | - Adriana Bernal
- Department of Biological Sciences, Universidad de los Andes, Bogotá, Colombia.
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Botero D, Monk J, Rodríguez Cubillos MJ, Rodríguez Cubillos A, Restrepo M, Bernal-Galeano V, Reyes A, González Barrios A, Palsson BØ, Restrepo S, Bernal A. Genome-Scale Metabolic Model of Xanthomonas phaseoli pv. manihotis: An Approach to Elucidate Pathogenicity at the Metabolic Level. Front Genet 2020; 11:837. [PMID: 32849823 PMCID: PMC7432306 DOI: 10.3389/fgene.2020.00837] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2019] [Accepted: 07/10/2020] [Indexed: 01/05/2023] Open
Abstract
Xanthomonas phaseoli pv. manihotis (Xpm) is the causal agent of cassava bacterial blight, the most important bacterial disease in this crop. There is a paucity of knowledge about the metabolism of Xanthomonas and its relevance in the pathogenic process, with the exception of the elucidation of the xanthan biosynthesis route. Here we report the reconstruction of the genome-scale model of Xpm metabolism and the insights it provides into plant-pathogen interactions. The model, iXpm1556, displayed 1,556 reactions, 1,527 compounds, and 890 genes. Metabolic maps of central amino acid and carbohydrate metabolism, as well as xanthan biosynthesis of Xpm, were reconstructed using Escher (https://escher.github.io/) to guide the curation process and for further analyses. The model was constrained using the RNA-seq data of a mutant of Xpm for quorum sensing (QS), and these data were used to construct context-specific models (CSMs) of the metabolism of the two strains (wild type and QS mutant). The CSMs and flux balance analysis were used to get insights into pathogenicity, xanthan biosynthesis, and QS mechanisms. Between the CSMs, 653 reactions were shared; unique reactions belong to purine, pyrimidine, and amino acid metabolism. Alternative objective functions were used to demonstrate a trade-off between xanthan biosynthesis and growth and the re-allocation of resources in the process of biosynthesis. Important features altered by QS included carbohydrate metabolism, NAD(P)+ balance, and fatty acid elongation. In this work, we modeled the xanthan biosynthesis and the QS process and their impact on the metabolism of the bacterium. This model will be useful for researchers studying host-pathogen interactions and will provide insights into the mechanisms of infection used by this and other Xanthomonas species.
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Affiliation(s)
- David Botero
- Laboratory of Mycology and Plant Pathology (LAMFU), Department of Chemical and Food Engineering, Universidad de Los Andes, Bogotá, Colombia
- Grupo de Diseño de Productos y Procesos (GDPP), Department of Chemical and Food Engineering, Universidad de Los Andes, Bogotá, Colombia
- Max Planck Tandem Group in Computational Biology, Universidad de Los Andes, Bogotá, Colombia
- Grupo de Biología Computacional y Ecología Microbiana, Department of Biological Sciences, Universidad de Los Andes, Bogotá, Colombia
| | - Jonathan Monk
- Systems Biology Research Group, Department of Bioengineering, University of California, San Diego, San Diego, CA, United States
| | - María Juliana Rodríguez Cubillos
- Laboratory of Mycology and Plant Pathology (LAMFU), Department of Chemical and Food Engineering, Universidad de Los Andes, Bogotá, Colombia
- Grupo de Diseño de Productos y Procesos (GDPP), Department of Chemical and Food Engineering, Universidad de Los Andes, Bogotá, Colombia
| | | | - Mariana Restrepo
- Laboratory of Mycology and Plant Pathology (LAMFU), Department of Chemical and Food Engineering, Universidad de Los Andes, Bogotá, Colombia
| | - Vivian Bernal-Galeano
- Laboratory of Mycology and Plant Pathology (LAMFU), Department of Chemical and Food Engineering, Universidad de Los Andes, Bogotá, Colombia
| | - Alejandro Reyes
- Max Planck Tandem Group in Computational Biology, Universidad de Los Andes, Bogotá, Colombia
- Grupo de Biología Computacional y Ecología Microbiana, Department of Biological Sciences, Universidad de Los Andes, Bogotá, Colombia
| | - Andrés González Barrios
- Grupo de Diseño de Productos y Procesos (GDPP), Department of Chemical and Food Engineering, Universidad de Los Andes, Bogotá, Colombia
| | - Bernhard Ø. Palsson
- Systems Biology Research Group, Department of Bioengineering, University of California, San Diego, San Diego, CA, United States
| | - Silvia Restrepo
- Laboratory of Mycology and Plant Pathology (LAMFU), Department of Chemical and Food Engineering, Universidad de Los Andes, Bogotá, Colombia
| | - Adriana Bernal
- Laboratory of Molecular Interactions of Agricultural Microbes, LIMMA, Department of Biological Sciences, Universidad de Los Andes, Bogotá, Colombia
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Rache L, Blondin L, Flores C, Trujillo C, Szurek B, Restrepo S, Koebnik R, Bernal A, Vernière C. An Optimized Microsatellite Scheme for Assessing Populations of Xanthomonas phaseoli pv. manihotis. PHYTOPATHOLOGY 2019; 109:859-869. [PMID: 30908143 DOI: 10.1094/phyto-06-18-0210-r] [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: 06/09/2023]
Abstract
Diverse molecular markers have been used to analyze the genetic diversity of plant pathogens. Compared with traditional fingerprinting methods, multiple loci variable number of tandem repeat analyses (MLVAs) have gained importance recently due to their reproducibility, high discriminatory power, ease of performance, low cost, and throughput potential. These characteristics are desirable for continuous pathogen monitoring, especially for pathogens with relatively low genetic diversity, and for disease epidemiology studies. Genetic diversity studies of Xanthomonas phaseoli pv. manihotis, which is the causal agent of cassava bacterial blight, have shown variability and changes in the bacterial population over time. Thus, an easy and fast method needs to be developed to type populations of this pathogen in different countries of the world, especially on small scales. In this study, we developed an MLVA scheme to analyze X. phaseoli pv. manihotis variability on a local scale. The MLVA-15 scheme comprises 15 variable number of tandem repeat loci grouped into four multiplex polymerase chain reaction pools. We showed that the MLVA-15 scheme had slightly higher discriminatory ability at the locality level when compared with amplified fragment length polymorphisms. The MLVA-15 scheme allowed for an accurate determination of the number of genotypes in the sample and showed reproducibility and portability. Additionally, this scheme could be used to analyze numerous strains in a reasonable timeframe. The MLVA-15 scheme was highly specific to X. phaseoli but up to eight tandem repeat loci could be amplified from other Xanthomonas spp. Finally, we assessed the utility of the scheme for analyses of X. phaseoli pv. manihotis genetic variability in the Colombian Caribbean region. MLVA-15 distinguished 88.9% of the haplotypes in our sample. Strains originating from the same field and isolated at the same time could be discriminated. In this study, the advantages of the MLVA-15 scheme targeting 6- or 7-bp repeats were demonstrated. Moreover, this scheme was a fast method that was appropriate for routine monitoring of X. phaseoli pv. manihotis populations on a local scale and, thus, was useful for addressing epidemiological questions.
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Affiliation(s)
- Leidy Rache
- 1 Laboratorio de Interacciones Moleculares de Microorganismos Agrícolas (LIMMA), Universidad de los Andes, Bogotá D.C., Colombia
- 2 Laboratorio de Micología y Fitopatología (LAMFU), Universidad de los Andes, Bogotá D.C., Colombia
| | | | - Carolina Flores
- 4 IRD, Cirad, Université de Montpellier, IPME, Montpellier, France
| | - Cesar Trujillo
- 1 Laboratorio de Interacciones Moleculares de Microorganismos Agrícolas (LIMMA), Universidad de los Andes, Bogotá D.C., Colombia
- 2 Laboratorio de Micología y Fitopatología (LAMFU), Universidad de los Andes, Bogotá D.C., Colombia
- 5 Affiliated until 2015
| | - Boris Szurek
- 4 IRD, Cirad, Université de Montpellier, IPME, Montpellier, France
| | - Silvia Restrepo
- 2 Laboratorio de Micología y Fitopatología (LAMFU), Universidad de los Andes, Bogotá D.C., Colombia
| | - Ralf Koebnik
- 4 IRD, Cirad, Université de Montpellier, IPME, Montpellier, France
| | - Adriana Bernal
- 1 Laboratorio de Interacciones Moleculares de Microorganismos Agrícolas (LIMMA), Universidad de los Andes, Bogotá D.C., Colombia
- 2 Laboratorio de Micología y Fitopatología (LAMFU), Universidad de los Andes, Bogotá D.C., Colombia
| | - Christian Vernière
- 6 Cirad, UMR BGPI, F-34398 Montpellier, France; and
- 7 BGPI, Université de Montpellier, Cirad, INRA, Montpellier SupAgro, Montpellier, France
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Ferreira MASV, Bonneau S, Briand M, Cesbron S, Portier P, Darrasse A, Gama MAS, Barbosa MAG, Mariano RDLR, Souza EB, Jacques MA. Xanthomonas citri pv. viticola Affecting Grapevine in Brazil: Emergence of a Successful Monomorphic Pathogen. FRONTIERS IN PLANT SCIENCE 2019; 10:489. [PMID: 31057588 PMCID: PMC6482255 DOI: 10.3389/fpls.2019.00489] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 11/29/2018] [Accepted: 03/29/2019] [Indexed: 06/09/2023]
Abstract
The pathovar viticola of Xanthomonas citri causes bacterial canker of grapevine. This disease was first recorded in India in 1972, and later in Brazil in 1998, where its distribution is currently restricted to the northeastern region. A multilocus sequence analysis (MLSA) based on seven housekeeping genes and a multilocus variable number of tandem repeat analysis (MLVA) with eight loci were performed in order to assess the genetic relatedness among strains from India and Brazil. Strains isolated in India from three related pathovars affecting Vitaceae species and pathogenic strains isolated from Amaranthus sp. found in bacterial canker-infected vineyards in Brazil were also included. MLSA revealed lack of diversity in all seven genes and grouped grapevine and Amaranthus strains in a monophyletic group in X. citri. The VNTR (variable number of tandem repeat) typing scheme conducted on 107 strains detected 101 haplotypes. The total number of alleles per locus ranged from 5 to 12. A minimum spanning tree (MST) showed that Brazilian strains were clearly separated from Indian strains, which showed unique alleles at three loci. The two strains isolated from symptomatic Amaranthus sp. presented unique alleles at two loci. STRUCTURE analyses revealed three groups congruent with MST and a fourth group with strains from India and Brazil. Admixture among populations were observed in all groups. MST, STRUCTURE and e-BURST analyses showed that the strains collected in 1998 belong to two distinct groups, with predicted founder genotypes from two different vineyards in the same region. This suggest that one introduction of grape planting materials contaminated with genetically distinct strains took place, which was followed by pathogen adaptation. Genome sequencing of one Brazilian strain confirmed typical attributes of pathogenic xanthomonads and allowed the design of a complementary VNTR typing scheme dedicated to X. citri pv. viticola that will allow further epidemiological survey of this genetically monomorphic pathovar.
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Affiliation(s)
| | - Sophie Bonneau
- IRHS, INRA, AGROCAMPUS-Ouest, SFR4207 QUASAV, Université d’Angers, Beaucouzé, France
| | - Martial Briand
- IRHS, INRA, AGROCAMPUS-Ouest, SFR4207 QUASAV, Université d’Angers, Beaucouzé, France
| | - Sophie Cesbron
- IRHS, INRA, AGROCAMPUS-Ouest, SFR4207 QUASAV, Université d’Angers, Beaucouzé, France
| | - Perrine Portier
- IRHS, INRA, AGROCAMPUS-Ouest, SFR4207 QUASAV, Université d’Angers, Beaucouzé, France
| | - Armelle Darrasse
- IRHS, INRA, AGROCAMPUS-Ouest, SFR4207 QUASAV, Université d’Angers, Beaucouzé, France
| | - Marco A. S. Gama
- Laboratório de Fitobacteriologia, Departamento de Agronomia, Universidade Federal Rural de Pernambuco, Recife, Brazil
| | | | - Rosa de L. R. Mariano
- Laboratório de Fitobacteriologia, Departamento de Agronomia, Universidade Federal Rural de Pernambuco, Recife, Brazil
| | - Elineide B. Souza
- Laboratório de Fitobacteriologia, Departamento de Agronomia, Universidade Federal Rural de Pernambuco, Recife, Brazil
| | - Marie-Agnès Jacques
- IRHS, INRA, AGROCAMPUS-Ouest, SFR4207 QUASAV, Université d’Angers, Beaucouzé, France
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Islam W, Qasim M, Noman A, Adnan M, Tayyab M, Farooq TH, Wei H, Wang L. Plant microRNAs: Front line players against invading pathogens. Microb Pathog 2018. [PMID: 29524548 DOI: 10.1016/j.micpath.2018.03.008] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Plants are attacked by a large number of pathogens. To defend against these pathogens, plants activate or repress a vast array of genes. For genetic expression and reprogramming, host endogenous small RNAs (sRNAs) are the key factors. Among these sRNAs, microRNAs (miRNAs) mediate gene regulation through RNA silencing at the post-transcriptional level and play an essential role in the defense responses to biotic and abiotic stress. In the recent years, high-throughput sequencing has enabled the researchers to uncover the role of plant miRNAs during pathogen invasion. So here we have reviewed the recent research findings illustrating the plant miRNAs active involvement in various defense processes during fungal, bacterial, viral and nematode infections. However, rapid validation of direct targets of miRNAs is the dire need of time, which can be very helpful in improving the plant resistance against various pathogenic diseases.
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Affiliation(s)
- Waqar Islam
- College of Plant Protection, Fujian Agriculture and Forestry University, Fuzhou, 350002, China; Govt. of Punjab, Agriculture Department, Lahore, Pakistan.
| | - Muhammad Qasim
- College of Plant Protection, Fujian Agriculture and Forestry University, Fuzhou, 350002, China; State Key Laboratory of Ecological Pest Control for Fujian and Taiwan Crops, Fujian Agriculture and Forestry University, Fuzhou, 350002, China; Key Laboratory of Integrated Pest Management for Fujian-Taiwan Crops, Ministry of Agriculture, Fuzhou, 350002, China
| | - Ali Noman
- College of Crop Sciences, Fujian Agriculture and Forestry University, Fuzhou, 350002, China; Department of Botany, Govt. College University, Faisalabad, Pakistan
| | - Muhammad Adnan
- College of Plant Protection, Fujian Agriculture and Forestry University, Fuzhou, 350002, China; State Key Laboratory of Ecological Pest Control for Fujian and Taiwan Crops, Fujian Agriculture and Forestry University, Fuzhou, 350002, China
| | - Muhammad Tayyab
- College of Crop Sciences, Fujian Agriculture and Forestry University, Fuzhou, 350002, China
| | - Taimoor Hassan Farooq
- College of Forestry, Fujian Agriculture and Forestry University, Fuzhou, 350002, China
| | - Huang Wei
- College of Plant Protection, Fujian Agriculture and Forestry University, Fuzhou, 350002, China
| | - Liande Wang
- College of Plant Protection, Fujian Agriculture and Forestry University, Fuzhou, 350002, China; State Key Laboratory of Ecological Pest Control for Fujian and Taiwan Crops, Fujian Agriculture and Forestry University, Fuzhou, 350002, China; Key Laboratory of Integrated Pest Management for Fujian-Taiwan Crops, Ministry of Agriculture, Fuzhou, 350002, China.
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Medina CA, Reyes PA, Trujillo CA, Gonzalez JL, Bejarano DA, Montenegro NA, Jacobs JM, Joe A, Restrepo S, Alfano JR, Bernal A. The role of type III effectors from Xanthomonas axonopodis pv. manihotis in virulence and suppression of plant immunity. MOLECULAR PLANT PATHOLOGY 2018; 19:593-606. [PMID: 28218447 PMCID: PMC6638086 DOI: 10.1111/mpp.12545] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/20/2016] [Revised: 01/25/2017] [Accepted: 02/15/2017] [Indexed: 05/29/2023]
Abstract
Xanthomonas axonopodis pv. manihotis (Xam) causes cassava bacterial blight, the most important bacterial disease of cassava. Xam, like other Xanthomonas species, requires type III effectors (T3Es) for maximal virulence. Xam strain CIO151 possesses 17 predicted T3Es belonging to the Xanthomonas outer protein (Xop) class. This work aimed to characterize nine Xop effectors present in Xam CIO151 for their role in virulence and modulation of plant immunity. Our findings demonstrate the importance of XopZ, XopX, XopAO1 and AvrBs2 for full virulence, as well as a redundant function in virulence between XopN and XopQ in susceptible cassava plants. We tested their role in pathogen-associated molecular pattern (PAMP)-triggered immunity (PTI) and effector-triggered immunity (ETI) using heterologous systems. AvrBs2, XopR and XopAO1 are capable of suppressing PTI. ETI suppression activity was only detected for XopE4 and XopAO1. These results demonstrate the overall importance and diversity in functions of major virulence effectors AvrBs2 and XopAO1 in Xam during cassava infection.
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Affiliation(s)
- Cesar Augusto Medina
- Universidad de los Andes, Laboratorio de Micología y Fitopatología de la Universidad de los Andes111711 BogotáColombia
| | - Paola Andrea Reyes
- Universidad de los Andes, Laboratorio de Micología y Fitopatología de la Universidad de los Andes111711 BogotáColombia
| | - Cesar Augusto Trujillo
- Universidad de los Andes, Laboratorio de Micología y Fitopatología de la Universidad de los Andes111711 BogotáColombia
| | - Juan Luis Gonzalez
- Universidad de los Andes, Laboratorio de Micología y Fitopatología de la Universidad de los Andes111711 BogotáColombia
| | - David Alejandro Bejarano
- Universidad de los Andes, Laboratorio de Micología y Fitopatología de la Universidad de los Andes111711 BogotáColombia
| | - Nathaly Andrea Montenegro
- Universidad de los Andes, Laboratorio de Micología y Fitopatología de la Universidad de los Andes111711 BogotáColombia
| | - Jonathan M. Jacobs
- Institut de Recherche pour le De´veloppement (IRD), CiradUniversite´ Montpellier, Interactions Plantes Microorganismes Environnement (IPME), 34394MontpellierFrance
| | - Anna Joe
- Center for Plant Science InnovationUniversity of NebraskaLincolnNE68588‐0660USA
- Department of Plant PathologyUniversity of NebraskaLincolnNE68588‐0722USA
- Present address:
Department of Plant Pathology and the Genome CenterUniversity of California, Davis, CA 95616, USA, and Joint BioEnergy Institute and Physical Biosciences Division, Lawrence Berkeley National LaboratoryBerkeleyCA94720USA
| | - Silvia Restrepo
- Universidad de los Andes, Laboratorio de Micología y Fitopatología de la Universidad de los Andes111711 BogotáColombia
| | - James R. Alfano
- Center for Plant Science InnovationUniversity of NebraskaLincolnNE68588‐0660USA
- Department of Plant PathologyUniversity of NebraskaLincolnNE68588‐0722USA
| | - Adriana Bernal
- Universidad de los Andes, Laboratorio de Micología y Fitopatología de la Universidad de los Andes111711 BogotáColombia
- Present address:
Novozymes, Inc., DavisCA95618USA
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McCallum EJ, Anjanappa RB, Gruissem W. Tackling agriculturally relevant diseases in the staple crop cassava (Manihot esculenta). CURRENT OPINION IN PLANT BIOLOGY 2017; 38:50-58. [PMID: 28477536 DOI: 10.1016/j.pbi.2017.04.008] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/28/2017] [Revised: 04/02/2017] [Accepted: 04/10/2017] [Indexed: 06/07/2023]
Abstract
Cassava is an important staple food crop for millions of people in tropical regions across Africa, South America and Asia. Viral, bacterial and fungal diseases impact cassava yield in all three regions. The viruses causing cassava mosaic disease and cassava brown streak disease have been particularly devastating to cassava production in Africa. Improved farming practices and disease monitoring can reduce the impact of cassava diseases in the field. The availability of disease resistant cassava varieties developed through breeding or genetic engineering is key to tackling disease incidence and severity.
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Affiliation(s)
- Emily J McCallum
- Department of Biology, Plant Biotechnology, ETH Zurich, CH-8092 Zurich, Switzerland
| | - Ravi B Anjanappa
- Department of Biology, Plant Biotechnology, ETH Zurich, CH-8092 Zurich, Switzerland
| | - Wilhelm Gruissem
- Department of Biology, Plant Biotechnology, ETH Zurich, CH-8092 Zurich, Switzerland.
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New Multilocus Variable-Number Tandem-Repeat Analysis (MLVA) Scheme for Fine-Scale Monitoring and Microevolution-Related Study of Ralstonia pseudosolanacearum Phylotype I Populations. Appl Environ Microbiol 2017; 83:AEM.03095-16. [PMID: 28003195 DOI: 10.1128/aem.03095-16] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2016] [Accepted: 12/13/2016] [Indexed: 12/31/2022] Open
Abstract
Bacterial wilt caused by the Ralstonia solanacearum species complex (RSSC) is considered one of the most harmful plant diseases in the world. Special attention should be paid to R. pseudosolanacearum phylotype I due to its large host range, its worldwide distribution, and its high evolutionary potential. So far, the molecular epidemiology and population genetics of this bacterium are poorly understood. Until now, the genetic structure of the RSSC has been analyzed on the worldwide and regional scales. Emerging questions regarding evolutionary forces in RSSC adaptation to hosts now require genetic markers that are able to monitor RSSC field populations. In this study, we aimed to evaluate the multilocus variable-number tandem-repeat analysis (MLVA) approach for its ability to discriminate genetically close phylotype I strains and for population genetics studies. We developed a new MLVA scheme (MLVA-7) allowing us to genotype 580 R. pseudosolanacearum phylotype I strains extracted from susceptible and resistant hosts and from different habitats (stem, soil, and rhizosphere). Based on specificity, polymorphism, and the amplification success rate, we selected seven fast-evolving variable-number tandem-repeat (VNTR) markers. The newly developed MLVA-7 scheme showed higher discriminatory power than the previously published MLVA-13 scheme when applied to collections sampled from the same location on different dates and to collections from different locations on very small scales. Our study provides a valuable tool for fine-scale monitoring and microevolution-related study of R. pseudosolanacearum phylotype I populations.IMPORTANCE Understanding the evolutionary dynamics of adaptation of plant pathogens to new hosts or ecological niches has become a key point for the development of innovative disease management strategies, including durable resistance. Whereas the molecular mechanisms underlying virulence or pathogenicity changes have been studied thoroughly, the population genetics of plant pathogen adaptation remains an open, unexplored field, especially for plant-pathogenic bacteria. MLVA has become increasingly popular for epidemiosurveillance and molecular epidemiology studies of plant pathogens. However, this method has been used mostly for genotyping and identification on a regional or global scale. In this study, we developed a new MLVA scheme, targeting phylotype I of the soilborne Ralstonia solanacearum species complex (RSSC), specifically to address the bacterial population genetics on the field scale. Such a MLVA scheme, based on fast-evolving loci, may be a tool of choice for field experimental evolution and spatial genetics studies.
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Mutka AM, Fentress SJ, Sher JW, Berry JC, Pretz C, Nusinow DA, Bart R. Quantitative, Image-Based Phenotyping Methods Provide Insight into Spatial and Temporal Dimensions of Plant Disease. PLANT PHYSIOLOGY 2016; 172:650-660. [PMID: 27443602 PMCID: PMC5047107 DOI: 10.1104/pp.16.00984] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/20/2016] [Accepted: 07/19/2016] [Indexed: 05/25/2023]
Abstract
Plant disease symptoms exhibit complex spatial and temporal patterns that are challenging to quantify. Image-based phenotyping approaches enable multidimensional characterization of host-microbe interactions and are well suited to capture spatial and temporal data that are key to understanding disease progression. We applied image-based methods to investigate cassava bacterial blight, which is caused by the pathogen Xanthomonas axonopodis pv. manihotis (Xam). We generated Xam strains in which individual predicted type III effector (T3E) genes were mutated and applied multiple imaging approaches to investigate the role of these proteins in bacterial virulence. Specifically, we quantified bacterial populations, water-soaking disease symptoms, and pathogen spread from the site of inoculation over time for strains with mutations in avrBs2, xopX, and xopK as compared to wild-type Xam ∆avrBs2 and ∆xopX both showed reduced growth in planta and delayed spread through the vasculature system of cassava. ∆avrBs2 exhibited reduced water-soaking symptoms at the site of inoculation. In contrast, ∆xopK exhibited enhanced induction of disease symptoms at the site of inoculation but reduced spread through the vasculature. Our results highlight the importance of adopting a multipronged approach to plant disease phenotyping to more fully understand the roles of T3Es in virulence. Finally, we demonstrate that the approaches used in this study can be extended to many host-microbe systems and increase the dimensions of phenotype that can be explored.
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Affiliation(s)
- Andrew M Mutka
- Donald Danforth Plant Science Center, Saint Louis, MO 63132
| | | | - Joel W Sher
- Donald Danforth Plant Science Center, Saint Louis, MO 63132
| | | | - Chelsea Pretz
- Donald Danforth Plant Science Center, Saint Louis, MO 63132
| | | | - Rebecca Bart
- Donald Danforth Plant Science Center, Saint Louis, MO 63132
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20
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López-Soriano P, Boyer K, Cesbron S, Morente MC, Peñalver J, Palacio-Bielsa A, Vernière C, López MM, Pruvost O. Multilocus Variable Number of Tandem Repeat Analysis Reveals Multiple Introductions in Spain of Xanthomonas arboricola pv. pruni, the Causal Agent of Bacterial Spot Disease of Stone Fruits and Almond. PLoS One 2016; 11:e0163729. [PMID: 27669415 PMCID: PMC5036818 DOI: 10.1371/journal.pone.0163729] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2016] [Accepted: 09/13/2016] [Indexed: 12/05/2022] Open
Abstract
Xanthomonas arboricola pv. pruni is the causal agent of the bacterial spot disease of stone fruits, almond and some ornamental Prunus species. In Spain it was first detected in 2002 and since then, several outbreaks have occurred in different regions affecting mainly Japanese plum, peach and almond, both in commercial orchards and nurseries. As the origin of the introduction(s) was unknown, we have assessed the genetic diversity of 239 X. arboricola pv. pruni strains collected from 11 Spanish provinces from 2002 to 2013 and 25 reference strains from international collections. We have developed an optimized multilocus variable number of tandem repeat analysis (MLVA) scheme targeting 18 microsatellites and five minisatellites. A high discriminatory power was achieved since almost 50% of the Spanish strains were distinguishable, confirming the usefulness of this genotyping technique at small spatio-temporal scales. Spanish strains grouped in 18 genetic clusters (conservatively delineated so that each cluster contained haplotype networks linked by up to quadruple-locus variations). Furthermore, pairwise comparisons among populations from different provinces showed a strong genetic differentiation. Our results suggest multiple introductions of this pathogen in Spain and redistribution through contaminated nursery propagative plant material.
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Affiliation(s)
| | - Karine Boyer
- UMR Peuplement Végétaux et Bioagresseurs en Milieu Tropical, Centre de Coopération Internationale en Recherche Agronomique pour le Développement, Saint-Pierre, La Réunion, France
| | - Sophie Cesbron
- INRA, UMR1345 IRHS Institut de Recherche en Horticulture et Semences, Beaucouzé, France
| | | | - Javier Peñalver
- Instituto Valenciano de Investigaciones Agrarias, Moncada, Valencia, Spain
| | - Ana Palacio-Bielsa
- Centro de Investigación y Tecnología Agroalimentaria de Aragón. Instituto Agroalimentario de Aragón, IA2 (CITA-Universidad de Zaragoza), Zaragoza, Spain
| | - Christian Vernière
- UMR Peuplement Végétaux et Bioagresseurs en Milieu Tropical, Centre de Coopération Internationale en Recherche Agronomique pour le Développement, Saint-Pierre, La Réunion, France
- UMR Biologie et Génétique des Interactions Plante-Parasite, Centre de Coopération Internationale en Recherche Agronomique pour le Développement, Montpellier, France
| | - María M. López
- Instituto Valenciano de Investigaciones Agrarias, Moncada, Valencia, Spain
- * E-mail:
| | - Olivier Pruvost
- UMR Peuplement Végétaux et Bioagresseurs en Milieu Tropical, Centre de Coopération Internationale en Recherche Agronomique pour le Développement, Saint-Pierre, La Réunion, France
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21
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Cohn M, Morbitzer R, Lahaye T, Staskawicz BJ. Comparison of gene activation by two TAL effectors from Xanthomonas axonopodis pv. manihotis reveals candidate host susceptibility genes in cassava. MOLECULAR PLANT PATHOLOGY 2016; 17:875-89. [PMID: 26575863 PMCID: PMC6638523 DOI: 10.1111/mpp.12337] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/12/2015] [Revised: 09/23/2015] [Accepted: 10/13/2015] [Indexed: 05/10/2023]
Abstract
Xanthomonas axonopodis pv. manihotis (Xam) employs transcription activator-like (TAL) effectors to promote bacterial growth and symptom formation during infection of cassava. TAL effectors are secreted via the bacterial type III secretion system into plant cells, where they are directed to the nucleus, bind DNA in plant promoters and activate the expression of downstream genes. The DNA-binding activity of TAL effectors is carried out by a central domain which contains a series of repeat variable diresidues (RVDs) that dictate the sequence of bound nucleotides. TAL14Xam668 promotes virulence in Xam strain Xam668 and has been shown to activate multiple cassava genes. In this study, we used RNA sequencing to identify the full target repertoire of TAL14Xam668 in cassava, which includes over 50 genes. A subset of highly up-regulated genes was tested for activation by TAL14CIO151 from Xam strain CIO151. Although TAL14CIO151 and TAL14Xam668 differ by only a single RVD, they display differential activation of gene targets. TAL14CIO151 complements the TAL14Xam668 mutant defect, implying that shared target genes are important for TAL14Xam668 -mediated disease susceptibility. Complementation with closely related TAL effectors is a novel approach to the narrowing down of biologically relevant susceptibility genes of TAL effectors with multiple targets. This study provides an example of how TAL effector target activation by two strains within a single species of Xanthomonas can be dramatically affected by a small change in RVD-nucleotide affinity at a single site, and reflects the parameters of RVD-nucleotide interaction determined using designer TAL effectors in transient systems.
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Affiliation(s)
- Megan Cohn
- Department of Plant and Microbial Biology, University of California, Berkeley, CA, 94720-3120, USA
| | - Robert Morbitzer
- Department of General Genetics, Center of Plant Molecular Biology (ZMBP) University of Tübingen, D-72076, Tübingen, Germany
| | - Thomas Lahaye
- Department of General Genetics, Center of Plant Molecular Biology (ZMBP) University of Tübingen, D-72076, Tübingen, Germany
| | - Brian J Staskawicz
- Department of Plant and Microbial Biology, University of California, Berkeley, CA, 94720-3120, USA
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22
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Díaz Tatis P, Zárate CA, Bernal Giraldo A, López Carrascal C. Infección de callo embriogénico friable de yuca con Xanthomonas axonopodis pv. manihotis (Xam). REVISTA COLOMBIANA DE BIOTECNOLOGÍA 2016. [DOI: 10.15446/rev.colomb.biote.v18n2.61523] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
Abstract
Las nuevas tecnologías para la edición de genomas, como los TALEN y el sistema CRISPR/Cas9, representan una gran oportunidad para mejorar características deseables en diferentes organismos. Los TALEN son el resultado del acoplamiento de nucleasas a los TALE (Transcription Activator-Like Effectors), los cuales son efectores naturales de gran importancia en la patogénesis de las especies de Xanthomonas. Xanthomonas axonopodis pv. manihotis (Xam) es el agente causal del añublo bacteriano de la yuca, quien durante el proceso patogénico es capaz de translocar sus efectores a la célula vegetal mediante el sistema de secreción tipo tres (SSTT). Actualmente no hay protocolos estándar para la edición de genomas en yuca. En este estudio se exploró la posibilidad de translocar efectores sobre callo embriogénico friable (CEF) a través de la inoculación con Xam, con el fin de determinar el potencial de este patógeno como sistema de entrega de TALEN. El CEF de dos variedades de yuca susceptibles (COL2215 y cv. 60444) se cocultivaron con la cepa Xam668 a diferentes tiempos. Posteriormente, se evaluó la expresión de marcadores correspondientes a los genes blanco conocidos para los TALE presentes en esta cepa bacteriana. Aunque no se logró demostrar la translocación de los mismos en el tejido embriogénico, sí se lograron establecer condiciones adecuadas de cocultivo con Xam y el efecto que la infección bacteriana tiene sobre la regeneración de embriones a partir de este tejido. Palabras clave: cultivo de tejidos vegetales, edición de genomas, sistema de secreción tipo tres, efectores TALE, transformación.
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23
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Torondel B, Ensink JHJ, Gundogdu O, Ijaz UZ, Parkhill J, Abdelahi F, Nguyen VA, Sudgen S, Gibson W, Walker AW, Quince C. Assessment of the influence of intrinsic environmental and geographical factors on the bacterial ecology of pit latrines. Microb Biotechnol 2016; 9:209-23. [PMID: 26875588 PMCID: PMC4767293 DOI: 10.1111/1751-7915.12334] [Citation(s) in RCA: 45] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2015] [Revised: 10/02/2015] [Accepted: 10/12/2015] [Indexed: 12/15/2022] Open
Abstract
Improving the rate and extent of faecal decomposition in basic forms of sanitation such as pit latrines would benefit around 1.7 billion users worldwide, but to do so requires a major advance in our understanding of the biology of these systems. As a critical first step, bacterial diversity and composition was studied in 30 latrines in Tanzania and Vietnam using pyrosequencing of 16S rRNA genes, and correlated with a number of intrinsic environmental factors such as pH, temperature, organic matter content/composition and geographical factors. Clear differences were observed at the operational taxonomic unit, family and phylum level in terms of richness and community composition between latrines in Tanzania and Vietnam. The results also clearly show that environmental variables, particularly substrate type and availability, can exert a strong structuring influence on bacterial communities in latrines from both countries. The origins and significance of these environmental differences are discussed. This work describes the bacterial ecology of pit latrines in combination with inherent latrine characteristics at an unprecedented level of detail. As such, it provides useful baseline information for future studies that aim to understand the factors that affect decomposition rates in pit latrines.
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Affiliation(s)
- Belen Torondel
- Environmental Health Group, Department of Disease Control, London School of Hygiene and Tropical Medicine, Keppel Street, London, WC1E 7HT, UK
| | - Jeroen H J Ensink
- Environmental Health Group, Department of Disease Control, London School of Hygiene and Tropical Medicine, Keppel Street, London, WC1E 7HT, UK
| | - Ozan Gundogdu
- Pathogen Molecular Biology Department, Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, Keppel Street, London, WC1E 7HT, UK
| | | | - Julian Parkhill
- Pathogen Genomics Group, Wellcome Trust Sanger Institute, Wellcome Trust Genome Campus, Hinxton, CB10 1SA, UK
| | - Faraji Abdelahi
- Ifakara Health Institute, off Mlabani Passage, P.O. Box 53, Ifakara, Tanzania
| | - Viet-Anh Nguyen
- Hanoi University of Civil Engineering, 55 Giai Phong Road, Hanoi, Vietnam
| | - Steven Sudgen
- Environmental Health Group, Department of Disease Control, London School of Hygiene and Tropical Medicine, Keppel Street, London, WC1E 7HT, UK
| | - Walter Gibson
- Bear Valley Ventures, Braeside, Utkinton Lane, Cotebrook, Tarporley, Cheshire CW6 0JH, UK
| | - Alan W Walker
- Pathogen Genomics Group, Wellcome Trust Sanger Institute, Wellcome Trust Genome Campus, Hinxton, CB10 1SA, UK.,Microbiology Group, Rowett Institute of Nutrition and Health, University of Aberdeen, Aberdeen, AB21 9SB, UK
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24
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Muñoz Bodnar A, Cruz Gómez LM, Bernal A, Szurek B, López Carrascal CE. COMPARING INOCULATION METHODS TO EVALUATE THE GROWTH OF Xanthomonas axonopodis pv. manihotis ON CASSAVA PLANTS. ACTA BIOLÓGICA COLOMBIANA 2014. [DOI: 10.15446/abc.v20n2.43130] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
Abstract
<p class="ecxmsonormal"><em>Xanthomonas axonopodis </em>pv. manihotis (<em>Xam</em>) is the causal agent of cassava bacterial blight (CBB), a major disease for cassava crops in South America and Africa. Until now the development of the disease is measured via AUDPC (Area Under Disease Progress Curve) but no reliable quantitative methods are available probably due to high variability of bacterial growth <em>in planta</em>. To establish an accurate method for bacterial quantification during the course of <em>Xam</em> infection within the host tissues, we analyzed bacterial populations upon stem and leaf-puncturing as well as leaf-clipping of cassava varieties MCOL1522 and SG107-35 challenged with the virulent <em>Xam</em> strain CIO151. Here, we show that the movement of bacteria along the tissues and especially in leaves is stochastic. Moreover, we were able to demonstrate differential growth of virulent <em>Xam</em> strain CIO151 upon stem-puncturing and quantification of bacteria 6 cm. away from the inoculation point of two varieties displaying contrasting levels of susceptibility.</p><p class="ecxmsonormal"><strong>RESUMEN</strong></p><p class="ecxmsonormal"><!--[if gte mso 9]><xml> <o:OfficeDocumentSettings> <o:AllowPNG/> </o:OfficeDocumentSettings> </xml><![endif]--></p><p class="msocomoff" align="left"><!--[if gte mso 9]><xml> <w:WordDocument> <w:View>Normal</w:View> <w:Zoom>0</w:Zoom> <w:TrackMoves/> <w:TrackFormatting/> <w:HyphenationZone>21</w:HyphenationZone> <w:PunctuationKerning/> <w:ValidateAgainstSchemas/> <w:SaveIfXMLInvalid>false</w:SaveIfXMLInvalid> <w:IgnoreMixedContent>false</w:IgnoreMixedContent> <w:AlwaysShowPlaceholderText>false</w:AlwaysShowPlaceholderText> <w:DoNotPromoteQF/> <w:LidThemeOther>ES-CO</w:LidThemeOther> <w:LidThemeAsian>X-NONE</w:LidThemeAsian> 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<w:LsdException Locked="false" Priority="39" QFormat="true" Name="TOC Heading"/> </w:LatentStyles> </xml><![endif]--><!--[if !supportAnnotations]--><!--[endif]--><!--[if gte mso 10]> <style> /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Tabla normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-priority:99; mso-style-qformat:yes; mso-style-parent:""; mso-padding-alt:0cm 5.4pt 0cm 5.4pt; mso-para-margin:0cm; mso-para-margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:11.0pt; font-family:"Calibri","sans-serif"; mso-ascii-font-family:Calibri; mso-ascii-theme-font:minor-latin; mso-fareast-font-family:"Times New Roman"; mso-fareast-theme-font:minor-fareast; mso-hansi-font-family:Calibri; mso-hansi-theme-font:minor-latin; mso-bidi-font-family:"Times New Roman"; mso-bidi-theme-font:minor-bidi;} </style> <![endif]--></p><p class="EstiloActa" style="text-align: justify;"><em style="mso-bidi-font-style: normal;"><span lang="X-NONE">Xanthomonas axonopodis </span></em><span lang="X-NONE">pv. manihotis<em style="mso-bidi-font-style: normal;"> (Xam)</em> es el agente causal del tizón bacteriano de la yuca, una de las principales enfermedades de los cultivos de yuca en América del Sur y África. Hasta ahora, el desarrollo de la enfermedad se mide a través de AUDPC <em style="mso-bidi-font-style: normal;">(Area<span style="mso-spacerun: yes;"> </span>Under Disease Progress curve)</em>, pero no hay disponibles métodos cuantitativos fiables,<span style="mso-spacerun: yes;"> </span>esto debido posiblemente a la alta variabilidad del crecimiento bacteriano en la planta. Para establecer un método exacto para la cuantificación bacteriana durante el curso de la infección <em style="mso-bidi-font-style: normal;">Xam </em>dentro de los tejidos del huésped, se analizaron las poblaciones de bacterias sobre tallo y hojas, así como corte de hojas de las <a style="mso-comment-reference: as_1; mso-comment-date: 20141102T2035;">variedades de yuca</a></span><span lang="X-NONE">MCOL1522 y SG107-35 con la cepa virulenta CIO151 <em style="mso-bidi-font-style: normal;">Xam.</em> <a style="mso-comment-reference: as_2; mso-comment-date: 20141102T2035;">En esta investigación se </a></span><span lang="X-NONE">muestra que el movimiento de las bacterias a lo largo de los tejidos y especialmente en las hojas es estocástico. Por otra parte, hemos podido demostrar el crecimiento diferencial de la cepa virulenta<span style="mso-spacerun: yes;"> </span><em style="mso-bidi-font-style: normal;">Xam</em> CIO151 tras la punción al tallo y la cuantificación de la bacteria a 6 cm de distancia del punto de inoculación de dos variedades que presentan niveles contrastantes de susceptibilidad.</span></p><p class="ecxmsonormal"> </p>
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Cohn M, Bart RS, Shybut M, Dahlbeck D, Gomez M, Morbitzer R, Hou BH, Frommer WB, Lahaye T, Staskawicz BJ. Xanthomonas axonopodis virulence is promoted by a transcription activator-like effector-mediated induction of a SWEET sugar transporter in cassava. MOLECULAR PLANT-MICROBE INTERACTIONS : MPMI 2014; 27:1186-98. [PMID: 25083909 DOI: 10.1094/mpmi-06-14-0161-r] [Citation(s) in RCA: 152] [Impact Index Per Article: 15.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/18/2023]
Abstract
The gene-for-gene concept has historically been applied to describe a specific resistance interaction wherein single genes from the host and the pathogen dictate the outcome. These interactions have been observed across the plant kingdom and all known plant microbial pathogens. In recent years, this concept has been extended to susceptibility phenotypes in the context of transcription activator-like (TAL) effectors that target SWEET sugar transporters. However, because this interaction has only been observed in rice, it was not clear whether the gene-for-gene susceptibility was unique to that system. Here, we show, through a combined systematic analysis of the TAL effector complement of Xanthomonas axonopodis pv. manihotis and RNA sequencing to identify targets in cassava, that TAL20Xam668 specifically induces the sugar transporter MeSWEET10a to promote virulence. Designer TAL effectors (dTALE) complement TAL20Xam668 mutant phenotypes, demonstrating that MeSWEET10a is a susceptibility gene in cassava. Sucrose uptake-deficient X. axonopodis pv. manihotis bacteria do not lose virulence, indicating that sucrose may be cleaved extracellularly and taken up as hexoses into X. axonopodis pv. manihotis. Together, our data suggest that pathogen hijacking of plant nutrients is not unique to rice blight but also plays a role in bacterial blight of the dicot cassava.
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Genomic insights into the evolutionary origin of Xanthomonas axonopodis pv. citri and its ecological relatives. Appl Environ Microbiol 2014; 80:6266-79. [PMID: 25085494 DOI: 10.1128/aem.01654-14] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Xanthomonas axonopodis pv. citri (Xac) is the causal agent of citrus bacterial canker (CBC) and is a serious problem worldwide. Like CBC, several important diseases in other fruits, such as mango, pomegranate, and grape, are also caused by Xanthomonas pathovars that display remarkable specificity toward their hosts. While citrus and mango diseases were documented more than 100 years ago, the pomegranate and grape diseases have been known only since the 1950s and 1970s, respectively. Interestingly, diseases caused by all these pathovars were noted first in India. Our genome-based phylogenetic studies suggest that these diverse pathogens belong to a single species and these pathovars may be just a group of rapidly evolving strains. Furthermore, the recently reported pathovars, such as those infecting grape and pomegranate, form independent clonal lineages, while the citrus and mango pathovars that have been known for a long time form one clonal lineage. Such an understanding of their phylogenomic relationship has further allowed us to understand major and unique variations in the lineages that give rise to these pathovars. Whole-genome sequencing studies including ecological relatives from their putative country of origin has allowed us to understand the evolutionary history of Xac and other pathovars that infect fruits.
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Trujillo CA, Ochoa JC, Mideros MF, Restrepo S, López C, Bernal A. A complex population structure of the cassava pathogen Xanthomonas axonopodis pv. manihotis in recent years in the Caribbean Region of Colombia. MICROBIAL ECOLOGY 2014; 68:155-67. [PMID: 24760168 DOI: 10.1007/s00248-014-0411-8] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/22/2013] [Accepted: 03/11/2014] [Indexed: 05/13/2023]
Abstract
Cassava bacterial blight, caused by Xanthomonas axonopodis pv. manihotis (Xam), is the most important bacterial disease affecting this crop. A continuous surveillance of the pathogen population dynamics is required to develop an efficient disease management program. During the 1990s, Xam populations showed high levels of genetic variation and relevant migratory processes that were important determinants of the distribution of the pathogen diversity in Colombia. Aiming to characterize the current population structure of the pathogen and the evolutionary forces that shape these populations, sampling collections were carried out from September 2008 until November 2010 in the Colombian Caribbean Region. One hundred and sixty bacterial isolates were characterized using amplified fragment length polymorphism (AFLP) markers. Additionally, a subset of effector genes were sequenced in some isolates to determine their usefulness in Xam population studies and to provide additional information to that obtained with AFLPs. Virulence patterns of ten isolates were determined in nine cassava accessions. Our results show a complex architecture of population and confirm migratory process previously reported in the Caribbean Region. Chinú, one of the locations sampled, presented remarkable features in population dynamics such as longer genetic distances, higher diversity indices, and a genetically differentiated population when it was compared with other locations. Virulence tests showed that MCOL2215, one of the most cultivated cassava varieties in the Caribbean coast, was susceptible to the majority of Xam isolates tested. This study shows the current condition of populations of Xam in the Caribbean Region of Colombia, and it contributes to improve the existing bacterial blight control practices.
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Affiliation(s)
- César A Trujillo
- Laboratorio de Micología y Fitopatología Uniandes (LAMFU), Universidad de Los Andes, Bogotá, Colombia,
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Trujillo CA, Arias-Rojas N, Poulin L, Medina CA, Tapiero A, Restrepo S, Koebnik R, Bernal AJ. Population typing of the causal agent of cassava bacterial blight in the Eastern Plains of Colombia using two types of molecular markers. BMC Microbiol 2014; 14:161. [PMID: 24946775 PMCID: PMC4071214 DOI: 10.1186/1471-2180-14-161] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2013] [Accepted: 06/10/2014] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Molecular typing of pathogen populations is an important tool for the development of effective strategies for disease control. Diverse molecular markers have been used to characterize populations of Xanthomonas axonopodis pv. manihotis (Xam), the main bacterial pathogen of cassava. Recently, diversity and population dynamics of Xam in the Colombian Caribbean coast were estimated using AFLPs, where populations were found to be dynamic, diverse and with haplotypes unstable across time. Aiming to examine the current state of pathogen populations located in the Colombian Eastern Plains, we also used AFLP markers and we evaluated the usefulness of Variable Number Tandem Repeats (VNTRs) as new molecular markers for the study of Xam populations. RESULTS The population analyses showed that AFLP and VNTR provide a detailed and congruent description of Xam populations from the Colombian Eastern Plains. These two typing strategies clearly separated strains from the Colombian Eastern Plains into distinct populations probably because of geographical distance. Although the majority of analyses were congruent between typing markers, fewer VNTRs were needed to detect a higher number of genetic populations of the pathogen as well as a higher genetic flow among sampled locations than those detected by AFLPs. CONCLUSIONS This study shows the advantages of VNTRs over AFLPs in the surveillance of pathogen populations and suggests the implementation of VNTRs in studies that involve large numbers of Xam isolates in order to obtain a more detailed overview of the pathogen to improve the strategies for disease control.
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Affiliation(s)
| | | | | | | | | | | | | | - Adriana J Bernal
- Laboratorio de Micología y Fitopatología Uniandes (LAMFU), Universidad de Los Andes, Bogotá, Colombia.
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