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Senuma W, Hayashi K, Tsuzuki M, Takemura C, Terazawa Y, Kiba A, Ohnishi K, Kai K, Hikichi Y. Contribution of the Sensor Histidine Kinases PhcS and VsrA to the Quorum Sensing of Ralstonia pseudosolanacearum Strain OE1-1. MOLECULAR PLANT-MICROBE INTERACTIONS : MPMI 2024; 37:688-697. [PMID: 39295141 DOI: 10.1094/mpmi-05-24-0049-r] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 09/21/2024]
Abstract
The soilborne Gram-negative phytopathogenic beta-proteobacterium Ralstonia pseudosolanacearum strain OE1-1 produces methyl 3-hydroxymyristate (3-OH MAME) as the quorum sensing (QS) signal by the methyltransferase PhcB and senses the chemical, activating the LysR family transcriptional regulator PhcA, which regulates the QS-dependent genes responsible for QS-dependent phenotypes including virulence. The sensor histidine kinases PhcS and VsrA are reportedly involved in the regulation of QS-dependent genes. To elucidate the function of PhcS and VsrA in the active QS, we generated the phcS-deletion and vsrA-deletion mutants, which exhibited weak changes to their QS-dependent phenotypes including virulence. The phcS and vsrA-deletion mutant (ΔphcS/vsrA) had significant changes in its QS-dependent phenotypes and was nonvirulent, similar to the phcA-deletion mutant. The mutant (PhcS-H230Q) with a substitution of histidine to glutamine at amino acid position 230 in PhcS but not the mutant (VsrA-H256Q) with a substitution of histidine to glutamine at amino acid position 256 in VsrA exhibited significant changes in QS-dependent phenotypes and lost virulence. The transcriptome analysis with RNA-sequencing revealed significant alterations to the expression of QS-dependent genes in the ΔphcS/vsrA and PhcS-H230Q but not VsrA-H256Q, similar to the phcA-deletion mutant. The exogenous 3-OH MAME application led to a significantly enhanced QS-inducible major exopolysaccharide EPS I production of the strain OE1-1 and phcB-deletion mutant but not ΔphcS/vsrA and PhcS-H230Q. Collectively, results of the present genetic study suggested that PhcS contributes to QS along with VsrA and that histidine at amino acid position 230 of PhcS is required for 3-OH MAME sensing, thereby influencing QS-dependent phenotypes including virulence of the strain OE1-1. [Formula: see text] The author(s) have dedicated the work to the public domain under the Creative Commons CC0 "No Rights Reserved" license by waiving all of his or her rights to the work worldwide under copyright law, including all related and neighboring rights, to the extent allowed by law, 2024.
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Affiliation(s)
- Wakana Senuma
- Faculty of Agriculture and Marine Science, Kochi University, Nankoku, Japan
| | - Kazusa Hayashi
- Faculty of Agriculture and Marine Science, Kochi University, Nankoku, Japan
| | - Masayuki Tsuzuki
- Faculty of Agriculture and Marine Science, Kochi University, Nankoku, Japan
| | - Chika Takemura
- Faculty of Agriculture and Marine Science, Kochi University, Nankoku, Japan
| | - Yuki Terazawa
- Faculty of Agriculture and Marine Science, Kochi University, Nankoku, Japan
| | - Akinori Kiba
- Faculty of Agriculture and Marine Science, Kochi University, Nankoku, Japan
| | - Kouhei Ohnishi
- Faculty of Agriculture and Marine Science, Kochi University, Nankoku, Japan
| | - Kenji Kai
- Graduate School of Agriculture, Osaka Metropolitan University, Sakai, Japan
| | - Yasufumi Hikichi
- Faculty of Agriculture and Marine Science, Kochi University, Nankoku, Japan
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Thomas G, Kay WT, Fones HN. Life on a leaf: the epiphyte to pathogen continuum and interplay in the phyllosphere. BMC Biol 2024; 22:168. [PMID: 39113027 PMCID: PMC11304629 DOI: 10.1186/s12915-024-01967-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2024] [Accepted: 08/01/2024] [Indexed: 08/11/2024] Open
Abstract
Epiphytic microbes are those that live for some or all of their life cycle on the surface of plant leaves. Leaf surfaces are a topologically complex, physicochemically heterogeneous habitat that is home to extensive, mixed communities of resident and transient inhabitants from all three domains of life. In this review, we discuss the origins of leaf surface microbes and how different biotic and abiotic factors shape their communities. We discuss the leaf surface as a habitat and microbial adaptations which allow some species to thrive there, with particular emphasis on microbes that occupy the continuum between epiphytic specialists and phytopathogens, groups which have considerable overlap in terms of adapting to the leaf surface and between which a single virulence determinant can move a microbial strain. Finally, we discuss the recent findings that the wheat pathogenic fungus Zymoseptoria tritici spends a considerable amount of time on the leaf surface, and ask what insights other epiphytic organisms might provide into this pathogen, as well as how Z. tritici might serve as a model system for investigating plant-microbe-microbe interactions on the leaf surface.
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Affiliation(s)
| | - William T Kay
- Department of Plant Sciences, University of Oxford, Oxford, UK
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Jin C, Matsuo H, Nakayama Y, Shigita G, Inoue Y, Kato K, Takano Y. A deletion in FLS2 and its expansion after domestication caused global dissemination of melon cultivars defective in flagellin recognition. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2024; 119:1671-1684. [PMID: 38924650 DOI: 10.1111/tpj.16895] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/11/2024] [Revised: 04/30/2024] [Accepted: 06/13/2024] [Indexed: 06/28/2024]
Abstract
FLAGELLIN SENSING 2 (FLS2) encodes a pattern recognition receptor that perceives bacterial flagellin. While putative FLS2 orthologs are broadly conserved in plants, their functional characterization remains limited. Here, we report the identification of orthologs in cucumber (Cucumis sativus) and melon (C. melo), named CsFLS2 and CmFLS2, respectively. Homology searching identified CsFLS2, and virus-induced gene silencing (VIGS) demonstrated that CsFLS2 is required for flg22-triggered ROS generation. Interestingly, genome re-sequencing of melon cv. Lennon and subsequent genomic PCR revealed that Lennon has two CmFLS2 haplotypes, haplotype I encoding full-length CmFLS2 and haplotype II encoding a truncated form. We show that VIGS-mediated knockdown of CmFLS2 haplotype I resulted in a significant reduction in both flg22-triggered ROS generation and immunity to a bacterial pathogen in melon cv. Lennon. Remarkably, genomic PCR of CmFLS2 revealed that 68% of tested commercial melon cultivars possess only CmFLS2 haplotype II: these cultivars thus lack functional CmFLS2. To explore evolutionary aspects of CmFLS2 haplotype II occurrence, we genotyped the CmFLS2 locus in 142 melon accessions by genomic PCR and analyzed 437 released sequences. The results suggest that CmFLS2 haplotype II is derived from C. melo subsp. melo. Furthermore, we suggest that the proportion of CmFLS2 haplotype II increased among the improved melo group compared with the primitive melo group. Collectively, these findings suggest that the deleted FLS2 locus generated in the primitive melo subspecies expanded after domestication, resulting in the spread of commercial melon cultivars defective in flagellin recognition, which is critical for bacterial immunity.
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Affiliation(s)
- Chujia Jin
- Laboratory of Plant Pathology, Graduate School of Agriculture, Kyoto University, Kyoto, 606-8502, Japan
| | - Hiroki Matsuo
- Laboratory of Plant Pathology, Graduate School of Agriculture, Kyoto University, Kyoto, 606-8502, Japan
| | - Yoshizo Nakayama
- Laboratory of Plant Pathology, Graduate School of Agriculture, Kyoto University, Kyoto, 606-8502, Japan
| | - Gentaro Shigita
- Laboratory of Plant Biodiversity Research, Department of Life Science Systems, Technical University of Munich, Freising, 85354, Germany
- Faculty of Life and Environmental Sciences, University of Tsukuba, Ibaraki, 305-8572, Japan
| | - Yoshihiro Inoue
- Laboratory of Plant Genetics, Graduate School of Agriculture, Kyoto University, Kyoto, 606-8502, Japan
| | - Kenji Kato
- Graduate School of Environmental, Life, Natural Science and Technology, Okayama University, 1-1-1 Tsushima Naka, Kita-ku, Okayama, 700-8530, Japan
| | - Yoshitaka Takano
- Laboratory of Plant Pathology, Graduate School of Agriculture, Kyoto University, Kyoto, 606-8502, Japan
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Li P, Bez C, Zhang Y, Deng Y, Venturi V. N-acyl homoserine lactone cell-cell diffusible signalling in the Ralstonia solanacearum species complex. MOLECULAR PLANT PATHOLOGY 2024; 25:e13467. [PMID: 39099210 PMCID: PMC11298618 DOI: 10.1111/mpp.13467] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/21/2023] [Revised: 04/29/2024] [Accepted: 04/29/2024] [Indexed: 08/06/2024]
Abstract
Ralstonia solanacearum species complex (RSSC) includes soilborne bacterial plant pathogens with worldwide distribution and wide host ranges. Virulence factors are regulated via four hierarchically organized cell-cell contact independent quorum-sensing (QS) signalling systems: the Phc, which uses as signals (R)-methyl 3-hydroxypalmitate [(R)-3-OH PAME] or (R)-methyl 3-hydroxymyristate [(R)-3-OH MAME], the N-acyl homoserine lactone (AHL)-dependent RasI/R and SolI/R systems, and the recently identified anthranilic acid-dependent system. The unique Phc QS system has been extensively studied; however, the role of the two AHL QS systems has only recently been addressed. In this microreview, we present and discuss current data of the SolI/R and RasI/R QS systems in the RSSC. We also present the distribution and frequency of these AHL QS systems in the RSSC, discuss possible ecological roles and evolutive implications. The complex QS hierarchical networks emphasizes the crucial role of cell-cell signalling in the virulence of the RSSC.
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Affiliation(s)
- Peng Li
- Ministry of Education Key Laboratory for Ecology of Tropical Islands, Key Laboratory of Tropical Animal and Plant Ecology of Hainan Province, College of Life SciencesHainan Normal UniversityHaikouChina
- International Centre for Genetic Engineering and BiotechnologyTriesteItaly
| | - Cristina Bez
- International Centre for Genetic Engineering and BiotechnologyTriesteItaly
| | - Yong Zhang
- Interdisciplinary Research Center for Agriculture Green Development in Yangtze River BasinSouthwest UniversityChongqingChina
| | - Yinyue Deng
- School of Pharmaceutical Sciences (Shenzhen)Shenzhen Campus of Sun Yat‐sen University, Sun Yatsen UniversityShenzhenChina
| | - Vittorio Venturi
- International Centre for Genetic Engineering and BiotechnologyTriesteItaly
- African Genome Center, University Mohammed VI Polytechnic (UM6P)Ben GuerirMorocco
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Ferreira MV, Naranjo E, Denis N, Cobine P, De La Fuente L, Siri MI. Calcium modulation of bacterial wilt disease on potato. Appl Environ Microbiol 2024; 90:e0024224. [PMID: 38690890 PMCID: PMC11107177 DOI: 10.1128/aem.00242-24] [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: 02/19/2024] [Accepted: 03/22/2024] [Indexed: 05/03/2024] Open
Abstract
Ralstonia solanacearum species complex (RSSC) is a phytopathogenic bacterial group that causes bacterial wilt in several crops, being potato (Solanum tuberosum) one of the most important hosts. The relationship between the potato plant ionome (mineral and trace elements composition) and the resistance levels to this pathogen has not been addressed until now. Mineral content of xylem sap, roots, stems and leaves of potato genotypes with different levels of resistance to bacterial wilt was assessed in this work, revealing a positive correlation between divalent calcium (Ca) cation concentrations and genotype resistance. The aim of this study was to investigate the effect of Ca on bacterial wilt resistance, and on the growth and virulence of RSSC. Ca supplementation significantly decreased the growth rate of Ralstonia pseudosolanacearum GMI1000 in minimal medium and affected several virulence traits such as biofilm formation and twitching motility. We also incorporate for the first time the use of microfluidic chambers to follow the pathogen growth and biofilm formation in conditions mimicking the plant vascular system. By using this approach, a reduction in biofilm formation was observed when both, rich and minimal media, were supplemented with Ca. Assessment of the effect of Ca amendments on bacterial wilt progress in potato genotypes revealed a significant delay in disease progress, or a complete absence of wilting symptoms in the case of partially resistant genotypes. This work contributes to the understanding of Ca effect on virulence of this important pathogen and provides new strategies for an integrated control of bacterial wilt on potato. IMPORTANCE Ralstonia solanacearum species complex (RSSC) includes a diverse group of bacterial strains that cause bacterial wilt. This disease is difficult to control due to pathogen aggressiveness, persistence, wide range of hosts, and wide geographic distribution in tropical, subtropical, and temperate regions. RSSC causes considerable losses depending on the pathogen strain, host, soil type, environmental conditions, and cultural practices. In potato, losses of $19 billion per year have been estimated for this pathogen worldwide. In this study, we report for the first time the mineral composition found in xylem sap and plant tissues of potato germplasm with different levels of resistance to bacterial wilt. This study underscores the crucial role of calcium (Ca) concentration in the xylem sap and stem in relation to the resistance of different genotypes. Our in vitro experiments provide evidence of Ca's inhibitory effect on the growth, biofilm formation, and twitching movement of the model RSSC strain R. pseudosolanacearum GMI1000. This study introduces a novel element, the Ca concentration, which should be included into the integrated disease control management strategies for bacterial wilt in potatoes.
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Affiliation(s)
- María Virginia Ferreira
- Área Microbiología, Departamento de Biociencias, Facultad de Química, Universidad de la República, Montevideo, Uruguay
| | - Eber Naranjo
- Department of Entomology and Plant Pathology, Auburn University, Auburn, Alabama, USA
| | - Nicol Denis
- Área Microbiología, Departamento de Biociencias, Facultad de Química, Universidad de la República, Montevideo, Uruguay
| | - Paul Cobine
- Department of Biological Sciences, Auburn University, Auburn, Alabama, USA
| | - Leonardo De La Fuente
- Department of Entomology and Plant Pathology, Auburn University, Auburn, Alabama, USA
| | - María Inés Siri
- Área Microbiología, Departamento de Biociencias, Facultad de Química, Universidad de la República, Montevideo, Uruguay
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Yadav M, Sathe J, Teronpi V, Kumar A. Navigating the signaling landscape of Ralstonia solanacearum: a study of bacterial two-component systems. World J Microbiol Biotechnol 2024; 40:153. [PMID: 38564115 DOI: 10.1007/s11274-024-03950-y] [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: 01/16/2024] [Accepted: 03/10/2024] [Indexed: 04/04/2024]
Abstract
Ralstonia solanacearum, the bacterium that causes bacterial wilt, is a destructive phytopathogen that can infect over 450 different plant species. Several agriculturally significant crop plants, including eggplant, tomato, pepper, potato, and ginger, are highly susceptible to this plant disease, which has a global impact on crop quality and yield. There is currently no known preventive method that works well for bacterial wilt. Bacteria use two-component systems (TCSs) to sense their environment constantly and react appropriately. This is achieved by an extracellular sensor kinase (SK) capable of sensing a suitable signal and a cytoplasmic response regulator (RR) which gives a downstream response. Moreover, our investigation revealed that R. solanacearum GMI1000 possesses a substantial count of TCSs, specifically comprising 36 RRs and 27 SKs. While TCSs are known targets for various human pathogenic bacteria, such as Salmonella, the role of TCSs in R. solanacearum remains largely unexplored in this context. Notably, numerous inhibitors targeting TCSs have been identified, including GHL (Gyrase, Hsp, and MutL) compounds, Walk inhibitors, and anti-TCS medications like Radicicol. Consequently, the investigation into the involvement of TCSs in virulence and pathogenesis has gained traction; however, further research is imperative to ascertain whether TCSs could potentially supplant conventional anti-wilt therapies. This review delves into the prospective utilization of TCSs as an alternative anti-wilt therapy, focusing on the lethal phytopathogen R. solanacearum.
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Affiliation(s)
- Mohit Yadav
- Department of Molecular Biology and Biotechnology, Tezpur University, Tezpur, Assam, 784028, India
| | - Janhavi Sathe
- Department of Molecular Biology and Biotechnology, Tezpur University, Tezpur, Assam, 784028, India
- Institute for Stem Cell Science and Regenerative Medicine, Bangalore, Karnataka, 560065, India
| | - Valentina Teronpi
- Department of Zoology, Pandit Deendayal Upadhyaya Adarsha Mahavidyalaya, Behali, Biswanath, Assam, 784184, India
| | - Aditya Kumar
- Department of Molecular Biology and Biotechnology, Tezpur University, Tezpur, Assam, 784028, India.
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Yang J, Chen R, Wang C, Li C, Ye W, Zhang Z, Wang S. A widely targeted metabolite modificomics strategy for modified metabolites identification in tomato. JOURNAL OF INTEGRATIVE PLANT BIOLOGY 2024; 66:810-823. [PMID: 38375781 DOI: 10.1111/jipb.13629] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/07/2023] [Accepted: 02/04/2024] [Indexed: 02/21/2024]
Abstract
The structural and functional diversity of plant metabolites is largely created via chemical modification of a basic backbone. However, metabolite modifications in plants have still not been thoroughly investigated by metabolomics approaches. In this study, a widely targeted metabolite modificomics (WTMM) strategy was developed based on ultra-high performance liquid chromatography-quadrupole-linear ion trap (UHPLC-Q-Trap) and UHPLC-Q-Exactive-Orbitrap (UHPLC-QE-Orbitrap), which greatly improved the detection sensitivity and the efficiency of identification of modified metabolites. A metabolite modificomics study was carried out using tomato as a model, and over 34,000 signals with MS2 information were obtained from approximately 232 neutral loss transitions. Unbiased metabolite profiling was also performed by utilizing high-resolution mass spectrometry data to annotate a total of 2,118 metabolites with 125 modification types; of these, 165 modified metabolites were identified in this study. Next, the WTMM database was used to assess diseased tomato tissues and 29 biomarkers were analyzed. In summary, the WTMM strategy is not only capable of large-scale detection and quantitative analysis of plant-modified metabolites in plants, but also can be used for plant biomarker development.
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Affiliation(s)
- Jun Yang
- School of Breeding and Multiplication (Sanya Institute of Breeding and Multiplication), Hainan University, Sanya, 572025, China
- School of Tropical Agriculture and Forestry, Hainan University, Haikou, 572208, China
| | - Ridong Chen
- School of Breeding and Multiplication (Sanya Institute of Breeding and Multiplication), Hainan University, Sanya, 572025, China
- School of Tropical Agriculture and Forestry, Hainan University, Haikou, 572208, China
| | - Chao Wang
- School of Breeding and Multiplication (Sanya Institute of Breeding and Multiplication), Hainan University, Sanya, 572025, China
- School of Tropical Agriculture and Forestry, Hainan University, Haikou, 572208, China
| | - Chun Li
- School of Breeding and Multiplication (Sanya Institute of Breeding and Multiplication), Hainan University, Sanya, 572025, China
- School of Tropical Agriculture and Forestry, Hainan University, Haikou, 572208, China
| | - Weizhen Ye
- School of Breeding and Multiplication (Sanya Institute of Breeding and Multiplication), Hainan University, Sanya, 572025, China
- School of Tropical Agriculture and Forestry, Hainan University, Haikou, 572208, China
| | - Zhonghui Zhang
- School of Breeding and Multiplication (Sanya Institute of Breeding and Multiplication), Hainan University, Sanya, 572025, China
- School of Tropical Agriculture and Forestry, Hainan University, Haikou, 572208, China
| | - Shouchuang Wang
- School of Breeding and Multiplication (Sanya Institute of Breeding and Multiplication), Hainan University, Sanya, 572025, China
- School of Tropical Agriculture and Forestry, Hainan University, Haikou, 572208, China
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Siddique MI, Silverman E, Louws F, Panthee DR. Quantitative Trait Loci Mapping for Bacterial Wilt Resistance and Plant Height in Tomatoes. PLANTS (BASEL, SWITZERLAND) 2024; 13:876. [PMID: 38592886 PMCID: PMC10976105 DOI: 10.3390/plants13060876] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/26/2024] [Revised: 03/13/2024] [Accepted: 03/14/2024] [Indexed: 04/11/2024]
Abstract
Bacterial wilt (BW) of tomatoes, caused by Ralstonia solanacearum, is a devastating disease that results in large annual yield losses worldwide. Management of BW of tomatoes is difficult due to the soil-borne nature of the pathogen. One of the best ways to mitigate the losses is through breeding for disease resistance. Moreover, plant height (PH) is a crucial element related to plant architecture, which determines nutrient management and mechanical harvesting in tomatoes. An intraspecific F2 segregating population (NC 11212) of tomatoes was developed by crossing NC 84173 (tall, BW susceptible) × CLN1466EA (short, BW resistant). We performed quantitative trait loci (QTL) mapping using single nucleotide polymorphic (SNP) markers and the NC 11212 F2 segregating population. The QTL analysis for BW resistance revealed a total of three QTLs on chromosomes 1, 2, and 3, explaining phenotypic variation (R2) ranging from 3.6% to 14.9%, whereas the QTL analysis for PH also detected three QTLs on chromosomes 1, 8, and 11, explaining R2 ranging from 7.1% to 11%. This work thus provides information to improve BW resistance and plant architecture-related traits in tomatoes.
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Affiliation(s)
- Muhammad Irfan Siddique
- Mountain Horticultural Crops Research and Extension Center, Department of Horticultural Science, North Carolina State University, 455 Research Dr., Mills River, NC 28759, USA
| | - Emily Silverman
- Department of Plant Pathology, North Carolina State University, Raleigh, NC 27695, USA
| | - Frank Louws
- Mountain Horticultural Crops Research and Extension Center, Department of Horticultural Science, North Carolina State University, 455 Research Dr., Mills River, NC 28759, USA
- Department of Plant Pathology, North Carolina State University, Raleigh, NC 27695, USA
| | - Dilip R. Panthee
- Mountain Horticultural Crops Research and Extension Center, Department of Horticultural Science, North Carolina State University, 455 Research Dr., Mills River, NC 28759, USA
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Bhatt S, Raj SMP, Faridi N, Pathak D, Agarwal A, Mishra SP. Development of antibody to virulence factor flagellin and its evaluation in screening Ralstonia pseudosolanacearum. Braz J Microbiol 2024; 55:809-821. [PMID: 38233641 PMCID: PMC10920531 DOI: 10.1007/s42770-023-01235-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2023] [Accepted: 12/26/2023] [Indexed: 01/19/2024] Open
Abstract
The bacterial wilt disease caused by Ralstonia pseudosolanacearum presents a notable economic risk to a variety of crucial crops worldwide. During preliminary isolation of this phytopathogen, several colonies of other saprophytic bacteria may be mistaken with it. So, the present study aims to address this issue by proposing the application of immunogenic proteins, particularly flagellin (FliC), to enable a rapid and early identification of bacterial wilt. In this study, a novel approach is unveiled for the early detection of R. pseudosolanacearum. The study exploits the immunogenic attributes of flagellin (FliC), by generating polyclonal antibodies against recombinant FliC within model organisms-rabbits and mice. The efficacy of these antibodies is meticulously assessed through discerning techniques, including DAS-ELISA and Western blot analyses, which elucidate their remarkable specificity in identifying various R. pseudosolanacearum strains. Furthermore, the introduction of antibody-coated latex agglutinating reagents offers an additional layer of confirmation, substantiating the feasibility of establishing a laboratory-based toolkit for swift screening and unambiguous identification of the bacterial wilt pathogen. This study presents a significant stride toward enhancing early diagnostic capabilities, potentially revolutionizing agricultural practices by safeguarding crop yield and quality through proactive pathogen detection and mitigation strategies.
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Affiliation(s)
- Shalini Bhatt
- P P Savani University, Surat, Gujarat, 394125, India.
- Defence Institute of Bio-Energy Research (DIBER), DRDO, Haldwani, Nainital, Uttarakhand, 263139, India.
| | - S Merwyn P Raj
- Defence Institute of Bio-Energy Research (DIBER), DRDO, Haldwani, Nainital, Uttarakhand, 263139, India
| | - Neha Faridi
- Defence Institute of Bio-Energy Research (DIBER), DRDO, Haldwani, Nainital, Uttarakhand, 263139, India
| | - Dinesh Pathak
- Defence Institute of Bio-Energy Research (DIBER), DRDO, Haldwani, Nainital, Uttarakhand, 263139, India
| | - Ankur Agarwal
- Defence Institute of Bio-Energy Research (DIBER), DRDO, Haldwani, Nainital, Uttarakhand, 263139, India
| | - Shraddha P Mishra
- Defence Institute of Bio-Energy Research (DIBER), DRDO, Haldwani, Nainital, Uttarakhand, 263139, India
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10
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Bhatt S, Faridi N, Raj SMP, Agarwal A, Punetha M. Recent advances in immuno-based methods for the detection of Ralstonia solanacearum. J Microbiol Methods 2024; 217-218:106889. [PMID: 38211840 DOI: 10.1016/j.mimet.2024.106889] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2023] [Revised: 01/08/2024] [Accepted: 01/08/2024] [Indexed: 01/13/2024]
Abstract
Ralstonia solanacearum (RS) is a widely recognized phytopathogenic bacterium which is responsible for causing devastating losses in a wide range of economically significant crops. Timely and accurate detection of this pathogen is pivotal to implementing effective disease management strategies and preventing crop losses. This review provides a comprehensive overview of recent advances in immuno-based detection methods for RS. The review begins by introducing RS, highlighting its destructive potential and the need for point-of-care detection techniques. Subsequently, it explores traditional detection methods and their limitations, emphasizing the need for innovative approaches. The main focus of this review is on immuno-based detection methods and it discusses recent advancements in serological detection techniques. Furthermore, the review sheds light on the challenges and prospects of immuno-based detection of RS. It emphasizes the importance of developing rapid, field-deployable assays that can be used by farmers and researchers alike. In conclusion, this review provides valuable insights into the recent advances in immuno-based detection methods for RS.
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Affiliation(s)
- Shalini Bhatt
- P P Savani University, Surat 394125, Gujarat, India; Defence Institute of Bio-Energy Research (DIBER), DRDO, Nainital, Haldwani 263139, Uttarakhand, India.
| | - Neha Faridi
- Defence Institute of Bio-Energy Research (DIBER), DRDO, Nainital, Haldwani 263139, Uttarakhand, India
| | - S Merwyn P Raj
- Defence Institute of Bio-Energy Research (DIBER), DRDO, Nainital, Haldwani 263139, Uttarakhand, India
| | - Ankur Agarwal
- Defence Institute of Bio-Energy Research (DIBER), DRDO, Nainital, Haldwani 263139, Uttarakhand, India
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Bhuyan S, Dutta L, Begum S, Giri SJ, Jain M, Mandal M, Ray SK. A study on twitching motility dynamics in Ralstonia solanacearum microcolonies by live imaging. J Basic Microbiol 2024; 64:42-49. [PMID: 37612794 DOI: 10.1002/jobm.202300272] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2023] [Revised: 07/15/2023] [Accepted: 08/13/2023] [Indexed: 08/25/2023]
Abstract
Ralstonia solanacearum is a rod-shaped phytopathogenic bacterium that causes lethal wilt disease in many plants. On solid agar growth medium, in the early hour of the growth of the bacterial colony, the type IV pili-mediated twitching motility, which is important for its virulence and biofilm formation, is prominently observed under the microscope. In this study, we have done a detailed observation of twitching motility in R. solanacearum colony. In the beginning, twitching motility in the microcolonies was observed as a density-dependent phenomenon that influences the shape of the microcolonies. No such phenomenon was observed in Escherichia coli, where twitching motility is absent. In the early phase of colony growth, twitching motility exhibited by the cells at the peripheral region of the colony was more prominent than the cells toward the center of the colony. Using time-lapse photography and merging the obtained photomicrographs into a video, twitching motility was observed as an intermittent phenomenon that progresses in layers in all directions as finger-like projections at the peripheral region of a bacterial colony. Each layer of bacteria twitches on top of the other and produces a multilayered film-like appearance. We found that the duration between the emergence of each layer diminishes progressively as the colony becomes older. This study on twitching motility demonstrates distinctly heterogeneity among the cells within a colony regarding their dynamics and the influence of microcolonies on each other regarding their morphology.
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Affiliation(s)
- Shuvam Bhuyan
- Department of Molecular Biology and Biotechnology, Tezpur University, Tezpur, Assam, India
| | - Lukapriya Dutta
- Department of Molecular Biology and Biotechnology, Tezpur University, Tezpur, Assam, India
| | - Shuhada Begum
- Department of Molecular Biology and Biotechnology, Tezpur University, Tezpur, Assam, India
| | - Shubhra J Giri
- Department of Molecular Biology and Biotechnology, Tezpur University, Tezpur, Assam, India
| | - Monika Jain
- Department of Molecular Biology and Biotechnology, Tezpur University, Tezpur, Assam, India
| | - Manabendra Mandal
- Department of Molecular Biology and Biotechnology, Tezpur University, Tezpur, Assam, India
| | - Suvendra K Ray
- Department of Molecular Biology and Biotechnology, Tezpur University, Tezpur, Assam, India
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Liang X, Wei F, Yang H, Fan L, Cai X, Ma Y, Shi J, Xing K, Qiu L, Li X, Lu L, Ji J, Wen Y, Feng J. Flagella-Driven Motility Is Critical to the Virulence of Xanthomonas fragariae in Strawberry. PLANT DISEASE 2023; 107:3506-3516. [PMID: 37157097 DOI: 10.1094/pdis-03-23-0409-re] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/10/2023]
Abstract
Xanthomonas fragariae (X. fragariae) is the causal agent of angular leaf spots (ALS) in strawberry plants. Recently, a study in China isolated X. fragariae strain YL19, which was observed to cause both typical ALS symptoms and dry cavity rot in strawberry crown tissue; this was the first X. fragariae strain to have both these effects in strawberry. In this study, from 2020 to 2022, we isolated 39 X. fragariae strains from diseased strawberries in different production areas in China. Multilocus sequence typing (MLST) and phylogenetic analysis showed that X. fragariae strain YLX21 was genetically different from YL19 and other strains. Tests indicated that YLX21 and YL19 had different pathogenicities toward strawberry leaves and stem crowns. YLX21 did not cause ALS symptoms, rarely caused dry cavity rot in strawberry crown after wound inoculation, and never caused dry cavity rot after spray inoculation, but it did cause severe ALS symptoms after spray inoculation. However, YL19 caused more severe symptoms in strawberry crowns under both conditions. Moreover, YL19 had a single polar flagellum, while YLX21 had no flagellum. Motility and chemotaxis assays showed that YLX21 had weaker motility than YL19, which may explain why YLX21 tended to multiply in situ within the strawberry leaf rather than migrate to other tissues, causing more severe ALS symptoms and mild crown rot symptoms. Taken together, the new strain YLX21 helped us reveal critical factors underlying the pathogenicity of X. fragariae and the mechanism by which dry cavity rot in strawberry crowns forms.
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Affiliation(s)
- Xia Liang
- State Key Laboratory of Crop Stress Biology for Arid Areas, College of Horticulture, Northwest A&F University, Yangling 712100, Shaanxi, China
- Key Laboratory of Protected Horticulture Engineering in Northwest China, Ministry of Agriculture and Rural Affairs, Yangling 712100, Shaanxi, China
| | - Feng Wei
- State Key Laboratory of Crop Stress Biology for Arid Areas, College of Horticulture, Northwest A&F University, Yangling 712100, Shaanxi, China
- Key Laboratory of Protected Horticulture Engineering in Northwest China, Ministry of Agriculture and Rural Affairs, Yangling 712100, Shaanxi, China
| | - Hongliang Yang
- State Key Laboratory of Crop Stress Biology for Arid Areas, College of Horticulture, Northwest A&F University, Yangling 712100, Shaanxi, China
- Key Laboratory of Protected Horticulture Engineering in Northwest China, Ministry of Agriculture and Rural Affairs, Yangling 712100, Shaanxi, China
| | - Li Fan
- State Key Laboratory of Crop Stress Biology for Arid Areas, College of Horticulture, Northwest A&F University, Yangling 712100, Shaanxi, China
- Key Laboratory of Protected Horticulture Engineering in Northwest China, Ministry of Agriculture and Rural Affairs, Yangling 712100, Shaanxi, China
| | - Xiaolin Cai
- State Key Laboratory of Crop Stress Biology for Arid Areas, College of Horticulture, Northwest A&F University, Yangling 712100, Shaanxi, China
- Key Laboratory of Protected Horticulture Engineering in Northwest China, Ministry of Agriculture and Rural Affairs, Yangling 712100, Shaanxi, China
| | - Yangyang Ma
- State Key Laboratory of Crop Stress Biology for Arid Areas, College of Horticulture, Northwest A&F University, Yangling 712100, Shaanxi, China
- Key Laboratory of Protected Horticulture Engineering in Northwest China, Ministry of Agriculture and Rural Affairs, Yangling 712100, Shaanxi, China
| | - Jiancheng Shi
- State Key Laboratory of Crop Stress Biology for Arid Areas, College of Horticulture, Northwest A&F University, Yangling 712100, Shaanxi, China
- Key Laboratory of Protected Horticulture Engineering in Northwest China, Ministry of Agriculture and Rural Affairs, Yangling 712100, Shaanxi, China
| | - Kun Xing
- State Key Laboratory of Crop Stress Biology for Arid Areas, College of Horticulture, Northwest A&F University, Yangling 712100, Shaanxi, China
- Key Laboratory of Protected Horticulture Engineering in Northwest China, Ministry of Agriculture and Rural Affairs, Yangling 712100, Shaanxi, China
| | - Lijuan Qiu
- State Key Laboratory of Crop Stress Biology for Arid Areas, College of Horticulture, Northwest A&F University, Yangling 712100, Shaanxi, China
- Key Laboratory of Protected Horticulture Engineering in Northwest China, Ministry of Agriculture and Rural Affairs, Yangling 712100, Shaanxi, China
| | - Xixuan Li
- State Key Laboratory of Crop Stress Biology for Arid Areas, College of Horticulture, Northwest A&F University, Yangling 712100, Shaanxi, China
- Key Laboratory of Protected Horticulture Engineering in Northwest China, Ministry of Agriculture and Rural Affairs, Yangling 712100, Shaanxi, China
| | - Lijuan Lu
- State Key Laboratory of Crop Stress Biology for Arid Areas, College of Horticulture, Northwest A&F University, Yangling 712100, Shaanxi, China
- Key Laboratory of Protected Horticulture Engineering in Northwest China, Ministry of Agriculture and Rural Affairs, Yangling 712100, Shaanxi, China
| | - Jie Ji
- Institute of Plant Protection, Fujian Academy of Agriculture Sciences, Fuzhou 350013, Fujian, China
| | - Yingqiang Wen
- State Key Laboratory of Crop Stress Biology for Arid Areas, College of Horticulture, Northwest A&F University, Yangling 712100, Shaanxi, China
| | - Jiayue Feng
- State Key Laboratory of Crop Stress Biology for Arid Areas, College of Horticulture, Northwest A&F University, Yangling 712100, Shaanxi, China
- Key Laboratory of Protected Horticulture Engineering in Northwest China, Ministry of Agriculture and Rural Affairs, Yangling 712100, Shaanxi, China
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Ren X, Zhou J, Liu T, Zhong C, Wang Y, Yan H, Feng J. Antibacterial activity and action mechanism of curcusionol from Carex siderosticta Hance against Ralstonia nicotianae. PEST MANAGEMENT SCIENCE 2023; 79:4607-4616. [PMID: 37436717 DOI: 10.1002/ps.7661] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/07/2023] [Revised: 06/30/2023] [Accepted: 07/12/2023] [Indexed: 07/13/2023]
Abstract
BACKGROUND Tobacco bacterial wilt is a typical soil-borne disease caused by Ralstonia nicotianae, which causes huge losses in tobacco production every year. The crude extract of Carex siderosticta Hance was shown to have antibacterial activity against R. nicotianae during our search, and the natural antibacterial components were sought after using bioassay-guided fractionation of the compounds. RESULT Ethanol extract of Carex siderosticta Hance with the minimum inhibitory concentration (MIC) value of 100 μg/mL against R. nicotianae in vitro. The potential of these compounds as antibactericides against R. nicotianae were assessed. Curcusionol (1), showed the highest antibacterial activity against R. nicotianae with MIC value of 12.5 μg/mL in vitro. In the protective effect tests, the control effect of curcusionol (1) was 92.31 and 72.60%, respectively, after application of 7 and 14 days, at a concentration of 1500 μg/mL, being comparable to that of streptomycin sulfate at a concentration of 500 μg/mL, confirming that curcusionol (1) showed the potential for the development of new antibacterial drugs. RNA-sequencing, scanning electron microscopy (SEM) and transmission electron microscopy (TEM) analysis confirmed that curcusionol mainly destroys R. nicotianae cell membrane structure and affects quorum sensing (QS) to inhibit pathogenic bacteria. CONCLUSION This study revealed that the antibacterial activity of Carex siderosticta Hance makes it a botanical bactericide against R. nicotianae, while curcusionol as lead structures for antibacterial development is obvious by its potent antibacterial activity. © 2023 Society of Chemical Industry.
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Affiliation(s)
- Xingyu Ren
- College of Plant Protection, Northwest A&F University, Xianyang, China
- Provincial Center for Bio-Pesticide Engineering, Northwest A&F University, Xianyang, China
| | - Juan Zhou
- College of Plant Protection, Northwest A&F University, Xianyang, China
- Provincial Center for Bio-Pesticide Engineering, Northwest A&F University, Xianyang, China
| | - Ting Liu
- College of Plant Protection, Northwest A&F University, Xianyang, China
- Provincial Center for Bio-Pesticide Engineering, Northwest A&F University, Xianyang, China
| | - Chenquan Zhong
- College of Plant Protection, Northwest A&F University, Xianyang, China
- Provincial Center for Bio-Pesticide Engineering, Northwest A&F University, Xianyang, China
| | - Yong Wang
- College of Plant Protection, Northwest A&F University, Xianyang, China
- Provincial Center for Bio-Pesticide Engineering, Northwest A&F University, Xianyang, China
| | - He Yan
- College of Plant Protection, Northwest A&F University, Xianyang, China
- Provincial Center for Bio-Pesticide Engineering, Northwest A&F University, Xianyang, China
| | - Juntao Feng
- College of Plant Protection, Northwest A&F University, Xianyang, China
- Provincial Center for Bio-Pesticide Engineering, Northwest A&F University, Xianyang, China
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Takemura C, Senuma W, Tsuzuki M, Terazawa Y, Inoue K, Sato M, Kiba A, Ohnishi K, Kai K, Hikichi Y. The transcription regulator ChpA affects the global transcriptome including quorum sensing-dependent genes in Ralstonia pseudosolanacearum strain OE1-1. MOLECULAR PLANT PATHOLOGY 2023; 24:1370-1384. [PMID: 37452484 PMCID: PMC10576176 DOI: 10.1111/mpp.13374] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/02/2023] [Accepted: 06/26/2023] [Indexed: 07/18/2023]
Abstract
The gram-negative plant-pathogenic β-proteobacterium Ralstonia pseudosolanacearum strain OE1-1 produces methyl 3-hydroxymyristate as a quorum sensing (QS) signal through methyltransferase PhcB and senses the chemical via the sensor histidine kinase PhcS. This leads to activation of the LysR family transcription regulator PhcA, which regulates the genes (QS-dependent genes) responsible for QS-dependent phenotypes, including virulence. The transcription regulator ChpA, which possesses a response regulator receiver domain and also a hybrid sensor histidine kinase/response regulator phosphore-acceptor domain but lacks a DNA-binding domain, is reportedly involved in QS-dependent biofilm formation and virulence of R. pseudosolanacearum strain GMI1000. To explore the function of ChpA in QS of OE1-1, we generated a chpA-deletion mutant (ΔchpA) and revealed that the chpA deletion leads to significantly altered QS-dependent phenotypes. Furthermore, ΔchpA exhibited a loss in its infectivity in xylem vessels of tomato plant roots, losing virulence on tomato plants, similar to the phcA-deletion mutant (ΔphcA). Transcriptome analysis showed that the transcript levels of phcB, phcQ, phcR, and phcA in ΔchpA were comparable to those in OE1-1. However, the transcript levels of 89.9% and 88.9% of positively and negatively QS-dependent genes, respectively, were significantly altered in ΔchpA compared with OE1-1. Furthermore, the transcript levels of these genes in ΔchpA were positively correlated with those in ΔphcA. Together, our results suggest that ChpA is involved in the regulation of these QS-dependent genes, thereby contributing to the behaviour in host plant roots and virulence of OE1-1.
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Affiliation(s)
- Chika Takemura
- Faculty of Agriculture and Marine ScienceKochi UniversityNankokuJapan
- Present address:
Kochi Prefectural Agriculture Research CenterNankokuJapan
| | - Wakana Senuma
- Faculty of Agriculture and Marine ScienceKochi UniversityNankokuJapan
- Present address:
Central Research Institute, Ishihara Sangyo Kaisha, Ltd.KusatsuJapan
| | - Masayuki Tsuzuki
- Faculty of Agriculture and Marine ScienceKochi UniversityNankokuJapan
| | - Yuki Terazawa
- Faculty of Agriculture and Marine ScienceKochi UniversityNankokuJapan
- Present address:
Kumamoto Experimental Station, Sumika Agrotech Co., Ltd.KikuchiJapan
| | - Kanako Inoue
- Research Center for Ultra‐High Voltage Electron MicroscopyOsaka UniversityIbarakiJapan
- Present address:
Division of Biological Sciences Plant Immunity, Nara Institute of Science and TechnologyIkomaJapan
| | - Masanao Sato
- Graduate School of AgricultureHokkaido UniversitySapporoJapan
| | - Akinori Kiba
- Faculty of Agriculture and Marine ScienceKochi UniversityNankokuJapan
| | - Kouhei Ohnishi
- Faculty of Agriculture and Marine ScienceKochi UniversityNankokuJapan
| | - Kenji Kai
- Graduate School of AgricultureOsaka Metropolitan UniversitySakaiJapan
| | - Yasufumi Hikichi
- Faculty of Agriculture and Marine ScienceKochi UniversityNankokuJapan
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15
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Liu Q, Li C, Zhang X, Ding M, Liao X, Yan J, Hu M, Yang L, Wang X, Liao L, Li P, Zhou X. PhcX Is a LqsR-family response regulator that contributes to Ralstonia solanacearum virulence and regulates multiple virulence factors. mBio 2023; 14:e0202823. [PMID: 37787568 PMCID: PMC10653808 DOI: 10.1128/mbio.02028-23] [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: 08/02/2023] [Accepted: 08/15/2023] [Indexed: 10/04/2023] Open
Abstract
IMPORTANCE The bacterial wilt caused by the soil-borne phytopathogen Ralstonia solanacearum is one of the most destructive crop diseases. To achieve a successful infection, R. solanacearum has evolved an intricate regulatory network to orchestrate the expression of an arsenal of virulence factors and fine-tune the allocation of energy. However, despite the wealth of knowledge gained in the past decades, many players and connections are still missing from the network. The importance of our study lies in the identification of PhcX, a novel conserved global regulator with critical roles in modulating the virulence and metabolism of R. solanacearum. PhcX affects many well-characterized regulators and exhibits contrasting modes of regulation from the central regulator PhcA on a variety of virulence-associated traits and genes. Our findings add a valuable piece to the puzzle of how the pathogen regulates its proliferation and infection, which is critical for understanding its pathogenesis and developing disease control strategies.
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Affiliation(s)
- Qingmei Liu
- Guangdong Laboratory for Lingnan Modern Agriculture, Guangdong Province Key Laboratory of Microbial Signals and Disease Control, Integrative Microbiology Research Centre, South China Agricultural University, Guangzhou, China
| | - Chuhao Li
- Guangdong Laboratory for Lingnan Modern Agriculture, Guangdong Province Key Laboratory of Microbial Signals and Disease Control, Integrative Microbiology Research Centre, South China Agricultural University, Guangzhou, China
| | - Xiaohan Zhang
- Guangdong Laboratory for Lingnan Modern Agriculture, Guangdong Province Key Laboratory of Microbial Signals and Disease Control, Integrative Microbiology Research Centre, South China Agricultural University, Guangzhou, China
| | - Mengfan Ding
- Guangdong Laboratory for Lingnan Modern Agriculture, Guangdong Province Key Laboratory of Microbial Signals and Disease Control, Integrative Microbiology Research Centre, South China Agricultural University, Guangzhou, China
| | - Xinyue Liao
- Guangdong Laboratory for Lingnan Modern Agriculture, Guangdong Province Key Laboratory of Microbial Signals and Disease Control, Integrative Microbiology Research Centre, South China Agricultural University, Guangzhou, China
| | - Jinli Yan
- School of Agricultural Science, Xichang University, Xichang, China
| | - Ming Hu
- Guangdong Laboratory for Lingnan Modern Agriculture, Guangdong Province Key Laboratory of Microbial Signals and Disease Control, Integrative Microbiology Research Centre, South China Agricultural University, Guangzhou, China
| | - Leilei Yang
- Guangdong Laboratory for Lingnan Modern Agriculture, Guangdong Province Key Laboratory of Microbial Signals and Disease Control, Integrative Microbiology Research Centre, South China Agricultural University, Guangzhou, China
| | - Xiaoqing Wang
- Guangdong Laboratory for Lingnan Modern Agriculture, Guangdong Province Key Laboratory of Microbial Signals and Disease Control, Integrative Microbiology Research Centre, South China Agricultural University, Guangzhou, China
| | - Lisheng Liao
- Guangdong Laboratory for Lingnan Modern Agriculture, Guangdong Province Key Laboratory of Microbial Signals and Disease Control, Integrative Microbiology Research Centre, South China Agricultural University, Guangzhou, China
| | - Peng Li
- Ministry of Education Key Laboratory for Ecology of Tropical Islands, Hainan Provincial Key Laboratory for Tropical Plant and Animal Ecology, College of Life Sciences, Hainan Normal University, Haikou, China
| | - Xiaofan Zhou
- Guangdong Laboratory for Lingnan Modern Agriculture, Guangdong Province Key Laboratory of Microbial Signals and Disease Control, Integrative Microbiology Research Centre, South China Agricultural University, Guangzhou, China
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Liu S, Xue Q, Zhu S, Liu Y, Zou H. Ralstonia solanacearum Suppresses Tomato Root Growth by Downregulation of a Wall-Associated Receptor Kinase. PLANTS (BASEL, SWITZERLAND) 2023; 12:3600. [PMID: 37896064 PMCID: PMC10610323 DOI: 10.3390/plants12203600] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/24/2023] [Revised: 10/06/2023] [Accepted: 10/13/2023] [Indexed: 10/29/2023]
Abstract
The root architecture of a range of host plants is altered in response to Ralstonia solanacearum infection. This work aimed to identify host genes involved in root development during R. solanacearum infection. A deficient mutant of the type III secretion system regulator hrpB was created in R. solanacearum GMI1000. The hrpB mutant was impaired in virulence but showed a similar suppressive effect as wild-type GMI1000 on tomato root development. Based on comparative transcriptome analysis, 209 genes were found that showed the same changed expression pattern in GMI1000 and hrpB mutant infected roots relative to uninoculated roots. Among them, the wall-associated receptor kinase WAKL20 was substantially downregulated in GMI1000 and hrpB mutant infected roots. Knockdown of WAKL20 led to a shorter primary root length and fewer lateral roots in tomato as well as in Nicotiana benthamiana. The WAKL20 is a pivotal target suppressed by R. solanacearum to shape the altered root development during infection.
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Affiliation(s)
| | | | | | | | - Huasong Zou
- School of Life Sciences and Health, Huzhou College, Huzhou 313000, China; (S.L.); (Q.X.); (S.Z.); (Y.L.)
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17
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Lee HJ, Lee SM, Choi M, Kwon JH, Lee SW. A Mutation of a Putative NDP-Sugar Epimerase Gene in Ralstonia pseudosolanacearum Attenuates Exopolysaccharide Production and Bacterial Virulence in Tomato Plant. THE PLANT PATHOLOGY JOURNAL 2023; 39:417-429. [PMID: 37817490 PMCID: PMC10580051 DOI: 10.5423/ppj.oa.06.2023.0090] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/29/2023] [Revised: 08/18/2023] [Accepted: 08/21/2023] [Indexed: 10/12/2023]
Abstract
Ralstonia solanacearum species complex (RSSC) is a soil borne plant pathogen causing bacterial wilt on various important crops, including Solanaceae plants. The bacterial pathogens within the RSSC produce exopolysaccharide (EPS), a highly complicated nitrogen-containing heteropolymeric polysaccharide, as a major virulence factor. However, the biosynthetic pathway of the EPS in the RSSC has not been fully characterized. To identify genes in EPS production beyond the EPS biosynthetic gene operon, we selected the EPS-defective mutants of R. pseudosolanacearum strain SL341 from Tn5-inserted mutant pool. Among several EPS-defective mutants, we identified a mutant, SL341P4, with a Tn5-insertion in a gene encoding a putative NDP-sugar epimerase, a putative membrane protein with sugar-modifying moiety, in a reverse orientation to EPS biosynthesis gene cluster. This protein showed similar to other NDP-sugar epimerases involved in EPS biosynthesis in many phytopathogens. Mutation of the NDP-sugar epimerase gene reduced EPS production and biofilm formation in R. pseudosolanacearum. Additionally, the SL341P4 mutant exhibited reduced disease severity and incidence of bacterial wilt in tomato plants compared to the wild-type SL341 without alteration of bacterial multiplication. These results indicate that the NDP-sugar epimerase gene is required for EPS production and bacterial virulence in R. pseudosolanacearum.
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Affiliation(s)
- Hyoung Ju Lee
- Department of Applied Bioscience, Dong-A University, Busan 49315, Korea
| | - Sang-Moo Lee
- Institute of Agricultural Life Sciences, Dong-A University, Busan 49315, Korea
| | - Minseo Choi
- Department of Applied Bioscience, Dong-A University, Busan 49315, Korea
| | - Joo Hwan Kwon
- Department of Applied Bioscience, Dong-A University, Busan 49315, Korea
| | - Seon-Woo Lee
- Department of Applied Bioscience, Dong-A University, Busan 49315, Korea
- Institute of Agricultural Life Sciences, Dong-A University, Busan 49315, Korea
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Wang S, Hu M, Chen H, Li C, Xue Y, Song X, Qi Y, Liu F, Zhou X, Zhang LH, Zhou J. Pseudomonas forestsoilum sp. nov. and P. tohonis biocontrol bacterial wilt by quenching 3-hydroxypalmitic acid methyl ester. FRONTIERS IN PLANT SCIENCE 2023; 14:1193297. [PMID: 37457350 PMCID: PMC10349395 DOI: 10.3389/fpls.2023.1193297] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 03/24/2023] [Accepted: 06/19/2023] [Indexed: 07/18/2023]
Abstract
Bacterial wilt caused by Ralstonia solanacearum ranks the second top important bacterial plant disease worldwide. It is also the most important bacterial disease threatening the healthy development of Casuarina equisetifolia protection forest. 3-hydroxypalmitic acid methyl ester (3-OH PAME) functions as an important quorum sensing (QS) signal regulating the expression of virulence genes in R. solanacearum, and has been regarded as an ideal target for disease prevention and control. To screen native microorganisms capable of degrading 3-OH PAME, samples of C. equisetifolia branches and forest soil were collected and cultured in the medium containing 3-OH PAME as the sole carbon source. Bacteria with over 85% degradation rates of 3-OH PAME after 7-day incubation were further separated and purified. As a result, strain Q1-7 isolated from forest soil and strain Q4-3 isolated from C. equisetifolia branches were obtained and identified as Pseudomonas novel species Pseudomonas forestsoilum sp. nov. and P. tohonis, respectively, according to whole genome sequencing results. The degradation efficiencies of 3-OH PAME of strains Q1-7 and Q4-3 were 95.80% and 100.00% at 48 h, respectively. Both strains showed high esterase activities and inhibited R. solanacearum exopolysaccharide (EPS) and cellulase production. Application of strains Q1-7 and Q4-3 effectively protects C. equisetifolia, peanut and tomato plants from infection by R. solanacearum. Findings in this study provide potential resources for the prevention and control of bacterial wilt caused by R. solanacearum, as well as valuable materials for the identification of downstream quenching genes and the research and development of quenching enzymes for disease control.
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19
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Gu M, Wang Q, Fan R, Liu S, Zhu F, Feng G, Zhang J. Isolation, Characterization and Antibacterial Activity of 4-Allylbenzene-1,2-diol from Piper austrosinense. Molecules 2023; 28:molecules28083572. [PMID: 37110806 PMCID: PMC10146670 DOI: 10.3390/molecules28083572] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2023] [Revised: 04/15/2023] [Accepted: 04/16/2023] [Indexed: 04/29/2023] Open
Abstract
Isolation for antibacterial compounds from natural plants is a promising approach to develop new pesticides. In this study, two compounds were obtained from the Chinese endemic plant Piper austrosinense using bioassay-guided fractionation. Based on analyses of 1H-NMR, 13C-NMR, and mass spectral data, the isolated compounds were identified as 4-allylbenzene-1,2-diol and (S)-4-allyl-5-(1-(3,4-dihydroxyphenyl)allyl)benzene-1,2-diol. 4-Allylbenzene-1,2-diol was shown to have strong antibacterial activity against four plant pathogens, including Xanthomonas oryzae pathovar oryzae (Xoo), X. axonopodis pv. citri (Xac), X. oryzae pv. oryzicola (Xoc) and X. campestris pv. mangiferaeindicae (Xcm). Further bioassay results exhibited that 4-allylbenzene-1,2-diol had a broad antibacterial spectrum, including Xoo, Xac, Xoc, Xcm, X. fragariae (Xf), X. campestris pv. campestris (Xcc), Pectobacterium carotovorum subspecies brasiliense (Pcb) and P. carotovorum subsp. carotovorum (Pcc), with minimum inhibitory concentration (MIC) values ranging from 333.75 to 1335 μmol/L. The pot experiment showed that 4-allylbenzene-1,2-diol exerted an excellent protective effect against Xoo, with a controlled efficacy reaching 72.73% at 4 MIC, which was superior to the positive control kasugamycin (53.03%) at 4 MIC. Further results demonstrated that the 4-allylbenzene-1,2-diol damaged the integrity of the cell membrane and increased cell membrane permeability. In addition, 4-allylbenzene-1,2-diol also prevented the pathogenicity-related biofilm formation in Xoo, thus limiting the movement of Xoo and reducing the production of extracellular polysaccharides (EPS) in Xoo. These findings suggest the value of 4-allylbenzene-1,2-diol and P. austrosinense could be as promising resources for developing novel antibacterial agents.
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Affiliation(s)
- Mengxuan Gu
- National Key Laboratory of Green Pesticide, Key Laboratory of Green Pesticide and Agricultural Bioengineering, Ministry of Education, Center for R&D of Fine Chemicals of Guizhou University, Guiyang 550025, China
- Environment and Plant Protection Institute, Chinese Academy of Tropical Agricultural Science, Haikou 571101, China
| | - Qin Wang
- Environment and Plant Protection Institute, Chinese Academy of Tropical Agricultural Science, Haikou 571101, China
| | - Rui Fan
- Spice and Beverage Research Institute, Chinese Academy of Tropical Agricultural Sciences (CATAS), Wanning 571533, China
| | - Shoubai Liu
- Key Laboratory of Genetics and Germplasm Innovation of Tropical Special Forest Trees and Ornamental Plants, Ministry of Education, Hainan Key Laboratory for Biology of Tropical Specific Ornamental Plants Germplasm, School of Forestry, Hainan University, Haikou 570228, China
| | - Fadi Zhu
- Environment and Plant Protection Institute, Chinese Academy of Tropical Agricultural Science, Haikou 571101, China
| | - Gang Feng
- Environment and Plant Protection Institute, Chinese Academy of Tropical Agricultural Science, Haikou 571101, China
| | - Jing Zhang
- Environment and Plant Protection Institute, Chinese Academy of Tropical Agricultural Science, Haikou 571101, China
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Dominelli N, Regaiolo A, Willy L, Heermann R. Interkingdom Signaling of the Insect Pathogen Photorhabdus luminescens with Plants Via the LuxR solo SdiA. Microorganisms 2023; 11:microorganisms11040890. [PMID: 37110313 PMCID: PMC10143992 DOI: 10.3390/microorganisms11040890] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2023] [Revised: 03/24/2023] [Accepted: 03/27/2023] [Indexed: 03/31/2023] Open
Abstract
In bacteria, group-coordinated behavior such as biofilm formation or virulence are often mediated via cell–cell communication, a process referred to as quorum sensing (QS). The canonical QS system of Gram-negative bacteria uses N-acyl homoserine lactones (AHLs) as communication molecules, which are produced by LuxI-type synthases and sensed by cognate LuxR-type receptors. These receptors act as transcriptional regulators controlling the expression of specific genes. Some bacteria harbor LuxR-type receptors lacking a cognate LuxI-type synthases, designated as LuxR solos. Among many other LuxR solos, the entomopathogenic enteric bacterium Photorhabdus luminescens harbors a SdiA-like LuxR solo containing an AHL signal-binding domain, for which a respective signal molecule and target genes have not been identified yet. Here we performed SPR analysis to demonstrate that SdiA acts as a bidirectional regulator of transcription, tightly controlling its own expression and the adjacent PluDJC_01670 (aidA) gene in P. luminescens, a gene supposed to be involved in the colonization of eukaryotes. Via qPCR we could further determine that in sdiA deletion mutant strains, aidA is upregulated, indicating that SdiA negatively affects expression of aidA. Furthermore, the ΔsdiA deletion mutant exhibited differences in biofilm formation and motility compared with the wild-type. Finally, using nanoDSF analysis we could identify putative binding ability of SdiA towards diverse AHLs, but also to plant-derived signals, modulating the DNA-binding capacity of SdiA, suggesting that this LuxR solo acts as an important player in interkingdom signaling between P. luminescens and plants.
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Cell Density-Regulated Adhesins Contribute to Early Disease Development and Adhesion in Ralstonia solanacearum. Appl Environ Microbiol 2023; 89:e0156522. [PMID: 36688670 PMCID: PMC9973027 DOI: 10.1128/aem.01565-22] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023] Open
Abstract
Adhesins (adhesive proteins) help bacteria stick to and colonize diverse surfaces and often contribute to virulence. The genome of the bacterial wilt pathogen Ralstonia solanacearum (Rs) encodes dozens of putative adhesins, some of which are upregulated during plant pathogenesis. Little is known about the role of these proteins in bacterial wilt disease. During tomato colonization, three putative Rs adhesin genes were upregulated in a ΔphcA quorum-sensing mutant that cannot respond to high cell densities: radA (Ralstonia adhesin A), rcpA (Ralstonia collagen-like protein A), and rcpB. Based on this differential gene expression, we hypothesized that adhesins repressed by PhcA contribute to early disease stages when Rs experiences a low cell density. During root colonization, Rs upregulated rcpA and rcpB, but not radA, relative to bacteria in the stem at mid-disease. Root attachment assays and confocal microscopy with ΔrcpA/B and ΔradA revealed that all three adhesins help Rs attach to tomato seedling roots. Biofilm assays on abiotic surfaces found that Rs does not require RadA, RcpA, or RcpB for interbacterial attachment (cohesion), but these proteins are essential for anchoring aggregates to a surface (adhesion). However, Rs did not require the adhesins for later disease stages in planta, including colonization of the root endosphere and stems. Interestingly, all three adhesins were essential for full competitive fitness in planta. Together, these infection stage-specific assays identified three proteins that contribute to adhesion and the critical first host-pathogen interaction in bacterial wilt disease. IMPORTANCE Every microbe must balance its need to attach to surfaces with the biological imperative to move and spread. The high-impact plant-pathogenic bacterium Ralstonia solanacearum can stick to biotic and abiotic substrates, presumably using some of the dozens of putative adhesins encoded in its genome. We confirmed the functions and identified the biological roles of multiple afimbrial adhesins. By assaying the competitive fitness and the success of adhesin mutants in three different plant compartments, we identified the specific disease stages and host tissues where three previously cryptic adhesins contribute to success in plants. Combined with tissue-specific regulatory data, this work indicates that R. solanacearum deploys distinct adhesins that help it succeed at different stages of plant pathogenesis.
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Inoue K, Takemura C, Senuma W, Maeda H, Kai K, Kiba A, Ohnishi K, Tsuzuki M, Hikichi Y. The behavior of Ralstonia pseudosolanacearum strain OE1-1 and morphological changes of cells in tomato roots. JOURNAL OF PLANT RESEARCH 2023; 136:19-31. [PMID: 36427093 DOI: 10.1007/s10265-022-01427-3] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/05/2022] [Accepted: 11/14/2022] [Indexed: 06/16/2023]
Abstract
The soil-borne Gram-negative β-proteobacterium Ralstonia solanacearum species complex (RSSC) infects tomato roots through the wounds where secondary roots emerge, infecting xylem vessels. Because it is difficult to observe the behavior of RSSC by a fluorescence-based microscopic approach at high magnification, we have little information on its behavior at the root apexes in tomato roots. To analyze the infection route of a strain of phylotype I of RSSC, R. pseudosolanacearum strain OE1-1, which invades tomato roots through the root apexes, we first developed an in vitro pathosystem using 4 day-old-tomato seedlings without secondary roots co-incubated with the strain OE1-1. The microscopic observation of toluidine blue-stained longitudinal semi-thin resin sections of tomato roots allowed to detect attachment of the strain OE1-1 to surfaces of the meristematic and elongation zones in tomato roots. We then observed colonization of OE1-1 in intercellular spaces between epidermis and cortex in the elongation zone, and a detached epidermis in the elongation zone. Furthermore, we observed cortical and endodermal cells without a nucleus and with the cell membrane pulling away from the cell wall. The strain OE1-1 next invaded cell wall-degenerated cortical cells and formed mushroom-shaped biofilms to progress through intercellular spaces of the cortex and endodermis, infecting pericycle cells and xylem vessels. The deletion of egl encoding β-1,4-endoglucanase, which is one of quorum sensing (QS)-inducible plant cell wall-degrading enzymes (PCDWEs) secreted via the type II secretion system (T2SS) led to a reduced infectivity in cortical cells. Furthermore, the QS-deficient and T2SS-deficient mutants lost their infectivity in cortical cells and the following infection in xylem vessels. Taking together, infection of OE1-1, which attaches to surfaces of the meristematic and elongation zones, in cortical cells of the elongation zone in tomato roots, dependently on QS-inducible PCDWEs secreted via the T2SS, leads to its subsequent infection in xylem vessels.
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Affiliation(s)
- Kanako Inoue
- Research Center for Ultra-High Voltage Electron Microscopy, Osaka University, Ibaraki, Japan
| | - Chika Takemura
- Faculty of Agriculture and Marine Science, Kochi University, 783-8502, Nankoku, Kochi, Japan
| | - Wakana Senuma
- Faculty of Agriculture and Marine Science, Kochi University, 783-8502, Nankoku, Kochi, Japan
| | - Hidefumi Maeda
- Faculty of Advanced Science and Technology, Ryukoku University, Otsu, Japan
| | - Kenji Kai
- Graduate School of Agriculture, Osaka Metropolitan University, Sakai, Japan
| | - Akinori Kiba
- Faculty of Agriculture and Marine Science, Kochi University, 783-8502, Nankoku, Kochi, Japan
| | - Kouhei Ohnishi
- Faculty of Agriculture and Marine Science, Kochi University, 783-8502, Nankoku, Kochi, Japan
| | - Masayuki Tsuzuki
- Faculty of Agriculture and Marine Science, Kochi University, 783-8502, Nankoku, Kochi, Japan
| | - Yasufumi Hikichi
- Faculty of Agriculture and Marine Science, Kochi University, 783-8502, Nankoku, Kochi, Japan.
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In through the Out Door: A Functional Virulence Factor Secretion System Is Necessary for Phage Infection in Ralstonia solanacearum. mBio 2022; 13:e0147522. [PMID: 36314808 PMCID: PMC9765573 DOI: 10.1128/mbio.01475-22] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/27/2023] Open
Abstract
Bacteriophages put intense selective pressure on microbes, which must evolve diverse resistance mechanisms to survive continuous phage attacks. We used a library of spontaneous Bacteriophage Insensitive Mutants (BIMs) to learn how the plant pathogen Ralstonia solanacearum resists the virulent lytic podophage phiAP1. Phenotypic and genetic characterization of many BIMs suggested that the R. solanacearum Type II Secretion System (T2SS) plays a key role in phiAP1 infection. Using precision engineered mutations that permit T2SS assembly but either inactivate the T2SS GspE ATPase or sterically block the secretion portal, we demonstrated that phiAP1 needs a functional T2SS to infect R. solanacearum. This distinction between the static presence of T2SS components, which is necessary but not sufficient for phage sensitivity, and the energized and functional T2SS, which is sufficient, implies that binding interactions alone cannot explain the role of the T2SS in phiAP1 infection. Rather, our results imply that some aspect of the resetting of the T2SS, such as disassembly of the pseudopilus, is required. Because R. solanacearum secretes multiple virulence factors via the T2SS, acquiring resistance to phiAP1 also dramatically reduced R. solanacearum virulence on tomato plants. This acute fitness trade-off suggests this group of phages may be a sustainable control strategy for an important crop disease. IMPORTANCE Ralstonia solanacearum is a destructive plant pathogen that causes lethal bacterial wilt disease in hundreds of diverse plant hosts, including many economically important crops. Phages that kill R. solanacearum could offer effective and environmentally friendly wilt disease control, but only if the bacterium cannot easily evolve resistance. Encouragingly, most R. solanacearum mutants resistant to the virulent lytic phage phiAP1 no longer secreted multiple virulence factors and had much reduced fitness and virulence on tomato plants. Further analysis revealed that phage phiAP1 needs a functional type II secretion system to infect R. solanacearum, suggesting this podophage uses a novel infection mechanism.
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Eisfeld C, Schijven JF, Kastelein P, van Breukelen BM, Medema G, Velstra J, Teunis PFM, van der Wolf JM. Dose-response relationship of Ralstonia solanacearum and potato in greenhouse and in vitro experiments. FRONTIERS IN PLANT SCIENCE 2022; 13:1074192. [PMID: 36937141 PMCID: PMC10020725 DOI: 10.3389/fpls.2022.1074192] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/19/2022] [Accepted: 11/29/2022] [Indexed: 06/18/2023]
Abstract
Ralstonia solanacearum is the causative agent of bacterial wilt of potato and other vegetable crops. Contaminated irrigation water contributes to the dissemination of this pathogen but the exact concentration or biological threshold to cause an infection is unknown. In two greenhouse experiments, potted potato plants (Solanum tuberosum) were exposed to a single irrigation with 50 mL water (non-invasive soil-soak inoculation) containing no or 102 - 108 CFU/mL R. solanacearum. The disease response of two cultivars, Kondor and HB, were compared. Disease development was monitored over a three-month period after which stems, roots and tubers of asymptomatic plants were analyzed for latent infections. First wilting symptoms were observed 15 days post inoculation in a plant inoculated with 5x109 CFU and a mean disease index was used to monitor disease development over time. An inoculum of 5x105 CFU per pot (1.3x102 CFU/g soil) was the minimum dose required to cause wilting symptoms, while one latent infection was detected at the lowest dose of 5x102 CFU per pot (0.13 CFU/g). In a second set of experiments, stem-inoculated potato plants grown in vitro were used to investigate the dose-response relationship under optimal conditions for pathogen growth and disease development. Plants were inoculated with doses between 0.5 and 5x105 CFU/plant which resulted in visible symptoms at all doses. The results led to a dose-response model describing the relationship between R. solanacearum exposure and probability of infection or illness of potato plants. Cultivar Kondor was more susceptible to brown-rot infections than HB in greenhouse experiments while there was no significant difference between the dose-response models of both cultivars in in vitro experiments. The ED50 for infection of cv Kondor was 1.1x107 CFU. Results can be used in management strategies aimed to reduce or eliminate the risk of bacterial wilt infection when using treated water in irrigation.
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Affiliation(s)
- Carina Eisfeld
- Department of Water Management, Faculty of Civil Engineering and Geosciences, Delft University of Technology, Delft, Netherlands
| | - Jack F. Schijven
- Department of Statistics, Informatics and Modelling, National Institute of Public Health and the Environment, Bilthoven, Netherlands
- Department of Earth Sciences, Faculty of Geosciences, Utrecht University, Utrecht, Netherlands
| | - Pieter Kastelein
- Department of Biointeractions and Plant Health, Wageningen Plant Research, Wageningen, Netherlands
| | - Boris M. van Breukelen
- Department of Water Management, Faculty of Civil Engineering and Geosciences, Delft University of Technology, Delft, Netherlands
| | - Gertjan Medema
- Department of Water Management, Faculty of Civil Engineering and Geosciences, Delft University of Technology, Delft, Netherlands
- Water Quality & Health, KWR Water Research Institute, Nieuwegein, Netherlands
| | | | - Peter F. M. Teunis
- Center for Global Safe Water, Sanitation and Health, Hubert Department of Global Health Rollins School of Public Health Emory University, Atlanta, GA, United States
| | - Jan M. van der Wolf
- Department of Biointeractions and Plant Health, Wageningen Plant Research, Wageningen, Netherlands
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Rivera-Zuluaga K, Hiles R, Barua P, Caldwell D, Iyer-Pascuzzi AS. Getting to the root of Ralstonia invasion. Semin Cell Dev Biol 2022; 148-149:3-12. [PMID: 36526528 DOI: 10.1016/j.semcdb.2022.12.002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2022] [Revised: 12/01/2022] [Accepted: 12/05/2022] [Indexed: 12/16/2022]
Abstract
Plant diseases caused by soilborne pathogens are a major limiting factor in crop production. Bacterial wilt disease, caused by soilborne bacteria in the Ralstonia solanacearum Species Complex (Ralstonia), results in significant crop loss throughout the world. Ralstonia invades root systems and colonizes plant xylem, changing plant physiology and ultimately causing plant wilting in susceptible varieties. Elucidating how Ralstonia invades and colonizes plants is central to developing strategies for crop protection. Here we review Ralstonia pathogenesis from root detection and attachment, early root colonization, xylem invasion and subsequent wilting. We focus primarily on studies in tomato from the last 5-10 years. Recent work has identified elegant mechanisms Ralstonia uses to adapt to the plant xylem, and has discovered new genes that function in Ralstonia fitness in planta. A picture is emerging of an amazingly versatile pathogen that uses multiple strategies to make its surrounding environment more hospitable and can adapt to new environments.
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Abstract
Hereditary symbioses have the potential to drive transgenerational effects, yet the mechanisms responsible for transmission of heritable plant symbionts are still poorly understood. The leaf symbiosis between Dioscorea sansibarensis and the bacterium Orrella dioscoreae offers an appealing model system to study how heritable bacteria are transmitted to the next generation. Here, we demonstrate that inoculation of apical buds with a bacterial suspension is sufficient to colonize newly formed leaves and propagules, and to ensure transmission to the next plant generation. Flagellar motility is not required for movement inside the plant but is important for the colonization of new hosts. Further, tissue-specific regulation of putative symbiotic functions highlights the presence of two distinct subpopulations of bacteria in the leaf gland and at the shoot meristem. We propose that bacteria in the leaf gland dedicate resources to symbiotic functions, while dividing bacteria in the shoot tip ensure successful colonization of meristematic tissue, glands, and propagules. Compartmentalization of intrahost populations together with tissue-specific regulation may serve as a robust mechanism for the maintenance of mutualism in leaf symbiosis.
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De La Fuente L, Merfa MV, Cobine PA, Coleman JJ. Pathogen Adaptation to the Xylem Environment. ANNUAL REVIEW OF PHYTOPATHOLOGY 2022; 60:163-186. [PMID: 35472277 DOI: 10.1146/annurev-phyto-021021-041716] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
A group of aggressive pathogens have evolved to colonize the plant xylem. In this vascular tissue, where water and nutrients are transported from the roots to the rest of the plant, pathogens must be able to thrive under acropetal xylem sap flow and scarcity of nutrients while having direct contact only with predominantly dead cells. Nevertheless, a few bacteria have adapted to exclusively live in the xylem, and various pathogens may colonize other plant niches without causing symptoms unless they reach the xylem. Once established, the pathogens modulate its physicochemical conditions to enhance their growth and virulence. Adaptation to the restrictive lifestyle of the xylem leads to genome reduction in xylem-restricted bacteria, as they have a higher proportion of pseudogenes in their genome. The basis of xylem adaptation is not completely understood; therefore, a need still exists for model systems to advance the knowledge on this topic.
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Affiliation(s)
- Leonardo De La Fuente
- Department of Entomology and Plant Pathology, Auburn University, Auburn, Alabama, USA;
| | - Marcus V Merfa
- Department of Entomology and Plant Pathology, Auburn University, Auburn, Alabama, USA;
| | - Paul A Cobine
- Department of Biological Sciences, Auburn University, Auburn, Alabama, USA
| | - Jeffrey J Coleman
- Department of Entomology and Plant Pathology, Auburn University, Auburn, Alabama, USA;
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RasI/R Quorum Sensing System Controls the Virulence of Ralstonia solanacearum Strain EP1. Appl Environ Microbiol 2022; 88:e0032522. [PMID: 35876567 PMCID: PMC9361817 DOI: 10.1128/aem.00325-22] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023] Open
Abstract
Quorum sensing (QS) is a widely conserved bacterial regulatory mechanism that relies on production and perception of autoinducing chemical signals to coordinate diverse cooperative activities, such as virulence, exoenzyme secretion, and biofilm formation. In Ralstonia solanacearum, a phytopathogen causing severe bacterial wilt diseases in many plant species, previous studies identified the PhcBSR QS system, which plays a key role in regulation of its physiology and virulence. In this study, we found that R. solanacearum strain EP1 contains the genes encoding uncharacterized LuxI/LuxR (LuxI/R) QS homologues (RasI/RasR [designated RasI/R here]). To determine the roles of the RasI/R system in strain EP1, we constructed a specific reporter for the signals catalyzed by RasI. Chromatography separation and structural analysis showed that RasI synthesized primarily N-(3-hydroxydodecanoyl)-homoserine lactone (3-OH-C12-HSL). In addition, we showed that the transcriptional expression of rasI is regulated by RasR in response to 3-OH-C12-HSL. Phenotype analysis unveiled that the RasI/R system plays a critical role in modulation of cellulase production, motility, biofilm formation, oxidative stress response, and virulence of R. solanacearum EP1. We then further characterized this system by determining the RasI/R regulon using transcriptome sequencing (RNA-seq) analysis, which showed that this newly identified QS system regulates the transcriptional expression of over 154 genes associated with bacterial physiology and pathogenic properties. Taken together, the findings from this study present an essential new QS system in regulation of R. solanacearum physiology and virulence and provide new insight into the complicated regulatory mechanisms and networks in this important plant pathogen. IMPORTANCE Quorum sensing (QS) is a key regulator of virulence factors in many plant-pathogenic bacteria. Previous studies unveiled two QS systems (i.e., PhcBSR and SolI/R) in several R. solanacearum strains. The PhcBSR QS system is known for its key roles in regulation of bacterial virulence, and the LuxI/LuxR (SolI/R) QS system appears dispensable for pathogenicity in a number of R. solanacearum strains. In this study, a new functional QS system (i.e., RasI/R) was identified and characterized in R. solanacearum strain EP1 isolated from infected eggplants. Phenotype analyses showed that the RasI/R system plays an important role in regulation of a range of biological activities associated with bacterial virulence. This QS system produces and responds to the QS signal 3-OH-C12-HSL and hence regulates critical bacterial abilities in survival and infection. To date, multiple QS signaling circuits in R. solanacearum strains are still not well understood. Our findings from this study provide new insight into the complicated QS regulatory networks that govern the physiology and virulence of R. solanacearum and present a valid target and clues for the control and prevention of bacterial wilt diseases.
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Lipid-rich endo-metabolites from a vertically transmitted fungal endophyte Penicillium sp. PM031 attenuate virulence factors of phytopathogenic Ralstonia solanacearum. Microbiol Res 2022; 261:127058. [DOI: 10.1016/j.micres.2022.127058] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2021] [Revised: 04/15/2022] [Accepted: 05/01/2022] [Indexed: 11/19/2022]
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Ray JD, Subandiyah S, Prakoso AB, Rincón-Flórez VA, Carvalhais LC, Drenth A. Transmission of Blood Disease in Banana. PLANT DISEASE 2022; 106:2155-2164. [PMID: 35077223 DOI: 10.1094/pdis-10-21-2373-re] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
Banana Blood disease is a bacterial wilt caused by Ralstonia syzygii subsp. celebesensis and is an economically important disease in Indonesia and Malaysia. Transmission of this pathogen is hypothesized to occur through insects mechanically transferring bacteria from diseased to healthy banana inflorescences and other pathways involving pruning tools, water movement, and root-to-root contact. This study demonstrates that the ooze from the infected male bell and the sap from various symptomatic plant parts are infective, and the cut surfaces of a bunch peduncle, petiole, corm, pseudostem, and the rachis act as infection courts for R. syzygii subsp. celebesensis. In addition, evidence is provided that R. syzygii subsp. celebesensis is highly tool transmissible, that the bacterium can be transferred from the roots of a diseased plant to the roots of a healthy plant and transferred from the mother plant to the sucker. We provide evidence that local dispersal of Blood disease occurs predominantly through mechanical transmission by insects, birds, bats, or human activities from diseased to healthy banana plants and that long-distance dispersal occurs through the movement of contaminated planting material. Disease management strategies to prevent crop losses associated with this emerging disease are discussed based on our findings.
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Affiliation(s)
- Jane D Ray
- Centre for Horticultural Science, The University of Queensland, Brisbane 4001, Australia
| | - Siti Subandiyah
- Research Center for Biotechnology, Universitas Gadjah Mada, Yogyakarta 55281, Indonesia
- Department of Entomology and Plant Pathology, Universitas Gadjah Mada, Yogyakarta 55281, Indonesia
| | - Ady B Prakoso
- Department of Entomology and Plant Pathology, Universitas Gadjah Mada, Yogyakarta 55281, Indonesia
| | - Vivian A Rincón-Flórez
- Centre for Horticultural Science, The University of Queensland, Brisbane 4001, Australia
| | - Lilia C Carvalhais
- Centre for Horticultural Science, The University of Queensland, Brisbane 4001, Australia
| | - André Drenth
- Centre for Horticultural Science, The University of Queensland, Brisbane 4001, Australia
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Silicon Controls Bacterial Wilt Disease in Tomato Plants and Inhibits the Virulence-Related Gene Expression of Ralstonia solanacearum. Int J Mol Sci 2022; 23:ijms23136965. [PMID: 35805970 PMCID: PMC9266643 DOI: 10.3390/ijms23136965] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2022] [Revised: 05/26/2022] [Accepted: 06/21/2022] [Indexed: 02/01/2023] Open
Abstract
Silicon (Si) has a multifunctional role in improving plant growth and enhancing plant disease resistance, but its mechanisms are not fully understood. In this study, we investigated the impacts of silicon application on the control of bacterial wilt and elucidated the molecular mechanisms using transcriptome sequencing. Compared to non-Si treatment, Si application (0.5–2 mM) significantly reduces tomato bacterial wilt index by 46.31–72.23%. However, Si does not influence the growth of R. solanacearum. Si application negatively influences R. solanacearum exopolysaccharide (EPS) synthesis and biofilm formation. Transcriptome analysis showed that Si treatment significantly downregulates the expression of virulence genes’ transcriptional regulator (xpsR), EPS synthesis-related genes (epsD and tek), and type III effectors (HrpB2, SpaO, and EscR) in R. solanacearum. In addition, Si remarkably upregulates the expression of twitch motor-related genes (pilE2, pilE, fimT, and PilX). These findings suggest that silicon-suppressed tomato wilt incidence may be due to the regulation of the virulence-related genes of R. solanacearum by Si. Our research adds new knowledge to the application of Si in the field of disease control.
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Liu Y, Tan X, Pan Y, Yu J, Du Y, Liu X, Ding W. Mutation in phcA Enhanced the Adaptation of Ralstonia solanacearum to Long-Term Acid Stress. Front Microbiol 2022; 13:829719. [PMID: 35722283 PMCID: PMC9204249 DOI: 10.3389/fmicb.2022.829719] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2021] [Accepted: 05/03/2022] [Indexed: 11/13/2022] Open
Abstract
Bacterial wilt, caused by the plant pathogen Ralstonia solanacearum, occurs more severely in acidified soil according to previous reports. However, R. solanacearum cannot grow well in acidic environments under barren nutrient culture conditions, especially when the pH is lower than 5. With the worsening acidification of farmland, further determination of how R. solanacearum adapts to the long-term acidic environment is worthwhile. In this study, experimental evolution was applied to evaluate the adaptability and mechanism of the R. solanacearum experimental population responding to long-term acid stress. We chose the CQPS-1 strain as the ancestor, and minimal medium (MM medium) with different pH values as the culture environment to simulate poor soil. After 1500 generations of serial passage experiments in pH 4.9 MM, acid-adapted experimental strains (denoted as C49 strains) were obtained, showing significantly higher growth rates than the growth rates of control experimental strains (serial passage experiment in pH 6.5 MM, denoted as C65 strains). Competition experiments showed that the competitive indices (CIs) of all selected clones from C49 strains were superior to the ancestor in acidic environment competitiveness. Based on the genome variation analysis and functional verification, we confirmed that loss of function in the phcA gene was associated with the acid fitness gain of R. solanacearum, which meant that the inactivation of the PhcA regulator caused by gene mutation mediated the population expansion of R. solanacearum when growing in an acidic stress environment. Moreover, the swimming motility of acid evolution strains and the phcA deletion mutant was significantly enhanced compared to CQPS-1. This work provided evidence for understanding the adaptive strategy of R. solanacearum to the long-term acidic environment.
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Affiliation(s)
- Ying Liu
- College of Plant Protection, Southwest University, Chongqing, China
| | - Xi Tan
- College of Plant Protection, Southwest University, Chongqing, China
| | - Yanxin Pan
- College of Plant Protection, Southwest University, Chongqing, China
| | - Jiamin Yu
- Sichuan Company of China National Tobacco Corporation, Chengdu, China
| | - Yiran Du
- College of Plant Protection, Southwest University, Chongqing, China
| | - Xiaojiao Liu
- College of Plant Protection, Southwest University, Chongqing, China
| | - Wei Ding
- College of Plant Protection, Southwest University, Chongqing, China
- *Correspondence: Wei Ding,
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Ye P, Li X, Cui B, Song S, Shen F, Chen X, Wang G, Zhou X, Deng Y. Proline utilization A controls bacterial pathogenicity by sensing its substrate and cofactors. Commun Biol 2022; 5:496. [PMID: 35614320 PMCID: PMC9132996 DOI: 10.1038/s42003-022-03451-4] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2021] [Accepted: 05/05/2022] [Indexed: 11/26/2022] Open
Abstract
Previous reports indicate that proline utilization A (PutA) is involved in the oxidation of proline to glutamate in many bacteria. We demonstrate here that in addition to its role in proline catabolism, PutA acts as a global regulator to control the important biological functions and virulence of Ralstonia solanacearum. PutA regulates target gene expression levels by directly binding to promoter DNA, and its regulatory activity is enhanced by L-proline. Intriguingly, we reveal that the cofactors NAD+ and FAD boost the enzymatic activity of PutA for converting L-proline to L-glutamic acid but inhibit the regulatory activity of PutA for controlling target gene expression. Our results present evidence that PutA is a proline metabolic enzyme that also functions as a global transcriptional regulator in response to its substrate and cofactors and provide insights into the complicated regulatory mechanism of PutA in bacterial physiology and pathogenicity.
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Affiliation(s)
- Peiyi Ye
- School of Pharmaceutical Sciences (Shenzhen), Shenzhen Campus of Sun Yat-sen University, Sun Yat-sen University, Shenzhen, 518107, China
- Integrative Microbiology Research Center, College of Plant Protection, South China Agricultural University, Guangzhou, 510642, China
| | - Xia Li
- School of Pharmaceutical Sciences (Shenzhen), Shenzhen Campus of Sun Yat-sen University, Sun Yat-sen University, Shenzhen, 518107, China
| | - Binbin Cui
- School of Pharmaceutical Sciences (Shenzhen), Shenzhen Campus of Sun Yat-sen University, Sun Yat-sen University, Shenzhen, 518107, China
| | - Shihao Song
- School of Pharmaceutical Sciences (Shenzhen), Shenzhen Campus of Sun Yat-sen University, Sun Yat-sen University, Shenzhen, 518107, China
- Integrative Microbiology Research Center, College of Plant Protection, South China Agricultural University, Guangzhou, 510642, China
| | - Fangfang Shen
- Integrative Microbiology Research Center, College of Plant Protection, South China Agricultural University, Guangzhou, 510642, China
| | - Xiayu Chen
- School of Pharmaceutical Sciences (Shenzhen), Shenzhen Campus of Sun Yat-sen University, Sun Yat-sen University, Shenzhen, 518107, China
| | - Gerun Wang
- School of Pharmaceutical Sciences (Shenzhen), Shenzhen Campus of Sun Yat-sen University, Sun Yat-sen University, Shenzhen, 518107, China
| | - Xiaofan Zhou
- Integrative Microbiology Research Center, College of Plant Protection, South China Agricultural University, Guangzhou, 510642, China
| | - Yinyue Deng
- School of Pharmaceutical Sciences (Shenzhen), Shenzhen Campus of Sun Yat-sen University, Sun Yat-sen University, Shenzhen, 518107, China.
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Chen M, Zhang W, Han L, Ru X, Cao Y, Hikichi Y, Ohnishi K, Pan G, Zhang Y. A CysB regulator positively regulates cysteine synthesis, expression of type III secretion system genes, and pathogenicity in Ralstonia solanacearum. MOLECULAR PLANT PATHOLOGY 2022; 23:679-692. [PMID: 35122373 PMCID: PMC8995062 DOI: 10.1111/mpp.13189] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/02/2021] [Revised: 01/11/2022] [Accepted: 01/12/2022] [Indexed: 05/27/2023]
Abstract
A syringe-like type III secretion system (T3SS) plays essential roles in the pathogenicity of Ralstonia solanacearum, which is a causal agent of bacterial wilt disease on many plant species worldwide. Here, we characterized functional roles of a CysB regulator (RSc2427) in R. solanacearum OE1-1 that was demonstrated to be responsible for cysteine synthesis, expression of the T3SS genes, and pathogenicity of R. solanacearum. The cysB mutants were cysteine auxotrophs that failed to grow in minimal medium but grew slightly in host plants. Supplementary cysteine substantially restored the impaired growth of cysB mutants both in minimal medium and inside host plants. Genes of cysU and cysI regulons have been annotated to function for R. solanacearum cysteine synthesis; CysB positively regulated expression of these genes. Moreover, CysB positively regulated expression of the T3SS genes both in vitro and in planta through the PrhG to HrpB pathway, whilst impaired expression of the T3SS genes in cysB mutants was independent of growth deficiency under nutrient-limited conditions. CysB was also demonstrated to be required for exopolysaccharide production and swimming motility, which contribute jointly to the host colonization and infection process of R. solanacearum. Thus, CysB was identified here as a novel regulator on the T3SS expression in R. solanacearum. These results provide novel insights into understanding of various biological functions of CysB regulators and complex regulatory networks on the T3SS in R. solanacearum.
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Affiliation(s)
- Min Chen
- College of Resources and EnvironmentSouthwest UniversityChongqingChina
| | - Weiqi Zhang
- College of Resources and EnvironmentSouthwest UniversityChongqingChina
| | - Liangliang Han
- College of Resources and EnvironmentSouthwest UniversityChongqingChina
| | - Xuejuan Ru
- Chongqing Academy of Agricultural SciencesChongqingChina
| | - Yuzhu Cao
- Faculty of Agriculture and Marine ScienceKochi UniversityNankokuJapan
| | - Yasufumi Hikichi
- Faculty of Agriculture and Marine ScienceKochi UniversityNankokuJapan
| | - Kouhei Ohnishi
- Faculty of Agriculture and Marine ScienceKochi UniversityNankokuJapan
| | - Guanghui Pan
- Chongqing Academy of Agricultural SciencesChongqingChina
| | - Yong Zhang
- College of Resources and EnvironmentSouthwest UniversityChongqingChina
- Interdisciplinary Research Center for Agriculture Green Development in Yangtze River BasinSouthwest UniversityChongqingChina
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Truchon AN, Hendrich CG, Bigott AF, Dalsing BL, Allen C. NorA, HmpX, and NorB Cooperate to Reduce NO Toxicity during Denitrification and Plant Pathogenesis in Ralstonia solanacearum. Microbiol Spectr 2022; 10:e0026422. [PMID: 35377234 PMCID: PMC9045102 DOI: 10.1128/spectrum.00264-22] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2022] [Accepted: 02/22/2022] [Indexed: 12/14/2022] Open
Abstract
Ralstonia solanacearum, which causes bacterial wilt disease of many crops, requires denitrifying respiration to survive in its plant host. In the hypoxic environment of plant xylem vessels, this pathogen confronts toxic oxidative radicals like nitric oxide (NO), which is generated by both bacterial denitrification and host defenses. R. solanacearum has multiple distinct mechanisms that could mitigate this stress, including putative NO-binding protein (NorA), nitric oxide reductase (NorB), and flavohaemoglobin (HmpX). During denitrification and tomato pathogenesis and in response to exogenous NO, R. solanacearum upregulated norA, norB, and hmpX. Single mutants lacking ΔnorB, ΔnorA, or ΔhmpX increased expression of many iron and sulfur metabolism genes, suggesting that the loss of even one NO detoxification system demands metabolic compensation. Single mutants suffered only moderate fitness reductions in host plants, possibly because they upregulated their remaining protective genes. However, ΔnorA/norB, ΔnorB/hmpX, and ΔnorA/hmpX double mutants grew poorly in denitrifying culture and in planta. It is likely that the loss of norA, norB, and hmpX is lethal, since the methods used to construct the double mutants could not generate a triple mutant. Functional aconitase activity assays showed that NorA, HmpX, and especially NorB are important for maintaining iron-sulfur cluster proteins. Additionally, plant defense genes were upregulated in tomatoes infected with the NO-overproducing ΔnorB mutant, suggesting that bacterial detoxification of NO reduces the ability of the plant host to perceive the presence of the pathogen. Thus, R. solanacearum's three NO detoxification systems each contribute to and are collectively essential for overcoming metabolic nitrosative stress during denitrification, for virulence and growth in the tomato, and for evading host plant defenses. IMPORTANCE The soilborne plant pathogen Ralstonia solanacearum (Rs) causes bacterial wilt, a serious and widespread threat to global food security. Rs is metabolically adapted to low-oxygen conditions, using denitrifying respiration to survive in the host and cause disease. However, bacterial denitrification and host defenses generate nitric oxide (NO), which is toxic and also alters signaling pathways in both the pathogen and its plant hosts. Rs mitigates NO with a trio of mechanistically distinct proteins: NO-reductase (NorB), predicted iron-binding (NorA), and oxidoreductase (HmpX). This redundancy, together with analysis of mutants and in-planta dual transcriptomes, indicates that maintaining low NO levels is integral to Rs fitness in tomatoes (because NO damages iron-cluster proteins) and to evading host recognition (because bacterially produced NO can trigger plant defenses).
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Affiliation(s)
- Alicia N. Truchon
- Department of Plant Pathology, University of Wisconsin-Madison, Madison, Wisconsin, USA
- Microbiology Doctoral Training Program, University of Wisconsin-Madison, Madison, Wisconsin, USA
| | - Connor G. Hendrich
- Department of Plant Pathology, University of Wisconsin-Madison, Madison, Wisconsin, USA
- Microbiology Doctoral Training Program, University of Wisconsin-Madison, Madison, Wisconsin, USA
| | - Adam F. Bigott
- Department of Plant Pathology, University of Wisconsin-Madison, Madison, Wisconsin, USA
| | - Beth L. Dalsing
- Department of Plant Pathology, University of Wisconsin-Madison, Madison, Wisconsin, USA
- Microbiology Doctoral Training Program, University of Wisconsin-Madison, Madison, Wisconsin, USA
| | - Caitilyn Allen
- Department of Plant Pathology, University of Wisconsin-Madison, Madison, Wisconsin, USA
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MacIntyre AM, Meline V, Gorman Z, Augustine SP, Dye CJ, Hamilton CD, Iyer-Pascuzzi AS, Kolomiets MV, McCulloh KA, Allen C. Trehalose increases tomato drought tolerance, induces defenses, and increases resistance to bacterial wilt disease. PLoS One 2022; 17:e0266254. [PMID: 35476629 PMCID: PMC9045674 DOI: 10.1371/journal.pone.0266254] [Citation(s) in RCA: 17] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2022] [Accepted: 03/16/2022] [Indexed: 12/13/2022] Open
Abstract
Ralstonia solanacearum causes bacterial wilt disease, leading to severe crop losses. Xylem sap from R. solanacearum-infected tomato is enriched in the disaccharide trehalose. Water-stressed plants also accumulate trehalose, which increases drought tolerance via abscisic acid (ABA) signaling. Because R. solanacearum-infected plants suffer reduced water flow, we hypothesized that bacterial wilt physiologically mimics drought stress, which trehalose could mitigate. We found that R. solanacearum-infected plants differentially expressed drought-associated genes, including those involved in ABA and trehalose metabolism, and had more ABA in xylem sap. Consistent with this, treating tomato roots with ABA reduced both stomatal conductance and stem colonization by R. solanacearum. Treating roots with trehalose increased xylem sap ABA and reduced plant water use by lowering stomatal conductance and temporarily improving water use efficiency. Trehalose treatment also upregulated expression of salicylic acid (SA)-dependent tomato defense genes; increased xylem sap levels of SA and other antimicrobial compounds; and increased bacterial wilt resistance of SA-insensitive NahG tomato plants. Additionally, trehalose treatment increased xylem concentrations of jasmonic acid and related oxylipins. Finally, trehalose-treated plants were substantially more resistant to bacterial wilt disease. Together, these data show that exogenous trehalose reduced both water stress and bacterial wilt disease and triggered systemic disease resistance, possibly through a Damage Associated Molecular Pattern (DAMP) response pathway. This suite of responses revealed unexpected linkages between plant responses to biotic and abiotic stress and suggested that R. solanacearum-infected plants increase trehalose to improve water use efficiency and increase wilt disease resistance. The pathogen may degrade trehalose to counter these efforts. Together, these results suggest that treating tomatoes with exogenous trehalose could be a practical strategy for bacterial wilt management.
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Affiliation(s)
- April M. MacIntyre
- Department of Plant Pathology, University of Wisconsin-Madison, Madison, WI, United States of America
- Department of Bacteriology, University of Wisconsin-Madison, Madison, WI, United States of America
| | - Valerian Meline
- Department of Botany and Plant Pathology, Purdue University, West Lafayette, IN, United States of America
| | - Zachary Gorman
- Department of Plant Pathology and Microbiology, Texas A&M University, College Station, TX, United States of America
| | - Steven P. Augustine
- Department of Botany, University of Wisconsin-Madison, Madison, WI, United States of America
| | - Carolyn J. Dye
- Department of Plant Pathology, University of Wisconsin-Madison, Madison, WI, United States of America
| | - Corri D. Hamilton
- Department of Plant Pathology, University of Wisconsin-Madison, Madison, WI, United States of America
| | - Anjali S. Iyer-Pascuzzi
- Department of Botany and Plant Pathology, Purdue University, West Lafayette, IN, United States of America
| | - Michael V. Kolomiets
- Department of Plant Pathology and Microbiology, Texas A&M University, College Station, TX, United States of America
| | - Katherine A. McCulloh
- Department of Botany, University of Wisconsin-Madison, Madison, WI, United States of America
| | - Caitilyn Allen
- Department of Plant Pathology, University of Wisconsin-Madison, Madison, WI, United States of America
- * E-mail:
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Precision Probiotics in Agroecosystems: Multiple Strategies of Native Soil Microbiotas for Conquering the Competitor Ralstonia solanacearum. mSystems 2022; 7:e0115921. [PMID: 35469423 PMCID: PMC9239239 DOI: 10.1128/msystems.01159-21] [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: 11/20/2022] Open
Abstract
Ralstonia solanacearum (Rs), a soilborne phytopathogen, causes bacterial wilt disease in a broad range of hosts. Common approaches, for example, the direct reduction of the pathogen using classic single broad-spectrum probiotics, suffer from poor colonization efficiency, interference by resident microbiota, and nonnative-microorganism invasion. The soil microbiota plays an important role in plant health. Revealing the intrinsic linkage between the microbiome and the occurrence of disease and then applying it to agroecosystems for the precise control of soilborne diseases should be an effective strategy. Here, we surveyed the differences in the microbiome between healthy and diseased soils used for tomato planting across six climatic regions in China by using 16S rRNA amplicon and metagenomic sequencing. The roles of species associated with disease symptoms were further validated. Healthy soil possessed more diverse bacterial communities and more potential plant probiotics than diseased soil. Healthy soil simultaneously presented multiple strategies, including specifically antagonizing Rs, decreasing the gene expression of the type III secretion system of Rs, and competing for nutrition with Rs. Bacteria enriched in diseased samples promoted the progression of tomato bacterial wilt by strengthening the chemotaxis of pathogens. Therefore, Rs and its collaborators should be jointly combatted for disease suppression. Our research provides integrated insights into a multifaceted strategy for the biocontrol of tomato bacterial wilt based on the individual network of local microbiota. IMPORTANCE In the current work, the relationship between the soil microbiota and tomato bacterial wilt on a large scale offered us a comprehensive understanding of the disease. The delicate strategy of the microbiota in soil used for growing tomatoes to conquer the strong competitor, Rs, was revealed by microbiome research. The collaborators of Rs that coexist in a common niche with Rs strengthened our understanding of the pathogenesis of bacterial wilt. Bacteria enriched in healthy soil that antagonized pathogens with high specificity provide a novel view for ecofriendly probiotics mining. Our study offers new perspectives on soilborne-pathogen biocontrol in agroecosystems by decoding the rule of the natural ecosystem.
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Ray JD, Subandiyah S, Rincón-Flórez VA, Prakoso AB, Carvalhais LC, Drenth A. Susceptibility of the Banana Inflorescence to Blood Disease. PHYTOPATHOLOGY 2022; 112:803-810. [PMID: 34636648 DOI: 10.1094/phyto-07-21-0311-r] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
The bacterium Ralstonia syzygii subsp. celebesensis causes Blood disease of banana, a vascular wilt of economic significance in Indonesia and Malaysia. Blood disease has expanded its geographic range in the last 20 years and is an emerging threat to Southeast Asian banana production. Many aspects of the disease cycle and biology are not well understood, including the ability of different parts of the female and male inflorescence of banana to act as infection courts. This study confirms that the banana varieties of Cavendish, and Kepok 'Kuning' are susceptible to Blood disease and that an inoculum concentration of 102 CFU/ml of R. syzygii subsp. celebesensis is adequate to initiate disease after pseudostem inoculation. Data show that infection occurs through both the male and female parts of a banana inflorescence and the rachis when snapped to remove the male bell. The infection courts are the female flowers, the male bell bract scar, the male bell flower cushion, the snapped rachis, and deflowered fingers. The location of these infection courts concurs with the dye studies demonstrating that dye externally applied to these plants parts enters the plant vascular system. Thus, the hypothesis is supported that infection of R. syzygii subsp. celebesensis occurs through open xylem vessels of the male and female parts of the banana inflorescence.
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Affiliation(s)
- Jane D Ray
- Centre for Horticultural Science, The University of Queensland, Brisbane 4001, Australia
| | - Siti Subandiyah
- Research Center for Biotechnology, Universitas Gadjah Mada, Yogyakarta 55281, Indonesia
- Department of Entomology and Plant Pathology, Universitas Gadjah Mada, Yogyakarta 55281, Indonesia
| | - Vivian A Rincón-Flórez
- Centre for Horticultural Science, The University of Queensland, Brisbane 4001, Australia
| | - Ady B Prakoso
- Department of Entomology and Plant Pathology, Universitas Gadjah Mada, Yogyakarta 55281, Indonesia
| | - Lilia C Carvalhais
- Centre for Horticultural Science, The University of Queensland, Brisbane 4001, Australia
| | - André Drenth
- Centre for Horticultural Science, The University of Queensland, Brisbane 4001, Australia
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Tan X, Dai X, Chen T, Wu Y, Yang D, Zheng Y, Chen H, Wan X, Yang Y. Complete Genome Sequence Analysis of Ralstonia solanacearum Strain PeaFJ1 Provides Insights Into Its Strong Virulence in Peanut Plants. Front Microbiol 2022; 13:830900. [PMID: 35273586 PMCID: PMC8904134 DOI: 10.3389/fmicb.2022.830900] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2021] [Accepted: 01/12/2022] [Indexed: 11/22/2022] Open
Abstract
The bacterial wilt of peanut (Arachis hypogaea L.) caused by Ralstonia solanacearum is a devastating soil-borne disease that seriously restricted the world peanut production. However, the molecular mechanism of R. solanacearum–peanut interaction remains largely unknown. We found that R. solanacearum HA4-1 and PeaFJ1 isolated from peanut plants showed different pathogenicity by inoculating more than 110 cultivated peanuts. Phylogenetic tree analysis demonstrated that HA4-1 and PeaFJ1 both belonged to phylotype I and sequevar 14M, which indicates a high degree of genomic homology between them. Genomic sequencing and comparative genomic analysis of PeaFJ1 revealed 153 strain-specific genes compared with HA4-1. The PeaFJ1 strain-specific genes consisted of diverse virulence-related genes including LysR-type transcriptional regulators, two-component system-related genes, and genes contributing to motility and adhesion. In addition, the repertoire of the type III effectors of PeaFJ1 was bioinformatically compared with that of HA4-1 to find the candidate effectors responsible for their different virulences. There are 79 effectors in the PeaFJ1 genome, only 4 of which are different effectors compared with HA4-1, including RipS4, RipBB, RipBS, and RS_T3E_Hyp6. Based on the virulence profiles of the two strains against peanuts, we speculated that RipS4 and RipBB are candidate virulence effectors in PeaFJ1 while RipBS and RS_T3E_Hyp6 are avirulence effectors in HA4-1. In general, our research greatly reduced the scope of virulence-related genes and made it easier to find out the candidates that caused the difference in pathogenicity between the two strains. These results will help to reveal the molecular mechanism of peanut–R. solanacearum interaction and develop targeted control strategies in the future.
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Affiliation(s)
- Xiaodan Tan
- Guangzhou Key Laboratory for Research and Development of Crop Germplasm Resources, Zhongkai University of Agriculture and Engineering, Guangzhou, China
| | - Xiaoqiu Dai
- Guangzhou Key Laboratory for Research and Development of Crop Germplasm Resources, Zhongkai University of Agriculture and Engineering, Guangzhou, China
| | - Ting Chen
- Guangzhou Key Laboratory for Research and Development of Crop Germplasm Resources, Zhongkai University of Agriculture and Engineering, Guangzhou, China
| | - Yushuang Wu
- Guangzhou Key Laboratory for Research and Development of Crop Germplasm Resources, Zhongkai University of Agriculture and Engineering, Guangzhou, China
| | - Dong Yang
- Guangzhou Key Laboratory for Research and Development of Crop Germplasm Resources, Zhongkai University of Agriculture and Engineering, Guangzhou, China
| | - Yixiong Zheng
- Guangzhou Key Laboratory for Research and Development of Crop Germplasm Resources, Zhongkai University of Agriculture and Engineering, Guangzhou, China
| | - Huilan Chen
- Key Laboratory of Horticultural Plant Biology (HZAU), Ministry of Education, Key Laboratory of Potato Biology and Biotechnology (HZAU), Ministry of Agriculture and Rural Affairs, Huazhong Agricultural University, Wuhan, China
| | - Xiaorong Wan
- Guangzhou Key Laboratory for Research and Development of Crop Germplasm Resources, Zhongkai University of Agriculture and Engineering, Guangzhou, China
| | - Yong Yang
- Guangzhou Key Laboratory for Research and Development of Crop Germplasm Resources, Zhongkai University of Agriculture and Engineering, Guangzhou, China
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Yang S, Cai W, Shen L, Cao J, Liu C, Hu J, Guan D, He S. A CaCDPK29-CaWRKY27b module promotes CaWRKY40-mediated thermotolerance and immunity to Ralstonia solanacearum in pepper. THE NEW PHYTOLOGIST 2022; 233:1843-1863. [PMID: 34854082 DOI: 10.1111/nph.17891] [Citation(s) in RCA: 26] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/28/2021] [Accepted: 11/18/2021] [Indexed: 06/13/2023]
Abstract
CaWRKY40 in pepper (Capsicum annuum) promotes immune responses to Ralstonia solanacearum infection (RSI) and to high-temperature, high-humidity (HTHH) stress, but how it interacts with upstream signalling components remains poorly understood. Here, using approaches of reverse genetics, biochemical and molecular biology we functionally characterised the relationships among the WRKYGMK-containing WRKY protein CaWRKY27b, the calcium-dependent protein kinase CaCDPK29, and CaWRKY40 during pepper response to RSI or HTHH. Our data indicate that CaWRKY27b is upregulated and translocated from the cytoplasm to the nucleus upon phosphorylation of Ser137 in the nuclear localisation signal by CaCDPK29. Using electrophoretic mobility shift assays and microscale thermophoresis, we observed that, due to the replacement of Q by M in the conserved WRKYGQK, CaWRKY27b in the nucleus failed to bind to W-boxes in the promoters of immunity- and thermotolerance-related marker genes. Instead, CaWRKY27b interacted with CaWRKY40 and promoted its binding and positive regulation of the tested marker genes including CaNPR1, CaDEF1 and CaHSP24. Notably, mutation of the WRKYGMK motif in CaWRKY27b to WRKYGQK restored the W-box binding ability. Our data therefore suggest that CaWRKY27b is phosphorylated by CaCDPK29 and acts as a transcriptional activator of CaWRKY40 during the pepper response to RSI and HTHH.
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Affiliation(s)
- Sheng Yang
- National Education Ministry Key Laboratory of Plant Genetic Improvement and Comprehensive Utilization, Fujian Agriculture and Forestry University, Fuzhou, Fujian, 350002, China
- Key Laboratory of Applied Genetics of Universities in Fujian Province, Fujian Agriculture and Forestry University, Fuzhou, Fujian, 350002, China
- Agricultural College, Fujian Agriculture and Forestry University, Fuzhou, Fujian, 350002, China
| | - Weiwei Cai
- National Education Ministry Key Laboratory of Plant Genetic Improvement and Comprehensive Utilization, Fujian Agriculture and Forestry University, Fuzhou, Fujian, 350002, China
- Key Laboratory of Applied Genetics of Universities in Fujian Province, Fujian Agriculture and Forestry University, Fuzhou, Fujian, 350002, China
- Agricultural College, Fujian Agriculture and Forestry University, Fuzhou, Fujian, 350002, China
| | - Lei Shen
- National Education Ministry Key Laboratory of Plant Genetic Improvement and Comprehensive Utilization, Fujian Agriculture and Forestry University, Fuzhou, Fujian, 350002, China
- Key Laboratory of Applied Genetics of Universities in Fujian Province, Fujian Agriculture and Forestry University, Fuzhou, Fujian, 350002, China
- Agricultural College, Fujian Agriculture and Forestry University, Fuzhou, Fujian, 350002, China
| | - Jianshen Cao
- National Education Ministry Key Laboratory of Plant Genetic Improvement and Comprehensive Utilization, Fujian Agriculture and Forestry University, Fuzhou, Fujian, 350002, China
- Key Laboratory of Applied Genetics of Universities in Fujian Province, Fujian Agriculture and Forestry University, Fuzhou, Fujian, 350002, China
- Agricultural College, Fujian Agriculture and Forestry University, Fuzhou, Fujian, 350002, China
| | - Cailing Liu
- Institute of Soil and Fertilizer, Fujian Academy of Agricultural Sciences, Fuzhou, Fujian, 350002, China
| | - Jiong Hu
- National Education Ministry Key Laboratory of Plant Genetic Improvement and Comprehensive Utilization, Fujian Agriculture and Forestry University, Fuzhou, Fujian, 350002, China
- Key Laboratory of Applied Genetics of Universities in Fujian Province, Fujian Agriculture and Forestry University, Fuzhou, Fujian, 350002, China
- Agricultural College, Fujian Agriculture and Forestry University, Fuzhou, Fujian, 350002, China
| | - Deyi Guan
- National Education Ministry Key Laboratory of Plant Genetic Improvement and Comprehensive Utilization, Fujian Agriculture and Forestry University, Fuzhou, Fujian, 350002, China
- Key Laboratory of Applied Genetics of Universities in Fujian Province, Fujian Agriculture and Forestry University, Fuzhou, Fujian, 350002, China
- Agricultural College, Fujian Agriculture and Forestry University, Fuzhou, Fujian, 350002, China
| | - Shuilin He
- National Education Ministry Key Laboratory of Plant Genetic Improvement and Comprehensive Utilization, Fujian Agriculture and Forestry University, Fuzhou, Fujian, 350002, China
- Key Laboratory of Applied Genetics of Universities in Fujian Province, Fujian Agriculture and Forestry University, Fuzhou, Fujian, 350002, China
- Agricultural College, Fujian Agriculture and Forestry University, Fuzhou, Fujian, 350002, China
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Garduño-Félix KG, Ramirez K, Salazar-Salas NY, Amabilis-Sosa LE, Rochín-Medina JJ. Phenolic profile in black sesame sprouts biostimulated with Bacillus clausii. JOURNAL OF FOOD MEASUREMENT AND CHARACTERIZATION 2021. [DOI: 10.1007/s11694-021-01115-1] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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Takemura C, Senuma W, Hayashi K, Minami A, Terazawa Y, Kaneoka C, Sakata M, Chen M, Zhang Y, Nobori T, Sato M, Kiba A, Ohnishi K, Tsuda K, Kai K, Hikichi Y. PhcQ mainly contributes to the regulation of quorum sensing-dependent genes, in which PhcR is partially involved, in Ralstonia pseudosolanacearum strain OE1-1. MOLECULAR PLANT PATHOLOGY 2021; 22:1538-1552. [PMID: 34423519 PMCID: PMC8578825 DOI: 10.1111/mpp.13124] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/18/2021] [Revised: 08/04/2021] [Accepted: 08/04/2021] [Indexed: 05/29/2023]
Abstract
The gram-negative plant-pathogenic β-proteobacterium Ralstonia pseudosolanacearum strain OE1-1 produces methyl 3-hydroxymyristate as a quorum sensing (QS) signal via the methyltransferase PhcB and senses the chemical through the sensor histidine kinase PhcS. This leads to functionalization of the LysR family transcriptional regulator PhcA, regulating QS-dependent genes responsible for the QS-dependent phenotypes including virulence. The phc operon consists of phcB, phcS, phcR, and phcQ, with the latter two encoding regulator proteins with a receiver domain and a histidine kinase domain and with a receiver domain, respectively. To elucidate the function of PhcR and PhcQ in the regulation of QS-dependent genes, we generated phcR-deletion and phcQ-deletion mutants. Though the QS-dependent phenotypes of the phcR-deletion mutant were largely unchanged, deletion of phcQ led to a significant change in the QS-dependent phenotypes. Transcriptome analysis coupled with quantitative reverse transcription-PCR and RNA-sequencing revealed that phcB, phcK, and phcA in the phcR-deletion and phcQ-deletion mutants were expressed at similar levels as in strain OE1-1. Compared with strain OE1-1, expression of 22.9% and 26.4% of positively and negatively QS-dependent genes, respectively, was significantly altered in the phcR-deletion mutant. However, expression of 96.8% and 66.9% of positively and negatively QS-dependent genes, respectively, was significantly altered in the phcQ-deletion mutant. Furthermore, a strong positive correlation of expression of these QS-dependent genes was observed between the phcQ-deletion and phcA-deletion mutants. Our results indicate that PhcQ mainly contributes to the regulation of QS-dependent genes, in which PhcR is partially involved.
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Affiliation(s)
- Chika Takemura
- Faculty of Agriculture and Marine ScienceKochi UniversityNankokuJapan
| | - Wakana Senuma
- Faculty of Agriculture and Marine ScienceKochi UniversityNankokuJapan
- Present address:
Central Research InstituteIshihara Sangyo Kaisha, LTD.KusatsuShigaJapan
| | - Kazusa Hayashi
- Faculty of Agriculture and Marine ScienceKochi UniversityNankokuJapan
- Present address:
Agriculture Research CenterKochi PrefecturalNankokuJapan
| | - Ayaka Minami
- Faculty of Agriculture and Marine ScienceKochi UniversityNankokuJapan
| | - Yuki Terazawa
- Faculty of Agriculture and Marine ScienceKochi UniversityNankokuJapan
| | - Chisaki Kaneoka
- Graduate School of Life and Environmental SciencesOsaka Prefecture UniversitySakaiJapan
| | - Megumi Sakata
- Graduate School of Life and Environmental SciencesOsaka Prefecture UniversitySakaiJapan
| | - Min Chen
- College of Resources and EnvironmentSouthwest UniversityChongqingChina
| | - Yong Zhang
- Interdisciplinary Research Center for Agriculture Green Development in Yangtze River BasinSouthwest UniversityChongqingChina
| | - Tatsuya Nobori
- Salk Institute for Biological StudiesLa JollaCaliforniaUSA
| | - Masanao Sato
- Graduate School of AgricultureHokkaido UniversitySapporoJapan
| | - Akinori Kiba
- Faculty of Agriculture and Marine ScienceKochi UniversityNankokuJapan
| | - Kouhei Ohnishi
- Faculty of Agriculture and Marine ScienceKochi UniversityNankokuJapan
| | - Kenichi Tsuda
- State Key Laboratory of Agricultural Microbiology, Interdisciplinary Sciences Research Institute, College of Plant Science and TechnologyHuazhong Agricultural UniversityWuhanChina
| | - Kenji Kai
- Graduate School of Life and Environmental SciencesOsaka Prefecture UniversitySakaiJapan
| | - Yasufumi Hikichi
- Faculty of Agriculture and Marine ScienceKochi UniversityNankokuJapan
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Colin R, Ni B, Laganenka L, Sourjik V. Multiple functions of flagellar motility and chemotaxis in bacterial physiology. FEMS Microbiol Rev 2021; 45:fuab038. [PMID: 34227665 PMCID: PMC8632791 DOI: 10.1093/femsre/fuab038] [Citation(s) in RCA: 113] [Impact Index Per Article: 37.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2021] [Accepted: 07/02/2021] [Indexed: 12/13/2022] Open
Abstract
Most swimming bacteria are capable of following gradients of nutrients, signaling molecules and other environmental factors that affect bacterial physiology. This tactic behavior became one of the most-studied model systems for signal transduction and quantitative biology, and underlying molecular mechanisms are well characterized in Escherichia coli and several other model bacteria. In this review, we focus primarily on less understood aspect of bacterial chemotaxis, namely its physiological relevance for individual bacterial cells and for bacterial populations. As evident from multiple recent studies, even for the same bacterial species flagellar motility and chemotaxis might serve multiple roles, depending on the physiological and environmental conditions. Among these, finding sources of nutrients and more generally locating niches that are optimal for growth appear to be one of the major functions of bacterial chemotaxis, which could explain many chemoeffector preferences as well as flagellar gene regulation. Chemotaxis might also generally enhance efficiency of environmental colonization by motile bacteria, which involves intricate interplay between individual and collective behaviors and trade-offs between growth and motility. Finally, motility and chemotaxis play multiple roles in collective behaviors of bacteria including swarming, biofilm formation and autoaggregation, as well as in their interactions with animal and plant hosts.
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Affiliation(s)
- Remy Colin
- Max Planck Institute for Terrestrial Microbiology & Center for Synthetic Microbiology (SYNMIKRO), Karl-von-Frisch Strasse 16, Marburg D-35043, Germany
| | - Bin Ni
- Max Planck Institute for Terrestrial Microbiology & Center for Synthetic Microbiology (SYNMIKRO), Karl-von-Frisch Strasse 16, Marburg D-35043, Germany
- College of Resources and Environmental Science, National Academy of Agriculture Green Development, China Agricultural University, Yuanmingyuan Xilu No. 2, Beijing 100193, China
| | - Leanid Laganenka
- Institute of Microbiology, D-BIOL, ETH Zürich, Vladimir-Prelog-Weg 4, Zürich 8093, Switzerland
| | - Victor Sourjik
- Max Planck Institute for Terrestrial Microbiology & Center for Synthetic Microbiology (SYNMIKRO), Karl-von-Frisch Strasse 16, Marburg D-35043, Germany
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Peng J, Liu H, Shen M, Chen R, Li J, Dong Y. The inhibitory effects of different types of Brassica seed meals on the virulence of Ralstonia solanacearum. PEST MANAGEMENT SCIENCE 2021; 77:5129-5138. [PMID: 34251090 DOI: 10.1002/ps.6552] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/05/2021] [Accepted: 07/12/2021] [Indexed: 06/13/2023]
Abstract
BACKGROUND Understanding the specific inhibitory effects of different Brassica seed meals (BSMs) on soilborne pathogens is important for their application as biocontrol agents for controlling plant disease. In this study, the seed meals of Brassica napus L. (BnSM), Brassica campestris L. (BcSM), and Brassica juncea L. (BjSM), and the combined seed meal of BcSM and BjSM (CSM, 1:1), were selected for investigation. The inhibitory effects of these seed meals on the plant pathogen Ralstonia solanacearum (Smith) and tomato bacterial wilt, were assessed and compared. RESULTS All the BSMs significantly inhibited the growth of R. solanacearum in vitro. Furthermore, the BSMs could effectively suppress R. solanacearum virulence traits, including motility, exopolysaccharide production, dehydrogenase activity, virulence-related gene expression, and colonization in the soil. Among them, BjSM showed the best inhibiting effects, and CSM displayed synergic toxicity against R. solanacearum. In addition, the predominant antibacterial compounds in BcSM and BjSM were identified as the volatile compounds, 3-butenyl isothiocyanate and allyl isothiocyanate, respectively. Finally, pot experiment verified that the control effects of BjSM and CSM on tomato wilt reached more than 90%. CONCLUSION This is the first study to report on the ability of different kinds of BSMs to suppress the virulence of R. solanacearum and biocontrol efficiencies against bacterial wilt in tomato plants. Furtherly, the main antibacterial compounds in the BSMs were identified. The results demonstrated that CSM may possess potential for controlling bacterial wilt caused by R. solanacearum. The results provide a fresh perspective for comprehending the mechanism underlying BSM suppression of pathogens and plant disease.
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Affiliation(s)
- Junwei Peng
- CAS Key Laboratory of Soil Environment and Pollution Remediation, Institute of Soil Science, Chinese Academy of Sciences, Nanjing, China
- University of Chinese Academy of Sciences, Beijing, China
| | - Hong Liu
- CAS Key Laboratory of Soil Environment and Pollution Remediation, Institute of Soil Science, Chinese Academy of Sciences, Nanjing, China
- University of Chinese Academy of Sciences, Beijing, China
| | - Minchong Shen
- CAS Key Laboratory of Soil Environment and Pollution Remediation, Institute of Soil Science, Chinese Academy of Sciences, Nanjing, China
- University of Chinese Academy of Sciences, Beijing, China
| | - Ruihuan Chen
- University of Chinese Academy of Sciences, Beijing, China
- College of Life and Environmental Science, Wenzhou University, Wenzhou, China
| | - Jiangang Li
- CAS Key Laboratory of Soil Environment and Pollution Remediation, Institute of Soil Science, Chinese Academy of Sciences, Nanjing, China
| | - Yuanhua Dong
- CAS Key Laboratory of Soil Environment and Pollution Remediation, Institute of Soil Science, Chinese Academy of Sciences, Nanjing, China
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Zhou X, Wang Y, Li C, Xu Y, Su X, Yang T, Zhang X. Differential Expression Pattern of Pathogenicity-Related Genes of Ralstonia pseudosolanacearum YQ Responding to Tissue Debris of Casuarina equisetifolia. PHYTOPATHOLOGY 2021; 111:1918-1926. [PMID: 33822646 DOI: 10.1094/phyto-11-20-0490-r] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
Ralstonia solanacearum species complex (RSSC) contains a group of destructive plant pathogenic bacteria, causing bacterial wilt of >200 species of crops and trees, such as Casuarina equisetifolia, worldwide. RSSC can survive in the soil environment for a long time and start infection after activation by host plants. This study conducted a transcriptome analysis on the expression pattern of the pathogenicity-related genes of a new isolated RSSC strain YQ (Ralstonia pseudosolanacearum phylotype I-16) in response to C. equisetifolia cladophyll (a branch of a stem that resembles and functions as a leaf) and root debris under in vitro culture. The cladophyll debris induced more genes up-regulated than the root debris, including pathogenicity-related genes involved in motility, effectors, type III secretion systems, quorum sensing, and plant cell wall degradation. Besides, many differentially expressed genes were related to transcriptional regulator such as cyclic dimeric guanosine monophosphate. Moreover, the cultures with cladophyll debris induced a faster wilting in bioassays, and the cell swimming was enhanced by cladophyll exudate. C. equisetifolia cladophylls could activate the expression of pathogenicity-related genes of strain YQ and accelerate infection. Our findings suggest that litterfall management in C. equisetifolia forests, or even other plantations, should receive attention to prevent the induction of bacterial wilt disease caused by RSSC.
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Affiliation(s)
- Xiang Zhou
- Collaborative Innovation Center of Zhejiang Green Pesticide, National Joint Local Engineering Laboratory of Biopesticide High-Efficient Preparation, School of Forestry and Biotechnology, Zhejiang A&F University, Hangzhou 311300, People's Republic of China
| | - Yue Wang
- Collaborative Innovation Center of Zhejiang Green Pesticide, National Joint Local Engineering Laboratory of Biopesticide High-Efficient Preparation, School of Forestry and Biotechnology, Zhejiang A&F University, Hangzhou 311300, People's Republic of China
| | - Chuqiao Li
- Collaborative Innovation Center of Zhejiang Green Pesticide, National Joint Local Engineering Laboratory of Biopesticide High-Efficient Preparation, School of Forestry and Biotechnology, Zhejiang A&F University, Hangzhou 311300, People's Republic of China
| | - Yuanyou Xu
- Collaborative Innovation Center of Zhejiang Green Pesticide, National Joint Local Engineering Laboratory of Biopesticide High-Efficient Preparation, School of Forestry and Biotechnology, Zhejiang A&F University, Hangzhou 311300, People's Republic of China
| | - Xiu Su
- Collaborative Innovation Center of Zhejiang Green Pesticide, National Joint Local Engineering Laboratory of Biopesticide High-Efficient Preparation, School of Forestry and Biotechnology, Zhejiang A&F University, Hangzhou 311300, People's Republic of China
| | - Tian Yang
- Collaborative Innovation Center of Zhejiang Green Pesticide, National Joint Local Engineering Laboratory of Biopesticide High-Efficient Preparation, School of Forestry and Biotechnology, Zhejiang A&F University, Hangzhou 311300, People's Republic of China
| | - Xinqi Zhang
- Collaborative Innovation Center of Zhejiang Green Pesticide, National Joint Local Engineering Laboratory of Biopesticide High-Efficient Preparation, School of Forestry and Biotechnology, Zhejiang A&F University, Hangzhou 311300, People's Republic of China
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46
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Su Y, Xu Y, Liang H, Yuan G, Wu X, Zheng D. Genome-Wide Identification of Ralstonia solanacearum Genes Required for Survival in Tomato Plants. mSystems 2021; 6:e0083821. [PMID: 34636662 PMCID: PMC8510521 DOI: 10.1128/msystems.00838-21] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2021] [Accepted: 09/24/2021] [Indexed: 01/22/2023] Open
Abstract
Ralstonia solanacearum is an extremely destructive phytopathogenic bacterium for which there is no effective control method. Though many pathogenic factors have been identified, the survival strategies of R. solanacearum in host plants remain unclear. Transposon insertion sequencing (Tn-seq) is a high-throughput genetic screening technology. This study conducted a Tn-seq analysis using the in planta environment as selective pressure to identify R. solanacearum genes required for survival in tomato plants. One hundred thirty genes were identified as putative genes required for survival in tomato plants. Sixty-three of these genes were classified into four Clusters of Orthologous Groups categories. The absence of genes that encode the outer membrane lipoprotein LolB (RS_RS01965) or the membrane protein RS_RS04475 severely decreased the in planta fitness of R. solanacearum. RS_RS09970 and RS_RS04490 are involved in tryptophan and serine biosynthesis, respectively. Mutants that lack RS_RS09970 or RS_RS04490 did not cause any wilt symptoms in susceptible tomato plants. These results confirmed the importance of genes related to "cell wall/membrane/envelope biogenesis" and "amino acid transport and metabolism" for survival in plants. The gene encoding NADH-quinone oxidoreductase subunit B (RS_RS10340) is one of the 13 identified genes involved in "energy production and conversion," and the Clp protease gene (RS_RS08645) is one of the 11 identified genes assigned to "posttranslational modification, protein turnover, and chaperones." Both genes were confirmed to be required for survival in plants. In conclusion, this study globally identified and validated R. solanacearum genes required for survival in tomato plants and provided essential information for a more complete view of the pathogenic mechanism of R. solanacearum. IMPORTANCE Tomato plant xylem is a nutritionally limiting and dynamically changing habitat. Studies on how R. solanacearum survives in this hostile environment are important for our full understanding of the pathogenic mechanism of this bacterium. Though many omics approaches have been employed to study in planta survival strategies, the direct genome-wide identification of R. solanacearum genes required for survival in plants is still lacking. This study performed a Tn-seq analysis in R. solanacearum and revealed that genes in the categories "cell wall/membrane/envelope biogenesis," "amino acid transport and metabolism," "energy production and conversion," "posttranslational modification, protein turnover, chaperones" and others play important roles in the survival of R. solanacearum in tomato plants.
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Affiliation(s)
- Yaxing Su
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-bioresources, Guangxi Key Laboratory of Agro-Environment and Agro-Product Safety, College of Agriculture, Guangxi University, Nanning, People’s Republic of China
| | - Yanan Xu
- Pharmaceutical College, Guangxi Medical University, Nanning, People’s Republic of China
| | - Hailing Liang
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-bioresources, Guangxi Key Laboratory of Agro-Environment and Agro-Product Safety, College of Agriculture, Guangxi University, Nanning, People’s Republic of China
| | - Gaoqing Yuan
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-bioresources, Guangxi Key Laboratory of Agro-Environment and Agro-Product Safety, College of Agriculture, Guangxi University, Nanning, People’s Republic of China
| | - Xiaogang Wu
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-bioresources, Guangxi Key Laboratory of Agro-Environment and Agro-Product Safety, College of Agriculture, Guangxi University, Nanning, People’s Republic of China
| | - Dehong Zheng
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-bioresources, Guangxi Key Laboratory of Agro-Environment and Agro-Product Safety, College of Agriculture, Guangxi University, Nanning, People’s Republic of China
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Boluk G, Arizala D, Dobhal S, Zhang J, Hu J, Alvarez AM, Arif M. Genomic and Phenotypic Biology of Novel Strains of Dickeya zeae Isolated From Pineapple and Taro in Hawaii: Insights Into Genome Plasticity, Pathogenicity, and Virulence Determinants. FRONTIERS IN PLANT SCIENCE 2021; 12:663851. [PMID: 34456933 PMCID: PMC8386352 DOI: 10.3389/fpls.2021.663851] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/03/2021] [Accepted: 06/30/2021] [Indexed: 05/04/2023]
Abstract
Dickeya zeae, a bacterial plant pathogen of the family Pectobacteriaceae, is responsible for a wide range of diseases on potato, maize, rice, banana, pineapple, taro, and ornamentals and significantly reduces crop production. D. zeae causes the soft rot of taro (Colocasia esculenta) and the heart rot of pineapple (Ananas comosus). In this study, we used Pacific Biosciences single-molecule real-time (SMRT) sequencing to sequence two high-quality complete genomes of novel strains of D. zeae: PL65 (size: 4.74997 MB; depth: 701x; GC: 53.6%) and A5410 (size: 4.7792 MB; depth: 558x; GC: 53.5%) isolated from economically important Hawaiian crops, taro, and pineapple, respectively. Additional complete genomes of D. zeae representing three additional hosts (philodendron, rice, and banana) and other species used for a taxonomic comparison were retrieved from the NCBI GenBank genome database. Genomic analyses indicated the truncated type III and IV secretion systems (T3SS and T4SS) in the taro strain, which only harbored one and two genes of T3SS and T4SS, respectively, and showed high heterogeneity in the type VI secretion system (T6SS). Unlike strain EC1, which was isolated from rice and recently reclassified as D. oryzae, neither the genome PL65 nor A5410 harbors the zeamine biosynthesis gene cluster, which plays a key role in virulence of other Dickeya species. The percentages of average nucleotide identity (ANI) and digital DNA-DNA hybridization (dDDH) between the two genomes were 94.47 and 57.00, respectively. In this study, we compared the major virulence factors [plant cell wall-degrading extracellular enzymes and protease (Prt)] produced by D. zeae strains and evaluated the virulence on taro corms and pineapple leaves. Both strains produced Prts, pectate lyases (Pels), and cellulases but no significant quantitative differences were observed (p > 0.05) between the strains. All the strains produced symptoms on taro corms and pineapple leaves, but the strain PL65 produced symptoms more rapidly than others. Our study highlights the genetic constituents of pathogenicity determinants and genomic heterogeneity that will help to understand the virulence mechanisms and aggressiveness of this plant pathogen.
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Affiliation(s)
- Gamze Boluk
- Department of Plant and Environmental Protection Sciences, University of Hawai’i at Mānoa, Honolulu, HI, United States
| | - Dario Arizala
- Department of Plant and Environmental Protection Sciences, University of Hawai’i at Mānoa, Honolulu, HI, United States
| | - Shefali Dobhal
- Department of Plant and Environmental Protection Sciences, University of Hawai’i at Mānoa, Honolulu, HI, United States
| | - Jingxin Zhang
- Institute of Plant Protection, Guangdong Academy of Agricultural Sciences, Guangzhou, China
| | - John Hu
- Department of Plant and Environmental Protection Sciences, University of Hawai’i at Mānoa, Honolulu, HI, United States
| | - Anne M. Alvarez
- Department of Plant and Environmental Protection Sciences, University of Hawai’i at Mānoa, Honolulu, HI, United States
| | - Mohammad Arif
- Department of Plant and Environmental Protection Sciences, University of Hawai’i at Mānoa, Honolulu, HI, United States
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Evaluation of seed associated endophytic bacteria from tolerant chilli cv. Firingi Jolokia for their biocontrol potential against bacterial wilt disease. Microbiol Res 2021; 248:126751. [PMID: 33839507 DOI: 10.1016/j.micres.2021.126751] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2020] [Revised: 03/05/2021] [Accepted: 03/19/2021] [Indexed: 12/26/2022]
Abstract
In this study, the seed endosphere of a bacterial wilt tolerant chilli cv. Firingi Jolokia was explored in order to find effective agents for bacterial wilt disease biocontrol. A total of 32 endophytic bacteria were isolated from freshly collected seeds and six isolates were selected based on R. solanacearum inhibition assay. These isolates were identified as Bacillus subtilis (KJ-2), Bacillus velezensis (KJ-4), Leuconostoc mesenteroides (KP-1), Lactococcus lactis (LB-3), Bacillus amyloliquefaciens (WK-2), and Bacillus subtilis (WK-3) by 16S rRNA gene sequencing. In the in planta R. solanacearum inhibition assay carried out by seedling root bacterization method, Bacillus subtilis (KJ-2) exhibited highest biocontrol efficacy of 86.6 % on 7th day post R. solanacearum inoculation and a minimum biocontrol efficacy of 52.9 % was noted for Leuconostoc mesenteroides (KP-1). GC-HRMS analysis detected several known antimicrobial compounds in the extract of the culture supernatant of Bacillus subtilis (KJ-2); which may contribute to inhibition of R. solanacearum. In the growth promotion assay conducted using these isolates, only two of them namely Bacillus subtilis (KJ-2) and Bacillus amyloliquefaciens (WK-2) showed growth promotion in true leafed tomato plants. All the selected seed endophytic isolates were able to control bacterial wilt of tomato at the seedling stage and Bacillus subtilis (KJ-2) was found to be most effective in controlling the disease. The results of the present study highlighted that seed endosphere of bacterial wilt tolerant cultivar is a rich source of R. solanacearum antagonizing bacterial isolates.
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49
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Rajamma SB, Raj A, Kalampalath V, Eapen SJ. Elucidation of antibacterial effect of calcium chloride against Ralstonia pseudosolanacearum race 4 biovar 3 infecting ginger (Zingiber officinale Rosc.). Arch Microbiol 2021; 203:663-671. [PMID: 33029663 DOI: 10.1007/s00203-020-02052-1] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2020] [Revised: 08/25/2020] [Accepted: 09/15/2020] [Indexed: 11/25/2022]
Abstract
Bacterial wilt incited by Ralstonia pseudosolanacearum (Rps) race 4 biovar 3 is a serious threat to ginger (Zingiber officinale Rosc.) cultivation throughout the ginger growing tracts and warrants effective remedial measures since most of the strategies failed at field level implementation. After a series of experiments, calcium chloride was found to be effective against Rps both in vitro and in planta and its prophylactic effect has been successfully demonstrated under field conditions. CaCl2 at a concentration of > 2% significantly inhibited Rps under in vitro conditions. Calcium is an important nutritional element imparts a major role in plant disease resistance, and numerous studies have demonstrated the mitigating effect of calcium for disease management. CaCl2 being inhibitory to Rps, the mechanism of inhibition by CaCl2 against Rps was elucidated by a series of in vitro assays including swarming motility and biofilm formation. Direct inhibition was also studied using Scanning Electron Microscopy (SEM). The minimum bactericidal concentration and minimum inhibitory concentration were found to be around 3% while the EC 90 value was found to be 2.25%. The SEM analysis revealed the destruction of cell structure by making perforations on the cell surface. CaCl2 at the targeted concentrations inhibited biofilm formation as well as swarming motility of Rps. These findings suggest that CaCl2 exhibits strong antibacterial activity against Rps and has the potential to be used as an effective bactericide for Rps in managing bacterial wilt in ginger.
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Affiliation(s)
- Suseela Bhai Rajamma
- ICAR-Indian Institute of Spices Research, Marikunnu P O, Kozhikode, Kerala, 673012, India.
| | - Ammu Raj
- ICAR-Indian Institute of Spices Research, Marikunnu P O, Kozhikode, Kerala, 673012, India
| | - Vincy Kalampalath
- ICAR-Indian Institute of Spices Research, Marikunnu P O, Kozhikode, Kerala, 673012, India
| | - Santhosh J Eapen
- ICAR-Indian Institute of Spices Research, Marikunnu P O, Kozhikode, Kerala, 673012, India
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50
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Hu Y, Li Y, Yang X, Li C, Wang L, Feng J, Chen S, Li X, Yang Y. Effects of integrated biocontrol on bacterial wilt and rhizosphere bacterial community of tobacco. Sci Rep 2021; 11:2653. [PMID: 33514837 PMCID: PMC7846572 DOI: 10.1038/s41598-021-82060-3] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2020] [Accepted: 01/12/2021] [Indexed: 11/08/2022] Open
Abstract
Bacterial wilt as a soil-borne disease was caused by Ralstonia solanacearum, and seriously damages the growth of tobacco. Integrated biocontrol method was explored to control bacterial wilt. Nevertheless, the long-term effects of the integrated biocontrol method on soil bacterial community, soil physicochemical properties and the incidence of bacterial wilt are not well understood. In this study, B. amyoliquefaciens ZM9, calcium cyanamide and rice bran were applied to tobacco fields in different ways. The disease index and incidence of tobacco bacterial wilt (TBW), soil physicochemical properties, colonization ability of B. amyoliquefaciens ZM9, and rhizopshere bacterial community were investigated. The results showed that the integrated application of B. amyoliquefaciens ZM9, rice bran and calcium cyanamide had the highest control efficiency of TBW and bacteria community diversity. Additionally, the integrated biocontrol method could improve the colonization ability of B. amyoliquefaciens ZM9. Furthermore, the integrated biocontrol method could effectively suppress TBW by regulating soil physicochemical properties, promoting beneficial bacteria and antagonistic bacteria of rhizopshere soil. This strategy has prospect of overcoming the defects in application of a single antagonistic bacteria and provides new insights to understand how to improve the colonization capacity of antagonistic bacteria and control efficacy for TBW.
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Affiliation(s)
- Yun Hu
- State Key Laboratory of Biocatalysis and Enzyme Engineering, School of Life Science, Hubei University, Wuhan, 430062, China
| | - Yanyan Li
- Tobacco Research Institute of Hubei Province, Wuhan, 430030, China
| | - Xiaoqiong Yang
- State Key Laboratory of Biocatalysis and Enzyme Engineering, School of Life Science, Hubei University, Wuhan, 430062, China
| | - Chunli Li
- State Key Laboratory of Biocatalysis and Enzyme Engineering, School of Life Science, Hubei University, Wuhan, 430062, China
| | - Lin Wang
- Hubei Tobacco Industry Co., Ltd., Wuhan, 430040, China
| | - Ji Feng
- Tobacco Research Institute of Hubei Province, Wuhan, 430030, China
| | - Shouwen Chen
- State Key Laboratory of Biocatalysis and Enzyme Engineering, School of Life Science, Hubei University, Wuhan, 430062, China
| | - Xihong Li
- Tobacco Research Institute of Hubei Province, Wuhan, 430030, China.
| | - Yong Yang
- State Key Laboratory of Biocatalysis and Enzyme Engineering, School of Life Science, Hubei University, Wuhan, 430062, China.
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