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Rao W, Yue Q, Gao S, Lei M, Lin T, Pan X, Hu J, Fan G. Visible-light-driven water-soluble zinc oxide quantum dots for efficient control of citrus canker. Pest Manag Sci 2024; 80:3022-3034. [PMID: 38318944 DOI: 10.1002/ps.8010] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/24/2023] [Revised: 01/24/2024] [Accepted: 02/06/2024] [Indexed: 02/07/2024]
Abstract
BACKGROUND Citrus canker caused by Xanthomonas citri subsp. citri (Xcc) is a devastating bacterial disease that reduces citrus yield and quality, posing a serious threat to the citrus industry. Several conventional chemicals have been used to control citrus canker. However, this approach often leads to the excessive use of chemical agents, can exacerbate environmental pollution and promotes the development of resistant Xcc. Therefore, there is significant interest in the development of efficient and environmentally friendly technologies to control citrus canker. RESULTS In this study, water-soluble ZnO quantum dots (ZnO QDs) were synthesised as an efficient nanopesticide against Xcc. The results showed that the antibacterial activity of ZnO QDs irradiated with visible light [half-maximal effective concentration (EC50) = 33.18 μg mL-1] was ~3.5 times higher than that of the dark-treated group (EC50 = 114.80 μg mL-1). ZnO QDs induced the generation of reactive oxygen species (•OH, •O- 2 and 1O2) under light irradiation, resulting in DNA damage, cytoplasmic destruction, and decreased catalase and superoxide dismutase activities. Transcription analysis showed downregulation of Xcc genes related to 'biofilms, virulence, adhesion' and 'DNA transfer' exposure to ZnO QDs. More importantly, ZnO QDs also promoted the growth of citrus. CONCLUSION This research provides new insights into the photocatalytic antibacterial mechanisms of ZnO QDs and supports the development of more efficient and safer ZnO QDs-based nanopesticides to control citrus canker. © 2024 Society of Chemical Industry.
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Affiliation(s)
- Wenhua Rao
- Fujian Engineering Research Center for Green Pest Management, Fujian Key Laboratory for Monitoring and Integrated Management of Crop Pests, Institute of Plant Protection, Fujian Academy of Agricultural Sciences, Fuzhou, China
- Fuzhou Scientific Observing and Experimental Station of Crop Pests of Ministry of Agriculture and Rural Affairs, Institute of Plant Protection, Fujian Academy of Agricultural Sciences, Fujian, China
| | - Qi Yue
- Fujian Engineering Research Center for Green Pest Management, Fujian Key Laboratory for Monitoring and Integrated Management of Crop Pests, Institute of Plant Protection, Fujian Academy of Agricultural Sciences, Fuzhou, China
- College of Plant Protection, Fujian Agriculture and Forestry University, Fuzhou, People's Republic of China
| | - Shang Gao
- Fujian Engineering Research Center for Green Pest Management, Fujian Key Laboratory for Monitoring and Integrated Management of Crop Pests, Institute of Plant Protection, Fujian Academy of Agricultural Sciences, Fuzhou, China
- College of Plant Protection, Fujian Agriculture and Forestry University, Fuzhou, People's Republic of China
| | - Meiling Lei
- Fujian Engineering Research Center for Green Pest Management, Fujian Key Laboratory for Monitoring and Integrated Management of Crop Pests, Institute of Plant Protection, Fujian Academy of Agricultural Sciences, Fuzhou, China
- College of Plant Protection, Fujian Agriculture and Forestry University, Fuzhou, People's Republic of China
| | - Tao Lin
- Fujian Engineering Research Center for Green Pest Management, Fujian Key Laboratory for Monitoring and Integrated Management of Crop Pests, Institute of Plant Protection, Fujian Academy of Agricultural Sciences, Fuzhou, China
- Fuzhou Scientific Observing and Experimental Station of Crop Pests of Ministry of Agriculture and Rural Affairs, Institute of Plant Protection, Fujian Academy of Agricultural Sciences, Fujian, China
| | - Xiaohong Pan
- College of Plant Protection, Fujian Agriculture and Forestry University, Fuzhou, People's Republic of China
| | - Jinfeng Hu
- Fujian Engineering Research Center for Green Pest Management, Fujian Key Laboratory for Monitoring and Integrated Management of Crop Pests, Institute of Plant Protection, Fujian Academy of Agricultural Sciences, Fuzhou, China
- Fuzhou Scientific Observing and Experimental Station of Crop Pests of Ministry of Agriculture and Rural Affairs, Institute of Plant Protection, Fujian Academy of Agricultural Sciences, Fujian, China
| | - Guocheng Fan
- Fujian Engineering Research Center for Green Pest Management, Fujian Key Laboratory for Monitoring and Integrated Management of Crop Pests, Institute of Plant Protection, Fujian Academy of Agricultural Sciences, Fuzhou, China
- Fuzhou Scientific Observing and Experimental Station of Crop Pests of Ministry of Agriculture and Rural Affairs, Institute of Plant Protection, Fujian Academy of Agricultural Sciences, Fujian, China
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Zhang YQ, Wang X, Shi H, Siddique F, Xian J, Song A, Wang B, Wu Z, Cui ZN. Design and Synthesis of Mandelic Acid Derivatives for Suppression of Virulence via T3SS against Citrus Canker. J Agric Food Chem 2024; 72:9611-9620. [PMID: 38646906 DOI: 10.1021/acs.jafc.3c07681] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/23/2024]
Abstract
Citrus canker, a highly contagious bacterial disease caused by Xanthomonas citri subsp. citri (Xcc), poses a substantial threat to citrus crops, leading to serious reductions in fruit yield and economic losses. Most commonly used bactericides against Xcc lead to the rapid development of resistant subpopulations. Therefore, it is imperative to create novel drugs, such as type III secretion system (T3SS) inhibitors, that specifically target bacterial virulence factors rather than bacterial viability. In our study, we designed and synthesized a series of mandelic acid derivatives including 2-mercapto-1,3,4-thiazole. Seven substances were found to reduce the level of transcription of hpa1 without affecting bacterial viability. In vivo bioassays indicated that compound F9 significantly inhibited hypersensitive response and pathogenicity. RT-qPCR assays showed that compound F9 visibly suppressed the expression of Xcc T3SS-related genes as well as citrus canker susceptibility gene CsLOB1. Furthermore, the combination with compound F9 and quorum-quenching bacteria HN-8 can also obviously alleviate canker symptoms.
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Affiliation(s)
- Yu-Qing Zhang
- National Key Laboratory of Green Pesticide, Integrative Microbiology Research Center, Guangdong Province Key Laboratory of Microbial Signals and Disease Control, College of Plant Protection, South China Agricultural University, Guangzhou 510642, China
| | - Xin Wang
- National Key Laboratory of Green Pesticide, Integrative Microbiology Research Center, Guangdong Province Key Laboratory of Microbial Signals and Disease Control, College of Plant Protection, South China Agricultural University, Guangzhou 510642, China
| | - Huabin Shi
- 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
| | - Faisal Siddique
- National Key Laboratory of Green Pesticide, Integrative Microbiology Research Center, Guangdong Province Key Laboratory of Microbial Signals and Disease Control, College of Plant Protection, South China Agricultural University, Guangzhou 510642, China
| | - Jiaxin Xian
- National Key Laboratory of Green Pesticide, Integrative Microbiology Research Center, Guangdong Province Key Laboratory of Microbial Signals and Disease Control, College of Plant Protection, South China Agricultural University, Guangzhou 510642, China
| | - Aiting Song
- Guangdong ZhenGe Biotechnology Co., Ltd., Zhaoqing 526040, China
| | - Boli Wang
- Guangdong ZhenGe Biotechnology Co., Ltd., Zhaoqing 526040, China
| | - Zhibing Wu
- 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
| | - Zi-Ning Cui
- National Key Laboratory of Green Pesticide, Integrative Microbiology Research Center, Guangdong Province Key Laboratory of Microbial Signals and Disease Control, College of Plant Protection, South China Agricultural University, Guangzhou 510642, China
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Pena MM, Martins TZ, Teper D, Zamuner C, Alves HA, Ferreira H, Wang N, Ferro MIT, Ferro JA. EnvC Homolog Encoded by Xanthomonas citri subsp. citri Is Necessary for Cell Division and Virulence. Microorganisms 2024; 12:691. [PMID: 38674634 PMCID: PMC11051873 DOI: 10.3390/microorganisms12040691] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2023] [Revised: 03/16/2024] [Accepted: 03/21/2024] [Indexed: 04/28/2024] Open
Abstract
Peptidoglycan hydrolases are enzymes responsible for breaking the peptidoglycan present in the bacterial cell wall, facilitating cell growth, cell division and peptidoglycan turnover. Xanthomonas citri subsp. citri (X. citri), the causal agent of citrus canker, encodes an Escherichia coli M23 peptidase EnvC homolog. EnvC is a LytM factor essential for cleaving the septal peptidoglycan, thereby facilitating the separation of daughter cells. In this study, the investigation focused on EnvC contribution to the virulence and cell separation of X. citri. It was observed that disruption of the X. citri envC gene (ΔenvC) led to a reduction in virulence. Upon inoculation into leaves of Rangpur lime (Citrus limonia Osbeck), the X. citri ΔenvC exhibited a delayed onset of citrus canker symptoms compared with the wild-type X. citri. Mutant complementation restored the wild-type phenotype. Sub-cellular localization confirmed that X. citri EnvC is a periplasmic protein. Moreover, the X. citri ΔenvC mutant exhibited elongated cells, indicating a defect in cell division. These findings support the role of EnvC in the regulation of cell wall organization, cell division, and they clarify the role of this peptidase in X. citri virulence.
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Affiliation(s)
- Michelle M. Pena
- Agricultural and Livestock Microbiology Graduation Program, School of Agricultural and Veterinarian Sciences, São Paulo State University (UNESP), Jaboticabal 14884-900, SP, Brazil; (M.M.P.); (T.Z.M.)
| | - Thaisa Z. Martins
- Agricultural and Livestock Microbiology Graduation Program, School of Agricultural and Veterinarian Sciences, São Paulo State University (UNESP), Jaboticabal 14884-900, SP, Brazil; (M.M.P.); (T.Z.M.)
| | - Doron Teper
- Department of Plant Pathology and Weed Research, Institute of Plant Protection Agricultural Research Organization (ARO), Volcani Institute, Rishon LeZion 7505101, Israel;
| | - Caio Zamuner
- Biochemistry Building, Institute of Biosciences, São Paulo State University (UNESP), Rio Claro 13506-900, SP, Brazil; (C.Z.); (H.F.)
| | - Helen A. Alves
- Department of Agricultural, Livestock and Environmental Biotechnology, School of Agricultural and Veterinary Sciences, São Paulo State University (UNESP), Jaboticabal 14884-900, SP, Brazil; (H.A.A.); (M.I.T.F.)
| | - Henrique Ferreira
- Biochemistry Building, Institute of Biosciences, São Paulo State University (UNESP), Rio Claro 13506-900, SP, Brazil; (C.Z.); (H.F.)
| | - Nian Wang
- Citrus Research and Education Center, Department of Microbiology and Cell Science, Institute of Food and Agricultural Sciences, University of Florida, Lake Alfred, FL 33850, USA;
| | - Maria Inês T. Ferro
- Department of Agricultural, Livestock and Environmental Biotechnology, School of Agricultural and Veterinary Sciences, São Paulo State University (UNESP), Jaboticabal 14884-900, SP, Brazil; (H.A.A.); (M.I.T.F.)
| | - Jesus A. Ferro
- Department of Agricultural, Livestock and Environmental Biotechnology, School of Agricultural and Veterinary Sciences, São Paulo State University (UNESP), Jaboticabal 14884-900, SP, Brazil; (H.A.A.); (M.I.T.F.)
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Jia H, Omar AA, Xu J, Dalmendray J, Wang Y, Feng Y, Wang W, Hu Z, Grosser JW, Wang N. Generation of transgene-free canker-resistant Citrus sinensis cv. Hamlin in the T0 generation through Cas12a/CBE co-editing. Front Plant Sci 2024; 15:1385768. [PMID: 38595767 PMCID: PMC11002166 DOI: 10.3389/fpls.2024.1385768] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 02/13/2024] [Accepted: 03/15/2024] [Indexed: 04/11/2024]
Abstract
Citrus canker disease affects citrus production. This disease is caused by Xanthomonas citri subsp. citri (Xcc). Previous studies confirmed that during Xcc infection, PthA4, a transcriptional activator like effector (TALE), is translocated from the pathogen to host plant cells. PthA4 binds to the effector binding elements (EBEs) in the promoter region of canker susceptibility gene LOB1 (EBEPthA4-LOBP) to activate its expression and subsequently cause canker symptoms. Previously, the Cas12a/CBE co-editing method was employed to disrupt EBEPthA4-LOBP of pummelo, which is highly homozygous. However, most commercial citrus cultivars are heterozygous hybrids and more difficult to generate homozygous/biallelic mutants. Here, we employed Cas12a/CBE co-editing method to edit EBEPthA4-LOBP of Hamlin (Citrus sinensis), a commercial heterozygous hybrid citrus cultivar grown worldwide. Binary vector GFP-p1380N-ttLbCas12a:LOBP1-mPBE:ALS2:ALS1 was constructed and shown to be functional via Xcc-facilitated agroinfiltration in Hamlin leaves. This construct allows the selection of transgene-free regenerants via GFP, edits ALS to generate chlorsulfuron-resistant regenerants as a selection marker for genome editing resulting from transient expression of the T-DNA via nCas9-mPBE:ALS2:ALS1, and edits gene(s) of interest (i.e., EBEPthA4-LOBP in this study) through ttLbCas12a, thus creating transgene-free citrus. Totally, 77 plantlets were produced. Among them, 8 plantlets were transgenic plants (#HamGFP1 - #HamGFP8), 4 plantlets were transgene-free (#HamNoGFP1 - #HamNoGFP4), and the rest were wild type. Among 4 transgene-free plantlets, three lines (#HamNoGFP1, #HamNoGFP2 and #HamNoGFP3) contained biallelic mutations in EBEpthA4, and one line (#HamNoGFP4) had homozygous mutations in EBEpthA4. We achieved 5.2% transgene-free homozygous/biallelic mutation efficiency for EBEPthA4-LOBP in C. sinensis cv. Hamlin, compared to 1.9% mutation efficiency for pummelo in a previous study. Importantly, the four transgene-free plantlets and 3 transgenic plantlets that survived were resistant against citrus canker. Taken together, Cas12a/CBE co-editing method has been successfully used to generate transgene-free canker-resistant C. sinensis cv. Hamlin in the T0 generation via biallelic/homozygous editing of EBEpthA4 of the canker susceptibility gene LOB1.
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Affiliation(s)
- Hongge Jia
- Citrus Research and Education Center, Department of Microbiology and Cell Science, Institute of Food and Agricultural Sciences (IFAS), University of Florida, Lake Alfred, FL, United States
| | - Ahmad A. Omar
- Citrus Research and Education Center, Horticultural Sciences Department, Institute of Food and Agricultural Sciences (IFAS), University of Florida, Lake Alfred, FL, United States
- Biochemistry Department, Faculty of Agriculture, Zagazig University, Zagazig, Egypt
| | - Jin Xu
- Citrus Research and Education Center, Department of Microbiology and Cell Science, Institute of Food and Agricultural Sciences (IFAS), University of Florida, Lake Alfred, FL, United States
| | - Javier Dalmendray
- Citrus Research and Education Center, Department of Microbiology and Cell Science, Institute of Food and Agricultural Sciences (IFAS), University of Florida, Lake Alfred, FL, United States
| | - Yuanchun Wang
- Citrus Research and Education Center, Department of Microbiology and Cell Science, Institute of Food and Agricultural Sciences (IFAS), University of Florida, Lake Alfred, FL, United States
| | - Yu Feng
- Citrus Research and Education Center, Department of Microbiology and Cell Science, Institute of Food and Agricultural Sciences (IFAS), University of Florida, Lake Alfred, FL, United States
| | - Wenting Wang
- Citrus Research and Education Center, Department of Microbiology and Cell Science, Institute of Food and Agricultural Sciences (IFAS), University of Florida, Lake Alfred, FL, United States
| | - Zhuyuan Hu
- Citrus Research and Education Center, Department of Microbiology and Cell Science, Institute of Food and Agricultural Sciences (IFAS), University of Florida, Lake Alfred, FL, United States
| | - Jude W. Grosser
- Citrus Research and Education Center, Horticultural Sciences Department, Institute of Food and Agricultural Sciences (IFAS), University of Florida, Lake Alfred, FL, United States
| | - Nian Wang
- Citrus Research and Education Center, Department of Microbiology and Cell Science, Institute of Food and Agricultural Sciences (IFAS), University of Florida, Lake Alfred, FL, United States
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Gao L, Kumaravel K, Xiong Q, Liang Y, Ju Z, Jiang Y, Zhang J. Actinomycins produced by endophyte Streptomyces sp. GLL-9 from navel orange plant exhibit high antimicrobial effect against Xanthomonas citri susp. citri and Penicillium italicum. Pest Manag Sci 2023; 79:4679-4693. [PMID: 37450767 DOI: 10.1002/ps.7668] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/22/2023] [Revised: 06/21/2023] [Accepted: 07/15/2023] [Indexed: 07/18/2023]
Abstract
BACKGROUND Citrus canker and citrus blue mold are two severe diseases in citrus plants, which are mainly caused by Xanthomonas citri susp. citri (Xcc) and Penicillium italicum, respectively. The currently widely used pesticides for these two diseases are harmful to human health and the environment. Therefore, searching for novel antimicrobial agents, especially from natural resources, is getting increasing interest. RESULTS In this study, the crude extract of Streptomyces sp. GLL-9, an endophyte from a navel orange tree, was found to exhibit excellent antimicrobial effects against Xcc and P. italicum. Bioassay-guided isolation led to the discovery of three actinomycins (Acts), actinomycin X2 (Act-X2 ), actinomycin D (ActD), and actinomycin XOβ (Act-XOβ ). The MIC (minimum inhibitory concentration) values of Act-X2 , ActD, and Act-XOβ were 31.25, 62.50, and 62.50 μg mL-1 against Xcc, respectively, while 62.50 (Act-X2 ) and 125.00 μg mL-1 (ActD) against P. italicum, being better or comparable to the positive controls. The highest yield of Acts was obtained by solid-state fermentation with rice containing 1% L-tryptophan as a culture medium, being 6.03, 3.07, and 1.02 mg g-1 , for Act-X2 , ActD, and Act-XOβ , respectively. The ethyl acetate extract of Streptomyces sp. GLL-9 cultivated under the optimal fermentation conditions (EAE-1) can efficiently control these two citrus diseases by excessively producing reactive oxygen species (ROS) in both pathogens, damaging the cell membranes of P. italicum, and inhibiting the growth of Xcc. In addition, Act-X2 , ActD, and EAE-1 displayed broad-spectrum antifungal activity. CONCLUSION EAE-1 and Acts produced by Streptomyces sp. GLL-9 have high potential as novel antimicrobial agents against plant pathogens. © 2023 Society of Chemical Industry.
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Affiliation(s)
- Liangliang Gao
- National Engineering Research Center of Navel Orange, Gannan Normal University, Ganzhou, China
| | - Kaliaperumal Kumaravel
- Department of Orthodontics, Saveetha Dental College, Saveetha University, Chennai, India
| | - Qin Xiong
- National Engineering Research Center of Navel Orange, Gannan Normal University, Ganzhou, China
| | - Yan Liang
- National Engineering Research Center of Navel Orange, Gannan Normal University, Ganzhou, China
| | - Zhiran Ju
- Institute of Pharmaceutical Science and Technology, Zhejiang University of Technology, Hangzhou, China
| | - Yueming Jiang
- National Engineering Research Center of Navel Orange, Gannan Normal University, Ganzhou, China
- South China Botanical Garden, Chinese Academy of Science, Guangzhou, China
| | - Jun Zhang
- National Engineering Research Center of Navel Orange, Gannan Normal University, Ganzhou, China
- South China Botanical Garden, Chinese Academy of Science, Guangzhou, China
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Zhang G, Li C, Li Y, Chen D, Li Z, Wang Z, Ouyang G. Design, Synthesis, and Mechanism of Novel 9-Aliphatic Amine Tryptanthrin Derivatives against Phytopathogenic Bacteria. J Agric Food Chem 2023; 71:14232-14242. [PMID: 37749804 DOI: 10.1021/acs.jafc.3c03738] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 09/27/2023]
Abstract
Taking inspiration from the use of natural product-derived bactericide candidates in drug discovery, a series of novel 9-aliphatic amine tryptanthrin derivatives were designed, synthesized, and evaluated for their biological activity against three plant bacteria. The majority of these compounds exhibited excellent antibacterial activity in vitro. Compound 7c exhibited a significantly superior bacteriostatic effect against Xanthomonas axonopodis pv Citri (Xac), Xanthomonas oryzae pv Oryzae (Xoo), and Pseudomonas syringae pv Actinidiae (Psa) with final corrected EC50 values of 0.769, 1.29, and 15.5 μg/mL, respectively, compared to the commercial pesticide thiodiazole copper which had EC50 values of 58.8, 70.9, and 91.9 μg/mL. Preliminary mechanism studies have demonstrated that 7c is capable of altering bacterial morphology, inducing reactive oxygen species accumulation, promoting bacterial cell apoptosis, inhibiting normal cell growth, and affecting cell membrane permeability. Moreover, in vivo experiments have substantiated the effectiveness of 7c as a therapeutic and defensive agent against the citrus canker. The proteomic analysis has unveiled that the major disparities are located within the bacterial secretion system pathway, which hinders membrane transportation. These discoveries imply that 7c could be an auspicious prototype for developing antiphytopathogenic bacterial agents.
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Affiliation(s)
- Guanglong Zhang
- 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
| | - Chengpeng Li
- School of Pharmaceutical Sciences, Guizhou University, Guiyang, Guizhou 550025, China
| | - Yan Li
- School of Pharmaceutical Sciences, Guizhou University, Guiyang, Guizhou 550025, China
| | - Danping Chen
- School of Pharmaceutical Sciences, Guizhou University, Guiyang, Guizhou 550025, China
| | - Zhuirui Li
- School of Pharmaceutical Sciences, Guizhou University, Guiyang, Guizhou 550025, China
| | - Zhenchao Wang
- 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
- School of Pharmaceutical Sciences, Guizhou University, Guiyang, Guizhou 550025, China
- Guizhou Engineering Laboratory for Synthetic Drugs, Guizhou University, Guiyang, Guizhou 550025, China
| | - Guiping Ouyang
- 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
- School of Pharmaceutical Sciences, Guizhou University, Guiyang, Guizhou 550025, China
- Guizhou Engineering Laboratory for Synthetic Drugs, Guizhou University, Guiyang, Guizhou 550025, China
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Xu J, Dai S, Wang X, Gentile A, Zhang Z, Xie Q, Su Y, Li D, Wang B. Actin-Depolymerizing Factor Gene Family Analysis Revealed That CsADF4 Increased the Sensitivity of Sweet Orange to Bacterial Pathogens. Plants (Basel) 2023; 12:3054. [PMID: 37687300 PMCID: PMC10490069 DOI: 10.3390/plants12173054] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/14/2023] [Revised: 08/14/2023] [Accepted: 08/22/2023] [Indexed: 09/10/2023]
Abstract
The actin-depolymerizing factor (ADF) gene family regulates changes in actin. However, the entire ADF family in the sweet orange Citrus sinensis has not been systematically identified, and their expressions in different organs and biotic stress have not been determined. In this study, through phylogenetic analysis of the sweet orange ADF gene family, seven CsADFs were found to be highly conserved and sparsely distributed across the four chromosomes. Analysis of the cis-regulatory elements in the promoter region showed that the CsADF gene had the potential to impact the development of sweet oranges under biotic or abiotic stress. Quantitative fluorescence analysis was then performed. Seven CsADFs were differentially expressed against the invasion of Xcc and CLas pathogens. It is worth noting that the expression of CsADF4 was significantly up-regulated at 4 days post-infection. Subcellular localization results showed that CsADF4 was localized in both the nucleus and the cytoplasm. Overexpression of CsADF4 enhanced the sensitivity of sweet orange leaves to Xcc. These results suggest that CsADFs may regulate the interaction of C. sinensis and bacterial pathogens, providing a way to further explore the function and mechanisms of ADF in the sweet orange.
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Affiliation(s)
- Jing Xu
- College of Plant Protection, Hunan Agricultural University, Changsha 410128, China (X.W.)
- National Citrus Improvement Center, Hunan Agricultural University, Changsha 410128, China
| | - Suming Dai
- National Citrus Improvement Center, Hunan Agricultural University, Changsha 410128, China
- College of Horticulture, Hunan Agricultural University, Changsha 410128, China
| | - Xue Wang
- College of Plant Protection, Hunan Agricultural University, Changsha 410128, China (X.W.)
- National Citrus Improvement Center, Hunan Agricultural University, Changsha 410128, China
| | - Alessandra Gentile
- National Citrus Improvement Center, Hunan Agricultural University, Changsha 410128, China
- Department of Agriculture and Food Science, University of Catania, 95123 Catania, Italy
| | - Zhuo Zhang
- Hunan Plant Protection Institute, Hunan Academy of Agricultural Science, Changsha 410128, China
| | - Qingxiang Xie
- College of Plant Protection, Hunan Agricultural University, Changsha 410128, China (X.W.)
| | - Yajun Su
- National Citrus Improvement Center, Hunan Agricultural University, Changsha 410128, China
- College of Horticulture, Hunan Agricultural University, Changsha 410128, China
| | - Dazhi Li
- National Citrus Improvement Center, Hunan Agricultural University, Changsha 410128, China
- College of Horticulture, Hunan Agricultural University, Changsha 410128, China
| | - Bing Wang
- College of Plant Protection, Hunan Agricultural University, Changsha 410128, China (X.W.)
- National Citrus Improvement Center, Hunan Agricultural University, Changsha 410128, China
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da Silva IRR, Fernandes CC, Gonçalves DS, Martins CHG, Miranda MLD. Chemical composition and anti- Xanthomonas citri activities of essential oils from Schinus molle L. fresh and dry leaves and of its major constituent spathulenol. Nat Prod Res 2023:1-5. [PMID: 37606013 DOI: 10.1080/14786419.2023.2249584] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/23/2023]
Abstract
Citrus canker, which is caused by Xanthomonas citri, is a severe disease that affects citrus plants worldwide. This paper aimed to compare, for the first time, the chemical composition and anti-Xanthomonas citri activities of essential oils from Schinus molle fresh and dry leaves (EO-FL and EO-DL, respectively). Anti-X. citri activity of spathulenol, the major constituent of oils, was also evaluated. Activities were screened by the broth microdilution method on 96-well culture plates. Three major constituents were identified in EO-FL and EO-DL by GC-MS and GC-FID: spathulenol, β-caryophyllene and caryophyllene oxide. EO-DL (MIC = 31.25 µg/mL), EO-FL (MIC = 62.5 µg/mL) and spathulenol (MIC = 100 µg/mL) were active against X. citri strains (resistant, tolerant and sensitive to copper). Even though results showed that in vitro potential of EO-FL, EO-DL and spathulenol against X. citri, further in vivo studies are needed to prove their applicability to the biocontrol of citrus canker.
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Affiliation(s)
- Isac R R da Silva
- Instituto Federal de Educação, Ciência e Tecnologia Goiano, Campus Rio Verde, Goiás, Brazil
| | - Cassia C Fernandes
- Instituto Federal de Educação, Ciência e Tecnologia Goiano, Campus Rio Verde, Goiás, Brazil
| | - Daniela S Gonçalves
- Universidade Federal de Uberlândia, Laboratório de Ensaios Antimicrobiano (LEA), Uberlândia, Minas Gerais, Brazil
| | - Carlos H G Martins
- Universidade Federal de Uberlândia, Laboratório de Ensaios Antimicrobiano (LEA), Uberlândia, Minas Gerais, Brazil
| | - Mayker L D Miranda
- Instituto Federal de Educação, Ciência e Tecnologia do Triângulo Mineiro Campus Uberlândia Centro, Uberlândia, Minas Gerais, Brazil
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Su Y, Dai S, Li N, Gentile A, He C, Xu J, Duan K, Wang X, Wang B, Li D. Unleashing the Potential of EIL Transcription Factors in Enhancing Sweet Orange Resistance to Bacterial Pathologies: Genome-Wide Identification and Expression Profiling. Int J Mol Sci 2023; 24:12644. [PMID: 37628825 PMCID: PMC10454048 DOI: 10.3390/ijms241612644] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2023] [Revised: 08/02/2023] [Accepted: 08/05/2023] [Indexed: 08/27/2023] Open
Abstract
The ETHYLENE INSENSITIVE3-LIKE (EIL) family is one of the most important transcription factor (TF) families in plants and is involved in diverse plant physiological and biochemical processes. In this study, ten EIL transcription factors (CsEILs) in sweet orange were systematically characterized via whole-genome analysis. The CsEIL genes were unevenly distributed across the four sweet orange chromosomes. Putative cis-acting regulatory elements (CREs) associated with CsEIL were found to be involved in plant development, as well as responses to biotic and abiotic stress. Notably, quantitative reverse transcription polymerase chain reaction (qRT-PCR) revealed that CsEIL genes were widely expressed in different organs of sweet orange and responded to both high and low temperature, NaCl treatment, and to ethylene-dependent induction of transcription, while eight additionally responded to Xanthomonas citri pv. Citri (Xcc) infection, which causes citrus canker. Among these, CsEIL2, CsEIL5 and CsEIL10 showed pronounced upregulation. Moreover, nine genes exhibited differential expression in response to Candidatus Liberibacter asiaticus (CLas) infection, which causes Citrus Huanglongbing (HLB). The genome-wide characterization and expression profile analysis of CsEIL genes provide insights into the potential functions of the CsEIL family in disease resistance.
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Affiliation(s)
- Yajun Su
- National Citrus Improvement Center, Hunan Agricultural University (Changsha Branch), Changsha 410128, China
- College of Horticulture, Hunan Agricultural University, Changsha 410128, China
- College of Plant Protection, Hunan Agricultural University, Changsha 410128, China (X.W.)
| | - Suming Dai
- National Citrus Improvement Center, Hunan Agricultural University (Changsha Branch), Changsha 410128, China
- College of Horticulture, Hunan Agricultural University, Changsha 410128, China
| | - Na Li
- National Citrus Improvement Center, Hunan Agricultural University (Changsha Branch), Changsha 410128, China
- College of Horticulture, Hunan Agricultural University, Changsha 410128, China
| | - Alessandra Gentile
- Department of Agriculture and Food Science, University of Catania, 95123 Catania, Italy;
| | - Cong He
- National Citrus Improvement Center, Hunan Agricultural University (Changsha Branch), Changsha 410128, China
- College of Horticulture, Hunan Agricultural University, Changsha 410128, China
| | - Jing Xu
- College of Plant Protection, Hunan Agricultural University, Changsha 410128, China (X.W.)
| | - Kangle Duan
- College of Plant Protection, Hunan Agricultural University, Changsha 410128, China (X.W.)
| | - Xue Wang
- College of Plant Protection, Hunan Agricultural University, Changsha 410128, China (X.W.)
| | - Bing Wang
- College of Plant Protection, Hunan Agricultural University, Changsha 410128, China (X.W.)
| | - Dazhi Li
- National Citrus Improvement Center, Hunan Agricultural University (Changsha Branch), Changsha 410128, China
- College of Horticulture, Hunan Agricultural University, Changsha 410128, China
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10
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Alexandrino AV, Prieto EL, Nicolela NCS, da Silva Marin TG, Dos Santos TA, de Oliveira da Silva JPM, da Cunha AF, Behlau F, Novo-Mansur MTM. Xylose Isomerase Depletion Enhances Virulence of Xanthomonas citri subsp. citri in Citrus aurantifolia. Int J Mol Sci 2023; 24:11491. [PMID: 37511250 PMCID: PMC10380989 DOI: 10.3390/ijms241411491] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2023] [Revised: 04/14/2023] [Accepted: 04/17/2023] [Indexed: 07/30/2023] Open
Abstract
Citrus canker, caused by the bacterium Xanthomonas citri (Xcc), is one of the most devastating diseases for the citrus industry. Xylose is a constituent of the cell wall of plants, and the ability of Xcc to use this carbohydrate may play a role in virulence. Xcc has two genes codifying for xylose isomerase (XI), a bifunctional enzyme that interconverts D-xylose into D-xylulose and D-glucose into D-fructose. The aim of this work was to investigate the functional role of the two putative XI ORFs, XAC1776 (xylA1) and XAC4225 (xylA2), in Xcc pathogenicity. XI-coding genes of Xcc were deleted, and the single mutants (XccΔxylA1 or XccΔxylA2) or the double mutant (XccΔxylA1ΔxylA2) remained viable. The deletion of one or both XI genes (xylA1 and/or xylA2) increased the aggressiveness of the mutants, causing disease symptoms. RT-qPCR analysis of wild strain and xylA deletion mutants grown in vivo and in vitro revealed that the highest expression level of hrpX and xylR was observed in vivo for the double mutant. The results indicate that XI depletion increases the expression of the hrp regulatory genes in Xcc. We concluded that the intracellular accumulation of xylose enhances Xcc virulence.
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Affiliation(s)
- André Vessoni Alexandrino
- Laboratório de Bioquímica e Biologia Molecular Aplicada-LBBMA, Departamento de Genética e Evolução, Universidade Federal de São Carlos, São Carlos 13565-905, SP, Brazil
- Programa de Pós-Graduação em Biotecnologia-PPGBiotec, Universidade Federal de São Carlos, São Carlos 13565-905, SP, Brazil
| | - Evandro Luis Prieto
- Laboratório de Bioquímica e Biologia Molecular Aplicada-LBBMA, Departamento de Genética e Evolução, Universidade Federal de São Carlos, São Carlos 13565-905, SP, Brazil
- Programa de Pós-Graduação em Genética Evolutiva e Biologia Molecular-PPGGEv, Universidade Federal de São Carlos, São Carlos 13565-905, SP, Brazil
| | - Nicole Castro Silva Nicolela
- Laboratório de Bioquímica e Biologia Molecular Aplicada-LBBMA, Departamento de Genética e Evolução, Universidade Federal de São Carlos, São Carlos 13565-905, SP, Brazil
| | | | | | - João Pedro Maia de Oliveira da Silva
- Programa de Pós-Graduação em Genética Evolutiva e Biologia Molecular-PPGGEv, Universidade Federal de São Carlos, São Carlos 13565-905, SP, Brazil
- Laboratório de Bioquímica e Genética Aplicada-LBGA, Departamento de Genética e Evolução, Universidade Federal de São Carlos, São Carlos 13565-905, SP, Brazil
| | - Anderson Ferreira da Cunha
- Programa de Pós-Graduação em Genética Evolutiva e Biologia Molecular-PPGGEv, Universidade Federal de São Carlos, São Carlos 13565-905, SP, Brazil
- Laboratório de Bioquímica e Genética Aplicada-LBGA, Departamento de Genética e Evolução, Universidade Federal de São Carlos, São Carlos 13565-905, SP, Brazil
| | - Franklin Behlau
- Fundo de Defesa da Citricultura-Fundecitrus, Araraquara 14807-040, SP, Brazil
| | - Maria Teresa Marques Novo-Mansur
- Laboratório de Bioquímica e Biologia Molecular Aplicada-LBBMA, Departamento de Genética e Evolução, Universidade Federal de São Carlos, São Carlos 13565-905, SP, Brazil
- Programa de Pós-Graduação em Biotecnologia-PPGBiotec, Universidade Federal de São Carlos, São Carlos 13565-905, SP, Brazil
- Programa de Pós-Graduação em Genética Evolutiva e Biologia Molecular-PPGGEv, Universidade Federal de São Carlos, São Carlos 13565-905, SP, Brazil
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11
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de Souza-Neto RR, Vasconcelos FNDC, Teper D, Carvalho IGB, Takita MA, Benedetti CE, Wang N, de Souza AA. The Expansin Gene CsLIEXP1 Is a Direct Target of CsLOB1 in Citrus. Phytopathology 2023; 113:1266-1277. [PMID: 36825333 DOI: 10.1094/phyto-11-22-0424-r] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/18/2023]
Abstract
Transcription activator-like effectors are key virulence factors of Xanthomonas. They are secreted into host plant cells and mimic transcription factors inducing the expression of host susceptibility (S) genes. In citrus, CsLOB1 is a direct target of PthA4, the primary effector associated with citrus canker symptoms. CsLOB1 is a transcription factor, and its expression is required for canker symptoms induced by Xanthomonas citri subsp. citri. Several genes are up-regulated by PthA4; however, only CsLOB1 was described as an S gene induced by PthA4. Here, we investigated whether other up-regulated genes could be direct targets of PthA4 or CsLOB1. Seven up-regulated genes by PthA4 were investigated; however, an expansin-coding gene was more induced than CsLOB1. In Nicotiana benthamiana transient expression experiments, we demonstrate that the expansin-coding gene, referred here to as CsLOB1-INDUCED EXPANSIN 1 (CsLIEXP1), is not a direct target of PthA4, but CsLOB1. Interestingly, CsLIEXP1 was induced by CsLOB1 even without the predicted CsLOB1 binding site, which suggested that CsLOB1 has other unknown binding sites. We also investigated the minimum promoter regulated by CsLOB1, and this region and LOB1 domain were conserved among citrus species and relatives, which suggests that the interaction PthA4-CsLOB1-CsLIEXP1 is conserved in citrus species and relatives. This is the first study that experimentally demonstrated a CsLOB1 downstream target and lays the foundation to identify other new targets. In addition, we demonstrated that the CsLIEXP1 is a putative S gene indirectly induced by PthA4, which may serve as the target for genome editing to generate citrus canker-resistant varieties.
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Affiliation(s)
- Reinaldo Rodrigues de Souza-Neto
- Citrus Research Center "Sylvio Moreira", Agronomic Institute-IAC, Brazil
- Departament of Genetics, Evolution and Bioagents, Institute of Biology, University of Campinas, Brazil
| | | | - Doron Teper
- Department of Plant Pathology and Weed Research, Institute of Plant Protection, Agricultural Research Organization, Volcani Center, Israel
| | | | | | - Celso Eduardo Benedetti
- Brazilian Biosciences National Laboratory (LNBio), Brazilian Center for Research in Energy and Materials (CNPEM), Brazil
| | - Nian Wang
- Citrus Research and Education Center, Department of Microbiology and Cell Science, Institute of Food and Agricultural Sciences (IFAS), University of Florida, U.S.A
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12
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Zhang G, Li C, Li Y, Chen D, Li Z, Ouyang G, Wang Z. Discovery and Mechanism of Azatryptanthrin Derivatives as Novel Anti-Phytopathogenic Bacterial Agents for Potent Bactericide Candidates. J Agric Food Chem 2023; 71:6288-6300. [PMID: 37040536 DOI: 10.1021/acs.jafc.3c01120] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/03/2023]
Abstract
The natural alkaloids of tryptanthrin and their derivatives have a wide range of biological activities. In this research, four series of azatryptanthrin derivatives containing 4-aza/3-aza/2-aza/1-aza tryptanthrin were prepared by condensation cyclization reaction against plant pathogens to develop a new natural product-based bacterial pesticide. Compound 4Aza-8 displayed a remarkable growth inhibitory effect on pathogenic bacteria of Xanthomonas axonopodis pv. citri (Xac), Xanthomonas oryzae pv. Oryzae (Xoo), and Pseudomonas syringae pv. actinidiae (Psa) with the final corrected EC50 values of 0.312, 1.91, and 18.0 μg/mL, respectively, which were greatly superior than that of tryptanthrin (Tryp). Moreover, 4Aza-8 also showed effective therapeutic and protective activities in vivo on citrus canker. Further mechanism studies on Xac elucidated that compound 4Aza-8 was able to affect the growth curve of Xac and the formation of biofilm, cause severe shrinkage in bacterial morphology, increase reactive oxygen species levels, and induce apoptosis in bacterial cells. Quantitative analysis of differential protein profiles found that the major differences were mainly concentrated on the endometrial protein in the bacterial secretion system pathway, which blocked the membrane transport and affected the transfer of DNA to the host cell. In summary, these research results suggest that 4Aza-8 represents a promising anti-phytopathogenic-bacteria agent, which is worth being further investigated as a bactericide candidate.
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Affiliation(s)
- Guanglong Zhang
- 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
| | - Chengpeng Li
- School of Pharmaceutical Sciences, Guizhou University, Guiyang, Guizhou 550025, China
| | - Yan Li
- School of Pharmaceutical Sciences, Guizhou University, Guiyang, Guizhou 550025, China
| | - Danping Chen
- School of Pharmaceutical Sciences, Guizhou University, Guiyang, Guizhou 550025, China
| | - Zhuirui Li
- School of Pharmaceutical Sciences, Guizhou University, Guiyang, Guizhou 550025, China
| | - Guiping Ouyang
- 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
- School of Pharmaceutical Sciences, Guizhou University, Guiyang, Guizhou 550025, China
| | - Zhenchao Wang
- 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
- School of Pharmaceutical Sciences, Guizhou University, Guiyang, Guizhou 550025, China
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13
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Ragupathy R, Jolley KA, Zamuner C, Jones JB, Redfern J, Behlau F, Ferreira H, Enright MC. Core-Genome Multilocus Sequence Typing for Epidemiological and Evolutionary Analyses of Phytopathogenic Xanthomonas citri. Appl Environ Microbiol 2023; 89:e0210122. [PMID: 37067413 DOI: 10.1128/aem.02101-22] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/18/2023] Open
Abstract
Xanthomonas citri subsp. citri is the cause of bacterial citrus canker, responsible for major economic losses to the citrus industry. X. citri subspecies and pathovars are responsible for diseases in soybean, common bean, mango, pomegranate, and cashew. X. citri disease has been tracked using several typing methods, but recent studies using genomic sequencing have been key to understanding the evolutionary relationships within the species, including fundamental differences among X. citri subsp. citri pathotypes. Here, we describe a core-genome multilocus sequence typing (cgMLST) scheme for X. citri based on 250 genomes comprising multiple examples of X. citri subsp. citri pathotypes A, A*, and Aw; X. citri subsp. malvacearum; X. citri pv. aurantifolii, pv. fuscans, pv. glycines, pv. mangiferaeindicae, pv. viticola, and pv. vignicola; and single isolates of X. citri pv. dieffenbachiae and pv. punicae. This data set included genomic sequencing of 100 novel X. citri subsp. citri isolates. cgMLST, based on 1,618 core genes across 250 genomes, is implemented at PubMLST (https://pubmlst.org/organisms/xanthomonas-citri/). GrapeTree minimum-spanning tree and Interactive Tree of Life (iTOL) neighbor-joining phylogenies generated from the cgMLST data resolved almost identical groupings of isolates to a core-genome single nucleotide polymorphism (SNP)-based neighbor-joining phylogeny. These resolved identical groupings of X. citri subsp. citri pathotypes and X. citri subspecies and pathovars. X. citri cgMLST should prove to be an increasingly valuable resource for the study of this key species of plant-pathogenic bacteria. Users can submit genomic data and associated metadata for comparison with previously characterized isolates at PubMLST to allow the rapid characterization of the local, national, and global epidemiology of these pathogens and examine evolutionary relationships. IMPORTANCE Xanthomonas citri is a plant pathogen that causes major economic losses to the citrus industry and sweet orange production in particular. Several subspecies and pathogens are recognized, with host ranges including soybean, common bean, mango, pomegranate, and cashew, among others. Recent genomic studies have shown that host-adapted X. citri subspecies and pathovars and X. citri subsp. citri pathotypes form distinct clades. In this study, we describe a core-genome multilocus sequence typing (cgMLST) scheme for this species that can rapidly and robustly discriminate among these ecologically distinct, host-adapted clades. We have established this scheme and associated databases containing genomic sequences and metadata at PubMLST, which users can interrogate with their own genome sequences to determine X. citri subspecies, pathovars, and pathotypes. X. citri cgMLST should prove to be an invaluable tool for the study of the epidemiology and evolution of this major plant pathogen.
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Affiliation(s)
- R Ragupathy
- Department of Life Sciences, Manchester Metropolitan University, Manchester, United Kingdom
| | - K A Jolley
- Department of Biology, University of Oxford, Oxford, United Kingdom
| | - C Zamuner
- Departamento de Biologia Geral e Aplicada, Universidade Estadual Paulista, Rio Claro, São Paulo, Brazil
| | - J B Jones
- Department of Plant Pathology, University of Florida, Gainesville, Florida, USA
| | - J Redfern
- Department of Life Sciences, Manchester Metropolitan University, Manchester, United Kingdom
| | - F Behlau
- Fundecitrus, Araraquara, São Paulo, Brazil
| | - H Ferreira
- Departamento de Biologia Geral e Aplicada, Universidade Estadual Paulista, Rio Claro, São Paulo, Brazil
| | - M C Enright
- Department of Life Sciences, Manchester Metropolitan University, Manchester, United Kingdom
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14
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Gaurav I, Thakur A, Kumar G, Long Q, Zhang K, Sidu RK, Thakur S, Sarkar RK, Kumar A, Iyaswamy A, Yang Z. Delivery of Apoplastic Extracellular Vesicles Encapsulating Green-Synthesized Silver Nanoparticles to Treat Citrus Canker. Nanomaterials (Basel) 2023; 13:1306. [PMID: 37110891 PMCID: PMC10146377 DOI: 10.3390/nano13081306] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 01/03/2023] [Revised: 03/23/2023] [Accepted: 03/27/2023] [Indexed: 06/19/2023]
Abstract
The citrus canker pathogen Xanthomonas axonopodis has caused severe damage to citrus crops worldwide, resulting in significant economic losses for the citrus industry. To address this, a green synthesis method was used to develop silver nanoparticles with the leaf extract of Phyllanthus niruri (GS-AgNP-LEPN). This method replaces the need for toxic reagents, as the LEPN acts as a reducing and capping agent. To further enhance their effectiveness, the GS-AgNP-LEPN were encapsulated in extracellular vesicles (EVs), nanovesicles with a diameter of approximately 30-1000 nm naturally released from different sources, including plant and mammalian cells, and found in the apoplastic fluid (APF) of leaves. When compared to a regular antibiotic (ampicillin), the delivery of APF-EV-GS-AgNP-LEPN and GS-AgNP-LEPN to X. axonopodis pv. was shown to have more significant antimicrobial activity. Our analysis showed the presence of phyllanthin and nirurinetin in the LEPN and found evidence that both could be responsible for antimicrobial activity against X. axonopodis pv. Ferredoxin-NADP+ reductase (FAD-FNR) and the effector protein XopAI play a crucial role in the survival and virulence of X. axonopodis pv. Our molecular docking studies showed that nirurinetin could bind to FAD-FNR and XopAI with high binding energies (-10.32 kcal/mol and -6.13 kcal/mol, respectively) as compared to phyllanthin (-6.42 kcal/mol and -2.93 kcal/mol, respectively), which was also supported by the western blot experiment. We conclude that (a) the hybrid of APF-EV and GS-NP could be an effective treatment for citrus canker, and (b) it works via the nirurinetin-dependent inhibition of FAD-FNR and XopAI in X. axonopodis pv.
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Affiliation(s)
- Isha Gaurav
- School of Chinese Medicine, Hong Kong Baptist University, Hong Kong SAR 999077, China
| | - Abhimanyu Thakur
- Ben May Department for Cancer Research, Pritzker School of Molecular Engineering, University of Chicago, Chicago, IL 60637, USA
| | - Gaurav Kumar
- Clinical Research Division, Department of Biosciences, School of Basic and Applied Sciences, Galgotias University, Greater Noida 203201, Uttar Pradesh, India
| | - Qin Long
- Citrus Research Institute, Southwest University, Chinese Academy of Agricultural Sciences, National Citrus Engineering Research Center, Chongqing 400712, China
| | - Kui Zhang
- Ben May Department for Cancer Research, Pritzker School of Molecular Engineering, University of Chicago, Chicago, IL 60637, USA
| | - Rakesh Kumar Sidu
- School of Biomedical Engineering, Indian Institute of Technology, Banaras Hindu University, Varanasi 221005, Uttar Pradesh, India
| | - Sudha Thakur
- National Institute for Locomotor Disabilities (Divyangjan), Kolkata 700090, India
| | - Rajesh Kumar Sarkar
- Department of Medicine, Division of Biological Sciences, University of Chicago, Chicago, IL 60637, USA
| | - Anoop Kumar
- Department of Pharmacology, Delhi Pharmaceutical Sciences and Research University (DPSRU), New Delhi 110017, India
| | - Ashok Iyaswamy
- School of Chinese Medicine, Hong Kong Baptist University, Hong Kong SAR 999077, China
- Mr. & Mrs. Ko Chi-Ming Centre for Parkinson’s Disease Research, School of Chinese Medicine, Hong Kong Baptist University, Hong Kong SAR 999077, China
- Department of Biochemistry, Karpagam Academy of Higher Education, Coimbatore 641021, India
| | - Zhijun Yang
- School of Chinese Medicine, Hong Kong Baptist University, Hong Kong SAR 999077, China
- Changshu Research Institute, Hong Kong Baptist University, Changshu Economic and Technological Development (CETD) Zone, Changshu 215500, China
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15
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Andrade MDO, da Silva JC, Soprano AS, Shimo HM, Leme AFP, Benedetti CE. Suppression of citrus canker disease mediated by flagellin perception. Mol Plant Pathol 2023; 24:331-345. [PMID: 36691963 PMCID: PMC10013774 DOI: 10.1111/mpp.13300] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/04/2022] [Revised: 01/05/2023] [Accepted: 01/11/2023] [Indexed: 06/17/2023]
Abstract
Citrus cancer, caused by strains of Xanthomonas citri (Xc) and Xanthomonas aurantifolii (Xa), is one of the most economically important citrus diseases. Although our understanding of the molecular mechanisms underlying citrus canker development has advanced remarkably in recent years, exactly how citrus plants fight against these pathogens remains largely unclear. Using a Xa pathotype C strain that infects Mexican lime only and sweet oranges as a pathosystem to study the immune response triggered by this bacterium in these hosts, we herein report that the Xa flagellin C protein (XaFliC) acts as a potent defence elicitor in sweet oranges. Just as Xa blocked canker formation when coinfiltrated with Xc in sweet orange leaves, two polymorphic XaFliC peptides designated flgIII-20 and flgIII-27, not related to flg22 or flgII-28 but found in many Xanthomonas species, were sufficient to protect sweet orange plants from Xc infection. Accordingly, ectopic expression of XaFliC in a Xc FliC-defective mutant completely abolished the ability of this mutant to grow and cause canker in sweet orange but not Mexican lime plants. Because XaFliC and flgIII-27 also specifically induced the expression of several defence-related genes, our data suggest that XaFliC acts as a main immune response determinant in sweet orange plants.
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Affiliation(s)
- Maxuel de Oliveira Andrade
- Brazilian Biosciences National Laboratory (LNBio), Brazilian Center for Research in Energy and Materials (CNPEM)CampinasBrazil
| | - Jaqueline Cristina da Silva
- Brazilian Biosciences National Laboratory (LNBio), Brazilian Center for Research in Energy and Materials (CNPEM)CampinasBrazil
| | - Adriana Santos Soprano
- Brazilian Biosciences National Laboratory (LNBio), Brazilian Center for Research in Energy and Materials (CNPEM)CampinasBrazil
| | - Hugo Massayoshi Shimo
- Brazilian Biosciences National Laboratory (LNBio), Brazilian Center for Research in Energy and Materials (CNPEM)CampinasBrazil
| | - Adriana Franco Paes Leme
- Brazilian Biosciences National Laboratory (LNBio), Brazilian Center for Research in Energy and Materials (CNPEM)CampinasBrazil
| | - Celso Eduardo Benedetti
- Brazilian Biosciences National Laboratory (LNBio), Brazilian Center for Research in Energy and Materials (CNPEM)CampinasBrazil
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16
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Shahbaz E, Ali M, Shafiq M, Atiq M, Hussain M, Balal RM, Sarkhosh A, Alferez F, Sadiq S, Shahid MA. Citrus Canker Pathogen, Its Mechanism of Infection, Eradication, and Impacts. Plants (Basel) 2022; 12:plants12010123. [PMID: 36616252 PMCID: PMC9824702 DOI: 10.3390/plants12010123] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/11/2022] [Revised: 11/14/2022] [Accepted: 12/13/2022] [Indexed: 05/16/2023]
Abstract
Citrus canker is a ravaging bacterial disease threatening citrus crops. Its major types are Asiatic Canker, Cancrosis B, and Cancrosis C, caused by Xanthomonas citri pv. citri (Xcc), Xanthomonas citri pv. aurantifolii pathotype-B (XauB), and pathotype-C (XauC), respectively. The bacterium enters its host through stomata and wounds, from which it invades the intercellular spaces in the apoplast. It produces erumpent corky necrotic lesions often surrounded by a chlorotic halo on the leaves, young stems, and fruits, which causes dark spots, defoliation, reduced photosynthetic rate, rupture of leaf epidermis, dieback, and premature fruit drop in severe cases. Its main pathogenicity determinant gene is pthA, whose variants are present in all citrus canker-causing pathogens. Countries where citrus canker is not endemic adopt different methods to prevent the introduction of the pathogen into the region, eradicate the pathogen, and minimize its dissemination, whereas endemic regions require an integrated management program to control the disease. The main aim of the present manuscript is to shed light on the pathogen profile, its mechanism of infection, and fruitful strategies for disease management. Although an adequate method to completely eradicate citrus canker has not been introduced so far, many new methods are under research to abate the disease.
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Affiliation(s)
- Esha Shahbaz
- Department of Food Sciences, Faculty of Agricultural Sciences, University of the Punjab, Lahore 54590, Pakistan
| | - Mobeen Ali
- Department of Horticulture, Faculty of Agricultural Sciences, University of the Punjab, Lahore 54590, Pakistan
| | - Muhammad Shafiq
- Department of Horticulture, Faculty of Agricultural Sciences, University of the Punjab, Lahore 54590, Pakistan
| | - Muhammad Atiq
- Department of Plant Pathology, University of Agriculture, Faisalabad 38000, Pakistan
| | - Mujahid Hussain
- Horticultural Science Department, North Florida Research and Education Center, University of Florida/IFAS, Quincy, FL 32351, USA
| | - Rashad Mukhtar Balal
- Department of Horticulture, College of Agriculture, University of Sargodha, Sargodha 40100, Pakistan
| | - Ali Sarkhosh
- Horticultural Sciences Department, University of Florida, Gainesville, FL 32611, USA
| | - Fernando Alferez
- Horticultural Science Department, Southwest Florida Research and Education Center, University of Florida/IFAS, Immokalee, FL 34142, USA
| | - Saleha Sadiq
- Department of Horticulture, Faculty of Agricultural Sciences, University of the Punjab, Lahore 54590, Pakistan
| | - Muhammad Adnan Shahid
- Horticultural Science Department, North Florida Research and Education Center, University of Florida/IFAS, Quincy, FL 32351, USA
- Correspondence:
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Yadav PK, Burks T, Frederick Q, Qin J, Kim M, Ritenour MA. Citrus disease detection using convolution neural network generated features and Softmax classifier on hyperspectral image data. Front Plant Sci 2022; 13:1043712. [PMID: 36570926 PMCID: PMC9768035 DOI: 10.3389/fpls.2022.1043712] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 09/13/2022] [Accepted: 11/18/2022] [Indexed: 06/17/2023]
Abstract
Identification and segregation of citrus fruit with diseases and peel blemishes are required to preserve market value. Previously developed machine vision approaches could only distinguish cankerous from non-cankerous citrus, while this research focused on detecting eight different peel conditions on citrus fruit using hyperspectral (HSI) imagery and an AI-based classification algorithm. The objectives of this paper were: (i) selecting the five most discriminating bands among 92 using PCA, (ii) training and testing a custom convolution neural network (CNN) model for classification with the selected bands, and (iii) comparing the CNN's performance using 5 PCA bands compared to five randomly selected bands. A hyperspectral imaging system from earlier work was used to acquire reflectance images in the spectral region from 450 to 930 nm (92 spectral bands). Ruby Red grapefruits with normal, cankerous, and 5 other common peel diseases including greasy spot, insect damage, melanose, scab, and wind scar were tested. A novel CNN based on the VGG-16 architecture was developed for feature extraction, and SoftMax for classification. The PCA-based bands were found to be 666.15, 697.54, 702.77, 849.24 and 917.25 nm, which resulted in an average accuracy, sensitivity, and specificity of 99.84%, 99.84% and 99.98% respectively. However, 10 trials of five randomly selected bands resulted in only a slightly lower performance, with accuracy, sensitivity, and specificity of 98.87%, 98.43% and 99.88%, respectively. These results demonstrate that an AI-based algorithm can successfully classify eight different peel conditions. The findings reported herein can be used as a precursor to develop a machine vision-based, real-time peel condition classification system for citrus processing.
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Affiliation(s)
- Pappu Kumar Yadav
- Department of Agricultural and Biological Engineering, University of Florida, Gainesville, FL, United States
| | - Thomas Burks
- Department of Agricultural and Biological Engineering, University of Florida, Gainesville, FL, United States
| | - Quentin Frederick
- Department of Agricultural and Biological Engineering, University of Florida, Gainesville, FL, United States
| | - Jianwei Qin
- USDA/ARS Environmental Microbial and Food Safety Laboratory, Beltsville Agricultural Research Center, Beltsville, MD, United States
| | - Moon Kim
- USDA/ARS Environmental Microbial and Food Safety Laboratory, Beltsville Agricultural Research Center, Beltsville, MD, United States
| | - Mark A. Ritenour
- Department of Horticultural Sciences, University of Florida, Fort Pierce, FL, United States
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18
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Saldanha LL, Allard PM, Dilarri G, Codesido S, González-Ruiz V, Queiroz EF, Ferreira H, Wolfender JL. Metabolomic- and Molecular Networking-Based Exploration of the Chemical Responses Induced in Citrus sinensis Leaves Inoculated with Xanthomonas citri. J Agric Food Chem 2022; 70:14693-14705. [PMID: 36350271 DOI: 10.1021/acs.jafc.2c05156] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/16/2023]
Abstract
Citrus canker, caused by the bacterium Xanthomonas citri subsp. citri (X. citri), is a plant disease affecting Citrus crops worldwide. However, little is known about defense compounds in Citrus. Here, we conducted a mass spectrometry-based metabolomic approach to obtain an overview of the chemical responses of Citrus leaves to X. citri infection. To facilitate result interpretation, the multivariate analyses were combined with molecular networking to identify biomarkers. Metabolite variations among untreated and X. citri-inoculated Citrus samples under greenhouse conditions highlighted induced defense biomarkers. Notably, the plant tryptophan metabolism pathway was activated, leading to the accumulation of N-methylated tryptamine derivatives. This finding was subsequently confirmed in symptomatic leaves in the field. Several tryptamine derivatives showed inhibitory effects in vitro against X. citri. This approach has enabled the identification of new chemically related biomarker groups and their dynamics in the response of Citrus leaves to Xanthomonas infection.
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Affiliation(s)
- Luiz Leonardo Saldanha
- Biochemistry Building, Department of General and Applied Biology, Institute of Biosciences, State University of São Paulo, Rio Claro, 13506-900 São Paulo, Brazil
- Institute of Pharmaceutical Sciences of Western Switzerland, University of Geneva, 1211 Geneva 4, Switzerland
- School of Pharmaceutical Sciences, University of Geneva, 1211 Geneva 4, Switzerland
| | - Pierre-Marie Allard
- Institute of Pharmaceutical Sciences of Western Switzerland, University of Geneva, 1211 Geneva 4, Switzerland
- School of Pharmaceutical Sciences, University of Geneva, 1211 Geneva 4, Switzerland
- Departement of Biology, University of Fribourg, 1700 Fribourg, Switzerland
| | - Guilherme Dilarri
- Biochemistry Building, Department of General and Applied Biology, Institute of Biosciences, State University of São Paulo, Rio Claro, 13506-900 São Paulo, Brazil
| | - Santiago Codesido
- Institute of Pharmaceutical Sciences of Western Switzerland, University of Geneva, 1211 Geneva 4, Switzerland
- School of Pharmaceutical Sciences, University of Geneva, 1211 Geneva 4, Switzerland
| | - Víctor González-Ruiz
- Institute of Pharmaceutical Sciences of Western Switzerland, University of Geneva, 1211 Geneva 4, Switzerland
- School of Pharmaceutical Sciences, University of Geneva, 1211 Geneva 4, Switzerland
| | - Emerson Ferreira Queiroz
- Institute of Pharmaceutical Sciences of Western Switzerland, University of Geneva, 1211 Geneva 4, Switzerland
- School of Pharmaceutical Sciences, University of Geneva, 1211 Geneva 4, Switzerland
| | - Henrique Ferreira
- Biochemistry Building, Department of General and Applied Biology, Institute of Biosciences, State University of São Paulo, Rio Claro, 13506-900 São Paulo, Brazil
| | - Jean-Luc Wolfender
- Institute of Pharmaceutical Sciences of Western Switzerland, University of Geneva, 1211 Geneva 4, Switzerland
- School of Pharmaceutical Sciences, University of Geneva, 1211 Geneva 4, Switzerland
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19
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Long Y, Luo R, Xu Z, Cheng S, Li L, Ma H, Bao M, Li M, Ouyang Z, Wang N, Duan S. A Fluorescent Reporter-Based Evaluation Assay for Antibacterial Components Against Xanthomonas citri subsp. citri. Front Microbiol 2022; 13:864963. [PMID: 35602035 PMCID: PMC9114712 DOI: 10.3389/fmicb.2022.864963] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2022] [Accepted: 04/05/2022] [Indexed: 11/13/2022] Open
Abstract
Xanthomonas citri subsp. citri (Xcc) is the agent of citrus bacterial canker (CBC) disease, which has significantly reduced citrus quantity and quality in many producing areas worldwide. Copper-based bactericides are the primary products for CBC control and management, but the problems derived from copper-resistant and environmental contamination have become issues of anxiety. Thus, there is a need to find alternative antibacterial products instead of relying on a single type of agent. This study developed a method to evaluate the inhibition of antibacterial agents using the fluorescence-labeled recombinant Xcc strain (Xcc-eYFP). The optimization of timelines and parameters for the evaluation of antibacterial agents involved the use of a Spark™ multimode microplate reader. This evaluation and screening method can be applied to bactericides, cocktail-mixture formulations, antagonistic bacteria, and derived metabolites. The results showed that the minimum inhibitory concentration (MIC) of commercial bactericides determined by fluorescence agrees with the MIC values determined by the conventional method. A screened cocktail-mixture bactericide presents more activity than the individual agents during the protective effects. Notably, this method has been further developed in the screening of Xcc-antagonistic bacterial strains. In summary, we provide a validated strategy for screening and evaluation of different antibacterial components for inhibition against Xcc for CBC control and management.
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Affiliation(s)
- Yunfei Long
- China-USA Citrus Huanglongbing Joint Laboratory, National Navel Orange Engineering Research Center, Gannan Normal University, Ganzhou, China
| | - Ruifang Luo
- China-USA Citrus Huanglongbing Joint Laboratory, National Navel Orange Engineering Research Center, Gannan Normal University, Ganzhou, China
| | - Zhou Xu
- China-USA Citrus Huanglongbing Joint Laboratory, National Navel Orange Engineering Research Center, Gannan Normal University, Ganzhou, China
| | - Shuyuan Cheng
- China-USA Citrus Huanglongbing Joint Laboratory, National Navel Orange Engineering Research Center, Gannan Normal University, Ganzhou, China
| | - Ling Li
- China-USA Citrus Huanglongbing Joint Laboratory, National Navel Orange Engineering Research Center, Gannan Normal University, Ganzhou, China
| | - Haijie Ma
- College of Agricultural and Food Sciences, Zhejiang A&F University, Hangzhou, China
| | - Minli Bao
- China-USA Citrus Huanglongbing Joint Laboratory, National Navel Orange Engineering Research Center, Gannan Normal University, Ganzhou, China
| | - Min Li
- China-USA Citrus Huanglongbing Joint Laboratory, National Navel Orange Engineering Research Center, Gannan Normal University, Ganzhou, China
| | - Zhigang Ouyang
- China-USA Citrus Huanglongbing Joint Laboratory, National Navel Orange Engineering Research Center, Gannan Normal University, Ganzhou, China
| | - Nian Wang
- Department of Microbiology and Cell Science, Citrus Research and Education Center, University of Florida, Lake Alfred, FL, United States
| | - Shuo Duan
- China-USA Citrus Huanglongbing Joint Laboratory, National Navel Orange Engineering Research Center, Gannan Normal University, Ganzhou, China
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20
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Nascimento CA, Teixeira-Silva NS, Caserta R, Marques MOM, Takita MA, de Souza AA. Overexpression of CsSAMT in Citrus sinensis Induces Defense Response and Increases Resistance to Xanthomonas citri subsp. citri. Front Plant Sci 2022; 13:836582. [PMID: 35401588 PMCID: PMC8988300 DOI: 10.3389/fpls.2022.836582] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 12/15/2021] [Accepted: 03/04/2022] [Indexed: 06/14/2023]
Abstract
Citrus canker is a destructive disease caused by Xanthomonas citri subsp. citri, which affects all commercial sweet orange (Citrus sinensis [L.] Osbeck) cultivars. Salicylic acid (SA) and systemic-acquired resistance (SAR) have been demonstrated to have a crucial role in mediating plant defense responses against this phytopathogen. To induce SAR, SA is converted to methyl salicylate (MeSA) by an SA-dependent methyltransferase (SAMT) and translocated systemically to prime noninfected distal tissues. Here, we generated sweet orange transgenic plants (based on cvs. Hamlin and Valencia) overexpressing the SAMT gene from Citrus (CsSAMT) and evaluated their resistance to citrus canker. We obtained four independent transgenic lines and confirmed their significantly higher MeSA volatilization compared to wild-type controls. Plants overexpressing CsSAMT showed reduced symptoms of citrus canker and bacterial populations in all transgenic lines without compromising plant development. One representative transgenic line (V44SAMT) was used to evaluate resistance response in primary and secondary sites. Without inoculation, V44SAMT modulated CsSAMT, CsNPR1, CsNPR3, and CsWRKY22 expression, indicating that this plant is in a primed defense status. The results demonstrate that MeSA signaling prompts the plant to respond more efficiently to pathogen attacks and induces immune responses in transgenic plants at both primary and secondary infection sites.
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Affiliation(s)
- Cesar Augusto Nascimento
- Citrus Research Center “Sylvio Moreira”, Agronomic Institute – IAC, Cordeirópolis, Brazil
- Department of Genetics, Evolution and Bioagents, Institute of Biology, University of Campinas – UNICAMP, Campinas, Brazil
| | | | - Raquel Caserta
- Citrus Research Center “Sylvio Moreira”, Agronomic Institute – IAC, Cordeirópolis, Brazil
| | | | - Marco Aurelio Takita
- Citrus Research Center “Sylvio Moreira”, Agronomic Institute – IAC, Cordeirópolis, Brazil
| | - Alessandra A. de Souza
- Citrus Research Center “Sylvio Moreira”, Agronomic Institute – IAC, Cordeirópolis, Brazil
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21
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Wang X, Liang L, Shao H, Ye X, Yang X, Chen X, Shi Y, Zhang L, Xu L, Wang J. Isolation of the Novel Strain Bacillus amyloliquefaciens F9 and Identification of Lipopeptide Extract Components Responsible for Activity against Xanthomonas citri subsp. citri. Plants (Basel) 2022; 11:457. [PMID: 35161438 PMCID: PMC8840523 DOI: 10.3390/plants11030457] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 12/31/2021] [Revised: 01/24/2022] [Accepted: 02/05/2022] [Indexed: 06/14/2023]
Abstract
Citrus canker, caused by Xanthomonas citri subsp. citri (Xcc), is a quarantine disease that seriously affects citrus production worldwide. The use of microorganisms and their products for biological control has been proven to be effective in controlling Xanthomonas disease. In this study, a novel Xcc antagonistic strain was isolated and identified as Bacillus amyloliquefaciens F9 by morphological and molecular analysis. The lipopeptide extract of B. amyloliquefaciens F9 (F9LE) effectively inhibited the growth of Xcc in an agar diffusion assay and restrained the occurrence of canker lesions in a pathogenicity test under greenhouse conditions. Consistent with these findings, F9LE treatment significantly inhibited the production of extracellular enzymes in Xcc cells and induced cell wall damage, with leakage of bacterial contents revealed by scanning electron microscopy and transmission electron microscopy analyses. In addition, F9LE also showed strong antagonistic activity against a wide spectrum of plant pathogenic bacteria and fungi. Furthermore, using electrospray ionization mass spectrometry analysis, the main antimicrobial compounds of strain F9 were identified as three kinds of lipopeptides, including homologues of surfactin, fengycin, and iturin. Taken together, our results show that B. amyloliquefaciens F9 and its lipopeptide components have the potential to be used as biocontrol agents against Xcc, and other plant pathogenic bacteria and fungi.
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Affiliation(s)
- Xin Wang
- Integrative Microbiology Research Centre, College of Plant Protection, South China Agricultural University, Guangzhou 510642, China; (X.W.); (L.L.); (H.S.); (X.Y.); (X.Y.); (X.C.); (Y.S.); (L.Z.)
| | - Liqiong Liang
- Integrative Microbiology Research Centre, College of Plant Protection, South China Agricultural University, Guangzhou 510642, China; (X.W.); (L.L.); (H.S.); (X.Y.); (X.Y.); (X.C.); (Y.S.); (L.Z.)
| | - Hang Shao
- Integrative Microbiology Research Centre, College of Plant Protection, South China Agricultural University, Guangzhou 510642, China; (X.W.); (L.L.); (H.S.); (X.Y.); (X.Y.); (X.C.); (Y.S.); (L.Z.)
| | - Xiaoxin Ye
- Integrative Microbiology Research Centre, College of Plant Protection, South China Agricultural University, Guangzhou 510642, China; (X.W.); (L.L.); (H.S.); (X.Y.); (X.Y.); (X.C.); (Y.S.); (L.Z.)
| | - Xiaobei Yang
- Integrative Microbiology Research Centre, College of Plant Protection, South China Agricultural University, Guangzhou 510642, China; (X.W.); (L.L.); (H.S.); (X.Y.); (X.Y.); (X.C.); (Y.S.); (L.Z.)
| | - Xiaoyun Chen
- Integrative Microbiology Research Centre, College of Plant Protection, South China Agricultural University, Guangzhou 510642, China; (X.W.); (L.L.); (H.S.); (X.Y.); (X.Y.); (X.C.); (Y.S.); (L.Z.)
| | - Yu Shi
- Integrative Microbiology Research Centre, College of Plant Protection, South China Agricultural University, Guangzhou 510642, China; (X.W.); (L.L.); (H.S.); (X.Y.); (X.Y.); (X.C.); (Y.S.); (L.Z.)
| | - Lianhui Zhang
- Integrative Microbiology Research Centre, College of Plant Protection, South China Agricultural University, Guangzhou 510642, China; (X.W.); (L.L.); (H.S.); (X.Y.); (X.Y.); (X.C.); (Y.S.); (L.Z.)
- Guangdong Province Key Laboratory of Microbial Signals and Disease Control, South China Agricultural University, Guangzhou 510642, China
| | - Linghui Xu
- Integrative Microbiology Research Centre, College of Plant Protection, South China Agricultural University, Guangzhou 510642, China; (X.W.); (L.L.); (H.S.); (X.Y.); (X.Y.); (X.C.); (Y.S.); (L.Z.)
- Guangdong Province Key Laboratory of Microbial Signals and Disease Control, South China Agricultural University, Guangzhou 510642, China
| | - Junxia Wang
- Integrative Microbiology Research Centre, College of Plant Protection, South China Agricultural University, Guangzhou 510642, China; (X.W.); (L.L.); (H.S.); (X.Y.); (X.Y.); (X.C.); (Y.S.); (L.Z.)
- Guangdong Province Key Laboratory of Microbial Signals and Disease Control, South China Agricultural University, Guangzhou 510642, China
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22
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Abstract
Citrus canker caused by Xanthomonas citri subsp. citri is one of the most devastating citrus diseases worldwide. Generating disease-resistant citrus varieties is considered one of the most efficient and environmentally friendly measures for controlling canker. X. citri subsp. citri causes canker symptoms by inducing the expression of canker susceptibility gene LOB1 via PthA4, a transcription activator-like (TAL) effector, by binding to the effector binding element (EBE) in the promoter region. In previous studies, canker-resistant plants were generated by mutating the coding region or the EBE of LOB1. However, homozygous or biallelic canker-resistant plants have not been generated for commercial citrus varieties, such as grapefruit (Citrus paradisi), which usually contain two alleles of LOB1 and thus, have two types of LOB1 promoter sequences: TI LOBP and TII LOBP. Two different sgRNAs were used to target both EBE types. Both 35S promoter and Yao promoter were used to drive the expression of SpCas9p to modify EBEPthA4-LOBP in grapefruit. Using 'Duncan' grapefruit epicotyls as explants, 19 genome-edited grapefruit plants were generated with one biallelic mutant line (#DunYao7). X. citri subsp. citri caused canker symptoms on wild-type and nonbiallelic mutant plants but not on #DunYao7. XccPthA4 mutant containing the designer TAL effector dLOB1.5, which recognizes a conserved sequence in both wild-type and #DunYao7, caused canker symptoms on both wild-type and #DunYao7. No off-target mutations were detected in #DunYao7. This study represents the first time that CRISPR-mediated genome editing has been successfully used to generate disease-resistant plants for 'Duncan' grapefruit, paving the way for using disease-resistant varieties to control canker.
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Affiliation(s)
- Hongge Jia
- Citrus Research and Education Center, Department of Microbiology and Cell Science, Institute of Food and Agricultural Sciences, University of Florida, Lake Alfred 33850, U.S.A
| | - Ahmad A Omar
- Citrus Research and Education Center, Institute of Food and Agricultural Sciences, University of Florida, Lake Alfred 33850, U.S.A
- Biochemistry Department, Faculty of Agriculture, Zagazig University, Zagazig 44519, Egypt
| | - Vladimir Orbović
- Citrus Research and Education Center, Institute of Food and Agricultural Sciences, University of Florida, Lake Alfred 33850, U.S.A
| | - Nian Wang
- Citrus Research and Education Center, Department of Microbiology and Cell Science, Institute of Food and Agricultural Sciences, University of Florida, Lake Alfred 33850, U.S.A
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23
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Li W, Li Z, Zhang L, Deng X, Zheng Z. Genome Sequence Resource of Xanthomonas citri pv. citri from Formalin-Fixed Citrus Leaves Specimen Showing Canker Lesions Collected in 1982. Plant Dis 2022; 106:304-306. [PMID: 34328361 DOI: 10.1094/pdis-05-21-1100-a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
Xanthomonas citri pv. citri is the causative agent of citrus canker, one of the most devastating diseases threatening global citrus production. Here, we present the genome sequence of X. citri pv. citri strain GD82 from a formalin-fixed citrus leaf specimen showing canker lesions collected in 1982 in Guangdong Province, China. The GD82 genome consisted of 5,197,217 bp with G+C content of 64.8%, along with four circular plasmids: pXAC33 (32,377 bp), pXAC64 (63,972 bp), pXAC47 (47,810 bp), and pGD82.1 (219,560 bp). This is the oldest X. citri pv. citri genome from historical citrus canker specimens in China, which will enrich the current X. citri pv. citri genome database and facilitate genomic evolution research of X. citri pv. citri.
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Affiliation(s)
- Wenting Li
- Guangdong Province Key Laboratory of Microbial Signals and Disease Control, South China Agricultural University, Guangzhou, China
| | - Zhenxi Li
- Guangdong Province Key Laboratory of Microbial Signals and Disease Control, South China Agricultural University, Guangzhou, China
| | - Ling Zhang
- Guangdong Province Key Laboratory of Microbial Signals and Disease Control, South China Agricultural University, Guangzhou, China
| | - Xiaoling Deng
- Guangdong Province Key Laboratory of Microbial Signals and Disease Control, South China Agricultural University, Guangzhou, China
| | - Zheng Zheng
- Guangdong Province Key Laboratory of Microbial Signals and Disease Control, South China Agricultural University, Guangzhou, China
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24
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Smith SL, Campos MGN, Ozcan A, Mendis HC, Young M, Myers ME, Atilola M, Doomra M, Thwin Z, Johnson EG, Santra S. Multifunctional Surface, Subsurface, and Systemic Therapeutic (MS3T) Formulation for the Control of Citrus Canker. J Agric Food Chem 2021; 69:10807-10818. [PMID: 34505777 DOI: 10.1021/acs.jafc.1c03323] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
A multifunctional surface, subsurface and systemic therapeutic (MS3T) formulation comprised of two bactericides, both didecyldimethylammonium chloride (DDAC) and a zinc (Zn)-chelate, was developed as an alternative to copper pesticides for crop protection. Agricultural grade chemicals were used to prepare MS3T formulations. Minimal inhibitory concentration (MIC) was determined to be tested in vitro against Xanthomonas alfalfae subsp. citrumelonis (herein called Xa), Escherichia coli (E. coli), and Pseudomonas syringae (Ps). Assessment of the phytotoxic potential was carried out on tomato under greenhouse conditions. Moreover, field trials were conducted during three consecutive years on grapefruit (Chrysopelea paradise) groves to evaluate efficacy against citrus canker (Xanthomonas citri subsp. citri), scab (Elsinoe fawcetti), and melanose (Diaporthe citri). In addition to disease control, improvements to both fruit yield and quality were observed likely due to the nutritional activity of MS3T via the sustained release of plant nutrients (Zn and nitrogen). Zn residues of leaf tissues were analyzed via atomic absorption spectroscopy (AAS) at various time points before and after MS3T foliar applications throughout the duration of the 2018 field trial. Field trial results demonstrated MS3T to be an effective alternative to copper (Cu)-based formulations for the control of citrus canker.
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Affiliation(s)
| | | | | | | | | | - Monty E Myers
- Indian River Research and Education Center, University of Florida, 2199 South Rock Road, Fort Pierce, Florida 34945, United States
| | | | | | | | - Evan G Johnson
- Citrus Research and Education Center, University of Florida, 700 Experiment Station Road, Lake Alfred, Florida 33850, United States
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25
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Mitre LK, Teixeira‐Silva NS, Rybak K, Magalhães DM, de Souza‐Neto RR, Robatzek S, Zipfel C, de Souza AA. The Arabidopsis immune receptor EFR increases resistance to the bacterial pathogens Xanthomonas and Xylella in transgenic sweet orange. Plant Biotechnol J 2021; 19:1294-1296. [PMID: 33991397 PMCID: PMC8313127 DOI: 10.1111/pbi.13629] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/30/2021] [Accepted: 05/06/2021] [Indexed: 05/22/2023]
Affiliation(s)
- Letícia Kuster Mitre
- Centro de Citricultura Sylvio Moreira – IACCordeirópolisSPBrazil
- University of CampinasCampinasSPBrazil
| | | | - Katarzyna Rybak
- LMU BiocenterLudwig‐Maximilians‐Universität MünchenMartinsriedGermany
| | - Diogo Maciel Magalhães
- Centro de Citricultura Sylvio Moreira – IACCordeirópolisSPBrazil
- University of CampinasCampinasSPBrazil
| | | | - Silke Robatzek
- LMU BiocenterLudwig‐Maximilians‐Universität MünchenMartinsriedGermany
| | - Cyril Zipfel
- Institute of Plant and Microbial Biology and Zürich‐Basel Plant Science CenterUniversity of ZürichZürichSwitzerland
- The Sainsbury LaboratoryUniversity of East AngliaNorwich Research Park, NorwichUK
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26
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Zou X, Du M, Liu Y, Wu L, Xu L, Long Q, Peng A, He Y, Andrade M, Chen S. CsLOB1 regulates susceptibility to citrus canker through promoting cell proliferation in citrus. Plant J 2021; 106:1039-1057. [PMID: 33754403 DOI: 10.1111/tpj.15217] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/30/2020] [Revised: 02/18/2021] [Accepted: 02/23/2021] [Indexed: 05/25/2023]
Abstract
Citrus sinensis lateral organ boundary 1 (CsLOB1) was previously identified as a critical disease susceptibility gene for citrus bacterial canker, which is caused by Xanthomonas citri subsp. citri (Xcc). However, the molecular mechanisms of CsLOB1 in citrus response to Xcc are still elusive. Here, we constructed transgenic plants overexpressing and RNAi-silencing of CsLOB1 using the canker-disease susceptible 'wanjincheng' orange (C. sinensis Osbeck) as explants. CsLOB1-overexpressing plants exhibited dwarf phenotypes with smaller and thicker leaf, increased branches and adventitious buds clustered on stems. These phenotypes were followed by a process of pustule- and canker-like development that exhibited enhanced cell proliferation. Pectin depolymerization and expansin accumulation were enhanced by CsLOB1 overexpression, while cellulose and hemicellulose synthesis were increased by CsLOB1 silence. Whilst overexpression of CsLOB1 increased susceptibility, RNAi-silencing of CsLOB1 enhanced resistance to canker disease without impairing pathogen entry. Transcriptome analysis revealed that CsLOB1 positively regulated cell wall degradation and modification processes, cytokinin metabolism, and cell division. Additionally, 565 CsLOB1-targeted genes were identified in chromatin immunoprecipitation-sequencing (ChIP-seq) experiments. Motif discovery analysis revealed that the most highly overrepresented binding sites had a conserved 6-bp 'GCGGCG' consensus DNA motif. RNA-seq and ChIP-seq data suggested that CsLOB1 directly activates the expression of four genes involved in cell wall remodeling, and three genes that participate in cytokinin and brassinosteroid hormone pathways. Our findings indicate that CsLOB1 promotes cell proliferation by mechanisms depending on cell wall remodeling and phytohormone signaling, which may be critical to citrus canker development and bacterial growth in citrus.
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Affiliation(s)
- Xiuping Zou
- Citrus Research Institute, Chinese Academy of Agricultural Sciences/Southwest University, Chongqing, 400712, P. R. China
| | - Meixia Du
- Citrus Research Institute, Chinese Academy of Agricultural Sciences/Southwest University, Chongqing, 400712, P. R. China
| | - Yunuo Liu
- Citrus Research Institute, Chinese Academy of Agricultural Sciences/Southwest University, Chongqing, 400712, P. R. China
| | - Liu Wu
- Citrus Research Institute, Chinese Academy of Agricultural Sciences/Southwest University, Chongqing, 400712, P. R. China
| | - Lanzhen Xu
- Citrus Research Institute, Chinese Academy of Agricultural Sciences/Southwest University, Chongqing, 400712, P. R. China
| | - Qin Long
- Citrus Research Institute, Chinese Academy of Agricultural Sciences/Southwest University, Chongqing, 400712, P. R. China
| | - Aihong Peng
- Citrus Research Institute, Chinese Academy of Agricultural Sciences/Southwest University, Chongqing, 400712, P. R. China
| | - Yongrui He
- Citrus Research Institute, Chinese Academy of Agricultural Sciences/Southwest University, Chongqing, 400712, P. R. China
| | - Maxuel Andrade
- Brazilian Biosciences National Laboratory (LNBio), Brazilian Center for Research in Energy and Materials (CNPEM), Campinas, SP, Brazil
| | - Shanchun Chen
- Citrus Research Institute, Chinese Academy of Agricultural Sciences/Southwest University, Chongqing, 400712, P. R. China
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Martins PMM, Wood TK, de Souza AA. Persister Cells Form in the Plant Pathogen Xanthomonas citri subsp. citri under Different Stress Conditions. Microorganisms 2021; 9:microorganisms9020384. [PMID: 33672822 PMCID: PMC7918609 DOI: 10.3390/microorganisms9020384] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/24/2020] [Revised: 02/05/2021] [Accepted: 02/08/2021] [Indexed: 12/16/2022] Open
Abstract
Citrus canker disease, caused by the bacterium Xanthomonas citri subsp. citri is a constant threat to citrus-producing areas. Since it has no cure, agricultural practices to restrain its dissemination are essential to reduce the economic damage. Hence, increased knowledge of the basic aspects of X. citri biology could lead to more efficient management practices that can eliminate dormant bacteria in the field. The dormant cells, also referred to as persisters, are phenotypic variants with lowered metabolism, which in turn leads to tolerance to antimicrobials and undermines existing control approaches. We show here that X. citri forms persisters, identifying triggers for this phenotype, including antibiotics, high temperature, and metals (copper and zinc), which increase persistence rates by 10–100 times. The antioxidant N-acetylcysteine reduced copper and zinc-induced persisters, but not those induced by tetracycline, indicating that oxidative stress may be an important inducer of X. citri persistence. In addition, we found that metabolism-independent drugs like cisplatin and mitomycin C are able to eliminate X. citri persistent cells, as well as copper, at high concentrations. Specific amino acids like proline and isoleucine interfered with the physiological balance of the dormancy in X. citri, stimulating or preventing persister resuscitation. Taken together, we discover chemicals that can induce, wake, and kill X. citri persister cells; these results provide insights that should be considered for more efficient integrated control management in the field.
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Affiliation(s)
- Paula M. M. Martins
- Department of Chemical Engineering, Pennsylvania State University, University Park, PA 16802, USA;
- Biotechnology Laboratory, Centro de Citricultura Sylvio Moreira, Instituto Agronômico de Campinas, Rodovia Anhanguera Km 158, Cordeirópolis-SP 13490-000, Brazil
| | - Thomas K. Wood
- Department of Chemical Engineering, Pennsylvania State University, University Park, PA 16802, USA;
- Correspondence: (T.K.W.); (A.A.d.S.)
| | - Alessandra A. de Souza
- Biotechnology Laboratory, Centro de Citricultura Sylvio Moreira, Instituto Agronômico de Campinas, Rodovia Anhanguera Km 158, Cordeirópolis-SP 13490-000, Brazil
- Correspondence: (T.K.W.); (A.A.d.S.)
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Bueno D, Pedrolli DB, Martins PMM, Bocchini DA, Moraes KCM, Facincani AP, Ferro JA, Varani AM, Pena MM, Ferreira H. Riboswitch theo/ metE as a Transcription Regulation Tool for Xanthomonas citri subsp. citri. Microorganisms 2021; 9:329. [PMID: 33562149 DOI: 10.3390/microorganisms9020329] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2021] [Revised: 01/30/2021] [Accepted: 02/02/2021] [Indexed: 11/17/2022] Open
Abstract
: Xanthomonas citri subsp. citri (X. citri) is the causal agent of Asiatic Citrus Canker (ACC), a disease that affects citrus. ACC has no cure, and growers must rely on special agricultural practices to prevent bacterial spreading. Understanding X. citri basic biology is essential to foresee potential genetic targets to control ACC. Traditionally, microbial genetics use gene deletion/disruption to investigate gene function. However, essential genes are difficult to study this way. Techniques based on small-RNAs and antisense-RNAs are powerful for gene characterization, but not yet fully explored in prokaryotes. One alternative is riboswitches, which derive from bacteria, and can control transcription/translation. Riboswitches are non-coding RNAs able to modulate gene expression in the presence of specific ligands. Here we demonstrate that the riboswitch theo/metE decreases parB expression in X. citri in a platform responsive to theophylline. By monitoring cell respiration, we showed that higher concentrations of the ligand interfered with bacterial viability. Therefore, we determined the safe dose of theophylline to be used with X. citri. Finally, in downstream investigations of parB transcription modulation, we show evidence for the fact that ParB is stable, remains functional throughout the cell cycle, and is inherited by the daughter cells upon cell division.
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Lyu S, Chen G, Pan D, Chen J, She W. Molecular Analysis of 14-3-3 Genes in Citrus sinensis and Their Responses to Different Stresses. Int J Mol Sci 2021; 22:E568. [PMID: 33430069 DOI: 10.3390/ijms22020568] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2020] [Revised: 01/04/2021] [Accepted: 01/05/2021] [Indexed: 12/31/2022] Open
Abstract
14-3-3 proteins (14-3-3s) are among the most important phosphorylated molecules playing crucial roles in regulating plant development and defense responses to environmental constraints. No report thus far has documented the gene family of 14-3-3s in Citrus sinensis and their roles in response to stresses. In this study, nine 14-3-3 genes, designated as CitGF14s (CitGF14a through CitGF14i) were identified from the latest C. sinensis genome. Phylogenetic analysis classified them into ε-like and non-ε groups, which were supported by gene structure analysis. The nine CitGF14s were located on five chromosomes, and none had duplication. Publicly available RNA-Seq raw data and microarray databases were mined for 14-3-3 expression profiles in different organs of citrus and in response to biotic and abiotic stresses. RT-qPCR was used for further examining spatial expression patterns of CitGF14s in citrus and their temporal expressions in one-year-old C. sinensis “Xuegan” plants after being exposed to different biotic and abiotic stresses. The nine CitGF14s were expressed in eight different organs with some isoforms displayed tissue-specific expression patterns. Six of the CitGF14s positively responded to citrus canker infection (Xanthomonas axonopodis pv. citri). The CitGF14s showed expressional divergence after phytohormone application and abiotic stress treatments, suggesting that 14-3-3 proteins are ubiquitous regulators in C. sinensis. Using the yeast two-hybrid assay, CitGF14a, b, c, d, g, and h were found to interact with CitGF14i proteins to form a heterodimer, while CitGF14i interacted with itself to form a homodimer. Further analysis of CitGF14s co-expression and potential interactors established a 14-3-3s protein interaction network. The established network identified 14-3-3 genes and several candidate clients which may play an important role in developmental regulation and stress responses in this important fruit crop. This is the first study of 14-3-3s in citrus, and the established network may help further investigation of the roles of 14-3-3s in response to abiotic and biotic constraints.
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Li Y, Lin X, Hu J, Shuai J, Wei Y, He D. Synthesis and biological evaluation of stilbene-based peptoid mimics against the phytopathogenic bacterium Xanthomonas citri pv. citri. Pest Manag Sci 2021; 77:343-353. [PMID: 32741107 DOI: 10.1002/ps.6024] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/24/2020] [Revised: 07/26/2020] [Accepted: 08/01/2020] [Indexed: 06/11/2023]
Abstract
BACKGROUND The emergence of drug-resistant phytopathogenic bacteria and the need for new types of biological disease-control agents have accelerated efforts toward searching for alternative candidates with a low propensity for resistance development. In this study, a new series of stilbene-based peptoid mimics were synthesized, and their biological activities were evaluated against citrus pathogenic bacteria in vitro and in vivo. RESULTS Antibacterial bioassay results showed that the dicationic peptoid mimics 9a and 9b displayed excellent bioactivity against Xanthomonas citri pv. citri, with the minimum inhibitory concentration values of 25 μM, which were superior to those of commercial copper biocides Delite (200 μM) and Kasumin Bordeaux (100 μM). In vivo bioassay further confirmed their control efficacy against plant bacterial diseases. In addition, the antibacterial mechanism of action elucidated their membrane-disruption effects resulting in the leakage of the bacterial membranes, which was similar to that of antimicrobial peptides. Moreover, the inhibition effect on biofilm formation of peptoid mimics has also been demonstrated. CONCLUSION Stilbene-based peptoid mimics synthesized in this study showed promising antibacterial activity with a potent membrane-disruptive mechanism. The results suggested that stilbene-based peptoid mimics have the potential as a candidate new type of bactericide for citrus disease protection.
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Affiliation(s)
- Yan Li
- School of Chemistry and Chemical Engineering, South China University of Technology, Guangzhou, 510640, China
| | - Xingdong Lin
- School of Chemistry and Chemical Engineering, South China University of Technology, Guangzhou, 510640, China
| | - Jianqing Hu
- School of Chemistry and Chemical Engineering, South China University of Technology, Guangzhou, 510640, China
| | - Jianbo Shuai
- School of Chemistry and Chemical Engineering, South China University of Technology, Guangzhou, 510640, China
| | - Yinan Wei
- Department of Chemistry, College of Arts and Sciences, University of Kentucky, Lexington, Kentucky, 40506, USA
| | - Daohang He
- School of Chemistry and Chemical Engineering, South China University of Technology, Guangzhou, 510640, China
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Richard D, Pruvost O, Balloux F, Boyer C, Rieux A, Lefeuvre P. Time-calibrated genomic evolution of a monomorphic bacterium during its establishment as an endemic crop pathogen. Mol Ecol 2020; 30:1823-1835. [PMID: 33305421 DOI: 10.1111/mec.15770] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2020] [Revised: 11/30/2020] [Accepted: 12/03/2020] [Indexed: 01/03/2023]
Abstract
Horizontal gene transfer is of major evolutionary importance as it allows for the redistribution of phenotypically important genes among lineages. Such genes with essential functions include those involved in resistance to antimicrobial compounds and virulence factors in pathogenic bacteria. Understanding gene turnover at microevolutionary scales is critical to assess the pace of this evolutionary process. Here, we characterized and quantified gene turnover for the epidemic lineage of a bacterial plant pathogen of major agricultural importance worldwide. Relying on a dense geographic sampling spanning 39 years of evolution, we estimated both the dynamics of single nucleotide polymorphism accumulation and gene content turnover. We identified extensive gene content variation among lineages even at the smallest phylogenetic and geographic scales. Gene turnover rate exceeded nucleotide substitution rate by three orders of magnitude. Accessory genes were found preferentially located on plasmids, but we identified a highly plastic chromosomal region hosting ecologically important genes such as transcription activator-like effectors. Whereas most changes in the gene content are probably transient, the rapid spread of a mobile element conferring resistance to copper compounds widely used for the management of plant bacterial pathogens illustrates how some accessory genes can become ubiquitous within a population over short timeframes.
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Affiliation(s)
- Damien Richard
- Cirad, UMR PVBMT, Réunion, France.,ANSES, Plant Health Laboratory, Réunion, France.,Université de la Réunion, UMR PVBMT, Réunion, France
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Jiang L, Liu Y, Xu X, Su D, Zou H, Liu J, Yuan C, Huang M. Inhibition of the Citrus Canker Pathogen Using a Photosensitizer Assisted by Sunlight Irradiation. Front Microbiol 2020; 11:571691. [PMID: 33281768 PMCID: PMC7705355 DOI: 10.3389/fmicb.2020.571691] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2020] [Accepted: 09/16/2020] [Indexed: 12/16/2022] Open
Abstract
Citrus canker, induced by bacterial infection, seriously affects the growth and productivity of citrus around the world and has attracted strong research interest. The current treatment for this disease uses copper salts to inactivate the pathogenic bacteria: Xanthomonas citri subsp. citri (Xcc) strain. However, copper salts may have a negative impact on the environment or plant. In this work, we identify a chemical compound, 2,6-diiodo-1,3,5,7-tetramethyl-8-(P-benzoic acid)-4,4′-difluoroboradiazaindacene (DIBDP), to inactivate the pathogenic Xcc strain (29-1). DIBDP is activated by sunlight and generates reactive oxygen species to kill the bacteria. In order to overcome the degradation of DIBDP under sunlight, an adjuvant agent was identified to limit the photodegradation of DIBDP by forming a photosensitizer complex (PSC). This complex demonstrated significant antimicrobial activity to Xcc 29-1, which was 64-fold more potent than the copper biocides. The antimicrobial efficacy of PSC on citrus leaves infected by Xcc 29-1 also was much stronger than copper agent and, at the same time, the PSC was safe to the host exposed to sunlight. Thus, this PSC is a promising antibacterial agent to control citrus canker disease.
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Affiliation(s)
- Libin Jiang
- College of Chemistry, Fuzhou University, Fuzhou, China
| | - Yurong Liu
- College of Chemistry, Fuzhou University, Fuzhou, China
| | - Xianyuan Xu
- State Key Laboratory of Ecological Pest Control for Fujian and Taiwan Crops, Fujian University Key Laboratory for Plant-Microbe Interaction, College of Plant Protection, Fujian Agriculture and Forestry University, Fuzhou, China
| | - Dan Su
- College of Chemistry, Fuzhou University, Fuzhou, China
| | - Huasong Zou
- State Key Laboratory of Ecological Pest Control for Fujian and Taiwan Crops, Fujian University Key Laboratory for Plant-Microbe Interaction, College of Plant Protection, Fujian Agriculture and Forestry University, Fuzhou, China
| | - Jianyong Liu
- College of Chemistry, Fuzhou University, Fuzhou, China
| | - Cai Yuan
- College of Biological Science and Engineering, Fuzhou University, Fuzhou, China
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Ndemueda A, Pereira I, Faustino MAF, Cunha Â. Photodynamic inactivation of the phytopathogenic bacterium Xanthomonas citri subsp. citri. Lett Appl Microbiol 2020; 71:420-427. [PMID: 32628776 DOI: 10.1111/lam.13350] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2020] [Revised: 06/13/2020] [Accepted: 06/29/2020] [Indexed: 12/12/2022]
Abstract
The present work intended to evaluate the applicability of photodynamic inactivation (PDI) of Xanthomonas citri subsp. citri with toluidine blue O (TBO), a commercial photosensitizer, as a strategy to control citrus canker. Assays were conducted with cell suspensions and biofilms, constructed either on polypropylene microtubes (in vitro assays) or on the surface of orange leaves (ex vivo assays), in the presence of TBO and under irradiation with artificial white light or natural sunlight. PDI assays using TBO alone caused a maximum 5·8 log10 reduction of X. citri viable cells in suspensions, and a much smaller inactivation (1·5 log10) in biofilms. However, concomitant use of KI potentiated the TBO photosensitization. Biofilms were inactivated down to the detection limit (>6 log10 reduction) with 5·0 µmol l-1 TBO + 10 mmol l-1 KI (in vitro) or 5·0 µmol l-1 TBO + 100 mmol l-1 KI (ex vivo) after artificial white light irradiation. Under natural sunlight, a reduction down to the detection limit of the Miles-Misra method was achieved with 50 µmol l-1 TBO and 100 mmol l-1 KI. PDI has potential to be applied in the control of citrus canker in field conditions although further studies are needed to show that there are no risks to plant physiology or fruit quality. SIGNIFICANCE AND IMPACT OF THE STUDY: Xanthomonas citri subsp. citri is a major cause of disease in citrus orchards. Because of the low efficacy and high environmental toxicity of copper-based treatments, there is growing interest on more sustainable phytosanitary approaches. Photodynamic inactivation (PDI) is being successfully used to control infectious agents and literature reports indicate that it is effective against some fungi and bacteria attacking fruit crops. The results of the present work open the perspective of using a low-cost photosensitizer and sunlight, as energy source, to control of the causative agent of citrus canker.
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Affiliation(s)
- A Ndemueda
- CESAM and Department of Biology, University of Aveiro, Aveiro, Portugal
| | - I Pereira
- CESAM and Department of Biology, University of Aveiro, Aveiro, Portugal
| | - M A F Faustino
- LAQV-REQUIMTE and Department of Chemistry, University of Aveiro, Aveiro, Portugal
| | - Â Cunha
- CESAM and Department of Biology, University of Aveiro, Aveiro, Portugal
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Hilario E, De Keyser S, Fan L. Structural and biochemical characterization of a glutathione transferase from the citrus canker pathogen Xanthomonas. Acta Crystallogr D Struct Biol 2020; 76:778-789. [PMID: 32744260 PMCID: PMC7397488 DOI: 10.1107/s2059798320009274] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2020] [Accepted: 07/07/2020] [Indexed: 11/10/2022] Open
Abstract
The genus Xanthomonas comprises several cosmopolitan plant-pathogenic bacteria that affect more than 400 plant species, most of which are of economic interest. Citrus canker is a bacterial disease that affects citrus species, reducing fruit yield and quality, and is caused by the bacterium Xanthomonas citri subsp. citri (Xac). The Xac3819 gene, which has previously been reported to be important for citrus canker infection, encodes an uncharacterized glutathione S-transferase (GST) of 207 amino-acid residues in length (XacGST). Bacterial GSTs are implicated in a variety of metabolic processes such as protection against chemical and oxidative stresses. XacGST shares high sequence identity (45%) with the GstB dehalogenase from Escherichia coli O6:H1 strain CFT073 (EcGstB). Here, XacGST is reported to be able to conjugate glutathione (GSH) with bromoacetate with a Km of 6.67 ± 0.77 mM, a kcat of 42.69 ± 0.32 s-1 and a kcat/Km of 6.40 ± 0.72 mM-1 s-1 under a saturated GSH concentration (3.6 mM). These values are comparable to those previously reported for EcGstB. In addition, crystal structures of XacGST were determined in the apo form (PDB entry 6nxv) and in a GSH-bound complex (PDB entry 6nv6). XacGST has a canonical GST-like fold with a conserved serine residue (Ser12) at the GSH-binding site near the N-terminus, indicating XacGST to be a serine-type GST that probably belongs to the theta-class GSTs. GSH binding stabilizes a loop of about 20 residues containing a helix that is disordered in the apo XacGST structure.
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Affiliation(s)
- Eduardo Hilario
- Department of Biochemistry, University of California-Riverside, Riverside, California, USA
| | - Sawyer De Keyser
- Department of Biochemistry, University of California-Riverside, Riverside, California, USA
| | - Li Fan
- Department of Biochemistry, University of California-Riverside, Riverside, California, USA
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Julião MHM, Silva SR, Ferro JA, Varani AM. A Genomic and Transcriptomic Overview of MATE, ABC, and MFS Transporters in Citrus sinensis Interaction with Xanthomonas citri subsp. citri. Plants (Basel) 2020; 9:E794. [PMID: 32630416 PMCID: PMC7356318 DOI: 10.3390/plants9060794] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/01/2020] [Revised: 06/08/2020] [Accepted: 06/18/2020] [Indexed: 02/07/2023]
Abstract
The multi-antimicrobial extrusion (MATE), ATP-binding cassette (ABC), and major facilitator superfamily (MFS) are the main plant transporters families, playing an essential role in the membrane-trafficking network and plant-defense mechanism. The citrus canker type A (CC), is a devastating disease caused by Xanthomonas citri subsp. citri (Xac), affecting all citrus species. In this work, we performed an in silico analysis of genes and transcripts from MATE, ABC, and MFS families to infer the role of membrane transporters in Citrus-Xac interaction. Using as reference, the available Citrus sinensis genome and the citrus reference transcriptome from CitrusKB database, 67 MATE, 91 MFS, and 143 ABC genes and 82 MATE, 139 MFS, and 226 ABC transcripts were identified and classified into subfamilies. Duplications, alternative-splicing, and potentially non-transcribed transporters' genes were revealed. Interestingly, MATE I and ABC G subfamilies appear differently regulated during Xac infection. Furthermore, Citrus spp. showing distinct levels of CC susceptibility exhibited different sets of transporters transcripts, supporting dissimilar molecular patterns of membrane transporters in Citrus-Xac interaction. According to our findings, 4 MATE, 10 ABC, and 3 MFS are potentially related to plant-defense mechanisms. Overall, this work provides an extensive analysis of MATE, ABC, and MFS transporters' in Citrus-Xac interaction, bringing new insights on membrane transporters in plant-pathogen interactions.
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Affiliation(s)
| | | | | | - Alessandro M. Varani
- Department of Technology, School of Agricultural and Veterinary Sciences, São Paulo State University, Jaboticabal 14884-900, Brazil; (M.H.M.J.); (S.R.S.); (J.A.F.)
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Lyu S, Yu Y, Xu S, Cai W, Chen G, Chen J, Pan D, She W. Identification of Appropriate Reference Genes for Normalizing miRNA Expression in Citrus Infected by Xanthomonas citri subsp. citri. Genes (Basel) 2019; 11:E17. [PMID: 31877985 DOI: 10.3390/genes11010017] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2019] [Revised: 12/13/2019] [Accepted: 12/16/2019] [Indexed: 01/01/2023] Open
Abstract
MicroRNAs (miRNAs) are short noncoding RNA molecules that regulate gene expression at the posttranscriptional level. Reverse transcription-quantitative PCR (RT-qPCR) is one of the most common methods used for quantification of miRNA expression, and the levels of expression are normalized by comparing with reference genes. Thus, the selection of reference genes is critically important for accurate quantification. The present study was intended to identify appropriate miRNA reference genes for normalizing the level of miRNA expression in Citrus sinensis L. Osbeck and Citrus reticulata Blanco infected by Xanthomonas citri subsp. citri, which caused citrus canker disease. Five algorithms (Delta Ct, geNorm, NormFinder, BestKeeper and RefFinder) were used for screening reference genes, and two quantification approaches, poly(A) extension RT-qPCR and stem-loop RT-qPCR, were used to determine the most appropriate method for detecting expression patterns of miRNA. An overall comprehensive ranking output derived from the multi-algorithms showed that poly(A)-tailed miR162-3p/miR472 were the best reference gene combination for miRNA RT-qPCR normalization in citrus canker research. Candidate reference gene expression profiles determined by poly(A) RT-qPCR were more consistent in the two citrus species. To the best of our knowledge, this is the first systematic comparison of two miRNA quantification methods for evaluating reference genes. These results highlight the importance of rigorously assessing candidate reference genes and clarify some contradictory results in miRNA research on citrus.
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Maxwell TJ, Rajasekaran P, Das S, Campos MGN, Young M, Mendis HC, Ozcan A, Gerberich KM, Myers ME, Graham JH, Johnson EG, Santra S. Control of Citrus Canker in Greenhouse and Field with a Zinc, Urea, and Peroxide Ternary Solution. J Agric Food Chem 2019; 67:12393-12401. [PMID: 31596571 DOI: 10.1021/acs.jafc.9b05108] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/17/2023]
Abstract
Accumulation of toxic copper in soil and development of copper-resistant pests are emerging challenges currently faced by the agricultural community worldwide. As an alternative, we have developed a ternary zinc chelate solution (TSOL) pesticide where zinc ions are the primary active ingredient. The material is composed of zinc, urea, and hydrogen peroxide. Urea was chosen as it is widely used as a plant fertilizer and can also bind to both zinc and hydrogen peroxide. No phytotoxicity was observed with TSOL on Meyer lemon (Citrus × meyeri) seedlings at a field spray rate of 800 μg/mL Zn metal concentration. Antimicrobial studies showed that TSOL exhibited improved killing efficacy against Escherichia coli and Xanthomonas alfalfae compared to Zn ions alone. Citrus canker field trials in a grapefruit (Chrysopelea paradisi) grove over three years showed that TSOL provided comparable disease protection to copper products at an equivalent or lower metal content.
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Affiliation(s)
| | | | | | | | | | | | | | - Kayla M Gerberich
- Citrus Research and Education Center , University of Florida , 700 Experiment Station Road , Lake Alfred , Florida 33850 , United States
| | - Monty E Myers
- Indian River Research and Education Center , University of Florida , 2199 South Rock Road , Fort Pierce , Florida 34945 , United States
| | - James H Graham
- Citrus Research and Education Center , University of Florida , 700 Experiment Station Road , Lake Alfred , Florida 33850 , United States
| | - Evan G Johnson
- Citrus Research and Education Center , University of Florida , 700 Experiment Station Road , Lake Alfred , Florida 33850 , United States
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38
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Islam MN, Ali MS, Choi SJ, Hyun JW, Baek KH. Biocontrol of Citrus Canker Disease Caused by Xanthomonas citri subsp. citri Using an Endophytic Bacillus thuringiensis. Plant Pathol J 2019; 35:486-497. [PMID: 31632223 PMCID: PMC6788417 DOI: 10.5423/ppj.oa.03.2019.0060] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/20/2019] [Revised: 07/05/2019] [Accepted: 08/12/2019] [Indexed: 05/14/2023]
Abstract
Citrus canker is a devastating disease of citrus caused by Xanthomonas citri subsp. citri (Xcc). A total of 134 endophytic bacteria were isolated from various gymnospermic and angiospermic plants. They were screened for their antagonistic activities against three wild-type and six streptomycin-resistant Xcc strains. TbL-22 and TbL-26, both later identified as Bacillus thuringiensis, inhibited all the wild and resistant Xcc strains. TbL-22 exerted the highest antagonistic activity against XccW3 and XccM6 with inhibition zones of 20.64 ± 0.69 and 19.91 ± 0.87 mm, respectively. Similarly ethyl acetate extract of TbL-22 showed highest inhibition zones 15.31 ± 2.08 and 19.37 ± 3.17 mm against XccW3 and XccM6, respectively. TbL-22 reduced canker incidence on infected leaves by 64.05% relative to positive controls. Scanning electron microscopy revealed that the cell membranes of Xcc treated with ethyl acetate extract of TbL-22 were ruptured, lysed, and swollen. B. thuringiensis TbL-22 can effectively and sustainably controls streptomycin-resistant citrus canker.
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Affiliation(s)
- Md. Nurul Islam
- Department of Biotechnology, Yeungnam University, Gyeongsan 38541,
Korea
| | - Md. Sarafat Ali
- Department of Biotechnology, Yeungnam University, Gyeongsan 38541,
Korea
| | - Seong-Jin Choi
- Department of Biotechnology, Catholic University of Daegu, Gyeongsan 38430,
Korea
| | - Jae-Wook Hyun
- Citrus Research Station, National Institute of Horticultural and Herbal Science, Rural Development Administration, Seogwipo 63607,
Korea
| | - Kwang-Hyun Baek
- Department of Biotechnology, Yeungnam University, Gyeongsan 38541,
Korea
- Corresponding author.: Phone) +82-53-810-3029, FAX) +82-53-810-4769, E-mail)
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Hamido SA, Ebel RC, Morgan KT. Interaction of Huanglongbing and Foliar Applications of Copper on Water Relations of Citrus sinensis cv. Valencia. Plants (Basel) 2019; 8:plants8090298. [PMID: 31443580 DOI: 10.21273/hortsci13674-18] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/10/2019] [Revised: 08/16/2019] [Accepted: 08/19/2019] [Indexed: 05/27/2023]
Abstract
The following study was conducted to determine the impact of frequent foliar Cu applications on water relations of Huanglongbing (HLB)-affected Citrus sinensis cv. 'Valencia'. HLB in Florida is putatively caused by Candidatus Liberibacter asiaticus that is vectored by the Asian citrus psyllid. The experiment was conducted in a psyllid-free greenhouse with trees grown in Immokalee fine sand soil with the trees well-maintained to promote health. Cu was applied to the foliage at 0×, 0.5×, 1×, and 2× the commercially recommended rates, which were 0, 46, 92, and 184 mM, respectively, with applications made 3× in both 2016 and 2017. Previous studies indicate that HLB causes roots to decline before the canopy develops symptoms, which increases the ratio between the evaporative surface area of the canopy to the uptake surface area of roots and increases the hydraulic strain within the tree. In the current study, overall growth was suppressed substantially by HLB and Cu treatments but the ratio between evaporative surface area (leaf surface area) and the uptake surface area of roots (feeder root surface area) was not affected by either treatment. Stem water potential (Ψxylem), which was used as a measure of plant water deficits and the hydraulic strain within the tree, was significantly 13% lower for HLB-affected trees than the non-HLB controls but were not affected by Cu treatments. All Ψxylem measurements were in a range typical of well-watered trees conditions. Stomatal conductance (ks) and root and soil resistances (Rr+s) were not affected by HLB and Cu. The results of this experiment suggest that tree leaf area and feeder roots are reduced when the trees are affected by HLB or are treated with foliar Cu applications such that plant water deficits are not significantly different over that of the controls.
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Affiliation(s)
- Said A Hamido
- Southwest Florida Research and Education Center, University of Florida, 2685 SR 29 N, Immokalee, FL 34142, USA.
| | - Robert C Ebel
- Southwest Florida Research and Education Center, University of Florida, 2685 SR 29 N, Immokalee, FL 34142, USA
| | - Kelly T Morgan
- Southwest Florida Research and Education Center, University of Florida, 2685 SR 29 N, Immokalee, FL 34142, USA
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Hamido SA, Ebel RC, Morgan KT. Interaction of Huanglongbing and Foliar Applications of Copper on Water Relations of Citrus sinensis cv. Valencia. Plants (Basel) 2019; 8:E298. [PMID: 31443580 PMCID: PMC6784184 DOI: 10.3390/plants8090298] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/10/2019] [Revised: 08/16/2019] [Accepted: 08/19/2019] [Indexed: 12/05/2022]
Abstract
The following study was conducted to determine the impact of frequent foliar Cu applications on water relations of Huanglongbing (HLB)-affected Citrus sinensis cv. 'Valencia'. HLB in Florida is putatively caused by Candidatus Liberibacter asiaticus that is vectored by the Asian citrus psyllid. The experiment was conducted in a psyllid-free greenhouse with trees grown in Immokalee fine sand soil with the trees well-maintained to promote health. Cu was applied to the foliage at 0×, 0.5×, 1×, and 2× the commercially recommended rates, which were 0, 46, 92, and 184 mM, respectively, with applications made 3× in both 2016 and 2017. Previous studies indicate that HLB causes roots to decline before the canopy develops symptoms, which increases the ratio between the evaporative surface area of the canopy to the uptake surface area of roots and increases the hydraulic strain within the tree. In the current study, overall growth was suppressed substantially by HLB and Cu treatments but the ratio between evaporative surface area (leaf surface area) and the uptake surface area of roots (feeder root surface area) was not affected by either treatment. Stem water potential (Ψxylem), which was used as a measure of plant water deficits and the hydraulic strain within the tree, was significantly 13% lower for HLB-affected trees than the non-HLB controls but were not affected by Cu treatments. All Ψxylem measurements were in a range typical of well-watered trees conditions. Stomatal conductance (ks) and root and soil resistances (Rr+s) were not affected by HLB and Cu. The results of this experiment suggest that tree leaf area and feeder roots are reduced when the trees are affected by HLB or are treated with foliar Cu applications such that plant water deficits are not significantly different over that of the controls.
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Affiliation(s)
- Said A Hamido
- Southwest Florida Research and Education Center, University of Florida, 2685 SR 29 N, Immokalee, FL 34142, USA.
| | - Robert C Ebel
- Southwest Florida Research and Education Center, University of Florida, 2685 SR 29 N, Immokalee, FL 34142, USA
| | - Kelly T Morgan
- Southwest Florida Research and Education Center, University of Florida, 2685 SR 29 N, Immokalee, FL 34142, USA
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Shimo HM, Terassi C, Lima Silva CC, Zanella JDL, Mercaldi GF, Rocco SA, Benedetti CE. Role of the Citrus sinensis RNA deadenylase CsCAF1 in citrus canker resistance. Mol Plant Pathol 2019; 20:1105-1118. [PMID: 31115151 PMCID: PMC6640180 DOI: 10.1111/mpp.12815] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Poly(A) tail shortening is a critical step in messenger RNA (mRNA) decay and control of gene expression. The carbon catabolite repressor 4 (CCR4)-associated factor 1 (CAF1) component of the CCR4-NOT deadenylase complex plays an essential role in mRNA deadenylation in most eukaryotes. However, while CAF1 has been extensively investigated in yeast and animals, its role in plants remains largely unknown. Here, we show that the Citrus sinensis CAF1 (CsCAF1) is a magnesium-dependent deadenylase implicated in resistance against the citrus canker bacteria Xanthomonas citri. CsCAF1 interacted with proteins of the CCR4-NOT complex, including CsVIP2, a NOT2 homologue, translin-associated factor X (CsTRAX) and the poly(A)-binding proteins CsPABPN and CsPABPC. CsCAF1 also interacted with PthA4, the main X. citri effector required for citrus canker elicitation. We also present evidence suggesting that PthA4 inhibits CsCAF1 deadenylase activity in vitro and stabilizes the mRNA encoded by the citrus canker susceptibility gene CsLOB1, which is transcriptionally activated by PthA4 during canker formation. Moreover, we show that an inhibitor of CsCAF1 deadenylase activity significantly enhanced canker development, despite causing a reduction in PthA4-dependent CsLOB1 transcription. These results thus link CsCAF1 with canker development and PthA4-dependent transcription in citrus plants.
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Affiliation(s)
- Hugo Massayoshi Shimo
- Brazilian Biosciences National Laboratory (LNBio)Brazilian Center for Research in Energy and Materials (CNPEM)CEP 13083‐100CampinasSPBrazil
| | - Carolina Terassi
- Brazilian Biosciences National Laboratory (LNBio)Brazilian Center for Research in Energy and Materials (CNPEM)CEP 13083‐100CampinasSPBrazil
| | - Caio Cesar Lima Silva
- Brazilian Biosciences National Laboratory (LNBio)Brazilian Center for Research in Energy and Materials (CNPEM)CEP 13083‐100CampinasSPBrazil
| | - Jackeline de Lima Zanella
- Brazilian Biosciences National Laboratory (LNBio)Brazilian Center for Research in Energy and Materials (CNPEM)CEP 13083‐100CampinasSPBrazil
| | - Gustavo Fernando Mercaldi
- Brazilian Biosciences National Laboratory (LNBio)Brazilian Center for Research in Energy and Materials (CNPEM)CEP 13083‐100CampinasSPBrazil
| | - Silvana Aparecida Rocco
- Brazilian Biosciences National Laboratory (LNBio)Brazilian Center for Research in Energy and Materials (CNPEM)CEP 13083‐100CampinasSPBrazil
| | - Celso Eduardo Benedetti
- Brazilian Biosciences National Laboratory (LNBio)Brazilian Center for Research in Energy and Materials (CNPEM)CEP 13083‐100CampinasSPBrazil
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Shuai J, Guan F, He B, Hu J, Li Y, He D, Hu J. Self-Assembled Nanoparticles of Symmetrical Cationic Peptide Against Citrus Pathogenic Bacteria. J Agric Food Chem 2019; 67:5720-5727. [PMID: 31046262 DOI: 10.1021/acs.jafc.9b00820] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
The increasing drug resistance of phytopathogenic bacteria to conventional bactericides has driven the necessity for exploring new alternatives with a lower tendency to develop bacterial resistance. Here, we report a novel cationic symmetrical peptide P5VP5 (Ac- R+ LI R+ K+ V K+ R+ IL R+ -NH2 that enables self-assembly to form nanoparticles with excellent thermal stability. An in vitro assay showed that P5VP5 nanoparticles exhibited excellent antibacterial activity against Xanthomonas axonopodis pv citri with a MIC value of 20 μM. Meanwhile, under an in planta condition, treatment with peptide nanoparticles demonstrated the highest ability to reduce the development of citrus canker lesions in leaves. Moreover, the nanoparticles could destroy the biofilm formation, damage the cell membranes, and affect the cell membrane permeability, ultimately leading to the death of bacteria. Taken together, these nanoparticles are a promising antibacterial agent that can be used to control citrus canker and other plant diseases caused by bacteria.
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Affiliation(s)
- Jianbo Shuai
- School of Chemistry and Chemical Engineering , South China University of Technology , Guangzhou 510640 , China
| | - Fuyi Guan
- School of Chemistry and Chemical Engineering , South China University of Technology , Guangzhou 510640 , China
| | - Bi He
- School of Chemistry and Chemical Engineering , South China University of Technology , Guangzhou 510640 , China
| | - Jianqing Hu
- School of Chemistry and Chemical Engineering , South China University of Technology , Guangzhou 510640 , China
| | - Yan Li
- School of Chemistry and Chemical Engineering , South China University of Technology , Guangzhou 510640 , China
| | - Daohang He
- School of Chemistry and Chemical Engineering , South China University of Technology , Guangzhou 510640 , China
| | - Jianfeng Hu
- School of Chemistry and Chemical Engineering , South China University of Technology , Guangzhou 510640 , China
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Balogh B, Nga NTT, Jones JB. Corrigendum: Relative Level of Bacteriophage Multiplication in vitro or in Phyllosphere May Not Predict in planta Efficacy for Controlling Bacterial Leaf Spot on Tomato Caused by Xanthomonas perforans. Front Microbiol 2018; 9:2647. [PMID: 30402052 PMCID: PMC6216461 DOI: 10.3389/fmicb.2018.02647] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2018] [Accepted: 10/17/2018] [Indexed: 11/13/2022] Open
Abstract
[This corrects the article DOI: 10.3389/fmicb.2018.02176.].
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Affiliation(s)
- Botond Balogh
- Plant Pathology Department, University of Florida, Gainesville, FL, United States
| | | | - Jeffrey B Jones
- Plant Pathology Department, University of Florida, Gainesville, FL, United States
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Alferez FM, Gerberich KM, Li JL, Zhang Y, Graham JH, Mou Z. Exogenous Nicotinamide Adenine Dinucleotide Induces Resistance to Citrus Canker in Citrus. Front Plant Sci 2018; 9:1472. [PMID: 30356715 PMCID: PMC6189366 DOI: 10.3389/fpls.2018.01472] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/28/2018] [Accepted: 09/20/2018] [Indexed: 05/11/2023]
Abstract
Nicotinamide adenine dinucleotide (NAD) is a universal electron carrier that participates in important intracellular metabolic reactions and signaling events. Interestingly, emerging evidence in animals indicates that cellular NAD can be actively or passively released into the extracellular space, where it is processed or perceived by ectoenzymes or cell-surface receptors. We have recently shown in Arabidopsis thaliana that exogenous NAD induces defense responses, that pathogen infection leads to release of NAD into the extracellular space at concentrations sufficient for defense activation, and that depletion of extracellular NAD (eNAD) by transgenic expression of the human NAD-hydrolyzing ectoenzyme CD38 inhibits plant immunity. We therefore hypothesize that, during plant-microbe interactions, NAD is released from dead or dying cells into the extracellular space where it interacts with adjacent naïve cells' surface receptors, which in turn activate downstream immune signaling. However, it is currently unknown whether eNAD signaling is unique to Arabidopsis or the Brassicaceae family. In this study, we treated citrus plants with exogenous NAD+ and tested NAD+-induced transcriptional changes and disease resistance. Our results show that NAD+ induces profound transcriptome changes and strong resistance to citrus canker, a serious citrus disease caused by the bacterial pathogen Xanthomonas citri subsp. citri (Xcc). Furthermore, NAD+-induced resistance persists in new flushes emerging after removal of the tissues previously treated with NAD+. Finally, NAD+ treatment primes citrus tissues, resulting in a faster and stronger induction of multiple salicylic acid pathway genes upon subsequent Xcc infection. Taken together, these results indicate that exogenous NAD+ is able to induce immune responses in citrus and suggest that eNAD may also be an elicitor in this woody plant species.
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Affiliation(s)
- Fernando M. Alferez
- Citrus Research and Education Center, University of Florida, Lake Alfred, FL, United States
- Southwest Florida Research and Education Center, University of Florida, Immokalee, FL, United States
| | - Kayla M. Gerberich
- Citrus Research and Education Center, University of Florida, Lake Alfred, FL, United States
| | - Jian-Liang Li
- National Institute of Environmental Health Sciences, National Institutes of Health, Durham, NC, United States
| | - Yanping Zhang
- Interdisciplinary Center for Biotechnology Research, University of Florida, Gainesville, FL, United States
| | - James H. Graham
- Citrus Research and Education Center, University of Florida, Lake Alfred, FL, United States
| | - Zhonglin Mou
- Department of Microbiology and Cell Science, University of Florida, Gainesville, FL, United States
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Nazaré AC, Polaquini CR, Cavalca LB, Anselmo DB, Saiki MDFC, Monteiro DA, Zielinska A, Rahal P, Gomes E, Scheffers DJ, Ferreira H, Regasini LO. Design of Antibacterial Agents: Alkyl Dihydroxybenzoates against Xanthomonas citri subsp. citri. Int J Mol Sci 2018; 19:E3050. [PMID: 30301234 PMCID: PMC6213047 DOI: 10.3390/ijms19103050] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2018] [Revised: 09/28/2018] [Accepted: 10/01/2018] [Indexed: 01/27/2023] Open
Abstract
Xanthomonas citri subsp. citri (Xcc) causes citrus canker, affecting sweet orange-producing areas around the world. The current chemical treatment available for this disease is based on cupric compounds. For this reason, the objective of this study was to design antibacterial agents. In order to do this, we analyzed the anti-Xcc activity of 36 alkyl dihydroxybenzoates and we found 14 active compounds. Among them, three esters with the lowest minimum inhibitory concentration values were selected; compounds 4 (52 μM), 16 (80 μM) and 28 (88 μM). Our study demonstrated that alkyl dihydroxybenzoates cause a delay in the exponential phase. The permeability capacity of alkyl dihydroxybenzoates in a quarter of MIC was compared to nisin (positive control). Compound 28 was the most effective (93.8), compared to compound 16 (41.3) and compound 4 (13.9) by percentage values. Finally, all three compounds showed inhibition of FtsZ GTPase activity, and promoted changes in protofilaments, leading to depolymerization, which prevents bacterial cell division. In conclusion, heptyl dihydroxybenzoates (compounds 4, 16 and 28) are promising anti-Xcc agents which may serve as an alternative for the control of citrus canker.
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Affiliation(s)
- Ana Carolina Nazaré
- Department of Chemistry and Environmental Sciences, Institute of Biosciences, Humanities and Exact Sciences, São Paulo State University, São José do Rio Preto, SP 15054-000, Brazil.
| | - Carlos Roberto Polaquini
- Department of Chemistry and Environmental Sciences, Institute of Biosciences, Humanities and Exact Sciences, São Paulo State University, São José do Rio Preto, SP 15054-000, Brazil.
| | - Lúcia Bonci Cavalca
- Department of Biochemistry and Microbiology, Biosciences Institute, São Paulo State University, Rio Claro, SP 13506-900, Brazil.
- Department of Molecular Microbiology, Groningen Biomolecular Sciences and Biotechnology Institute, University of Groningen, 9747 AG Groningen, The Netherlands.
| | - Daiane Bertholin Anselmo
- Department of Chemistry and Environmental Sciences, Institute of Biosciences, Humanities and Exact Sciences, São Paulo State University, São José do Rio Preto, SP 15054-000, Brazil.
| | - Marilia de Freitas Calmon Saiki
- Department of Biology, Institute of Biosciences, Humanities and Exact Sciences, São Paulo State University, IBILCE, São José do Rio Preto, SP 15054-000, Brazil.
| | - Diego Alves Monteiro
- Department of Biology, Institute of Biosciences, Humanities and Exact Sciences, São Paulo State University, IBILCE, São José do Rio Preto, SP 15054-000, Brazil.
| | - Aleksandra Zielinska
- Department of Molecular Microbiology, Groningen Biomolecular Sciences and Biotechnology Institute, University of Groningen, 9747 AG Groningen, The Netherlands.
| | - Paula Rahal
- Department of Biology, Institute of Biosciences, Humanities and Exact Sciences, São Paulo State University, IBILCE, São José do Rio Preto, SP 15054-000, Brazil.
| | - Eleni Gomes
- Department of Biology, Institute of Biosciences, Humanities and Exact Sciences, São Paulo State University, IBILCE, São José do Rio Preto, SP 15054-000, Brazil.
| | - Dirk-Jan Scheffers
- Department of Molecular Microbiology, Groningen Biomolecular Sciences and Biotechnology Institute, University of Groningen, 9747 AG Groningen, The Netherlands.
| | - Henrique Ferreira
- Department of Biochemistry and Microbiology, Biosciences Institute, São Paulo State University, Rio Claro, SP 13506-900, Brazil.
| | - Luis Octavio Regasini
- Department of Chemistry and Environmental Sciences, Institute of Biosciences, Humanities and Exact Sciences, São Paulo State University, São José do Rio Preto, SP 15054-000, Brazil.
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Balogh B, Nga NTT, Jones JB. Relative Level of Bacteriophage Multiplication in vitro or in Phyllosphere May Not Predict in planta Efficacy for Controlling Bacterial Leaf Spot on Tomato Caused by Xanthomonas perforans. Front Microbiol 2018; 9:2176. [PMID: 30283415 PMCID: PMC6157332 DOI: 10.3389/fmicb.2018.02176] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2018] [Accepted: 08/24/2018] [Indexed: 11/13/2022] Open
Abstract
Following analysis of eight phages under in vitro, growth chamber and greenhouse conditions with the bacterial spot of tomato pathogen Xanthomonas perforans, there was no correlation between disease control efficacy and in vitro phage multiplication, in vitro bacterial suppression, or in vivo phage multiplication in the presence of the host, but there was a low correlation between phage persistence on the leaf surface and disease control. Two of the 8 virulent phages (ΦXv3-21 and ΦXp06-02) were selected for in depth analysis with two X. perforans (Xp06-2-1 and Xp17-12) strains. In in vitro experiments, phage ΦXv3-21 was equally effective in infecting the two bacterial strains based on efficiency of plating (EOP). Phage ΦXp06-02, on the other hand, had a high EOP on strain Xp06-2-1 but a lower EOP on strain Xp17-12. In several growth chamber experiments, ΦXv3-21 was less effective than phage ΦXp06-02 in reducing disease caused by strain Xp06-2-1, but provided little or no disease control against strain Xp17-12. Interestingly, ΦXp06-02 could multiply to significantly higher levels on the tomato leaf surface than phage ΦXv3-21. The leaf surface appears to be important in terms of the ability of certain bacteriophages to multiply in the presence of the bacterial host. ΦXv3-21, when applied to grapefruit leaves in combination with a bacterial host, was unable to multiply to high levels, whereas on tomato leaflets the phage multiplied exponentially. One plausible explanation is that the leaf surface may be an important factor for attachment of certain phages to their bacterial host.
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Affiliation(s)
- Botond Balogh
- Plant Pathology Department, University of Florida, Gainesville, FL, United States
| | | | - Jeffrey B. Jones
- Plant Pathology Department, University of Florida, Gainesville, FL, United States
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Young M, Ozcan A, Myers ME, Johnson EG, Graham JH, Santra S. Multimodal Generally Recognized as Safe ZnO/Nanocopper Composite: A Novel Antimicrobial Material for the Management of Citrus Phytopathogens. J Agric Food Chem 2018; 66:6604-6608. [PMID: 28832140 DOI: 10.1021/acs.jafc.7b02526] [Citation(s) in RCA: 30] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
Copper (Cu) bactericides/fungicides are used extensively for crop protection in agriculture. Concerns for Cu accumulation in soil, Cu leaching into the surrounding ecosystem, and development of Cu resistance in phytopathogenic bacteria are evident. While there is no suitable alternative to Cu available to date for agricultural uses, it is possible to reduce Cu per application by supplementing with Zn and improving Cu bioavailability using nanotechnology. We have prepared a non-phytotoxic composite material consisting of generally recognized as safe ZnO 800 particles and nanocopper-loaded silica gel (ZnO-nCuSi). The morphology of the ZnO-nCuSi material was characterized using scanning electron microscopy, showing ZnO particles dispersed in the silica gel matrix. ZnO-nCuSi demonstrated strong in vitro antimicrobial properties against several model plant bacterial species. Two consecutive year field efficacy results showed that agri-grade ZnO-nCuSi was effective in controlling citrus canker disease at less than half the metallic rate of the commercial cuprous oxide/zinc oxide pesticide.
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Affiliation(s)
| | | | - Monty E Myers
- Indian River Research and Education Center , University of Florida , 2199 South Rock Road , Fort Pierce , Florida 34945 , United States
| | - Evan G Johnson
- Citrus Research and Education Center , University of Florida , 700 Experiment Road , Lake Alfred , Florida 33850 , United States
| | - James H Graham
- Citrus Research and Education Center , University of Florida , 700 Experiment Road , Lake Alfred , Florida 33850 , United States
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Duan S, Jia H, Pang Z, Teper D, White F, Jones J, Zhou C, Wang N. Functional characterization of the citrus canker susceptibility gene CsLOB1. Mol Plant Pathol 2018; 19:1908-1916. [PMID: 29461671 PMCID: PMC6638005 DOI: 10.1111/mpp.12667] [Citation(s) in RCA: 31] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/08/2017] [Revised: 01/29/2018] [Accepted: 02/16/2018] [Indexed: 05/08/2023]
Abstract
Xanthomonas citri ssp. citri (Xcc) is an important plant-pathogenic bacterium that causes citrus canker disease worldwide. PthA, a transcriptional activator-like (TAL) effector, directs the expression of the canker susceptibility gene CsLOB1. Here, we report our recent progress in the functional characterization of CsLOB1. Subcellular localization analysis of CsLOB1 protein in citrus protoplast revealed that CsLOB1 is primarily localized in the nucleus. We showed that CsLOB1 expression driven by dexamethasone (DEX) in CsLOB1-GR transgenic plants is associated with pustule formation following treatment with DEX. Pustule formation was not observed in DEX-treated wild-type plants and in non-treated CsLOB1-GR transgenic plants. Water soaking is typically associated with symptoms of citrus canker. Weaker water soaking was observed with pustule formation in CsLOB1-GR transgenic plants following DEX treatment. When CsLOB1-GR-transgenic Duncan grapefruit leaves were inoculated with Xcc306ΔpthA4 and treated with DEX, typical canker symptoms, including hypertrophy, hyperplasia and water soaking symptoms, were observed on DEX-treated transgenic plant leaves, but not on mock-treated plants. Twelve citrus genes that are induced by PthA4 are also stimulated by the DEX-induced expression of CsLOB1. As CsLOB1 acts as a transcriptional factor, we identified putative targets of CsLOB1 via bioinformatic and electrophoretic mobility shift assays. Cs2g20600, which encodes a zinc finger C3HC4-type RING finger protein, has been identified to be a direct target of CsLOB1. This study advances our understanding of the function of CsLOB1 and the molecular mechanism of how Xcc causes canker symptoms via CsLOB1.
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Affiliation(s)
- Shuo Duan
- Citrus Research InstituteSouthwest University, Chongqing400712, China
- Department of Microbiology and Cell Science, Citrus Research and Education Center, Institute of Food and Agricultural Sciences (IFAS)University of FloridaLake AlfredFL 33850USA
| | - Hongge Jia
- Department of Microbiology and Cell Science, Citrus Research and Education Center, Institute of Food and Agricultural Sciences (IFAS)University of FloridaLake AlfredFL 33850USA
| | - Zhiqian Pang
- Department of Microbiology and Cell Science, Citrus Research and Education Center, Institute of Food and Agricultural Sciences (IFAS)University of FloridaLake AlfredFL 33850USA
| | - Doron Teper
- Department of Microbiology and Cell Science, Citrus Research and Education Center, Institute of Food and Agricultural Sciences (IFAS)University of FloridaLake AlfredFL 33850USA
| | - Frank White
- Department of Plant PathologyUniversity of FloridaGainesvilleFL 32611USA
| | - Jeffrey Jones
- Department of Plant PathologyUniversity of FloridaGainesvilleFL 32611USA
| | - Changyong Zhou
- Citrus Research InstituteSouthwest University, Chongqing400712, China
| | - Nian Wang
- Department of Microbiology and Cell Science, Citrus Research and Education Center, Institute of Food and Agricultural Sciences (IFAS)University of FloridaLake AlfredFL 33850USA
- China‐USA Citrus Huanglongbing Joint Laboratory (A joint laboratory of The University of Florida's Institute of Food and Agricultural Sciences and Gannan Normal University)National Navel Orange Engineering Research Center, Gannan Normal UniversityGanzhouJiangxiChina
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Artier J, da Silva Zandonadi F, de Souza Carvalho FM, Pauletti BA, Leme AFP, Carnielli CM, Selistre‐de‐Araujo HS, Bertolini MC, Ferro JA, Belasque Júnior J, de Oliveira JCF, Novo‐Mansur MTM. Comparative proteomic analysis of Xanthomonas citri ssp. citri periplasmic proteins reveals changes in cellular envelope metabolism during in vitro pathogenicity induction. Mol Plant Pathol 2018; 19:143-157. [PMID: 27798950 PMCID: PMC6638008 DOI: 10.1111/mpp.12507] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
Citrus canker is a plant disease caused by Gram-negative bacteria from the genus Xanthomonas. The most virulent species is Xanthomonas citri ssp. citri (XAC), which attacks a wide range of citrus hosts. Differential proteomic analysis of the periplasm-enriched fraction was performed for XAC cells grown in pathogenicity-inducing (XAM-M) and pathogenicity-non-inducing (nutrient broth) media using two-dimensional electrophoresis combined with liquid chromatography-tandem mass spectrometry. Amongst the 40 proteins identified, transglycosylase was detected in a highly abundant spot in XAC cells grown under inducing condition. Additional up-regulated proteins related to cellular envelope metabolism included glucose-1-phosphate thymidylyltransferase, dTDP-4-dehydrorhamnose-3,5-epimerase and peptidyl-prolyl cis-trans-isomerase. Phosphoglucomutase and superoxide dismutase proteins, known to be involved in pathogenicity in other Xanthomonas species or organisms, were also detected. Western blot and quantitative real-time polymerase chain reaction analyses for transglycosylase and superoxide dismutase confirmed that these proteins were up-regulated under inducing condition, consistent with the proteomic results. Multiple spots for the 60-kDa chaperonin and glyceraldehyde-3-phosphate dehydrogenase were identified, suggesting the presence of post-translational modifications. We propose that substantial alterations in cellular envelope metabolism occur during the XAC infectious process, which are related to several aspects, from defence against reactive oxygen species to exopolysaccharide synthesis. Our results provide new candidates for virulence-related proteins, whose abundance correlates with the induction of pathogenicity and virulence genes, such as hrpD6, hrpG, hrpB7, hpa1 and hrpX. The results present new potential targets against XAC to be investigated in further functional studies.
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Affiliation(s)
- Juliana Artier
- Laboratório de Bioquímica e Biologia Molecular Aplicada, Departamento de Genética e EvoluçãoUniversidade Federal de São Carlos, UFSCarSão CarlosSP13565‐905Brazil
| | - Flávia da Silva Zandonadi
- Laboratório de Bioquímica e Biologia Molecular Aplicada, Departamento de Genética e EvoluçãoUniversidade Federal de São Carlos, UFSCarSão CarlosSP13565‐905Brazil
| | - Flávia Maria de Souza Carvalho
- Departamento de Tecnologia, Faculdade de Ciências Agrárias e Veterinárias de Jaboticabal, UNESPUniversidade Estadual PaulistaJaboticabalSP14884‐900Brazil
| | - Bianca Alves Pauletti
- LNBio, CNPEMLaboratório de Espectrometria de Massas, Laboratório Nacional de BiociênciasCampinasSP13083‐970Brazil
| | - Adriana Franco Paes Leme
- LNBio, CNPEMLaboratório de Espectrometria de Massas, Laboratório Nacional de BiociênciasCampinasSP13083‐970Brazil
| | - Carolina Moretto Carnielli
- Laboratório de Bioquímica e Biologia Molecular Aplicada, Departamento de Genética e EvoluçãoUniversidade Federal de São Carlos, UFSCarSão CarlosSP13565‐905Brazil
| | | | - Maria Célia Bertolini
- Departamento de Bioquímica e Tecnologia Química, Instituto de Química, UNESPUniversidade Estadual PaulistaAraraquaraSP14800‐060Brazil
| | - Jesus Aparecido Ferro
- Departamento de Tecnologia, Faculdade de Ciências Agrárias e Veterinárias de Jaboticabal, UNESPUniversidade Estadual PaulistaJaboticabalSP14884‐900Brazil
| | - José Belasque Júnior
- Departamento de Fitopatologia e Nematologia, Escola Superior de Agricultura ‘Luiz de Queiroz’Universidade de São PauloPiracicabaSP13418‐900Brazil
| | - Julio Cezar Franco de Oliveira
- Laboratório de Interações Microbianas, Departamento de Ciências BiológicasUniversidade Federal de São Paulo, UNIFESPDiademaSP09913‐030Brazil
| | - Maria Teresa Marques Novo‐Mansur
- Laboratório de Bioquímica e Biologia Molecular Aplicada, Departamento de Genética e EvoluçãoUniversidade Federal de São Carlos, UFSCarSão CarlosSP13565‐905Brazil
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Peng A, Chen S, Lei T, Xu L, He Y, Wu L, Yao L, Zou X. Engineering canker-resistant plants through CRISPR/Cas9-targeted editing of the susceptibility gene CsLOB1 promoter in citrus. Plant Biotechnol J 2017; 15:1509-1519. [PMID: 28371200 PMCID: PMC5698050 DOI: 10.1111/pbi.12733] [Citation(s) in RCA: 295] [Impact Index Per Article: 42.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/02/2017] [Revised: 03/16/2017] [Accepted: 03/21/2017] [Indexed: 05/03/2023]
Abstract
Citrus canker, caused by Xanthomonas citri subsp. citri (Xcc), is severely damaging to the global citrus industry. Targeted editing of host disease-susceptibility genes represents an interesting and potentially durable alternative in plant breeding for resistance. Here, we report improvement of citrus canker resistance through CRISPR/Cas9-targeted modification of the susceptibility gene CsLOB1 promoter in citrus. Wanjincheng orange (Citrus sinensis Osbeck) harbours at least three copies of the CsLOB1G allele and one copy of the CsLOB1- allele. The promoter of both alleles contains the effector binding element (EBEPthA4 ), which is recognized by the main effector PthA4 of Xcc to activate CsLOB1 expression to promote citrus canker development. Five pCas9/CsLOB1sgRNA constructs were designed to modify the EBEPthA4 of the CsLOB1 promoter in Wanjincheng orange. Among these constructs, mutation rates were 11.5%-64.7%. Homozygous mutants were generated directly from citrus explants. Sixteen lines that harboured EBEPthA4 modifications were identified from 38 mutant plants. Four mutation lines (S2-5, S2-6, S2-12 and S5-13), in which promoter editing disrupted CsLOB1 induction in response to Xcc infection, showed enhanced resistance to citrus canker compared with the wild type. No canker symptoms were observed in the S2-6 and S5-13 lines. Promoter editing of CsLOB1G alone was sufficient to enhance citrus canker resistance in Wanjincheng orange. Deletion of the entire EBEPthA4 sequence from both CsLOB1 alleles conferred a high degree of resistance to citrus canker. The results demonstrate that CRISPR/Cas9-mediated promoter editing of CsLOB1 is an efficient strategy for generation of canker-resistant citrus cultivars.
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Affiliation(s)
- Aihong Peng
- Citrus Research InstituteChinese Academy of Agricultural Sciences and National Center for Citrus Variety ImprovementChongqingChina
- Citrus Research InstituteSouthwest UniversityChongqingChina
| | - Shanchun Chen
- Citrus Research InstituteChinese Academy of Agricultural Sciences and National Center for Citrus Variety ImprovementChongqingChina
- Citrus Research InstituteSouthwest UniversityChongqingChina
| | - Tiangang Lei
- Citrus Research InstituteChinese Academy of Agricultural Sciences and National Center for Citrus Variety ImprovementChongqingChina
- Citrus Research InstituteSouthwest UniversityChongqingChina
| | - Lanzhen Xu
- Citrus Research InstituteChinese Academy of Agricultural Sciences and National Center for Citrus Variety ImprovementChongqingChina
- Citrus Research InstituteSouthwest UniversityChongqingChina
| | - Yongrui He
- Citrus Research InstituteChinese Academy of Agricultural Sciences and National Center for Citrus Variety ImprovementChongqingChina
- Citrus Research InstituteSouthwest UniversityChongqingChina
| | - Liu Wu
- Citrus Research InstituteSouthwest UniversityChongqingChina
| | - Lixiao Yao
- Citrus Research InstituteChinese Academy of Agricultural Sciences and National Center for Citrus Variety ImprovementChongqingChina
- Citrus Research InstituteSouthwest UniversityChongqingChina
| | - Xiuping Zou
- Citrus Research InstituteChinese Academy of Agricultural Sciences and National Center for Citrus Variety ImprovementChongqingChina
- Citrus Research InstituteSouthwest UniversityChongqingChina
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