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Wang N, Jian W, Liang H, Zhang T, Qi P, Feng Y, Zhou X, Liu L, Yang S. Engineering a biomimicking strategy for discovering nonivamide-based quorum-sensing inhibitors for controlling bacterial infection. Eur J Med Chem 2024; 275:116609. [PMID: 38896993 DOI: 10.1016/j.ejmech.2024.116609] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2024] [Revised: 06/07/2024] [Accepted: 06/15/2024] [Indexed: 06/21/2024]
Abstract
The overuse of antibiotics over an extended period has led to increasing antibiotic resistance in pathogenic bacteria, culminating in what is now considered a global health crisis. To tackle the escalating disaster caused by multidrug-resistant pathogens, the development of new bactericides with new action mechanism is highly necessary. In this study, using a biomimicking strategy, a series of new nonivamide derivatives that feature an isopropanolamine moiety [the structurally similar to the diffusible signal factor (DSF) of Xanthomonas spp.] were prepared for serving as potential quorum-sensing inhibitors (QSIs). After screening and investigation of their rationalizing structure-activity relationships (SARs), compound A26 was discovered as the most optimal active molecule, with EC50 values of 9.91 and 7.04 μg mL-1 against Xanthomonas oryzae pv oryzae (Xoo) and Xanthomonas axonopodis pv. citri (Xac). A docking study showed that compound A26 exhibited robust interactions with Glu A: 161 of RpfF, which was strongly evidenced by fluorescence titration assay (KA value for Xoo RpfF-A26 = 104.8709 M-1). Furthermore, various bioassays showed that compound A26 could inhibit various bacterial virulence factors, including biofilm formation, extracellular polysaccharides (EPS), extracellular enzyme activity, DSF production, and swimming motility. In addition, in vivo anti-Xoo results showed that compound A26 had excellent control efficiency (curative activity: 43.55 %; protective activity: 42.56 %), surpassing that of bismerthiazol and thiodiazole copper by approximately 8.0%-37.3 %. Overall, our findings highlight a new paradigm wherein nonivamide derivatives exhibit potential in combating pathogen resistance issues by inhibiting bacterial quorum sensing systems though attributing to their new molecular skeleton, novel mechanisms of action, and non-toxic features.
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Affiliation(s)
- Na Wang
- State 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
| | - Wujun Jian
- State 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
| | - Hong Liang
- State 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
| | - Taihong Zhang
- State 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
| | - Puying Qi
- State 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
| | - Yumei Feng
- State 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
| | - Xiang Zhou
- State 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.
| | - Liwei Liu
- State 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
| | - Song Yang
- State 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.
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Zhou J, Feng Y, Wu X, Feng Y, Zhao Y, Pan J, Liu S. Communication leads to bacterial heterogeneous adaptation to changing conditions in partial nitrification reactor. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 927:172110. [PMID: 38565348 DOI: 10.1016/j.scitotenv.2024.172110] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/24/2024] [Revised: 03/22/2024] [Accepted: 03/28/2024] [Indexed: 04/04/2024]
Abstract
Recently, it is reported that bacterial communication coordinates the whole consortia to jointly resist the adverse environments. Here, we found the bacterial communication inevitably distinguished bacterial adaptation among different species in partial nitrification reactor under decreasing temperatures. We operated a partial nitrification reactor under temperature gradient from 30 °C to 5 °C and found the promotion of bacterial communication on adaptation of ammonia-oxidizing bacteria (AOB) was greater than that of nitrite-oxidizing bacteria (NOB). Signal pathways with single-component sensing protein in AOB can regulate more genes involved in bacterial adaptation than that with two-component sensing protein in NOB. The negative effects of bacterial communication, which were seriously ignored, have been highlighted, and Clp regulator downstream diffusible signal factor (DSF) based signal pathways worked as transcription activators and inhibitors of adaptation genes in AOB and NOB respectively. Bacterial communication can induce differential adaptation through influencing bacterial interactions. AOB inclined to cooperate with DSF synthesis bacteria as temperature declined, however, cooperation between NOB and DSF synthesis bacteria inclined to get weakening. According to the regulatory effects of signal pathways, bacterial survival strategies for self-protection were revealed. This study hints a potential way to govern niche differentiation in the microbiota by bacterial communication, contributing to forming an efficient artificial ecosystem.
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Affiliation(s)
- Jianhang Zhou
- College of Environmental Sciences and Engineering, Peking University, Beijing 100871, China; Key Laboratory of Water and Sediment Sciences, Ministry of Education of China, Beijing 100871, China
| | - Ying Feng
- College of Environmental Sciences and Engineering, Peking University, Beijing 100871, China; Key Laboratory of Water and Sediment Sciences, Ministry of Education of China, Beijing 100871, China
| | - Xiaogang Wu
- College of Environmental Sciences and Engineering, Peking University, Beijing 100871, China; Key Laboratory of Water and Sediment Sciences, Ministry of Education of China, Beijing 100871, China
| | - Yiming Feng
- College of Environmental Sciences and Engineering, Peking University, Beijing 100871, China; Key Laboratory of Water and Sediment Sciences, Ministry of Education of China, Beijing 100871, China
| | - Yunpeng Zhao
- College of Environmental Sciences and Engineering, Peking University, Beijing 100871, China; Key Laboratory of Water and Sediment Sciences, Ministry of Education of China, Beijing 100871, China
| | - Juejun Pan
- College of Environmental Sciences and Engineering, Peking University, Beijing 100871, China; Key Laboratory of Water and Sediment Sciences, Ministry of Education of China, Beijing 100871, China
| | - Sitong Liu
- College of Environmental Sciences and Engineering, Peking University, Beijing 100871, China; State Environmental Protection Key Laboratory of All Material Fluxes in River Ecosystems, Beijing 100871, China.
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Chang Z, Ma Z, Su Q, Xia X, Ye W, Li R, Lu G. The Transcriptional Regulator TfmR Directly Regulates Two Pathogenic Pathways in Xanthomonas oryzae pv. oryzicola. Int J Mol Sci 2024; 25:5887. [PMID: 38892073 PMCID: PMC11173191 DOI: 10.3390/ijms25115887] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2024] [Revised: 05/17/2024] [Accepted: 05/25/2024] [Indexed: 06/21/2024] Open
Abstract
Xanthomonas oryzae pv. oryzicola (Xoc) is a notorious plant pathogen. Like most bacterial pathogens, Xoc has evolved a complex regulatory network to modulate the expression of various genes related to pathogenicity. Here, we have identified TfmR, a transcriptional regulator belonging to the TetR family, as a key player in the virulence mechanisms of this phytopathogenic bacterium. We have demonstrated genetically that tfmR is involved in the hypersensitive response (HR), pathogenicity, motility and extracellular polysaccharide production of this phytopathogenic bacterium. Our investigations extended to exploring TfmR's interaction with RpfG and HrpX, two prominent virulence regulators in Xanthomonas species. We found that TfmR directly binds to the promoter region of RpfG, thereby positively regulating its expression. Notably, constitutive expression of RpfG partly reinstates the pathogenicity compromised by TfmR-deletion mutants. Furthermore, our studies revealed that TfmR also exerts direct positive regulation on the expression of the T3SS regulator HrpX. Similar to RpfG, sustained expression of HrpX partially restores the pathogenicity of TfmR-deletion mutants. These findings underscore TfmR's multifaceted role as a central regulator governing key virulence pathways in Xoc. Importantly, our research sheds light on the intricate molecular mechanisms underlying the regulation of pathogenicity in this plant pathogen.
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Affiliation(s)
- Zheng Chang
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-Bioresources, College of Life Science and Technology, Guangxi University, Nanning 530004, China; (Z.C.); (Q.S.); (X.X.); (W.Y.)
- Plant Protection Research Institute, Guangxi Academy of Agricultural Science/Key Laboratory of Green Prevention and Control on Fruits and Vegetables in South China Ministry of Agriculture and Rural Affairs/Guangxi Key Laboratory of Biology for Crop Diseases and Insect Pests, Nanning 530007, China
| | - Zengfeng Ma
- Rice Research Institute, Guangxi Academy of Agricultural Sciences, Nanning 530007, China;
| | - Qian Su
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-Bioresources, College of Life Science and Technology, Guangxi University, Nanning 530004, China; (Z.C.); (Q.S.); (X.X.); (W.Y.)
| | - Xinqi Xia
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-Bioresources, College of Life Science and Technology, Guangxi University, Nanning 530004, China; (Z.C.); (Q.S.); (X.X.); (W.Y.)
| | - Wenxin Ye
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-Bioresources, College of Life Science and Technology, Guangxi University, Nanning 530004, China; (Z.C.); (Q.S.); (X.X.); (W.Y.)
| | - Ruifang Li
- Plant Protection Research Institute, Guangxi Academy of Agricultural Science/Key Laboratory of Green Prevention and Control on Fruits and Vegetables in South China Ministry of Agriculture and Rural Affairs/Guangxi Key Laboratory of Biology for Crop Diseases and Insect Pests, Nanning 530007, China
| | - Guangtao Lu
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-Bioresources, College of Life Science and Technology, Guangxi University, Nanning 530004, China; (Z.C.); (Q.S.); (X.X.); (W.Y.)
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Verma RK, Gondu P, Saha T, Chatterjee S. The Global Transcription Regulator XooClp Governs Type IV Pili System-Mediated Bacterial Virulence by Directly Binding to TFP-Chp Promoters to Coordinate Virulence Associated Functions. MOLECULAR PLANT-MICROBE INTERACTIONS : MPMI 2024; 37:357-369. [PMID: 38105438 DOI: 10.1094/mpmi-07-23-0100-r] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/19/2023]
Abstract
Type IV pili (TFP) play a crucial role in the sensing of the external environment for several bacteria. This surface sensing is essential for the lifestyle transitions of several bacteria and involvement in pathogenesis. However, the precise mechanisms underlying TFP's integration of environmental cues, particularly in regulating the TFP-Chp system and its effects on Xanthomonas physiology, social behavior, and virulence, remain poorly understood. In this study, we focused on investigating Clp, a global transcriptional regulator similar to CRP-like proteins, in Xanthomonas oryzae pv. oryzae, a plant pathogen. Our findings reveal that Clp integrates environmental cues detected through diffusible signaling factor (DSF) quorum sensing into the TFP-Chp regulatory system. It accomplishes this by directly binding to TFP-Chp promoters in conjunction with intracellular levels of cyclic-di-GMP, a ubiquitous bacterial second messenger, thereby controlling TFP expression. Moreover, Clp-mediated regulation is involved in regulating several cellular processes, including the production of virulence-associated functions. Collectively, these processes contribute to host colonization and disease initiation. Our study elucidates the intricate regulatory network encompassing Clp, environmental cues, and the TFP-Chp system, providing insights into the molecular mechanisms that drive bacterial virulence in Xanthomonas spp. These findings offer valuable knowledge regarding Xanthomonas pathogenicity and present new avenues for innovative strategies aimed at combating plant diseases caused by these bacteria. [Formula: see text] Copyright © 2024 The Author(s). This is an open access article distributed under the CC BY-NC-ND 4.0 International license.
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Affiliation(s)
- Raj Kumar Verma
- Centre for DNA Fingerprinting and Diagnostics, Uppal, Hyderabad 500039, India
| | - Parimala Gondu
- Centre for DNA Fingerprinting and Diagnostics, Uppal, Hyderabad 500039, India
| | - Tirthankar Saha
- Centre for DNA Fingerprinting and Diagnostics, Uppal, Hyderabad 500039, India
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Zhang A, Zhang H, Wang R, He H, Song B, Song R. Bactericidal bissulfone B 7 targets bacterial pyruvate kinase to impair bacterial biology and pathogenicity in plants. SCIENCE CHINA. LIFE SCIENCES 2024; 67:391-402. [PMID: 37987940 DOI: 10.1007/s11427-023-2449-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/31/2023] [Accepted: 09/11/2023] [Indexed: 11/22/2023]
Abstract
The prevention and control of rice bacterial leaf blight (BLB) disease has not yet been achieved due to the lack of effective agrochemicals and available targets. Herein, we develop a series of novel bissulfones and a novel target with a unique mechanism to address this challenge. The developed bissulfones can control Xanthomonas oryzae pv. oryzae (Xoo), and 2-(bis(methylsulfonyl)methylene)-N-(4-chlorophenyl) hydrazine-1-carboxamide (B7) is more effective than the commercial drugs thiodiazole copper (TC) and bismerthiazol (BT). Pyruvate kinase (PYK) in Xoo has been identified for the first time as the target protein of our bissulfone B7. PYK modulates bacterial virulence via a CRP-like protein (Clp)/two-component system regulatory protein (regR) axis. The elucidation of this pathway facilitates the use of B7 to reduce PYK expression at the transcriptional level, block PYK activity at the protein level, and impair the interaction within the PYK-Clp-regR complex via competitive inhibition, thereby attenuating bacterial biology and pathogenicity. This study offers insights into the molecular and mechanistic aspects underlying anti-Xoo strategies that target PYK. We believe that these valuable discoveries will be used for bacterial disease control in the future.
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Affiliation(s)
- Awei 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
| | - Haizhen 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
| | - Ronghua 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
| | - Hongfu He
- 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
| | - Baoan Song
- 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.
| | - Runjiang Song
- 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.
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6
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Kalia M, Amari D, Davies DG, Sauer K. cis-DA-dependent dispersion by Pseudomonas aeruginosa biofilm and identification of cis-DA-sensory protein DspS. mBio 2023; 14:e0257023. [PMID: 38014955 PMCID: PMC10746223 DOI: 10.1128/mbio.02570-23] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2023] [Accepted: 10/11/2023] [Indexed: 11/29/2023] Open
Abstract
IMPORTANCE Dispersion is an essential stage of the biofilm life cycle resulting in the release of bacteria from a biofilm into the surrounding environment. Dispersion contributes to bacterial survival by relieving overcrowding within a biofilm and allowing dissemination of cells into new habitats for colonization. Thus, dispersion can contribute to biofilm survival as well as disease progression and transmission. Cells dispersed from a biofilm rapidly lose their recalcitrant antimicrobial-tolerant biofilm phenotype and transition to a state that is susceptible to antibiotics. However, much of what is known about this biofilm developmental stage has been inferred from exogenously induced dispersion. Our findings provide the first evidence that native dispersion is coincident with reduced cyclic dimeric guanosine monophosphate levels, while also relying on at least some of the same factors that are central to the environmentally induced dispersion response, namely, BdlA, DipA, RbdA, and AmrZ. Additionally, we demonstrate for the first time that cis-DA signaling to induce dispersion is attributed to the two-component sensor/response regulator DspS, a homolog of the DSF sensor RpfC. Our findings also provide a path toward manipulating the native dispersion response as a novel and highly promising therapeutic intervention.
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Affiliation(s)
- Manmohit Kalia
- Department of Biological Sciences, Binghamton University, Binghamton, New York, USA
- Binghamton Biofilm Research Center, Binghamton University, Binghamton, New York, USA
| | - Diana Amari
- Department of Biological Sciences, Binghamton University, Binghamton, New York, USA
- Binghamton Biofilm Research Center, Binghamton University, Binghamton, New York, USA
| | - David G. Davies
- Department of Biological Sciences, Binghamton University, Binghamton, New York, USA
- Binghamton Biofilm Research Center, Binghamton University, Binghamton, New York, USA
| | - Karin Sauer
- Department of Biological Sciences, Binghamton University, Binghamton, New York, USA
- Binghamton Biofilm Research Center, Binghamton University, Binghamton, New York, USA
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Zhang YQ, Song XY, Liu F. XanFur, a novel Fur protein induced by H 2O 2, positively regulated by the global transcriptional regulator Clp and required for the full virulence of Xanthomonas oryzae pv. oryzae in rice. Microbiol Spectr 2023; 11:e0118723. [PMID: 37831462 PMCID: PMC10714925 DOI: 10.1128/spectrum.01187-23] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2023] [Accepted: 08/07/2023] [Indexed: 10/14/2023] Open
Abstract
IMPORTANCE Although Xanthomonas oryzae pv. oryzae (Xoo) has been found to be a bacterial pathogen causing bacterial leaf blight in rice for many years, the molecular mechanisms of the rice-Xoo interaction has not been fully understood. In this study, we found that XanFur of Xoo is a novel ferric uptake regulator (Fur) protein conserved among major pathogenic Xanthomonas species. XanFur is required for the virulence of Xoo in rice, and likely involved in regulating the virulence determinants of Xoo. The expression of xanfur is induced by H2O2, and positively regulated by the global transcriptional regulator Clp. Our results reveal the function and regulation of the novel virulence-related Fur protein XanFur in Xoo, providing new insights into the interaction mechanisms of rice-Xoo.
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Affiliation(s)
- Yu-Qiang Zhang
- Institute of Plant Protection, Jiangsu Academy of Agricultural Sciences, Nanjing, Jiangsu, China
- State Key Laboratory of Microbial Technology, Shandong University, Qingdao, Shandong, China
| | - Xiao-Yan Song
- State Key Laboratory of Microbial Technology, Shandong University, Qingdao, Shandong, China
| | - Fengquan Liu
- Institute of Plant Protection, Jiangsu Academy of Agricultural Sciences, Nanjing, Jiangsu, China
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Lv L, Chen J, Liu X, Gao W, Sun L, Wang P, Ren Z, Zhang G, Li W. Roles and regulation of quorum sensing in anaerobic granular sludge: Research status, challenges, and perspectives. BIORESOURCE TECHNOLOGY 2023; 387:129644. [PMID: 37558106 DOI: 10.1016/j.biortech.2023.129644] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/20/2023] [Revised: 07/31/2023] [Accepted: 08/05/2023] [Indexed: 08/11/2023]
Abstract
Anaerobic granular sludge (AnGS) has a complex and important internal microbial communication system due to its unique microbial layered structure. As a concentration-dependent communication system between bacterial cells through signal molecules, QS (quorum sensing) is widespread in AnGS and exhibits great potential to regulate microbial behaviors. Therefore, the universal functions of QS in AnGS have been systematically summarized in this paper, including the influence on the metabolic activity, physicochemical properties, and microbial community of AnGS. Subsequently, the common QS-based AnGS regulation approaches are reviewed and analyzed comprehensively. The regulation mechanism of QS in AnGS is analyzed from two systems of single bacterium and mixed bacteria. This review can provide a comprehensive understanding of QS functions in AnGS systems, and promote the practical application of QS-based strategies in optimization of AnGS treatment process.
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Affiliation(s)
- Longyi Lv
- Tianjin Key Laboratory of Clean Energy and Pollution Control, School of Energy and Environmental Engineering, Hebei University of Technology, Tianjin 300401, PR China
| | - Jiarui Chen
- Tianjin Key Laboratory of Clean Energy and Pollution Control, School of Energy and Environmental Engineering, Hebei University of Technology, Tianjin 300401, PR China
| | - Xiaoyang Liu
- Tianjin Key Laboratory of Clean Energy and Pollution Control, School of Energy and Environmental Engineering, Hebei University of Technology, Tianjin 300401, PR China.
| | - Wenfang Gao
- Tianjin Key Laboratory of Clean Energy and Pollution Control, School of Energy and Environmental Engineering, Hebei University of Technology, Tianjin 300401, PR China
| | - Li Sun
- Tianjin Key Laboratory of Clean Energy and Pollution Control, School of Energy and Environmental Engineering, Hebei University of Technology, Tianjin 300401, PR China
| | - Pengfei Wang
- Tianjin Key Laboratory of Clean Energy and Pollution Control, School of Energy and Environmental Engineering, Hebei University of Technology, Tianjin 300401, PR China
| | - Zhijun Ren
- Tianjin Key Laboratory of Clean Energy and Pollution Control, School of Energy and Environmental Engineering, Hebei University of Technology, Tianjin 300401, PR China
| | - Guangming Zhang
- Tianjin Key Laboratory of Clean Energy and Pollution Control, School of Energy and Environmental Engineering, Hebei University of Technology, Tianjin 300401, PR China
| | - Weiguang Li
- State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology (SKLUWRE, HIT), Harbin 150090, PR China.
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9
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Dutta K, Shityakov S, Maruyama F. DSF inactivator RpfB homologous FadD upregulated in Bradyrhizobium japonicum under iron limiting conditions. Sci Rep 2023; 13:8701. [PMID: 37248242 DOI: 10.1038/s41598-023-35487-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2022] [Accepted: 05/18/2023] [Indexed: 05/31/2023] Open
Abstract
Phytopathogenic bacteria Xanthomonas campestris pv. campestris (Xcc) causes black rot and other plant diseases. Xcc senses diffusible signal factor (DSF) as a quorum-sensing (QS) signal that mediates mainly iron uptake and virulence. RpfB deactivates DSF in this DSF-QS circuit. We examined differential gene expression profiles of Bradyrhizobium japonicum under low versus high iron conditions and found that fadD and irr were upregulated under low iron (log2 fold change 0.825 and 1.716, respectively). In addition to having similar protein folding patterns and functional domain similarities, FadD shared 58% sequence similarity with RpfB of Xcc. The RpfB-DSF and FadD-DSF complexes had SWISSDock molecular docking scores of - 8.88 kcal/mol and - 9.85 kcal/mol, respectively, and the 100 ns molecular dynamics simulation results were in accord with the docking results. However, significant differences were found between the binding energies of FadD-DSF and RpfB-DSF, indicating possible FadD-dependent DSF turnover. The protein-protein interaction network showed that FadD connected indirectly with ABC transporter permease (ABCtp), which was also upregulated (log2 fold change 5.485). We speculate that the low iron condition may be a mimetic environmental stimulus for fadD upregulation in B. japonicum to deactivate DSF, inhibit iron uptake and virulence of DSF-producing neighbors. This finding provides a new option of using B. japonicum or a genetically improved B. japonicum as a potential biocontrol agent against Xcc, with the added benefit of plant growth-promoting properties.
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Affiliation(s)
- Kunal Dutta
- Laboratory of Chemoinformatics, Infochemistry Scientific Center, ITMO University, Saint Petersburg, Russian Federation.
| | - Sergey Shityakov
- Laboratory of Chemoinformatics, Infochemistry Scientific Center, ITMO University, Saint Petersburg, Russian Federation.
| | - Fumito Maruyama
- Microbial Genomics and Ecology, The IDEC Institute, Hiroshima University, Higashihiroshima, Japan.
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Pan J, Zhou J, Tang X, Guo Y, Zhao Y, Liu S. Bacterial Communication Coordinated Behaviors of Whole Communities to Cope with Environmental Changes. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2023; 57:4253-4265. [PMID: 36862939 DOI: 10.1021/acs.est.2c05780] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/18/2023]
Abstract
Bacterial communication plays an important role in coordinating microbial behaviors in a community. However, how bacterial communication organizes the entire community for anaerobes to cope with varied anaerobic-aerobic conditions remains unclear. We constructed a local bacterial communication gene (BCG) database comprising 19 BCG subtypes and 20279 protein sequences. BCGs in anammox-partial nitrification consortia coping with intermittent aerobic and anaerobic conditions as well as gene expressions of 19 species were inspected. We found that when suffering oxygen changes, intra- and interspecific communication by a diffusible signal factor (DSF) and bis-(3'-5')-cyclic dimeric guanosine monophosphate (c-di-GMP) changed first, which in turn induced changes of autoinducer-2 (AI-2)-based interspecific and acyl homoserine lactone (AHLs)-based intraspecific communication. DSF and c-di-GMP-based communication regulated 455 genes, which covered 13.64% of the genomes and were mainly involved in antioxidation and metabolite residue degradation. For anammox bacteria, oxygen influenced DSF and c-di-GMP-based communication through RpfR to upregulate antioxidant proteins, oxidative damage-repairing proteins, peptidases, and carbohydrate-active enzymes, which benefited their adaptation to oxygen changes. Meanwhile, other bacteria also enhanced DSF and c-di-GMP-based communication by synthesizing DSF, which helped anammox bacteria survive at aerobic conditions. This study evidences the role of bacterial communication as an "organizer" within consortia to cope with environmental changes and sheds light on understanding bacterial behaviors from the perspective of sociomicrobiology.
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Affiliation(s)
- Juejun Pan
- Department of Environmental Engineering, College of Environmental Sciences and Engineering, Peking University, Beijing 100871, China
- Key Laboratory of Water and Sediment Sciences, Ministry of Education of China, Peking University, Beijing 100871, China
| | - Jianhang Zhou
- Department of Environmental Engineering, College of Environmental Sciences and Engineering, Peking University, Beijing 100871, China
- Key Laboratory of Water and Sediment Sciences, Ministry of Education of China, Peking University, Beijing 100871, China
| | - Xi Tang
- Department of Environmental Engineering, College of Environmental Sciences and Engineering, Peking University, Beijing 100871, China
- Key Laboratory of Water and Sediment Sciences, Ministry of Education of China, Peking University, Beijing 100871, China
| | - Yongzhao Guo
- Department of Environmental Engineering, College of Environmental Sciences and Engineering, Peking University, Beijing 100871, China
- Key Laboratory of Water and Sediment Sciences, Ministry of Education of China, Peking University, Beijing 100871, China
| | - Yunpeng Zhao
- Department of Environmental Engineering, College of Environmental Sciences and Engineering, Peking University, Beijing 100871, China
- Key Laboratory of Water and Sediment Sciences, Ministry of Education of China, Peking University, Beijing 100871, China
| | - Sitong Liu
- Department of Environmental Engineering, College of Environmental Sciences and Engineering, Peking University, Beijing 100871, China
- Key Laboratory of Water and Sediment Sciences, Ministry of Education of China, Peking University, Beijing 100871, China
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11
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Zhu X, Chen WJ, Bhatt K, Zhou Z, Huang Y, Zhang LH, Chen S, Wang J. Innovative microbial disease biocontrol strategies mediated by quorum quenching and their multifaceted applications: A review. FRONTIERS IN PLANT SCIENCE 2023; 13:1063393. [PMID: 36714722 PMCID: PMC9878147 DOI: 10.3389/fpls.2022.1063393] [Citation(s) in RCA: 12] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/17/2022] [Accepted: 12/15/2022] [Indexed: 06/12/2023]
Abstract
With the increasing resistance exhibited by undesirable bacteria to traditional antibiotics, the need to discover alternative (or, at least, supplementary) treatments to combat chemically resistant bacteria is becoming urgent. Quorum sensing (QS) refers to a novel bacterial communication system for monitoring cell density and regulation of a network of gene expression that is mediated by a group of signaling molecules called autoinducers (AIs). QS-regulated multicellular behaviors include biofilm formation, horizontal gene transfer, and antibiotic synthesis, which are demonstrating increasing pathogenicity to plants and aquacultural animals as well as contamination of wastewater treatment devices. To inhibit QS-regulated microbial behaviors, the strategy of quorum quenching (QQ) has been developed. Different quorum quenchers interfere with QS through different mechanisms, such as competitively inhibiting AI perception (e.g., by QS inhibitors) and AI degradation (e.g., by QQ enzymes). In this review, we first introduce different signaling molecules, including diffusible signal factor (DSF) and acyl homoserine lactones (AHLs) for Gram-negative bacteria, AIPs for Gram-positive bacteria, and AI-2 for interspecies communication, thus demonstrating the mode of action of the QS system. We next exemplify the QQ mechanisms of various quorum quenchers, such as chemical QS inhibitors, and the physical/enzymatic degradation of QS signals. We devote special attention to AHL-degrading enzymes, which are categorized in detail according to their diverse catalytic mechanisms and enzymatic properties. In the final part, the applications and advantages of quorum quenchers (especially QQ enzymes and bacteria) are summarized in the context of agricultural/aquacultural pathogen biocontrol, membrane bioreactors for wastewater treatment, and the attenuation of human pathogenic bacteria. Taken together, we present the state-of-the-art in research considering QS and QQ, providing theoretical evidence and support for wider application of this promising environmentally friendly biocontrol strategy.
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Affiliation(s)
- Xixian Zhu
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-bioresources, Guangdong Province Key Laboratory of Microbial Signals and Disease Control, Integrative Microbiology Research Centre, South China Agricultural University, Guangzhou, China
- Guangdong Laboratory for Lingnan Modern Agriculture, College of Plant Protection, South China Agricultural University, Guangzhou, China
| | - Wen-Juan Chen
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-bioresources, Guangdong Province Key Laboratory of Microbial Signals and Disease Control, Integrative Microbiology Research Centre, South China Agricultural University, Guangzhou, China
- Guangdong Laboratory for Lingnan Modern Agriculture, College of Plant Protection, South China Agricultural University, Guangzhou, China
| | - Kalpana Bhatt
- Department of Food Science, Purdue University, West Lafayette, IN, United States
| | - Zhe Zhou
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-bioresources, Guangdong Province Key Laboratory of Microbial Signals and Disease Control, Integrative Microbiology Research Centre, South China Agricultural University, Guangzhou, China
- Guangdong Laboratory for Lingnan Modern Agriculture, College of Plant Protection, South China Agricultural University, Guangzhou, China
| | - Yaohua Huang
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-bioresources, Guangdong Province Key Laboratory of Microbial Signals and Disease Control, Integrative Microbiology Research Centre, South China Agricultural University, Guangzhou, China
- Guangdong Laboratory for Lingnan Modern Agriculture, College of Plant Protection, South China Agricultural University, Guangzhou, China
| | - Lian-Hui Zhang
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-bioresources, Guangdong Province Key Laboratory of Microbial Signals and Disease Control, Integrative Microbiology Research Centre, South China Agricultural University, Guangzhou, China
- Guangdong Laboratory for Lingnan Modern Agriculture, College of Plant Protection, South China Agricultural University, Guangzhou, China
| | - Shaohua Chen
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-bioresources, Guangdong Province Key Laboratory of Microbial Signals and Disease Control, Integrative Microbiology Research Centre, South China Agricultural University, Guangzhou, China
- Guangdong Laboratory for Lingnan Modern Agriculture, College of Plant Protection, South China Agricultural University, Guangzhou, China
| | - Junxia Wang
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-bioresources, Guangdong Province Key Laboratory of Microbial Signals and Disease Control, Integrative Microbiology Research Centre, South China Agricultural University, Guangzhou, China
- Guangdong Laboratory for Lingnan Modern Agriculture, College of Plant Protection, South China Agricultural University, Guangzhou, China
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12
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He YW, Deng Y, Miao Y, Chatterjee S, Tran TM, Tian J, Lindow S. DSF-family quorum sensing signal-mediated intraspecies, interspecies, and inter-kingdom communication. Trends Microbiol 2023; 31:36-50. [PMID: 35941062 DOI: 10.1016/j.tim.2022.07.006] [Citation(s) in RCA: 25] [Impact Index Per Article: 25.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2022] [Revised: 07/17/2022] [Accepted: 07/19/2022] [Indexed: 11/28/2022]
Abstract
While most bacteria are unicellular microbes they communicate with each other and with their environments to adapt their behaviors. Quorum sensing (QS) is one of the best-studied cell-cell communication modes. QS signaling is not restricted to bacterial cell-to-cell communication - it also allows communication between bacteria and their eukaryotic hosts. The diffusible signal factor (DSF) family represents an intriguing type of QS signal with multiple roles found in diverse Gram-negative bacteria. Over the last decade, extensive progress has been made in understanding DSF-mediated communication among bacteria, fungi, insects, plants, and zebrafish. This review provides an update on these new developments with the aim of building a more comprehensive picture of DSF-mediated intraspecies, interspecies, and inter-kingdom communication.
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Affiliation(s)
- Ya-Wen He
- State Key Laboratory of Microbial Metabolism, Joint International Research Laboratory of Metabolic and Developmental Sciences, School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai 200240, China.
| | - Yinyue Deng
- School of Pharmaceutical Science (Shenzhen), Sun Yat-Sen University, Shenzhen 518107, China
| | - Yansong Miao
- School of Biological Science, Nanyang Technological University, Singapore
| | | | - Tuan Minh Tran
- Department of Biology, University of South Alabama, Mobile, AL 36688, USA
| | - Jing Tian
- The College of Life Sciences, Northwest University, Xi'an 710069, China
| | - Steven Lindow
- Department of Plant and Microbial Biology, University of California Berkeley, CA 94720, USA
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13
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Luneau JS, Baudin M, Quiroz Monnens T, Carrère S, Bouchez O, Jardinaud M, Gris C, François J, Ray J, Torralba B, Arlat M, Lewis JD, Lauber E, Deutschbauer AM, Noël LD, Boulanger A. Genome-wide identification of fitness determinants in the Xanthomonas campestris bacterial pathogen during early stages of plant infection. THE NEW PHYTOLOGIST 2022; 236:235-248. [PMID: 35706385 PMCID: PMC9543026 DOI: 10.1111/nph.18313] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/28/2022] [Accepted: 06/07/2022] [Indexed: 05/31/2023]
Abstract
Plant diseases are an important threat to food production. While major pathogenicity determinants required for disease have been extensively studied, less is known on how pathogens thrive during host colonization, especially at early infection stages. Here, we used randomly barcoded-transposon insertion site sequencing (RB-TnSeq) to perform a genome-wide screen and identify key bacterial fitness determinants of the vascular pathogen Xanthomonas campestris pv campestris (Xcc) during infection of the cauliflower host plant (Brassica oleracea). This high-throughput analysis was conducted in hydathodes, the natural entry site of Xcc, in xylem sap and in synthetic media. Xcc did not face a strong bottleneck during hydathode infection. In total, 181 genes important for fitness were identified in plant-associated environments with functional enrichment in genes involved in metabolism but only few genes previously known to be involved in virulence. The biological relevance of 12 genes was independently confirmed by phenotyping single mutants. Notably, we show that XC_3388, a protein with no known function (DUF1631), plays a key role in the adaptation and virulence of Xcc possibly through c-di-GMP-mediated regulation. This study revealed yet unsuspected social behaviors adopted by Xcc individuals when confined inside hydathodes at early infection stages.
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Affiliation(s)
- Julien S. Luneau
- LIPME, Université de Toulouse, INRAE, CNRSUniversité Paul Sabatier31320Castanet‐TolosanFrance
| | - Maël Baudin
- Plant Gene Expression Center, USDAAlbanyCA94710USA
- Department of Plant and Microbial BiologyUniversity of CaliforniaBerkeleyCA94720USA
| | - Thomas Quiroz Monnens
- LIPME, Université de Toulouse, INRAE, CNRSUniversité Paul Sabatier31320Castanet‐TolosanFrance
| | - Sébastien Carrère
- LIPME, Université de Toulouse, INRAE, CNRSUniversité Paul Sabatier31320Castanet‐TolosanFrance
| | - Olivier Bouchez
- Genotoul Genome & Transcriptome (GeT‐PlaGe), INRAE31320Castanet‐TolosanFrance
| | | | - Carine Gris
- LIPME, Université de Toulouse, INRAE, CNRSUniversité Paul Sabatier31320Castanet‐TolosanFrance
| | - Jonas François
- LIPME, Université de Toulouse, INRAE, CNRSUniversité Paul Sabatier31320Castanet‐TolosanFrance
| | - Jayashree Ray
- Environmental Genomics and Systems Biology DivisionLawrence Berkeley National LaboratoryBerkeleyCA94720USA
| | - Babil Torralba
- LIPME, Université de Toulouse, INRAE, CNRSUniversité Paul Sabatier31320Castanet‐TolosanFrance
| | - Matthieu Arlat
- LIPME, Université de Toulouse, INRAE, CNRSUniversité Paul Sabatier31320Castanet‐TolosanFrance
| | - Jennifer D. Lewis
- Plant Gene Expression Center, USDAAlbanyCA94710USA
- Department of Plant and Microbial BiologyUniversity of CaliforniaBerkeleyCA94720USA
| | - Emmanuelle Lauber
- LIPME, Université de Toulouse, INRAE, CNRSUniversité Paul Sabatier31320Castanet‐TolosanFrance
| | - Adam M. Deutschbauer
- Department of Plant and Microbial BiologyUniversity of CaliforniaBerkeleyCA94720USA
- Environmental Genomics and Systems Biology DivisionLawrence Berkeley National LaboratoryBerkeleyCA94720USA
| | - Laurent D. Noël
- LIPME, Université de Toulouse, INRAE, CNRSUniversité Paul Sabatier31320Castanet‐TolosanFrance
| | - Alice Boulanger
- LIPME, Université de Toulouse, INRAE, CNRSUniversité Paul Sabatier31320Castanet‐TolosanFrance
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14
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Wang Y, Bian Z, Wang Y. Biofilm formation and inhibition mediated by bacterial quorum sensing. Appl Microbiol Biotechnol 2022; 106:6365-6381. [DOI: 10.1007/s00253-022-12150-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2022] [Revised: 08/23/2022] [Accepted: 08/24/2022] [Indexed: 11/25/2022]
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15
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Dual Regulatory Role Exerted by Cyclic Dimeric GMP To Control FsnR-Mediated Bacterial Swimming. mBio 2022; 13:e0141422. [PMID: 36069448 DOI: 10.1128/mbio.01414-22] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Bacterial motility has great medical and ecological significance because of its essential role in bacterial survival and pathogenesis. Cyclic dimeric GMP (c-di-GMP), a second messenger in bacteria, is the predominant regulator of flagellar synthesis and motility and possesses turnover mechanisms that have been thoroughly investigated. Therefore, much attention has been focused on identifying the upstream stimulatory signals and downstream modules that respond to altered c-di-GMP levels. Here, we systematically analyzed c-di-GMP cyclases and phosphodiesterases in Stenotrophomonas maltophilia to screen for motility regulators. Of these enzymes, we identified and characterized a new phosphodiesterase named SisP, which was found to facilitate bacterial swimming upon stimulation with ferrous iron. SisP-mediated degradation of c-di-GMP leads to FsnR-dependent transcription of flagellar genes. Remarkably, c-di-GMP controls FsnR via two independent mechanisms: by direct binding and indirectly by modulating its phosphorylation state. In this study, we deciphered a novel "one stone, two birds" regulatory strategy of c-di-GMP and uncovered the signal that stimulates c-di-GMP hydrolysis. Facilitation of bacterial swimming motility by ferrous iron might contribute to the higher risk of bacterial infection in acutely ill patients. IMPORTANCE Stenotrophomonas maltophilia has become a great threat to human health because of the high mortality of infected patients. Swimming motility plays a crucial role in regulating bacterial virulence and adaptation. However, limited progress has been made in cyclic dimeric GMP (c-di-GMP) controlling swimming motility of S. maltophilia. Here, we characterized c-di-GMP turnover enzymes encoded by S. maltophilia and dissected the regulatory details of a phosphodiesterase named SisP. We demonstrated that SisP degrades c-di-GMP to fully activate FsnR through directly releasing FsnR from the FsnR-c-di-GMP complex and indirectly increasing its phosphorylation level. This finding uncovered a quantitative, rather than an on-off, regulatory manner employed by c-di-GMP to regulate activities of its effectors. Identification of the specific activation of SisP by ferrous iron proposes SisP as a putative drug-target for controlling bacterial infection and ferrous iron at the wounds or cuts as a putative factor contributing to the higher risk of bacterial infection.
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16
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Zhang A, Song R, Wang R, Li H, Hu D, Song B. Synthesis and Antibacterial Activities of 2- Oxo- N-phenylacetamide Derivatives Containing a Dissulfone Moiety Target on Clp. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2022; 70:9356-9366. [PMID: 35862796 DOI: 10.1021/acs.jafc.2c02605] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
Rice bacterial blight and rice bacterial streak are two serious rice diseases and have caused great harm to the production of rice all over the world. To develop an efficient antibacterial agent with a novel target, a series of novel 2-oxo-N-phenylacetamide derivatives containing a dissulfone moiety were synthesized, and their antibacterial activities were evaluated. Among them, compound D14 exhibited the best antibacterial activities, especially against Xoo and Xoc with EC50 values of 0.63 and 0.79 mg/L, respectively, which were much better than the commercial control of bismerthiazol (BT) (76.59 and 83.35 mg/L, respectively) and thiodiazole copper (TC) (91.72 and 114.00 mg/L, respectively). Meanwhile, compound D14 can interact with a CRP-like protein (Clp) of Pxo99A and show strong binding activity with Xoo-Clp with a Kd value of 0.52 μM, which was far superior to the corresponding Kd values of BT (183.94 μM) and TC (222.58 μM). Treatment of D14 and deletion of the clp gene could significantly reduce the expression of the clp gene and attenuate the virulence of pathogenic bacteria. These results indicated that compound D14 could be used as a potential novel agricultural bactericide and Clp can be used as a target protein for the control of plant bacterial diseases. This work provided reliable support for developing novel antibacterial agents based on Clp as a target protein.
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Affiliation(s)
- Awei Zhang
- State Key Laboratory Breeding Base of Green Pesticide and Agricultural Bioengineering, Key Laboratory of Green Pesticide and Agricultural Bioengineering, Ministry of Education, Guizhou University, Huaxi District, Guiyang 550025, China
| | - Runjiang Song
- State Key Laboratory Breeding Base of Green Pesticide and Agricultural Bioengineering, Key Laboratory of Green Pesticide and Agricultural Bioengineering, Ministry of Education, Guizhou University, Huaxi District, Guiyang 550025, China
| | - Ronghua Wang
- State Key Laboratory Breeding Base of Green Pesticide and Agricultural Bioengineering, Key Laboratory of Green Pesticide and Agricultural Bioengineering, Ministry of Education, Guizhou University, Huaxi District, Guiyang 550025, China
| | - Hongde Li
- State Key Laboratory Breeding Base of Green Pesticide and Agricultural Bioengineering, Key Laboratory of Green Pesticide and Agricultural Bioengineering, Ministry of Education, Guizhou University, Huaxi District, Guiyang 550025, China
| | - Deyu Hu
- State Key Laboratory Breeding Base of Green Pesticide and Agricultural Bioengineering, Key Laboratory of Green Pesticide and Agricultural Bioengineering, Ministry of Education, Guizhou University, Huaxi District, Guiyang 550025, China
| | - Baoan Song
- State Key Laboratory Breeding Base of Green Pesticide and Agricultural Bioengineering, Key Laboratory of Green Pesticide and Agricultural Bioengineering, Ministry of Education, Guizhou University, Huaxi District, Guiyang 550025, China
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17
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Li Y, Feng T, Wang Y. The role of bacterial signaling networks in antibiotics response and resistance regulation. MARINE LIFE SCIENCE & TECHNOLOGY 2022; 4:163-178. [PMID: 37073223 PMCID: PMC10077285 DOI: 10.1007/s42995-022-00126-1] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 08/25/2021] [Accepted: 01/07/2022] [Indexed: 05/03/2023]
Abstract
Excessive use of antibiotics poses a threat to public health and the environment. In ecosystems, such as the marine environment, antibiotic contamination has led to an increase in bacterial resistance. Therefore, the study of bacterial response to antibiotics and the regulation of resistance formation have become an important research field. Traditionally, the processes related to antibiotic responses and resistance regulation have mainly included the activation of efflux pumps, mutation of antibiotic targets, production of biofilms, and production of inactivated or passivation enzymes. In recent years, studies have shown that bacterial signaling networks can affect antibiotic responses and resistance regulation. Signaling systems mostly alter resistance by regulating biofilms, efflux pumps, and mobile genetic elements. Here we provide an overview of how bacterial intraspecific and interspecific signaling networks affect the response to environmental antibiotics. In doing so, this review provides theoretical support for inhibiting bacterial antibiotic resistance and alleviating health and ecological problems caused by antibiotic contamination.
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Affiliation(s)
- Yuying Li
- College of Marine Life Sciences, Ocean University of China, Qingdao, 266003 China
- Institute of Evolution and Marine Biodiversity, Ocean University of China, Qingdao, 266003 China
| | - Tao Feng
- College of Marine Life Sciences, Ocean University of China, Qingdao, 266003 China
- Institute of Evolution and Marine Biodiversity, Ocean University of China, Qingdao, 266003 China
| | - Yan Wang
- College of Marine Life Sciences, Ocean University of China, Qingdao, 266003 China
- Institute of Evolution and Marine Biodiversity, Ocean University of China, Qingdao, 266003 China
- Laboratory for Marine Ecology and Environmental Science, National Laboratory for Marine Science and Technology (Qingdao), Qingdao, 266071 China
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18
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Wang X, Zhang X, Lu BH, Gao J. The periplasmic chaperone protein Psg_2795 contributes to the virulence of Pseudomonas savastanoi pv. glycinea: the causal agent of bacterial blight of soybean. J Microbiol 2022; 60:478-487. [PMID: 35246805 DOI: 10.1007/s12275-022-1469-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2021] [Revised: 01/10/2022] [Accepted: 01/12/2022] [Indexed: 11/29/2022]
Abstract
Pseudomonas savastanoi pv. glycinea (Psg also named P. syringae pv. glycinea and P. amygdali pv. glycinea) is the causative agent of bacterial blight in soybean. The identification of virulence factors is essential for understanding the pathogenesis of Psg. In this study, a mini-Tn5 transposon mutant library of Psg strain PsgNC12 was screened on soybean, and one low-virulent mini-Tn5 mutant, designated as 4573, was identified. Sequence analysis of the 4573-mutant revealed that the mini-Tn5 transposon was inserted in the Psg_2795 gene. Psg_2795 encodes a FimC-domain protein that is highly conserved in Pseudomonas. Further analysis revealed that the mutation and knockout of Psg_2795 results in a reduced virulence phenotype on soybean, decreased motility, weakened bacterial attachment to a glass surface and delayed the population growth within soybean leaves. The phenotype of the 4573-mutant could be complemented nearly to wild-type levels using an intact Psg_2795 gene. Collectively, our results demonstrate that Psg_2795 plays an important role in the virulence, motility, attachment and the population growth of PsgNC12 in soybean. This finding provides a new insight into the function of periplasmic chaperone proteins in a type I pilus and provides reference information for identifying Psg_2795 homologues in P. savastanoi and other bacteria.
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Affiliation(s)
- Xiuhua Wang
- College of Plant Protection, Jilin Agricultural University, Changchun, 130118, P. R. China
| | - Xiaoyan Zhang
- College of Plant Protection, Jilin Agricultural University, Changchun, 130118, P. R. China
| | - Bao-Hui Lu
- College of Plant Protection, Jilin Agricultural University, Changchun, 130118, P. R. China.
| | - Jie Gao
- College of Plant Protection, Jilin Agricultural University, Changchun, 130118, P. R. China.
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The Plant Defense Signal Salicylic Acid Activates the RpfB-Dependent Quorum Sensing Signal Turnover via Altering the Culture and Cytoplasmic pH in the Phytopathogen Xanthomonas campestris. mBio 2022; 13:e0364421. [PMID: 35254135 PMCID: PMC9040794 DOI: 10.1128/mbio.03644-21] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023] Open
Abstract
Plant colonization by phytopathogens is a very complex process in which numerous factors are involved. Upon infection by phytopathogens, plants produce salicylic acid (SA) that triggers gene expression within the plant to counter the invading pathogens. The present study demonstrated that SA signal also directly acts on the quorum-sensing (QS) system of the invading pathogen Xanthomonas campestris pv. campestris to affect its virulence by inducing turnover of the diffusible signaling factor (DSF) family QS signal. First, Xanthomonas campestris pv. campestris infection induces SA biosynthesis in the cabbage host plant. SA cannot be degraded by Xanthomonas campestris pv. campestris during culturing. Exogenous addition of SA or endogenous production of SA induces DSF signal turnover during late growth phase of Xanthomonas campestris pv. campestris in XYS medium that mimics plant vascular environments. Further, the DSF turnover gene rpfB is required for SA induction of DSF turnover. However, SA does not affect the expression of rpfB and DSF biosynthesis gene rpfF at the transcriptional level. SA induction of DSF turnover only occurs under acidic conditions in XYS medium. Furthermore, addition of SA to XYS medium significantly increased both culture and cytoplasmic pH. Increased cytoplasmic pH induced DSF turnover in a rpfB-dependent manner. In vitro RpfB-dependent DSF turnover activity increased when pH increased from 6 to 8. SA exposure did not affect the RpfB-dependent DSF turnover in vitro. Finally, SA-treated Xanthomonas campestris pv. campestris strain exhibited enhanced virulence when inoculated on cabbage. These results provide new insight into the roles of SA in host plants and the molecular interactions between Xanthomonas campestris pv. campestris and cruciferous plants.
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Lin M, Wu K, Zhan Z, Mi D, Xia Y, Niu X, Feng S, Chen Y, He C, Tao J, Li C. The RavA/VemR two-component system plays vital regulatory roles in the motility and virulence of Xanthomonas campestris. MOLECULAR PLANT PATHOLOGY 2022; 23:355-369. [PMID: 34837306 PMCID: PMC8828458 DOI: 10.1111/mpp.13164] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/22/2021] [Revised: 10/26/2021] [Accepted: 10/26/2021] [Indexed: 05/08/2023]
Abstract
Xanthomonas campestris pv. campestris (Xcc) can cause black rot in cruciferous plants worldwide. Two-component systems (TCSs) are key for bacterial adaptation to various environments, including hosts. VemR is a TCS response regulator and crucial for Xcc motility and virulence. Here, we report that RavA is the cognate histidine kinase (HK) of VemR and elucidate the signalling pathway by which VemR regulates Xcc motility and virulence. Genetic analysis showed that VemR is epistatic to RavA. Using bacterial two-hybrid experiments and pull-down and phosphorylation assays, we found that RavA can interact with and phosphorylate VemR, suggesting that RavA is the cognate HK of VemR. In addition, we found that RpoN2 and FleQ are epistatic to VemR in regulating bacterial motility and virulence. In vivo and in vitro experiments demonstrated that VemR interacts with FleQ but not with RpoN2. RavA/VemR regulates the expression of the flagellin-encoding gene fliC by activating the transcription of the rpoN2-vemR-fleQ and flhF-fleN-fliA operons. In summary, our data show that the RavA/VemR TCS regulates FleQ activity and thus influences the expression of motility-related genes, thereby affecting Xcc motility and virulence. The identification of this novel signalling pathway will deepen our understanding of Xcc-plant interactions.
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Affiliation(s)
- Maojuan Lin
- Hainan Key Laboratory for Sustainable Utilization of Tropical Bioresources, College of Tropical CropsHainan UniversityHaikouHainanChina
| | - Kejian Wu
- Hainan Key Laboratory for Sustainable Utilization of Tropical Bioresources, College of Tropical CropsHainan UniversityHaikouHainanChina
| | - Zhaohong Zhan
- Hainan Key Laboratory for Sustainable Utilization of Tropical Bioresources, College of Tropical CropsHainan UniversityHaikouHainanChina
| | - Duo Mi
- Hainan Key Laboratory for Sustainable Utilization of Tropical Bioresources, College of Tropical CropsHainan UniversityHaikouHainanChina
| | - Yingying Xia
- Hainan Key Laboratory for Sustainable Utilization of Tropical Bioresources, College of Tropical CropsHainan UniversityHaikouHainanChina
| | - Xiaolei Niu
- Hainan Key Laboratory for Sustainable Utilization of Tropical Bioresources, College of Tropical CropsHainan UniversityHaikouHainanChina
| | - Shipeng Feng
- Hainan Key Laboratory for Sustainable Utilization of Tropical Bioresources, College of Tropical CropsHainan UniversityHaikouHainanChina
| | - Yinhua Chen
- Hainan Key Laboratory for Sustainable Utilization of Tropical Bioresources, College of Tropical CropsHainan UniversityHaikouHainanChina
| | - Chaozu He
- Hainan Key Laboratory for Sustainable Utilization of Tropical Bioresources, College of Tropical CropsHainan UniversityHaikouHainanChina
| | - Jun Tao
- Hainan Key Laboratory for Sustainable Utilization of Tropical Bioresources, College of Tropical CropsHainan UniversityHaikouHainanChina
| | - Chunxia Li
- Hainan Key Laboratory for Sustainable Utilization of Tropical Bioresources, College of Tropical CropsHainan UniversityHaikouHainanChina
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21
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Pandey SS, Chatterjee S. Insights into the Cell-to-Cell Signaling and Iron Homeostasis in Xanthomonas Virulence and Lifestyle. PHYTOPATHOLOGY 2022; 112:209-218. [PMID: 34289715 DOI: 10.1094/phyto-11-20-0513-rvw] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
The Xanthomonas group of phytopathogens causes economically important diseases that lead to severe yield loss in major crops. Some Xanthomonas species are known to have an epiphytic and in planta lifestyle that is coordinated by several virulence-associated functions, cell-to-cell signaling (using diffusible signaling factor [DSF]), and environmental conditions, including iron availability. In this review, we described the role of cell-to-cell signaling by the DSF molecule and iron in the regulation of virulence-associated functions. Although DSF and iron are involved in the regulation of several virulence-associated functions, members of the Xanthomonas group of plant pathogens exhibit atypical patterns of regulation. Atypical patterns contribute to the adaptation to different lifestyles. Studies on DSF and iron biology indicate that virulence-associated functions can be regulated in completely contrasting fashions by the same signaling system in closely related xanthomonads.
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Affiliation(s)
- Sheo Shankar Pandey
- Citrus Research and Education Center, Institute of Food and Agricultural Sciences, University of Florida, Lake Alfred, FL 33850, U.S.A
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Wang Q, Guo J, An L, Bao Y. Integration of DSF and Temperature Signals for RpfC/RpfG Two-Component System Modulating Protease Production in Stenotrophomonas maltophilia FF11. Curr Microbiol 2022; 79:54. [PMID: 34982238 DOI: 10.1007/s00284-021-02731-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2021] [Accepted: 11/29/2021] [Indexed: 11/26/2022]
Abstract
Two-component signal system (TCS) is the predominant bacterial sense-and-response machinery. RpfC/RpfG TCS involved in quorum sensing molecule Diffuse Signal Factor (DSF) signal perception and transduction was well studied in many bacteria. However, whether other environmental factors participating in the signal perception and transduction of RpfC/RpfG was still unclear. Here, we showed that RpfC/RpfG could integrate temperature and DSF signal partially controlling the production of the temperature-dependent protease (SmtP) in S. maltophilia FF11, a strain isolated from frozen Antarctic krill, exhibited spoilage potential due to secret more protease at low temperatures involving in protein degradation. qRT-PCR analysis revealed rpf system mediating approximately 60% transcription activity of Clp, a critical transcription factor linking with LotS/LotR, consisting a signal network controlling completely the SmtP production in previous study. Protease production was partially reduced in rpfF (coding DSF synthetase) mutant strains at 15 °C or 25 °C, not be increased through addition DSF or overexpression RpfF in WT at 37 °C, indicating that DSF was effective for protease production only at low temperatures in S. maltophilia. Additionally, biochemical analysis revealed the enzymatic activity of RpfG from strain FF11 cultured at 37 °C or DSF-deficient strains grown at 25 °C was significantly reduced compared to that of RpfG from strain FF11 cultured at 25 °C. These findings outline an interplay mechanism that allows S. maltophilia to integrate quorum sensing and temperature cues controlling protease production, and imply a potential relationship between two distinct systems of RpfC/RpfG and LotS/LotR.
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Affiliation(s)
- Qingling Wang
- Shaanxi Natural Carbohydrate Resource Engineering Research Center, College of Food Science and Technology, Northwest University, Xi'an, 710069, China.
- School of Life Science and Biotechnology, Dalian University of Technology, Dalian, 116024, China.
| | - Jianli Guo
- School of Life Science and Biotechnology, Dalian University of Technology, Dalian, 116024, China
| | - Lijia An
- School of Life Science and Biotechnology, Dalian University of Technology, Dalian, 116024, China
| | - Yongming Bao
- School of Life Science and Biotechnology, Dalian University of Technology, Dalian, 116024, China.
- School of Food and Environment Science and Technology, Dalian University of Technology, Panjin, 124221, China.
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Lv M, Chen Y, Hu M, Yu Q, Duan C, Ye S, Ling J, Zhou J, Zhou X, Zhang L. OhrR is a central transcriptional regulator of virulence in Dickeya zeae. MOLECULAR PLANT PATHOLOGY 2022; 23:45-59. [PMID: 34693617 PMCID: PMC8659590 DOI: 10.1111/mpp.13141] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/17/2021] [Revised: 08/20/2021] [Accepted: 09/01/2021] [Indexed: 06/12/2023]
Abstract
Dickeya zeae is the causal agent of rice foot rot disease. The pathogen is known to rely on a range of virulence factors, including phytotoxin zeamines, extracellular enzymes, cell motility, and biofilm, which collectively contribute to the establishment of infections. Phytotoxin zeamines play a critical role in bacterial virulence; signalling pathways and regulatory mechanisms that govern bacterial virulence remain unclear. In this study, we identified a transcriptional regulator OhrR (organic hydroperoxide reductase regulator) that is involved in the regulation of zeamine production in D. zeae EC1. The OhrR null mutant was significantly attenuated in its virulence against rice seed, potato tubers and radish roots. Phenotype analysis showed that OhrR was also involved in the regulation of other virulence traits, including the production of extracellular cellulase, biofilm formation, and swimming/swarming motility. DNA electrophoretic mobility shift assay showed that OhrR directly regulates the transcription of key virulence genes and genes encoding bis-(3'-5')-cyclic dimeric guanosine monophosphate synthetases. Furthermore, OhrR positively regulates the transcription of regulatory genes slyA and fis through binding to their promoter regions. Our findings identify a key regulator of the virulence of D. zeae and add new insights into the complex regulatory network that modulates the physiology and virulence of D. zeae.
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Affiliation(s)
- Mingfa Lv
- Integrative Microbiology Research CentreSouth China Agricultural UniversityGuangzhouChina
- Guangdong Province Key Laboratory of Microbial Signals and Disease ControlSouth China Agricultural UniversityGuangzhouChina
- Guangdong Laboratory for Lingnan Modern AgricultureSouth China Agricultural UniversityGuangzhouChina
| | - Yufan Chen
- Integrative Microbiology Research CentreSouth China Agricultural UniversityGuangzhouChina
- Guangdong Province Key Laboratory of Microbial Signals and Disease ControlSouth China Agricultural UniversityGuangzhouChina
- Guangdong Laboratory for Lingnan Modern AgricultureSouth China Agricultural UniversityGuangzhouChina
| | - Ming Hu
- Integrative Microbiology Research CentreSouth China Agricultural UniversityGuangzhouChina
- Guangdong Province Key Laboratory of Microbial Signals and Disease ControlSouth China Agricultural UniversityGuangzhouChina
- Guangdong Laboratory for Lingnan Modern AgricultureSouth China Agricultural UniversityGuangzhouChina
| | - Qinglin Yu
- Integrative Microbiology Research CentreSouth China Agricultural UniversityGuangzhouChina
- Guangdong Province Key Laboratory of Microbial Signals and Disease ControlSouth China Agricultural UniversityGuangzhouChina
- Guangdong Laboratory for Lingnan Modern AgricultureSouth China Agricultural UniversityGuangzhouChina
| | - Cheng Duan
- Integrative Microbiology Research CentreSouth China Agricultural UniversityGuangzhouChina
- Guangdong Province Key Laboratory of Microbial Signals and Disease ControlSouth China Agricultural UniversityGuangzhouChina
- Guangdong Laboratory for Lingnan Modern AgricultureSouth China Agricultural UniversityGuangzhouChina
| | - Sixuan Ye
- Integrative Microbiology Research CentreSouth China Agricultural UniversityGuangzhouChina
- Guangdong Province Key Laboratory of Microbial Signals and Disease ControlSouth China Agricultural UniversityGuangzhouChina
- Guangdong Laboratory for Lingnan Modern AgricultureSouth China Agricultural UniversityGuangzhouChina
| | - Jinfeng Ling
- Guangdong Provincial Key Laboratory of High Technology for Plant ProtectionResearch Institute of Plant ProtectionGuangdong Academy of Agricultural SciencesGuangzhouChina
| | - Jianuan Zhou
- Integrative Microbiology Research CentreSouth China Agricultural UniversityGuangzhouChina
- Guangdong Province Key Laboratory of Microbial Signals and Disease ControlSouth China Agricultural UniversityGuangzhouChina
- Guangdong Laboratory for Lingnan Modern AgricultureSouth China Agricultural UniversityGuangzhouChina
| | - Xiaofan Zhou
- Integrative Microbiology Research CentreSouth China Agricultural UniversityGuangzhouChina
- Guangdong Province Key Laboratory of Microbial Signals and Disease ControlSouth China Agricultural UniversityGuangzhouChina
- Guangdong Laboratory for Lingnan Modern AgricultureSouth China Agricultural UniversityGuangzhouChina
| | - Lianhui Zhang
- Integrative Microbiology Research CentreSouth China Agricultural UniversityGuangzhouChina
- Guangdong Province Key Laboratory of Microbial Signals and Disease ControlSouth China Agricultural UniversityGuangzhouChina
- Guangdong Laboratory for Lingnan Modern AgricultureSouth China Agricultural UniversityGuangzhouChina
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24
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The predatory soil bacterium Lysobacter reprograms quorum sensing system to regulate antifungal antibiotic production in a cyclic-di-GMP-independent manner. Commun Biol 2021; 4:1131. [PMID: 34561536 PMCID: PMC8463545 DOI: 10.1038/s42003-021-02660-7] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2021] [Accepted: 09/10/2021] [Indexed: 11/17/2022] Open
Abstract
Soil bacteria often harbour various toxins to against eukaryotic or prokaryotic. Diffusible signal factors (DSFs) represent a unique group of quorum sensing (QS) chemicals that modulate interspecies competition in bacteria that do not produce antibiotic-like molecules. However, the molecular mechanism by which DSF-mediated QS systems regulate antibiotic production for interspecies competition remains largely unknown in soil biocontrol bacteria. In this study, we find that the necessary QS system component protein RpfG from Lysobacter, in addition to being a cyclic dimeric GMP (c-di-GMP) phosphodiesterase (PDE), regulates the biosynthesis of an antifungal factor (heat-stable antifungal factor, HSAF), which does not appear to depend on the enzymatic activity. Interestingly, we show that RpfG interacts with three hybrid two-component system (HyTCS) proteins, HtsH1, HtsH2, and HtsH3, to regulate HSAF production in Lysobacter. In vitro studies show that each of these proteins interacted with RpfG, which reduced the PDE activity of RpfG. Finally, we show that the cytoplasmic proportions of these proteins depended on their phosphorylation activity and binding to the promoter controlling the genes implicated in HSAF synthesis. These findings reveal a previously uncharacterized mechanism of DSF signalling in antibiotic production in soil bacteria. Li et al shows that the quorum sensing system component protein RpfG from Lysobacter, in addition to being a cyclic dimeric GMP (c-di-GMP) phosphodiesterase, also regulates the biosynthesis of an antifungal factor. They show that RpfG regulates the production of HSAF through a direct interaction with three hybrid two component system (HyTCS) proteins, providing insights into the antifungal defence in soil bacteria.
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25
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Wan X, Yang J, Ahmed W, Liu Q, Wang Y, Wei L, Ji G. Functional analysis of pde gene and its role in the pathogenesis of Xanthomonas oryzae pv. oryzicola. INFECTION GENETICS AND EVOLUTION 2021; 94:105008. [PMID: 34284137 DOI: 10.1016/j.meegid.2021.105008] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/08/2021] [Revised: 05/16/2021] [Accepted: 07/15/2021] [Indexed: 11/16/2022]
Abstract
Bacterial leaf streak caused by Xanthomonas oryzae pv. oryzicola (Xoc) is a devastating disease of rice worldwide, including China. The second messenger c-di-GMP plays an important role in the transduction of intercellular signals. However, little is known about the function of EAL domain protein in c-di-GMP that regulates the virulence in Xoc. In this study, the function of EAL domain protein encoded by pde (FE36_09715) gene in the regulation of c-di-GMP was investigated. Results of this study, showed that the deletion of pde gene led to a significant reduction in the virulence of Xoc and was positively related to the reduction of exopolysaccharides production, biofilm formation, and flagellar motility. However, these significantly impaired properties from the ∆pde mutant strain were partially recovered in the complementary strain. In addition, the deletion of pde gene in Xoc strain YM15 had no visible effect on the colony morphology, amylase, and protease activities of Xoc. It is concluded that, as a regulator for the c-di-GMP level, the pde gene plays an important role in partial biological processes in Xoc and is essential for its virulence.
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Affiliation(s)
- Xiaoyan Wan
- Key Laboratory of Agriculture Biodiversity for Plant Disease Management Under the Ministry of Education, Yunnan Agricultural University, Kunming 650201, China
| | - Jun Yang
- Academy of Science and Technology, Chuxiong Normal University, Chuxiong 675000, China
| | - Waqar Ahmed
- Key Laboratory of Agriculture Biodiversity for Plant Disease Management Under the Ministry of Education, Yunnan Agricultural University, Kunming 650201, China
| | - Qi Liu
- Key Laboratory of Agriculture Biodiversity for Plant Disease Management Under the Ministry of Education, Yunnan Agricultural University, Kunming 650201, China
| | - Yanfang Wang
- Key Laboratory of Agriculture Biodiversity for Plant Disease Management Under the Ministry of Education, Yunnan Agricultural University, Kunming 650201, China
| | - Lanfang Wei
- Key Laboratory of Agriculture Biodiversity for Plant Disease Management Under the Ministry of Education, Yunnan Agricultural University, Kunming 650201, China
| | - Guanghai Ji
- Key Laboratory of Agriculture Biodiversity for Plant Disease Management Under the Ministry of Education, Yunnan Agricultural University, Kunming 650201, China.
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26
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Kakkar A, Verma RK, Samal B, Chatterjee S. Interplay between the cyclic di-GMP network and the cell-cell signalling components coordinates virulence-associated functions in Xanthomonas oryzae pv. oryzae. Environ Microbiol 2021; 23:5433-5462. [PMID: 34240791 DOI: 10.1111/1462-2920.15664] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2021] [Accepted: 07/06/2021] [Indexed: 11/29/2022]
Abstract
Xanthomonas oryzae pv. oryzae (Xoo) causes a serious disease of rice known as bacterial leaf blight. Several virulence-associated functions have been characterized in Xoo. However, the role of important second messenger c-di-GMP signalling in the regulation of virulence-associated functions still remains elusive in this phytopathogen. In this study we have performed an investigation of 13 c-di-GMP modulating deletion mutants to understand their contribution in Xoo virulence and lifestyle transition. We show that four Xoo proteins, Xoo2331, Xoo2563, Xoo2860 and Xoo2616, are involved in fine-tuning the in vivo c-di-GMP abundance and also play a role in the regulation of virulence-associated functions. We have further established the importance of the GGDEF domain of Xoo2563, a previously characterized c-di-GMP phosphodiesterase, in the virulence-associated functions of Xoo. Interestingly the strain harbouring the GGDEF domain deletion (ΔXoo2563GGDEF ) exhibited EPS deficiency and hypersensitivity to streptonigrin, indicative of altered iron metabolism. This is in contrast to the phenotype exhibited by an EAL overexpression strain wherein, the ΔXoo2563GGDEF exhibited other phenotypes, similar to the strain overexpressing the EAL domain. Taken together, our results indicate a complex interplay of c-di-GMP signalling with the cell-cell signalling to coordinate virulence-associated function in Xoo.
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Affiliation(s)
- Akanksha Kakkar
- Centre for DNA Fingerprinting and Diagnostics, Uppal, Hyderabad, 500039, India.,Graduate Studies, Manipal Academy of Higher Education, Mangalore, Karnataka, 576104, India
| | - Raj Kumar Verma
- Centre for DNA Fingerprinting and Diagnostics, Uppal, Hyderabad, 500039, India.,Graduate Studies, Manipal Academy of Higher Education, Mangalore, Karnataka, 576104, India
| | - Biswajit Samal
- Centre for DNA Fingerprinting and Diagnostics, Uppal, Hyderabad, 500039, India.,Graduate Studies, Manipal Academy of Higher Education, Mangalore, Karnataka, 576104, India
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27
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Lin Y, Liao YY, Huang RX, Li AZ, An SQ, Tang JL, Tang DJ. Extracellular Amylase Is Required for Full Virulence and Regulated by the Global Posttranscriptional Regulator RsmA in Xanthomonas campestris Pathovar campestris. PHYTOPATHOLOGY 2021; 111:1104-1113. [PMID: 33245253 DOI: 10.1094/phyto-08-20-0372-r] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
As with many phytopathogenic bacteria, the virulence of Xanthomonas campestris pv. campestris, the causal agent of black rot disease in cruciferous plants, relies on secretion of a suite of extracellular enzymes that includes cellulase (endoglucanase), pectinase, protease, and amylase. Although the role in virulence of a number of these enzymes has been assessed, the contribution of amylase to X. campestris pv. campestris virulence has yet to be established. In this work, we investigated both the role of extracellular amylase in X. campestris pv. campestris virulence and the control of its expression. Deletion of XC3487 (here renamed amyAXcc), a putative amylase-encoding gene from the genome of X. campestris pv. campestris strain 8004, resulted in a complete loss of extracellular amylase activity and significant reduction in virulence. The extracellular amylase activity and virulence of the amyAXcc mutant could be restored to the wild-type level by expressing amyAXcc in trans. These results demonstrated that amyAXcc is responsible for the extracellular amylase activity of X. campestris pv. campestris and indicated that extracellular amylase plays an important role in X. campestris pv. campestris virulence. We also found that the expression of amyAXcc is strongly induced by starch and requires activation by the global posttranscriptional regulator RsmA. RsmA binds specifically to the 5'-untranslated region of amyAXcc transcripts, suggesting that RsmA regulates amyAXcc directly at the posttranscriptional level. Unexpectedly, in addition to posttranscriptional regulation, the use of a transcriptional reporter demonstrated that RsmA also regulates amyAXcc expression at the transcriptional level, possibly by an indirect mechanism.
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Affiliation(s)
- Yan Lin
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-bioresources, and College of Life Science and Technology, Guangxi University, Nanning, Guangxi 530004, China
| | - Yong-Yan Liao
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-bioresources, and College of Life Science and Technology, Guangxi University, Nanning, Guangxi 530004, China
| | - Ru-Xia Huang
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-bioresources, and College of Life Science and Technology, Guangxi University, Nanning, Guangxi 530004, China
| | - Ai-Zhou Li
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-bioresources, and College of Life Science and Technology, Guangxi University, Nanning, Guangxi 530004, China
| | - Shi-Qi An
- National Biofilms Innovation Centre, Biological Sciences, University of Southampton, Southampton SO17 1BJ, United Kingdom
| | - Ji-Liang Tang
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-bioresources, and College of Life Science and Technology, Guangxi University, Nanning, Guangxi 530004, China
| | - Dong-Jie Tang
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-bioresources, and College of Life Science and Technology, Guangxi University, Nanning, Guangxi 530004, China
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28
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Xu K, Lin L, Shen D, Chou SH, Qian G. Clp is a "busy" transcription factor in the bacterial warrior, Lysobacter enzymogenes. Comput Struct Biotechnol J 2021; 19:3564-3572. [PMID: 34257836 PMCID: PMC8246147 DOI: 10.1016/j.csbj.2021.06.020] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2021] [Revised: 06/13/2021] [Accepted: 06/13/2021] [Indexed: 02/06/2023] Open
Abstract
Cyclic AMP receptor protein (CRP) is a well-characterized group of global transcription factors in bacteria. They are known to regulate numerous cellular processes by binding DNA and/or cAMP (a ligand called bacterial second messenger) to control target gene expression. Gram-negative Lysobacter enzymogenes is a soilborne, plant-beneficial bacterium without flagella that can fight against filamentous fungi and oomycete. Driven by the type IV pilus (T4P) system, this bacterium moves to nearby pathogens and uses a “mobile-attack” antifungal strategy to kill them via heat-stable antifungal factor (HSAF) and abundant lyases. This strategy is controlled by a unique “busy” transcription factor Clp, which is a CRP-like protein that is inactivated by binding of c-di-GMP, another ubiquitous second messenger of bacteria. In this review, we summarize the current progress in how Clp initiates a “mobile-attack” strategy through a series of previously uncharacterized mechanisms, including binding to DNA in a unique pattern, directly interacting with or responding to various small molecules, and interacting specifically with proteins adopting distinct structure. Together, these characteristics highlight the multifunctional roles of Clp in L. enzymogenes, a powerful bacterial warrior against fungal pathogens.
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Affiliation(s)
- Kangwen Xu
- College of Plant Protection, Laboratory of Plant Immunity, Key Laboratory of Integrated Management of Crop Diseases and Pests, Nanjing Agricultural University, No.1 Weigang, Nanjing, Jiangsu 210095, PR China
| | - Long Lin
- College of Plant Protection, Laboratory of Plant Immunity, Key Laboratory of Integrated Management of Crop Diseases and Pests, Nanjing Agricultural University, No.1 Weigang, Nanjing, Jiangsu 210095, PR China
| | - Danyu Shen
- College of Plant Protection, Laboratory of Plant Immunity, Key Laboratory of Integrated Management of Crop Diseases and Pests, Nanjing Agricultural University, No.1 Weigang, Nanjing, Jiangsu 210095, PR China
| | - Shan-Ho Chou
- Institute of Biochemistry, and NCHU Agricultural Biotechnology Center, National Chung Hsing University, Taichung, Taiwan, ROC
| | - Guoliang Qian
- College of Plant Protection, Laboratory of Plant Immunity, Key Laboratory of Integrated Management of Crop Diseases and Pests, Nanjing Agricultural University, No.1 Weigang, Nanjing, Jiangsu 210095, PR China
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29
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Zhang Q, Xing C, Kong X, Wang C, Chen X. ChIP-seq Analysis of the Global Regulator Vfr Reveals Novel Insights Into the Biocontrol Agent Pseudomonas protegens FD6. Front Microbiol 2021; 12:667637. [PMID: 34054776 PMCID: PMC8160232 DOI: 10.3389/fmicb.2021.667637] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2021] [Accepted: 04/19/2021] [Indexed: 11/13/2022] Open
Abstract
Many Pseudomonas protegens strains produce the antibiotics pyoluteorin (PLT) and 2,4-diacetylphloroglucinol (2,4-DAPG), both of which have antimicrobial properties. The biosynthesis of these metabolites is typically controlled by multiple regulatory factors. Virulence factor regulator (Vfr) is a multifunctional DNA-binding regulator that modulates 2,4-DAPG biosynthesis in P. protegens FD6. However, the mechanism by which Vfr regulates this process remains unclear. In the present study, chromatin immunoprecipitation of FLAG-tagged Vfr and nucleotide sequencing analysis were used to identify 847 putative Vfr binding sites in P. protegens FD6. The consensus P. protegens Vfr binding site predicted from nucleotide sequence alignment is TCACA. The qPCR data showed that Vfr positively regulates the expression of phlF and phlG, and the expression of these genes was characterized in detail. The purified recombinant Vfr bound to an approximately 240-bp fragment within the phlF and phlG upstream regions that harbor putative Vfr consensus sequences. Using electrophoretic mobility shift assays, we localized Vfr binding to a 25-bp fragment that contains part of the Vfr binding region. Vfr binding was eliminated by mutating the TACG and CACA sequences in phlF and phlG, respectively. Taken together, our results show that Vfr directly regulates the expression of the 2,4-DAPG operon by binding to the upstream regions of both the phlF and phlG genes. However, unlike other Vfr-targeted genes, Vfr binding to P. protegens FD6 does not require an intact binding consensus motif. Furthermore, we demonstrated that vfr expression is autoregulated in this bacterium. These results provide novel insights into the regulatory role of Vfr in the biocontrol agent P. protegens.
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Affiliation(s)
- Qingxia Zhang
- College of Horticulture and Plant Protection, Yangzhou University, Yangzhou, China.,Joint International Research Laboratory of Agriculture and Agri-Product Safety, The Ministry of Education of China, Yangzhou University, Yangzhou, China
| | - Chenglin Xing
- College of Horticulture and Plant Protection, Yangzhou University, Yangzhou, China
| | - Xiangwei Kong
- College of Horticulture and Plant Protection, Yangzhou University, Yangzhou, China
| | - Cheng Wang
- College of Horticulture and Plant Protection, Yangzhou University, Yangzhou, China
| | - Xijun Chen
- College of Horticulture and Plant Protection, Yangzhou University, Yangzhou, China
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30
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Abstract
Xanthomonas is a notorious plant pathogen causing serious diseases in hundreds of plant hosts. Xanthomonas species are equipped with an array of signal transduction systems that regulate gene expression to survive in various harsh environments and successfully infect hosts. Although certain pathogenicity-associated regulators have been functionally characterized, signal transduction systems always function as a regulatory network which remains to be elucidated in Xanthomonas. This study used a systematic approach to characterize all identified pathogenicity-associated regulators in Xanthomonas oryzae pv. oryzae (Xoo), including a transcriptional regulator with unknown function, and their interactive regulatory network. RNA sequencing was used in elucidating the patterns of the 10 pathogenicity-associated regulators identified. Results revealed that each pathogenicity-associated regulator has cross talk with others and all these regulators function as a regulatory network, with VemR and PXO_RS20790 being the master pathogenicity-associated regulators and HrpX being the final executant. Moreover, regulome analysis showed that numerous genes other than genes in pathogenicity islands are finely regulated within the regulatory network. Given that most of the pathogenicity-associated regulators are conserved in Xanthomonadales, our findings suggest a global network of gene regulation in this evolutionarily conserved pathogen. In conclusion, our study provides essential basic information about the regulatory network in Xoo, suggesting that this complicated regulatory network is one of the reasons for the robustness and fitness of Xanthomonas spp. IMPORTANCE The host plant infection process of pathogenic bacteria is a coordinating cellular behavior, which requires dynamic regulation at several levels in response to variations in host plants or fluctuations in the external environment. As one of the most important genera of plant-pathogenic bacteria, Xanthomonas has been studied as a model. Although certain pathogenicity-associated regulators have been functionally characterized, interactions among them remain to be elucidated. This study systematically characterized pathogenicity-associated regulators in Xoo and revealed that cross talk exists among pathogenicity-associated regulators and function as a regulatory network in which a hierarchy exists among the regulators. Our study elucidated the landscape of the pathogenicity-associated regulatory network in Xanthomonas, promoting understanding of the infection process of pathogenic bacteria.
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31
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Guo Y, Zhao Y, Tang X, Na T, Pan J, Zhao H, Liu S. Deciphering bacterial social traits via diffusible signal factor (DSF) -mediated public goods in an anammox community. WATER RESEARCH 2021; 191:116802. [PMID: 33433336 DOI: 10.1016/j.watres.2020.116802] [Citation(s) in RCA: 26] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/23/2020] [Revised: 12/04/2020] [Accepted: 12/30/2020] [Indexed: 06/12/2023]
Abstract
Both the benefits of bacterial quorum sensing (QS) and cross-feeding for bio-reactor performance in wastewater treatment have been recently reported. As the social traits of microbial communities, how bacterial QS regulating bacterial trade-off by cross-feeding remains unclear. Here, we find diffusion signal factor (DSF), a kind of QS molecules, can bridge bacterial interactions through regulating public goods (extracellular polymeric substances (EPS), amino acids) for metabolic cross-feedings. It showed that exogenous DSF-addition leads to change of public goods level and community structure dynamics in the anammox consortia. Approaches involving meta-omics clarified that anammox and a Lautropia-affiliated species in the phylum Proteobacteria can supply costly public goods for DSF-Secretor species via secondary messenger c-di-GMP regulator (Clp) after sensing DSF. Meanwhile, DSF-Secretor species help anammox bacteria scavenge extracellular detritus, which creates a more suitable environment for the anammox species, enhances the anammox activity, and improves the nitrogen removal rate of anammox reactor. The trade-off induces discrepant metabolic loads of different microbial clusters, which were responsible for the community succession. It illustrated the potential to artificially alleviate metabolic loads for certain bacteria. Deciphering microbial interactions via QS not only provides insights for understanding the social behavior of microbial community, but also creates new thought for enhancing treatment performance through regulating bacterial social traits via quorum sensing-mediated public goods.
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Affiliation(s)
- Yongzhao Guo
- College of Environmental Sciences and Engineering, Peking University, Beijing 100871, China; State Environmental Protection Key Laboratory of All Material Fluxes in River Ecosystems, Beijing, 100871, China
| | - Yunpeng Zhao
- College of Environmental Sciences and Engineering, Peking University, Beijing 100871, China; State Environmental Protection Key Laboratory of All Material Fluxes in River Ecosystems, Beijing, 100871, China
| | - Xi Tang
- College of Environmental Sciences and Engineering, Peking University, Beijing 100871, China; State Environmental Protection Key Laboratory of All Material Fluxes in River Ecosystems, Beijing, 100871, China
| | - Tianxing Na
- College of Environmental Sciences and Engineering, Peking University, Beijing 100871, China
| | - Juejun Pan
- College of Environmental Sciences and Engineering, Peking University, Beijing 100871, China; State Environmental Protection Key Laboratory of All Material Fluxes in River Ecosystems, Beijing, 100871, China
| | - Huazhang Zhao
- College of Environmental Sciences and Engineering, Peking University, Beijing 100871, China; State Environmental Protection Key Laboratory of All Material Fluxes in River Ecosystems, Beijing, 100871, China
| | - Sitong Liu
- College of Environmental Sciences and Engineering, Peking University, Beijing 100871, China; International Joint Laboratory for Regional Pollution Control, Ministry of Education of China, Beijing 100871, China.
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The HrpG/HrpX Regulon of Xanthomonads-An Insight to the Complexity of Regulation of Virulence Traits in Phytopathogenic Bacteria. Microorganisms 2021; 9:microorganisms9010187. [PMID: 33467109 PMCID: PMC7831014 DOI: 10.3390/microorganisms9010187] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2020] [Revised: 01/11/2021] [Accepted: 01/13/2021] [Indexed: 12/05/2022] Open
Abstract
Bacteria of the genus Xanthomonas cause a wide variety of economically important diseases in most crops. The virulence of the majority of Xanthomonas spp. is dependent on secretion and translocation of effectors by the type 3 secretion system (T3SS) that is controlled by two master transcriptional regulators HrpG and HrpX. Since their discovery in the 1990s, the two regulators were the focal point of many studies aiming to decipher the regulatory network that controls pathogenicity in Xanthomonas bacteria. HrpG controls the expression of HrpX, which subsequently controls the expression of T3SS apparatus genes and effectors. The HrpG/HrpX regulon is activated in planta and subjected to tight metabolic and genetic regulation. In this review, we cover the advances made in understanding the regulatory networks that control and are controlled by the HrpG/HrpX regulon and their conservation between different Xanthomonas spp.
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Secrete or perish: The role of secretion systems in Xanthomonas biology. Comput Struct Biotechnol J 2020; 19:279-302. [PMID: 33425257 PMCID: PMC7777525 DOI: 10.1016/j.csbj.2020.12.020] [Citation(s) in RCA: 31] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2020] [Revised: 12/13/2020] [Accepted: 12/13/2020] [Indexed: 12/22/2022] Open
Abstract
Bacteria of the Xanthomonas genus are mainly phytopathogens of a large variety of crops of economic importance worldwide. Xanthomonas spp. rely on an arsenal of protein effectors, toxins and adhesins to adapt to the environment, compete with other microorganisms and colonize plant hosts, often causing disease. These protein effectors are mainly delivered to their targets by the action of bacterial secretion systems, dedicated multiprotein complexes that translocate proteins to the extracellular environment or directly into eukaryotic and prokaryotic cells. Type I to type VI secretion systems have been identified in Xanthomonas genomes. Recent studies have unravelled the diverse roles played by the distinct types of secretion systems in adaptation and virulence in xanthomonads, unveiling new aspects of their biology. In addition, genome sequence information from a wide range of Xanthomonas species and pathovars have become available recently, uncovering a heterogeneous distribution of the distinct families of secretion systems within the genus. In this review, we describe the architecture and mode of action of bacterial type I to type VI secretion systems and the distribution and functions associated with these important nanoweapons within the Xanthomonas genus.
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The Roles of Microbial Cell-Cell Chemical Communication Systems in the Modulation of Antimicrobial Resistance. Antibiotics (Basel) 2020; 9:antibiotics9110779. [PMID: 33171916 PMCID: PMC7694446 DOI: 10.3390/antibiotics9110779] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2020] [Revised: 11/02/2020] [Accepted: 11/04/2020] [Indexed: 01/25/2023] Open
Abstract
Rapid emergence of antimicrobial resistance (AMR) has become a critical challenge worldwide. It is of great importance to understand how AMR is modulated genetically in order to explore new antimicrobial strategies. Recent studies have unveiled that microbial communication systems, which are known to play key roles in regulation of bacterial virulence, are also associated with the formation and regulation of AMR. These microbial cell-to-cell chemical communication systems, including quorum sensing (QS) and pathogen-host communication mechanisms, rely on detection and response of various chemical signal molecules, which are generated either by the microbe itself or host cells, to activate the expression of virulence and AMR genes. This article summarizes the generic signaling mechanisms of representative QS and pathogen-host communications systems, reviews the current knowledge regarding the roles of these chemical communication systems in regulation of AMR, and describes the strategies developed over the years for blocking bacterial chemical communication systems in disease control. The research progress in this field suggests that the bacterial cell-cell communication systems are a promising target not only for disease control but also for curbing the problem of microbial drug resistance.
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Botero D, Monk J, Rodríguez Cubillos MJ, Rodríguez Cubillos A, Restrepo M, Bernal-Galeano V, Reyes A, González Barrios A, Palsson BØ, Restrepo S, Bernal A. Genome-Scale Metabolic Model of Xanthomonas phaseoli pv. manihotis: An Approach to Elucidate Pathogenicity at the Metabolic Level. Front Genet 2020; 11:837. [PMID: 32849823 PMCID: PMC7432306 DOI: 10.3389/fgene.2020.00837] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2019] [Accepted: 07/10/2020] [Indexed: 01/05/2023] Open
Abstract
Xanthomonas phaseoli pv. manihotis (Xpm) is the causal agent of cassava bacterial blight, the most important bacterial disease in this crop. There is a paucity of knowledge about the metabolism of Xanthomonas and its relevance in the pathogenic process, with the exception of the elucidation of the xanthan biosynthesis route. Here we report the reconstruction of the genome-scale model of Xpm metabolism and the insights it provides into plant-pathogen interactions. The model, iXpm1556, displayed 1,556 reactions, 1,527 compounds, and 890 genes. Metabolic maps of central amino acid and carbohydrate metabolism, as well as xanthan biosynthesis of Xpm, were reconstructed using Escher (https://escher.github.io/) to guide the curation process and for further analyses. The model was constrained using the RNA-seq data of a mutant of Xpm for quorum sensing (QS), and these data were used to construct context-specific models (CSMs) of the metabolism of the two strains (wild type and QS mutant). The CSMs and flux balance analysis were used to get insights into pathogenicity, xanthan biosynthesis, and QS mechanisms. Between the CSMs, 653 reactions were shared; unique reactions belong to purine, pyrimidine, and amino acid metabolism. Alternative objective functions were used to demonstrate a trade-off between xanthan biosynthesis and growth and the re-allocation of resources in the process of biosynthesis. Important features altered by QS included carbohydrate metabolism, NAD(P)+ balance, and fatty acid elongation. In this work, we modeled the xanthan biosynthesis and the QS process and their impact on the metabolism of the bacterium. This model will be useful for researchers studying host-pathogen interactions and will provide insights into the mechanisms of infection used by this and other Xanthomonas species.
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Affiliation(s)
- David Botero
- Laboratory of Mycology and Plant Pathology (LAMFU), Department of Chemical and Food Engineering, Universidad de Los Andes, Bogotá, Colombia
- Grupo de Diseño de Productos y Procesos (GDPP), Department of Chemical and Food Engineering, Universidad de Los Andes, Bogotá, Colombia
- Max Planck Tandem Group in Computational Biology, Universidad de Los Andes, Bogotá, Colombia
- Grupo de Biología Computacional y Ecología Microbiana, Department of Biological Sciences, Universidad de Los Andes, Bogotá, Colombia
| | - Jonathan Monk
- Systems Biology Research Group, Department of Bioengineering, University of California, San Diego, San Diego, CA, United States
| | - María Juliana Rodríguez Cubillos
- Laboratory of Mycology and Plant Pathology (LAMFU), Department of Chemical and Food Engineering, Universidad de Los Andes, Bogotá, Colombia
- Grupo de Diseño de Productos y Procesos (GDPP), Department of Chemical and Food Engineering, Universidad de Los Andes, Bogotá, Colombia
| | | | - Mariana Restrepo
- Laboratory of Mycology and Plant Pathology (LAMFU), Department of Chemical and Food Engineering, Universidad de Los Andes, Bogotá, Colombia
| | - Vivian Bernal-Galeano
- Laboratory of Mycology and Plant Pathology (LAMFU), Department of Chemical and Food Engineering, Universidad de Los Andes, Bogotá, Colombia
| | - Alejandro Reyes
- Max Planck Tandem Group in Computational Biology, Universidad de Los Andes, Bogotá, Colombia
- Grupo de Biología Computacional y Ecología Microbiana, Department of Biological Sciences, Universidad de Los Andes, Bogotá, Colombia
| | - Andrés González Barrios
- Grupo de Diseño de Productos y Procesos (GDPP), Department of Chemical and Food Engineering, Universidad de Los Andes, Bogotá, Colombia
| | - Bernhard Ø. Palsson
- Systems Biology Research Group, Department of Bioengineering, University of California, San Diego, San Diego, CA, United States
| | - Silvia Restrepo
- Laboratory of Mycology and Plant Pathology (LAMFU), Department of Chemical and Food Engineering, Universidad de Los Andes, Bogotá, Colombia
| | - Adriana Bernal
- Laboratory of Molecular Interactions of Agricultural Microbes, LIMMA, Department of Biological Sciences, Universidad de Los Andes, Bogotá, Colombia
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Liu C, Sun D, Zhu J, Liu J, Liu W. The Regulation of Bacterial Biofilm Formation by cAMP-CRP: A Mini-Review. Front Microbiol 2020; 11:802. [PMID: 32528421 PMCID: PMC7247823 DOI: 10.3389/fmicb.2020.00802] [Citation(s) in RCA: 43] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2020] [Accepted: 04/03/2020] [Indexed: 12/30/2022] Open
Abstract
Biofilms are communities of microorganisms that live in a self-produced extracellular matrix in order to survive in hostile environments. Second messengers, such as c-di-GMP and cAMP, participate in the regulation of biofilm formation. c-di-GMP is a major molecule that is involved in modulating the bacterial transition between a planktonic lifestyle and biofilm formation. Aside from regulating carbon catabolism repression in most bacteria, cAMP has also been found to mediate biofilm formation in many bacteria. Although the underlying mechanisms of biofilm formation mediated by cAMP-CRP have been well-investigated in several bacteria, the regulatory pathways of cAMP-CRP are still poorly understood compared to those of c-di-GMP. Moreover, some bacteria appear to form biofilm in response to changes in carbon source type or concentration. However, the relationship between the carbon metabolisms and biofilm formation remains unclear. This mini-review provides an overview of the cAMP-CRP-regulated pathways involved in biofilm formation in some bacteria. This information will benefit future investigations of the underlying mechanisms that connect between biofilm formation with nutrient metabolism, as well as the cross-regulation between multiple second messengers.
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Affiliation(s)
- Cong Liu
- School of Life Sciences, Jiangsu Normal University, Xuzhou, China
| | - Di Sun
- School of Life Sciences, Jiangsu Normal University, Xuzhou, China
| | - Jingrong Zhu
- School of Life Sciences, Jiangsu Normal University, Xuzhou, China
| | - Jiawen Liu
- School of Life Sciences, Jiangsu Normal University, Xuzhou, China
| | - Weijie Liu
- School of Life Sciences, Jiangsu Normal University, Xuzhou, China
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Two Functional Fatty Acyl Coenzyme A Ligases Affect Free Fatty Acid Metabolism To Block Biosynthesis of an Antifungal Antibiotic in Lysobacter enzymogenes. Appl Environ Microbiol 2020; 86:AEM.00309-20. [PMID: 32144106 PMCID: PMC7205486 DOI: 10.1128/aem.00309-20] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2020] [Accepted: 03/04/2020] [Indexed: 11/20/2022] Open
Abstract
In Lysobacter enzymogenes OH11, RpfB1 and RpfB2 were predicted to encode acyl coenzyme A (CoA) ligases. RpfB1 is located in the Rpf gene cluster. Interestingly, we found an RpfB1 homolog (RpfB2) outside this canonical gene cluster, and nothing is known about its functionality or mechanism. Here, we report that rpfB1 and rpfB2 can functionally replace EcFadD in the Escherichia coli fadD mutant JW1794. RpfB activates long-chain fatty acids (n-C16:0 and n-C18:0) for the corresponding fatty acyl-CoA ligase (FCL) activity in vitro, and Glu-361 plays critical roles in the catalytic mechanism of RpfB1 and RpfB2. Deletion of rpfB1 and rpfB2 resulted in significantly increased heat-stable antifungal factor (HSAF) production, and overexpression of rpfB1 or rpfB2 completely suppressed HSAF production. Deletion of rpfB1 and rpfB2 resulted in increased L. enzymogenes diffusible signaling factor 3 (LeDSF3) synthesis in L. enzymogenes Overall, our results showed that changes in intracellular free fatty acid levels significantly altered HSAF production. Our report shows that intracellular free fatty acids are required for HSAF production and that RpfB affects HSAF production via FCL activity. The global transcriptional regulator Clp directly regulated the expression of rpfB1 and rpfB2 In conclusion, these findings reveal new roles of RpfB in antibiotic biosynthesis in L. enzymogenes IMPORTANCE Understanding the biosynthetic and regulatory mechanisms of heat-stable antifungal factor (HSAF) could improve the yield in Lysobacter enzymogenes Here, we report that RpfB1 and RpfB2 encode acyl coenzyme A (CoA) ligases. Our research shows that RpfB1 and RpfB2 affect free fatty acid metabolism via fatty acyl-CoA ligase (FCL) activity to reduce the substrate for HSAF synthesis and, thereby, block HSAF production in L. enzymogenes Furthermore, these findings reveal new roles for the fatty acyl-CoA ligases RpfB1 and RpfB2 in antibiotic biosynthesis in L. enzymogenes Importantly, the novelty of this work is the finding that RpfB2 lies outside the Rpf gene cluster and plays a key role in HSAF production, which has not been reported in other diffusible signaling factor (DSF)/Rpf-producing bacteria.
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Mishra S, Yang X, Ray S, Fraceto LF, Singh HB. Antibacterial and biofilm inhibition activity of biofabricated silver nanoparticles against Xanthomonas oryzae pv. oryzae causing blight disease of rice instigates disease suppression. World J Microbiol Biotechnol 2020; 36:55. [PMID: 32180020 DOI: 10.1007/s11274-020-02826-1] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2019] [Accepted: 03/03/2020] [Indexed: 10/24/2022]
Abstract
Antimicrobial activity of silver nanoparticles (AgNPs) has been well documented in earlier studies. As their efficient role in combating phytopathogens has begun recently, there is a huge scope to explore their effectiveness in agriculture. Considering the strong antifungal activity of biosynthesized AgNPs (as reported in our previous study), our main aim is to elucidate their antibacterial activity against bacterial plant pathogens to authenticate their wide range of agricultural applications. The present manuscript highlights the potential role of biosynthesized AgNPs against Xanthomonas oryzae pv. oryzae (Xoo) causing disastrous sheath blight disease of rice worldwide. We observed strong antibacterial activity of biosynthesized AgNPs (size ~ 12 nm) against Xoo at 20, 30 and 50 µg/mL concentrations. The significant inhibitory impact of AgNPs on biofilm formation by Xoo was noted even at the lower dose of 5 µg/mL (p = 0.001). Maximum biofilm inhibition (p = 0.000) was caused at 50 µg/mL concentration of AgNPs in comparison to control. Furthermore, disease suppression by biosynthesized AgNPs was authenticated under greenhouse conditions. Foliar spray of AgNPs significantly reduced the blight symptoms in rice sheaths as shown by 9.25% DLA (% Diseased leaf area) as compared to 33.91% DLA in Xoo inoculated rice plants. Altogether, our data suggest that biosynthesized AgNPs based nanoformulation can be applied for successful management of blight disease of rice. In addition, the antibiofilm strategies instigated by AgNPs can be exploited against a wide range of bacterial phytopathogens. In light of rapidly emerging antibiotic-resistant microbial strains, the current work provides an alternate effective platform for the application of nanoformulation for augmenting sustainability in the agriculture.
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Affiliation(s)
- Sandhya Mishra
- CAS Key Laboratory of Tropical Forest Ecology, Xishuangbanna Tropical Botanical Garden, Chinese Academy of Sciences, Menglun, 666303, Yunnan, China
| | - Xiaodong Yang
- CAS Key Laboratory of Tropical Forest Ecology, Xishuangbanna Tropical Botanical Garden, Chinese Academy of Sciences, Menglun, 666303, Yunnan, China
| | - Shatrupa Ray
- Department of Mycology and Plant Pathology, Institute of Agricultural Sciences, Banaras Hindu University, Varanasi, 221005, India
| | - Leonardo Fernandes Fraceto
- Laboratory of Environmental Nanotechnology, Institute of Science and Technology of Sorocaba, São Paulo State University, São Paulo, Brazil
| | - H B Singh
- Department of Mycology and Plant Pathology, Institute of Agricultural Sciences, Banaras Hindu University, Varanasi, 221005, India. .,Somvanshi Research Foundation, 13/21 Vikas Nagar, Lucknow, 226022, India.
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Guo W, Gao J, Wang HJ, Su RY, Sun CY, Gao SH, Liu JZ, Chen GY. Phosphoglycerate Kinase Is Involved in Carbohydrate Utilization, Extracellular Polysaccharide Biosynthesis, and Cell Motility of Xanthomonas axonopodis pv. glycines Independent of Clp. Front Microbiol 2020; 11:91. [PMID: 32117121 PMCID: PMC7018688 DOI: 10.3389/fmicb.2020.00091] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2019] [Accepted: 01/15/2020] [Indexed: 12/04/2022] Open
Abstract
Phosphoglycerate kinase (Pgk), catalyzing the reversible conversions between glycerate-1.3-2P and glycerate-3P, plays an important role in carbohydrate metabolism. Here, we show that a Pgk-deficient mutant (NΔpgk) of Xanthomonas axonopodis pv. glycines (Xag) could grow in medium with glucose, galactose, fructose, mannose, or sucrose, as the sole carbon source, suggesting that Xag may employ Entner-Doudoroff (ED) and pentose phosphate pathway (PPP), but not glycolysis, to catabolize glucose. NΔpgk could not utilize pyruvate, suggesting that Pgk might be essential for gluconeogenesis. Mutation in pgk led to a reduction of extracellular polysaccharide (EPS) biosynthesis, cell motility, and intracellular ATP. As a result, the virulence of NΔpgk was significantly compromised in soybean. NΔpgk could be fully complemented by the wild-type pgk, but not by clp (encoding Crp-like protein). qRT-PCR analyses demonstrated that pgk is regulated by the HrpG/HrpX cascade, but not by Clp. These results suggest that Pgk is involved in carbohydrate utilization, EPS biosynthesis, and cell motility of Xag independent of Clp.
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Affiliation(s)
- Wei Guo
- Institute of Plant Genetics and Developmental Biology, College of Chemistry and Life Sciences, Zhejiang Normal University, Jinhua, China
| | - Jie Gao
- Institute of Plant Genetics and Developmental Biology, College of Chemistry and Life Sciences, Zhejiang Normal University, Jinhua, China
| | - Hong-Jie Wang
- Institute of Plant Genetics and Developmental Biology, College of Chemistry and Life Sciences, Zhejiang Normal University, Jinhua, China
| | - Ru-Yi Su
- Institute of Plant Genetics and Developmental Biology, College of Chemistry and Life Sciences, Zhejiang Normal University, Jinhua, China
| | - Chu-Yun Sun
- Institute of Plant Genetics and Developmental Biology, College of Chemistry and Life Sciences, Zhejiang Normal University, Jinhua, China
| | - Si-Han Gao
- Institute of Plant Genetics and Developmental Biology, College of Chemistry and Life Sciences, Zhejiang Normal University, Jinhua, China
| | - Jian-Zhong Liu
- Institute of Plant Genetics and Developmental Biology, College of Chemistry and Life Sciences, Zhejiang Normal University, Jinhua, China
| | - Gong-You Chen
- College of Agriculture and Biology, Shanghai Jiao Tong University, Shanghai, China
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Brescia F, Marchetti-Deschmann M, Musetti R, Perazzolli M, Pertot I, Puopolo G. The rhizosphere signature on the cell motility, biofilm formation and secondary metabolite production of a plant-associated Lysobacter strain. Microbiol Res 2020; 234:126424. [PMID: 32036275 DOI: 10.1016/j.micres.2020.126424] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2019] [Revised: 01/10/2020] [Accepted: 01/26/2020] [Indexed: 12/15/2022]
Abstract
Lysobacter spp. are common bacterial inhabitants of the rhizosphere of diverse plant species. However, the impact of the rhizosphere conditions on their physiology is still relatively understudied. To provide clues on the behaviour of Lysobacter spp. in this ecological niche, we investigated the physiology of L. capsici AZ78 (AZ78), a biocontrol strain isolated from tobacco rhizosphere, on a common synthetic growth medium (LBA) and on a growth medium containing components of the plant rhizosphere (RMA). The presence of a halo surrounding the AZ78 colony on RMA was a first visible effect related to differences in growth medium composition and it corresponded to the formation of a large outer ring. The lower quantity of nutrients available in RMA as compared with LBA was associated to a higher expression of a gene encoding cAMP-receptor-like protein (Clp), responsible for cell motility and biofilm formation regulation. AZ78 cells on RMA were motile, equipped with cell surface appendages and organised in small groups embedded in a dense layer of fibrils. Metabolic profiling by mass spectrometry imaging revealed increased diversity of analytes produced by AZ78 on RMA as compared with LBA. In particular, putative cyclic lipodepsipeptides, polycyclic tetramate macrolactams, cyclic macrolactams and other putative secondary metabolites with antibiotic activity were identified. Overall, the results obtained in this study shed a light on AZ78 potential to thrive in the rhizosphere by its ability to move, form biofilm and release secondary metabolites.
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Affiliation(s)
- Francesca Brescia
- Department of Sustainable Agro-ecosystems and Bioresources, Research and Innovation Centre, Fondazione Edmund Mach, Via E. Mach 1, 38010, San Michele all'Adige, Italy; PhD school in Agricultural Science and Biotechnology, Department of Agricultural, Food, Environmental and Animal Sciences, University of Udine, Udine, Italy
| | - Martina Marchetti-Deschmann
- Institute of Chemical Technologies and Analytics, TU Wien (Vienna University of Technology), Vienna, 1060, Austria
| | - Rita Musetti
- Department of Agricultural, Food, Environmental and Animal Sciences, University of Udine, Udine, 33100, Italy
| | - Michele Perazzolli
- Department of Sustainable Agro-ecosystems and Bioresources, Research and Innovation Centre, Fondazione Edmund Mach, Via E. Mach 1, 38010, San Michele all'Adige, Italy; Center Agriculture Food Environment (C3A), University of Trento, Via E. Mach 1, 38010, San Michele all'Adige, Italy
| | - Ilaria Pertot
- Department of Sustainable Agro-ecosystems and Bioresources, Research and Innovation Centre, Fondazione Edmund Mach, Via E. Mach 1, 38010, San Michele all'Adige, Italy; Center Agriculture Food Environment (C3A), University of Trento, Via E. Mach 1, 38010, San Michele all'Adige, Italy
| | - Gerardo Puopolo
- Department of Sustainable Agro-ecosystems and Bioresources, Research and Innovation Centre, Fondazione Edmund Mach, Via E. Mach 1, 38010, San Michele all'Adige, Italy; Center Agriculture Food Environment (C3A), University of Trento, Via E. Mach 1, 38010, San Michele all'Adige, Italy.
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Schulte F, Leßmeier L, Voss J, Ortseifen V, Vorhölter FJ, Niehaus K. Regulatory associations between the metabolism of sulfur-containing amino acids and xanthan biosynthesis in Xanthomonas campestris pv. campestris B100. FEMS Microbiol Lett 2019; 366:5289864. [PMID: 30649298 DOI: 10.1093/femsle/fnz005] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2018] [Accepted: 01/14/2019] [Indexed: 02/06/2023] Open
Abstract
The γ-proteobacterium Xanthomonas campestris pv. campestris (Xcc) B100 synthesizes the exopolysaccharide xanthan, a commercially relevant thickening agent produced commonly by industrial scale fermentation. This work was inspired by the observation that methionine is an inhibitor of xanthan formation in growth experiments. Therefore, the global effects of methionine supplementation were characterized through cultivation experiments, genome-wide microarray hybridizations and qRT-PCR. Specific pull down of DNA-binding proteins by using the intergenic regions upstream of xanA, gumB and gumD led to the identification of six transcriptional regulators, among them the LysR-family transcriptional regulator CysB. An insertion mutant of this gene was analyzed by growth experiments, microarray experiments and qRT-PCR. Based on our experimental data, we developed a model that describes the methionine-dependent co-regulation of xanthan and sulfur-containing compounds in Xanthomonas. These data substantially contribute to better understand the impact of methionine as a compound in xanthan production media used in industrial fermentations.
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Affiliation(s)
- Fabian Schulte
- Department of Proteome and Metabolome Research - Bio27, Faculty of Biology, Centrum für Biotechnologie, Universität Bielefeld, Universitätsstr. 25, 33615 Bielefeld, Germany
| | - Lennart Leßmeier
- Chair of Genetics of Prokaryotes, Faculty of Biology, Centrum für Biotechnologie, Universität Bielefeld, Universitätsstr. 25, 33615 Bielefeld, Germany
| | - Julia Voss
- Department of Proteome and Metabolome Research - Bio27, Faculty of Biology, Centrum für Biotechnologie, Universität Bielefeld, Universitätsstr. 25, 33615 Bielefeld, Germany
| | - Vera Ortseifen
- Department of Proteome and Metabolome Research - Bio27, Faculty of Biology, Centrum für Biotechnologie, Universität Bielefeld, Universitätsstr. 25, 33615 Bielefeld, Germany
| | - Frank-Jörg Vorhölter
- Department of Proteome and Metabolome Research - Bio27, Faculty of Biology, Centrum für Biotechnologie, Universität Bielefeld, Universitätsstr. 25, 33615 Bielefeld, Germany
| | - Karsten Niehaus
- Department of Proteome and Metabolome Research - Bio27, Faculty of Biology, Centrum für Biotechnologie, Universität Bielefeld, Universitätsstr. 25, 33615 Bielefeld, Germany
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Yang F, Xue D, Tian F, Hutchins W, Yang CH, He C. Identification of c-di-GMP Signaling Components in Xanthomonas oryzae and Their Orthologs in Xanthomonads Involved in Regulation of Bacterial Virulence Expression. Front Microbiol 2019; 10:1402. [PMID: 31354637 PMCID: PMC6637768 DOI: 10.3389/fmicb.2019.01402] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2018] [Accepted: 06/04/2019] [Indexed: 11/13/2022] Open
Abstract
Xanthomonas oryzae pv. oryzae (Xoo) causes bacterial leaf blight of rice, one of the most devastating bacterial diseases of this staple crop worldwide. Xoo produces a range of virulence-related factors to facilitate its pathogenesis in rice, however, the regulatory mechanisms of Xoo virulence expression have been not fully elucidated. Recent studies have revealed that virulence factor production is regulated via cyclic dimeric guanosine monophosphate (c-di-GMP) signaling pathway that is well-conserved in Xoo and other Xanthomonas species. A set of GGDEF, EAL, HD-GYP, and PilZ domain proteins with diverse signal sensory domains for c-di-GMP synthesis, hydrolysis, and binding is encoded in the Xoo genome. Bioinformatic, genetic, and biochemical analysis has identified an array of diguanylate cyclases (DGCs) and phosphodiesterases (PDEs), as well as degenerate GGDEF/EAL, PilZ domain proteins along with a transcription regulator. These signaling components have been characterized to regulate various bacterial cellular processes, such as virulence, exopolysaccharide (EPS) production, biofilm formation, motility, and adaptation at the transcriptional, post-translational, and protein-protein interaction levels. This review summarized the recent progress in understanding the importance and complexity of c-di-GMP signaling in regulating bacterial virulence expression, highlighting the identified key signal elements and orthologs found in Xanthomonads, discussing the diverse functions of GGDEF/EAL/HD-GYP domains, existence of a complicated multifactorial network between DGCs, PDEs, and effectors, and further exploration of the new c-di-GMP receptor domains. These findings and knowledge lay the groundwork for future experimentation to further elucidate c-di-GMP regulatory circuits involved in regulation of bacterial pathogenesis.
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Affiliation(s)
- Fenghuan Yang
- State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, China
| | - Dingrong Xue
- State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, China
| | - Fang Tian
- State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, China
| | - William Hutchins
- Department of Biology, Carthage College, Kenosha, WI, United States
| | - Ching-Hong Yang
- Department of Biological Sciences, University of Wisconsin-Milwaukee, Milwaukee, WI, United States
| | - Chenyang He
- State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, China
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Guo W, Gao J, Chen Q, Ma B, Fang Y, Liu X, Chen G, Liu JZ. Crp-Like Protein Plays Both Positive and Negative Roles in Regulating the Pathogenicity of Bacterial Pustule Pathogen Xanthomonas axonopodis pv. glycines. PHYTOPATHOLOGY 2019; 109:1171-1183. [PMID: 30730787 DOI: 10.1094/phyto-07-18-0225-r] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
The global regulator Crp-like protein (Clp) is positively involved in the production of virulence factors in some of the Xanthomonas spp. However, the functional importance of Clp in X. axonopodis pv. glycines has not been investigated previously. Here, we showed that deletion of clp led to significant reduction in the virulence of X. axonopodis pv. glycines in soybean, which was highly correlated with the drastic reductions in carbohydrates utilization, extracellular polysaccharide (EPS) production, biofilm formation, cell motility, and synthesis of cell wall degrading enzymes (CWDEs). These significantly impaired properties in the clp mutant were completely rescued by a single-copy integration of the wild-type clp into the mutant chromosome via homologous recombination. Interestingly, overexpression of clp in the wild-type strain resulted in significant increases in cell motility and synthesis of the CWDEs. To our surprise, significant reductions in carbohydrates utilization, EPS production, biofilm formation, and the protease activity were observed in the wild-type strain overexpressing clp, suggesting that Clp also plays a negative role in these properties. Furthermore, quantitative reverse transcription polymerase chain reaction analysis suggested that clp was positively regulated by the diffusible signal factor-mediated quorum-sensing system and the HrpG/HrpX cascade. Taken together, our results reveal that Clp functions as both activator and repressor in multiple biological processes in X. axonopodis pv. glycines that are essential for its full virulence.
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Affiliation(s)
- Wei Guo
- 1 Institute of Plant Genetics and Developmental Biology, College of Chemistry and Life Sciences, Zhejiang Normal University, Jinhua 321004, China
| | - Jie Gao
- 1 Institute of Plant Genetics and Developmental Biology, College of Chemistry and Life Sciences, Zhejiang Normal University, Jinhua 321004, China
| | - Qingshan Chen
- 2 College of Agriculture, Northeast Agricultural University, Harbin 150030, China; and
| | - Bojun Ma
- 1 Institute of Plant Genetics and Developmental Biology, College of Chemistry and Life Sciences, Zhejiang Normal University, Jinhua 321004, China
| | - Yuan Fang
- 1 Institute of Plant Genetics and Developmental Biology, College of Chemistry and Life Sciences, Zhejiang Normal University, Jinhua 321004, China
| | - Xia Liu
- 1 Institute of Plant Genetics and Developmental Biology, College of Chemistry and Life Sciences, Zhejiang Normal University, Jinhua 321004, China
| | - Gongyou Chen
- 3 College of Agriculture and Biology, Shanghai Jiao Tong University, Shanghai 200240, China
| | - Jian-Zhong Liu
- 1 Institute of Plant Genetics and Developmental Biology, College of Chemistry and Life Sciences, Zhejiang Normal University, Jinhua 321004, China
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44
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Távora FTPK, Santos C, Maximiano MR, Murad AM, Oliveira-Neto OB, Megias E, Reis Junior FB, Franco OL, Mehta A. Pan Proteome of Xanthomonas campestris pv. campestris Isolates Contrasting in Virulence. Proteomics 2019; 19:e1900082. [PMID: 31050381 DOI: 10.1002/pmic.201900082] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2019] [Revised: 03/30/2019] [Indexed: 11/07/2022]
Abstract
Fully sequenced genomes of Xanthomonas campestris pv. campestris (Xcc) strains are reported. However, intra-pathovar differences are still intriguing and far from clear. In this work, the contrasting virulence between two isolates of Xcc - Xcc51 (more virulent) and XccY21 (less virulent) is evaluated by determining their pan proteome profiles. The bacteria are grown in NYG and XVM1 (optimal for induction of hrp regulon) broths and collected at the max-exponential growth phase. Shotgun proteomics reveals a total of 329 proteins when Xcc isolates are grown in XVM1. A comparison of both profiles reveals 47 proteins with significant abundance fluctuations, out of which, 39 show an increased abundance in Xcc51 and are mainly involved in virulence/adaptation mechanisms, genetic information processing, and membrane receptor/iron transport systems, such as BfeA, BtuB, Cap, Clp, Dcp, FyuA, GroEs, HpaG, Tig, and OmpP6. Several differential proteins are further analyzed by qRT-PCR, which reveals a similar expression pattern to the protein abundance. The data shed light on the complex Xcc pathogenicity mechanisms and point out a set of proteins related to the higher virulence of Xcc51. This information is essential for the development of more efficient strategies aiming at the control of black rot disease.
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Affiliation(s)
- Fabiano T P K Távora
- Embrapa Recursos Genéticos e Biotecnologia, Brasília, CEP 70770-917, DF, Brazil.,Departamento de Genética e Biotecnologia, Instituto de Biologia, Universidade Federal de Juiz de Fora, Juiz de Fora, CEP 36036-900, MG, Brazil
| | - Cristiane Santos
- Embrapa Recursos Genéticos e Biotecnologia, Brasília, CEP 70770-917, DF, Brazil.,Departamento de Genética e Biotecnologia, Instituto de Biologia, Universidade Federal de Juiz de Fora, Juiz de Fora, CEP 36036-900, MG, Brazil
| | - Mariana R Maximiano
- Embrapa Recursos Genéticos e Biotecnologia, Brasília, CEP 70770-917, DF, Brazil.,Departamento de Genética e Biotecnologia, Instituto de Biologia, Universidade Federal de Juiz de Fora, Juiz de Fora, CEP 36036-900, MG, Brazil
| | - André M Murad
- Embrapa Recursos Genéticos e Biotecnologia, Brasília, CEP 70770-917, DF, Brazil
| | - Osmundo Brilhante Oliveira-Neto
- Embrapa Recursos Genéticos e Biotecnologia, Brasília, CEP 70770-917, DF, Brazil.,Departamento de Bioquímica e Biologia Molecular, Escola de Medicina, FACIPLAC, Brasília, CEP 72460-000, DF, Brazil
| | - Esaú Megias
- Embrapa Recursos Genéticos e Biotecnologia, Brasília, CEP 70770-917, DF, Brazil
| | | | - Octávio L Franco
- Departamento de Genética e Biotecnologia, Instituto de Biologia, Universidade Federal de Juiz de Fora, Juiz de Fora, CEP 36036-900, MG, Brazil.,Centro de Análises Proteômicas e Bioquímicas, Programa de Pós-Graduação em Ciências Genômicas e Biotecnologia, Universidade Católica de Brasília, Brasília, CEP 70790-160, DF, Brazil.,S-Inova Biotech, Programa de Pós-Graduação em Biotecnologia, Universidade Católica Dom Bosco, Campo Grande, CEP 79117-900, MS, Brazil
| | - Angela Mehta
- Embrapa Recursos Genéticos e Biotecnologia, Brasília, CEP 70770-917, DF, Brazil
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45
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Diab AA, Cao XQ, Chen H, Song K, Zhou L, Chen B, He YW. BDSF Is the Predominant In-Planta Quorum-Sensing Signal Used During Xanthomonas campestris Infection and Pathogenesis in Chinese Cabbage. MOLECULAR PLANT-MICROBE INTERACTIONS : MPMI 2019; 32:240-254. [PMID: 30570452 DOI: 10.1094/mpmi-07-18-0197-r] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Xanthomonas campestris pv. campestris uses the diffusible signal factor (DSF) family of quorum-sensing (QS) signals to coordinate virulence and adaptation. DSF family signals have been well-characterized using laboratory-based cell cultures. The in-planta QS signal used during X. campestris pv. campestris infection remains unclear. To achieve this goal, we first mimic in-planta X. campestris pv. campestris growth conditions by supplementing the previously developed XYS medium with cabbage hydrolysate and found that the dominant signal produced in these conditions was BDSF. Secondly, by using XYS medium supplemented with diverse plant-derived compounds, we examined the effects of diverse plant-derived compounds on the biosynthesis of DSF family signals. Several compounds were found to promote biosynthesis of BDSF. Finally, using an X. campestris pv. campestris ΔrpfB-Chinese cabbage infection model and an ultra-performance liquid chromatographic-time of flight-mass spectrometry-based assay, BDSF was found to comprise >70% of the DSF family signals present in infected cabbage tissue. BDSF at a concentration of 2.0 μM induced both protease activity and engXCA expression. This is the first report to directly show that BDSF is the predominant in-planta QS signal used during X. campestris pv. campestris infection. It provides a better understanding of the molecular interactions between X. campestris pv. campestris and its cruciferous hosts and also provides the logical target for designing strategies to counteract BDSF signaling and, thus, infection. Further studies are needed to get an exact idea about the DSF production dynamics of the wild-type strain inside the plant.
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Affiliation(s)
- Abdelgader Abdeen Diab
- 1 State Key Laboratory of Microbial Metabolism, Joint International Research Laboratory of Metabolic & Developmental Sciences, School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai 200240, China; and
| | - Xue-Qiang Cao
- 1 State Key Laboratory of Microbial Metabolism, Joint International Research Laboratory of Metabolic & Developmental Sciences, School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai 200240, China; and
| | - Hui Chen
- 1 State Key Laboratory of Microbial Metabolism, Joint International Research Laboratory of Metabolic & Developmental Sciences, School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai 200240, China; and
| | - Kai Song
- 1 State Key Laboratory of Microbial Metabolism, Joint International Research Laboratory of Metabolic & Developmental Sciences, School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai 200240, China; and
| | - Lian Zhou
- 2 Zhiyuan Innovation Research Centre, Student Innovation Centre, Zhiyuan College, Shanghai Jiao Tong University
| | - Bo Chen
- 1 State Key Laboratory of Microbial Metabolism, Joint International Research Laboratory of Metabolic & Developmental Sciences, School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai 200240, China; and
| | - Ya-Wen He
- 1 State Key Laboratory of Microbial Metabolism, Joint International Research Laboratory of Metabolic & Developmental Sciences, School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai 200240, China; and
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46
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Li L, Li J, Zhang Y, Wang N. Diffusible signal factor (DSF)-mediated quorum sensing modulates expression of diverse traits in Xanthomonas citri and responses of citrus plants to promote disease. BMC Genomics 2019; 20:55. [PMID: 30654743 PMCID: PMC6337780 DOI: 10.1186/s12864-018-5384-4] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2018] [Accepted: 12/18/2018] [Indexed: 01/07/2023] Open
Abstract
Background The gram-negative Xanthomonas genus contains a large group of economically important plant pathogens, which cause severe diseases on many crops worldwide. The diffusible signal factor (DSF) - mediated quorum sensing (QS) system coordinates expression of virulence factors in plant pathogenic Xanthomonas spp. However, the regulatory effects of this system during the Xanthomonas- plant interactions remain unclear from both the pathogen and host aspects. Results In this study, we investigated the in planta DSF- mediated QS regulon of X. citri subsp. citri (Xac), the causal agent of citrus canker. We also characterized the transcriptional responses of citrus plants to DSF-mediated Xac infection via comparing the gene expression patterns of citrus trigged by wild type Xac strain 306 with those trigged by its DSF- deficient (∆rpfF) mutant using the dual RNA-seq approach. Comparative global transcript profiles of Xac strain 306 and the ∆rpfF mutant during host infection revealed that DSF- mediated QS specifically modulates bacterial adaptation, nutrition uptake and metabolisms, stress tolerance, virulence, and signal transduction to favor host infection. The transcriptional responses of citrus to DSF-mediated Xac infection are characterized by downregulation of photosynthesis genes and plant defense related genes, suggesting photosynthetically inactive reactions and repression of defense responses. Alterations of phytohormone metabolism and signaling pathways were also triggered by DSF-mediated Xac infection to benefit the pathogen. Conclusions Collectively, our findings provide new insight into the DSF- mediated QS regulation during plant-pathogen interactions and advance the understanding of traits used by Xanthomonas to promote infection on host plants. Electronic supplementary material The online version of this article (10.1186/s12864-018-5384-4) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Lei Li
- Chinese Academy of Agricultural Sciences, Institute of Vegetables and Flowers, Beijing, 100081, China.,Citrus Research and Education Center, Department of Microbiology and Cell Science, University of Florida, Lake Alfred, FL, 33850, USA
| | - Jinyun Li
- Citrus Research and Education Center, Department of Microbiology and Cell Science, University of Florida, Lake Alfred, FL, 33850, USA
| | - Yunzeng Zhang
- Citrus Research and Education Center, Department of Microbiology and Cell Science, University of Florida, Lake Alfred, FL, 33850, USA
| | - Nian Wang
- Citrus Research and Education Center, Department of Microbiology and Cell Science, University of Florida, Lake Alfred, FL, 33850, USA.
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47
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Liu G, Su H, Sun H, Lu G, Tang J. Competitive control of endoglucanase gene engXCA expression in the plant pathogen Xanthomonas campestris by the global transcriptional regulators HpaR1 and Clp. MOLECULAR PLANT PATHOLOGY 2019; 20:51-68. [PMID: 30091270 PMCID: PMC6430473 DOI: 10.1111/mpp.12739] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/11/2023]
Abstract
Transcriptional regulators are key players in pathways that allow bacteria to alter gene expression in response to environmental conditions. However, work to understand how such transcriptional regulatory networks interact in bacterial plant pathogens is limited. Here, in the phytopathogen Xanthomonas campestris, we demonstrate that the global transcriptional regulator HpaR1 influences many of the same genes as another global regulator Clp, including the engXCA gene that encodes extracellular endoglucanase. We demonstrate that HpaR1 facilitates the binding of RNA polymerase to the engXCA promoter. In addition, we show that HpaR1 binds directly to the engXCA promoter. Furthermore, our in vitro tests characterize two binding sites for Clp within the engXCA promoter. Interestingly, one of these sites overlaps with the HpaR1 binding site. Mobility shift assays reveal that HpaR1 has greater affinity for binding to the engXCA promoter. This observation is supported by promoter activity assays, which show that the engXCA expression level is lower when both HpaR1 and Clp are present together, rather than alone. The data also reveal that HpaR1 and Clp activate engXCA gene expression by binding directly to its promoter. This transcriptional activation is modulated as both regulators compete to bind to overlapping sites on the engXCA promoter. Bioinformatics analysis suggests that this mechanism may be used broadly in Xanthomonas campestris pv. campestris (Xcc) and is probably widespread in Xanthomonads and, potentially, other bacteria. Taken together, these data support a novel mechanism of competitive activation by two global regulators of virulence gene expression in Xcc which is probably widespread in Xanthomonads and, potentially, other bacteria.
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Affiliation(s)
- Guo‐Fang Liu
- State Key Laboratory for Conservation and Utilization of Subtropical Agro‐bioresources, College of Life Science and TechnologyGuangxi University100 Daxue RoadNanningGuangxi530004China
| | - Hui‐Zhao Su
- State Key Laboratory for Conservation and Utilization of Subtropical Agro‐bioresources, College of Life Science and TechnologyGuangxi University100 Daxue RoadNanningGuangxi530004China
| | - Han‐Yang Sun
- State Key Laboratory for Conservation and Utilization of Subtropical Agro‐bioresources, College of Life Science and TechnologyGuangxi University100 Daxue RoadNanningGuangxi530004China
| | - Guang‐Tao Lu
- State Key Laboratory for Conservation and Utilization of Subtropical Agro‐bioresources, College of Life Science and TechnologyGuangxi University100 Daxue RoadNanningGuangxi530004China
| | - Ji‐Liang Tang
- State Key Laboratory for Conservation and Utilization of Subtropical Agro‐bioresources, College of Life Science and TechnologyGuangxi University100 Daxue RoadNanningGuangxi530004China
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48
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Phosphodiesterase EdpX1 Promotes Xanthomonas oryzae pv. oryzae Virulence, Exopolysaccharide Production, and Biofilm Formation. Appl Environ Microbiol 2018; 84:AEM.01717-18. [PMID: 30217836 DOI: 10.1128/aem.01717-18] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2018] [Accepted: 09/06/2018] [Indexed: 12/22/2022] Open
Abstract
In Xanthomonas oryzae pv. oryzae, the bacterial blight pathogen of rice, there are over 20 genes encoding GGDEF, EAL, and HD-GYP domains, which are potentially involved in the metabolism of second messenger c-di-GMP. In this study, we focused on the characterization of an EAL domain protein, EdpX1. Deletion of the edpX1 gene resulted in a 2-fold increase in the intracellular c-di-GMP levels, which were restored to the wild-type levels in the complemented ΔedpX1(pB-edpX1) strain, demonstrating that EdpX1 is an active phosphodiesterase (PDE) in X. oryzae pv. oryzae. In addition, colorimetric assays further confirmed the PDE activity of EdpX1 by showing that the E153A mutation at the EAL motif strongly reduced its activity. Virulence assays on the leaves of susceptible rice showed that the ΔedpX1 mutant was severely impaired in causing disease symptoms. In trans expression of wild-type edpX1, but not edpX1 E153A, was able to complement the weakened virulence phenotype. These results indicated that an active EAL domain is required for EdpX1 to regulate the virulence of X. oryzae pv. oryzae. We then demonstrated that the ΔedpX1 mutant was defective in secreting exopolysaccharide (EPS) and forming biofilms. The expression of edpX1 in the ΔedpX1 mutant, but not edpX1 E153A, restored the defective phenotypes to near-wild-type levels. In addition, we observed that EdpX1-green fluorescent protein (EdpX1-GFP) exhibited multiple subcellular localization foci, and this pattern was dependent on its transmembrane (TM) region, which did not seem to directly contribute to the regulatory function of EdpX1. Thus, we concluded that EdpX1 exhibits PDE activity to control c-di-GMP levels, and its EAL domain is necessary and sufficient for its regulation of virulence in X. oryzae pv. oryzae.IMPORTANCE Bacteria utilize c-di-GMP as a second messenger to regulate various biological functions. The synthesis and degradation of c-di-GMP are catalyzed by GGDEF domains and an EAL or HD-GYP domain, respectively. Multiple genes encoding these domains are often found in one bacterial strain. For example, in the genome of X. oryzae pv. oryzae PXO99A, 26 genes encoding proteins containing these domains were identified. Therefore, to fully appreciate the complexity and specificity of c-di-GMP signaling in X. oryzae pv. oryzae, the enzymatic activities and regulatory functions of each GGDEF, EAL, and HD-GYP domain protein need to be elucidated. In this study, we showed that the EAL domain protein EdpX1 is a major PDE to regulate diverse virulence phenotypes through the c-di-GMP signaling pathway.
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49
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Pandey SS, Patnana PK, Padhi Y, Chatterjee S. Low-iron conditions induces the hypersensitive reaction and pathogenicity hrp genes expression in Xanthomonas and is involved in modulation of hypersensitive response and virulence. ENVIRONMENTAL MICROBIOLOGY REPORTS 2018; 10:522-531. [PMID: 29687657 DOI: 10.1111/1758-2229.12650] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/13/2017] [Revised: 04/03/2018] [Accepted: 04/05/2018] [Indexed: 06/08/2023]
Abstract
Expression of hrp (hypersensitive reaction and pathogenicity) genes inside the host is crucial for virulence of phytopathogenic bacteria. The hrp genes encode components of type3 secretion system (T3SS), HR elicitors and several regulators, which are involved in the co-ordinated expression of hrp genes in the host environment and in hrp inducing chemically defined medium. However, little is known about specific host or environmental factors which may play a role in the induction of hrp gene expression. In this study, we show that iron-limiting condition elicits induced expression of hrp genes, including type3 secretion system (T3SS) and effectors (T3E). Expression analysis using qRT-PCR and promoter probe strains suggest significant induction in the expression of Hrp and T3S-associated genes of Xanthomonas campestris pv. campestris (Xcc) under low-iron condition, and is suppressed by exogenous supplementation of iron. Furthermore, we show that with exogenous iron supplementation, wild type Xcc exhibited reduced disease symptoms in host-plant, and exhibited significant reduction in HR and callose deposition in the non-host plants. Xanthomonas oryzae and oryzicola pathovars also exhibited the iron affect, albeit to a lesser extend compared with the Xcc. Overall, our results suggest that low-iron condition inside the host may play a crucial role in pathogenicity.
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Affiliation(s)
- Sheo Shankar Pandey
- Centre for DNA Fingerprinting and Diagnostics, Nampally, Hyderabad 500001, India
- Graduate Studies, Manipal University, Manipal, India
| | | | - Yasobanta Padhi
- Centre for DNA Fingerprinting and Diagnostics, Nampally, Hyderabad 500001, India
- Graduate Studies, Manipal University, Manipal, India
| | - Subhadeep Chatterjee
- Centre for DNA Fingerprinting and Diagnostics, Nampally, Hyderabad 500001, India
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50
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Jiang BL, Jiang GF, Liu W, Yang LC, Yang LY, Wang L, Hang XH, Tang JL. RpfC regulates the expression of the key regulator hrpX of the hrp/T3SS system in Xanthomonas campestris pv. campestris. BMC Microbiol 2018; 18:103. [PMID: 30176800 PMCID: PMC6122198 DOI: 10.1186/s12866-018-1233-5] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2018] [Accepted: 08/15/2018] [Indexed: 12/02/2022] Open
Abstract
Background The Gram-negative phytopathogenic bacterium Xanthomonas campestris pv. campestris recruits the hrp/T3SS system to inject pathogenicity effector proteins into host cells and uses the rpf/DSF cell-cell signaling system to regulate the expression of virulence factors such as extracellular enzymes and polysaccharide. Whether these two systems have any connection is unknown. Methods Positive regulator candidates affecting hrpX expression were identified by sacB strategy. The transcriptional expression was determined by qRT-PCR and GUS activity analysis. Transcriptome analysis was performed by RNA deep-sequencing. The hypersensitive response (HR) was determined in the nonhost plant pepper ECW-10R and electrolyte leakage assay. Results Mutation of the gene encoding the sensor RpfC of the rpf/DSF system significantly reduced the expression of hrpX, the key regulator of the hrp/T3SS system, all of the genes in the hrp cluster and most reported type III effector genes. Mutation of rpfG did not affect the expression of hrpX. The rpfC mutant showed a delayed and weakened HR induction. Conclusions RpfC positively regulates the expression of hrpX independent of RpfG, showing a complex regulatory network linking the rpf/DSF and hrp/T3SS systems. Electronic supplementary material The online version of this article (10.1186/s12866-018-1233-5) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Bo-Le Jiang
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-bioresources, College of Life Science and Technology, Guangxi University, 100 Daxue Road, Nanning, 530004, Guangxi, China
| | - Guo-Feng Jiang
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-bioresources, College of Life Science and Technology, Guangxi University, 100 Daxue Road, Nanning, 530004, Guangxi, China
| | - Wei Liu
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-bioresources, College of Life Science and Technology, Guangxi University, 100 Daxue Road, Nanning, 530004, Guangxi, China
| | - Li-Chao Yang
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-bioresources, College of Life Science and Technology, Guangxi University, 100 Daxue Road, Nanning, 530004, Guangxi, China
| | - Li-Yan Yang
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-bioresources, College of Life Science and Technology, Guangxi University, 100 Daxue Road, Nanning, 530004, Guangxi, China
| | - Lin Wang
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-bioresources, College of Life Science and Technology, Guangxi University, 100 Daxue Road, Nanning, 530004, Guangxi, China
| | - Xiao-Hong Hang
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-bioresources, College of Life Science and Technology, Guangxi University, 100 Daxue Road, Nanning, 530004, Guangxi, China
| | - Ji-Liang Tang
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-bioresources, College of Life Science and Technology, Guangxi University, 100 Daxue Road, Nanning, 530004, Guangxi, China.
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