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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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Song K, Li R, Cui Y, Chen B, Zhou L, Han W, Jiang B, He Y. The phytopathogen Xanthomonas campestris senses and effluxes salicylic acid via a sensor HepR and an RND family efflux pump to promote virulence in host plants. MLIFE 2024; 3:430-444. [PMID: 39359673 PMCID: PMC11442134 DOI: 10.1002/mlf2.12140] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 11/27/2023] [Revised: 04/22/2024] [Accepted: 06/06/2024] [Indexed: 10/04/2024]
Abstract
Salicylic acid (SA) plays an essential role in plant defense against biotrophic and semi-biotrophic pathogens. Following pathogen recognition, SA biosynthesis dramatically increases at the infection site of the host plant. The manner in which pathogens sense and tolerate the onslaught of SA stress to survive in the plant following infection remains to be understood. The objective of this work was to determine how the model phytopathogen Xanthomonas campestris pv. campestris (Xcc) senses and effluxes SA during infection inside host plants. First, RNA-Seq analysis identified an SA-responsive operon Xcc4167-Xcc4171, encoding a MarR family transcription factor HepR and an RND (resistance-nodulation-cell division) family efflux pump HepABCD in Xcc. Electrophoretic mobility shift assays and DNase I footprint analysis revealed that HepR negatively regulated hepABCD expression by specifically binding to an AT-rich region of the promoter of the hepRABCD operon, Phep. Second, isothermal titration calorimetry and further genetic analysis suggest that HepR is a novel SA sensor. SA binding released HepR from its cognate promoter Phep and then induced the expression of hepABCD. Third, the RND family efflux pump HepABCD was responsible for SA efflux. The hepRABCD cluster was also involved in the regulation of culture pH and quorum sensing signal diffusible signaling factor turnover. Finally, the hepRABCD cluster was transcribed during the XC1 infection of Chinese radish and was required for the full virulence of Xcc in Chinese radish and cabbage. These findings suggest that the ability of Xcc to co-opt the plant defense signal SA to activate the multidrug efflux pump may have evolved to ensure Xcc survival and virulence in susceptible host plants.
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Affiliation(s)
- Kai Song
- State Key Laboratory of Microbial Metabolism, Joint International Research Laboratory of Metabolic and Developmental Sciences, School of Life Sciences and BiotechnologyShanghai Jiao Tong UniversityShanghaiChina
| | - Ruifang Li
- Guangxi Key Laboratory of Biology for Crop Diseases and Insect Pests, Plant Protection Research InstituteGuangxi Academy of Agricultural SciencesNanningChina
| | - Ying Cui
- State Key Laboratory of Microbial Metabolism, Joint International Research Laboratory of Metabolic and Developmental Sciences, School of Life Sciences and BiotechnologyShanghai Jiao Tong UniversityShanghaiChina
| | - Bo Chen
- State Key Laboratory of Microbial Metabolism, Joint International Research Laboratory of Metabolic and Developmental Sciences, School of Life Sciences and BiotechnologyShanghai Jiao Tong UniversityShanghaiChina
| | - Lian Zhou
- Zhiyuan Innovative Research CenterShanghai Jiao Tong UniversityShanghaiChina
| | - Wenying Han
- State Key Laboratory for Conservation and Utilization of Subtropical Agro‐bioresources, College of Life Science and TechnologyGuangxi UniversityNanningChina
| | - Bo‐Le Jiang
- State Key Laboratory for Conservation and Utilization of Subtropical Agro‐bioresources, College of Life Science and TechnologyGuangxi UniversityNanningChina
| | - Ya‐Wen He
- State Key Laboratory of Microbial Metabolism, Joint International Research Laboratory of Metabolic and Developmental Sciences, School of Life Sciences and BiotechnologyShanghai Jiao Tong UniversityShanghaiChina
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Li K, Ma C, Zhou X, Xiong C, Wang B, Wang Y, Liu F. Regulatory Effects of Diverse DSF Family Quorum-Sensing Signals in Plant-Associated Bacteria. MOLECULAR PLANT-MICROBE INTERACTIONS : MPMI 2024; 37:6-14. [PMID: 37880815 DOI: 10.1094/mpmi-05-23-0074-cr] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/27/2023]
Abstract
Numerous bacterial species employ diffusible signal factor (DSF)-based quorum sensing (QS) as a widely conserved cell-cell signaling communication system to collectively regulate various behaviors crucial for responding to environmental changes. cis-11-Methyl-dodecenoic acid, known as DSF, was first identified as a signaling molecule in Xanthomonas campestris pv. campestris. Subsequently, many structurally related molecules have been identified in different bacterial species. This review aims to provide an overview of current understanding regarding the biosynthesis and regulatory role of DSF signals in both pathogenic bacteria and a biocontrol bacterium. Recent studies have revealed that the DSF-based QS system regulates antimicrobial factor production in a cyclic dimeric GMP-independent manner in the biocontrol bacterium Lysobacter enzymogenes. Additionally, the DSF family signals have been found to be involved in suppressing plant innate immunity. The discovery of these diverse signaling mechanisms holds significant promise for developing novel strategies to combat stubborn plant pathogens. [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)
- Kaihuai Li
- Department of Plant Pathology, College of Agriculture, Guizhou University, Guiyang 550025, China
- Key Laboratory of Agricultural Microbiology, College of Agriculture, Guizhou University, Guiyang 550025, China
- Institute of Vegetable Industry Technology Research, Guizhou University, Guiyang 550025, China
| | - Chaoyun Ma
- Department of Plant Pathology, College of Agriculture, Guizhou University, Guiyang 550025, China
- Key Laboratory of Agricultural Microbiology, College of Agriculture, Guizhou University, Guiyang 550025, China
| | - Xue Zhou
- Department of Plant Pathology, College of Agriculture, Guizhou University, Guiyang 550025, China
- Key Laboratory of Agricultural Microbiology, College of Agriculture, Guizhou University, Guiyang 550025, China
| | - Chunlan Xiong
- Department of Plant Pathology, College of Agriculture, Guizhou University, Guiyang 550025, China
- Key Laboratory of Agricultural Microbiology, College of Agriculture, Guizhou University, Guiyang 550025, China
| | - Bo Wang
- Institute of Plant Protection, Jiangsu Academy of Agricultural Sciences, Nanjing 210014, China
| | - Yong Wang
- Department of Plant Pathology, College of Agriculture, Guizhou University, Guiyang 550025, China
- Key Laboratory of Agricultural Microbiology, College of Agriculture, Guizhou University, Guiyang 550025, China
- Institute of Vegetable Industry Technology Research, Guizhou University, Guiyang 550025, China
| | - Fengquan Liu
- Department of Plant Pathology, College of Agriculture, Guizhou University, Guiyang 550025, China
- Key Laboratory of Agricultural Microbiology, College of Agriculture, Guizhou University, Guiyang 550025, China
- Institute of Plant Protection, Jiangsu Academy of Agricultural Sciences, Nanjing 210014, China
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Gao ZM, Xu T, Chen HG, Lu R, Tao J, Wang HB, Qiu JW, Wang Y. Early genome erosion and internal phage-symbiont-host interaction in the endosymbionts of a cold-seep tubeworm. iScience 2023; 26:107033. [PMID: 37389180 PMCID: PMC10300362 DOI: 10.1016/j.isci.2023.107033] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2022] [Revised: 03/11/2023] [Accepted: 05/31/2023] [Indexed: 07/01/2023] Open
Abstract
Endosymbiosis with chemosynthetic Gammaproteobacteria is widely recognized as an adaptive mechanism of siboglinid tubeworms, yet evolution of these endosymbionts and their driving forces remain elusive. Here, we report a finished endosymbiont genome (HMS1) of the cold-seep tubeworm Sclerolinum annulatum. The HMS1 genome is small in size, with abundant prophages and transposable elements but lacking gene sets coding for denitrification, hydrogen oxidization, oxidative phosphorylation, vitamin biosynthesis, cell pH and/or sodium homeostasis, environmental sensing, and motility, indicative of early genome erosion and adaptive evolution toward obligate endosymbiosis. Unexpectedly, a prophage embedded in the HMS1 genome undergoes lytic cycle. Highly expressed ROS scavenger and LexA repressor genes indicate that the tubeworm host likely activates the lysogenic phage into lytic cycle through the SOS response to regulate endosymbiont population and harvest nutrients. Our findings indicate progressive evolution of Sclerolinum endosymbionts toward obligate endosymbiosis and expand the knowledge about phage-symbiont-host interaction in deep-sea tubeworms.
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Affiliation(s)
- Zhao-Ming Gao
- Institute of Deep Sea Science and Engineering, Chinese Academy of Sciences, Sanya 572000, China
- HKUST-CAS Sanya Joint Laboratory of Marine Science Research, Chinese Academy of Sciences, Sanya 572000, China
| | - Ting Xu
- Department of Ocean Science, The Hong Kong University of Science and Technology, Hong Kong, China
- Southern Marine Science and Engineering Guangdong Laboratory (Guangzhou), Guangzhou 511458, China
| | - Hua-Guan Chen
- Institute of Deep Sea Science and Engineering, Chinese Academy of Sciences, Sanya 572000, China
- University of Chinese Academy of Sciences, Beijing 101408, China
| | - Rui Lu
- Institute of Deep Sea Science and Engineering, Chinese Academy of Sciences, Sanya 572000, China
- University of Chinese Academy of Sciences, Beijing 101408, China
| | - Jun Tao
- MLR Key Laboratory of Marine Mineral Resources, Guangzhou Marine Geological Survey, China Geological Survey, Guangzhou 511458, China
| | - Hong-Bin Wang
- MLR Key Laboratory of Marine Mineral Resources, Guangzhou Marine Geological Survey, China Geological Survey, Guangzhou 511458, China
| | - Jian-Wen Qiu
- Southern Marine Science and Engineering Guangdong Laboratory (Guangzhou), Guangzhou 511458, China
- Department of Biology, Hong Kong Baptist University, Hong Kong, China
| | - Yong Wang
- Institute of Deep Sea Science and Engineering, Chinese Academy of Sciences, Sanya 572000, China
- HKUST-CAS Sanya Joint Laboratory of Marine Science Research, Chinese Academy of Sciences, Sanya 572000, China
- Institute for Ocean Engineering, Shenzhen International Graduate School, Tsinghua University, Shenzhen 518000, China
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Zeng X, Zou Y, Zheng J, Qiu S, Liu L, Wei C. Quorum sensing-mediated microbial interactions: Mechanisms, applications, challenges and perspectives. Microbiol Res 2023; 273:127414. [PMID: 37236065 DOI: 10.1016/j.micres.2023.127414] [Citation(s) in RCA: 20] [Impact Index Per Article: 20.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2023] [Revised: 05/05/2023] [Accepted: 05/16/2023] [Indexed: 05/28/2023]
Abstract
Microbial community in natural or artificial environments playes critical roles in substance cycles, products synthesis and species evolution. Although microbial community structures have been revealed via culture-dependent and culture-independent approaches, the hidden forces driving the microbial community are rarely systematically discussed. As a mode of cell-to-cell communication that modifies microbial interactions, quorum sensing can regulate biofilm formation, public goods secretion, and antimicrobial substances synthesis, directly or indirectly influencing microbial community to adapt to the changing environment. Therefore, the current review focuses on microbial community in the different habitats from the quorum sensing perspective. Firstly, the definition and classification of quorum sensing were simply introduced. Subsequently, the relationships between quorum sensing and microbial interactions were deeply explored. The latest progressives regarding the applications of quorum sensing in wastewater treatment, human health, food fermentation, and synthetic biology were summarized in detail. Finally, the bottlenecks and outlooks of quorum sensing driving microbial community were adequately discussed. To our knowledge, this current review is the first to reveal the driving force of microbial community from the quorum sensing perspective. Hopefully, this review provides a theoretical basis for developing effective and convenient approaches to control the microbial community with quorum sensing approaches.
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Affiliation(s)
- Xiangyong Zeng
- School of Liquor and Food Engineering, Guizhou University, Guiyang 550025, China; Guizhou Provincial Key Laboratory of Fermentation and Biophomacy, Guizhou University, Guiyang 550025, China.
| | - Yunman Zou
- School of Liquor and Food Engineering, Guizhou University, Guiyang 550025, China; Guizhou Provincial Key Laboratory of Fermentation and Biophomacy, Guizhou University, Guiyang 550025, China
| | - Jia Zheng
- Wuliangye Yibin Co Ltd, No.150 Minjiang West Road, Yibin City 644007, China
| | - Shuyi Qiu
- School of Liquor and Food Engineering, Guizhou University, Guiyang 550025, China; Guizhou Provincial Key Laboratory of Fermentation and Biophomacy, Guizhou University, Guiyang 550025, China
| | - Lanlan Liu
- School of Liquor and Food Engineering, Guizhou University, Guiyang 550025, China; Guizhou Provincial Key Laboratory of Fermentation and Biophomacy, Guizhou University, Guiyang 550025, China
| | - Chaoyang Wei
- School of Liquor and Food Engineering, Guizhou University, Guiyang 550025, China; Guizhou Provincial Key Laboratory of Fermentation and Biophomacy, Guizhou University, Guiyang 550025, China
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Swain A, Pan A. Protein Therapeutic Target Candidates Against Acinetobacter baumannii, a Pathogen of Concern to Planetary Health: A Network-Based Integrative Omics Drug Discovery Approach. OMICS : A JOURNAL OF INTEGRATIVE BIOLOGY 2023; 27:62-74. [PMID: 36735546 DOI: 10.1089/omi.2022.0180] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Acinetobacter baumannii, an opportunistic gram-negative pathogen responsible for several nosocomial infections, has developed resistance to various antibiotics. Proteins involved in the two-component system (TCS), virulence, and antibiotic resistance (AR), help this pathogen in regulating antibiotic susceptibility and virulence mechanisms. The present study reports a network-based integrative omics approach to drug discovery to identify key regulatory proteins as therapeutic candidates against A. baumannii. We collected data on the TCS, virulence, and AR proteins from various databases (P2CS, VFDB, ARDB, and PAIDB), which were subjected to network, host-pathogen, and gene expression data analysis. Network analysis identified 43 hubs, and 10 proteins were found to be interacting with human proteins associated with vital pathways. Of the 53 (43 + 10) pathogen proteins, 46 had no orthologs in the human host. Twelve proteins, namely, RpfC, Wzc, OmpR, EnvZ, BfmS, PilG, histidine kinase, ABC 3 transport family protein, outer membrane porin OprD family, CsuD, Pgm, and LpxA, were differentially expressed in the resistant strain. We propose these proteins as key regulators that warrant evaluation as therapeutic target candidates in the future. Furthermore, structure prediction of ABC 3 transport family protein was performed as a case study. The findings from this study are poised to facilitate and inform drug discovery and development against A. baumannii.
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Affiliation(s)
- Aishwarya Swain
- Department of Bioinformatics, School of Life Sciences, Pondicherry University, Puducherry, India
| | - Archana Pan
- Department of Bioinformatics, School of Life Sciences, Pondicherry University, Puducherry, India
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Feng YM, Long ZQ, Xiang HM, Ran JN, Zhou X, Yang S. Research on Diffusible Signal Factor-Mediated Quorum Sensing in Xanthomonas: A Mini-Review. MOLECULES (BASEL, SWITZERLAND) 2023; 28:molecules28020876. [PMID: 36677934 PMCID: PMC9864630 DOI: 10.3390/molecules28020876] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 12/03/2022] [Revised: 01/10/2023] [Accepted: 01/13/2023] [Indexed: 01/18/2023]
Abstract
Xanthomonas spp. are important plant pathogens that seriously endanger crop yields and food security. RpfF is a key enzyme that is involved in the synthesis of diffusible signal factor (DSF) signals and predominates in the signaling pathway regulating quorum sensing (QS) in Xanthomonas. Currently, novel RpfF enzyme-based quorum sensing agents have been proposed as a promising strategy for the development of new pesticides. However, few reports are available that comprehensively summarize the progress in this field. Therefore, we provide a comprehensive review of the recent advances in DSF-mediated QS and recently reported inhibitors that are proposed as bactericide candidates to target the RpfF enzyme and control plant bacterial diseases.
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Affiliation(s)
- Yu-Mei Feng
- 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
| | - Zhou-Qing Long
- 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
| | - Hong-Mei Xiang
- National Key Laboratory of Green Pesticide, Key Laboratory of Green Pesticide and Agricultural Bioengineering, Ministry of Education, Center for R&D of Fine Chemicals of Guizhou University, Guiyang 550025, China
- School of Chemistry and Chemical Engineering, Qiannan Normal University for Nationalities, Duyun 558000, China
| | - Jun-Ning Ran
- 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
| | - Xiang Zhou
- 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
- Correspondence: or (X.Z.); or (S.Y.)
| | - Song Yang
- 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
- Correspondence: or (X.Z.); or (S.Y.)
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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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The Wsp chemosensory system modulates c-di-GMP-dependent biofilm formation by integrating DSF quorum sensing through the WspR-RpfG complex in Lysobacter. NPJ Biofilms Microbiomes 2022; 8:97. [PMID: 36526637 PMCID: PMC9758175 DOI: 10.1038/s41522-022-00365-1] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2022] [Accepted: 12/06/2022] [Indexed: 12/23/2022] Open
Abstract
The ubiquitous Wsp (wrinkly spreader phenotype) chemosensory system and DSF (diffusible signal factor) quorum sensing are two important chemically associated signaling systems that mediate bacterial communications between the host and environment. Although these two systems individually control biofilm formation in pathogenic bacteria via the ubiquitous second messenger c-di-GMP, their crosstalk mechanisms remain elusive. Here we present a scenario from the plant-beneficial and antifungal bacterium Lysobacter enzymogenes OH11, where biofilm formation favors the colonization of this bacterium in fungal hyphae. We found that the Wsp system regulated biofilm formation via WspR-mediated c-di-GMP signaling, whereas DSF system did not depend on the enzymatic activity of RpfG to regulate biofilm formation. We further found that WspR, a diguanylate cyclase (DGC) responsible for c-di-GMP synthesis, could directly bind to one of the DSF signaling components, RpfG, an active phosphodiesterase (PDE) responsible for c-di-GMP degradation. Thus, the WspR-RpfG complex represents a previously undiscovered molecular linker connecting the Wsp and DSF systems. Mechanistically, RpfG could function as an adaptor protein to bind and inhibit the DGC activity of unphosphorylated WspR independent of its PDE activity. Phosphorylation of WspR impaired its binding affinity to RpfG and also blocked the ability of RpfG to act as an adaptor protein, which enabled the Wsp system to regulate biofilm formation in a c-di-GMP-dependent manner by dynamically integrating the DSF system. Our findings demonstrated a previously uncharacterized mechanism of crosstalk between Wsp and DSF systems in plant-beneficial and antifungal bacteria.
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Liu Y, Gao J, Wang N, Li X, Fang N, Zhuang X. Diffusible signal factor enhances the saline-alkaline resistance and rhizosphere colonization of Stenotrophomonas rhizophila by coordinating optimal metabolism. THE SCIENCE OF THE TOTAL ENVIRONMENT 2022; 834:155403. [PMID: 35469877 DOI: 10.1016/j.scitotenv.2022.155403] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/02/2022] [Revised: 04/15/2022] [Accepted: 04/16/2022] [Indexed: 06/14/2023]
Abstract
Quorum sensing (QS) regulates various physiological processes in a cell density-dependent mode via cell-cell communication. Stenotrophomonas rhizophila DSM14405T having the diffusible signal factor (DSF)-QS system, is a plant growth-promoting rhizobacteria (PGPR) that enables host plants to tolerate saline-alkaline stress. However, the regulatory mechanism of DSF-QS in S. rhizophila is not fully understood. In this study, we used S. rhizophila DSM14405T wild-type (WT) and an incompetent DSF production rpfF-knockout mutant to explore the regulatory role of QS in S. rhizophila growth, stress responses, biofilm formation, and colonization under saline-alkaline stress. We found that a lack of DSF-QS reduces the tolerance of S. rhizosphere ΔrpfF to saline-alkaline stress, with a nearly 25-fold reduction in the ΔrpfF population compared with WT at 24 h under stress. Transcriptome analysis revealed that QS helps S. rhizophila WT respond to saline-alkaline stress by enhancing metabolism associated with the cell wall and membrane, oxidative stress response, cell adhesion, secretion systems, efflux pumps, and TonB systems. These metabolic systems enhance penetration defense, Na+ efflux, iron uptake, and reactive oxygen species scavenging. Additionally, the absence of DSF-QS causes overexpression of biofilm-associated genes under the regulation of sigma 54 and other transcriptional regulators. However, greater biofilm formation capacity confers no advantage on S. rhizosphere ΔrpfF in rhizosphere colonization. Altogether, our results show the importance of QS in PGPR growth and colonization; QS gives PGPR a collective adaptive advantage in harsh natural environments.
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Affiliation(s)
- Ying Liu
- CAS Key Laboratory of Environment Biotechnology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China; School of Life Sciences, Life Sciences and Medicine, University of Science and Technology of China, Hefei 230026, China
| | - Jie Gao
- CAS Key Laboratory of Environment Biotechnology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China; College of Resources and Environment, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Na Wang
- CAS Key Laboratory of Environment Biotechnology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China; College of Resources and Environment, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Xianglong Li
- CAS Key Laboratory of Environment Biotechnology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China; College of Resources and Environment, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Na Fang
- CAS Key Laboratory of Environment Biotechnology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China; Institute of International Rivers and Eco-security, Yunan University, Kunming 650500, China
| | - Xuliang Zhuang
- CAS Key Laboratory of Environment Biotechnology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China; College of Resources and Environment, University of Chinese Academy of Sciences, Beijing 100049, China; Institute of Tibetan Plateau Research, Chinese Academy of Sciences, Beijing 100101, China.
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11
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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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12
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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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13
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The cis-2-dodecenoic acid (BDSF) quorum sensing system in Burkholderia cenocepacia. Appl Environ Microbiol 2022; 88:e0234221. [PMID: 34985987 DOI: 10.1128/aem.02342-21] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
It has been demonstrated that quorum sensing (QS) is widely employed by bacterial cells to coordinately regulate various group behaviors. Diffusible signal factor (DSF)-type signals have emerged as a growing family of conserved cell-cell communication signals. In addition to the DSF signal initially identified in Xanthomonas campestris pv. campestris, Burkholderia diffusible signal factor (BDSF, cis-2-dodecenoic acid) has been recognized as a conserved DSF-type signal with specific characteristics in both signal perception and transduction from DSF signals. Here, we review the history and current progress of the research of this type of signal, especially focusing on its biosynthesis, signaling pathways, and biological functions. We also discuss and explore the huge potential of targeting this kind of QS system as a new therapeutic strategy to control bacterial infections and diseases.
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14
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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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15
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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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16
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Diffusible Signal Factors Act through AraC-Type Transcriptional Regulators as Chemical Cues To Repress Virulence of Enteric Pathogens. Infect Immun 2020; 88:IAI.00226-20. [PMID: 32690633 PMCID: PMC7504960 DOI: 10.1128/iai.00226-20] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2020] [Accepted: 07/08/2020] [Indexed: 01/02/2023] Open
Abstract
Successful colonization by enteric pathogens is contingent upon effective interactions with the host and the resident microbiota. These pathogens thus respond to and integrate myriad signals to control virulence. Long-chain fatty acids repress the virulence of the important enteric pathogens Salmonella enterica and Vibrio cholerae by repressing AraC-type transcriptional regulators in pathogenicity islands. While several fatty acids are known to be repressive, we show here that cis-2-unsaturated fatty acids, a rare chemical class used as diffusible signal factors (DSFs), are highly potent inhibitors of virulence functions. We found that DSFs repressed virulence gene expression of enteric pathogens by interacting with transcriptional regulators of the AraC family. In Salmonella enterica serovar Typhimurium, DSFs repress the activity of HilD, an AraC-type activator essential to the induction of epithelial cell invasion, by both preventing its interaction with target DNA and inducing its rapid degradation by Lon protease. cis-2-Hexadecenoic acid (c2-HDA), a DSF produced by Xylella fastidiosa, was the most potent among those tested, repressing the HilD-dependent transcriptional regulator hilA and the type III secretion effector sopB >200- and 68-fold, respectively. Further, c2-HDA attenuated the transcription of the ToxT-dependent cholera toxin synthesis genes of V. cholerae c2-HDA significantly repressed invasion gene expression by Salmonella in the murine colitis model, indicating that the HilD-dependent signaling pathway functions within the complex milieu of the animal intestine. These data argue that enteric pathogens respond to DSFs as interspecies signals to identify appropriate niches in the gut for virulence activation, which could be exploited to control the virulence of enteric pathogens.
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17
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Feng Q, Ahator SD, Zhou T, Liu Z, Lin Q, Liu Y, Huang J, Zhou J, Zhang LH. Regulation of Exopolysaccharide Production by ProE, a Cyclic-Di-GMP Phosphodiesterase in Pseudomonas aeruginosa PAO1. Front Microbiol 2020; 11:1226. [PMID: 32582123 PMCID: PMC7290235 DOI: 10.3389/fmicb.2020.01226] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2020] [Accepted: 05/14/2020] [Indexed: 11/13/2022] Open
Abstract
The ubiquitous second messenger c-di-GMP is involved in regulation of multiple biological functions including the important extracellular matrix exopolysaccharides (EPS). But how c-di-GMP metabolic proteins influence EPS and their enzymatic properties are not fully understood. Here we showed that deletion of proE, which encodes a protein with GGDEF-EAL hybrid domains, significantly increased the transcriptional expression of the genes encoding EPS production in Pseudomonas aeruginosa PAO1 and changed the bacterial colony morphology. Our data showed that ProE is a very active phosphodiesterase (PDE), with a high enzyme activity in degradation of c-di-GMP. Interestingly, the optimal activity of ProE was found in the presence of Co2+, unlike other PDEs that commonly rely on Mg2+ or Mn2+ for best performance. Furthermore, we identified three widely conserved novel residues that are critical for the function of ProE through site-directed mutagenesis. Subsequent study showed that ProE, together with other three key PDEs, i.e., RbdA, BifA, and DipA regulate the EPS production in P. aeruginosa PAO1. Moreover, by using the GFP-fusion approach, we observed that these four EPS associated-PDEs showed a polar localization pattern in general. Taken together, our data unveil the molecular mechanisms of ProE in regulation of EPS production, and provide a new insight on its enzymatic properties in degradation of c-di-GMP.
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Affiliation(s)
- Qishun Feng
- 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, South China Agricultural University, Guangzhou, China
| | - Stephen Dela Ahator
- 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, South China Agricultural University, Guangzhou, China
| | - Tian Zhou
- 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, South China Agricultural University, Guangzhou, China
| | - Zhiqing Liu
- 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, South China Agricultural University, Guangzhou, China
| | - Qiqi Lin
- 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, South China Agricultural University, Guangzhou, China
| | - Yang Liu
- 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, South China Agricultural University, Guangzhou, China
| | - Jiahui Huang
- 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, South China Agricultural University, Guangzhou, China
| | - Jianuan Zhou
- 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, South China Agricultural University, Guangzhou, China
| | - Lian-Hui Zhang
- 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, South China Agricultural University, Guangzhou, China
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18
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Li R, Wang X, Wu L, Huang L, Qin Q, Yao J, Lu G, Tang J. Xanthomonas campestris sensor kinase HpaS co-opts the orphan response regulator VemR to form a branched two-component system that regulates motility. MOLECULAR PLANT PATHOLOGY 2020; 21:360-375. [PMID: 31919999 PMCID: PMC7036368 DOI: 10.1111/mpp.12901] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/05/2019] [Revised: 11/26/2019] [Accepted: 12/04/2019] [Indexed: 05/07/2023]
Abstract
Xanthomonas campestris pv. campestris (Xcc) controls virulence and plant infection mechanisms via the activity of the sensor kinase and response regulator pair HpaS/hypersensitive response and pathogenicity G (HrpG). Detailed analysis of the regulatory role of HpaS has suggested the occurrence of further regulators besides HrpG. Here we used in vitro and in vivo approaches to identify the orphan response regulator VemR as another partner of HpaS and to characterize relevant interactions between components of this signalling system. Bacterial two-hybrid and protein pull-down assays revealed that HpaS physically interacts with VemR. Phos-tag SDS-PAGE analysis showed that mutation in hpaS reduced markedly the phosphorylation of VemR in vivo. Mutation analysis reveals that HpaS and VemR contribute to the regulation of motility and this relationship appears to be epistatic. Additionally, we show that VemR control of Xcc motility is due in part to its ability to interact and bind to the flagellum rotor protein FliM. Taken together, the findings describe the unrecognized regulatory role of sensor kinase HpaS and orphan response regulator VemR in the control of motility in Xcc and contribute to the understanding of the complex regulatory mechanisms used by Xcc during plant infection.
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Affiliation(s)
- Rui‐Fang Li
- State Key Laboratory for Conservation and Utilization of Subtropical Agro‐bioresourcesCollege of Life Science and TechnologyGuangxi UniversityNanningChina
- Guangxi Key Laboratory of Biology for Crop Diseases and Insect PestsPlant Protection Research InstituteGuangxi Academy of Agricultural SciencesNanningChina
| | - Xin‐Xin Wang
- State Key Laboratory for Conservation and Utilization of Subtropical Agro‐bioresourcesCollege of Life Science and TechnologyGuangxi UniversityNanningChina
| | - Liu Wu
- State Key Laboratory for Conservation and Utilization of Subtropical Agro‐bioresourcesCollege of Life Science and TechnologyGuangxi UniversityNanningChina
| | - Li Huang
- State Key Laboratory for Conservation and Utilization of Subtropical Agro‐bioresourcesCollege of Life Science and TechnologyGuangxi UniversityNanningChina
| | - Qi‐Jian Qin
- State Key Laboratory for Conservation and Utilization of Subtropical Agro‐bioresourcesCollege of Life Science and TechnologyGuangxi UniversityNanningChina
| | - Jia‐Li Yao
- State Key Laboratory for Conservation and Utilization of Subtropical Agro‐bioresourcesCollege of Life Science and TechnologyGuangxi UniversityNanningChina
| | - Guang‐Tao Lu
- State Key Laboratory for Conservation and Utilization of Subtropical Agro‐bioresourcesCollege of Life Science and TechnologyGuangxi UniversityNanningChina
| | - Ji‐Liang Tang
- State Key Laboratory for Conservation and Utilization of Subtropical Agro‐bioresourcesCollege of Life Science and TechnologyGuangxi UniversityNanningChina
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19
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Wang FF, Qian W. The roles of histidine kinases in sensing host plant and cell-cell communication signal in a phytopathogenic bacterium. Philos Trans R Soc Lond B Biol Sci 2020; 374:20180311. [PMID: 30967026 DOI: 10.1098/rstb.2018.0311] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023] Open
Abstract
It has long been known that phytopathogenic bacteria react to plant-specific stimuli or environmental factors. However, how bacterial cells sense these environmental cues remains incompletely studied. Recently, three kinds of histidine kinases (HKs) were identified as receptors to perceive plant-associated or quorum-sensing signals. Among these kinases, HK VgrS detects iron depletion by binding to ferric iron via an ExxE motif, RpfC binds diffusible signal factor (DSF) by its N-terminal peptide and activates its autokinase activity through relaxation of autoinhibition, and PcrK specifically senses plant hormone-cytokinin and elicits bacterial responses to oxidative stress. These HKs are critical sensors that regulate the virulence of a Gram-negative bacterium, Xanthomonas campestris pv. campestris. Research progress on the signal perception of phytopathogenic bacterial HKs suggests that inter-kingdom signalling between host plants and pathogens controls pathogenesis and can be used as a potential molecular target to protect plants from bacterial diseases. This article is part of the theme issue 'Biotic signalling sheds light on smart pest management'.
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Affiliation(s)
- Fang-Fang Wang
- State Key Laboratory of Plant Genomics, Institute of Microbiology, Chinese Academy of Sciences , Beijing 100101 , People's Republic of China
| | - Wei Qian
- State Key Laboratory of Plant Genomics, Institute of Microbiology, Chinese Academy of Sciences , Beijing 100101 , People's Republic of China
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20
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Modulation of Quorum Sensing as an Adaptation to Nodule Cell Infection during Experimental Evolution of Legume Symbionts. mBio 2020; 11:mBio.03129-19. [PMID: 31992622 PMCID: PMC6989110 DOI: 10.1128/mbio.03129-19] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Over millions of years, changes have occurred in regulatory circuitries in response to genome reorganization and/or persistent changes in environmental conditions. How bacteria optimize regulatory circuitries is crucial to understand bacterial adaptation. Here, we analyzed the experimental evolution of the plant pathogen Ralstonia solanacearum into legume symbionts after the transfer of a natural plasmid encoding the essential mutualistic genes. We showed that the Phc quorum sensing system required for the virulence of the ancestral bacterium was reconfigured to improve intracellular infection of root nodules induced by evolved Ralstonia A single mutation in either the PhcB autoinducer synthase or the PhcQ regulator of the sensory cascade tuned the kinetics of activation of the central regulator PhcA in response to cell density so that the minimal stimulatory concentration of autoinducers needed for a given response was increased. Yet, a change in the expression of a PhcA target gene was observed in infection threads progressing in root hairs, suggesting early programming for the late accommodation of bacteria in nodule cells. Moreover, this delayed switch to the quorum sensing mode decreased the pathogenicity of the ancestral strain, illustrating the functional plasticity of regulatory systems and showing how a small modulation in signal response can produce drastic changes in bacterial lifestyle.IMPORTANCE Rhizobia are soil bacteria from unrelated genera able to form a mutualistic relationship with legumes. Bacteria induce the formation of root nodules, invade nodule cells, and fix nitrogen to the benefit of the plant. Rhizobial lineages emerged from the horizontal transfer of essential symbiotic genes followed by genome remodeling to activate and/or optimize the acquired symbiotic potential. This evolutionary scenario was replayed in a laboratory evolution experiment in which the plant pathogen Ralstonia solanacearum successively evolved the capacities to nodulate Mimosa pudica and poorly invade, then massively invade, nodule cells. In some lines, the improvement of intracellular infection was achieved by mutations modulating a quorum sensing regulatory system of the ancestral strain. This modulation that affects the activity of a central regulator during the earliest stages of symbiosis has a huge impact on late stages of symbiosis. This work showed that regulatory rewiring is the main driver of this pathogeny-symbiosis transition.
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21
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Ling J, Zhou L, Wu G, Zhao Y, Jiang T, Liu F. The AHL Quorum-Sensing System Negatively Regulates Growth and Autolysis in Lysobacter brunescens. Front Microbiol 2019; 10:2748. [PMID: 31849892 PMCID: PMC6902743 DOI: 10.3389/fmicb.2019.02748] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2019] [Accepted: 11/12/2019] [Indexed: 11/13/2022] Open
Abstract
Lysobacter species are emerging as novel sources of antibiotics, but the regulation of their physiological metabolism is still poorly understood. In this work, we extracted AHL (acyl-homoserine lactone) autoinducers, identified the structures of AHLs and described the AHL quorum-sensing system in Lysobacter brunescens OH23. AHLs were isolated from the supernatant of L. brunescens OH23, and ESI-MS/MS (electrospray ionization mass spectrometry) analysis revealed biosynthesis of three different AHL chemical structures by L. brunescens OH23: N-(3-oxohexanoyl)- homoserine lactone (HSL), 3-OH-C10-HSL and C8-HSL. The growth rate of AHL quorum-sensing knockout mutants was dramatically increased compared to that of wildtype. Sucrose consumptions were also twice as high in AHL quorum-sensing knockout mutants than that in wildtype in early-log phase. Additionally, expression of key genes related to sucrose metabolism α-glucosidase was enhanced in AHL quorum-sensing knockout mutants, which indicated that AHL quorum sensing negatively regulates sucrose uptake and metabolism which further affects the growth rate of L. brunescens. Furthermore, autolysis was strongly induced in AHL quorum-sensing knockout mutants compared to wildtype, suggesting that AHL quorum sensing plays a negative regulatory role in cell autolysis. Moreover, compared to wildtype, XSAC (Xanthomonas-specific antibiotic compound) production was significantly increased in AHL knockout mutants in the early-log and late-log phases, and surface motility capabilities are also enhanced also in AHL knockout mutants; the normalized data of XSAC production and surface motility and expressions of key genes related to these two phenotypes reveal that growth rare and autolysis strongly affects XSAC biosynthesis and surface motility rather than AHL quorum-sensing system. Our results show that the AHL quorum-sensing system negatively regulates cell growth and autolysis, and further maintain nutrition homeostasis and population stability in L. brunescens.
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Affiliation(s)
- Jun Ling
- Jiangsu Key Laboratory for Food Quality and Safety, State Key Laboratory Cultivation Base of Ministry of Science and Technology, Institute of Plant Protection, Jiangsu Academy of Agricultural Sciences, Nanjing, China
| | - Lan Zhou
- Academy of Agricultural Sciences of Yanbian, Longjing, China
| | - Guichun Wu
- Jiangsu Key Laboratory for Food Quality and Safety, State Key Laboratory Cultivation Base of Ministry of Science and Technology, Institute of Plant Protection, Jiangsu Academy of Agricultural Sciences, Nanjing, China
| | - Yancun Zhao
- Jiangsu Key Laboratory for Food Quality and Safety, State Key Laboratory Cultivation Base of Ministry of Science and Technology, Institute of Plant Protection, Jiangsu Academy of Agricultural Sciences, Nanjing, China
| | - Tianping Jiang
- Jiangsu Key Laboratory for Food Quality and Safety, State Key Laboratory Cultivation Base of Ministry of Science and Technology, Institute of Plant Protection, Jiangsu Academy of Agricultural Sciences, Nanjing, China
| | - Fengquan Liu
- Jiangsu Key Laboratory for Food Quality and Safety, State Key Laboratory Cultivation Base of Ministry of Science and Technology, Institute of Plant Protection, Jiangsu Academy of Agricultural Sciences, Nanjing, China.,School of the Environment and Safety Engineering, Jiangsu University, Zhenjiang, China
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22
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Yu Y, Ma J, Guo Q, Ma J, Wang H. A novel 3-oxoacyl-ACP reductase (FabG3) is involved in the xanthomonadin biosynthesis of Xanthomonas campestris pv. campestris. MOLECULAR PLANT PATHOLOGY 2019; 20:1696-1709. [PMID: 31560825 PMCID: PMC6859482 DOI: 10.1111/mpp.12871] [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: 05/10/2023]
Abstract
Xanthomonas campestris pv. campestris (Xcc), the causal agent of black rot in crucifers, produces a membrane-bound yellow pigment called xanthomonadin to protect against photobiological and peroxidative damage, and uses a quorum-sensing mechanism mediated by the diffusible signal factor (DSF) family signals to regulate virulence factors production. The Xcc gene XCC4003, annotated as Xcc fabG3, is located in the pig cluster, which may be responsible for xanthomonadin synthesis. We report that fabG3 expression restored the growth of the Escherichia coli fabG temperature-sensitive mutant CL104 under non-permissive conditions. In vitro assays demonstrated that FabG3 catalyses the reduction of 3-oxoacyl-acyl carrier protein (ACP) intermediates in fatty acid synthetic reactions, although FabG3 had a lower activity than FabG1. Moreover, the fabG3 deletion did not affect growth or fatty acid composition. These results indicate that Xcc fabG3 encodes a 3-oxoacyl-ACP reductase, but is not essential for growth or fatty acid synthesis. However, the Xcc fabG3 knock-out mutant abolished xanthomonadin production, which could be only restored by wild-type fabG3, but not by other 3-oxoacyl-ACP reductase-encoding genes, indicating that Xcc FabG3 is specifically involved in xanthomonadin biosynthesis. Additionally, our study also shows that the Xcc fabG3-disrupted mutant affects Xcc virulence in host plants.
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Affiliation(s)
- Yonghong Yu
- Guangdong Food and Drug Vocational CollegeGuangzhouGuangdong510520China
- Guangdong Provincial Key Laboratory of Protein Function and Regulation in Agricultural OrganismsCollege of Life SciencesSouth China Agricultural UniversityGuangzhouGuangdong510642China
| | - Jianrong Ma
- Guangdong Food and Drug Vocational CollegeGuangzhouGuangdong510520China
| | - Qiaoqiao Guo
- Guangdong Provincial Key Laboratory of Protein Function and Regulation in Agricultural OrganismsCollege of Life SciencesSouth China Agricultural UniversityGuangzhouGuangdong510642China
| | - Jincheng Ma
- Guangdong Provincial Key Laboratory of Protein Function and Regulation in Agricultural OrganismsCollege of Life SciencesSouth China Agricultural UniversityGuangzhouGuangdong510642China
| | - Haihong Wang
- Guangdong Provincial Key Laboratory of Protein Function and Regulation in Agricultural OrganismsCollege of Life SciencesSouth China Agricultural UniversityGuangzhouGuangdong510642China
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23
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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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24
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Bhagirath AY, Li Y, Patidar R, Yerex K, Ma X, Kumar A, Duan K. Two Component Regulatory Systems and Antibiotic Resistance in Gram-Negative Pathogens. Int J Mol Sci 2019; 20:E1781. [PMID: 30974906 PMCID: PMC6480566 DOI: 10.3390/ijms20071781] [Citation(s) in RCA: 83] [Impact Index Per Article: 16.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2019] [Revised: 04/05/2019] [Accepted: 04/08/2019] [Indexed: 12/17/2022] Open
Abstract
Gram-negative pathogens such as Klebsiella pneumoniae, Acinetobacter baumannii, and Pseudomonas aeruginosa are the leading cause of nosocomial infections throughout the world. One commonality shared among these pathogens is their ubiquitous presence, robust host-colonization and most importantly, resistance to antibiotics. A significant number of two-component systems (TCSs) exist in these pathogens, which are involved in regulation of gene expression in response to environmental signals such as antibiotic exposure. While the development of antimicrobial resistance is a complex phenomenon, it has been shown that TCSs are involved in sensing antibiotics and regulating genes associated with antibiotic resistance. In this review, we aim to interpret current knowledge about the signaling mechanisms of TCSs in these three pathogenic bacteria. We further attempt to answer questions about the role of TCSs in antimicrobial resistance. We will also briefly discuss how specific two-component systems present in K. pneumoniae, A. baumannii, and P. aeruginosa may serve as potential therapeutic targets.
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Affiliation(s)
- Anjali Y Bhagirath
- Department of Oral Biology, Rady Faculty of Health Sciences, University of Manitoba, 780 Bannatyne Ave, Winnipeg, MB R3E 0J9, Canada.
| | - Yanqi Li
- Department of Oral Biology, Rady Faculty of Health Sciences, University of Manitoba, 780 Bannatyne Ave, Winnipeg, MB R3E 0J9, Canada.
| | - Rakesh Patidar
- Department of Microbiology, Faculty of Sciences, University of Manitoba, Winnipeg, MB R3E 0J9, Canada.
| | - Katherine Yerex
- Department of Oral Biology, Rady Faculty of Health Sciences, University of Manitoba, 780 Bannatyne Ave, Winnipeg, MB R3E 0J9, Canada.
| | - Xiaoxue Ma
- Department of Oral Biology, Rady Faculty of Health Sciences, University of Manitoba, 780 Bannatyne Ave, Winnipeg, MB R3E 0J9, Canada.
| | - Ayush Kumar
- Department of Microbiology, Faculty of Sciences, University of Manitoba, Winnipeg, MB R3E 0J9, Canada.
| | - Kangmin Duan
- Department of Oral Biology, Rady Faculty of Health Sciences, University of Manitoba, 780 Bannatyne Ave, Winnipeg, MB R3E 0J9, Canada.
- Department of Medical Microbiology & Infectious Diseases, Rady Faculty of Health Sciences, University of Manitoba, 780 Bannatyne Ave, Winnipeg, MB R3E 0J9, Canada.
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25
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Zhang C, Lv M, Yin W, Dong T, Chang C, Miao Y, Jia Y, Deng Y. Xanthomonas campestris Promotes Diffusible Signal Factor Biosynthesis and Pathogenicity by Utilizing Glucose and Sucrose from Host Plants. MOLECULAR PLANT-MICROBE INTERACTIONS : MPMI 2019; 32:157-166. [PMID: 30156480 DOI: 10.1094/mpmi-07-18-0187-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: 06/08/2023]
Abstract
The plant pathogen Xanthomonas campestris pv. campestris produces diffusible signal factor (DSF) quorum sensing (QS) signals to regulate its biological functions and virulence. Our previous study showed that X. campestris pv. campestris utilizes host plant metabolites to enhance the biosynthesis of DSF family signals. However, it is unclear how X. campestris pv. campestris benefits from the metabolic products of the host plant. In this study, we observed that the host plant metabolites not only boosted the production of the DSF family signals but also modulated the expression levels of DSF-regulated genes in X. campestris pv. campestris. Infection with X. campestris pv. campestris induced changes in the expression of many sugar transporter genes in Arabidopsis thaliana. Exogenous addition of sucrose or glucose, which are the major products of photosynthesis in plants, enhanced DSF signal production and X. campestris pv. campestris pathogenicity in the Arabidopsis model. In addition, several sucrose hydrolase-encoding genes in X. campestris pv. campestris and sucrose invertase-encoding genes in the host plant were notably upregulated during the infection process. These enzymes hydrolyzed sucrose to glucose and fructose, and in trans expression of one of these enzymes, CINV1 of A. thaliana or XC_0805 of X. campestris pv. campestris, enhanced DSF signal biosynthesis in X. campestris pv. campestris in the presence of sucrose. Taken together, our findings demonstrate that X. campestris pv. campestris applies multiple strategies to utilize host plant sugars to enhance QS and pathogenicity.
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Affiliation(s)
- Chunyan Zhang
- 1 State Key Laboratory for Conservation and Utilization of Subtropical Agro-Bioresources, South China Agricultural University, Guangzhou 510642, China
- 2 Guangdong Innovative Research Team of Sociomicrobiology, College of Agriculture, South China Agricultural University
| | - Mingfa Lv
- 3 Integrative Microbiology Research Centre, South China Agricultural University
| | - Wenfang Yin
- 1 State Key Laboratory for Conservation and Utilization of Subtropical Agro-Bioresources, South China Agricultural University, Guangzhou 510642, China
- 2 Guangdong Innovative Research Team of Sociomicrobiology, College of Agriculture, South China Agricultural University
| | - Tingyan Dong
- 1 State Key Laboratory for Conservation and Utilization of Subtropical Agro-Bioresources, South China Agricultural University, Guangzhou 510642, China
- 2 Guangdong Innovative Research Team of Sociomicrobiology, College of Agriculture, South China Agricultural University
| | - Changqing Chang
- 2 Guangdong Innovative Research Team of Sociomicrobiology, College of Agriculture, South China Agricultural University
- 3 Integrative Microbiology Research Centre, South China Agricultural University
| | - Yansong Miao
- 4 School of Biological Sciences, Nanyang Technological University, Singapore 637551; and
| | - Yantao Jia
- 5 State Key Laboratory of Plant Genomics, Institute of Microbiology, Chinese Academy of Sciences, Beijing 100101, China
| | - Yinyue Deng
- 1 State Key Laboratory for Conservation and Utilization of Subtropical Agro-Bioresources, South China Agricultural University, Guangzhou 510642, China
- 2 Guangdong Innovative Research Team of Sociomicrobiology, College of Agriculture, South China Agricultural University
- 3 Integrative Microbiology Research Centre, South China Agricultural University
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26
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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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27
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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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28
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Cui C, Yang C, Song S, Fu S, Sun X, Yang L, He F, Zhang LH, Zhang Y, Deng Y. A novel two-component system modulates quorum sensing and pathogenicity in Burkholderia cenocepacia. Mol Microbiol 2018; 108:32-44. [PMID: 29363827 DOI: 10.1111/mmi.13915] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2017] [Revised: 01/11/2018] [Accepted: 01/21/2018] [Indexed: 01/01/2023]
Abstract
Quorum sensing (QS) is widely utilized by bacterial pathogens to regulate biological functions and pathogenicity. Recent evidence has shown that QS is subject to regulatory cascades, especially two-component systems that often respond to environmental stimulation. At least two different types of QS systems regulate pathogenesis in Burkholderia cenocepacia. However, it remains unclear how this bacterial pathogen controls these QS systems. Here, we demonstrate a novel two-component system RqpSR (Regulating Quorum sensing and Pathogenicity), which plays an important role in modulating QS and pathogenesis in B. cenocepacia. We demonstrate strong protein-protein binding affinity between RqpS and RqpR. Mutations in rqpS and rqpR exerted overlapping effects on B. cenocepacia transcriptomes and phenotypes, including motility, biofilm formation and virulence. In trans expression of rqpR rescued the defective phenotypes in the rqpS mutant. RqpR controls target gene expression by direct binding to DNA promoters, including the cis-2-dodecenoic acid (BDSF) and N-acylhomoserine lactone (AHL) signal synthase gene promoters. These findings suggest that the RqpSR system strongly modulates physiology by forming a complicated hierarchy with QS systems. This type of two-component system appears to be widely distributed and coexists with the BDSF QS system in various bacterial species.
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Affiliation(s)
- Chaoyu Cui
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-Bioresources, South China Agricultural University, Guangzhou 510642, China.,Guangdong Innovative Research Team of Sociomicrobiology, College of Agriculture, South China Agricultural University, Guangzhou 510642, China.,Integrative Microbiology Research Centre, South China Agricultural University, Guangzhou 510642, China.,Department of Microbiology and Immunology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore 117597, Singapore
| | - Chunxi Yang
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-Bioresources, South China Agricultural University, Guangzhou 510642, China.,Guangdong Innovative Research Team of Sociomicrobiology, College of Agriculture, South China Agricultural University, Guangzhou 510642, China
| | - Shihao Song
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-Bioresources, South China Agricultural University, Guangzhou 510642, China.,Guangdong Innovative Research Team of Sociomicrobiology, College of Agriculture, South China Agricultural University, Guangzhou 510642, China
| | - Shuna Fu
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-Bioresources, South China Agricultural University, Guangzhou 510642, China.,Guangdong Innovative Research Team of Sociomicrobiology, College of Agriculture, South China Agricultural University, Guangzhou 510642, China
| | - Xiuyun Sun
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-Bioresources, South China Agricultural University, Guangzhou 510642, China.,Guangdong Innovative Research Team of Sociomicrobiology, College of Agriculture, South China Agricultural University, Guangzhou 510642, China
| | - Liang Yang
- Singapore Centre for Environmental Life Sciences Engineering (SCELSE), Nanyang Technological University, Singapore 637551, Singapore
| | - Fei He
- Integrative Microbiology Research Centre, South China Agricultural University, Guangzhou 510642, China
| | - Lian-Hui Zhang
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-Bioresources, South China Agricultural University, Guangzhou 510642, China.,Integrative Microbiology Research Centre, South China Agricultural University, Guangzhou 510642, China
| | - Yongliang Zhang
- Department of Microbiology and Immunology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore 117597, Singapore
| | - Yinyue Deng
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-Bioresources, South China Agricultural University, Guangzhou 510642, China.,Guangdong Innovative Research Team of Sociomicrobiology, College of Agriculture, South China Agricultural University, Guangzhou 510642, China.,Integrative Microbiology Research Centre, South China Agricultural University, Guangzhou 510642, China
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29
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Burkholderia cenocepacia integrates cis-2-dodecenoic acid and cyclic dimeric guanosine monophosphate signals to control virulence. Proc Natl Acad Sci U S A 2017; 114:13006-13011. [PMID: 29158389 DOI: 10.1073/pnas.1709048114] [Citation(s) in RCA: 45] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
Quorum sensing (QS) signals are used by bacteria to regulate biological functions in response to cell population densities. Cyclic diguanosine monophosphate (c-di-GMP) regulates cell functions in response to diverse environmental chemical and physical signals that bacteria perceive. In Burkholderia cenocepacia, the QS signal receptor RpfR degrades intracellular c-di-GMP when it senses the QS signal cis-2-dodecenoic acid, also called Burkholderia diffusible signal factor (BDSF), as a proxy for high cell density. However, it was unclear how this resulted in control of BDSF-regulated phenotypes. Here, we found that RpfR forms a complex with a regulator named GtrR (BCAL1536) to enhance its binding to target gene promoters under circumstances where the BDSF signal binds to RpfR to stimulate its c-di-GMP phosphodiesterase activity. In the absence of BDSF, c-di-GMP binds to the RpfR-GtrR complex and inhibits its ability to control gene expression. Mutations in rpfR and gtrR had overlapping effects on both the B. cenocepacia transcriptome and BDSF-regulated phenotypes, including motility, biofilm formation, and virulence. These results show that RpfR is a QS signal receptor that also functions as a c-di-GMP sensor. This protein thus allows B. cenocepacia to integrate information about its physical and chemical surroundings as well as its population density to control diverse biological functions including virulence. This type of QS system appears to be widely distributed in beta and gamma proteobacteria.
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30
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Xu H, Wang R, Zhao Y, Fu ZQ, Qian G, Liu F. LesR is a novel upstream regulator that controls downstream Clp expression to modulate antibiotic HSAF biosynthesis and cell aggregation in Lysobacter enzymogenes OH11. Microb Cell Fact 2017; 16:202. [PMID: 29137648 PMCID: PMC5686890 DOI: 10.1186/s12934-017-0818-2] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2017] [Accepted: 11/09/2017] [Indexed: 01/29/2023] Open
Abstract
BACKGROUND Heat-stable antifungal factor (HSAF) is a polycyclic tetramate macrolactam secondary metabolite that exhibits broad-spectrum inhibitory activities against filamentous fungal pathogens. The native yield of this chemical is low. It is also a great challenge to synthesize HSAF artificially, due to its complex structure. Understanding the regulatory mechanism underlying HSAF biosynthesis could provide genetic basis for engineering high HSAF-producing strain. The transcription factor Clp is a global regulator that controls bacterial pathogenicity and the expression of one hundred related genes in the phytopathogenic bacterium Xanthomonas campestris pv. campestris (Xcc). Diffusible signal factor (DSF) chemical signaling is the only well-characterized upstream regulatory pathway that involves downstream Clp regulation in Xcc. Such a regulatory hierarchy between DSF signaling and Clp is also conserved in the Gram-negative biological control agent Lysobacter enzymogenes, where the DSF signaling system controls antifungal antibiotic HSAF biosynthesis via Clp. RESULTS Here, using LLysobacter enzymogenes OH11 as a working organism, we examined a novel upstream regulator, LesR, a LuxR solo that controls Clp expression to modulate HSAF biosynthesis as well as cell aggregation. We found that the overexpression of lesR in strain OH11 almost entirely shut down HSAF production and accelerated cell aggregation. These changed phenotypes could be rescued by the introduction of plasmid-borne clp in the lesR overexpression background. Consistent with findings, we further found that overexpression of lesR led to a decrease in the Clp level. CONCLUSIONS These results collectively have shown that LesR could exert its function, i.e., HSAF biosynthesis, via downstream Clp. These findings were subsequently validated by a comparative transcriptome analysis, where the regulatory action of LesR was found to largely overlap with that of Clp. Therefore, in addition to the well-known DSF signaling system, the present study reveals that LesR functions as a new upstream regulatory factor of Clp in L. enzymogenes. The key factor was important for the production of HSAF. The strains with high HSAF yield can presumably be constructed by deletion of the negative regulators or overexpression of the positive regulators by genetic engineering.
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Affiliation(s)
- Huiyong Xu
- Institute of Plant Protection, Jiangsu Academy of Agricultural Sciences, Nanjing, 210014, People's Republic of China
| | - Ruping Wang
- College of Plant Protection, Nanjing Agricultural University, China/Key Laboratory of Integrated Management of Crop Diseases and Pests (Nanjing Agricultural University, Ministry of Education), Nanjing, 210095, People's Republic of China
| | - Yangyang Zhao
- Institute of Plant Protection, Jiangsu Academy of Agricultural Sciences, Nanjing, 210014, People's Republic of China
| | - Zheng Qing Fu
- Department of Biological Sciences, University of South Carolina, Columbia, SC, 29208, USA
| | - Guoliang Qian
- College of Plant Protection, Nanjing Agricultural University, China/Key Laboratory of Integrated Management of Crop Diseases and Pests (Nanjing Agricultural University, Ministry of Education), Nanjing, 210095, People's Republic of China
| | - Fengquan Liu
- Institute of Plant Protection, Jiangsu Academy of Agricultural Sciences, Nanjing, 210014, People's Republic of China.
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31
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XCC2366, A Gene Encoding A Putative TetR Family Transcriptional Regulator, is Required for Acriflavin Resistance and Virulence of Xanthomonas campestris pv. campestris. Curr Microbiol 2017; 74:1373-1381. [DOI: 10.1007/s00284-017-1328-5] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2017] [Accepted: 08/04/2017] [Indexed: 10/19/2022]
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32
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Zhao X, Liu X, Xu X, Fu YV. Microbe social skill: the cell-to-cell communication between microorganisms. Sci Bull (Beijing) 2017; 62:516-524. [PMID: 36659262 DOI: 10.1016/j.scib.2017.02.010] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2017] [Revised: 02/05/2017] [Accepted: 02/06/2017] [Indexed: 01/21/2023]
Abstract
Although microbes primarily are single-cell organisms, they are not isolated individuals. Microbes use various means to communicate with one another. Based on the communication, microbes establish a social interaction with their neighbors in a specific ecological niche, and cooperative behaviors are normally performed to provide benefits on the population and species levels. In the microbiome era, in order to better understand the behaviors of microbes, deep understanding of the social communication between microbes hence becomes a key to interpret microbe behaviors. Here we summarize the molecular mechanisms that underlie the cell-to-cell communication in prokaryotic and eukaryotic microorganisms, the recent discoveries and novel technologies in understanding the interspecies and interkingdom communication, and discuss new concepts of the sociomicrobiology.
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Affiliation(s)
- Xi Zhao
- State Key Laboratory of Microbial Resources, Institute of Microbiology, Chinese Academy of Sciences, Beijing 100101, China; Savaid Medical School, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Xiong Liu
- State Key Laboratory of Microbial Resources, Institute of Microbiology, Chinese Academy of Sciences, Beijing 100101, China
| | - Xin Xu
- State Key Laboratory of Microbial Resources, Institute of Microbiology, Chinese Academy of Sciences, Beijing 100101, China
| | - Yu V Fu
- State Key Laboratory of Microbial Resources, Institute of Microbiology, Chinese Academy of Sciences, Beijing 100101, China; Savaid Medical School, University of Chinese Academy of Sciences, Beijing 100049, China.
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33
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Zhou L, Zhang LH, Cámara M, He YW. The DSF Family of Quorum Sensing Signals: Diversity, Biosynthesis, and Turnover. Trends Microbiol 2017; 25:293-303. [DOI: 10.1016/j.tim.2016.11.013] [Citation(s) in RCA: 105] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2016] [Revised: 11/09/2016] [Accepted: 11/22/2016] [Indexed: 01/18/2023]
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34
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Bhagirath AY, Pydi SP, Li Y, Lin C, Kong W, Chelikani P, Duan K. Characterization of the Direct Interaction between Hybrid Sensor Kinases PA1611 and RetS That Controls Biofilm Formation and the Type III Secretion System in Pseudomonas aeruginosa. ACS Infect Dis 2017; 3:162-175. [PMID: 27957853 DOI: 10.1021/acsinfecdis.6b00153] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
One of the leading causes of morbidity and mortality in cystic fibrosis (CF) patients is pulmonary infection with Pseudomonas aeruginosa, and the pathophysiology of pulmonary infection in CF is affected by the lifestyle of this micro-organism. RetS-GacS/A-RsmA is a key regulatory pathway in P. aeruginosa that determines the bacterium's lifestyle choice. Previously, we identified PA1611, a hybrid sensor kinase, as a new player in this pathway that interacts with RetS and influences biofilm formation and type III secretion system. In this study, we explored the structural and mechanistic basis of the interaction between PA1611 and RetS. We identified the amino acid residues critical for PA1611-RetS interactions by molecular modeling. These residues were then targeted for site-directed mutagenesis. Amino acid substitutions were carried out at seven key positions in PA1611 and at six corresponding key positions in RetS. The influence of such substitutions in PA1611 on the interaction was analyzed by bacterial two-hybrid assays. We carried out functional analysis of these mutants in P. aeruginosa for their effect on specific phenotypes. Two residues, F269 and E276, located within the histidine kinase A and histidine kinase-like ATPase domains of PA1611 were found to play crucial roles in the PA1611-RetS interaction and had profound effects on phenotypes. Corresponding mutations in RetS demonstrated similar results. We further confirmed that these mutations in PA1611 function through the GacS/GacA-RsmY/Z signaling pathway. Collectively, our findings provide a noncognate sensor kinase direct interaction model for a signaling pathway, key for lifestyle selection in P. aeruginosa, and targeting such interaction may serve as a novel way of controlling infections with P. aeruginosa.
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Affiliation(s)
- Anjali Y. Bhagirath
- Department of Oral
Biology and Manitoba Chemosensory Biology Research Group, College
of Dentistry, Rady Faculty of Health Sciences, 780 Bannatyne Avenue, Winnipeg, Manitoba, R3E 0W2, Canada
- Biology of Breathing
Group, Children’s Hospital Research Institute of Manitoba, 715 McDermot Avenue, Winnipeg, Manitoba R3E 3P4, Canada
| | - Sai P. Pydi
- Department of Oral
Biology and Manitoba Chemosensory Biology Research Group, College
of Dentistry, Rady Faculty of Health Sciences, 780 Bannatyne Avenue, Winnipeg, Manitoba, R3E 0W2, Canada
| | - Yanqi Li
- Department of Oral
Biology and Manitoba Chemosensory Biology Research Group, College
of Dentistry, Rady Faculty of Health Sciences, 780 Bannatyne Avenue, Winnipeg, Manitoba, R3E 0W2, Canada
- Biology of Breathing
Group, Children’s Hospital Research Institute of Manitoba, 715 McDermot Avenue, Winnipeg, Manitoba R3E 3P4, Canada
| | - Chen Lin
- Department of Oral
Biology and Manitoba Chemosensory Biology Research Group, College
of Dentistry, Rady Faculty of Health Sciences, 780 Bannatyne Avenue, Winnipeg, Manitoba, R3E 0W2, Canada
| | - Weina Kong
- Department of Oral
Biology and Manitoba Chemosensory Biology Research Group, College
of Dentistry, Rady Faculty of Health Sciences, 780 Bannatyne Avenue, Winnipeg, Manitoba, R3E 0W2, Canada
| | - Prashen Chelikani
- Department of Oral
Biology and Manitoba Chemosensory Biology Research Group, College
of Dentistry, Rady Faculty of Health Sciences, 780 Bannatyne Avenue, Winnipeg, Manitoba, R3E 0W2, Canada
- Biology of Breathing
Group, Children’s Hospital Research Institute of Manitoba, 715 McDermot Avenue, Winnipeg, Manitoba R3E 3P4, Canada
| | - Kangmin Duan
- Department of Oral
Biology and Manitoba Chemosensory Biology Research Group, College
of Dentistry, Rady Faculty of Health Sciences, 780 Bannatyne Avenue, Winnipeg, Manitoba, R3E 0W2, Canada
- Department of Medical
Microbiology and Infectious Diseases, Max Rady College of Medicine, Rady Faculty of Health Sciences, 745 Bannatyne Avenue, Winnipeg, Manitoba, R3E 0J9, Canada
- Biology of Breathing
Group, Children’s Hospital Research Institute of Manitoba, 715 McDermot Avenue, Winnipeg, Manitoba R3E 3P4, Canada
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35
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Dow J. Diffusible signal factor-dependent quorum sensing in pathogenic bacteria and its exploitation for disease control. J Appl Microbiol 2016; 122:2-11. [DOI: 10.1111/jam.13307] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2016] [Revised: 09/16/2016] [Accepted: 09/23/2016] [Indexed: 12/25/2022]
Affiliation(s)
- J.M. Dow
- School of Microbiology; University College Cork; Cork Ireland
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36
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Song Z, Zhao Y, Qian G, Odhiambo BO, Liu F. Novel insights into the regulatory roles of gene hshB in Xanthomonas oryzae pv. oryzicola. Res Microbiol 2016; 168:165-173. [PMID: 27810475 DOI: 10.1016/j.resmic.2016.10.007] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2016] [Revised: 10/15/2016] [Accepted: 10/24/2016] [Indexed: 12/16/2022]
Abstract
Xanthomonas oryzae pv. oryzicola causes leaf streak disease of rice. The gene hshB is a newly identified virulence-associated gene that is co-regulated by diffusible signal factor signaling and global regulator Clp in X. oryzae pv. oryzicola. Our previous study showed that mutation of hshB remarkably impaired the virulence, extracellular protease activity, extracellular polysaccharide production and resistance to oxidative stress of X. oryzae pv. oryzicola. In this study, the regulatory role of hshB in X. oryzae pv .oryzicola was expanded. Results showed that hshB was also required for cell swimming motility. Transcriptome analysis showed that 305 genes were significantly differentially expressed after deletion of hshB in X. oryzae pv. oryzicola. Further analysis of transcriptome data indicated that the differentially expressed genes focused on two aspects: namely, cell motility and cell signal transduction. This finding strongly identified the closely related function of hshB to cell motility and signal transduction. In addition, the mutation of hshB of X. oryzae pv. oryzicola enhanced biofilm formation. Collectively, the study showed novel functions of gene hshB in cell motility and biofilm formation by transcriptome analysis, thus expanding our understanding of the roles of gene hshB in the pathogenic X. oryzae pv. oryzicola.
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Affiliation(s)
- Zhiwei Song
- Institute of Plant Protection, Jiangsu Academy of Agricultural Science, Nanjing 210014, China
| | - Yancun Zhao
- Institute of Plant Protection, Jiangsu Academy of Agricultural Science, Nanjing 210014, China
| | - Guoliang Qian
- College of Plant Protection, Nanjing Agricultural University, Nanjing 210095, China; Key Laboratory of Integrated Management of Crop Diseases and Pests (Nanjing Agricultural University), Ministry of Education, China
| | - Benard Omondi Odhiambo
- College of Plant Protection, Nanjing Agricultural University, Nanjing 210095, China; Key Laboratory of Integrated Management of Crop Diseases and Pests (Nanjing Agricultural University), Ministry of Education, China
| | - Fengquan Liu
- Institute of Plant Protection, Jiangsu Academy of Agricultural Science, Nanjing 210014, China.
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Borland S, Prigent-Combaret C, Wisniewski-Dyé F. Bacterial hybrid histidine kinases in plant-bacteria interactions. MICROBIOLOGY-SGM 2016; 162:1715-1734. [PMID: 27609064 DOI: 10.1099/mic.0.000370] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Two-component signal transduction systems are essential for many bacteria to maintain homeostasis and adapt to environmental changes. Two-component signal transduction systems typically involve a membrane-bound histidine kinase that senses stimuli, autophosphorylates in the transmitter region and then transfers the phosphoryl group to the receiver domain of a cytoplasmic response regulator that mediates appropriate changes in bacterial physiology. Although usually found on distinct proteins, the transmitter and receiver modules are sometimes fused into a so-called hybrid histidine kinase (HyHK). Such structure results in multiple phosphate transfers that are believed to provide extra-fine-tuning mechanisms and more regulatory checkpoints than classical phosphotransfers. HyHK-based regulation may be crucial for finely tuning gene expression in a heterogeneous environment such as the rhizosphere, where intricate plant-bacteria interactions occur. In this review, we focus on roles fulfilled by bacterial HyHKs in plant-associated bacteria, providing recent findings on the mechanistic of their signalling properties. Recent insights into understanding additive regulatory properties fulfilled by the tethered receiver domain of HyHKs are also addressed.
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Affiliation(s)
- Stéphanie Borland
- Université de Lyon, Université Lyon 1, Ecologie Microbienne, CNRS UMR5557, INRA UMR1418, Villeurbanne, France
| | - Claire Prigent-Combaret
- Université de Lyon, Université Lyon 1, Ecologie Microbienne, CNRS UMR5557, INRA UMR1418, Villeurbanne, France
| | - Florence Wisniewski-Dyé
- Université de Lyon, Université Lyon 1, Ecologie Microbienne, CNRS UMR5557, INRA UMR1418, Villeurbanne, France
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38
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Dow JM, Naughton LM, Hollmann B, An SQ, Ryan RP. The Diffusible Signal Factor Family of Bacterial CellCell Signals. Isr J Chem 2016. [DOI: 10.1002/ijch.201500075] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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39
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Wang XY, Zhou L, Yang J, Ji GH, He YW. The RpfB-Dependent Quorum Sensing Signal Turnover System Is Required for Adaptation and Virulence in Rice Bacterial Blight Pathogen Xanthomonas oryzae pv. oryzae. MOLECULAR PLANT-MICROBE INTERACTIONS : MPMI 2016; 29:220-30. [PMID: 26667598 DOI: 10.1094/mpmi-09-15-0206-r] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/21/2023]
Abstract
Xanthomonas oryzae pv. oryzae, the bacterial blight pathogen of rice, produces diffusible signal factor (DSF) family quorum sensing signals to regulate virulence. The biosynthesis and perception of DSF family signals require components of the rpf (regulation of pathogenicity factors) cluster. In this study, we report that RpfB plays an essential role in DSF family signal turnover in X. oryzae pv. oryzae PXO99A. The production of DSF family signals was boosted by deletion of the rpfB gene and was abolished by its overexpression. The RpfC/RpfG-mediated DSF signaling system negatively regulates rpfB expression via the global transcription regulator Clp, whose activity is reversible in the presence of cyclic diguanylate monophosphate. These findings indicate that the DSF family signal turnover system in PXO99A is generally consistent with that in Xanthomonas campestris pv. campestris. Moreover, this study has revealed several specific roles of RpfB in PXO99A. First, the rpfB deletion mutant produced high levels of DSF family signals but reduced extracellular polysaccharide production, extracellular amylase activity, and attenuated pathogenicity. Second, the rpfB/rpfC double-deletion mutant was partially deficient in xanthomonadin production. Taken together, the RpfB-dependent DSF family signal turnover system is a conserved and naturally presenting signal turnover system in Xanthomonas spp., which plays unique roles in X. oryzae pv. oryzae adaptation and pathogenesis.
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Affiliation(s)
- Xing-Yu Wang
- 1 State Key Laboratory of Microbial Metabolism, School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai, 200240, China
| | - Lian Zhou
- 1 State Key Laboratory of Microbial Metabolism, School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai, 200240, China
| | - Jun Yang
- 2 College of Plant Protection, Yunnan Agricultural University, Kunming 650201, China
| | - Guang-Hai Ji
- 2 College of Plant Protection, Yunnan Agricultural University, Kunming 650201, China
| | - Ya-Wen He
- 1 State Key Laboratory of Microbial Metabolism, School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai, 200240, China
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40
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Lee HM, Liao CT, Chiang YC, Chang YY, Yeh YT, Du SC, Hsiao YM. Characterization of genes encoding proteins containing HD-related output domain in Xanthomonas campestris pv. campestris. Antonie van Leeuwenhoek 2016; 109:509-22. [PMID: 26821378 DOI: 10.1007/s10482-016-0656-y] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/14/2015] [Accepted: 01/19/2016] [Indexed: 11/30/2022]
Abstract
The Gram-negative plant pathogen Xanthomonas campestris pv. campestris (Xcc) is the causative agent of black rot in crucifers. The production of Xcc virulence factors is regulated by Clp and RpfF. HD-related output domain (HDOD) is a protein domain of unknown biochemical function. The genome of Xcc encodes three proteins (GsmR, HdpA, and HdpB) with an HDOD. The GsmR has been reported to play a role in the general stress response and cell motility and its expression is positively regulated by Clp. Here, the function and transcription of hdpA and hdpB were characterized. Mutation of hdpA resulted in enhanced bacterial attachment. In addition, the expression of hdpA was positively regulated by RpfF but not by Clp, subject to catabolite repression and affected by several stress conditions. However, mutational analysis and reporter assay showed that hdpB had no effect on the production of a range of virulence factors and its expression was independent of Clp and RpfF. The results shown here not only extend the previous work on RpfF regulation to show that it influences the expression of hdpA in Xcc, but also expand knowledge of the function of the HDOD containing proteins in bacteria.
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Affiliation(s)
- Hsien-Ming Lee
- Institute of Biotechnology, Central Taiwan University of Science and Technology, Taichung, 40601, Taiwan
| | - Chao-Tsai Liao
- Department of Medical Laboratory Science and Biotechnology, Central Taiwan University of Science and Technology, Taichung, 40601, Taiwan
| | - Ying-Chuan Chiang
- Department of Medical Laboratory Science and Biotechnology, Central Taiwan University of Science and Technology, Taichung, 40601, Taiwan
| | - Yu-Yin Chang
- Institute of Biotechnology, Central Taiwan University of Science and Technology, Taichung, 40601, Taiwan
| | - Yu-Tzu Yeh
- Department of Medical Laboratory Science and Biotechnology, Central Taiwan University of Science and Technology, Taichung, 40601, Taiwan
| | - Shin-Chiao Du
- Department of Medical Laboratory Science and Biotechnology, Central Taiwan University of Science and Technology, Taichung, 40601, Taiwan
| | - Yi-Min Hsiao
- Department of Medical Laboratory Science and Biotechnology, Central Taiwan University of Science and Technology, Taichung, 40601, Taiwan.
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41
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Liao CT, Liu YF, Chiang YC, Lo HH, Du SC, Hsu PC, Hsiao YM. Functional characterization and transcriptome analysis reveal multiple roles for prc in the pathogenicity of the black rot pathogen Xanthomonas campestris pv. campestris. Res Microbiol 2016; 167:299-312. [PMID: 26804425 DOI: 10.1016/j.resmic.2016.01.002] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2015] [Revised: 12/29/2015] [Accepted: 01/06/2016] [Indexed: 10/22/2022]
Abstract
Gram-negative phytopathogenic Xanthomonas campestris pv. campestris (Xcc) is the causal agent of black rot in crucifers. The ability of Xcc to incite this disease in plants depends on a number of factors, including exopolysaccharides, extracellular enzymes and biofilm production. In this study, transposon mutagenesis led to identification of the prc gene, encoding a tail-specific protease, which plays a role in Xcc pathogenesis. Mutation of prc resulted in decreased virulence, extracellular protease production and bacterial attachment, with restoration to the levels of wild type by the intact prc gene. From subsequent quantitative RT-PCR analysis and reporter assay, the major extracellular protease gene prt1, biofilm-related gene galE encoding a UDP-galactose 4-epimerase and two putative adhesin genes (yapH and XC_4290 encoding autotransporter-like protein H and hemagglutinin, respectively) were found to be reduced in the prc mutant. Results of transcriptome profiling of Xcc wild type and prc mutant by RNA sequencing (RNA-Seq) showed that mutation of prc in Xcc leads to alteration in the transcriptional levels (more than twofold) of 91 genes. These differentially expressed genes were associated with a wide range of biological functions such as carbohydrate transport and metabolism, cell wall/membrane biogenesis, posttranslational modification, protein turnover and chaperones, inorganic ion transport and metabolism and signal transduction mechanisms. The results of this study facilitate the functional understanding of and provide new information about the regulatory role of prc.
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Affiliation(s)
- Chao-Tsai Liao
- Department of Medical Laboratory Science and Biotechnology, Central Taiwan University of Science and Technology, Taichung 406, Taiwan.
| | - Yu-Fan Liu
- Department of Biomedical Sciences, Chung Shan Medical University, Taichung 402, Taiwan.
| | - Ying-Chuan Chiang
- Department of Medical Laboratory Science and Biotechnology, Central Taiwan University of Science and Technology, Taichung 406, Taiwan.
| | - Hsueh-Hsia Lo
- Department of Medical Laboratory Science and Biotechnology, Central Taiwan University of Science and Technology, Taichung 406, Taiwan.
| | - Shin-Chiao Du
- Department of Medical Laboratory Science and Biotechnology, Central Taiwan University of Science and Technology, Taichung 406, Taiwan.
| | - Pei-Chi Hsu
- Department of Medical Laboratory Science and Biotechnology, Central Taiwan University of Science and Technology, Taichung 406, Taiwan.
| | - Yi-Min Hsiao
- Department of Medical Laboratory Science and Biotechnology, Central Taiwan University of Science and Technology, Taichung 406, Taiwan.
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42
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The DSF type quorum sensing signalling system RpfF/R regulates diverse phenotypes in the opportunistic pathogen Cronobacter. Sci Rep 2016; 6:18753. [PMID: 26725701 PMCID: PMC4698668 DOI: 10.1038/srep18753] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2015] [Accepted: 11/25/2015] [Indexed: 12/11/2022] Open
Abstract
Several bacterial pathogens produce diffusible signal factor (DSF)-type quorum sensing (QS) signals to control biofilm formation and virulence. Previous work showed that in Burkholderia cenocepacia the RpfFBc/RpfR system is involved in sensing and responding to DSF signals and that this signal/sensor gene pair is highly conserved in several bacterial species including Cronobacter spp. Here we show that C. turicensis LMG 23827T possesses a functional RpfF/R system that is involved in the regulation of various phenotypes, including colony morphology, biofilm formation and swarming motility. In vivo experiments using the zebrafish embryo model revealed a role of this regulatory system in virulence of this opportunistic pathogen. We provide evidence that the RpfF/R system modulates the intracellular c-di-GMP level of the organism, an effect that may underpin the alteration in phenotype and thus the regulated phenotypes may be a consequence thereof. This first report on an RpfF/R-type QS system of an organism outside the genus Burkholderia revealed that both the underlying molecular mechanisms as well as the regulated functions show a high degree of conservation.
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43
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Yajima A. Recent Advances in the Chemistry and Chemical Biology of Quorum-Sensing Pheromones and Microbial Hormones. STUDIES IN NATURAL PRODUCTS CHEMISTRY 2016. [DOI: 10.1016/b978-0-444-63603-4.00010-3] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
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44
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Barel V, Chalupowicz L, Barash I, Sharabani G, Reuven M, Dror O, Burdman S, Manulis-Sasson S. Virulence and in planta movement of Xanthomonas hortorum pv. pelargonii are affected by the diffusible signal factor (DSF)-dependent quorum sensing system. MOLECULAR PLANT PATHOLOGY 2015; 16:710-23. [PMID: 25530086 PMCID: PMC6638389 DOI: 10.1111/mpp.12230] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/18/2023]
Abstract
Xanthomonas hortorum pv. pelargonii (Xhp), the causal agent of bacterial blight in pelargonium, is the most threatening bacterial disease of this ornamental worldwide. To gain an insight into the regulation of virulence in Xhp, we have disrupted the quorum sensing (QS) genes, which mediate the biosynthesis and sensing of the diffusible signal factor (DSF). Mutations in rpfF (encoding the DSF synthase) and rpfC (encoding the histidine sensor kinase of the two-component system RfpC/RpfG) and overexpression of rpfF showed a significant reduction in incidence and severity of the disease on pelargonium. Confocal laser scanning microscopy images of inoculated plants with a green fluorescent protein (GFP)-labelled wild-type strain showed that the pathogen is homogeneously dispersed in the lumen of xylem vessels, reaching the apex and invading the intercellular spaces of the leaf mesophyll tissue within 21 days. In contrast, the rpfF and rpfC knockout mutants, as well as the rpfF-overexpressing strain, remained confined to the vicinity of the inoculation site. The rpfF and rpfC mutants formed large incoherent aggregates in the xylem vessels that might interfere with upward movement of the bacterium within the plant. Both mutants also formed extended aggregates under in vitro conditions, whereas the wild-type strain formed microcolonies. Expression levels of putative virulence genes in planta were substantially reduced within 48 h after inoculation with the QS mutants when compared with the wild-type. The results presented indicate that an optimal DSF concentration is crucial for successful colonization and virulence of Xhp in pelargonium.
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Affiliation(s)
- Victoria Barel
- Department of Plant Pathology and Weed Research, Agricultural Research Organization, The Volcani Center, Bet Dagan, 50250, Israel
- Department of Plant Pathology and Microbiology, The Robert H. Smith Faculty of Agriculture, Food and Environment, The Hebrew University of Jerusalem, Rehovot, 76100, Israel
| | - Laura Chalupowicz
- Department of Plant Pathology and Weed Research, Agricultural Research Organization, The Volcani Center, Bet Dagan, 50250, Israel
| | - Isaac Barash
- Department of Molecular Biology and Ecology of Plants, Faculty of Life Sciences, Tel Aviv University, Tel Aviv, 61390, Israel
| | - Galit Sharabani
- Department of Plant Pathology and Weed Research, Agricultural Research Organization, The Volcani Center, Bet Dagan, 50250, Israel
| | - Michal Reuven
- Department of Plant Pathology and Weed Research, Agricultural Research Organization, The Volcani Center, Bet Dagan, 50250, Israel
| | - Orit Dror
- Department of Plant Pathology and Weed Research, Agricultural Research Organization, The Volcani Center, Bet Dagan, 50250, Israel
| | - Saul Burdman
- Department of Plant Pathology and Microbiology, The Robert H. Smith Faculty of Agriculture, Food and Environment, The Hebrew University of Jerusalem, Rehovot, 76100, Israel
| | - Shulamit Manulis-Sasson
- Department of Plant Pathology and Weed Research, Agricultural Research Organization, The Volcani Center, Bet Dagan, 50250, Israel
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45
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Zhou L, Wang XY, Sun S, Yang LC, Jiang BL, He YW. Identification and characterization of naturally occurring DSF-family quorum sensing signal turnover system in the phytopathogen Xanthomonas. Environ Microbiol 2015; 17:4646-58. [PMID: 26234930 DOI: 10.1111/1462-2920.12999] [Citation(s) in RCA: 41] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2015] [Revised: 07/14/2015] [Accepted: 07/21/2015] [Indexed: 11/30/2022]
Abstract
Molecules of the diffusible signal factor (DSF)-family are a class of quorum sensing (QS) signals used by the phytopathogens Xanthomonas. Studies during the last decade have outlined how Xanthomonas cells enter the QS phase. However, information on the mechanism underlying its exit from the QS phase is limited. RpfB has recently been reported as a fatty acyl-CoA ligase (FCL) that activates a wide range of fatty acids to their CoA esters in vitro. Here, we establish an improved quantification assay for DSF-family signals using liquid chromatography-mass spectrometry in X. campestris pv. campestris (Xcc). We first demonstrated that RpfB represents a naturally occurring DSF-family signal turnover system. RpfB effectively turns over DSF-family signals DSF and BDSF in vivo. RpfB FCL enzymatic activity is required for DSF and BDSF turnover. Deletion of rpfB slightly increased Xcc virulence in the Chinese radish and overexpression of rpfB significantly decreased virulence. We further showed that the expression of rpfB is growth phase-dependent, and its expression is significantly enhanced when Xcc cells enter the stationary phase. DSF regulates rpfB expression in a concentration-dependent manner. rpfB expression is also negatively regulated by the DSF signalling components RpfC, RpfG and Clp. The global transcription factor Clp directly binds to the AATGC-tgctgc-GCATC motif in the promoter region of rpfB to repress its expression. Finally, RpfB-dependent signal turnover system was detected in a wide range of bacterial species, suggesting that it is a conserved mechanism.
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Affiliation(s)
- Lian Zhou
- State Key Laboratory of Microbial Metabolism, Joint International Research Laboratory of Metabolic & Developmental Sciences, School of Life Sciences & Biotechnology, Shanghai Jiao Tong University, Shanghai, 200240, China
| | - Xing-Yu Wang
- State Key Laboratory of Microbial Metabolism, Joint International Research Laboratory of Metabolic & Developmental Sciences, School of Life Sciences & Biotechnology, Shanghai Jiao Tong University, Shanghai, 200240, China
| | - Shuang Sun
- State Key Laboratory of Microbial Metabolism, Joint International Research Laboratory of Metabolic & Developmental Sciences, School of Life Sciences & Biotechnology, Shanghai Jiao Tong University, Shanghai, 200240, China
| | - Li-Chao Yang
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-Bioresources, College of Life Science and Technology, Guangxi University, Nanning, 530004, China
| | - Bo-Le Jiang
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-Bioresources, College of Life Science and Technology, Guangxi University, Nanning, 530004, China
| | - Ya-Wen He
- State Key Laboratory of Microbial Metabolism, Joint International Research Laboratory of Metabolic & Developmental Sciences, School of Life Sciences & Biotechnology, Shanghai Jiao Tong University, Shanghai, 200240, China
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46
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Zhou L, Yu Y, Chen X, Diab AA, Ruan L, He J, Wang H, He YW. The Multiple DSF-family QS Signals are Synthesized from Carbohydrate and Branched-chain Amino Acids via the FAS Elongation Cycle. Sci Rep 2015; 5:13294. [PMID: 26289160 PMCID: PMC4542539 DOI: 10.1038/srep13294] [Citation(s) in RCA: 51] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2015] [Accepted: 07/21/2015] [Indexed: 12/29/2022] Open
Abstract
Members of the diffusible signal factor (DSF) family are a novel class of quorum sensing (QS) signals in diverse Gram-negative bacteria. Although previous studies have identified RpfF as a key enzyme for the biosynthesis of DSF family signals, many questions in their biosynthesis remain to be addressed. In this study with the phytopathogen Xanthomonas campestris pv. campestris (Xcc), we show that Xcc produces four DSF-family signals (DSF, BDSF, CDSF and IDSF) during cell culture, and that IDSF is a new functional signal characterized as cis-10-methyl-2-dodecenoic acid. Using a range of defined media, we further demonstrate that Xcc mainly produces BDSF in the presence of carbohydrates; leucine and valine are the primary precursor for DSF biosynthesis; isoleucine is the primary precursor for IDSF biosynthesis. Furthermore, our biochemical analyses show that the key DSF synthase RpfF has both thioesterase and dehydratase activities, and uses 3-hydroxydedecanoyl-ACP as a substrate to produce BDSF. Finally, our results show that the classic fatty acid synthesis elongation cycle is required for the biosynthesis of DSF-family signals. Taken all together, these findings establish a general biosynthetic pathway for the DSF-family quorum sensing signals.
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Affiliation(s)
- Lian Zhou
- State Key Laboratory of Microbial Metabolism, School of Life Sciences &Biotechnology, Shanghai Jiao Tong University, Shanghai 200240, China
| | - Yonghong Yu
- College of Life Sciences, South China Agricultural University, Guangzhou 510650, China
| | - Xiping Chen
- State Key Laboratory of Agricultural Microbiology, College of Life Science and Technology, Huazhong Agricultural University, Wuhan, 430070, China
| | - Abdelgader Abdeen Diab
- State Key Laboratory of Microbial Metabolism, School of Life Sciences &Biotechnology, Shanghai Jiao Tong University, Shanghai 200240, China
| | - Lifang Ruan
- State Key Laboratory of Agricultural Microbiology, College of Life Science and Technology, Huazhong Agricultural University, Wuhan, 430070, China
| | - Jin He
- State Key Laboratory of Agricultural Microbiology, College of Life Science and Technology, Huazhong Agricultural University, Wuhan, 430070, China
| | - Haihong Wang
- College of Life Sciences, South China Agricultural University, Guangzhou 510650, China
| | - Ya-Wen He
- State Key Laboratory of Microbial Metabolism, School of Life Sciences &Biotechnology, Shanghai Jiao Tong University, Shanghai 200240, China
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47
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Huedo P, Yero D, Martinez-Servat S, Ruyra À, Roher N, Daura X, Gibert I. Decoding the genetic and functional diversity of the DSF quorum-sensing system in Stenotrophomonas maltophilia. Front Microbiol 2015; 6:761. [PMID: 26284046 PMCID: PMC4517397 DOI: 10.3389/fmicb.2015.00761] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2015] [Accepted: 07/13/2015] [Indexed: 11/13/2022] Open
Abstract
Stenotrophomonas maltophilia uses the Diffusible Signal Factor (DSF) quorum sensing (QS) system to mediate intra- and inter-specific signaling and regulate virulence-related processes. The components of this system are encoded by the rpf cluster, with genes rpfF and rpfC encoding for the DSF synthase RpfF and sensor RpfC, respectively. Recently, we have shown that there exist two variants of the rpf cluster (rpf-1 and rpf-2), distinguishing two groups of S. maltophilia strains. Surprisingly, only rpf-1 strains produce detectable DSF, correlating with their ability to control biofilm formation, swarming motility and virulence. The evolutive advantage of acquiring two different rpf clusters, the phylogenetic time point and mechanism of this acquisition and the conditions that activate DSF production in rpf-2 strains, are however not known. Examination of this cluster in various species suggests that its variability originated most probably by genetic exchange between rhizosphere bacteria. We propose that rpf-2 variant strains make use of a strategy recently termed as "social cheating." Analysis of cellular and extracellular fatty acids (FAs) of strains E77 (rpf-1) and M30 (rpf-2) suggests that their RpfFs have also a thioesterase activity that facilitates the release of unspecific FAs to the medium in addition to DSF. Production of DSF in rpf-1 strains appears in fact to be modulated by some of these extracellular FAs in addition to other factors such as temperature and nutrients, while in rpf-2 strains DSF biosynthesis is derepressed only upon detection of DSF itself, suggesting that they require cohabitation with DSF-producer bacteria to activate their DSF regulatory machinery. Finally, we show that the mixed rpf-1/rpf-2 population presents synergism in DSF production and virulence capacity in an in vivo infection model. Recovery and quantification of DSF from co-infected animals correlates with the observed mortality rate.
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Affiliation(s)
- Pol Huedo
- Institut de Biotecnologia i de Biomedicina (IBB), Universitat Autònoma de Barcelona (UAB) Barcelona, Spain ; Departament de Genètica i de Microbiologia, Universitat Autònoma de Barcelona Barcelona, Spain
| | - Daniel Yero
- Institut de Biotecnologia i de Biomedicina (IBB), Universitat Autònoma de Barcelona (UAB) Barcelona, Spain ; Departament de Genètica i de Microbiologia, Universitat Autònoma de Barcelona Barcelona, Spain
| | - Sònia Martinez-Servat
- Institut de Biotecnologia i de Biomedicina (IBB), Universitat Autònoma de Barcelona (UAB) Barcelona, Spain ; Departament de Genètica i de Microbiologia, Universitat Autònoma de Barcelona Barcelona, Spain
| | - Àngels Ruyra
- Institut de Biotecnologia i de Biomedicina (IBB), Universitat Autònoma de Barcelona (UAB) Barcelona, Spain
| | - Nerea Roher
- Institut de Biotecnologia i de Biomedicina (IBB), Universitat Autònoma de Barcelona (UAB) Barcelona, Spain
| | - Xavier Daura
- Institut de Biotecnologia i de Biomedicina (IBB), Universitat Autònoma de Barcelona (UAB) Barcelona, Spain ; Catalan Institution for Research and Advanced Studies Barcelona, Spain
| | - Isidre Gibert
- Institut de Biotecnologia i de Biomedicina (IBB), Universitat Autònoma de Barcelona (UAB) Barcelona, Spain ; Departament de Genètica i de Microbiologia, Universitat Autònoma de Barcelona Barcelona, Spain
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Ryan RP, An SQ, Allan JH, McCarthy Y, Dow JM. The DSF Family of Cell-Cell Signals: An Expanding Class of Bacterial Virulence Regulators. PLoS Pathog 2015; 11:e1004986. [PMID: 26181439 PMCID: PMC4504480 DOI: 10.1371/journal.ppat.1004986] [Citation(s) in RCA: 132] [Impact Index Per Article: 14.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Many pathogenic bacteria use cell–cell signaling systems involving the synthesis and perception of diffusible signal molecules to control virulence as a response to cell density or confinement to niches. Bacteria produce signals of diverse structural classes. Signal molecules of the diffusible signal factor (DSF) family are cis-2-unsaturated fatty acids. The paradigm is cis-11-methyl-2-dodecenoic acid from Xanthomonas campestris pv. campestris (Xcc), which controls virulence in this plant pathogen. Although DSF synthesis was thought to be restricted to the xanthomonads, it is now known that structurally related molecules are produced by the unrelated bacteria Burkholderia cenocepacia and Pseudomonas aeruginosa. Furthermore, signaling involving these DSF family members contributes to bacterial virulence, formation of biofilms and antibiotic tolerance in these important human pathogens. Here we review the recent advances in understanding DSF signaling and its regulatory role in different bacteria. These advances include the description of the pathway/mechanism of DSF biosynthesis, identification of novel DSF synthases and new members of the DSF family, the demonstration of a diversity of DSF sensors to include proteins with a Per-Arnt-Sim (PAS) domain and the description of some of the signal transduction mechanisms that impinge on virulence factor expression. In addition, we address the role of DSF family signals in interspecies signaling that modulates the behavior of other microorganisms. Finally, we consider a number of recently reported approaches for the control of bacterial virulence through the modulation of DSF signaling.
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Affiliation(s)
- Robert P. Ryan
- Division of Molecular Microbiology, College of Life Sciences, University of Dundee, Dundee, United Kingdom
- * E-mail: (RPR); (JMD)
| | - Shi-qi An
- Division of Molecular Microbiology, College of Life Sciences, University of Dundee, Dundee, United Kingdom
| | - John H. Allan
- Division of Molecular Microbiology, College of Life Sciences, University of Dundee, Dundee, United Kingdom
| | - Yvonne McCarthy
- School of Microbiology, Biosciences Institute, University College Cork, Cork, Ireland
| | - J. Maxwell Dow
- School of Microbiology, Biosciences Institute, University College Cork, Cork, Ireland
- * E-mail: (RPR); (JMD)
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Song Z, Zhao Y, Zhou X, Wu G, Zhang Y, Qian G, Liu F. Identification and Characterization of Two Novel DSF-Controlled Virulence-Associated Genes Within the nodB-rhgB Locus of Xanthomonas oryzae pv. oryzicola Rs105. PHYTOPATHOLOGY 2015; 105:588-596. [PMID: 26020828 DOI: 10.1094/phyto-07-14-0190-r] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
Xanthomonas oryzae pv. oryzicola and X. oryzae pv. oryzae are two pathovars of X. oryzae that cause leaf streak and blight in rice, respectively. These two bacterial pathogens cause different disease symptoms by utilizing different infection sites on rice. Compared with X. oryzae pv. oryzae, the molecular virulence mechanism of X. oryzae pv. oryzicola remains largely unknown. Previously, we identified a unique diffusible signal factor (DSF)-controlled virulence-related gene (hshB) in X. oryzae pv. oryzicola Rs105 located in the nodB-rghB locus, which is absent in X. oryzae pv. oryzae PXO99(A). In the present study, we identified two additional genes within this locus (hshA and hshC) that were unique to X. oryzae pv. oryzicola Rs105 compared with X. oryzae pv. oryzae PXO99(A), and we found that the transcription of these genes was regulated by DSF signaling in X. oryzae pv. oryzicola. The mutation of these genes impaired the virulence of the wild-type Rs105 when using a low inoculation density of X. oryzae pv. oryzicola. In contrast to hshB, the mutation of these genes did not have any visible effect on characterized virulence-related functions, including in vitro growth, extracellular polysaccharide production, extracellular protease activity, and antioxidative ability. However, we found that mutation of hshA or hshC significantly reduced the in planta growth ability and epiphytic survival level of X. oryzae pv. oryzicola cells, which was the probable mechanisms of involvement of these two genes in virulence. Collectively, our studies of X. oryzae pv. oryzicola have identified two novel DSF-controlled virulence-associated genes (hshA and hshC), which will add to our understanding of the regulatory mechanisms of conserved DSF virulence signaling in Xanthomonas species.
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Affiliation(s)
- Zhiwei Song
- First, third, fourth, fifth, sixth, and seventh authors: College of Plant Protection, Nanjing Agricultural University, Nanjing 210095, China/Key Laboratory of Integrated Management of Crop Diseases and Pests (Nanjing Agricultural University), Ministry of Education, China; and second and seventh authors: Institute of Plant Protection, Jiangsu Academy of Agricultural Science, Nanjing 210014, P.R. China
| | - Yancun Zhao
- First, third, fourth, fifth, sixth, and seventh authors: College of Plant Protection, Nanjing Agricultural University, Nanjing 210095, China/Key Laboratory of Integrated Management of Crop Diseases and Pests (Nanjing Agricultural University), Ministry of Education, China; and second and seventh authors: Institute of Plant Protection, Jiangsu Academy of Agricultural Science, Nanjing 210014, P.R. China
| | - Xingyang Zhou
- First, third, fourth, fifth, sixth, and seventh authors: College of Plant Protection, Nanjing Agricultural University, Nanjing 210095, China/Key Laboratory of Integrated Management of Crop Diseases and Pests (Nanjing Agricultural University), Ministry of Education, China; and second and seventh authors: Institute of Plant Protection, Jiangsu Academy of Agricultural Science, Nanjing 210014, P.R. China
| | - Guichun Wu
- First, third, fourth, fifth, sixth, and seventh authors: College of Plant Protection, Nanjing Agricultural University, Nanjing 210095, China/Key Laboratory of Integrated Management of Crop Diseases and Pests (Nanjing Agricultural University), Ministry of Education, China; and second and seventh authors: Institute of Plant Protection, Jiangsu Academy of Agricultural Science, Nanjing 210014, P.R. China
| | - Yuqiang Zhang
- First, third, fourth, fifth, sixth, and seventh authors: College of Plant Protection, Nanjing Agricultural University, Nanjing 210095, China/Key Laboratory of Integrated Management of Crop Diseases and Pests (Nanjing Agricultural University), Ministry of Education, China; and second and seventh authors: Institute of Plant Protection, Jiangsu Academy of Agricultural Science, Nanjing 210014, P.R. China
| | - Guoliang Qian
- First, third, fourth, fifth, sixth, and seventh authors: College of Plant Protection, Nanjing Agricultural University, Nanjing 210095, China/Key Laboratory of Integrated Management of Crop Diseases and Pests (Nanjing Agricultural University), Ministry of Education, China; and second and seventh authors: Institute of Plant Protection, Jiangsu Academy of Agricultural Science, Nanjing 210014, P.R. China
| | - Fengquan Liu
- First, third, fourth, fifth, sixth, and seventh authors: College of Plant Protection, Nanjing Agricultural University, Nanjing 210095, China/Key Laboratory of Integrated Management of Crop Diseases and Pests (Nanjing Agricultural University), Ministry of Education, China; and second and seventh authors: Institute of Plant Protection, Jiangsu Academy of Agricultural Science, Nanjing 210014, P.R. China
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The host plant metabolite glucose is the precursor of diffusible signal factor (DSF) family signals in Xanthomonas campestris. Appl Environ Microbiol 2015; 81:2861-8. [PMID: 25681189 DOI: 10.1128/aem.03813-14] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023] Open
Abstract
Plant pathogen Xanthomonas campestris pv. campestris produces cis-11-methyl-2-dodecenoic acid (diffusible signal factor [DSF]) as a cell-cell communication signal to regulate biofilm dispersal and virulence factor production. Previous studies have demonstrated that DSF biosynthesis is dependent on the presence of RpfF, an enoyl-coenzyme A (CoA) hydratase, but the DSF synthetic mechanism and the influence of the host plant on DSF biosynthesis are still not clear. We show here that exogenous addition of host plant juice or ethanol extract to the growth medium of X. campestris pv. campestris could significantly boost DSF family signal production. It was subsequently revealed that X. campestris pv. campestris produces not only DSF but also BDSF (cis-2-dodecenoic acid) and another novel DSF family signal, which was designated DSF-II. BDSF was originally identified in Burkholderia cenocepacia to be involved in regulation of motility, biofilm formation, and virulence in B. cenocepacia. Functional analysis suggested that DSF-II plays a role equal to that of DSF in regulation of biofilm dispersion and virulence factor production in X. campestris pv. campestris. Furthermore, chromatographic separation led to identification of glucose as a specific molecule stimulating DSF family signal biosynthesis in X. campestris pv. campestris. (13)C-labeling experiments demonstrated that glucose acts as a substrate to provide a carbon element for DSF biosynthesis. The results of this study indicate that X. campestris pv. campestris could utilize a common metabolite of the host plant to enhance DSF family signal synthesis and therefore promote virulence.
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