1
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Saki N, Hadi H, Keikhaei B, Mirzaei A, Purrahman D. Gut microbiome composition and dysbiosis in immune thrombocytopenia: A review of literature. Blood Rev 2024; 67:101219. [PMID: 38862311 DOI: 10.1016/j.blre.2024.101219] [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: 02/16/2024] [Revised: 04/14/2024] [Accepted: 06/05/2024] [Indexed: 06/13/2024]
Abstract
Immune thrombocytopenia (ITP) is an autoimmune bleeding disorder characterized by excessive reticuloendothelial platelet destruction and inadequate compensatory platelet production. However, the pathogenesis of ITP is relatively complex, and its exact mechanisms and etiology have not been definitively established. The gut microbiome, namely a diverse community of symbiotic microorganisms residing in the gastrointestinal system, affects health through involvement in human metabolism, immune modulation, and maintaining physiological balance. Emerging evidence reveals that the gut microbiome composition differs in patients with ITP compared to healthy individuals, which is related with platelet count, disease duration, and response to treatment. These findings suggest that the microbiome and metabolome profiles of individuals could unveil a new pathway for aiding diagnosis, predicting prognosis, assessing treatment response, and formulating personalized therapeutic approaches for ITP. However, due to controversial reports, definitive conclusions cannot be drawn, and further investigations are needed.
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Affiliation(s)
- Najmaldin Saki
- Thalassemia & Hemoglobinopathy Research Center, Health Research Institute, Ahvaz Jundishapur University of Medical Sciences, Ahvaz, Iran
| | - Hakimeh Hadi
- Thalassemia & Hemoglobinopathy Research Center, Health Research Institute, Ahvaz Jundishapur University of Medical Sciences, Ahvaz, Iran
| | - Bijan Keikhaei
- Thalassemia & Hemoglobinopathy Research Center, Health Research Institute, Ahvaz Jundishapur University of Medical Sciences, Ahvaz, Iran
| | - Arezoo Mirzaei
- Department of Bacteriology and Virology, School of Medicine, Isfahan University of Medical Sciences, Isfahan, Iran
| | - Daryush Purrahman
- Thalassemia & Hemoglobinopathy Research Center, Health Research Institute, Ahvaz Jundishapur University of Medical Sciences, Ahvaz, Iran.
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2
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Irazoki O, Ter Beek J, Alvarez L, Mateus A, Colin R, Typas A, Savitski MM, Sourjik V, Berntsson RPA, Cava F. D-amino acids signal a stress-dependent run-away response in Vibrio cholerae. Nat Microbiol 2023; 8:1549-1560. [PMID: 37365341 PMCID: PMC10390336 DOI: 10.1038/s41564-023-01419-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2023] [Accepted: 05/31/2023] [Indexed: 06/28/2023]
Abstract
To explore favourable niches while avoiding threats, many bacteria use a chemotaxis navigation system. Despite decades of studies on chemotaxis, most signals and sensory proteins are still unknown. Many bacterial species release D-amino acids to the environment; however, their function remains largely unrecognized. Here we reveal that D-arginine and D-lysine are chemotactic repellent signals for the cholera pathogen Vibrio cholerae. These D-amino acids are sensed by a single chemoreceptor MCPDRK co-transcribed with the racemase enzyme that synthesizes them under the control of the stress-response sigma factor RpoS. Structural characterization of this chemoreceptor bound to either D-arginine or D-lysine allowed us to pinpoint the residues defining its specificity. Interestingly, the specificity for these D-amino acids appears to be restricted to those MCPDRK orthologues transcriptionally linked to the racemase. Our results suggest that D-amino acids can shape the biodiversity and structure of complex microbial communities under adverse conditions.
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Affiliation(s)
- Oihane Irazoki
- The Laboratory for Molecular Infection Medicine Sweden (MIMS), Umeå Center for Microbial Research (UCMR), Science for Life Laboratory (SciLifeLab), Department of Molecular Biology, Umeå University, Umeå, Sweden
| | - Josy Ter Beek
- Department of Medical Biochemistry and Biophysics, Umeå University, Umeå, Sweden
- Wallenberg Centre for Molecular Medicine, Umeå University, Umeå, Sweden
| | - Laura Alvarez
- The Laboratory for Molecular Infection Medicine Sweden (MIMS), Umeå Center for Microbial Research (UCMR), Science for Life Laboratory (SciLifeLab), Department of Molecular Biology, Umeå University, Umeå, Sweden
| | - André Mateus
- Genome Biology Unit, European Molecular Biology Laboratory, Heidelberg, Germany
| | - Remy Colin
- Max Planck Institute for Terrestrial Microbiology, and Center for Synthetic Microbiology (SYNMIKRO), Marburg, Germany
| | - Athanasios Typas
- Genome Biology Unit, European Molecular Biology Laboratory, Heidelberg, Germany
| | - Mikhail M Savitski
- Genome Biology Unit, European Molecular Biology Laboratory, Heidelberg, Germany
| | - Victor Sourjik
- Max Planck Institute for Terrestrial Microbiology, and Center for Synthetic Microbiology (SYNMIKRO), Marburg, Germany
| | - Ronnie P-A Berntsson
- Department of Medical Biochemistry and Biophysics, Umeå University, Umeå, Sweden
- Wallenberg Centre for Molecular Medicine, Umeå University, Umeå, Sweden
| | - Felipe Cava
- The Laboratory for Molecular Infection Medicine Sweden (MIMS), Umeå Center for Microbial Research (UCMR), Science for Life Laboratory (SciLifeLab), Department of Molecular Biology, Umeå University, Umeå, Sweden.
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3
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Gálvez-Roldán C, Cerna-Vargas JP, Rodríguez-Herva JJ, Krell T, Santamaría-Hernando S, López-Solanilla E. A Nitrate-Sensing Domain-Containing Chemoreceptor Is Required for Successful Entry and Virulence of Dickeya dadantii 3937 in Potato Plants. PHYTOPATHOLOGY 2023; 113:390-399. [PMID: 36399025 DOI: 10.1094/phyto-10-22-0367-r] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/16/2023]
Abstract
Nitrate metabolism plays an important role in bacterial physiology. During the interaction of plant-pathogenic bacteria with their hosts, bacteria face variable conditions with respect to nitrate availability. Perception mechanisms through the chemosensory pathway drive the entry and control the colonization of the plant host in phytopathogenic bacteria. In this work, the identification and characterization of the nitrate- and nitrite-sensing (NIT) domain-containing chemoreceptor of Dickeya dadantii 3937 (Dd3937) allowed us to unveil the key role of nitrate sensing not only for the entry into the plant apoplast through wounds but also for infection success. We determined the specificity of this chemoreceptor to bind nitrate and nitrite, with a slight ligand preference for nitrate. Gene expression analysis showed that nitrate perception controls not only the expression of nitrate reductase genes involved in respiratory and assimilatory metabolic processes but also the expression of gyrA, hrpN, and bgxA, three well-known virulence determinants in Dd3937.
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Affiliation(s)
- Clara Gálvez-Roldán
- Centro de Biotecnología y Genómica de Plantas CBGP, Universidad Politécnica de Madrid-Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria/CSIC, Parque Científico y Tecnológico de la UPM, Pozuelo de Alarcón, Madrid, Spain
| | - Jean Paul Cerna-Vargas
- Centro de Biotecnología y Genómica de Plantas CBGP, Universidad Politécnica de Madrid-Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria/CSIC, Parque Científico y Tecnológico de la UPM, Pozuelo de Alarcón, Madrid, Spain
- Departamento de Protección Ambiental, Estación Experimental del Zaidín, Consejo Superior de Investigaciones Científicas, Granada, Spain
| | - José Juan Rodríguez-Herva
- Centro de Biotecnología y Genómica de Plantas CBGP, Universidad Politécnica de Madrid-Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria/CSIC, Parque Científico y Tecnológico de la UPM, Pozuelo de Alarcón, Madrid, Spain
- Departamento de Biotecnología-Biología Vegetal, Escuela Técnica Superior de Ingeniería Agronómica, Alimentaria y de Biosistemas, Universidad Politécnica de Madrid, Madrid, Spain
| | - Tino Krell
- Departamento de Protección Ambiental, Estación Experimental del Zaidín, Consejo Superior de Investigaciones Científicas, Granada, Spain
| | - Saray Santamaría-Hernando
- Centro de Biotecnología y Genómica de Plantas CBGP, Universidad Politécnica de Madrid-Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria/CSIC, Parque Científico y Tecnológico de la UPM, Pozuelo de Alarcón, Madrid, Spain
| | - Emilia López-Solanilla
- Centro de Biotecnología y Genómica de Plantas CBGP, Universidad Politécnica de Madrid-Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria/CSIC, Parque Científico y Tecnológico de la UPM, Pozuelo de Alarcón, Madrid, Spain
- Departamento de Biotecnología-Biología Vegetal, Escuela Técnica Superior de Ingeniería Agronómica, Alimentaria y de Biosistemas, Universidad Politécnica de Madrid, Madrid, Spain
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4
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Santamaría‐Hernando S, López‐Maroto Á, Galvez‐Roldán C, Munar‐Palmer M, Monteagudo‐Cascales E, Rodríguez‐Herva J, Krell T, López‐Solanilla E. Pseudomonas syringae pv. tomato infection of tomato plants is mediated by GABA and l-Pro chemoperception. MOLECULAR PLANT PATHOLOGY 2022; 23:1433-1445. [PMID: 35689388 PMCID: PMC9452764 DOI: 10.1111/mpp.13238] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/22/2022] [Revised: 05/19/2022] [Accepted: 05/23/2022] [Indexed: 05/27/2023]
Abstract
Foliar bacterial pathogens have to penetrate the plant tissue and access the interior of the apoplast in order to initiate the pathogenic phase. The entry process is driven by chemotaxis towards plant-derived compounds in order to locate plant openings. However, information on plant signals recognized by bacterial chemoreceptors is scarce. Here, we show that the perception of GABA and l-Pro, two abundant components of the tomato apoplast, through the PsPto-PscC chemoreceptor drives the entry of Pseudomonas syringae pv. tomato into the tomato apoplast. The recognition of both compounds by PsPto-PscC caused chemoattraction to both amino acids and participated in the regulation of GABA catabolism. Mutation of the PsPto-PscC chemoreceptor caused a reduced chemotactic response towards these compounds which in turn impaired entry and reduced virulence in tomato plants. Interestingly, GABA and l-Pro levels significantly increase in tomato plants upon pathogen infection and are involved in the regulation of the plant defence response. This is an example illustrating how bacteria respond to plant signals produced during the interaction as cues to access the plant apoplast and to ensure efficient infection.
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Affiliation(s)
- Saray Santamaría‐Hernando
- Centro de Biotecnología y Genómica de Plantas CBGPUniversidad Politécnica de Madrid‐Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria/CSIC, Parque Científico y Tecnológico de la UPM Pozuelo de AlarcónMadridSpain
| | - Álvaro López‐Maroto
- Centro de Biotecnología y Genómica de Plantas CBGPUniversidad Politécnica de Madrid‐Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria/CSIC, Parque Científico y Tecnológico de la UPM Pozuelo de AlarcónMadridSpain
| | - Clara Galvez‐Roldán
- Centro de Biotecnología y Genómica de Plantas CBGPUniversidad Politécnica de Madrid‐Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria/CSIC, Parque Científico y Tecnológico de la UPM Pozuelo de AlarcónMadridSpain
| | - Martí Munar‐Palmer
- Centro de Biotecnología y Genómica de Plantas CBGPUniversidad Politécnica de Madrid‐Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria/CSIC, Parque Científico y Tecnológico de la UPM Pozuelo de AlarcónMadridSpain
| | - Elizabet Monteagudo‐Cascales
- Departamento de Protección AmbientalEstación Experimental del Zaidín, Consejo Superior de Investigaciones CientíficasGranadaSpain
| | - José‐Juan Rodríguez‐Herva
- Centro de Biotecnología y Genómica de Plantas CBGPUniversidad Politécnica de Madrid‐Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria/CSIC, Parque Científico y Tecnológico de la UPM Pozuelo de AlarcónMadridSpain
- Departamento de Biotecnología‐Biología VegetalEscuela Técnica Superior de Ingeniería Agronómica, Alimentaria y de Biosistemas, Universidad Politécnica de MadridMadridSpain
| | - Tino Krell
- Departamento de Protección AmbientalEstación Experimental del Zaidín, Consejo Superior de Investigaciones CientíficasGranadaSpain
| | - Emilia López‐Solanilla
- Centro de Biotecnología y Genómica de Plantas CBGPUniversidad Politécnica de Madrid‐Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria/CSIC, Parque Científico y Tecnológico de la UPM Pozuelo de AlarcónMadridSpain
- Departamento de Biotecnología‐Biología VegetalEscuela Técnica Superior de Ingeniería Agronómica, Alimentaria y de Biosistemas, Universidad Politécnica de MadridMadridSpain
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5
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Rico‐Jiménez M, Roca A, Krell T, Matilla MA. A bacterial chemoreceptor that mediates chemotaxis to two different plant hormones. Environ Microbiol 2022; 24:3580-3597. [PMID: 35088505 PMCID: PMC9543091 DOI: 10.1111/1462-2920.15920] [Citation(s) in RCA: 19] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2021] [Revised: 01/14/2022] [Accepted: 01/20/2022] [Indexed: 11/30/2022]
Abstract
Indole-3-acetic acid (IAA) is the main naturally occurring auxin and is produced by organisms of all kingdoms of life. In addition to the regulation of plant growth and development, IAA plays an important role in the interaction between plants and growth-promoting and phytopathogenic bacteria by regulating bacterial gene expression and physiology. We show here that an IAA metabolizing plant-associated Pseudomonas putida isolate exhibits chemotaxis to IAA that is independent of auxin metabolism. We found that IAA chemotaxis is based on the activity of the PcpI chemoreceptor and heterologous expression of pcpI conferred IAA taxis to different environmental and human pathogenic isolates of the Pseudomonas genus. Using ligand screening, microcalorimetry and quantitative chemotaxis assays, we found that PcpI failed to bind IAA directly, but recognized and mediated chemoattractions to various aromatic compounds, including the phytohormone salicylic acid. The expression of pcpI and its role in the interactions with plants was also investigated. PcpI extends the range of central signal molecules recognized by chemoreceptors. To our knowledge, this is the first report on a bacterial receptor that responds to two different phytohormones. Our study reinforces the multifunctional role of IAA and salicylic acid as intra- and inter-kingdom signal molecules.
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Affiliation(s)
- Miriam Rico‐Jiménez
- Department of Environmental Protection, Estación Experimental del Zaidín, Consejo Superior de Investigaciones CientíficasGranadaSpain
| | - Amalia Roca
- Department of Microbiology, Facultad de FarmaciaCampus Universitario de Cartuja, Universidad de GranadaGranada18071Spain
| | - Tino Krell
- Department of Environmental Protection, Estación Experimental del Zaidín, Consejo Superior de Investigaciones CientíficasGranadaSpain
| | - Miguel A. Matilla
- Department of Environmental Protection, Estación Experimental del Zaidín, Consejo Superior de Investigaciones CientíficasGranadaSpain
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6
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Wang P, Zhang G, Xu Z, Chen Z, Liu X, Wang C, Zheng C, Wang J, Zhang H, Yan A. Whole-cell FRET monitoring of transcription factor activities enables functional annotation of signal transduction systems in living bacteria. J Biol Chem 2022; 298:102258. [PMID: 35839853 PMCID: PMC9396075 DOI: 10.1016/j.jbc.2022.102258] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2022] [Revised: 06/29/2022] [Accepted: 07/01/2022] [Indexed: 11/24/2022] Open
Abstract
Bacteria adapt to their constantly changing environments largely by transcriptional regulation through the activities of various transcription factors (TFs). However, techniques that monitor TF–promoter interactions in situ in living bacteria are lacking. Herein, we developed a whole-cell TF–promoter binding assay based on the intermolecular FRET between an unnatural amino acid, l-(7-hydroxycoumarin-4-yl) ethylglycine, which labels TFs with bright fluorescence through genetic encoding (donor fluorophore) and the live cell nucleic acid stain SYTO 9 (acceptor fluorophore). We show that this new FRET pair monitors the intricate TF–promoter interactions elicited by various types of signal transduction systems, including one-component (CueR) and two-component systems (BasSR and PhoPQ), in bacteria with high specificity and sensitivity. We demonstrate that robust CouA incorporation and FRET occurrence is achieved in all these regulatory systems based on either the crystal structures of TFs or their simulated structures, if 3D structures of the TFs were unavailable. Furthermore, using CueR and PhoPQ systems as models, we demonstrate that the whole-cell FRET assay is applicable for the identification and validation of complex regulatory circuit and novel modulators of regulatory systems of interest. Finally, we show that the FRET system is applicable for single-cell analysis and monitoring TF activities in Escherichia coli colonizing a Caenorhabditis elegans host. In conclusion, we established a tractable and sensitive TF–promoter binding assay, which not only complements currently available approaches for DNA–protein interactions but also provides novel opportunities for functional annotation of bacterial signal transduction systems and studies of the bacteria–host interface.
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Affiliation(s)
- Pengchao Wang
- School of Biological Sciences, The University of Hong Kong, Pokfulam Road, Hong Kong SAR, China; Department of Biology, School of Life Sciences, Southern University of Science and Technology, Shenzhen 518055, Guangdong, China
| | - Guangming Zhang
- School of Biological Sciences, The University of Hong Kong, Pokfulam Road, Hong Kong SAR, China
| | - Zeling Xu
- School of Biological Sciences, The University of Hong Kong, Pokfulam Road, Hong Kong SAR, China
| | - Zhe Chen
- School of Biological Sciences, The University of Hong Kong, Pokfulam Road, Hong Kong SAR, China
| | - Xiaohong Liu
- Institute of Biophysics, Chinese Academy of Sciences, Beijing, 15 Datun Road, Chaoyang District, Beijing 100101, China
| | - Chenyin Wang
- School of Biological Sciences, The University of Hong Kong, Pokfulam Road, Hong Kong SAR, China
| | - Chaogu Zheng
- School of Biological Sciences, The University of Hong Kong, Pokfulam Road, Hong Kong SAR, China
| | - Jiangyun Wang
- Institute of Biophysics, Chinese Academy of Sciences, Beijing, 15 Datun Road, Chaoyang District, Beijing 100101, China.
| | - Hongmin Zhang
- Department of Biology, School of Life Sciences, Southern University of Science and Technology, Shenzhen 518055, Guangdong, China.
| | - Aixin Yan
- School of Biological Sciences, The University of Hong Kong, Pokfulam Road, Hong Kong SAR, China.
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7
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Monteagudo-Cascales E, Santero E, Canosa I. The Regulatory Hierarchy Following Signal Integration by the CbrAB Two-Component System: Diversity of Responses and Functions. Genes (Basel) 2022; 13:genes13020375. [PMID: 35205417 PMCID: PMC8871633 DOI: 10.3390/genes13020375] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2022] [Revised: 02/14/2022] [Accepted: 02/16/2022] [Indexed: 02/04/2023] Open
Abstract
CbrAB is a two-component system, unique to bacteria of the family Pseudomonaceae, capable of integrating signals and involved in a multitude of physiological processes that allow bacterial adaptation to a wide variety of varying environmental conditions. This regulatory system provides a great metabolic versatility that results in excellent adaptability and metabolic optimization. The two-component system (TCS) CbrA-CbrB is on top of a hierarchical regulatory cascade and interacts with other regulatory systems at different levels, resulting in a robust output. Among the regulatory systems found at the same or lower levels of CbrAB are the NtrBC nitrogen availability adaptation system, the Crc/Hfq carbon catabolite repression cascade in Pseudomonas, or interactions with the GacSA TCS or alternative sigma ECF factor, such as SigX. The interplay between regulatory mechanisms controls a number of physiological processes that intervene in important aspects of bacterial adaptation and survival. These include the hierarchy in the use of carbon sources, virulence or resistance to antibiotics, stress response or definition of the bacterial lifestyle. The multiple actions of the CbrAB TCS result in an important competitive advantage.
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Affiliation(s)
| | - Eduardo Santero
- Departamento de Biología Molecular e Ingeniería Bioquímica, Universidad Pablo de Olavide, Centro Andaluz de Biología del Desarrollo, CSIC, Junta de Andalucía, 41013 Seville, Spain;
| | - Inés Canosa
- Departamento de Biología Molecular e Ingeniería Bioquímica, Universidad Pablo de Olavide, Centro Andaluz de Biología del Desarrollo, CSIC, Junta de Andalucía, 41013 Seville, Spain;
- Correspondence: ; Tel.: +34-954349052
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8
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Matilla MA, Velando F, Martín-Mora D, Monteagudo-Cascales E, Krell T. A catalogue of signal molecules that interact with sensor kinases, chemoreceptors and transcriptional regulators. FEMS Microbiol Rev 2021; 46:6356564. [PMID: 34424339 DOI: 10.1093/femsre/fuab043] [Citation(s) in RCA: 57] [Impact Index Per Article: 19.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2021] [Accepted: 08/10/2021] [Indexed: 12/12/2022] Open
Abstract
Bacteria have evolved many different signal transduction systems that sense signals and generate a variety of responses. Generally, most abundant are transcriptional regulators, sensor histidine kinases and chemoreceptors. Typically, these systems recognize their signal molecules with dedicated ligand-binding domains (LBDs), which, in turn, generate a molecular stimulus that modulates the activity of the output module. There are an enormous number of different LBDs that recognize a similarly diverse set of signals. To give a global perspective of the signals that interact with transcriptional regulators, sensor kinases and chemoreceptors, we manually retrieved information on the protein-ligand interaction from about 1,200 publications and 3D structures. The resulting 811 proteins were classified according to the Pfam family into 127 groups. These data permit a delineation of the signal profiles of individual LBD families as well as distinguishing between families that recognize signals in a promiscuous manner and those that possess a well-defined ligand range. A major bottleneck in the field is the fact that the signal input of many signaling systems is unknown. The signal repertoire reported here will help the scientific community design experimental strategies to identify the signaling molecules for uncharacterised sensor proteins.
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Affiliation(s)
- Miguel A Matilla
- Department of Environmental Protection, Estación Experimental del Zaidín, Consejo Superior de Investigaciones Científicas, Prof. Albareda 1, 18008 Granada, Spain
| | - Félix Velando
- Department of Environmental Protection, Estación Experimental del Zaidín, Consejo Superior de Investigaciones Científicas, Prof. Albareda 1, 18008 Granada, Spain
| | - David Martín-Mora
- Department of Environmental Protection, Estación Experimental del Zaidín, Consejo Superior de Investigaciones Científicas, Prof. Albareda 1, 18008 Granada, Spain
| | - Elizabet Monteagudo-Cascales
- Department of Environmental Protection, Estación Experimental del Zaidín, Consejo Superior de Investigaciones Científicas, Prof. Albareda 1, 18008 Granada, Spain
| | - Tino Krell
- Department of Environmental Protection, Estación Experimental del Zaidín, Consejo Superior de Investigaciones Científicas, Prof. Albareda 1, 18008 Granada, Spain
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9
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Gushchin I, Aleksenko VA, Orekhov P, Goncharov IM, Nazarenko VV, Semenov O, Remeeva A, Gordeliy V. Nitrate- and Nitrite-Sensing Histidine Kinases: Function, Structure, and Natural Diversity. Int J Mol Sci 2021; 22:5933. [PMID: 34072989 PMCID: PMC8199190 DOI: 10.3390/ijms22115933] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2021] [Revised: 05/27/2021] [Accepted: 05/28/2021] [Indexed: 12/18/2022] Open
Abstract
Under anaerobic conditions, bacteria may utilize nitrates and nitrites as electron acceptors. Sensitivity to nitrous compounds is achieved via several mechanisms, some of which rely on sensor histidine kinases (HKs). The best studied nitrate- and nitrite-sensing HKs (NSHKs) are NarQ and NarX from Escherichia coli. Here, we review the function of NSHKs, analyze their natural diversity, and describe the available structural information. In particular, we show that around 6000 different NSHK sequences forming several distinct clusters may now be found in genomic databases, comprising mostly the genes from Beta- and Gammaproteobacteria as well as from Bacteroidetes and Chloroflexi, including those from anaerobic ammonia oxidation (annamox) communities. We show that the architecture of NSHKs is mostly conserved, although proteins from Bacteroidetes lack the HAMP and GAF-like domains yet sometimes have PAS. We reconcile the variation of NSHK sequences with atomistic models and pinpoint the structural elements important for signal transduction from the sensor domain to the catalytic module over the transmembrane and cytoplasmic regions spanning more than 200 Å.
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Affiliation(s)
- Ivan Gushchin
- Research Center for Molecular Mechanisms of Aging and Age-Related Diseases, Moscow Institute of Physics and Technology, 141700 Dolgoprudny, Russia; (V.A.A.); (P.O.); (I.M.G.); (V.V.N.); (O.S.); (A.R.)
| | - Vladimir A. Aleksenko
- Research Center for Molecular Mechanisms of Aging and Age-Related Diseases, Moscow Institute of Physics and Technology, 141700 Dolgoprudny, Russia; (V.A.A.); (P.O.); (I.M.G.); (V.V.N.); (O.S.); (A.R.)
| | - Philipp Orekhov
- Research Center for Molecular Mechanisms of Aging and Age-Related Diseases, Moscow Institute of Physics and Technology, 141700 Dolgoprudny, Russia; (V.A.A.); (P.O.); (I.M.G.); (V.V.N.); (O.S.); (A.R.)
- Faculty of Biology, M.V. Lomonosov Moscow State University, 119991 Moscow, Russia
| | - Ivan M. Goncharov
- Research Center for Molecular Mechanisms of Aging and Age-Related Diseases, Moscow Institute of Physics and Technology, 141700 Dolgoprudny, Russia; (V.A.A.); (P.O.); (I.M.G.); (V.V.N.); (O.S.); (A.R.)
| | - Vera V. Nazarenko
- Research Center for Molecular Mechanisms of Aging and Age-Related Diseases, Moscow Institute of Physics and Technology, 141700 Dolgoprudny, Russia; (V.A.A.); (P.O.); (I.M.G.); (V.V.N.); (O.S.); (A.R.)
| | - Oleg Semenov
- Research Center for Molecular Mechanisms of Aging and Age-Related Diseases, Moscow Institute of Physics and Technology, 141700 Dolgoprudny, Russia; (V.A.A.); (P.O.); (I.M.G.); (V.V.N.); (O.S.); (A.R.)
| | - Alina Remeeva
- Research Center for Molecular Mechanisms of Aging and Age-Related Diseases, Moscow Institute of Physics and Technology, 141700 Dolgoprudny, Russia; (V.A.A.); (P.O.); (I.M.G.); (V.V.N.); (O.S.); (A.R.)
| | - Valentin Gordeliy
- Research Center for Molecular Mechanisms of Aging and Age-Related Diseases, Moscow Institute of Physics and Technology, 141700 Dolgoprudny, Russia; (V.A.A.); (P.O.); (I.M.G.); (V.V.N.); (O.S.); (A.R.)
- Institut de Biologie Structurale J.-P. Ebel, Université Grenoble Alpes-CEA-CNRS, 38000 Grenoble, France
- Institute of Biological Information Processing (IBI-7: Structural Biochemistry), Forschungszentrum Jülich, 52428 Jülich, Germany
- JuStruct: Jülich Center for Structural Biology, Forschungszentrum Jülich, 52428 Jülich, Germany
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Matilla MA, Ortega Á, Krell T. The role of solute binding proteins in signal transduction. Comput Struct Biotechnol J 2021; 19:1786-1805. [PMID: 33897981 PMCID: PMC8050422 DOI: 10.1016/j.csbj.2021.03.029] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2021] [Revised: 03/22/2021] [Accepted: 03/22/2021] [Indexed: 12/13/2022] Open
Abstract
The solute binding proteins (SBPs) of prokaryotes are present in the extracytosolic space. Although their primary function is providing substrates to transporters, SBPs also stimulate different signaling proteins, including chemoreceptors, sensor kinases, diguanylate cyclases/phosphodiesterases and Ser/Thr kinases, thereby causing a wide range of responses. While relatively few such systems have been identified, several pieces of evidence suggest that SBP-mediated receptor activation is a widespread mechanism. (1) These systems have been identified in Gram-positive and Gram-negative bacteria and archaea. (2) There is a structural diversity in the receptor domains that bind SBPs. (3) SBPs belonging to thirteen different families interact with receptor ligand binding domains (LBDs). (4) For the two most abundant receptor LBD families, dCache and four-helix-bundle, there are different modes of interaction with SBPs. (5) SBP-stimulated receptors carry out many different functions. The advantage of SBP-mediated receptor stimulation is attributed to a strict control of SBP levels, which allows a precise adjustment of the systeḿs sensitivity. We have compiled information on the effect of ligands on the transcript/protein levels of their cognate SBPs. In 87 % of the cases analysed, ligands altered SBP expression levels. The nature of the regulatory effect depended on the ligand family. Whereas inorganic ligands typically downregulate SBP expression, an upregulation was observed in response to most sugars and organic acids. A major unknown is the role that SBPs play in signaling and in receptor stimulation. This review attempts to summarize what is known and to present new information to narrow this gap in knowledge.
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Affiliation(s)
- Miguel A Matilla
- Department of Environmental Protection, Estación Experimental del Zaidín, Consejo Superior de Investigaciones Científicas, Prof. Albareda 1, Granada 18008, Spain
| | - Álvaro Ortega
- Department of Biochemistry and Molecular Biology 'B' and Immunology, Faculty of Chemistry, University of Murcia, Regional Campus of International Excellence "Campus Mare Nostrum", Murcia, Spain
| | - Tino Krell
- Department of Environmental Protection, Estación Experimental del Zaidín, Consejo Superior de Investigaciones Científicas, Prof. Albareda 1, Granada 18008, Spain
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11
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Mohapatra B, Phale PS. Microbial Degradation of Naphthalene and Substituted Naphthalenes: Metabolic Diversity and Genomic Insight for Bioremediation. Front Bioeng Biotechnol 2021; 9:602445. [PMID: 33791281 PMCID: PMC8006333 DOI: 10.3389/fbioe.2021.602445] [Citation(s) in RCA: 40] [Impact Index Per Article: 13.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2020] [Accepted: 02/09/2021] [Indexed: 12/21/2022] Open
Abstract
Low molecular weight polycyclic aromatic hydrocarbons (PAHs) like naphthalene and substituted naphthalenes (methylnaphthalene, naphthoic acids, 1-naphthyl N-methylcarbamate, etc.) are used in various industries and exhibit genotoxic, mutagenic, and/or carcinogenic effects on living organisms. These synthetic organic compounds (SOCs) or xenobiotics are considered as priority pollutants that pose a critical environmental and public health concern worldwide. The extent of anthropogenic activities like emissions from coal gasification, petroleum refining, motor vehicle exhaust, and agricultural applications determine the concentration, fate, and transport of these ubiquitous and recalcitrant compounds. Besides physicochemical methods for cleanup/removal, a green and eco-friendly technology like bioremediation, using microbes with the ability to degrade SOCs completely or convert to non-toxic by-products, has been a safe, cost-effective, and promising alternative. Various bacterial species from soil flora belonging to Proteobacteria (Pseudomonas, Pseudoxanthomonas, Comamonas, Burkholderia, and Novosphingobium), Firmicutes (Bacillus and Paenibacillus), and Actinobacteria (Rhodococcus and Arthrobacter) displayed the ability to degrade various SOCs. Metabolic studies, genomic and metagenomics analyses have aided our understanding of the catabolic complexity and diversity present in these simple life forms which can be further applied for efficient biodegradation. The prolonged persistence of PAHs has led to the evolution of new degradative phenotypes through horizontal gene transfer using genetic elements like plasmids, transposons, phages, genomic islands, and integrative conjugative elements. Systems biology and genetic engineering of either specific isolates or mock community (consortia) might achieve complete, rapid, and efficient bioremediation of these PAHs through synergistic actions. In this review, we highlight various metabolic routes and diversity, genetic makeup and diversity, and cellular responses/adaptations by naphthalene and substituted naphthalene-degrading bacteria. This will provide insights into the ecological aspects of field application and strain optimization for efficient bioremediation.
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Affiliation(s)
- Balaram Mohapatra
- Department of Biosciences and Bioengineering, Indian Institute of Technology Bombay, Mumbai, India
| | - Prashant S Phale
- Department of Biosciences and Bioengineering, Indian Institute of Technology Bombay, Mumbai, India
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12
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Matilla MA, Martín-Mora D, Krell T. The use of isothermal titration calorimetry to unravel chemotactic signalling mechanisms. Environ Microbiol 2020; 22:3005-3019. [PMID: 32329116 DOI: 10.1111/1462-2920.15035] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2020] [Revised: 04/20/2020] [Accepted: 04/21/2020] [Indexed: 12/13/2022]
Abstract
Chemotaxis is based on the action of chemosensory pathways and is typically initiated by the recognition of chemoeffectors at chemoreceptor ligand-binding domains (LBD). Chemosensory signalling is highly complex; aspect that is not only reflected in the intricate interaction between many signalling proteins but also in the fact that bacteria frequently possess multiple chemosensory pathways and often a large number of chemoreceptors, which are mostly of unknown function. We review here the usefulness of isothermal titration calorimetry (ITC) to study this complexity. ITC is the gold standard for studying binding processes due to its precision and sensitivity, as well as its capability to determine simultaneously the association equilibrium constant, enthalpy change and stoichiometry of binding. There is now evidence that members of all major LBD families can be produced as individual recombinant proteins that maintain their ligand-binding properties. High-throughput screening of these proteins using thermal shift assays offer interesting initial information on chemoreceptor ligands, providing the basis for microcalorimetric analyses and microbiological experimentation. ITC has permitted the identification and characterization of many chemoreceptors with novel specificities. This ITC-based approach can also be used to identify signal molecules that stimulate members of other families of sensor proteins.
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Affiliation(s)
- Miguel A Matilla
- Department of Environmental Protection, Estación Experimental del Zaidín, Consejo Superior de Investigaciones Científicas, Granada, Spain
| | - David Martín-Mora
- Department of Environmental Protection, Estación Experimental del Zaidín, Consejo Superior de Investigaciones Científicas, Granada, Spain
| | - Tino Krell
- Department of Environmental Protection, Estación Experimental del Zaidín, Consejo Superior de Investigaciones Científicas, Granada, Spain
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13
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Hybrid Two-Component Sensors for Identification of Bacterial Chemoreceptor Function. Appl Environ Microbiol 2019; 85:AEM.01626-19. [PMID: 31492670 DOI: 10.1128/aem.01626-19] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2019] [Accepted: 08/31/2019] [Indexed: 12/12/2022] Open
Abstract
Soil bacteria adapt to diverse and rapidly changing environmental conditions by sensing and responding to environmental cues using a variety of sensory systems. Two-component systems are a widespread type of signal transduction system present in all three domains of life and typically are comprised of a sensor kinase and a response regulator. Many two-component systems function by regulating gene expression in response to environmental stimuli. The bacterial chemotaxis system is a modified two-component system with additional protein components and a response that, rather than regulating gene expression, involves behavioral adaptation and results in net movement toward or away from a chemical stimulus. Soil bacteria generally have 20 to 40 or more chemoreceptors encoded in their genomes. To simplify the identification of chemoeffectors (ligands) sensed by bacterial chemoreceptors, we constructed hybrid sensor proteins by fusing the sensor domains of Pseudomonas putida chemoreceptors to the signaling domains of the Escherichia coli NarX/NarQ nitrate sensors. Responses to potential attractants were monitored by β-galactosidase assays using an E. coli reporter strain in which the nitrate-responsive narG promoter was fused to lacZ Hybrid receptors constructed from PcaY, McfR, and NahY, which are chemoreceptors for aromatic acids, tricarboxylic acid cycle intermediates, and naphthalene, respectively, were sensitive and specific for detecting known attractants, and the β-galactosidase activities measured in E. coli correlated well with results of chemotaxis assays in the native P. putida strain. In addition, a screen of the hybrid receptors successfully identified new ligands for chemoreceptor proteins and resulted in the identification of six receptors that detect propionate.IMPORTANCE Relatively few of the thousands of chemoreceptors encoded in bacterial genomes have been functionally characterized. More importantly, although methyl-accepting chemotaxis proteins, the major type of chemoreceptors present in bacteria, are easily identified bioinformatically, it is not currently possible to predict what chemicals will bind to a particular chemoreceptor. Chemotaxis is known to play roles in biodegradation as well as in host-pathogen and host-symbiont interactions, but many studies are currently limited by the inability to identify relevant chemoreceptor ligands. The use of hybrid receptors and this simple E. coli reporter system allowed rapid and sensitive screening for potential chemoeffectors. The fusion site chosen for this study resulted in a high percentage of functional hybrids, indicating that it could be used to broadly test chemoreceptor responses from phylogenetically diverse samples. Considering the wide range of chemical attractants detected by soil bacteria, hybrid receptors may also be useful as sensitive biosensors.
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14
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Fernández M, Rico-Jiménez M, Ortega Á, Daddaoua A, García García AI, Martín-Mora D, Torres NM, Tajuelo A, Matilla MA, Krell T. Determination of Ligand Profiles for Pseudomonas aeruginosa Solute Binding Proteins. Int J Mol Sci 2019; 20:ijms20205156. [PMID: 31627455 PMCID: PMC6829864 DOI: 10.3390/ijms20205156] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2019] [Revised: 10/15/2019] [Accepted: 10/16/2019] [Indexed: 01/05/2023] Open
Abstract
Solute binding proteins (SBPs) form a heterogeneous protein family that is found in all kingdoms of life. In bacteria, the ligand-loaded forms bind to transmembrane transporters providing the substrate. We present here the SBP repertoire of Pseudomonas aeruginosa PAO1 that is composed of 98 proteins. Bioinformatic predictions indicate that many of these proteins have a redundant ligand profile such as 27 SBPs for proteinogenic amino acids, 13 proteins for spermidine/putrescine, or 9 proteins for quaternary amines. To assess the precision of these bioinformatic predictions, we have purified 17 SBPs that were subsequently submitted to high-throughput ligand screening approaches followed by isothermal titration calorimetry studies, resulting in the identification of ligands for 15 of them. Experimentation revealed that PA0222 was specific for γ-aminobutyrate (GABA), DppA2 for tripeptides, DppA3 for dipeptides, CysP for thiosulphate, OpuCC for betaine, and AotJ for arginine. Furthermore, RbsB bound D-ribose and D-allose, ModA bound molybdate, tungstate, and chromate, whereas AatJ recognized aspartate and glutamate. The majority of experimentally identified ligands were found to be chemoattractants. Data show that the ligand class recognized by SPBs can be predicted with confidence using bioinformatic methods, but experimental work is necessary to identify the precise ligand profile.
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Affiliation(s)
- Matilde Fernández
- Department of Environmental Protection, Estación Experimental del Zaidín, Consejo Superior de Investigaciones Científicas, 18008 Granada, Spain.
- present address: Department of Microbiology, Faculty of Pharmacy, University of Granada, Campus de Cartuja s/n, 18071 Granada, Spain.
| | - Miriam Rico-Jiménez
- Department of Environmental Protection, Estación Experimental del Zaidín, Consejo Superior de Investigaciones Científicas, 18008 Granada, Spain.
| | - Álvaro Ortega
- Department of Environmental Protection, Estación Experimental del Zaidín, Consejo Superior de Investigaciones Científicas, 18008 Granada, Spain.
| | - Abdelali Daddaoua
- Department of Environmental Protection, Estación Experimental del Zaidín, Consejo Superior de Investigaciones Científicas, 18008 Granada, Spain.
| | - Ana Isabel García García
- Department of Environmental Protection, Estación Experimental del Zaidín, Consejo Superior de Investigaciones Científicas, 18008 Granada, Spain.
| | - David Martín-Mora
- Department of Environmental Protection, Estación Experimental del Zaidín, Consejo Superior de Investigaciones Científicas, 18008 Granada, Spain.
| | - Noel Mesa Torres
- Department of Environmental Protection, Estación Experimental del Zaidín, Consejo Superior de Investigaciones Científicas, 18008 Granada, Spain.
| | - Ana Tajuelo
- Department of Environmental Protection, Estación Experimental del Zaidín, Consejo Superior de Investigaciones Científicas, 18008 Granada, Spain.
| | - Miguel A Matilla
- Department of Environmental Protection, Estación Experimental del Zaidín, Consejo Superior de Investigaciones Científicas, 18008 Granada, Spain.
| | - Tino Krell
- Department of Environmental Protection, Estación Experimental del Zaidín, Consejo Superior de Investigaciones Científicas, 18008 Granada, Spain.
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Chemoperception of Specific Amino Acids Controls Phytopathogenicity in Pseudomonas syringae pv. tomato. mBio 2019; 10:mBio.01868-19. [PMID: 31575767 PMCID: PMC6775455 DOI: 10.1128/mbio.01868-19] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023] Open
Abstract
There is substantive evidence that chemotaxis is a key requisite for efficient pathogenesis in plant pathogens. However, information regarding particular bacterial chemoreceptors and the specific plant signal that they sense is scarce. Our work shows that the phytopathogenic bacterium Pseudomonas syringae pv. tomato mediates not only chemotaxis but also the control of pathogenicity through the perception of the plant abundant amino acids Asp and Glu. We describe the specificity of the perception of l- and d-Asp and l-Glu by the PsPto-PscA chemoreceptor and the involvement of this perception in the regulation of pathogenicity-related traits. Moreover, a saturating concentration of d-Asp reduces bacterial virulence, and we therefore propose that ligand-mediated interference of key chemoreceptors may be an alternative strategy to control virulence. Chemotaxis has been associated with the pathogenicity of bacteria in plants and was found to facilitate bacterial entry through stomata and wounds. However, knowledge regarding the plant signals involved in this process is scarce. We have addressed this issue using Pseudomonas syringae pv. tomato, which is a foliar pathogen that causes bacterial speck in tomato. We show that the chemoreceptor P. syringae pv. tomato PscA (PsPto-PscA) recognizes specifically and with high affinity l-Asp, l-Glu, and d-Asp. The mutation of the chemoreceptor gene largely reduced chemotaxis to these ligands but also altered cyclic di-GMP (c-di-GMP) levels, biofilm formation, and motility, pointing to cross talk between different chemosensory pathways. Furthermore, the PsPto-PscA mutant strain showed reduced virulence in tomato. Asp and Glu are the most abundant amino acids in plants and in particular in tomato apoplasts, and we hypothesize that this receptor may have evolved to specifically recognize these compounds to facilitate bacterial entry into the plant. Infection assays with the wild-type strain showed that the presence of saturating concentrations of d-Asp also reduced bacterial virulence.
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16
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Yang W, Briegel A. Diversity of Bacterial Chemosensory Arrays. Trends Microbiol 2019; 28:68-80. [PMID: 31473052 DOI: 10.1016/j.tim.2019.08.002] [Citation(s) in RCA: 27] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2019] [Revised: 07/15/2019] [Accepted: 08/01/2019] [Indexed: 02/01/2023]
Abstract
Chemotaxis is crucial for the survival of bacteria, and the signaling systems associated with it exhibit a high level of evolutionary conservation. The architecture of the chemosensory array and the signal transduction mechanisms have been extensively studied in Escherichia coli. More recent studies have revealed a vast diversity of the chemosensory system among bacteria. Unlike E. coli, some bacteria assemble more than one chemosensory array and respond to a broader spectrum of environmental and internal stimuli. These chemosensory arrays exhibit a great variability in terms of protein composition, cellular localization, and functional variability. Here, we present recent findings that emphasize the extent of diversity in chemosensory arrays and highlight the importance of studying chemosensory arrays in bacteria other than the common model organisms.
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Affiliation(s)
- Wen Yang
- Institute of Biology, Leiden University, Leiden, The Netherlands
| | - Ariane Briegel
- Institute of Biology, Leiden University, Leiden, The Netherlands.
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17
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Monteagudo-Cascales E, García-Mauriño SM, Santero E, Canosa I. Unraveling the role of the CbrA histidine kinase in the signal transduction of the CbrAB two-component system in Pseudomonas putida. Sci Rep 2019; 9:9110. [PMID: 31235731 PMCID: PMC6591292 DOI: 10.1038/s41598-019-45554-9] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2019] [Accepted: 06/10/2019] [Indexed: 12/24/2022] Open
Abstract
The histidine kinase CbrA of the CbrAB two-component system of Pseudomonas putida is a key element to recognise the activating signal and mediate auto- and trans-phosphorylation of the response element CbrB. CbrA is encoded by the gene cbrA which is located downstream of a putative open reading frame we have named cbrX. We describe the role of the CbrX product in the expression of CbrA and show there is translational coupling of the genes. We also explore the role of the transmembrane (TM) and PAS domains of CbrA in the signal recognition. A ΔcbrXA mutant lacking its TM domains is uncoupled in its growth in histidine and citrate as carbon sources, but its overexpression restores the ability to grow in such carbon sources. In these conditions ΔTM-CbrA is able to respond to carbon availability, thus suggesting an intracellular nature for the signal sensed.
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Affiliation(s)
- Elizabet Monteagudo-Cascales
- Universidad Pablo de Olavide, Centro Andaluz de Biología del Desarrollo/Consejo Superior de Investigaciones Científicas/Junta de Andalucía, Seville, Spain
| | - Sofía M García-Mauriño
- Universidad Pablo de Olavide, Centro Andaluz de Biología del Desarrollo/Consejo Superior de Investigaciones Científicas/Junta de Andalucía, Seville, Spain
| | - Eduardo Santero
- Universidad Pablo de Olavide, Centro Andaluz de Biología del Desarrollo/Consejo Superior de Investigaciones Científicas/Junta de Andalucía, Seville, Spain
| | - Inés Canosa
- Universidad Pablo de Olavide, Centro Andaluz de Biología del Desarrollo/Consejo Superior de Investigaciones Científicas/Junta de Andalucía, Seville, Spain.
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18
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Chemotaxis Towards Aromatic Compounds: Insights from Comamonas testosteroni. Int J Mol Sci 2019; 20:ijms20112701. [PMID: 31159416 PMCID: PMC6600141 DOI: 10.3390/ijms20112701] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2019] [Revised: 05/28/2019] [Accepted: 05/30/2019] [Indexed: 02/07/2023] Open
Abstract
Chemotaxis is an important physiological adaptation that allows many motile bacteria to orientate themselves for better niche adaptation. Chemotaxis is best understood in Escherichia coli. Other representative bacteria, such as Rhodobacter sphaeroides, Pseudomonas species, Helicobacter pylori, and Bacillus subtilis, also have been deeply studied and systemically summarized. These bacteria belong to α-, γ-, ε-Proteobacteria, or Firmicutes. However, β-Proteobacteria, of which many members have been identified as holding chemotactic pathways, lack a summary of chemotaxis. Comamonas testosteroni, belonging to β-Proteobacteria, grows with and chemotactically responds to a range of aromatic compounds. This paper summarizes the latest research on chemotaxis towards aromatic compounds, mainly from investigations of C. testosteroni and other Comamonas species.
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