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Quiroz Monnens T, Boulanger A. A large scale bacterial attraction assay: A new quantitative bacterial migration assay suitable for genetic screens. PLoS One 2024; 19:e0305037. [PMID: 38837976 DOI: 10.1371/journal.pone.0305037] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2024] [Accepted: 05/22/2024] [Indexed: 06/07/2024] Open
Abstract
Bacteria use various motility mechanisms to explore their environments. Chemotaxis is the ability of a motile bacterial cell to direct its movement in response to chemical gradients. A number of methods have been developed and widely used to study chemotactic responses to chemoeffectors including capillary, agar plug, microscopic slide, and microfluidic assays. While valuable, these assays are primarily designed to monitor rapid chemotactic responses to chemoeffectors on a small scale, which poses challenges in collecting large quantities of attracted bacteria. Consequently, these setups are not ideal for experiments like forward genetic screens. To overcome this limitation, we developed the Large Scale Bacterial Attraction assay (LSBA), which relies on the use of a Nalgene™ Reusable Filter Unit and other materials commonly found in laboratories. We validate the LSBA by investigating chemoeffector kinetics in the setup and by using chemoattractants to quantify the chemotactic response of wild-type, and motility impaired strains of the plant pathogenic bacterium Xanthomonas campestris pv. campestris and the environmental bacterium Shewanella oneidensis. We show that the LSBA establishes a long lasting chemoeffector gradient, that the setup can be used to quantify bacterial migration over time and that the LSBA offers the possibility to collect high numbers of attracted bacteria, making it suitable for genetic screens.
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Affiliation(s)
- Thomas Quiroz Monnens
- LIPME, INRAE, CNRS, Université de Toulouse, Université Paul Sabatier, Castanet-Tolosan, France
| | - Alice Boulanger
- LIPME, INRAE, CNRS, Université de Toulouse, Université Paul Sabatier, Castanet-Tolosan, France
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2
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Cerna-Vargas JP, Gumerov VM, Krell T, Zhulin IB. Amine-recognizing domain in diverse receptors from bacteria and archaea evolved from the universal amino acid sensor. Proc Natl Acad Sci U S A 2023; 120:e2305837120. [PMID: 37819981 PMCID: PMC10589655 DOI: 10.1073/pnas.2305837120] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2023] [Accepted: 09/09/2023] [Indexed: 10/13/2023] Open
Abstract
Bacteria possess various receptors that sense different signals and transmit information to enable an optimal adaptation to the environment. A major limitation in microbiology is the lack of information on the signal molecules that activate receptors. Signals recognized by sensor domains are poorly reflected in overall sequence identity, and therefore, the identification of signals from the amino acid sequence of the sensor alone presents a challenge. Biogenic amines are of great physiological importance for microorganisms and humans. They serve as substrates for aerobic and anaerobic growth and play a role of neurotransmitters and osmoprotectants. Here, we report the identification of a sequence motif that is specific for amine-sensing sensor domains that belong to the Cache superfamily of the most abundant extracellular sensors in prokaryotes. We identified approximately 13,000 sensor histidine kinases, chemoreceptors, receptors involved in second messenger homeostasis and Ser/Thr phosphatases from 8,000 bacterial and archaeal species that contain the amine-recognizing motif. The screening of compound libraries and microcalorimetric titrations of selected sensor domains confirmed their ability to specifically bind biogenic amines. Mutants in the amine-binding motif or domains that contain a single mismatch in the binding motif had either no or a largely reduced affinity for amines. We demonstrate that the amine-recognizing domain originated from the universal amino acid-sensing Cache domain, thus providing insight into receptor evolution. Our approach enables precise "wet"-lab experiments to define the function of regulatory systems and therefore holds a strong promise to enable the identification of signals stimulating numerous receptors.
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Affiliation(s)
- Jean Paul Cerna-Vargas
- Department of Biotechnology and Environmental Protection, Estación Experimental del Zaidín, Consejo Superior de Investigaciones Científicas, Granada18008, Spain
- Centro de Biotecnología y Genómica de Plantas, Universidad Politécnica de Madrid Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria/Consejo Superior de Investigaciones Científicas, Parque Científico y Tecnológico de la Universidad Politécnica de Madrid, Pozuelo de Alarcón, Madrid28223, Spain
| | - Vadim M. Gumerov
- Department of Microbiology and Translational Data Analytics Institute, The Ohio State University, Columbus, OH43210
| | - Tino Krell
- Department of Biotechnology and Environmental Protection, Estación Experimental del Zaidín, Consejo Superior de Investigaciones Científicas, Granada18008, Spain
| | - Igor B. Zhulin
- Department of Microbiology and Translational Data Analytics Institute, The Ohio State University, Columbus, OH43210
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3
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Cerna‐Vargas JP, Sánchez‐Romera B, Matilla MA, Ortega Á, Krell T. Sensing preferences for prokaryotic solute binding protein families. Microb Biotechnol 2023; 16:1823-1833. [PMID: 37547952 PMCID: PMC10443332 DOI: 10.1111/1751-7915.14292] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2023] [Accepted: 05/25/2023] [Indexed: 08/08/2023] Open
Abstract
Solute binding proteins (SBPs) are of central physiological relevance for prokaryotes. These proteins present substrates to transporters, but they also stimulate different signal transduction receptors. SBPs form a superfamily of at least 33 protein Pfam families. To assess possible links between SBP sequence and the ligand recognized, we have inspected manually all SBP three-dimensional structures deposited in the protein data bank and retrieved 748 prokaryotic structures that have been solved in complex with bound ligand. These structures were classified into 26 SBP Pfam families. The analysis of the ligands recognized revealed that most families possess a preference for a compound class. There were three families each that bind preferentially saccharides and amino acids. In addition, we identified families that bind preferentially purines, quaternary amines, iron and iron-chelating compounds, oxoanions, bivalent metal ions or phosphates. Phylogenetic analyses suggest convergent evolutionary events that lead to families that bind the same ligand. The functional link between chemotaxis and compound uptake is reflected in similarities in the ligands recognized by SBPs and chemoreceptors. Associating Pfam families with ligand profiles will be of help to design experimental strategies aimed at the identification of ligands for uncharacterized SBPs.
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Affiliation(s)
- Jean Paul Cerna‐Vargas
- Department of Biotechnology and Environmental ProtectionEstación Experimental del Zaidín, Consejo Superior de Investigaciones CientíficasGranadaSpain
- 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 UPMMadridSpain
| | - Beatriz Sánchez‐Romera
- Scientific Instrumentation ServiceEstación Experimental del Zaidín, Consejo Superior de Investigaciones CientíficasGranadaSpain
| | - Miguel A. Matilla
- Department of Biotechnology and Environmental ProtectionEstación Experimental del Zaidín, Consejo Superior de Investigaciones CientíficasGranadaSpain
| | - Álvaro Ortega
- Department of Biochemistry and Molecular Biology B and Immunology, Faculty of ChemistryUniversity of MurciaMurciaSpain
| | - Tino Krell
- Department of Biotechnology and Environmental ProtectionEstación Experimental del Zaidín, Consejo Superior de Investigaciones CientíficasGranadaSpain
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4
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Cerna-Vargas JP, Gumerov VM, Krell T, Zhulin IB. Amine recognizing domain in diverse receptors from bacteria and archaea evolved from the universal amino acid sensor. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.04.06.535858. [PMID: 37066253 PMCID: PMC10104139 DOI: 10.1101/2023.04.06.535858] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Indexed: 06/19/2023]
Abstract
Bacteria contain many different receptor families that sense different signals permitting an optimal adaptation to the environment. A major limitation in microbiology is the lack of information on the signal molecules that activate receptors. Due to a significant sequence divergence, the signal recognized by sensor domains is only poorly reflected in overall sequence identity. Biogenic amines are of central physiological relevance for microorganisms and serve for example as substrates for aerobic and anaerobic growth, neurotransmitters or osmoprotectants. Based on protein structural information and sequence analysis, we report here the identification of a sequence motif that is specific for amine-sensing dCache sensor domains (dCache_1AM). These domains were identified in more than 13,000 proteins from 8,000 bacterial and archaeal species. dCache_1AM containing receptors were identified in all major receptor families including sensor kinases, chemoreceptors, receptors involved in second messenger homeostasis and Ser/Thr phosphatases. The screening of compound libraries and microcalorimetric titrations of selected dCache_1AM domains confirmed their capacity to specifically bind amines. Mutants in the amine binding motif or domains that contain a single mismatch in the binding motif, had either no or a largely reduced affinity for amines, illustrating the specificity of this motif. We demonstrate that the dCache_1AM domain has evolved from the universal amino acid sensing domain, providing novel insight into receptor evolution. Our approach enables precise "wet"-lab experiments to define the function of regulatory systems and thus holds a strong promise to address an important bottleneck in microbiology: the identification of signals that stimulate numerous receptors.
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Affiliation(s)
- Jean Paul Cerna-Vargas
- Department of Biotechnology and Environmental Protection, Estación Experimental del Zaidín, Consejo Superior de Investigaciones Científicas, Prof. Albareda 1, 18008 Granada, Spain
- 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
| | - Vadim M. Gumerov
- Department of Microbiology and Translational Data Analytics Institute, The Ohio State University, Columbus, OH 43210, USA
| | - Tino Krell
- Department of Biotechnology and Environmental Protection, Estación Experimental del Zaidín, Consejo Superior de Investigaciones Científicas, Prof. Albareda 1, 18008 Granada, Spain
| | - Igor B. Zhulin
- Department of Microbiology and Translational Data Analytics Institute, The Ohio State University, Columbus, OH 43210, USA
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5
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Matilla MA, Genova R, Martín-Mora D, Maaβ S, Becher D, Krell T. The Cellular Abundance of Chemoreceptors, Chemosensory Signaling Proteins, Sensor Histidine Kinases, and Solute Binding Proteins of Pseudomonas aeruginosa Provides Insight into Sensory Preferences and Signaling Mechanisms. Int J Mol Sci 2023; 24:ijms24021363. [PMID: 36674894 PMCID: PMC9864684 DOI: 10.3390/ijms24021363] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2022] [Revised: 12/21/2022] [Accepted: 12/24/2022] [Indexed: 01/12/2023] Open
Abstract
Chemosensory pathways and two-component systems are important bacterial signal transduction systems. In the human pathogen Pseudomonas aeruginosa, these systems control many virulence traits. Previous studies showed that inorganic phosphate (Pi) deficiency induces virulence. We report here the abundance of chemosensory and two-component signaling proteins of P. aeruginosa grown in Pi deficient and sufficient media. The cellular abundance of chemoreceptors differed greatly, since a 2400-fold difference between the most and least abundant receptors was observed. For many chemoreceptors, their amount varied with the growth condition. The amount of chemoreceptors did not correlate with the magnitude of chemotaxis to their cognate chemoeffectors. Of the four chemosensory pathways, proteins of the Che chemotaxis pathway were most abundant and showed little variation in different growth conditions. The abundance of chemoreceptors and solute binding proteins indicates a sensing preference for amino acids and polyamines. There was an excess of response regulators over sensor histidine kinases in two-component systems. In contrast, ratios of the response regulators CheY and CheB to the histidine kinase CheA of the Che pathway were all below 1, indicative of different signaling mechanisms. This study will serve as a reference for exploring sensing preferences and signaling mechanisms of other bacteria.
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Affiliation(s)
- Miguel A. Matilla
- Department of Biotechnology and Environmental Protection, Estación Experimental del Zaidín, Consejo Superior de Investigaciones Científicas, 18008 Granada, Spain
| | - Roberta Genova
- Department of Biotechnology and Environmental Protection, Estación Experimental del Zaidín, Consejo Superior de Investigaciones Científicas, 18008 Granada, Spain
| | - David Martín-Mora
- Department of Biotechnology and Environmental Protection, Estación Experimental del Zaidín, Consejo Superior de Investigaciones Científicas, 18008 Granada, Spain
| | - Sandra Maaβ
- Department of Microbial Proteomics, Institute of Microbiology, University of Greifswald, D-17489 Greifswald, Germany
| | - Dörte Becher
- Department of Microbial Proteomics, Institute of Microbiology, University of Greifswald, D-17489 Greifswald, Germany
| | - Tino Krell
- Department of Biotechnology and Environmental Protection, Estación Experimental del Zaidín, Consejo Superior de Investigaciones Científicas, 18008 Granada, Spain
- Correspondence: ; Tel.: +34-958-526579
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6
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Defining Two Chemosensory Arrays in Shewanella oneidensis. Biomolecules 2022; 13:biom13010021. [PMID: 36671406 PMCID: PMC9855816 DOI: 10.3390/biom13010021] [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: 12/15/2022] [Accepted: 12/16/2022] [Indexed: 12/24/2022] Open
Abstract
Shewanella oneidensis has 2 functional chemosensory systems named Che1 and Che3, and 27 chemoreceptors. Che3 is dedicated to chemotaxis while Che1 could be involved in RpoS post-translational regulation. In this study, we have shown that two chemoreceptors Aer2so and McpAso, genetically related to the Che1 system, form distinct core-signaling units and signal to Che1 and Che3, respectively. Moreover, we observed that Aer2so is a cytoplasmic dynamic chemoreceptor that, when in complex with CheA1 and CheW1, localizes at the two poles and the centre of the cells. Altogether, the results obtained indicate that Che1 and Che3 systems are interconnected by these two chemoreceptors allowing a global response for bacterial survival.
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Boyeldieu A, Poli J, Ali Chaouche A, Fierobe H, Giudici‐Orticoni M, Méjean V, Jourlin‐Castelli C. Multiple detection of both attractants and repellents by the dCache-chemoreceptor SO_1056 of Shewanella oneidensis. FEBS J 2022; 289:6752-6766. [PMID: 35668695 PMCID: PMC9796306 DOI: 10.1111/febs.16548] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2022] [Revised: 05/17/2022] [Accepted: 06/06/2022] [Indexed: 01/01/2023]
Abstract
Chemoreceptors are usually transmembrane proteins dedicated to the detection of compound gradients or signals in the surroundings of a bacterium. After detection, they modulate the activation of CheA-CheY, the core of the chemotactic pathway, to allow cells to move upwards or downwards depending on whether the signal is an attractant or a repellent, respectively. Environmental bacteria such as Shewanella oneidensis harbour dozens of chemoreceptors or MCPs (methyl-accepting chemotaxis proteins). A recent study revealed that MCP SO_1056 of S. oneidensis binds chromate. Here, we show that this MCP also detects an additional attractant (l-malate) and two repellents (nickel and cobalt). The experiments were performed in vivo by the agarose-in-plug technique after overproducing MCP SO_1056 and in vitro, when possible, by submitting the purified ligand-binding domain (LBD) of SO_1056 to a thermal shift assay (TSA) coupled to isothermal titration calorimetry (ITC). ITC assays revealed a KD of 3.4 μm for l-malate and of 47.7 μm for nickel. We conclude that MCP SO_1056 binds attractants and repellents of unrelated composition. The LBD of SO_1056 belongs to the double Cache_1 family and is highly homologous to PctA, a chemoreceptor from Pseudomonas aeruginosa that detects several amino acids. Therefore, LBDs of the same family can bind diverse compounds, confirming that experimental approaches are required to define accurate LBD-binding molecules or signals.
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Affiliation(s)
- Anne Boyeldieu
- Laboratoire de Bioénergétique et Ingénierie des Protéines (BIP, UMR7281), Centre National de la Recherche Scientifique, Institut de Microbiologie de la Méditerranée (IMM), Institut Microbiologie, Bioénergies et Biotechnologie (IM2B)Aix Marseille UniversitéFrance,Present address:
Laboratoire de Microbiologie et de Génétique Moléculaires, UMR5100, Centre de Biologie Intégrative (CBI), Centre National de la Recherche Scientifique (CNRS)Université de Toulouse, UPSFrance
| | - Jean‐Pierre Poli
- Laboratoire de Bioénergétique et Ingénierie des Protéines (BIP, UMR7281), Centre National de la Recherche Scientifique, Institut de Microbiologie de la Méditerranée (IMM), Institut Microbiologie, Bioénergies et Biotechnologie (IM2B)Aix Marseille UniversitéFrance,Université de Corse Pasquale PaoliCorteFrance
| | - Amine Ali Chaouche
- Laboratoire de Bioénergétique et Ingénierie des Protéines (BIP, UMR7281), Centre National de la Recherche Scientifique, Institut de Microbiologie de la Méditerranée (IMM), Institut Microbiologie, Bioénergies et Biotechnologie (IM2B)Aix Marseille UniversitéFrance
| | - Henri‐Pierre Fierobe
- Laboratoire de Chimie Bactérienne (LCB, UMR7283), Centre National de la Recherche Scientifique, Institut de Microbiologie de la Méditerranée (IMM), Institut Microbiologie, Bioénergies et Biotechnologie (IM2B)Aix Marseille UniversitéFrance
| | - Marie‐Thérèse Giudici‐Orticoni
- Laboratoire de Bioénergétique et Ingénierie des Protéines (BIP, UMR7281), Centre National de la Recherche Scientifique, Institut de Microbiologie de la Méditerranée (IMM), Institut Microbiologie, Bioénergies et Biotechnologie (IM2B)Aix Marseille UniversitéFrance
| | - Vincent Méjean
- Laboratoire de Bioénergétique et Ingénierie des Protéines (BIP, UMR7281), Centre National de la Recherche Scientifique, Institut de Microbiologie de la Méditerranée (IMM), Institut Microbiologie, Bioénergies et Biotechnologie (IM2B)Aix Marseille UniversitéFrance
| | - Cécile Jourlin‐Castelli
- Laboratoire de Bioénergétique et Ingénierie des Protéines (BIP, UMR7281), Centre National de la Recherche Scientifique, Institut de Microbiologie de la Méditerranée (IMM), Institut Microbiologie, Bioénergies et Biotechnologie (IM2B)Aix Marseille UniversitéFrance
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Comparative Genomics of Cyclic di-GMP Metabolism and Chemosensory Pathways in Shewanella algae Strains: Novel Bacterial Sensory Domains and Functional Insights into Lifestyle Regulation. mSystems 2022; 7:e0151821. [PMID: 35311563 PMCID: PMC9040814 DOI: 10.1128/msystems.01518-21] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
Shewanella spp. play important ecological and biogeochemical roles, due in part to their versatile metabolism and swift integration of stimuli. While Shewanella spp. are primarily considered environmental microbes, Shewanella algae is increasingly recognized as an occasional human pathogen. S. algae shares the broad metabolic and respiratory repertoire of Shewanella spp. and thrives in similar ecological niches. In S. algae, nitrate and dimethyl sulfoxide (DMSO) respiration promote biofilm formation strain specifically, with potential implication of taxis and cyclic diguanosine monophosphate (c-di-GMP) signaling. Signal transduction systems in S. algae have not been investigated. To fill these knowledge gaps, we provide here an inventory of the c-di-GMP turnover proteome and chemosensory networks of the type strain S. algae CECT 5071 and compare them with those of 41 whole-genome-sequenced clinical and environmental S. algae isolates. Besides comparative analysis of genetic content and identification of laterally transferred genes, the occurrence and topology of c-di-GMP turnover proteins and chemoreceptors were analyzed. We found S. algae strains to encode 61 to 67 c-di-GMP turnover proteins and 28 to 31 chemoreceptors, placing S. algae near the top in terms of these signaling capacities per Mbp of genome. Most c-di-GMP turnover proteins were predicted to be catalytically active; we describe in them six novel N-terminal sensory domains that appear to control their catalytic activity. Overall, our work defines the c-di-GMP and chemosensory signal transduction pathways in S. algae, contributing to a better understanding of its ecophysiology and establishing S. algae as an auspicious model for the analysis of metabolic and signaling pathways within the genus Shewanella. IMPORTANCEShewanella spp. are widespread aquatic bacteria that include the well-studied freshwater model strain Shewanella oneidensis MR-1. In contrast, the physiology of the marine and occasionally pathogenic species Shewanella algae is poorly understood. Chemosensory and c-di-GMP signal transduction systems integrate environmental stimuli to modulate gene expression, including the switch from a planktonic to sessile lifestyle and pathogenicity. Here, we systematically dissect the c-di-GMP proteome and chemosensory pathways of the type strain S. algae CECT 5071 and 41 additional S. algae isolates. We provide insights into the activity and function of these proteins, including a description of six novel sensory domains. Our work will enable future analyses of the complex, intertwined c-di-GMP metabolism and chemotaxis networks of S. algae and their ecophysiological role.
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A Review of the Advantages, Disadvantages and Limitations of Chemotaxis Assays for Campylobacter spp. Int J Mol Sci 2022; 23:ijms23031576. [PMID: 35163499 PMCID: PMC8836060 DOI: 10.3390/ijms23031576] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2021] [Revised: 01/27/2022] [Accepted: 01/27/2022] [Indexed: 11/26/2022] Open
Abstract
Reproducible qualitative and quantitative assessment of bacterial chemotactic motility, particularly in response to chemorepellent effectors, is experimentally challenging. Here we compare several established chemotaxis assays currently used to investigate Campylobacter jejuni chemotaxis, with the aim of improving the correlation between different studies and establishing the best practices. We compare the methodologies of capillary, agar, and chamber-based assays, and discuss critical technical points, in terms of reproducibility, accuracy, and the advantages and limitations of each.
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Wang H, Zhang M, Xu Y, Zong R, Xu N, Guo M. Agrobacterium fabrum atu0526-Encoding Protein Is the Only Chemoreceptor That Regulates Chemoattraction toward the Broad Antibacterial Agent Formic Acid. BIOLOGY 2021; 10:biology10121345. [PMID: 34943260 PMCID: PMC8698456 DOI: 10.3390/biology10121345] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/28/2021] [Revised: 12/11/2021] [Accepted: 12/13/2021] [Indexed: 12/25/2022]
Abstract
Soil-born plant pathogens, especially Agrobacterium, generally navigate their way to hosts through recognition of the root exudates by chemoreceptors. However, there is still a lack of appropriate identification of chemoreceptors and their ligands in Agrobacterium. Here, Atu0526, a sCache-type chemoreceptor from Agrobacterium fabrum C58, was confirmed as the receptor of a broad antibacterial agent, formic acid. The binding of formic acid to Atu0526 was screened using a thermo shift assay and verified using isothermal titration calorimetry. Inconsistent with the previously reported antimicrobial properties, formic acid was confirmed to be a chemoattractant to A. fabrum and could promote its growth. The chemotaxis of A. fabrum C58 toward formic acid was completely lost with the knock-out of atu0526, and regained with the complementation of the gene, indicating that Atu0526 is the only chemoreceptor for formic acid in A. fabrum C58. The affinity of formic acid to Atu0526LBD significantly increased after the arginine at position 115 was replaced by alanine. However, in vivo experiments showed that the R115A mutation fully abolished the chemotaxis of A. fabrum toward formic acid. Molecular docking based on a predicted 3D structure of Atu0526 suggested that the arginine may provide "an anchorage" for formic acid to pull the minor loop, thereby forming a conformational change that generates the ligand-binding signal. Collectively, our findings will promote an understanding of sCache-type chemoreceptors and their signal transduction mechanism.
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11
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Colin R, Ni B, Laganenka L, Sourjik V. Multiple functions of flagellar motility and chemotaxis in bacterial physiology. FEMS Microbiol Rev 2021; 45:fuab038. [PMID: 34227665 PMCID: PMC8632791 DOI: 10.1093/femsre/fuab038] [Citation(s) in RCA: 90] [Impact Index Per Article: 30.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2021] [Accepted: 07/02/2021] [Indexed: 12/13/2022] Open
Abstract
Most swimming bacteria are capable of following gradients of nutrients, signaling molecules and other environmental factors that affect bacterial physiology. This tactic behavior became one of the most-studied model systems for signal transduction and quantitative biology, and underlying molecular mechanisms are well characterized in Escherichia coli and several other model bacteria. In this review, we focus primarily on less understood aspect of bacterial chemotaxis, namely its physiological relevance for individual bacterial cells and for bacterial populations. As evident from multiple recent studies, even for the same bacterial species flagellar motility and chemotaxis might serve multiple roles, depending on the physiological and environmental conditions. Among these, finding sources of nutrients and more generally locating niches that are optimal for growth appear to be one of the major functions of bacterial chemotaxis, which could explain many chemoeffector preferences as well as flagellar gene regulation. Chemotaxis might also generally enhance efficiency of environmental colonization by motile bacteria, which involves intricate interplay between individual and collective behaviors and trade-offs between growth and motility. Finally, motility and chemotaxis play multiple roles in collective behaviors of bacteria including swarming, biofilm formation and autoaggregation, as well as in their interactions with animal and plant hosts.
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Affiliation(s)
- Remy Colin
- Max Planck Institute for Terrestrial Microbiology & Center for Synthetic Microbiology (SYNMIKRO), Karl-von-Frisch Strasse 16, Marburg D-35043, Germany
| | - Bin Ni
- Max Planck Institute for Terrestrial Microbiology & Center for Synthetic Microbiology (SYNMIKRO), Karl-von-Frisch Strasse 16, Marburg D-35043, Germany
- College of Resources and Environmental Science, National Academy of Agriculture Green Development, China Agricultural University, Yuanmingyuan Xilu No. 2, Beijing 100193, China
| | - Leanid Laganenka
- Institute of Microbiology, D-BIOL, ETH Zürich, Vladimir-Prelog-Weg 4, Zürich 8093, Switzerland
| | - Victor Sourjik
- Max Planck Institute for Terrestrial Microbiology & Center for Synthetic Microbiology (SYNMIKRO), Karl-von-Frisch Strasse 16, Marburg D-35043, Germany
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12
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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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