1
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Caulton SG, Lambert C, Tyson J, Radford P, Al-Bayati A, Greenwood S, Banks EJ, Clark C, Till R, Pires E, Sockett RE, Lovering AL. Bdellovibrio bacteriovorus uses chimeric fibre proteins to recognize and invade a broad range of bacterial hosts. Nat Microbiol 2024; 9:214-227. [PMID: 38177296 PMCID: PMC10769870 DOI: 10.1038/s41564-023-01552-2] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2023] [Accepted: 11/07/2023] [Indexed: 01/06/2024]
Abstract
Predatory bacteria, like the model endoperiplasmic bacterium Bdellovibrio bacteriovorus, show several adaptations relevant to their requirements for locating, entering and killing other bacteria. The mechanisms underlying prey recognition and handling remain obscure. Here we use complementary genetic, microscopic and structural methods to address this deficit. During invasion, the B. bacteriovorus protein CpoB concentrates into a vesicular compartment that is deposited into the prey periplasm. Proteomic and structural analyses of vesicle contents reveal several fibre-like proteins, which we name the mosaic adhesive trimer (MAT) superfamily, and show localization on the predator surface before prey encounter. These dynamic proteins indicate a variety of binding capabilities, and we confirm that one MAT member shows specificity for surface glycans from a particular prey. Our study shows that the B. bacteriovorus MAT protein repertoire enables a broad means for the recognition and handling of diverse prey epitopes encountered during bacterial predation and invasion.
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Affiliation(s)
- Simon G Caulton
- School of Biosciences, University of Birmingham, Birmingham, UK
| | - Carey Lambert
- School of Life Sciences, University of Nottingham, Medical School, Queen's Medical Centre, Nottingham, UK
- Biodiscovery Institute, School of Life Sciences, Nottingham University, Nottingham, UK
| | - Jess Tyson
- School of Life Sciences, University of Nottingham, Medical School, Queen's Medical Centre, Nottingham, UK
| | - Paul Radford
- School of Life Sciences, University of Nottingham, Medical School, Queen's Medical Centre, Nottingham, UK
| | - Asmaa Al-Bayati
- School of Life Sciences, University of Nottingham, Medical School, Queen's Medical Centre, Nottingham, UK
- Northern Technical University, Kirkuk, Iraq
| | - Samuel Greenwood
- School of Life Sciences, University of Nottingham, Medical School, Queen's Medical Centre, Nottingham, UK
| | - Emma J Banks
- School of Life Sciences, University of Nottingham, Medical School, Queen's Medical Centre, Nottingham, UK
- Department of Molecular Microbiology, John Innes Centre, Norwich, UK
| | - Callum Clark
- School of Life Sciences, University of Nottingham, Medical School, Queen's Medical Centre, Nottingham, UK
- Institute of Microbiology and Infection, University of Birmingham, Birmingham, UK
| | - Rob Till
- School of Life Sciences, University of Nottingham, Medical School, Queen's Medical Centre, Nottingham, UK
| | - Elisabete Pires
- Chemistry Research Laboratory, University of Oxford, Oxford, UK
| | - R Elizabeth Sockett
- School of Life Sciences, University of Nottingham, Medical School, Queen's Medical Centre, Nottingham, UK.
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2
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Caulton SG, Lovering AL. Moving toward a better understanding of the model bacterial predator Bdellovibrio bacteriovorus. MICROBIOLOGY (READING, ENGLAND) 2023; 169:001380. [PMID: 37535060 PMCID: PMC10482364 DOI: 10.1099/mic.0.001380] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/10/2023] [Accepted: 07/27/2023] [Indexed: 08/04/2023]
Abstract
The bacterial predator Bdellovibrio bacteriovorus is a model for the wider phenomenon of bacteria:bacteria predation, and the specialization required to achieve a lifestyle dependent on prey consumption. Bdellovibrio bacteriovorus is able to recognize, enter and ultimately consume fellow Gram-negative bacteria, killing these prey from within their periplasmic space, and lysing the host at the end of the cycle. The classic phenotype-driven characterization (and observation of predation) has benefitted from an increased focus on molecular mechanisms and fluorescence microscopy and tomography, revealing new features of several of the lifecycle stages. Herein we summarize a selection of these advances and describe likely areas for exploration that will push the field toward a more complete understanding of this fascinating 'two-cell' system.
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Affiliation(s)
- Simon G. Caulton
- School of Biosciences, University of Birmingham, Birmingham B15 2TT, UK
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3
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Sockett RE. Learning with Bdellovibrio. Nat Microbiol 2023:10.1038/s41564-023-01417-8. [PMID: 37391456 DOI: 10.1038/s41564-023-01417-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/02/2023]
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4
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Lai TF, Ford RM, Huwiler SG. Advances in cellular and molecular predatory biology of Bdellovibrio bacteriovorus six decades after discovery. Front Microbiol 2023; 14:1168709. [PMID: 37256055 PMCID: PMC10225642 DOI: 10.3389/fmicb.2023.1168709] [Citation(s) in RCA: 9] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2023] [Accepted: 04/14/2023] [Indexed: 06/01/2023] Open
Abstract
Since its discovery six decades ago, the predatory bacterium Bdellovibrio bacteriovorus has sparked recent interest as a potential remedy to the antibiotic resistance crisis. Here we give a comprehensive historical overview from discovery to progressive developments in microscopy and molecular mechanisms. Research on B. bacteriovorus has moved from curiosity to a new model organism, revealing over time more details on its physiology and fascinating predatory life cycle with the help of a variety of methods. Based on recent findings in cryo-electron tomography, we recapitulate on the intricate molecular details known in the predatory life cycle including how this predator searches for its prey bacterium, to how it attaches, grows, and divides all from within the prey cell. Finally, the newly developed B. bacteriovorus progeny leave the prey cell remnants in the exit phase. While we end with some unanswered questions remaining in the field, new imaging technologies and quantitative, systematic advances will likely help to unravel them in the next decades.
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Affiliation(s)
- Ting F. Lai
- Department of Plant and Microbial Biology, University of Zurich, Zurich, Switzerland
| | - Rhian M. Ford
- School of Biosciences, University of Nottingham, Loughborough, United Kingdom
| | - Simona G. Huwiler
- Department of Plant and Microbial Biology, University of Zurich, Zurich, Switzerland
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5
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Dörr T. Cleave a Septum, Leave a Cell: Bdellovibrio bacteriovorus Secretes a Specialized Lytic Transglycosylase to Clear Prey Cell Septum Obstruction. J Bacteriol 2023; 205:e0007423. [PMID: 37010280 PMCID: PMC10128895 DOI: 10.1128/jb.00074-23] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/04/2023] Open
Abstract
Predatory microbes like Bdellovibrio feed on other bacteria by invading their periplasm, replicating within the bacterial shell that is now a feeding trough, and ultimately lysing the prey and disseminating. A new study by E. J. Banks, C. Lambert, S. Mason, J. Tyson, et al. (J Bacteriol 205:e00475-22, 2023, https://doi.org/10.1128/jb.00475-22) highlights the great lengths to which Bdellovibrio must go to affect host cell remodeling: A secreted cell wall lytic enzyme with specificity for the host septal cell wall maximizes the size of the attacker's meal and the size of the restaurant in which it can spread out. This study provides novel insights into bacterial predator-prey dynamics and showcases elegant co-option of an endogenous cell wall turnover enzyme refurbished as a warhead to enhance prey consumption.
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Affiliation(s)
- Tobias Dörr
- Weill Institute for Cell and Molecular Biology, Cornell University, Ithaca, New York, USA
- Department of Microbiology, Cornell University, Ithaca, New York, USA
- Cornell Institute of Host-Microbe Interactions and Disease, Cornell University, Ithaca, New York, USA
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6
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Helminiak L, Mishra S, Keun Kim H. Pathogenicity and virulence of Rickettsia. Virulence 2022; 13:1752-1771. [PMID: 36208040 PMCID: PMC9553169 DOI: 10.1080/21505594.2022.2132047] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2022] [Revised: 09/16/2022] [Accepted: 09/29/2022] [Indexed: 12/24/2022] Open
Abstract
Rickettsiae include diverse Gram-negative microbial species that exhibit obligatory intracellular lifecycles between mammalian hosts and arthropod vectors. Human infections with arthropod-borne Rickettsia continue to cause significant morbidity and mortality as recent environmental changes foster the proliferation of arthropod vectors and increased exposure to humans. However, the technical difficulties in working with Rickettsia have delayed our progress in understanding the molecular mechanisms involved in rickettsial pathogenesis and disease transmission. Recent advances in developing genetic tools for Rickettsia have enabled investigators to identify virulence genes, uncover molecular functions, and characterize host responses to rickettsial determinants. Therefore, continued efforts to determine virulence genes and their biological functions will help us understand the underlying mechanisms associated with arthropod-borne rickettsioses.
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Affiliation(s)
| | | | - Hwan Keun Kim
- Center for Infectious Diseases, Department of Microbiology and Immunology, Stony Brook University, Stony Brook, NY, USA
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7
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Clinton NA, Hameed SA, Agyei EK, Jacob JC, Oyebanji VO, Jabea CE. Crosstalk between the Intestinal Virome and Other Components of the Microbiota, and Its Effect on Intestinal Mucosal Response and Diseases. J Immunol Res 2022; 2022:7883945. [PMID: 36203793 PMCID: PMC9532165 DOI: 10.1155/2022/7883945] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2022] [Revised: 09/12/2022] [Accepted: 09/14/2022] [Indexed: 11/17/2022] Open
Abstract
In recent years, there has been ample evidence illustrating the effect of microbiota on gut immunity, homeostasis, and disease. Most of these studies have engaged more efforts in understanding the role of the bacteriome in gut mucosal immunity and disease. However, studies on the virome and its influence on gut mucosal immunity and pathology are still at infancy owing to limited metagenomic tools. Nonetheless, the existing studies on the virome have largely been focused on the bacteriophages as these represent the main component of the virome with little information on endogenous retroviruses (ERVs) and eukaryotic viruses. In this review, we describe the gut virome, and its role in gut mucosal response and disease progression. We also explore the crosstalk between the virome and other microorganisms in the gut mucosa and elaborate on how these interactions shape the gut mucosal immunity going from bacteriophages through ERVs to eukaryotic viruses. Finally, we elucidate the potential contribution of this crosstalk in the pathogenesis of inflammatory bowel diseases and colon cancer.
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Affiliation(s)
- Njinju Asaba Clinton
- Health and Empowerment Foundation, Cameroon
- Mbonge District Hospital, Cameroon
- University of Buea, Cameroon
| | | | - Eugene Kusi Agyei
- Faculty of Pharmacy and Pharmaceutical Sciences, Kwame Nkrumah University of Science and Technology, Ghana
| | | | | | - Cyril Ekabe Jabea
- Health and Empowerment Foundation, Cameroon
- Mbonge District Hospital, Cameroon
- University of Buea, Cameroon
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8
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The Ankyrin Repeat Protein RARP-1 Is a Periplasmic Factor That Supports Rickettsia parkeri Growth and Host Cell Invasion. J Bacteriol 2022; 204:e0018222. [PMID: 35727033 DOI: 10.1128/jb.00182-22] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Rickettsia spp. are obligate intracellular bacterial pathogens that have evolved a variety of strategies to exploit their host cell niche. However, the bacterial factors that contribute to this intracellular lifestyle are poorly understood. Here, we show that the conserved ankyrin repeat protein RARP-1 supports Rickettsia parkeri infection. Specifically, RARP-1 promotes efficient host cell entry and growth within the host cytoplasm, but it is not necessary for cell-to-cell spread or evasion of host autophagy. We further demonstrate that RARP-1 is not secreted into the host cytoplasm by R. parkeri. Instead, RARP-1 resides in the periplasm, and we identify several binding partners that are predicted to work in concert with RARP-1 during infection. Altogether, our data reveal that RARP-1 plays a critical role in the rickettsial life cycle. IMPORTANCE Rickettsia spp. are obligate intracellular bacterial pathogens that pose a growing threat to human health. Nevertheless, their strict reliance on a host cell niche has hindered investigation of the molecular mechanisms driving rickettsial infection. This study yields much-needed insight into the Rickettsia ankyrin repeat protein RARP-1, which is conserved across the genus but has not yet been functionally characterized. Earlier work had suggested that RARP-1 is secreted into the host cytoplasm. However, the results from this work demonstrate that R. parkeri RARP-1 resides in the periplasm and is important both for invasion of host cells and for growth in the host cell cytoplasm. These results reveal RARP-1 as a novel regulator of the rickettsial life cycle.
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9
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Ortiz M, Leung PM, Shelley G, Jirapanjawat T, Nauer PA, Van Goethem MW, Bay SK, Islam ZF, Jordaan K, Vikram S, Chown SL, Hogg ID, Makhalanyane TP, Grinter R, Cowan DA, Greening C. Multiple energy sources and metabolic strategies sustain microbial diversity in Antarctic desert soils. Proc Natl Acad Sci U S A 2021; 118:e2025322118. [PMID: 34732568 PMCID: PMC8609440 DOI: 10.1073/pnas.2025322118] [Citation(s) in RCA: 56] [Impact Index Per Article: 18.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/20/2021] [Indexed: 12/11/2022] Open
Abstract
Numerous diverse microorganisms reside in the cold desert soils of continental Antarctica, though we lack a holistic understanding of the metabolic processes that sustain them. Here, we profile the composition, capabilities, and activities of the microbial communities in 16 physicochemically diverse mountainous and glacial soils. We assembled 451 metagenome-assembled genomes from 18 microbial phyla and inferred through Bayesian divergence analysis that the dominant lineages present are likely native to Antarctica. In support of earlier findings, metagenomic analysis revealed that the most abundant and prevalent microorganisms are metabolically versatile aerobes that use atmospheric hydrogen to support aerobic respiration and sometimes carbon fixation. Surprisingly, however, hydrogen oxidation in this region was catalyzed primarily by a phylogenetically and structurally distinct enzyme, the group 1l [NiFe]-hydrogenase, encoded by nine bacterial phyla. Through gas chromatography, we provide evidence that both Antarctic soil communities and an axenic Bacteroidota isolate (Hymenobacter roseosalivarius) oxidize atmospheric hydrogen using this enzyme. Based on ex situ rates at environmentally representative temperatures, hydrogen oxidation is theoretically sufficient for soil communities to meet energy requirements and, through metabolic water production, sustain hydration. Diverse carbon monoxide oxidizers and abundant methanotrophs were also active in the soils. We also recovered genomes of microorganisms capable of oxidizing edaphic inorganic nitrogen, sulfur, and iron compounds and harvesting solar energy via microbial rhodopsins and conventional photosystems. Obligately symbiotic bacteria, including Patescibacteria, Chlamydiae, and predatory Bdellovibrionota, were also present. We conclude that microbial diversity in Antarctic soils reflects the coexistence of metabolically flexible mixotrophs with metabolically constrained specialists.
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Affiliation(s)
- Maximiliano Ortiz
- Centre for Microbial Ecology and Genomics, Department of Biochemistry, Genetics and Microbiology, University of Pretoria, Pretoria 0002, South Africa
| | - Pok Man Leung
- Department of Microbiology, Monash Biomedicine Discovery Institute, Clayton VIC 3800, Australia;
| | - Guy Shelley
- School of Biological Sciences, Monash University, Clayton VIC 3800, Australia
| | - Thanavit Jirapanjawat
- Department of Microbiology, Monash Biomedicine Discovery Institute, Clayton VIC 3800, Australia
| | - Philipp A Nauer
- School of Chemistry, Monash University, Clayton VIC 3800, Australia
| | - Marc W Van Goethem
- Centre for Microbial Ecology and Genomics, Department of Biochemistry, Genetics and Microbiology, University of Pretoria, Pretoria 0002, South Africa
- Environmental Genomics and Systems Biology Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720
| | - Sean K Bay
- Department of Microbiology, Monash Biomedicine Discovery Institute, Clayton VIC 3800, Australia
- School of Biological Sciences, Monash University, Clayton VIC 3800, Australia
| | - Zahra F Islam
- Department of Microbiology, Monash Biomedicine Discovery Institute, Clayton VIC 3800, Australia
- School of Biological Sciences, Monash University, Clayton VIC 3800, Australia
| | - Karen Jordaan
- Centre for Microbial Ecology and Genomics, Department of Biochemistry, Genetics and Microbiology, University of Pretoria, Pretoria 0002, South Africa
- Departamento de Genética Molecular y Microbiología, Facultad de Ciencias Biológicas, Pontificia Universidad Católica de Chile, Santiago 8331150, Chile
| | - Surendra Vikram
- Centre for Microbial Ecology and Genomics, Department of Biochemistry, Genetics and Microbiology, University of Pretoria, Pretoria 0002, South Africa
| | - Steven L Chown
- Securing Antarctica's Environmental Future, School of Biological Sciences, Monash University, Clayton VIC 3800, Australia
| | - Ian D Hogg
- Centre for Microbial Ecology and Genomics, Department of Biochemistry, Genetics and Microbiology, University of Pretoria, Pretoria 0002, South Africa
- School of Science, University of Waikato, Hamilton 3240, New Zealand
- Polar Knowledge Canada, Canadian High Arctic Research Station, Cambridge Bay NU X0B 0C0, Canada
| | - Thulani P Makhalanyane
- Centre for Microbial Ecology and Genomics, Department of Biochemistry, Genetics and Microbiology, University of Pretoria, Pretoria 0002, South Africa
| | - Rhys Grinter
- Department of Microbiology, Monash Biomedicine Discovery Institute, Clayton VIC 3800, Australia
| | - Don A Cowan
- Centre for Microbial Ecology and Genomics, Department of Biochemistry, Genetics and Microbiology, University of Pretoria, Pretoria 0002, South Africa;
| | - Chris Greening
- Department of Microbiology, Monash Biomedicine Discovery Institute, Clayton VIC 3800, Australia;
- School of Biological Sciences, Monash University, Clayton VIC 3800, Australia
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10
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Ezzedine JA, Desdevises Y, Jacquet S. Bdellovibrio and like organisms: current understanding and knowledge gaps of the smallest cellular hunters of the microbial world. Crit Rev Microbiol 2021; 48:428-449. [PMID: 34595998 DOI: 10.1080/1040841x.2021.1979464] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
Abstract
Almost sixty years ago, Bdellovibrio and like organisms (BALOs) were discovered as the first obligate bacterial predators of other bacteria known to science. Since then, they were shown to be diverse and ubiquitous in the environment, and to bear astonishing ecological, physiological, and metabolic capabilities. The last decade has seen important strides made in understanding the mechanistic basis of their life cycle, the dynamics of their interactions with prey, along with significant developments towards their use in medicine, agriculture, and industry. This review details these achievements, identify current understanding and knowledge gaps to encourage and guide future BALO research.
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Affiliation(s)
- Jade A Ezzedine
- Université Savoie Mont-Blanc, INRAE, CARRTEL, Thonon-les-Bains, France.,Laboratoire de Physiologie Cellulaire et Végétale, CNRS, CEA, INRAE, IRIG, Université Grenoble Alpes, Grenoble, France
| | - Yves Desdevises
- CNRS, Biologie Intégrative des Organismes Marins, Observatoire Océanologique, Sorbonne Université, Banyuls-sur-Mer, France
| | - Stéphan Jacquet
- Université Savoie Mont-Blanc, INRAE, CARRTEL, Thonon-les-Bains, France
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11
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Mishra S, Looger LL, Porter LL. A sequence-based method for predicting extant fold switchers that undergo α-helix ↔ β-strand transitions. Biopolymers 2021; 112:e23471. [PMID: 34498740 PMCID: PMC8545793 DOI: 10.1002/bip.23471] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2021] [Revised: 08/10/2021] [Accepted: 08/10/2021] [Indexed: 12/21/2022]
Abstract
Extant fold-switching proteins remodel their secondary structures and change their functions in response to cellular stimuli, regulating biological processes and affecting human health. Despite their biological importance, these proteins remain understudied. Predictive methods are needed to expedite the process of discovering and characterizing more of these shapeshifting proteins. Most previous approaches require a solved structure or all-atom simulations, greatly constraining their use. Here, we propose a high-throughput sequence-based method for predicting extant fold switchers that transition from α-helix in one conformation to β-strand in the other. This method leverages two previous observations: (a) α-helix ↔ β-strand prediction discrepancies from JPred4 are a robust predictor of fold switching, and (b) the fold-switching regions (FSRs) of some extant fold switchers have different secondary structure propensities when expressed by themselves (isolated FSRs) than when expressed within the context of their parent protein (contextualized FSRs). Combining these two observations, we ran JPred4 on 99-fold-switching proteins and found strong correspondence between predicted and experimentally observed α-helix ↔ β-strand discrepancies. To test the overall robustness of this finding, we randomly selected regions of proteins not expected to switch folds (single-fold proteins) and found significantly fewer predicted α-helix ↔ β-strand discrepancies. Combining these discrepancies with the overall percentage of predicted secondary structure, we developed a classifier to identify extant fold switchers (Matthews correlation coefficient of .71). Although this classifier had a high false-negative rate (7/17), its false-positive rate was very low (2/136), suggesting that it can be used to predict a subset of extant fold switchers from a multitude of available genomic sequences.
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Affiliation(s)
- Soumya Mishra
- National Library of MedicineNational Institutes of HealthBethesdaMarylandUSA
- Howard Hughes Medical Institute, Janelia Research CampusAshburnVirginiaUSA
| | - Loren L. Looger
- Howard Hughes Medical Institute, Janelia Research CampusAshburnVirginiaUSA
| | - Lauren L. Porter
- National Library of MedicineNational Institutes of HealthBethesdaMarylandUSA
- National Heart, Lung, and Blood InstituteNational Institutes of HealthBethesdaMarylandUSA
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12
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Robinson L, Liaw J, Omole Z, Xia D, van Vliet AHM, Corcionivoschi N, Hachani A, Gundogdu O. Bioinformatic Analysis of the Campylobacter jejuni Type VI Secretion System and Effector Prediction. Front Microbiol 2021; 12:694824. [PMID: 34276628 PMCID: PMC8285248 DOI: 10.3389/fmicb.2021.694824] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2021] [Accepted: 06/07/2021] [Indexed: 12/30/2022] Open
Abstract
The Type VI Secretion System (T6SS) has important roles relating to bacterial antagonism, subversion of host cells, and niche colonisation. Campylobacter jejuni is one of the leading bacterial causes of human gastroenteritis worldwide and is a commensal coloniser of birds. Although recently discovered, the T6SS biological functions and identities of its effectors are still poorly defined in C. jejuni. Here, we perform a comprehensive bioinformatic analysis of the C. jejuni T6SS by investigating the prevalence and genetic architecture of the T6SS in 513 publicly available genomes using C. jejuni 488 strain as reference. A unique and conserved T6SS cluster associated with the Campylobacter jejuni Integrated Element 3 (CJIE3) was identified in the genomes of 117 strains. Analyses of the T6SS-positive 488 strain against the T6SS-negative C. jejuni RM1221 strain and the T6SS-positive plasmid pCJDM202 carried by C. jejuni WP2-202 strain defined the “T6SS-containing CJIE3” as a pathogenicity island, thus renamed as Campylobacter jejuni Pathogenicity Island-1 (CJPI-1). Analysis of CJPI-1 revealed two canonical VgrG homologues, CJ488_0978 and CJ488_0998, harbouring distinct C-termini in a genetically variable region downstream of the T6SS operon. CJPI-1 was also found to carry a putative DinJ-YafQ Type II toxin-antitoxin (TA) module, conserved across pCJDM202 and the genomic island CJIE3, as well as several open reading frames functionally predicted to encode for nucleases, lipases, and peptidoglycan hydrolases. This comprehensive in silico study provides a framework for experimental characterisation of T6SS-related effectors and TA modules in C. jejuni.
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Affiliation(s)
- Luca Robinson
- Faculty of Infectious and Tropical Diseases, London School of Hygiene & Tropical Medicine, London, United Kingdom
| | - Janie Liaw
- Faculty of Infectious and Tropical Diseases, London School of Hygiene & Tropical Medicine, London, United Kingdom
| | - Zahra Omole
- Faculty of Infectious and Tropical Diseases, London School of Hygiene & Tropical Medicine, London, United Kingdom
| | - Dong Xia
- Comparative Biomedical Sciences, Royal Veterinary College, London, United Kingdom
| | - Arnoud H M van Vliet
- School of Veterinary Medicine, Faculty of Health and Medical Sciences, University of Surrey, Guildford, United Kingdom
| | - Nicolae Corcionivoschi
- Bacteriology Branch, Veterinary Sciences Division, Agri-Food and Biosciences Institute, Belfast, United Kingdom.,Bioengineering of Animal Science Resources, Banat University of Agricultural Sciences and Veterinary Medicine - King Michael the I of Romania, Timisoara, Romania
| | - Abderrahman Hachani
- The Peter Doherty Institute for Infection and Immunity, Department of Microbiology and Immunology, University of Melbourne, Melbourne, VIC, Australia
| | - Ozan Gundogdu
- Faculty of Infectious and Tropical Diseases, London School of Hygiene & Tropical Medicine, London, United Kingdom
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13
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Moreira D, Zivanovic Y, López-Archilla AI, Iniesto M, López-García P. Reductive evolution and unique predatory mode in the CPR bacterium Vampirococcus lugosii. Nat Commun 2021; 12:2454. [PMID: 33911080 PMCID: PMC8080830 DOI: 10.1038/s41467-021-22762-4] [Citation(s) in RCA: 49] [Impact Index Per Article: 16.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2020] [Accepted: 03/18/2021] [Indexed: 12/27/2022] Open
Abstract
The Candidate Phyla Radiation (CPR) constitutes a large group of mostly uncultured bacterial lineages with small cell sizes and limited biosynthetic capabilities. They are thought to be symbionts of other organisms, but the nature of this symbiosis has been ascertained only for cultured Saccharibacteria, which are epibiotic parasites of other bacteria. Here, we study the biology and the genome of Vampirococcus lugosii, which becomes the first described species of Vampirococcus, a genus of epibiotic bacteria morphologically identified decades ago. Vampirococcus belongs to the CPR phylum Absconditabacteria. It feeds on anoxygenic photosynthetic gammaproteobacteria, fully absorbing their cytoplasmic content. The cells divide epibiotically, forming multicellular stalks whose apical cells can reach new hosts. The genome is small (1.3 Mbp) and highly reduced in biosynthetic metabolism genes, but is enriched in genes possibly related to a fibrous cell surface likely involved in interactions with the host. Gene loss has been continuous during the evolution of Absconditabacteria, and generally most CPR bacteria, but this has been compensated by gene acquisition by horizontal gene transfer and de novo evolution. Our findings support parasitism as a widespread lifestyle of CPR bacteria, which probably contribute to the control of bacterial populations in diverse ecosystems.
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Affiliation(s)
- David Moreira
- Ecologie Systématique Evolution, CNRS, Université Paris-Saclay, AgroParisTech, Orsay, France.
| | - Yvan Zivanovic
- Institut de Biologie Intégrative de la Cellule, CNRS, Université Paris-Saclay, Orsay, France
| | | | - Miguel Iniesto
- Ecologie Systématique Evolution, CNRS, Université Paris-Saclay, AgroParisTech, Orsay, France
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14
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Lovering AL, Sockett RE. Microbe Profile: Bdellovibrio bacteriovorus: a specialized bacterial predator of bacteria. MICROBIOLOGY-SGM 2021; 167. [PMID: 33843574 PMCID: PMC8289219 DOI: 10.1099/mic.0.001043] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Bdellovibrio bacteriovorus is an environmentally-ubiquitous bacterium that uses unique adaptations to kill other bacteria. The best-characterized strain, HD100, has a multistage lifestyle, with both a free-living attack phase and an intraperiplasmic growth and division phase inside the prey cell. Advances in understanding the basic biology and regulation of predation processes are paving the way for future potential therapeutic and bioremediation applications of this unusual bacterium.
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15
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A lysozyme with altered substrate specificity facilitates prey cell exit by the periplasmic predator Bdellovibrio bacteriovorus. Nat Commun 2020; 11:4817. [PMID: 32968056 PMCID: PMC7511926 DOI: 10.1038/s41467-020-18139-8] [Citation(s) in RCA: 26] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2019] [Accepted: 08/06/2020] [Indexed: 11/16/2022] Open
Abstract
Lysozymes are among the best-characterized enzymes, acting upon the cell wall substrate peptidoglycan. Here, examining the invasive bacterial periplasmic predator Bdellovibrio bacteriovorus, we report a diversified lysozyme, DslA, which acts, unusually, upon (GlcNAc-) deacetylated peptidoglycan. B. bacteriovorus are known to deacetylate the peptidoglycan of the prey bacterium, generating an important chemical difference between prey and self walls and implying usage of a putative deacetyl-specific “exit enzyme”. DslA performs this role, and ΔDslA strains exhibit a delay in leaving from prey. The structure of DslA reveals a modified lysozyme superfamily fold, with several adaptations. Biochemical assays confirm DslA specificity for deacetylated cell wall, and usage of two glutamate residues for catalysis. Exogenous DslA, added ex vivo, is able to prematurely liberate B. bacteriovorus from prey, part-way through the predatory lifecycle. We define a mechanism for specificity that invokes steric selection, and use the resultant motif to identify wider DslA homologues. The bacterial periplasmic predator Bdellovibrio bacteriovorus deacetylates the peptidoglycan of the prey bacterium early upon invasion. Here, the authors identify and characterize a Bdellovibrio lysozyme that acts specifically on deacetylated peptidoglycan and is important for periplasmic exit.
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Caulton SG, Lovering AL. Bacterial invasion and killing by predatory Bdellovibrio primed by predator prey cell recognition and self protection. Curr Opin Microbiol 2020; 56:74-80. [DOI: 10.1016/j.mib.2020.07.002] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2020] [Revised: 07/07/2020] [Accepted: 07/12/2020] [Indexed: 01/13/2023]
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Bonfiglio G, Neroni B, Radocchia G, Marazzato M, Pantanella F, Schippa S. Insight into the Possible Use of the Predator Bdellovibrio bacteriovorus as a Probiotic. Nutrients 2020; 12:E2252. [PMID: 32731403 PMCID: PMC7468853 DOI: 10.3390/nu12082252] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2020] [Revised: 07/23/2020] [Accepted: 07/24/2020] [Indexed: 12/25/2022] Open
Abstract
The gut microbiota is a complex microbial ecosystem that coexists with the human organism in the intestinal tract. The members of this ecosystem live together in a balance between them and the host, contributing to its healthy state. Stress, aging, and antibiotic therapies are the principal factors affecting the gut microbiota composition, breaking the mutualistic relationship among microbes and resulting in the overgrowth of potential pathogens. This condition, called dysbiosis, has been linked to several chronic pathologies. In this review, we propose the use of the predator Bdellovibrio bacteriovorus as a possible probiotic to prevent or counteract dysbiotic outcomes and look at the findings of previous research.
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Bratanis E, Andersson T, Lood R, Bukowska-Faniband E. Biotechnological Potential of Bdellovibrio and Like Organisms and Their Secreted Enzymes. Front Microbiol 2020; 11:662. [PMID: 32351487 PMCID: PMC7174725 DOI: 10.3389/fmicb.2020.00662] [Citation(s) in RCA: 39] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2019] [Accepted: 03/23/2020] [Indexed: 02/01/2023] Open
Abstract
Bdellovibrio and like organisms (BALOs) are obligate predatory bacteria that selectively prey on a broad range of Gram-negative bacteria, including multidrug-resistant human pathogens. Due to their unique lifestyle, they have been long recognized as a potential therapeutic and biocontrol agent. Research on BALOs has rapidly grown over the recent decade, resulting in many publications concerning molecular details of bacterial predation as well as applications thereof in medicine and biotechnology. This review summarizes the current knowledge on biotechnological potential of obligate predatory bacteria and their secreted enzymes.
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Affiliation(s)
- Eleni Bratanis
- Division of Infection Medicine, Department of Clinical Sciences, Lund University, Lund, Sweden
| | - Tilde Andersson
- Division of Infection Medicine, Department of Clinical Sciences, Lund University, Lund, Sweden
| | - Rolf Lood
- Division of Infection Medicine, Department of Clinical Sciences, Lund University, Lund, Sweden
| | - Ewa Bukowska-Faniband
- Division of Infection Medicine, Department of Clinical Sciences, Lund University, Lund, Sweden
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19
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Laloux G. Shedding Light on the Cell Biology of the Predatory Bacterium Bdellovibrio bacteriovorus. Front Microbiol 2020; 10:3136. [PMID: 32038570 PMCID: PMC6985089 DOI: 10.3389/fmicb.2019.03136] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2019] [Accepted: 12/26/2019] [Indexed: 12/25/2022] Open
Abstract
Bdellovibrio bacteriovorus is a predatory bacterium that feeds upon and proliferates inside other Gram-negative bacteria. Upon entry into the periplasmic space of the prey envelope, B. bacteriovorus initiates an exquisite developmental program in which it digests the host resources and grows as a filament, which eventually divides in a non-binary manner, releasing a variable number of daughter cells. The progeny then escape from the prey ghost to encounter new victims and resume the predation cycle. Owing to its unique biology, B. bacteriovorus undoubtedly represents an attractive model to unravel novel mechanisms of bacterial cell cycle control and cellular organization. Yet, the molecular factors behind the sophisticated lifestyle of this micro-predator are still mysterious. In particular, the spatiotemporal dynamics of proteins that control key cellular processes such as transmission of the genetic information, cell growth and division remain largely unexplored. In this Perspective article, I highlight outstanding fundamental questions related to these aspects and arising from the original biology of this bacterium. I also discuss available insights and potential cell biology approaches based on quantitative live imaging techniques, in combination with bacterial genetics and biochemistry, to shed light on the intracellular organization of B. bacteriovorus in space and time.
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Affiliation(s)
- Géraldine Laloux
- de Duve Institute, Université catholique de Louvain, Brussels, Belgium
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20
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Tang BL, Yang J, Chen XL, Wang P, Zhao HL, Su HN, Li CY, Yu Y, Zhong S, Wang L, Lidbury I, Ding H, Wang M, McMinn A, Zhang XY, Chen Y, Zhang YZ. A predator-prey interaction between a marine Pseudoalteromonas sp. and Gram-positive bacteria. Nat Commun 2020; 11:285. [PMID: 31941905 PMCID: PMC6962226 DOI: 10.1038/s41467-019-14133-x] [Citation(s) in RCA: 41] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2019] [Accepted: 12/13/2019] [Indexed: 12/23/2022] Open
Abstract
Predator-prey interactions play important roles in the cycling of marine organic matter. Here we show that a Gram-negative bacterium isolated from marine sediments (Pseudoalteromonas sp. strain CF6-2) can kill Gram-positive bacteria of diverse peptidoglycan (PG) chemotypes by secreting the metalloprotease pseudoalterin. Secretion of the enzyme requires a Type II secretion system. Pseudoalterin binds to the glycan strands of Gram positive bacterial PG and degrades the PG peptide chains, leading to cell death. The released nutrients, including PG-derived D-amino acids, can then be utilized by strain CF6-2 for growth. Pseudoalterin synthesis is induced by PG degradation products such as glycine and glycine-rich oligopeptides. Genes encoding putative pseudoalterin-like proteins are found in many other marine bacteria. This study reveals a new microbial interaction in the ocean. Predator-prey interactions play important roles in the cycling of marine organic matter. Here the authors show that a Gram-negative bacterium isolated from marine sediments can kill and feed on Gram-positive bacteria by secreting a peptidoglycan-degrading enzyme.
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Affiliation(s)
- Bai-Lu Tang
- State Key Laboratory of Microbial Technology, Marine Biotechnology Research Center, Shandong University, Qingdao, 266237, China
| | - Jie Yang
- State Key Laboratory of Microbial Technology, Marine Biotechnology Research Center, Shandong University, Qingdao, 266237, China
| | - Xiu-Lan Chen
- State Key Laboratory of Microbial Technology, Marine Biotechnology Research Center, Shandong University, Qingdao, 266237, China
| | - Peng Wang
- State Key Laboratory of Microbial Technology, Marine Biotechnology Research Center, Shandong University, Qingdao, 266237, China.,College of Marine Life Sciences, Institute for Advanced Ocean Study, Ocean University of China, Qingdao, 266003, China
| | - Hui-Lin Zhao
- State Key Laboratory of Microbial Technology, Marine Biotechnology Research Center, Shandong University, Qingdao, 266237, China
| | - Hai-Nan Su
- State Key Laboratory of Microbial Technology, Marine Biotechnology Research Center, Shandong University, Qingdao, 266237, China
| | - Chun-Yang Li
- College of Marine Life Sciences, Institute for Advanced Ocean Study, Ocean University of China, Qingdao, 266003, China.,Laboratory for Marine Biology and Biotechnology, Pilot National Laboratory for Marine Science and Technology (Qingdao), Qingdao, 266373, China
| | - Yang Yu
- State Key Laboratory of Microbial Technology, Marine Biotechnology Research Center, Shandong University, Qingdao, 266237, China
| | - Shuai Zhong
- State Key Laboratory of Microbial Technology, Marine Biotechnology Research Center, Shandong University, Qingdao, 266237, China
| | - Lei Wang
- State Key Laboratory of Microbial Technology, Marine Biotechnology Research Center, Shandong University, Qingdao, 266237, China
| | - Ian Lidbury
- School of Life Sciences, University of Warwick, Coventry, UK
| | - Haitao Ding
- SOA Key Laboratory for Polar Science, Polar Research Institute of China, Shanghai, 200136, China
| | - Min Wang
- College of Marine Life Sciences, Institute for Advanced Ocean Study, Ocean University of China, Qingdao, 266003, China
| | - Andrew McMinn
- College of Marine Life Sciences, Institute for Advanced Ocean Study, Ocean University of China, Qingdao, 266003, China.,Institute for Marine and Antarctic Studies, University of Tasmania, Hobart, TAS, Australia
| | - Xi-Ying Zhang
- State Key Laboratory of Microbial Technology, Marine Biotechnology Research Center, Shandong University, Qingdao, 266237, China
| | - Yin Chen
- College of Marine Life Sciences, Institute for Advanced Ocean Study, Ocean University of China, Qingdao, 266003, China.,School of Life Sciences, University of Warwick, Coventry, UK
| | - Yu-Zhong Zhang
- State Key Laboratory of Microbial Technology, Marine Biotechnology Research Center, Shandong University, Qingdao, 266237, China. .,College of Marine Life Sciences, Institute for Advanced Ocean Study, Ocean University of China, Qingdao, 266003, China. .,Laboratory for Marine Biology and Biotechnology, Pilot National Laboratory for Marine Science and Technology (Qingdao), Qingdao, 266373, China.
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21
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Jahn MT, Arkhipova K, Markert SM, Stigloher C, Lachnit T, Pita L, Kupczok A, Ribes M, Stengel ST, Rosenstiel P, Dutilh BE, Hentschel U. A Phage Protein Aids Bacterial Symbionts in Eukaryote Immune Evasion. Cell Host Microbe 2019; 26:542-550.e5. [PMID: 31561965 DOI: 10.1016/j.chom.2019.08.019] [Citation(s) in RCA: 71] [Impact Index Per Article: 14.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2019] [Revised: 07/22/2019] [Accepted: 08/30/2019] [Indexed: 11/27/2022]
Abstract
Phages are increasingly recognized as important members of host-associated microbiomes, with a vast genomic diversity. The new frontier is to understand how phages may affect higher order processes, such as in the context of host-microbe interactions. Here, we use marine sponges as a model to investigate the interplay between phages, bacterial symbionts, and eukaryotic hosts. Using viral metagenomics, we find that sponges, although massively filtering seawater, harbor species-specific and even individually unique viral signatures that are taxonomically distinct from other environments. We further discover a symbiont phage-encoded ankyrin-domain-containing protein, which is widely spread in phages of many host-associated contexts including human. We confirm in macrophage infection assays that the ankyrin protein (ANKp) modulates the eukaryotic host immune response against bacteria. We predict that the role of ANKp in nature is to facilitate coexistence in the tripartite interplay between phages, symbionts, and sponges and possibly many other host-microbe associations.
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Affiliation(s)
- Martin T Jahn
- GEOMAR Helmholtz Centre for Ocean Research Kiel, Marine Symbioses, 24105 Kiel, Germany.
| | - Ksenia Arkhipova
- Theoretical Biology and Bioinformatics, Utrecht University, 3584 Utrecht, the Netherlands
| | - Sebastian M Markert
- Imaging Core Facility, Biocenter, University of Würzburg, 97074 Würzburg, Germany
| | - Christian Stigloher
- Imaging Core Facility, Biocenter, University of Würzburg, 97074 Würzburg, Germany
| | - Tim Lachnit
- Christian-Albrechts-University of Kiel, 24105 Kiel, Germany
| | - Lucia Pita
- GEOMAR Helmholtz Centre for Ocean Research Kiel, Marine Symbioses, 24105 Kiel, Germany
| | - Anne Kupczok
- Christian-Albrechts-University of Kiel, 24105 Kiel, Germany
| | - Marta Ribes
- Institut de Ciències del Mar-CSIC, 08003 Barcelona, Spain
| | - Stephanie T Stengel
- Institute of Clinical Molecular Biology, University Hospital Schleswig-Holstein, 24105 Kiel, Germany
| | - Philip Rosenstiel
- Christian-Albrechts-University of Kiel, 24105 Kiel, Germany; Institute of Clinical Molecular Biology, University Hospital Schleswig-Holstein, 24105 Kiel, Germany
| | - Bas E Dutilh
- Theoretical Biology and Bioinformatics, Utrecht University, 3584 Utrecht, the Netherlands
| | - Ute Hentschel
- GEOMAR Helmholtz Centre for Ocean Research Kiel, Marine Symbioses, 24105 Kiel, Germany; Christian-Albrechts-University of Kiel, 24105 Kiel, Germany.
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22
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Dynamics of Chromosome Replication and Its Relationship to Predatory Attack Lifestyles in Bdellovibrio bacteriovorus. Appl Environ Microbiol 2019; 85:AEM.00730-19. [PMID: 31076424 PMCID: PMC6606864 DOI: 10.1128/aem.00730-19] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2019] [Accepted: 05/04/2019] [Indexed: 12/20/2022] Open
Abstract
Bdellovibrio bacteriovorus is a small Gram-negative, obligate predatory bacterium that is largely found in wet, aerobic environments (e.g., soil). This bacterium attacks and invades other Gram-negative bacteria, including animal and plant pathogens. The intriguing life cycle of B. bacteriovorus consists of two phases: a free-living nonreplicative attack phase, in which the predatory bacterium searches for its prey, and a reproductive phase, in which B. bacteriovorus degrades a host's macromolecules and reuses them for its own growth and chromosome replication. Although the cell biology of this predatory bacterium has gained considerable interest in recent years, we know almost nothing about the dynamics of its chromosome replication. Here, we performed a real-time investigation into the subcellular localization of the replisome(s) in single cells of B. bacteriovorus Our results show that in B. bacteriovorus, chromosome replication takes place only during the reproductive phase and exhibits a novel spatiotemporal arrangement of replisomes. The replication process starts at the invasive pole of the predatory bacterium inside the prey cell and proceeds until several copies of the chromosome have been completely synthesized. Chromosome replication is not coincident with the predator cell division, and it terminates shortly before synchronous predator filament septation occurs. In addition, we demonstrate that if this B. bacteriovorus life cycle fails in some cells of Escherichia coli, they can instead use second prey cells to complete their life cycle.IMPORTANCE New strategies are needed to combat multidrug-resistant bacterial infections. Application of the predatory bacterium Bdellovibrio bacteriovorus, which kills other bacteria, including pathogens, is considered promising for combating bacterial infections. The B. bacteriovorus life cycle consists of two phases, a free-living, invasive attack phase and an intracellular reproductive phase, in which this predatory bacterium degrades the host's macromolecules and reuses them for its own growth. To understand the use of B. bacteriovorus as a "living antibiotic," it is first necessary to dissect its life cycle, including chromosome replication. Here, we present a real-time investigation into subcellular localization of chromosome replication in a single cell of B. bacteriovorus This process initiates at the invasion pole of B. bacteriovorus and proceeds until several copies of the chromosome have been completely synthesized. Interestingly, we demonstrate that some cells of B. bacteriovorus require two prey cells sequentially to complete their life cycle.
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23
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Deeg CM, Zimmer MM, George EE, Husnik F, Keeling PJ, Suttle CA. Chromulinavorax destructans, a pathogen of microzooplankton that provides a window into the enigmatic candidate phylum Dependentiae. PLoS Pathog 2019; 15:e1007801. [PMID: 31150530 PMCID: PMC6561590 DOI: 10.1371/journal.ppat.1007801] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2019] [Revised: 06/12/2019] [Accepted: 04/30/2019] [Indexed: 11/25/2022] Open
Abstract
Members of the major candidate phylum Dependentiae (a.k.a. TM6) are widespread across diverse environments from showerheads to peat bogs; yet, with the exception of two isolates infecting amoebae, they are only known from metagenomic data. The limited knowledge of their biology indicates that they have a long evolutionary history of parasitism. Here, we present Chromulinavorax destructans (Strain SeV1) the first isolate of this phylum to infect a representative from a widespread and ecologically significant group of heterotrophic flagellates, the microzooplankter Spumella elongata (Strain CCAP 955/1). Chromulinavorax destructans has a reduced 1.2 Mb genome that is so specialized for infection that it shows no evidence of complete metabolic pathways, but encodes an extensive transporter system for importing nutrients and energy in the form of ATP from the host. Its replication causes extensive reorganization and expansion of the mitochondrion, effectively surrounding the pathogen, consistent with its dependency on the host for energy. Nearly half (44%) of the inferred proteins contain signal sequences for secretion, including many without recognizable similarity to proteins of known function, as well as 98 copies of proteins with an ankyrin-repeat domain; ankyrin-repeats are known effectors of host modulation, suggesting the presence of an extensive host-manipulation apparatus. These observations help to cement members of this phylum as widespread and diverse parasites infecting a broad range of eukaryotic microbes. Little is known about the biology of bacteria in the candidate phylum Dependentiae, despite being widespread in nature. Here, we describe a novel isolate of this phylum, Chromulinavorax destructans, which infects an abundant aquatic predatory protist, Spumella elongata. Chromulinavorax destructans is an obligate intracellular parasite, forgoes binary fission and replicates surrounded by the host mitochondrion. The genome of C. destructans encodes no detectable complete metabolic pathways and instead contains extensive transporter systems to import metabolites and even energy in the form of ATP from the host. We also found a surprising number of genes in the C. destructans genome encoding putative host modifying proteins that might be responsible for the extensive host reorganization. Phylogenetic analysis showed that C. destructans is distantly related to intracellular pathogens and symbionts of unrelated amoebae. Hence, Chromulinavorax destructans provides new insights into the biology of a widespread but largely unknown phylum of bacteria. These results imply that members of the Dependentiae are pathogens of diverse aquatic protists and are therefore likely important players in aquatic ecosystems.
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Affiliation(s)
- Christoph M. Deeg
- Department of Microbiology and Immunology, University of British Columbia, Vancouver, Canada
| | - Matthias M. Zimmer
- Department of Earth, Ocean and Atmospheric Sciences, University of British Columbia, Vancouver, Canada
| | - Emma E. George
- Department of Botany, University of British Columbia, Vancouver, Canada
| | - Filip Husnik
- Department of Botany, University of British Columbia, Vancouver, Canada
| | | | - Curtis A. Suttle
- Department of Microbiology and Immunology, University of British Columbia, Vancouver, Canada
- Department of Earth, Ocean and Atmospheric Sciences, University of British Columbia, Vancouver, Canada
- Department of Botany, University of British Columbia, Vancouver, Canada
- Institute for the Oceans and Fisheries, University of British Columbia, Vancouver, Canada
- * E-mail:
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24
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Whole-Genome Sequencing and Comparative Genome Analysis Provided Insight into the Predatory Features and Genetic Diversity of Two Bdellovibrio Species Isolated from Soil. Int J Genomics 2018; 2018:9402073. [PMID: 29850478 PMCID: PMC5941755 DOI: 10.1155/2018/9402073] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2017] [Revised: 01/24/2018] [Accepted: 02/19/2018] [Indexed: 01/07/2023] Open
Abstract
Bdellovibrio spp. are predatory bacteria with great potential as antimicrobial agents. Studies have shown that members of the genus Bdellovibrio exhibit peculiar characteristics that influence their ecological adaptations. In this study, whole genomes of two different Bdellovibrio spp. designated SKB1291214 and SSB218315 isolated from soil were sequenced. The core genes shared by all the Bdellovibrio spp. considered for the pangenome analysis including the epibiotic B. exovorus were 795. The number of unique genes identified in Bdellovibrio spp. SKB1291214, SSB218315, W, and B. exovorus JJS was 1343, 113, 857, and 1572, respectively. These unique genes encode hydrolytic, chemotaxis, and transporter proteins which might be useful for predation in the Bdellovibrio strains. Furthermore, the two Bdellovibrio strains exhibited differences based on the % GC content, amino acid identity, and 16S rRNA gene sequence. The 16S rRNA gene sequence of Bdellovibrio sp. SKB1291214 shared 99% identity with that of an uncultured Bdellovibrio sp. clone 12L 106 (a pairwise distance of 0.008) and 95-97% identity (a pairwise distance of 0.043) with that of other culturable terrestrial Bdellovibrio spp., including strain SSB218315. In Bdellovibrio sp. SKB1291214, 174 bp sequence was inserted at the host interaction (hit) locus region usually attributed to prey attachment, invasion, and development of host independent Bdellovibrio phenotypes. Also, a gene equivalent to Bd0108 in B. bacteriovorus HD100 was not conserved in Bdellovibrio sp. SKB1291214. The results of this study provided information on the genetic characteristics and diversity of the genus Bdellovibrio that can contribute to their successful applications as a biocontrol agent.
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Negus D, Moore C, Baker M, Raghunathan D, Tyson J, Sockett RE. Predator Versus Pathogen: How Does Predatory Bdellovibrio bacteriovorus Interface with the Challenges of Killing Gram-Negative Pathogens in a Host Setting? Annu Rev Microbiol 2018; 71:441-457. [PMID: 28886689 DOI: 10.1146/annurev-micro-090816-093618] [Citation(s) in RCA: 51] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Bdellovibrio bacteriovorus is a small deltaproteobacterial predator that has evolved to invade, reseal, kill, and digest other gram-negative bacteria in soils and water environments. It has a broad host range and kills many antibiotic-resistant, clinical pathogens in vitro, a potentially useful capability if it could be translated to a clinical setting. We review relevant mechanisms of B. bacteriovorus predation and the physiological properties that would influence its survival in a mammalian host. Bacterial pathogens increasingly display conventional antibiotic resistance by expressing and varying surface and soluble biomolecules. Predators coevolved alongside prey bacteria and so encode diverse predatory enzymes that are hard for pathogens to resist by simple mutation. Predators do not replicate outside pathogens and thus express few transport proteins and thus few surface epitopes for host immune recognition. We explain these features, relating them to the potential of predatory bacteria as cellular medicines.
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Affiliation(s)
- David Negus
- School of Life Science, University of Nottingham, University Park, Nottingham NG7 2UH, United Kingdom; , , , , ,
| | - Chris Moore
- School of Life Science, University of Nottingham, University Park, Nottingham NG7 2UH, United Kingdom; , , , , ,
| | - Michelle Baker
- School of Life Science, University of Nottingham, University Park, Nottingham NG7 2UH, United Kingdom; , , , , , .,School of Computer Science, University of Nottingham, University Park, Nottingham NG7 2UH, United Kingdom
| | - Dhaarini Raghunathan
- School of Life Science, University of Nottingham, University Park, Nottingham NG7 2UH, United Kingdom; , , , , ,
| | - Jess Tyson
- School of Life Science, University of Nottingham, University Park, Nottingham NG7 2UH, United Kingdom; , , , , ,
| | - R Elizabeth Sockett
- School of Life Science, University of Nottingham, University Park, Nottingham NG7 2UH, United Kingdom; , , , , ,
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26
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Heidari Tajabadi F, Medrano-Soto A, Ahmadzadeh M, Salehi Jouzani G, Saier MH. Comparative Analyses of Transport Proteins Encoded within the Genomes of Bdellovibrio bacteriovorus HD100 and Bdellovibrio exovorus JSS. J Mol Microbiol Biotechnol 2017; 27:332-349. [PMID: 29212086 DOI: 10.1159/000484563] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2017] [Accepted: 10/17/2017] [Indexed: 12/21/2022] Open
Abstract
Bdellovibrio, δ-proteobacteria, including B. bacteriovorus (Bba) and B. exovorus (Bex), are obligate predators of other Gram-negative bacteria. While Bba grows in the periplasm of the prey cell, Bex grows externally. We have analyzed and compared the transport proteins of these 2 organisms based on the current contents of the Transporter Classification Database (TCDB; www.tcdb.org). Bba has 103 transporters more than Bex, 50% more secondary carriers, and 3 times as many MFS carriers. Bba has far more metabolite transporters than Bex as expected from its larger genome, but there are 2 times more carbohydrate uptake and drug efflux systems, and 3 times more lipid transporters. Bba also has polyamine and carboxylate transporters lacking in Bex. Bba has more than twice as many members of the Mot-Exb family of energizers, but both may have energizers for gliding motility. They use entirely different types of systems for iron acquisition. Both contain unexpectedly large numbers of pseudogenes and incomplete systems, suggesting that they are undergoing genome size reduction. Interestingly, all 5 outer-membrane receptors in Bba are lacking in Bex. The 2 organisms have similar numbers and types of peptide and amino acid uptake systems as well as protein and carbohydrate secretion systems. The differences observed correlate with and may account, in part, for the different lifestyles of these 2 bacterial predators.
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27
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Dwidar M, Yokobayashi Y. Controlling Bdellovibrio bacteriovorus Gene Expression and Predation Using Synthetic Riboswitches. ACS Synth Biol 2017; 6:2035-2041. [PMID: 28812884 DOI: 10.1021/acssynbio.7b00171] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Bdellovibrio bacteriovorus is a predatory bacterium that feeds on Gram-negative bacteria including a wide range of pathogens and thus has potential applications as a biocontrol agent. Owing to its unique life cycle, however, there are limited tools that enable genetic manipulation of B. bacteriovorus. This work describes our first steps toward engineering the predatory bacterium for practical applications by developing basic genetic parts to control gene expression. Specifically, we evaluated four robust promoters that are active during the attack phase of B. bacteriovorus. Subsequently, we tested several synthetic riboswitches that have been reported to function in Escherichia coli, and identified theophylline-activated riboswitches that function in B. bacteriovorus. Finally, we inserted the riboswitch into the bacterial chromosome to regulate expression of the flagellar sigma factor fliA, which was previously predicted to be essential for predation, and observed that the engineered strain shows a faster predation kinetics in the presence of theophylline.
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Affiliation(s)
- Mohammed Dwidar
- Nucleic Acid Chemistry and
Engineering Unit, Okinawa Institute of Science and Technology Graduate University, Onna, Okinawa 904 0495, Japan
| | - Yohei Yokobayashi
- Nucleic Acid Chemistry and
Engineering Unit, Okinawa Institute of Science and Technology Graduate University, Onna, Okinawa 904 0495, Japan
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28
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Fluorescent D-amino-acids reveal bi-cellular cell wall modifications important for Bdellovibrio bacteriovorus predation. Nat Microbiol 2017; 2:1648-1657. [PMID: 28974693 PMCID: PMC5705579 DOI: 10.1038/s41564-017-0029-y] [Citation(s) in RCA: 77] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2016] [Accepted: 08/11/2017] [Indexed: 01/05/2023]
Abstract
Modification of essential bacterial peptidoglycan (PG) containing cell
walls can lead to antibiotic resistance, for example β-lactam resistance
by L,D-transpeptidase activities. Predatory Bdellovibrio
bacteriovorus are naturally antibacterial and combat infections by
traversing, modifying and finally destroying walls of Gram-negative prey
bacteria, modifying their own PG as they grow inside prey. Historically, these
multi-enzymatic processes on two similar PG walls have proved challenging to
elucidate. Here, with a PG labelling approach utilizing timed pulses of multiple
fluorescent D-amino acids (FDAAs), we illuminate dynamic changes that predator
and prey walls go through during the different phases of bacteria:bacteria
invasion. We show formation of a reinforced circular port-hole in the prey wall;
L,D-transpeptidaseBd mediated D-amino acid modifications
strengthening prey PG during Bdellovibrio invasion and a zonal
mode of predator-elongation. This process is followed by unconventional,
multi-point and synchronous septation of the intracellular
Bdellovibrio, accommodating odd- and even-numbered progeny
formation by non-binary division.
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29
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Baker M, Negus D, Raghunathan D, Radford P, Moore C, Clark G, Diggle M, Tyson J, Twycross J, Sockett RE. Measuring and modelling the response of Klebsiella pneumoniae KPC prey to Bdellovibrio bacteriovorus predation, in human serum and defined buffer. Sci Rep 2017; 7:8329. [PMID: 28827526 PMCID: PMC5567095 DOI: 10.1038/s41598-017-08060-4] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2017] [Accepted: 07/04/2017] [Indexed: 01/26/2023] Open
Abstract
In worldwide conditions of increasingly antibiotic-resistant hospital infections, it is important to research alternative therapies. Bdellovibrio bacteriovorus bacteria naturally prey on Gram-negative pathogens, including antibiotic-resistant strains and so B. bacteriovorus have been proposed as "living antibiotics" to combat antimicrobially-resistant pathogens. Predator-prey interactions are complex and can be altered by environmental components. To be effective B. bacteriovorus predation needs to work in human body fluids such as serum where predation dynamics may differ to that studied in laboratory media. Here we combine mathematical modelling and lab experimentation to investigate the predation of an important carbapenem-resistant human pathogen, Klebsiella pneumoniae, by B. bacteriovorus in human serum versus buffer. We show experimentally that B. bacteriovorus is able to reduce prey numbers in each environment, on different timescales. Our mathematical model captures the underlying dynamics of the experimentation, including an initial predation-delay at the predator-prey-serum interface. Our research shows differences between predation in buffer and serum and highlights both the potential and limitations of B. bacteriovorus acting therapeutically against K. pneumoniae in serum, informing future research into the medicinal behaviours and dosing of this living antibacterial.
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Affiliation(s)
- Michelle Baker
- School of Life Sciences, University of Nottingham, Medical School, Queen's Medical Centre, Nottingham, NG7 2UH, UK
- School of Computer Science, Jubilee Campus, University of Nottingham, Wollaton Road, Nottingham, NG8 1BB, UK
| | - David Negus
- School of Life Sciences, University of Nottingham, Medical School, Queen's Medical Centre, Nottingham, NG7 2UH, UK
| | - Dhaarini Raghunathan
- School of Life Sciences, University of Nottingham, Medical School, Queen's Medical Centre, Nottingham, NG7 2UH, UK
| | - Paul Radford
- School of Life Sciences, University of Nottingham, Medical School, Queen's Medical Centre, Nottingham, NG7 2UH, UK
| | - Chris Moore
- School of Life Sciences, University of Nottingham, Medical School, Queen's Medical Centre, Nottingham, NG7 2UH, UK
| | - Gemma Clark
- Empath Pathology Services Reception Floor A, West Block, Queens Medical Centre, Nottingham University Hospitals NHS Trust, Nottingham, NG7 2UH, UK
| | - Mathew Diggle
- Empath Pathology Services Reception Floor A, West Block, Queens Medical Centre, Nottingham University Hospitals NHS Trust, Nottingham, NG7 2UH, UK
| | - Jess Tyson
- School of Life Sciences, University of Nottingham, Medical School, Queen's Medical Centre, Nottingham, NG7 2UH, UK
| | - Jamie Twycross
- School of Computer Science, Jubilee Campus, University of Nottingham, Wollaton Road, Nottingham, NG8 1BB, UK
| | - R Elizabeth Sockett
- School of Life Sciences, University of Nottingham, Medical School, Queen's Medical Centre, Nottingham, NG7 2UH, UK.
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30
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Jashnsaz H, Al Juboori M, Weistuch C, Miller N, Nguyen T, Meyerhoff V, McCoy B, Perkins S, Wallgren R, Ray BD, Tsekouras K, Anderson GG, Pressé S. Hydrodynamic Hunters. Biophys J 2017; 112:1282-1289. [PMID: 28355554 PMCID: PMC5376100 DOI: 10.1016/j.bpj.2017.02.011] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2016] [Revised: 02/06/2017] [Accepted: 02/07/2017] [Indexed: 11/30/2022] Open
Abstract
The Gram-negative Bdellovibrio bacteriovorus (BV) is a model bacterial predator that hunts other bacteria and may serve as a living antibiotic. Despite over 50 years since its discovery, it is suggested that BV probably collides into its prey at random. It remains unclear to what degree, if any, BV uses chemical cues to target its prey. The targeted search problem by the predator for its prey in three dimensions is a difficult problem: it requires the predator to sensitively detect prey and forecast its mobile prey’s future position on the basis of previously detected signal. Here instead we find that rather than chemically detecting prey, hydrodynamics forces BV into regions high in prey density, thereby improving its odds of a chance collision with prey and ultimately reducing BV’s search space for prey. We do so by showing that BV’s dynamics are strongly influenced by self-generated hydrodynamic flow fields forcing BV onto surfaces and, for large enough defects on surfaces, forcing BV in orbital motion around these defects. Key experimental controls and calculations recapitulate the hydrodynamic origin of these behaviors. While BV’s prey (Escherichia coli) are too small to trap BV in hydrodynamic orbit, the prey are also susceptible to their own hydrodynamic fields, substantially confining them to surfaces and defects where mobile predator and prey density is now dramatically enhanced. Colocalization, driven by hydrodynamics, ultimately reduces BV’s search space for prey from three to two dimensions (on surfaces) even down to a single dimension (around defects). We conclude that BV’s search for individual prey remains random, as suggested in the literature, but confined, however—by generic hydrodynamic forces—to reduced dimensionality.
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Affiliation(s)
- Hossein Jashnsaz
- Department of Physics, Indiana University - Purdue University Indianapolis (IUPUI), Indianapolis, Indiana
| | - Mohammed Al Juboori
- Biomedical Engineering, Indiana University - Purdue University Indianapolis (IUPUI), Indianapolis, Indiana
| | - Corey Weistuch
- Department of Applied Mathematics and Statistics, Stony Brook University, Stony Brook, New York; Department of Biochemistry and Cell Biology, Stony Brook University, Stony Brook, New York
| | - Nicholas Miller
- Biomedical Engineering, Indiana University - Purdue University Indianapolis (IUPUI), Indianapolis, Indiana
| | - Tyler Nguyen
- Stark Neurosciences Research Institute, Indiana University School of Medicine (ISUM), Indianapolis, Indiana
| | - Viktoria Meyerhoff
- Mechanical Engineering, Indiana University - Purdue University Indianapolis (IUPUI), Indianapolis, Indiana
| | - Bryan McCoy
- Department of Chemistry and Chemical Biology, Indiana University - Purdue University Indianapolis (IUPUI), Indianapolis, Indiana
| | - Stephanie Perkins
- Department of Biology, Indiana University - Purdue University Indianapolis (IUPUI), Indianapolis, Indiana
| | - Ross Wallgren
- Department of Mathematical Sciences, Indiana University - Purdue University Indianapolis (IUPUI), Indianapolis, Indiana
| | - Bruce D Ray
- Department of Physics, Indiana University - Purdue University Indianapolis (IUPUI), Indianapolis, Indiana
| | - Konstantinos Tsekouras
- Department of Physics, Indiana University - Purdue University Indianapolis (IUPUI), Indianapolis, Indiana
| | - Gregory G Anderson
- Department of Biology, Indiana University - Purdue University Indianapolis (IUPUI), Indianapolis, Indiana.
| | - Steve Pressé
- Department of Physics, Indiana University - Purdue University Indianapolis (IUPUI), Indianapolis, Indiana; Department of Chemistry and Chemical Biology, Indiana University - Purdue University Indianapolis (IUPUI), Indianapolis, Indiana; Cellular and Integrative Physiology Department, Indiana University School of Medicine (IUSM), Indianapolis, Indiana.
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31
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Jurkevitch É, Jacquet S. [Bdellovibrio and like organisms: outstanding predators!]. Med Sci (Paris) 2017; 33:519-527. [PMID: 28612728 DOI: 10.1051/medsci/20173305016] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Obligate predatory bacteria, i.e. bacteria requiring a Gram negative prey cell in order to complete their cell cycle, belong to the polyphyletic group referred to as the Bdellovibrio And Like Organisms (BALO). Predatory interactions between bacteria are complex, yet their dynamics and impact on bacterial communities in the environment are becoming better understood. BALO have unique life cycles: they grow epibiotically with the predator remaining attached to the prey's envelope, dividing in a binary manner or periplasmically, i.e. by penetrating the prey's periplasm to generate a number of progeny cells. The periplasmic life cycle includes unique gene and protein patterns and unique signaling features. These ecological and cellular features, along with applications of the BALO in the medical, agricultural and environmental fields are surveyed.
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Affiliation(s)
- Édouard Jurkevitch
- Faculté d'Agriculture, de l'Alimentation et de l'Environnement, Université Hébraïque de Jérusalem, Rehovot, Israël
| | - Stéphan Jacquet
- INRA, UMR CARRTEL, 75, avenue de Corzent, 74200 Thonon-les-Bains, France
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32
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Lambert C, Lerner TR, Bui NK, Somers H, Aizawa SI, Liddell S, Clark A, Vollmer W, Lovering AL, Sockett RE. Interrupting peptidoglycan deacetylation during Bdellovibrio predator-prey interaction prevents ultimate destruction of prey wall, liberating bacterial-ghosts. Sci Rep 2016; 6:26010. [PMID: 27211869 PMCID: PMC4876506 DOI: 10.1038/srep26010] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2016] [Accepted: 04/22/2016] [Indexed: 11/25/2022] Open
Abstract
The peptidoglycan wall, located in the periplasm between the inner and outer membranes of the cell envelope in Gram-negative bacteria, maintains cell shape and endows osmotic robustness. Predatory Bdellovibrio bacteria invade the periplasm of other bacterial prey cells, usually crossing the peptidoglycan layer, forming transient structures called bdelloplasts within which the predators replicate. Prey peptidoglycan remains intact for several hours, but is modified and then degraded by escaping predators. Here we show predation is altered by deleting two Bdellovibrio N-acetylglucosamine (GlcNAc) deacetylases, one of which we show to have a unique two domain structure with a novel regulatory”plug”. Deleting the deacetylases limits peptidoglycan degradation and rounded prey cell “ghosts” persist after mutant-predator exit. Mutant predators can replicate unusually in the periplasmic region between the peptidoglycan wall and the outer membrane rather than between wall and inner-membrane, yet still obtain nutrients from the prey cytoplasm. Deleting two further genes encoding DacB/PBP4 family proteins, known to decrosslink and round prey peptidoglycan, results in a quadruple mutant Bdellovibrio which leaves prey-shaped ghosts upon predation. The resultant bacterial ghosts contain cytoplasmic membrane within bacteria-shaped peptidoglycan surrounded by outer membrane material which could have promise as “bacterial skeletons” for housing artificial chromosomes.
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Affiliation(s)
- Carey Lambert
- Centre for Genetics and Genomics, School of Life Sciences, University of Nottingham, Medical School, Queen's Medical Centre, Nottingham, NG7 2UH, UK
| | - Thomas R Lerner
- The Francis Crick Institute, Mill Hill Laboratory, The Ridgeway, Mill Hill, London, NW7 1AA, UK
| | - Nhat Khai Bui
- The Centre for Bacterial Cell Biology, Baddiley Clark Building, Medical School, Newcastle University, Richardson Road, Newcastle upon Tyne, NE2 4AX, UK
| | - Hannah Somers
- Centre for Genetics and Genomics, School of Life Sciences, University of Nottingham, Medical School, Queen's Medical Centre, Nottingham, NG7 2UH, UK
| | - Shin-Ichi Aizawa
- Department of Life Sciences, Prefectural University of Hiroshima, Shobara, Hiroshima, 727-0023, Japan
| | - Susan Liddell
- School of Biosciences, University of Nottingham, Sutton Bonington, Leicestershire, LE12 5RD, UK
| | - Ana Clark
- Centre for Genetics and Genomics, School of Life Sciences, University of Nottingham, Medical School, Queen's Medical Centre, Nottingham, NG7 2UH, UK
| | - Waldemar Vollmer
- The Centre for Bacterial Cell Biology, Baddiley Clark Building, Medical School, Newcastle University, Richardson Road, Newcastle upon Tyne, NE2 4AX, UK
| | - Andrew L Lovering
- Institute for Microbiology and Infection, School of Biosciences, University of Birmingham, Birmingham, B15 2TT, UK
| | - R Elizabeth Sockett
- Centre for Genetics and Genomics, School of Life Sciences, University of Nottingham, Medical School, Queen's Medical Centre, Nottingham, NG7 2UH, UK
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