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Black ME, Fei C, Alert R, Wingreen NS, Shaevitz JW. Capillary interactions drive the self-organization of bacterial colonies. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.05.28.596252. [PMID: 38853967 PMCID: PMC11160631 DOI: 10.1101/2024.05.28.596252] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2024]
Abstract
Many bacteria inhabit thin layers of water on solid surfaces both naturally in soils or on hosts or textiles and in the lab on agar hydrogels. In these environments, cells experience capillary forces, yet an understanding of how these forces shape bacterial collective behaviors remains elusive. Here, we show that the water menisci formed around bacteria lead to capillary attraction between cells while still allowing them to slide past one another. We develop an experimental apparatus that allows us to control bacterial collective behaviors by varying the strength and range of capillary forces. Combining 3D imaging and cell tracking with agent-based modeling, we demonstrate that capillary attraction organizes rod-shaped bacteria into densely packed, nematic groups, and profoundly influences their collective dynamics and morphologies. Our results suggest that capillary forces may be a ubiquitous physical ingredient in shaping microbial communities in partially hydrated environments.
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Thunes NC, Evenhuis JP, Lipscomb RS, Pérez-Pascual D, Stevick RJ, Birkett C, Ghigo JM, McBride MJ. Gliding motility proteins GldJ and SprB contribute to Flavobacterium columnare virulence. J Bacteriol 2024; 206:e0006824. [PMID: 38517170 PMCID: PMC11025331 DOI: 10.1128/jb.00068-24] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2024] [Accepted: 03/01/2024] [Indexed: 03/23/2024] Open
Abstract
Flavobacterium columnare causes columnaris disease in fish. Columnaris disease is incompletely understood, and adequate control measures are lacking. The type IX secretion system (T9SS) is required for F. columnare gliding motility and virulence. The T9SS and gliding motility machineries share some, but not all, components. GldN (required for gliding and for secretion) and PorV (involved in secretion but not required for gliding) are both needed for virulence, implicating T9SS-mediated secretion in virulence. The role of motility in virulence is uncertain. We constructed and analyzed sprB, sprF, and gldJ mutants that were defective for motility but that maintained T9SS function to understand the role of motility in virulence. Wild-type cells moved rapidly and formed spreading colonies. In contrast, sprB and sprF deletion mutants were partially defective in gliding and formed nonspreading colonies. Both mutants exhibited reduced virulence in rainbow trout fry. A gldJ deletion mutant was nonmotile, secretion deficient, and avirulent in rainbow trout fry. To separate the roles of GldJ in secretion and in motility, we generated gldJ truncation mutants that produce nearly full-length GldJ. Mutant gldJ563, which produces GldJ truncated at amino acid 563, was defective for gliding but was competent for secretion as measured by extracellular proteolytic activity. This mutant displayed reduced virulence in rainbow trout fry, suggesting that motility contributes to virulence. Fish that survived exposure to the sprB deletion mutant or the gldJ563 mutant exhibited partial resistance to later challenge with wild-type cells. The results aid our understanding of columnaris disease and may suggest control strategies.IMPORTANCEFlavobacterium columnare causes columnaris disease in many species of freshwater fish in the wild and in aquaculture systems. Fish mortalities resulting from columnaris disease are a major problem for aquaculture. F. columnare virulence is incompletely understood, and control measures are inadequate. Gliding motility and protein secretion have been suggested to contribute to columnaris disease, but evidence directly linking motility to disease was lacking. We isolated and analyzed mutants that were competent for secretion but defective for motility. Some of these mutants exhibited decreased virulence. Fish that had been exposed to these mutants were partially protected from later exposure to the wild type. The results contribute to our understanding of columnaris disease and may aid development of control strategies.
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Affiliation(s)
- Nicole C. Thunes
- Department of Biological Sciences, University of Wisconsin-Milwaukee, Milwaukee, Wisconsin, USA
| | - Jason P. Evenhuis
- National Center for Cool and Cold Water Aquaculture, Agricultural Research Service, USDA, Kearneysville, West Virginia, USA
| | - Ryan S. Lipscomb
- National Center for Cool and Cold Water Aquaculture, Agricultural Research Service, USDA, Kearneysville, West Virginia, USA
| | - David Pérez-Pascual
- Institut Pasteur, Université Paris-Cité, CNRS UMR 6047, Genetics of Biofilms Laboratory, Paris, France
| | - Rebecca J. Stevick
- Institut Pasteur, Université Paris-Cité, CNRS UMR 6047, Genetics of Biofilms Laboratory, Paris, France
| | - Clayton Birkett
- National Center for Cool and Cold Water Aquaculture, Agricultural Research Service, USDA, Kearneysville, West Virginia, USA
| | - Jean-Marc Ghigo
- Institut Pasteur, Université Paris-Cité, CNRS UMR 6047, Genetics of Biofilms Laboratory, Paris, France
| | - Mark J. McBride
- Department of Biological Sciences, University of Wisconsin-Milwaukee, Milwaukee, Wisconsin, USA
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Magesh S, Hurley AI, Nepper JF, Chevrette MG, Schrope JH, Li C, Beebe DJ, Handelsman J. Surface colonization by Flavobacterium johnsoniae promotes its survival in a model microbial community. mBio 2024; 15:e0342823. [PMID: 38329367 PMCID: PMC10936215 DOI: 10.1128/mbio.03428-23] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2023] [Accepted: 01/09/2024] [Indexed: 02/09/2024] Open
Abstract
Flavobacterium johnsoniae is a ubiquitous soil and rhizosphere bacterium, but despite its abundance, the factors contributing to its success in communities are poorly understood. Using a model microbial community, The Hitchhikers of the Rhizosphere (THOR), we determined the effects of colonization on the fitness of F. johnsoniae in the community. Insertion sequencing, a massively parallel transposon mutant screen, on sterile sand identified 25 genes likely to be important for surface colonization. We constructed in-frame deletions of candidate genes predicted to be involved in cell membrane biogenesis, motility, signal transduction, and transport of amino acids and lipids. All mutants poorly colonized sand, glass, and polystyrene and produced less biofilm than the wild type, indicating the importance of the targeted genes in surface colonization. Eight of the nine colonization-defective mutants were also unable to form motile biofilms or zorbs, thereby suggesting that the affected genes play a role in group movement and linking stationary and motile biofilm formation genetically. Furthermore, we showed that the deletion of colonization genes in F. johnsoniae affected its behavior and survival in THOR on surfaces, suggesting that the same traits are required for success in a multispecies microbial community. Our results provide insight into the mechanisms of surface colonization by F. johnsoniae and form the basis for further understanding its ecology in the rhizosphere. IMPORTANCE Microbial communities direct key environmental processes through multispecies interactions. Understanding these interactions is vital for manipulating microbiomes to promote health in human, environmental, and agricultural systems. However, microbiome complexity can hinder our understanding of the underlying mechanisms in microbial community interactions. As a first step toward unraveling these interactions, we explored the role of surface colonization in microbial community interactions using The Hitchhikers Of the Rhizosphere (THOR), a genetically tractable model community of three bacterial species, Flavobacterium johnsoniae, Pseudomonas koreensis, and Bacillus cereus. We identified F. johnsoniae genes important for surface colonization in solitary conditions and in the THOR community. Understanding the mechanisms that promote the success of bacteria in microbial communities brings us closer to targeted manipulations to achieve outcomes that benefit agriculture, the environment, and human health.
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Affiliation(s)
- Shruthi Magesh
- Department of Plant Pathology, Wisconsin Institute for Discovery, University of Wisconsin-Madison, Madison, Wisconsin, USA
- Microbiology Doctoral Training Program, University of Wisconsin-Madison, Madison, Wisconsin, USA
| | - Amanda I. Hurley
- Department of Plant Pathology, Wisconsin Institute for Discovery, University of Wisconsin-Madison, Madison, Wisconsin, USA
| | - Julia F. Nepper
- Department of Plant Pathology, Wisconsin Institute for Discovery, University of Wisconsin-Madison, Madison, Wisconsin, USA
| | - Marc G. Chevrette
- Department of Microbiology and Cell Science, University of Florida, Gainesville, Florida, USA
- University of Florida Genetics Institute, Gainesville, Florida, USA
| | - Jonathan H. Schrope
- Department of Biomedical Engineering, University of Wisconsin Madison, Madison, Wisconsin, USA
- Department of Pathology and Laboratory Medicine, University of Wisconsin-Madison, Madison, Wisconsin, USA
| | - Chao Li
- Carbone Cancer Center, University of Wisconsin Madison, Madison, Wisconsin, USA
| | - David J. Beebe
- Department of Biomedical Engineering, University of Wisconsin Madison, Madison, Wisconsin, USA
- Department of Pathology and Laboratory Medicine, University of Wisconsin-Madison, Madison, Wisconsin, USA
- Carbone Cancer Center, University of Wisconsin Madison, Madison, Wisconsin, USA
| | - Jo Handelsman
- Department of Plant Pathology, Wisconsin Institute for Discovery, University of Wisconsin-Madison, Madison, Wisconsin, USA
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Social Motility Assays of Flavobacterium johnsoniae. Methods Mol Biol 2023; 2646:287-298. [PMID: 36842123 DOI: 10.1007/978-1-0716-3060-0_23] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/27/2023]
Abstract
Flavobacterium johnsoniae cells move rapidly over solid surfaces by gliding motility. The collective migration of F. johnsoniae on the surfaces results in the formation of spreading colonies. Colony spreading is influenced by adhesin components on the cell surface and the concentrations of agar and glucose. For example, on nutrient-poor agar media, film-like, round spreading colonies are formed. F. johnsoniae displays at least two types of migration: small cell cluster movements leading to concentric colonies and individual cell movements leading to dendritic colonies. The methods for observing colony morphology are described in this chapter.
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Kondo Y, Ohara K, Fujii R, Nakai Y, Sato C, Naito M, Tsukuba T, Kadowaki T, Sato K. Transposon mutagenesis and genome sequencing identify two novel, tandem genes involved in the colony spreading of Flavobacterium collinsii, isolated from an ayu fish, Plecoglossus altivelis. Front Cell Infect Microbiol 2023; 13:1095919. [PMID: 36844397 PMCID: PMC9950754 DOI: 10.3389/fcimb.2023.1095919] [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: 11/11/2022] [Accepted: 01/16/2023] [Indexed: 02/12/2023] Open
Abstract
Bacteria of the family Flavobacteriaceae (flavobacteria) primarily comprise nonpathogenic bacteria that inhabit soil and water (both marine and freshwater). However, some bacterial species in the family, including Flavobacterium psychrophilum and Flavobacterium columnare, are known to be pathogenic to fish. Flavobacteria, including the abovementioned pathogenic bacteria, belong to the phylum Bacteroidota and possess two phylum-specific features, gliding motility and a protein secretion system, which are energized by a common motor complex. Herein, we focused on Flavobacterium collinsii (GiFuPREF103) isolated from a diseased fish (Plecoglossus altivelis). Genomic analysis of F. collinsii GiFuPREF103 revealed the presence of a type IX secretion system and additional genes associated with gliding motility and spreading. Using transposon mutagenesis, we isolated two mutants with altered colony morphology and colony spreading ability; these mutants had transposon insertions in pep25 and lbp26. The glycosylation material profiles revealed that these mutants lacked the high-molecular-weight glycosylated materials present in the wild-type strain. In addition, the wild-type strains exhibited fast cell population movement at the edge of the spreading colony, whereas reduced cell population behavior was observed in the pep25- and lbp26-mutant strains. In the aqueous environment, the surface layers of these mutant strains were more hydrophobic, and they formed biofilms with enhanced microcolony growth compared to those with the wild-type. In Flavobacterium johnsoniae, the Fjoh_0352 and Fjoh_0353 mutant strains were generated, which were based on the ortholog genes of pep25 and lbp26. In these F. johnsoniae mutants, as in F. collinsii GiFuPREF103, colonies with diminished spreading capacity were formed. Furthermore, cell population migration was observed at the edge of the colony in wild-type F. johnsoniae, whereas individual cells, and not cell populations, migrated in these mutant strains. The findings of the present study indicate that pep25 and lbp26 contribute to the colony spreading of F. collinsii.
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Affiliation(s)
- Yoshio Kondo
- Department of Pediatric Dentistry, Nagasaki University Graduate School of Biomedical Sciences, Nagasaki, Japan,*Correspondence: Yoshio Kondo, ; Keiko Sato,
| | - Kenichi Ohara
- Gifu Prefectural Research Institute for Fisheries and Aquatic Environments, Gifu, Japan
| | - Ryoji Fujii
- Gifu Prefectural Research Institute for Fisheries and Aquatic Environments, Gifu, Japan
| | - Yudai Nakai
- Department of Frontier Oral Science, Nagasaki University Graduate School of Biomedical Sciences, Nagasaki, Japan
| | - Chikara Sato
- School of Integrative and Global Majors (SIGMA), University of Tsukuba, Ibaraki, Japan,Biological Science Course, Graduate School of Science and Engineering, Aoyama Gakuin University, Kanagawa, Japan,Division of Immune Homeostasis, Department of Pathology and Microbiology, Nihon University School of Medicine, Tokyo, Japan,Division of Microbiology, Department of Pathology and Microbiology, Nihon University School of Medicine, Tokyo, Japan
| | - Mariko Naito
- Department of Microbiology and Oral Infection, Nagasaki University Graduate School of Biomedical Sciences, Nagasaki, Japan
| | - Takayuki Tsukuba
- Department of Dental Pharmacology, Nagasaki University Graduate School of Biomedical Sciences, Nagasaki, Japan
| | - Tomoko Kadowaki
- Department of Frontier Oral Science, Nagasaki University Graduate School of Biomedical Sciences, Nagasaki, Japan
| | - Keiko Sato
- Department of Frontier Oral Science, Nagasaki University Graduate School of Biomedical Sciences, Nagasaki, Japan,*Correspondence: Yoshio Kondo, ; Keiko Sato,
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Chodkowski JL, Shade A. A coevolution experiment between Flavobacterium johnsoniae and Burkholderia thailandensis reveals parallel mutations that reduce antibiotic susceptibility. MICROBIOLOGY (READING, ENGLAND) 2023; 169. [PMID: 36724091 DOI: 10.1099/mic.0.001267] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
One interference mechanism of bacterial competition is the production of antibiotics. Bacteria exposed to antibiotics can resist antibiotic inhibition through intrinsic or acquired mechanisms. Here, we performed a coevolution experiment to understand the long-term consequences of antibiotic production and antibiotic susceptibility for two environmental bacterial strains. We grew five independent lines of the antibiotic-producing environmental strain, Burkholderia thailandensis E264, and the antibiotic-inhibited environmental strain, Flavobacterium johnsoniae UW101, together and separately on agar plates for 7.5 months (1.5 month incubations), transferring each line five times to new agar plates. We observed that the F. johnsoniae ancestor could tolerate the B. thailandensis-produced antibiotic through efflux mechanisms, but that the coevolved lines had reduced susceptibility. We then sequenced genomes from the coevolved and monoculture F. johnsoniae lines, and uncovered mutational ramifications for the long-term antibiotic exposure. The coevolved genomes from F. johnsoniae revealed four potential mutational signatures of reduced antibiotic susceptibility that were not observed in the evolved monoculture lines. Two mutations were found in tolC: one corresponding to a 33 bp deletion and the other corresponding to a nonsynonymous mutation. A third mutation was observed as a 1 bp insertion coding for a RagB/SusD nutrient uptake protein. The last mutation was a G83R nonsynonymous mutation in acetyl-coA carboxylayse carboxyltransferase subunit alpha (AccA). Deleting the 33 bp from tolC in the F. johnsoniae ancestor reduced antibiotic susceptibility, but not to the degree observed in coevolved lines. Furthermore, the accA mutation matched a previously described mutation conferring resistance to B. thailandensis-produced thailandamide. Analysis of B. thailandensis transposon mutants for thailandamide production revealed that thailandamide was bioactive against F. johnsoniae, but also suggested that additional B. thailandensis-produced antibiotics were involved in the inhibition of F. johnsoniae. This study reveals how multi-generational interspecies interactions, mediated through chemical exchange, can result in novel interaction-specific mutations, some of which may contribute to reductions in antibiotic susceptibility.
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Affiliation(s)
- John L Chodkowski
- Department of Microbiology and Molecular Genetics, Michigan State University, East Lansing, MI 48824, USA
| | - Ashley Shade
- Department of Microbiology and Molecular Genetics, Michigan State University, East Lansing, MI 48824, USA.,Department of Plant, Soil and Microbial Sciences, Michigan State University, East Lansing, MI 48824, USA.,Program in Ecology, Evolution and Behavior, Michigan State University, East Lansing, MI 48824, USA.,Univ Lyon, CNRS, INSA Lyon, Université Claude Bernard Lyon 1, Ecole Centrale de Lyon, Ampère, UMR5005, 69134, Ecully cedex, France
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Shibata S, Tahara YO, Katayama E, Kawamoto A, Kato T, Zhu Y, Nakane D, Namba K, Miyata M, McBride MJ, Nakayama K. Filamentous structures in the cell envelope are associated with bacteroidetes gliding machinery. Commun Biol 2023; 6:94. [PMID: 36690840 PMCID: PMC9870892 DOI: 10.1038/s42003-023-04472-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2022] [Accepted: 01/12/2023] [Indexed: 01/24/2023] Open
Abstract
Many bacteria belonging to the phylum Bacteroidetes move on solid surfaces, called gliding motility. In our previous study with the Bacteroidetes gliding bacterium Flavobacterium johnsoniae, we proposed a helical loop track model, where adhesive SprB filaments are propelled along a helical loop on the cell surface. In this study, we observed the gliding cell rotating counterclockwise about its axis when viewed from the rear to the advancing direction of the cell and revealed that one labeled SprB focus sometimes overtook and passed another SprB focus that was moving in the same direction. Several electron microscopic analyses revealed the presence of a possible multi-rail structure underneath the outer membrane, which was associated with SprB filaments and contained GldJ protein. These results provide insights into the mechanism of Bacteroidetes gliding motility, in which the SprB filaments are propelled along tracks that may form a multi-rail system underneath the outer membrane. The insights may give clues as to how the SprB filaments get their driving force.
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Affiliation(s)
- Satoshi Shibata
- Department of Microbiology and Oral Infection, Graduate School of Biomedical Sciences, Nagasaki University, Nagasaki, Japan.
- Division of Bacteriology, Department of Microbiology and Immunology, Faculty of Medicine, Tottori University, Yonago, Tottori, Japan.
| | - Yuhei O Tahara
- The OCU Advanced Research Institute for Natural Science and Technology (OCARINA), Osaka Metropolitan University, Sumiyoshi-ku, Osaka, Japan
- Graduate School of Science, Osaka Metropolitan University, Sumiyoshi-ku, Osaka, Japan
| | - Eisaku Katayama
- The OCU Advanced Research Institute for Natural Science and Technology (OCARINA), Osaka Metropolitan University, Sumiyoshi-ku, Osaka, Japan
- Waseda Research Institute for Science and Engineering, Okubo Shinjyuku, Tokyo, Japan
| | - Akihiro Kawamoto
- Graduate School of Frontier Biosciences, Osaka University, Suita, Osaka, Japan
- Institute for Protein Research, Osaka University, Suita, Osaka, Japan
| | - Takayuki Kato
- Graduate School of Frontier Biosciences, Osaka University, Suita, Osaka, Japan
- Institute for Protein Research, Osaka University, Suita, Osaka, Japan
| | - Yongtao Zhu
- Department of Biological Sciences, University of Wisconsin-Milwaukee, Milwaukee, WI, 53201, USA
- Department of Biological Sciences, Xi'an Jiaotong-Liverpool University, Suzhou, Jiangsu, China
| | - Daisuke Nakane
- Department of Engineering Science, Graduate School of Informatics and Engineering, The University of Electro-Communications, Chofu, Tokyo, Japan
| | - Keiichi Namba
- Graduate School of Frontier Biosciences, Osaka University, Suita, Osaka, Japan
| | - Makoto Miyata
- The OCU Advanced Research Institute for Natural Science and Technology (OCARINA), Osaka Metropolitan University, Sumiyoshi-ku, Osaka, Japan
- Graduate School of Science, Osaka Metropolitan University, Sumiyoshi-ku, Osaka, Japan
| | - Mark J McBride
- Department of Biological Sciences, University of Wisconsin-Milwaukee, Milwaukee, WI, 53201, USA
| | - Koji Nakayama
- Department of Microbiology and Oral Infection, Graduate School of Biomedical Sciences, Nagasaki University, Nagasaki, Japan.
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Jørgensen J, Sundell K, Castillo D, Dramshøj LS, Jørgensen NB, Madsen SB, Landor L, Wiklund T, Donati VL, Madsen L, Dalsgaard I, Middelboe M. Reversible mutations in gliding motility and virulence genes: A flexible and efficient phage defence mechanism in Flavobacterium psychrophilum. Environ Microbiol 2022; 24:4915-4930. [PMID: 35837851 DOI: 10.1111/1462-2920.16126] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2022] [Revised: 06/27/2022] [Accepted: 07/04/2022] [Indexed: 01/07/2023]
Abstract
Flavobacteria are among the most important pathogens in freshwater salmonid aquaculture worldwide. Due to concerns regarding development of antibiotic resistance, phage therapy has been proposed as a solution to decrease pathogen load. However, application of phages is challenged by the development of phage resistance, and knowledge of the mechanisms and implications of phage resistance is therefore required. To study this, 27 phage-resistant isolates of F. psychrophilum were genome sequenced and characterized to identify genetic modifications and evaluate changes in phenotypic traits, including virulence against rainbow trout. Phage-resistant isolates showed reduction or loss of gliding motility, proteolytic activity, and adhesion to surfaces, and most isolates were completely non-virulent against rainbow trout fry. Genomic analysis revealed that most phage-resistant isolates had mutations in genes associated with gliding motility and virulence. Reversal of these mutations in a sub-set of isolates led to regained motility, proteolytic activity, virulence and phage susceptibility. Although costly, the fast generation of phage resistance driven by single, reversible mutations likely represents a flexible and efficient phage defence mechanism in F. psychrophilum. The results further suggest that phage administration in aquaculture systems to prevent F. psychrophilum outbreaks selects for non-virulent phage-resistant phenotypes.
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Affiliation(s)
| | - Krister Sundell
- Laboratory of Aquatic Pathobiology, Åbo Akademi University, Turku, Finland
| | - Daniel Castillo
- Department of Biology, University of Copenhagen, Helsingør, Denmark
| | - Liv S Dramshøj
- Department of Biology, University of Copenhagen, Helsingør, Denmark
| | | | - Susie B Madsen
- Department of Biology, University of Copenhagen, Helsingør, Denmark
| | - Lotta Landor
- Laboratory of Aquatic Pathobiology, Åbo Akademi University, Turku, Finland.,Department of Biological Sciences, University of Bergen, Bergen, Norway
| | - Tom Wiklund
- Laboratory of Aquatic Pathobiology, Åbo Akademi University, Turku, Finland
| | - Valentina L Donati
- National Institute of Aquatic Resources, Technical University of Denmark, Kongens Lyngby, Denmark
| | - Lone Madsen
- National Institute of Aquatic Resources, Technical University of Denmark, Kongens Lyngby, Denmark
| | - Inger Dalsgaard
- National Institute of Aquatic Resources, Technical University of Denmark, Kongens Lyngby, Denmark
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Pellizza L, Bialer MG, Sieira R, Aran M. MliR, a novel MerR-like regulator of iron homeostasis, impacts metabolism, membrane remodeling, and cell adhesion in the marine Bacteroidetes Bizionia argentinensis. Front Microbiol 2022; 13:987756. [PMID: 36118216 PMCID: PMC9478572 DOI: 10.3389/fmicb.2022.987756] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2022] [Accepted: 08/08/2022] [Indexed: 11/13/2022] Open
Abstract
The MerR family is a group of transcriptional activators with conserved N-terminal helix-turn-helix DNA binding domains and variable C-terminal effector binding regions. In most MerR proteins the effector binding domain (EBD) contains a cysteine center suited for metal binding and mediates the response to environmental stimuli, such as oxidative stress, heavy metals or antibiotics. We here present a novel transcriptional regulator classified in the MerR superfamily that lacks an EBD domain and has neither conserved metal binding sites nor cysteine residues. This regulator from the psychrotolerant bacteria Bizionia argentinensis JUB59 is involved in iron homeostasis and was named MliR (MerR-like iron responsive Regulator). In silico analysis revealed that homologs of the MliR protein are widely distributed among different bacterial species. Deletion of the mliR gene led to decreased cell growth, increased cell adhesion and filamentation. Genome-wide transcriptomic analysis showed that genes associated with iron homeostasis were downregulated in mliR-deletion mutant. Through nuclear magnetic resonance-based metabolomics, ICP-MS, fluorescence microscopy and biochemical analysis we evaluated metabolic and phenotypic changes associated with mliR deletion. This work provides the first evidence of a MerR-family regulator involved in iron homeostasis and contributes to expanding our current knowledge on relevant metabolic pathways and cell remodeling mechanisms underlying in the adaptive response to iron availability in bacteria.
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10
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Vincent MS, Comas Hervada C, Sebban-Kreuzer C, Le Guenno H, Chabalier M, Kosta A, Guerlesquin F, Mignot T, McBride MJ, Cascales E, Doan T. Dynamic proton-dependent motors power type IX secretion and gliding motility in Flavobacterium. PLoS Biol 2022; 20:e3001443. [PMID: 35333857 PMCID: PMC8986121 DOI: 10.1371/journal.pbio.3001443] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2021] [Revised: 04/06/2022] [Accepted: 03/01/2022] [Indexed: 02/06/2023] Open
Abstract
Motile bacteria usually rely on external apparatus like flagella for swimming or pili for twitching. By contrast, gliding bacteria do not rely on obvious surface appendages to move on solid surfaces. Flavobacterium johnsoniae and other bacteria in the Bacteroidetes phylum use adhesins whose movement on the cell surface supports motility. In F. johnsoniae, secretion and helicoidal motion of the main adhesin SprB are intimately linked and depend on the type IX secretion system (T9SS). Both processes necessitate the proton motive force (PMF), which is thought to fuel a molecular motor that comprises the GldL and GldM cytoplasmic membrane proteins. Here, we show that F. johnsoniae gliding motility is powered by the pH gradient component of the PMF. We further delineate the interaction network between the GldLM transmembrane helices (TMHs) and show that conserved glutamate residues in GldL TMH2 are essential for gliding motility, although having distinct roles in SprB secretion and motion. We then demonstrate that the PMF and GldL trigger conformational changes in the GldM periplasmic domain. We finally show that multiple GldLM complexes are distributed in the membrane, suggesting that a network of motors may be present to move SprB along a helical path on the cell surface. Altogether, our results provide evidence that GldL and GldM assemble dynamic membrane channels that use the proton gradient to power both T9SS-dependent secretion of SprB and its motion at the cell surface. Motile bacteria usually rely on external apparatus like flagella or pili, but gliding bacteria do not rely on obvious surface appendages for their movement. This study shows that bacteria in the phylum Bacteroidetes use proton-dependent motors to power protein secretion and gliding motility.
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Affiliation(s)
- Maxence S. Vincent
- Laboratoire d’Ingénierie des Systèmes Macromoléculaires, Institut de Microbiologie, Bioénergies et Biotechnologie, Aix-Marseille Université – CNRS UMR7255, Marseille, France
| | - Caterina Comas Hervada
- Laboratoire d’Ingénierie des Systèmes Macromoléculaires, Institut de Microbiologie, Bioénergies et Biotechnologie, Aix-Marseille Université – CNRS UMR7255, Marseille, France
| | - Corinne Sebban-Kreuzer
- Laboratoire d’Ingénierie des Systèmes Macromoléculaires, Institut de Microbiologie, Bioénergies et Biotechnologie, Aix-Marseille Université – CNRS UMR7255, Marseille, France
| | - Hugo Le Guenno
- Microscopy Core Facility, Institut de Microbiologie, Bioénergies et Biotechnologie, Aix-Marseille Université, Marseille, France
| | - Maïalène Chabalier
- Laboratoire d’Ingénierie des Systèmes Macromoléculaires, Institut de Microbiologie, Bioénergies et Biotechnologie, Aix-Marseille Université – CNRS UMR7255, Marseille, France
| | - Artemis Kosta
- Microscopy Core Facility, Institut de Microbiologie, Bioénergies et Biotechnologie, Aix-Marseille Université, Marseille, France
| | - Françoise Guerlesquin
- Laboratoire d’Ingénierie des Systèmes Macromoléculaires, Institut de Microbiologie, Bioénergies et Biotechnologie, Aix-Marseille Université – CNRS UMR7255, Marseille, France
| | - Tâm Mignot
- Laboratoire de Chimie Bactérienne, Institut de Microbiologie, Bioénergies et Biotechnologie, Aix-Marseille Université – CNRS UMR7283, Marseille, France
| | - Mark J. McBride
- Department of Biological Sciences, University of Wisconsin-Milwaukee, Milwaukee, Wisconsin, United States of America
| | - Eric Cascales
- Laboratoire d’Ingénierie des Systèmes Macromoléculaires, Institut de Microbiologie, Bioénergies et Biotechnologie, Aix-Marseille Université – CNRS UMR7255, Marseille, France
- * E-mail: (EC); (TD)
| | - Thierry Doan
- Laboratoire d’Ingénierie des Systèmes Macromoléculaires, Institut de Microbiologie, Bioénergies et Biotechnologie, Aix-Marseille Université – CNRS UMR7255, Marseille, France
- * E-mail: (EC); (TD)
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11
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The Monoheme c Subunit of Respiratory Alternative Complex III Is Not Essential for Electron Transfer to Cytochrome aa3 in Flavobacterium johnsoniae. Microbiol Spectr 2021; 9:e0013521. [PMID: 34190594 PMCID: PMC8552683 DOI: 10.1128/spectrum.00135-21] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/04/2022] Open
Abstract
Bacterial alternative complex III (ACIII) catalyzes menaquinol (MKH2) oxidation, presumably fulfilling the role of cytochromes bc1/b6f in organisms that lack these enzymes. The molecular mechanism of ACIII is unknown and so far the complex has remained inaccessible for genetic modifications. The recently solved cryo-electron microscopy (cryo-EM) structures of ACIII from Flavobacterium johnsoniae, Rhodothermus marinus, and Roseiflexus castenholzii revealed no structural similarity to cytochrome bc1/b6f and there were variations in the heme-containing subunits ActA and ActE. These data implicated intriguing alternative electron transfer paths connecting ACIII with its redox partner, and left the contributions of ActE and the terminal domain of ActA to the catalytic mechanism unclear. Here, we report genetic deletion and complementation of F. johnsoniae actA and actE and the functional implications of such modifications. Deletion of actA led to the loss of activity of cytochrome aa3 (a redox partner of ACIII in this bacterium), which confirmed that ACIII is the sole source of electrons for this complex. Deletion of actE did not impair the activity of cytochrome aa3, revealing that ActE is not required for electron transfer between ACIII and cytochrome aa3. Nevertheless, absence of ActE negatively impacted the cell growth rate, pointing toward another, yet unidentified, function of this subunit. Possible explanations for these observations, including a proposal of a split in electron paths at the ActA/ActE interface, are discussed. The described system for genetic manipulations in F. johnsoniae ACIII offers new tools for studying the molecular mechanism of operation of this enzyme. IMPORTANCE Energy conversion is a fundamental process of all organisms, realized by specialized protein complexes, one of which is alternative complex III (ACIII). ACIII is a functional analogue of well-known mitochondrial complex III, but operates according to a different, still unknown mechanism. To understand how ACIII interacts functionally with its protein partners, we developed a genetic system to mutate the Flavobacterium johnsoniae genes encoding ACIII subunits. Deletion and complementation of heme-containing subunits revealed that ACIII is the sole source of electrons for cytochrome aa3 and that one of the redox-active subunits (ActE) is dispensable for electron transfer between these complexes. This study sheds light on the operation of the supercomplex of ACIII and cytochrome aa3 and suggests a division in the electron path within ACIII. It also shows a way to manipulate protein expression levels for application in other members of the Bacteroidetes phylum.
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12
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Sato K, Naya M, Hatano Y, Kasahata N, Kondo Y, Sato M, Takebe K, Naito M, Sato C. Biofilm Spreading by the Adhesin-Dependent Gliding Motility of Flavobacterium johnsoniae: 2. Role of Filamentous Extracellular Network and Cell-to-Cell Connections at the Biofilm Surface. Int J Mol Sci 2021; 22:ijms22136911. [PMID: 34199128 PMCID: PMC8269157 DOI: 10.3390/ijms22136911] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2021] [Revised: 06/19/2021] [Accepted: 06/23/2021] [Indexed: 12/15/2022] Open
Abstract
Flavobacterium johnsoniae forms a thin spreading colony on nutrient-poor agar using gliding motility. As reported in the first paper, WT cells in the colony were sparsely embedded in self-produced extracellular polymeric matrix (EPM), while sprB cells were densely packed in immature biofilm with less matrix. The colony surface is critical for antibiotic resistance and cell survival. We have now developed the Grid Stamp-Peel method whereby the colony surface is attached to a TEM grid for negative-staining microscopy. The images showed that the top of the spreading convex WT colonies was covered by EPM with few interspersed cells. Cells exposed near the colony edge made head-to-tail and/or side-to-side contact and sometimes connected via thin filaments. Nonspreading sprB and gldG and gldK colonies had a more uniform upper surface covered by different EPMs including vesicles and filaments. The EPM of sprB, gldG, and WT colonies contained filaments ~2 nm and ~5 nm in diameter; gldK colonies did not include the latter. Every cell near the edge of WT colonies had one or two dark spots, while cells inside WT colonies and cells in SprB-, GldG-, or GldK-deficient colonies did not. Together, our results suggest that the colony surface structure depends on the capability to expand biofilm.
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Affiliation(s)
- Keiko Sato
- Department of Microbiology and Oral Infection, Graduate School of Biomedical Sciences, Nagasaki University, Nagasaki 852-8588, Japan;
- Correspondence: (K.S.); (C.S.); Tel.: +81-95-819-7649 (K.S.); +81-29-861-5562 (C.S.)
| | - Masami Naya
- Health and Medical Research Institute, National Institute of Advanced Industrial Science and Technology (AIST), Tsukuba 305-8566, Japan; (M.N.); (Y.H.); (N.K.); (M.S.)
| | - Yuri Hatano
- Health and Medical Research Institute, National Institute of Advanced Industrial Science and Technology (AIST), Tsukuba 305-8566, Japan; (M.N.); (Y.H.); (N.K.); (M.S.)
| | - Naoki Kasahata
- Health and Medical Research Institute, National Institute of Advanced Industrial Science and Technology (AIST), Tsukuba 305-8566, Japan; (M.N.); (Y.H.); (N.K.); (M.S.)
| | - Yoshio Kondo
- Department of Pediatric Dentistry, Graduate School of Biomedical Sciences, Nagasaki University, Nagasaki 852-8588, Japan;
| | - Mari Sato
- Health and Medical Research Institute, National Institute of Advanced Industrial Science and Technology (AIST), Tsukuba 305-8566, Japan; (M.N.); (Y.H.); (N.K.); (M.S.)
| | - Katsuki Takebe
- Oral and Maxillofacial Surgery II, Graduate School of Dentistry, Osaka University, Yamadaoka, Suita, Osaka 565-0871, Japan;
| | - Mariko Naito
- Department of Microbiology and Oral Infection, Graduate School of Biomedical Sciences, Nagasaki University, Nagasaki 852-8588, Japan;
| | - Chikara Sato
- Health and Medical Research Institute, National Institute of Advanced Industrial Science and Technology (AIST), Tsukuba 305-8566, Japan; (M.N.); (Y.H.); (N.K.); (M.S.)
- Correspondence: (K.S.); (C.S.); Tel.: +81-95-819-7649 (K.S.); +81-29-861-5562 (C.S.)
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13
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Large-Scale Vortices with Dynamic Rotation Emerged from Monolayer Collective Motion of Gliding Flavobacteria. J Bacteriol 2021; 203:e0007321. [PMID: 33927052 DOI: 10.1128/jb.00073-21] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
A collective motion of self-driven particles has been a fascinating subject in physics and biology. Sophisticated macroscopic behavior emerges through a population of thousands or millions of bacterial cells propelling itself by flagellar rotation and chemotactic responses. Here, we found a series of collective motions accompanying successive phase transitions for a nonflagellated rod-shaped soil bacterium, Flavobacterium johnsoniae, which was driven by a surface cell movement known as gliding motility. When we spotted the cells on an agar plate with a low level of nutrients, the bacterial community exhibited vortex patterns that spontaneously appeared as lattice and integrated into a large-scale circular plate. All patterns were exhibited with a monolayer of bacteria, which enabled us to two-dimensionally visualize an individual cell with high resolution within a wide-range pattern. The single cells moved with random orientation, but the cells that were connected with one another showed left-turn-biased trajectories in a starved environment. This feature is possibly due to the collision of cells inducing a nematic alignment of dense cells as self-propelled rods. Subsequently, each vortex oscillated independently and then transformed to the rotating mode as an independent circular plate. Notably, the rotational direction of the circular plate was counterclockwise without exception. The plates developed accompanying rotation with constant angular velocity, suggesting that the mode is an efficient strategy for bacterial survival. IMPORTANCE Self-propelled bacteria propelled by flagellar rotation often display highly organized dynamic patterns at high cell densities. Here, we found a new mode of collective motion in nonflagellated bacteria; vortex patterns spontaneously appeared as lattice and were integrated into a large-scale circular plate, comprising hundreds of thousands of cells, which exhibited unidirectional rotation in a counterclockwise manner and expanded in size on agar. A series of collective motions was driven by gliding motility of the rod-shaped soil bacterium Flavobacterium johnsoniae. In a low-nutrient environment, single cells moved with random orientation, while cells at high density moved together as a unitary cluster. This might be an efficient strategy for cells of this species to find nutrients.
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14
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Daniel C, Johanna J, Krister S, Lone M, Inger D, Tom W, Mathias M. Genome-informed approach to identify genetic determinants of Flavobacterium psychrophilum phage susceptibility. Environ Microbiol 2021; 23:4185-4199. [PMID: 33989443 DOI: 10.1111/1462-2920.15593] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2021] [Revised: 04/08/2021] [Accepted: 05/11/2021] [Indexed: 12/17/2022]
Abstract
The fish pathogen Flavobacterium psychrophilum infects farmed salmonids worldwide, and application of bacteriophages has been suggested for controlling disease outbreaks in aquaculture. Successful application of phages requires detailed knowledge about the variability in phage susceptibility of the host communities. In this study, we analysed the genetic diversity of F. psychrophilum hosts and phages from the Baltic Sea area to identify genetic determinants of phage-host interaction patterns. A host range analysis of 103 phages tested against 177 F. psychrophilum strains (18 231 phage-host interactions) identified nine phage clusters, infecting from 10% to 91% of the strain collection. The core genome-based comparison of 35 F. psychrophilum isolates revealed an extremely low overall genomic diversity (>99.5% similarity). However, a small subset of 16 ORFs, including genes involved in the type IX secretion system (T9SS), gliding motility and hypothetical cell-surface related proteins, exhibited a highly elevated genetic diversity. These specific genetic variations were linked to variability in phage infection patterns obtained from experimental studies, indicating that these genes are key determinants of phage susceptibility. These findings provide novel insights on the molecular mechanisms determining phage susceptibility in F. psychrophilum and emphasizes the importance of phages as drivers of core genomic diversity in this pathogen.
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Affiliation(s)
- Castillo Daniel
- Marine Biological Section, Department of Biology, University of Copenhagen, Helsingør, Denmark.,Instituto de Investigación Interdisciplinar en Ciencias Biomédicas SEK (I3CBSEK), Universidad SEK, Santiago, Chile
| | - Jørgensen Johanna
- Marine Biological Section, Department of Biology, University of Copenhagen, Helsingør, Denmark
| | - Sundell Krister
- Laboratory of Aquatic Pathobiology, Marine and Environmental Biology, Åbo Akademi University, Turku, Finland
| | - Madsen Lone
- Unit for Fish and Shellfish Diseases, National Institute of Aquatic Resources, Technical University of Denmark, Kongens Lyngby, Denmark
| | - Dalsgaard Inger
- Unit for Fish and Shellfish Diseases, National Institute of Aquatic Resources, Technical University of Denmark, Kongens Lyngby, Denmark
| | - Wiklund Tom
- Laboratory of Aquatic Pathobiology, Marine and Environmental Biology, Åbo Akademi University, Turku, Finland
| | - Middelboe Mathias
- Marine Biological Section, Department of Biology, University of Copenhagen, Helsingør, Denmark
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15
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Sato K, Naya M, Hatano Y, Kondo Y, Sato M, Nagano K, Chen S, Naito M, Sato C. Biofilm Spreading by the Adhesin-Dependent Gliding Motility of Flavobacterium johnsoniae. 1. Internal Structure of the Biofilm. Int J Mol Sci 2021; 22:1894. [PMID: 33672911 PMCID: PMC7918930 DOI: 10.3390/ijms22041894] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2020] [Revised: 02/03/2021] [Accepted: 02/03/2021] [Indexed: 12/19/2022] Open
Abstract
The Gram-negative bacterium Flavobacterium johnsoniae employs gliding motility to move rapidly over solid surfaces. Gliding involves the movement of the adhesin SprB along the cell surface. F. johnsoniae spreads on nutrient-poor 1% agar-PY2, forming a thin film-like colony. We used electron microscopy and time-lapse fluorescence microscopy to investigate the structure of colonies formed by wild-type (WT) F. johnsoniae and by the sprB mutant (ΔsprB). In both cases, the bacteria were buried in the extracellular polymeric matrix (EPM) covering the top of the colony. In the spreading WT colonies, the EPM included a thick fiber framework and vesicles, revealing the formation of a biofilm, which is probably required for the spreading movement. Specific paths that were followed by bacterial clusters were observed at the leading edge of colonies, and abundant vesicle secretion and subsequent matrix formation were suggested. EPM-free channels were formed in upward biofilm protrusions, probably for cell migration. In the nonspreading ΔsprB colonies, cells were tightly packed in layers and the intercellular space was occupied by less matrix, indicating immature biofilm. This result suggests that SprB is not necessary for biofilm formation. We conclude that F. johnsoniae cells use gliding motility to spread and maturate biofilms.
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Affiliation(s)
- Keiko Sato
- Department of Microbiology and Oral Infection, Graduate School of Biomedical Sciences, Nagasaki University, Nagasaki 852-8588, Japan;
| | - Masami Naya
- Health and Medical Research Institute, National Institute of Advanced Industrial Science and Technology (AIST), Tsukuba 305-8566, Japan; (M.N.); (Y.H.); (M.S.)
| | - Yuri Hatano
- Health and Medical Research Institute, National Institute of Advanced Industrial Science and Technology (AIST), Tsukuba 305-8566, Japan; (M.N.); (Y.H.); (M.S.)
| | - Yoshio Kondo
- Department of Pediatric Dentistry, Graduate School of Biomedical Sciences, Nagasaki University, Nagasaki 852-8588, Japan;
| | - Mari Sato
- Health and Medical Research Institute, National Institute of Advanced Industrial Science and Technology (AIST), Tsukuba 305-8566, Japan; (M.N.); (Y.H.); (M.S.)
| | - Keiji Nagano
- Department of Microbiology, Health Sciences University of Hokkaido, 1757 Kanazawa, Tobetsu-cho, Ishikari-gun, Hokkaido 061-0293, Japan;
| | - Shicheng Chen
- Department of Clinical and Diagnostic Sciences, School of Health Sciences, Oakland University, 433 Meadow Brook Road, Rochester, MI 48309, USA;
| | - Mariko Naito
- Department of Microbiology and Oral Infection, Graduate School of Biomedical Sciences, Nagasaki University, Nagasaki 852-8588, Japan;
| | - Chikara Sato
- Health and Medical Research Institute, National Institute of Advanced Industrial Science and Technology (AIST), Tsukuba 305-8566, Japan; (M.N.); (Y.H.); (M.S.)
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16
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Sato K, Naya M, Hatano Y, Kondo Y, Sato M, Narita Y, Nagano K, Naito M, Nakayama K, Sato C. Colony spreading of the gliding bacterium Flavobacterium johnsoniae in the absence of the motility adhesin SprB. Sci Rep 2021; 11:967. [PMID: 33441737 PMCID: PMC7807042 DOI: 10.1038/s41598-020-79762-5] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2020] [Accepted: 11/30/2020] [Indexed: 12/11/2022] Open
Abstract
Colony spreading of Flavobacterium johnsoniae is shown to include gliding motility using the cell surface adhesin SprB, and is drastically affected by agar and glucose concentrations. Wild-type (WT) and ΔsprB mutant cells formed nonspreading colonies on soft agar, but spreading dendritic colonies on soft agar containing glucose. In the presence of glucose, an initial cell growth-dependent phase was followed by a secondary SprB-independent, gliding motility-dependent phase. The branching pattern of a ΔsprB colony was less complex than the pattern formed by the WT. Mesoscopic and microstructural information was obtained by atmospheric scanning electron microscopy (ASEM) and transmission EM, respectively. In the growth-dependent phase of WT colonies, dendritic tips spread rapidly by the movement of individual cells. In the following SprB-independent phase, leading tips were extended outwards by the movement of dynamic windmill-like rolling centers, and the lipoproteins were expressed more abundantly. Dark spots in WT cells during the growth-dependent spreading phase were not observed in the SprB-independent phase. Various mutations showed that the lipoproteins and the motility machinery were necessary for SprB-independent spreading. Overall, SprB-independent colony spreading is influenced by the lipoproteins, some of which are involved in the gliding machinery, and medium conditions, which together determine the nutrient-seeking behavior.
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Affiliation(s)
- Keiko Sato
- Department of Microbiology and Oral Infection, Graduate School of Biomedical Sciences, Nagasaki University, 1-7-1 Sakamoto, Nagasaki, 852-8588, Japan.
| | - Masami Naya
- Health and Medical Research Institute, Advanced Industrial Science and Technology (AIST), Central 6, Higashi 1-1-1, Tsukuba, Ibaraki, 305-8566, Japan
| | - Yuri Hatano
- Health and Medical Research Institute, Advanced Industrial Science and Technology (AIST), Central 6, Higashi 1-1-1, Tsukuba, Ibaraki, 305-8566, Japan
| | - Yoshio Kondo
- Department of Pediatric Dentistry, Graduate School of Biomedical Sciences, Nagasaki University, 1-7-1 Sakamoto, Nagasaki, 852-8588, Japan
| | - Mari Sato
- Health and Medical Research Institute, Advanced Industrial Science and Technology (AIST), Central 6, Higashi 1-1-1, Tsukuba, Ibaraki, 305-8566, Japan
| | - Yuka Narita
- Department of Functional Bioscience, Infection Biology, Fukuoka Dental College, 2-15-1 Tamura, Sawara, Fukuoka, 814-0913, Japan
| | - Keiji Nagano
- Department of Microbiology, Health Sciences University of Hokkaido, 1757 Kanazawa, Tobetsu-cho, Ishikari-gun, Hokkaido, 061-0293, Japan
| | - Mariko Naito
- Department of Microbiology and Oral Infection, Graduate School of Biomedical Sciences, Nagasaki University, 1-7-1 Sakamoto, Nagasaki, 852-8588, Japan
| | - Koji Nakayama
- Department of Microbiology and Oral Infection, Graduate School of Biomedical Sciences, Nagasaki University, 1-7-1 Sakamoto, Nagasaki, 852-8588, Japan
| | - Chikara Sato
- Health and Medical Research Institute, Advanced Industrial Science and Technology (AIST), Central 6, Higashi 1-1-1, Tsukuba, Ibaraki, 305-8566, Japan.
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17
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Shrivastava A, Berg HC. A molecular rack and pinion actuates a cell-surface adhesin and enables bacterial gliding motility. SCIENCE ADVANCES 2020; 6:eaay6616. [PMID: 32181348 PMCID: PMC7056307 DOI: 10.1126/sciadv.aay6616] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/08/2019] [Accepted: 12/10/2019] [Indexed: 06/10/2023]
Abstract
The gliding bacterium Flavobacterium johnsoniae is known to have an adhesin, SprB, that moves along the cell surface on a spiral track. Following viscous shear, cells can be tethered by the addition of an anti-SprB antibody, causing spinning at 3 Hz. Labeling the type 9 secretion system (T9SS) with a YFP fusion of GldL showed a yellow fluorescent spot near the rotation axis, indicating that the motor driving the motion is associated with the T9SS. The distance between the rotation axis and the track (90 nm) was determined after adding a Cy3 label for SprB. A rotary motor spinning a pinion of radius 90 nm at 3 Hz would cause a spot on its periphery to move at 1.5 μm/s, the gliding speed. We suggest the pinion drives a flexible tread that carries SprB along a track fixed to the cell surface. Cells glide when this adhesin adheres to the solid substratum.
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Affiliation(s)
- Abhishek Shrivastava
- Department of Molecular and Cellular Biology, Harvard University, Cambridge, MA 02138, USA
- School of Life Sciences, Arizona State University, Tempe, AZ 85281, USA
- The Biodesign Institute, Center for Fundamental and Applied Microbiomics, Arizona State University, Tempe, AZ, 85281, USA
| | - Howard C. Berg
- Department of Molecular and Cellular Biology, Harvard University, Cambridge, MA 02138, USA
- Rowland Institute at Harvard, Cambridge, MA 02142, USA
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18
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Baez WD, Roy B, McNutt ZA, Shatoff EA, Chen S, Bundschuh R, Fredrick K. Global analysis of protein synthesis in Flavobacterium johnsoniae reveals the use of Kozak-like sequences in diverse bacteria. Nucleic Acids Res 2019; 47:10477-10488. [PMID: 31602466 PMCID: PMC6847099 DOI: 10.1093/nar/gkz855] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2019] [Revised: 09/16/2019] [Accepted: 09/30/2019] [Indexed: 12/31/2022] Open
Abstract
In all cells, initiation of translation is tuned by intrinsic features of the mRNA. Here, we analyze translation in Flavobacterium johnsoniae, a representative of the Bacteroidetes. Members of this phylum naturally lack Shine-Dalgarno (SD) sequences in their mRNA, and yet their ribosomes retain the conserved anti-SD sequence. Translation initiation is tuned by mRNA secondary structure and by the identities of several key nucleotides upstream of the start codon. Positive determinants include adenine at position -3, reminiscent of the Kozak sequence of Eukarya. Comparative analysis of Escherichia coli reveals use of the same Kozak-like sequence to enhance initiation, suggesting an ancient and widespread mechanism. Elimination of contacts between A-3 and the conserved β-hairpin of ribosomal protein uS7 fails to diminish the contribution of A-3 to initiation, suggesting an indirect mode of recognition. Also, we find that, in the Bacteroidetes, the trinucleotide AUG is underrepresented in the vicinity of the start codon, which presumably helps compensate for the absence of SD sequences in these organisms.
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Affiliation(s)
- William D Baez
- Department of Physics, The Ohio State University, Columbus, OH 43210, USA
- Center for RNA Biology, The Ohio State University, Columbus, OH 43210, USA
| | - Bappaditya Roy
- Center for RNA Biology, The Ohio State University, Columbus, OH 43210, USA
- Department of Microbiology, The Ohio State University, Columbus, OH 43210, USA
| | - Zakkary A McNutt
- Center for RNA Biology, The Ohio State University, Columbus, OH 43210, USA
- Department of Microbiology, The Ohio State University, Columbus, OH 43210, USA
- Ohio State Biochemistry Program, The Ohio State University, Columbus, OH 43210, USA
| | - Elan A Shatoff
- Department of Physics, The Ohio State University, Columbus, OH 43210, USA
- Center for RNA Biology, The Ohio State University, Columbus, OH 43210, USA
| | - Shicheng Chen
- Department of Microbiology and Molecular Genetics, Michigan State University, East Lansing, MI 48824, USA
| | - Ralf Bundschuh
- Department of Physics, The Ohio State University, Columbus, OH 43210, USA
- Center for RNA Biology, The Ohio State University, Columbus, OH 43210, USA
- Department of Chemistry and Biochemistry, Division of Hematology, Department of Internal Medicine, The Ohio State University, Columbus, OH 43210, USA
| | - Kurt Fredrick
- Center for RNA Biology, The Ohio State University, Columbus, OH 43210, USA
- Department of Microbiology, The Ohio State University, Columbus, OH 43210, USA
- Ohio State Biochemistry Program, The Ohio State University, Columbus, OH 43210, USA
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19
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The Carboxy-Terminal Region of Flavobacterium johnsoniae SprB Facilitates Its Secretion by the Type IX Secretion System and Propulsion by the Gliding Motility Machinery. J Bacteriol 2019; 201:JB.00218-19. [PMID: 31262839 DOI: 10.1128/jb.00218-19] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2019] [Accepted: 06/26/2019] [Indexed: 12/18/2022] Open
Abstract
Flavobacterium johnsoniae SprB moves rapidly along the cell surface, resulting in gliding motility. SprB secretion requires the type IX secretion system (T9SS). Proteins secreted by the T9SS typically have conserved C-terminal domains (CTDs) belonging to the type A CTD or type B CTD family. Attachment of 70- to 100-amino-acid type A CTDs to a foreign protein allows its secretion. Type B CTDs are common but have received little attention. Secretion of the foreign protein superfolder green fluorescent protein (sfGFP) fused to regions spanning the SprB type B CTD (sfGFP-CTDSprB) was analyzed. CTDs of 218 amino acids or longer resulted in secretion of sfGFP, whereas a 149-amino-acid region did not. Some sfGFP was secreted in soluble form, whereas the rest was attached on the cell surface. Surface-attached sfGFP was rapidly propelled along the cell, suggesting productive interaction with the motility machinery. This did not result in rapid cell movement, which apparently requires additional regions of SprB. Secretion of sfGFP-CTDSprB required coexpression with sprF, which lies downstream of sprB SprF is similar in sequence to Porphyromonas gingivalis PorP. Most F. johnsoniae genes encoding proteins with type B CTDs lie immediately upstream of porP/sprF-like genes. sfGFP was fused to the type B CTD from one such protein (Fjoh_3952). This resulted in secretion of sfGFP only when it was coexpressed with its cognate PorP/SprF-like protein. These results highlight the need for extended regions of type B CTDs and for coexpression with the appropriate PorP/SprF-like protein for efficient secretion and cell surface localization of cargo proteins.IMPORTANCE The F. johnsoniae gliding motility adhesin SprB is delivered to the cell surface by the type IX secretion system (T9SS) and is rapidly propelled along the cell by the motility machinery. How this 6,497-amino-acid protein interacts with the secretion and motility machines is not known. Fusion of the C-terminal 218 amino acids of SprB to a foreign cargo protein resulted in its secretion, attachment to the cell surface, and rapid movement by the motility machinery. Efficient secretion of SprB required coexpression with the outer membrane protein SprF. Secreted proteins that have sequence similarity to SprB in their C-terminal regions are common in the phylum Bacteroidetes and may have roles in adhesion, motility, and virulence.
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20
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Liu M, Tian X, Wang M, Zhu D, Wang M, Jia R, Chen S, Zhao X, Yang Q, Wu Y, Zhang S, Huang J, Tian B, Chen X, Liu Y, Zhang L, Yu Y, Biville F, Pan L, Rehman MU, Cheng A. Development of a markerless gene deletion strategy using rpsL as a counterselectable marker and characterization of the function of RA0C_1534 in Riemerella anatipestifer ATCC11845 using this strategy. PLoS One 2019; 14:e0218241. [PMID: 31181133 PMCID: PMC6557517 DOI: 10.1371/journal.pone.0218241] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2019] [Accepted: 05/28/2019] [Indexed: 12/19/2022] Open
Abstract
Riemerella anatipestifer is a gram-negative bacterium that mainly infects ducks, turkeys and other birds. In a previous study, we established a markerless mutation system based on the pheS mutant as a counterselectable marker. However, the toxic effect of p-Cl-Phe on the R. anatipestifer strain expressing the pheS mutant was weak on blood agar plates. In this study, we successfully obtained streptomycin-resistant derivative of R. anatipestifer ATCC11845 using 100 μg/mL streptomycin as a selection pressure. Then, we demonstrate that rpsL can be used as a counterselectable marker in the R. anatipestifer ATCC11845 rpsL mutant strain, namely, R. anatipestifer ATCCs. A suicide vector carrying wild-type rpsL, namely, pORS, was constructed and used for markerless deletion of the gene RA0C_1534, which encodes a putative sigma-70 family RNA polymerase sigma factor. Using rpsL as a counterselectable marker, markerless mutagenesis of RA0C_1534 was also performed based on natural transformation. R. anatipestifer ATCCsΔRA0C_1534 was more sensitive to H2O2-generated oxidative stress than R. anatipestifer ATCCs. Moreover, transcription of RA0C_1534 was upregulated under 10 mM H2O2 treatment and upon mutation of fur. These results suggest that RA0C_1534 is involved in oxidative stress response in R. anatipestifer. The markerless gene mutation method developed in this study provides new tools for investigation of the physiology and pathogenic mechanisms of this bacterium.
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Affiliation(s)
- MaFeng Liu
- Research Center of Avian Disease, College of Veterinary Medicine of Sichuan Agricultural University, Chengdu, Sichuan, P.R. China
- Institute of Preventive Veterinary Medicine, College of Veterinary Medicine of Sichuan Agricultural University, Chengdu, Sichuan, P.R. China
- Key Laboratory of Animal Disease and Human Health of Sichuan Province, Chengdu, Sichuan, P. R. China
- * E-mail: (MFL); (ACC)
| | - Xiu Tian
- Research Center of Avian Disease, College of Veterinary Medicine of Sichuan Agricultural University, Chengdu, Sichuan, P.R. China
- Institute of Preventive Veterinary Medicine, College of Veterinary Medicine of Sichuan Agricultural University, Chengdu, Sichuan, P.R. China
- Key Laboratory of Animal Disease and Human Health of Sichuan Province, Chengdu, Sichuan, P. R. China
| | - MengYi Wang
- Research Center of Avian Disease, College of Veterinary Medicine of Sichuan Agricultural University, Chengdu, Sichuan, P.R. China
- Institute of Preventive Veterinary Medicine, College of Veterinary Medicine of Sichuan Agricultural University, Chengdu, Sichuan, P.R. China
- Key Laboratory of Animal Disease and Human Health of Sichuan Province, Chengdu, Sichuan, P. R. China
| | - DeKang Zhu
- Research Center of Avian Disease, College of Veterinary Medicine of Sichuan Agricultural University, Chengdu, Sichuan, P.R. China
- Institute of Preventive Veterinary Medicine, College of Veterinary Medicine of Sichuan Agricultural University, Chengdu, Sichuan, P.R. China
- Key Laboratory of Animal Disease and Human Health of Sichuan Province, Chengdu, Sichuan, P. R. China
| | - MingShu Wang
- Research Center of Avian Disease, College of Veterinary Medicine of Sichuan Agricultural University, Chengdu, Sichuan, P.R. China
- Institute of Preventive Veterinary Medicine, College of Veterinary Medicine of Sichuan Agricultural University, Chengdu, Sichuan, P.R. China
- Key Laboratory of Animal Disease and Human Health of Sichuan Province, Chengdu, Sichuan, P. R. China
| | - RenYong Jia
- Research Center of Avian Disease, College of Veterinary Medicine of Sichuan Agricultural University, Chengdu, Sichuan, P.R. China
- Institute of Preventive Veterinary Medicine, College of Veterinary Medicine of Sichuan Agricultural University, Chengdu, Sichuan, P.R. China
- Key Laboratory of Animal Disease and Human Health of Sichuan Province, Chengdu, Sichuan, P. R. China
| | - Shun Chen
- Research Center of Avian Disease, College of Veterinary Medicine of Sichuan Agricultural University, Chengdu, Sichuan, P.R. China
- Institute of Preventive Veterinary Medicine, College of Veterinary Medicine of Sichuan Agricultural University, Chengdu, Sichuan, P.R. China
- Key Laboratory of Animal Disease and Human Health of Sichuan Province, Chengdu, Sichuan, P. R. China
| | - XinXin Zhao
- Research Center of Avian Disease, College of Veterinary Medicine of Sichuan Agricultural University, Chengdu, Sichuan, P.R. China
- Institute of Preventive Veterinary Medicine, College of Veterinary Medicine of Sichuan Agricultural University, Chengdu, Sichuan, P.R. China
- Key Laboratory of Animal Disease and Human Health of Sichuan Province, Chengdu, Sichuan, P. R. China
| | - Qiao Yang
- Research Center of Avian Disease, College of Veterinary Medicine of Sichuan Agricultural University, Chengdu, Sichuan, P.R. China
- Institute of Preventive Veterinary Medicine, College of Veterinary Medicine of Sichuan Agricultural University, Chengdu, Sichuan, P.R. China
- Key Laboratory of Animal Disease and Human Health of Sichuan Province, Chengdu, Sichuan, P. R. China
| | - Ying Wu
- Research Center of Avian Disease, College of Veterinary Medicine of Sichuan Agricultural University, Chengdu, Sichuan, P.R. China
- Institute of Preventive Veterinary Medicine, College of Veterinary Medicine of Sichuan Agricultural University, Chengdu, Sichuan, P.R. China
- Key Laboratory of Animal Disease and Human Health of Sichuan Province, Chengdu, Sichuan, P. R. China
| | - ShaQiu Zhang
- Research Center of Avian Disease, College of Veterinary Medicine of Sichuan Agricultural University, Chengdu, Sichuan, P.R. China
- Institute of Preventive Veterinary Medicine, College of Veterinary Medicine of Sichuan Agricultural University, Chengdu, Sichuan, P.R. China
- Key Laboratory of Animal Disease and Human Health of Sichuan Province, Chengdu, Sichuan, P. R. China
| | - Juan Huang
- Research Center of Avian Disease, College of Veterinary Medicine of Sichuan Agricultural University, Chengdu, Sichuan, P.R. China
- Institute of Preventive Veterinary Medicine, College of Veterinary Medicine of Sichuan Agricultural University, Chengdu, Sichuan, P.R. China
- Key Laboratory of Animal Disease and Human Health of Sichuan Province, Chengdu, Sichuan, P. R. China
| | - Bin Tian
- Research Center of Avian Disease, College of Veterinary Medicine of Sichuan Agricultural University, Chengdu, Sichuan, P.R. China
- Institute of Preventive Veterinary Medicine, College of Veterinary Medicine of Sichuan Agricultural University, Chengdu, Sichuan, P.R. China
- Key Laboratory of Animal Disease and Human Health of Sichuan Province, Chengdu, Sichuan, P. R. China
| | - XiaoYue Chen
- Research Center of Avian Disease, College of Veterinary Medicine of Sichuan Agricultural University, Chengdu, Sichuan, P.R. China
- Key Laboratory of Animal Disease and Human Health of Sichuan Province, Chengdu, Sichuan, P. R. China
| | - YunYa Liu
- Research Center of Avian Disease, College of Veterinary Medicine of Sichuan Agricultural University, Chengdu, Sichuan, P.R. China
- Institute of Preventive Veterinary Medicine, College of Veterinary Medicine of Sichuan Agricultural University, Chengdu, Sichuan, P.R. China
- Key Laboratory of Animal Disease and Human Health of Sichuan Province, Chengdu, Sichuan, P. R. China
| | - Ling Zhang
- Research Center of Avian Disease, College of Veterinary Medicine of Sichuan Agricultural University, Chengdu, Sichuan, P.R. China
- Key Laboratory of Animal Disease and Human Health of Sichuan Province, Chengdu, Sichuan, P. R. China
| | - YanLing Yu
- Research Center of Avian Disease, College of Veterinary Medicine of Sichuan Agricultural University, Chengdu, Sichuan, P.R. China
- Key Laboratory of Animal Disease and Human Health of Sichuan Province, Chengdu, Sichuan, P. R. China
| | - Francis Biville
- Unité des Infections Bactériennes Invasives, Département Infection et Epidémiologie, Institut Pasteur, Paris, France
| | - LeiChang Pan
- Research Center of Avian Disease, College of Veterinary Medicine of Sichuan Agricultural University, Chengdu, Sichuan, P.R. China
- Institute of Preventive Veterinary Medicine, College of Veterinary Medicine of Sichuan Agricultural University, Chengdu, Sichuan, P.R. China
- Key Laboratory of Animal Disease and Human Health of Sichuan Province, Chengdu, Sichuan, P. R. China
| | - Mujeeb Ur Rehman
- Research Center of Avian Disease, College of Veterinary Medicine of Sichuan Agricultural University, Chengdu, Sichuan, P.R. China
- Institute of Preventive Veterinary Medicine, College of Veterinary Medicine of Sichuan Agricultural University, Chengdu, Sichuan, P.R. China
- Key Laboratory of Animal Disease and Human Health of Sichuan Province, Chengdu, Sichuan, P. R. China
| | - AnChun Cheng
- Research Center of Avian Disease, College of Veterinary Medicine of Sichuan Agricultural University, Chengdu, Sichuan, P.R. China
- Institute of Preventive Veterinary Medicine, College of Veterinary Medicine of Sichuan Agricultural University, Chengdu, Sichuan, P.R. China
- Key Laboratory of Animal Disease and Human Health of Sichuan Province, Chengdu, Sichuan, P. R. China
- * E-mail: (MFL); (ACC)
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Imamura K, Sato K, Narita Y, Kondo Y, Nakane D, Naito M, Fujiwara T, Nakayama K. Identification of a major glucose transporter in Flavobacterium johnsoniae: Inhibition of F. johnsoniae colony spreading by glucose uptake. Microbiol Immunol 2018; 62:507-516. [PMID: 29932229 DOI: 10.1111/1348-0421.12633] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2018] [Revised: 05/27/2018] [Accepted: 06/07/2018] [Indexed: 11/28/2022]
Abstract
Many members of the phylum Bacteroidetes, such as Flavobacterium johnsoniae, can glide over a solid surface: an ability called gliding motility. It can be usually observed on agar plates as thin, flat, spreading colonies with irregular, feathery edges; this phenomenon is called colony spreading. Colony spreading of F. johnsoniae on 1.5% agar plates containing poor nutrients is dose-dependently inhibited by addition of D-glucose, as previously reported. Accordingly, here, we created mutants (by transposon mutagenesis) that partially suppressed glucose-mediated inhibition of colony spreading. Among the isolates, we found that one had a transposon insertion in Fjoh_4565, tentatively named mfsA, which encodes a major facilitator superfamily (MFS) transporter previously shown to be required for growth on glucose, N-acetyl-glucosamine, and chitin. We constructed an mfsA deletion mutant and found that the mutant showed no glucose-mediated acceleration of growth or glucose uptake. The mfsA gene complemented the phenotype of a glucose-negative Escherichia coli. These results suggest that the mfsA gene encodes the sole MFS transporter of glucose in F. johnsoniae and that glucose uptake is partially required for the glucose-mediated inhibition of F. johnsoniae colony spreading.
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Affiliation(s)
- Keigo Imamura
- Department of Microbiology and Oral Infection, Graduate School of Biomedical Sciences, Nagasaki University, 1-7-1 Sakamoto, Nagasaki 852-8588, Japan.,Department of Pediatric Dentistry, Graduate School of Biomedical Sciences, Nagasaki University, 1-7-1 Sakamoto, Nagasaki 852-8588, Japan
| | - Keiko Sato
- Department of Microbiology and Oral Infection, Graduate School of Biomedical Sciences, Nagasaki University, 1-7-1 Sakamoto, Nagasaki 852-8588, Japan
| | - Yuka Narita
- Department of Microbiology and Oral Infection, Graduate School of Biomedical Sciences, Nagasaki University, 1-7-1 Sakamoto, Nagasaki 852-8588, Japan
| | - Yoshio Kondo
- Department of Pediatric Dentistry, Graduate School of Biomedical Sciences, Nagasaki University, 1-7-1 Sakamoto, Nagasaki 852-8588, Japan
| | - Daisuke Nakane
- Department of Physics, Gakushuin University, 1-5-1 Mejiro, Toshima-ku, Tokyo 171-8588, Japan
| | - Mariko Naito
- Department of Microbiology and Oral Infection, Graduate School of Biomedical Sciences, Nagasaki University, 1-7-1 Sakamoto, Nagasaki 852-8588, Japan
| | - Taku Fujiwara
- Department of Pediatric Dentistry, Graduate School of Biomedical Sciences, Nagasaki University, 1-7-1 Sakamoto, Nagasaki 852-8588, Japan
| | - Koji Nakayama
- Department of Microbiology and Oral Infection, Graduate School of Biomedical Sciences, Nagasaki University, 1-7-1 Sakamoto, Nagasaki 852-8588, Japan
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22
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Novel Method Reveals a Narrow Phylogenetic Distribution of Bacterial Dispersers in Environmental Communities Exposed to Low-Hydration Conditions. Appl Environ Microbiol 2018; 84:AEM.02857-17. [PMID: 29374034 DOI: 10.1128/aem.02857-17] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2017] [Accepted: 01/14/2018] [Indexed: 12/20/2022] Open
Abstract
In this study, we developed a method that provides profiles of community-level surface dispersal from environmental samples under controlled hydration conditions and enables us to isolate and uncover the diversity of the fastest bacterial dispersers. The method expands on the porous surface model (PSM), previously used to monitor the dispersal of individual bacterial strains in liquid films at the surface of a porous ceramic disc. The novel procedure targets complex communities and captures the dispersed bacteria on a solid medium for growth and detection. The method was first validated by distinguishing motile Pseudomonas putida and Flavobacterium johnsoniae strains from their nonmotile mutants. Applying the method to soil and lake water bacterial communities showed that community-scale dispersal declined as conditions became drier. However, for both communities, dispersal was detected even under low-hydration conditions (matric potential, -3.1 kPa) previously proven too dry for P. putida strain KT2440 motility. We were then able to specifically recover and characterize the fastest dispersers from the inoculated communities. For both soil and lake samples, 16S rRNA gene amplicon sequencing revealed that the fastest dispersers were substantially less diverse than the total communities. The dispersing fraction of the soil microbial community was dominated by Pseudomonas species cells, which increased in abundance under low-hydration conditions, while the dispersing fraction of the lake community was dominated by Aeromonas species cells and, under wet conditions (-0.5 kPa), also by Exiguobacterium species cells. The results gained in this study bring us a step closer to assessing the dispersal ability within complex communities under environmentally relevant conditions.IMPORTANCE Dispersal is a key process of bacterial community assembly, and yet, very few attempts have been made to assess bacterial dispersal at the community level, as the focus has previously been on pure-culture studies. A crucial factor for dispersal in habitats where hydration conditions vary, such as soils, is the thickness of the liquid films surrounding solid surfaces, but little is known about how the ability to disperse in such films varies within bacterial communities. Therefore, we developed a method to profile community dispersal and identify fast dispersers on a rough surface resembling soil surfaces. Our results suggest that within the motile fraction of a bacterial community, only a minority of the bacterial types are able to disperse in the thinnest liquid films. During dry periods, these efficient dispersers can gain a significant fitness advantage through their ability to colonize new habitats ahead of the rest of the community.
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23
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Johnston JJ, Shrivastava A, McBride MJ. Untangling Flavobacterium johnsoniae Gliding Motility and Protein Secretion. J Bacteriol 2018; 200:e00362-17. [PMID: 29109184 PMCID: PMC5738736 DOI: 10.1128/jb.00362-17] [Citation(s) in RCA: 27] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2017] [Accepted: 10/26/2017] [Indexed: 12/28/2022] Open
Abstract
Flavobacterium johnsoniae exhibits rapid gliding motility over surfaces. At least 20 genes are involved in this process. Seven of these, gldK, gldL, gldM, gldN, sprA, sprE, and sprT, encode proteins of the type IX protein secretion system (T9SS). The T9SS is required for surface localization of the motility adhesins SprB and RemA, and for secretion of the soluble chitinase ChiA. Here, we demonstrate that the gliding motility proteins GldA, GldB, GldD, GldF, GldH, GldI, and GldJ are also essential for secretion. Cells with mutations in the genes encoding any of these seven proteins had normal levels of gldK mRNA but dramatically reduced levels of the GldK protein, which may explain the secretion defects of the motility mutants. GldJ is necessary for stable accumulation of GldK, and each mutant lacked the GldJ protein. F. johnsoniae cells that produced truncated GldJ, lacking eight to 13 amino acids from the C terminus, accumulated GldK but were deficient in gliding motility. SprB was secreted by these cells but was not propelled along their surfaces. This C-terminal region of GldJ is thus required for gliding motility but not for secretion. The identification of mutants that are defective for motility but competent for secretion begins to untangle the F. johnsoniae gliding motility machinery from the T9SS.IMPORTANCE Many members of the phylum Bacteroidetes secrete proteins using T9SSs. T9SSs appear to be confined to members of this phylum. Many of these bacteria also glide rapidly over surfaces using a motility machine that is also confined to the Bacteroidetes and appears to be intertwined with the T9SS. This study identifies F. johnsoniae proteins that are required for both T9SS function and gliding motility. It also provides an explanation for the link between secretion and gliding and identifies mutants with defects in motility but not secretion.
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Affiliation(s)
- Joseph J Johnston
- Department of Biological Sciences, University of Wisconsin-Milwaukee, Milwaukee, Wisconsin, USA
| | - Abhishek Shrivastava
- Department of Biological Sciences, University of Wisconsin-Milwaukee, Milwaukee, Wisconsin, USA
| | - Mark J McBride
- Department of Biological Sciences, University of Wisconsin-Milwaukee, Milwaukee, Wisconsin, USA
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24
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Pérez-Pascual D, Rochat T, Kerouault B, Gómez E, Neulat-Ripoll F, Henry C, Quillet E, Guijarro JA, Bernardet JF, Duchaud E. More Than Gliding: Involvement of GldD and GldG in the Virulence of Flavobacterium psychrophilum. Front Microbiol 2017; 8:2168. [PMID: 29163446 PMCID: PMC5682007 DOI: 10.3389/fmicb.2017.02168] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2017] [Accepted: 10/23/2017] [Indexed: 12/17/2022] Open
Abstract
A fascinating characteristic of most members of the genus Flavobacterium is their ability to move over surfaces by gliding motility. Flavobacterium psychrophilum, an important pathogen of farmed salmonids worldwide, contains in its genome the 19 gld and spr genes shown to be required for gliding or spreading in Flavobacterium johnsoniae; however, their relative role in its lifestyle remains unknown. In order to address this issue, two spreading deficient mutants were produced as part of a Tn4351 mutant library in F. psychrophilum strain THCO2-90. The transposons were inserted in gldD and gldG genes. While the wild-type strain is proficient in adhesion, biofilm formation and displays strong proteolytic activity, both mutants lost these characteristics. Extracellular proteome comparisons revealed important modifications for both mutants, with a significant reduction of the amounts of proteins likely transported through the outer membrane by the Type IX secretion system, indicating that GldD and GldG proteins are required for an effective activity of this system. In addition, a significant decrease in virulence was observed using rainbow trout bath and injection infection models. Our results reveal additional roles of gldD and gldG genes that are likely of importance for the F. psychrophilum lifestyle, including virulence.
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Affiliation(s)
- David Pérez-Pascual
- Virologie et Immunologie Moléculaires, Institut National de la Recherche Agronomique, Université Paris-Saclay, Jouy-en-Josas, France
| | - Tatiana Rochat
- Virologie et Immunologie Moléculaires, Institut National de la Recherche Agronomique, Université Paris-Saclay, Jouy-en-Josas, France
| | - Brigitte Kerouault
- Virologie et Immunologie Moléculaires, Institut National de la Recherche Agronomique, Université Paris-Saclay, Jouy-en-Josas, France
| | - Esther Gómez
- Área de Microbiología, Departamento de Biología Funcional, Facultad de Medicina, Instituto de Biotecnología de Asturias (IUBA), Universidad de Oviedo, Oviedo, Spain
| | - Fabienne Neulat-Ripoll
- Virologie et Immunologie Moléculaires, Institut National de la Recherche Agronomique, Université Paris-Saclay, Jouy-en-Josas, France
| | - Celine Henry
- PAPPSO, Micalis Institute, Institut National de la Recherche Agronomique, AgroParisTech, Université Paris-Saclay, Jouy-en-Josas, France
| | - Edwige Quillet
- GABI, Institut National de la Recherche Agronomique, Université Paris-Saclay, Jouy-en-Josas, France
| | - Jose A Guijarro
- Área de Microbiología, Departamento de Biología Funcional, Facultad de Medicina, Instituto de Biotecnología de Asturias (IUBA), Universidad de Oviedo, Oviedo, Spain
| | - Jean F Bernardet
- Virologie et Immunologie Moléculaires, Institut National de la Recherche Agronomique, Université Paris-Saclay, Jouy-en-Josas, France
| | - Eric Duchaud
- Virologie et Immunologie Moléculaires, Institut National de la Recherche Agronomique, Université Paris-Saclay, Jouy-en-Josas, France
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25
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The unusual cellulose utilization system of the aerobic soil bacterium Cytophaga hutchinsonii. Appl Microbiol Biotechnol 2017; 101:7113-7127. [PMID: 28849247 DOI: 10.1007/s00253-017-8467-2] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2017] [Accepted: 08/05/2017] [Indexed: 10/19/2022]
Abstract
Cellulolytic microorganisms play important roles in global carbon cycling and have evolved diverse strategies to digest cellulose. Some are 'generous,' releasing soluble sugars from cellulose extracellularly to feed both themselves and their neighbors. The gliding soil bacterium Cytophaga hutchinsonii exhibits a more 'selfish' strategy. It digests crystalline cellulose using cell-associated cellulases and releases little soluble sugar outside of the cell. The mechanism of C. hutchinsonii cellulose utilization is still poorly understood. In this review, we discuss novel aspects of the C. hutchinsonii cellulolytic system. Recently developed genetic manipulation tools allowed the identification of proteins involved in C. hutchinsonii cellulose utilization. These include periplasmic and cell-surface endoglucanases and novel cellulose-binding proteins. The recently discovered type IX secretion system is needed for cellulose utilization and appears to deliver some of the cellulolytic enzymes and other proteins to the cell surface. The requirement for periplasmic endoglucanases for cellulose utilization is unusual and suggests that cello-oligomers must be imported across the outer membrane before being further digested. Cellobiohydrolases or other predicted processive cellulases that play important roles in many other cellulolytic bacteria appear to be absent in C. hutchinsonii. Cells of C. hutchinsonii attach to and glide along cellulose fibers, which may allow them to find sites most amenable to attack. A model of C. hutchinsonii cellulose utilization summarizing recent progress is proposed.
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26
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Zhu Y, Thomas F, Larocque R, Li N, Duffieux D, Cladière L, Souchaud F, Michel G, McBride MJ. Genetic analyses unravel the crucial role of a horizontally acquired alginate lyase for brown algal biomass degradation by Zobellia galactanivorans. Environ Microbiol 2017; 19:2164-2181. [PMID: 28205313 DOI: 10.1111/1462-2920.13699] [Citation(s) in RCA: 49] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2016] [Revised: 01/30/2017] [Accepted: 02/09/2017] [Indexed: 11/30/2022]
Abstract
Comprehension of the degradation of macroalgal polysaccharides suffers from the lack of genetic tools for model marine bacteria, despite their importance for coastal ecosystem functions. We developed such tools for Zobellia galactanivorans, an algae-associated flavobacterium that digests many polysaccharides, including alginate. These tools were used to investigate the biological role of AlyA1, the only Z. galactanivorans alginate lyase known to be secreted in soluble form and to have a recognizable carbohydrate-binding domain. A deletion mutant, ΔalyA1, grew as well as the wild type on soluble alginate but was deficient in soluble secreted alginate lyase activity and in digestion of and growth on alginate gels and algal tissues. Thus, AlyA1 appears to be essential for optimal attack of alginate in intact cell walls. alyA1 appears to have been recently acquired via horizontal transfer from marine Actinobacteria, conferring an adaptive advantage that might benefit other algae-associated bacteria by exposing new substrate niches. The genetic tools described here function in diverse members of the phylum Bacteroidetes and should facilitate analyses of polysaccharide degradation systems and many other processes in these common but understudied bacteria.
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Affiliation(s)
- Yongtao Zhu
- Department of Biological Sciences, University of Wisconsin-Milwaukee, P. O. Box 413, Milwaukee, WI, 53201, USA
| | - François Thomas
- Integrative Biology of Marine Models, Sorbonne Université, UPMC, Centre National de la Recherche Scientifique, UMR 8227, Station Biologique de Roscoff, Roscoff, France
| | - Robert Larocque
- Integrative Biology of Marine Models, Sorbonne Université, UPMC, Centre National de la Recherche Scientifique, UMR 8227, Station Biologique de Roscoff, Roscoff, France
| | - Nan Li
- State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, Hubei Province, 430072, China
| | - Delphine Duffieux
- Integrative Biology of Marine Models, Sorbonne Université, UPMC, Centre National de la Recherche Scientifique, UMR 8227, Station Biologique de Roscoff, Roscoff, France
| | - Lionel Cladière
- Integrative Biology of Marine Models, Sorbonne Université, UPMC, Centre National de la Recherche Scientifique, UMR 8227, Station Biologique de Roscoff, Roscoff, France
| | - Florent Souchaud
- Integrative Biology of Marine Models, Sorbonne Université, UPMC, Centre National de la Recherche Scientifique, UMR 8227, Station Biologique de Roscoff, Roscoff, France
| | - Gurvan Michel
- Integrative Biology of Marine Models, Sorbonne Université, UPMC, Centre National de la Recherche Scientifique, UMR 8227, Station Biologique de Roscoff, Roscoff, France
| | - Mark J McBride
- Department of Biological Sciences, University of Wisconsin-Milwaukee, P. O. Box 413, Milwaukee, WI, 53201, USA
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27
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Comparative Analysis of Cellulophaga algicola and Flavobacterium johnsoniae Gliding Motility. J Bacteriol 2016; 198:1743-1754. [PMID: 27044627 DOI: 10.1128/jb.01020-15] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2015] [Accepted: 03/30/2016] [Indexed: 01/24/2023] Open
Abstract
UNLABELLED Gliding motility is common in members of the phylum Bacteroidetes, including Flavobacterium johnsoniae and Cellulophaga algicola. F. johnsoniae gliding has been extensively studied and involves rapid movement of the cell surface adhesin SprB. Genetic analysis of C. algicola allowed a comparative analysis of gliding. Sixty-three HimarEm1-induced mutants that formed nonspreading colonies were characterized. Each had an insertion in an ortholog of an F. johnsoniae motility gene, highlighting similarities between the motility systems. Differences were also observed. C. algicola lacks orthologs of the F. johnsoniae motility genes gldA, gldF, and gldG that are thought to encode the components of an ATP-binding cassette (ABC) transporter. In addition, mutations in any of 12 F. johnsoniae gld genes result in complete loss of motility, whereas all C. algicola gld mutants retained slight residual motility. This may indicate that C. algicola has multiple motility systems, that the motility proteins exhibit partial redundancy of function, or that essential components of the motility machinery of both C. algicola and F. johnsoniae remain to be discovered. IMPORTANCE The development of genetic tools for C. algicola and comparative analysis of F. johnsoniae and C. algicola motility mutants identified similarities and differences between their gliding motility machineries. Gliding motility is common in the phylum Bacteroidetes Proteins that are important for gliding in both C. algicola and F. johnsoniae are potential core components of the Bacteroidetes gliding motility machinery.
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28
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Larsbrink J, Zhu Y, Kharade SS, Kwiatkowski KJ, Eijsink VGH, Koropatkin NM, McBride MJ, Pope PB. A polysaccharide utilization locus from Flavobacterium johnsoniae enables conversion of recalcitrant chitin. BIOTECHNOLOGY FOR BIOFUELS 2016; 9:260. [PMID: 27933102 PMCID: PMC5127042 DOI: 10.1186/s13068-016-0674-z] [Citation(s) in RCA: 59] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/14/2016] [Accepted: 11/17/2016] [Indexed: 05/08/2023]
Abstract
BACKGROUND Chitin is the second most abundant polysaccharide on earth and as such a great target for bioconversion applications. The phylum Bacteroidetes is one of nature's most ubiquitous bacterial lineages and is essential in the global carbon cycle with many members being highly efficient degraders of complex carbohydrates. However, despite their specialist reputation in carbohydrate conversion, mechanisms for degrading recalcitrant crystalline polysaccharides such as chitin and cellulose are hitherto unknown. RESULTS Here we describe a complete functional analysis of a novel polysaccharide utilization locus (PUL) in the soil Bacteroidete Flavobacterium johnsoniae, tailored for conversion of chitin. The F. johnsoniae chitin utilization locus (ChiUL) consists of eleven contiguous genes encoding carbohydrate capture and transport proteins, enzymes, and a two-component sensor-regulator system. The key chitinase (ChiA) encoded by ChiUL is atypical in terms of known Bacteroidetes-affiliated PUL mechanisms as it is not anchored to the outer cell membrane and consists of multiple catalytic domains. We demonstrate how the extraordinary hydrolytic efficiency of ChiA derives from synergy between its multiple chitinolytic (endo- and exo-acting) and previously unidentified chitin-binding domains. Reverse genetics show that ChiA and PUL-encoded proteins involved in sugar binding, import, and chitin sensing are essential for efficient chitin utilization. Surprisingly, the ChiUL encodes two pairs of SusC/D-like outer membrane proteins. Ligand-binding and structural studies revealed functional differences between the two SusD-like proteins that enhance scavenging of chitin from the environment. The combined results from this study provide insight into the mechanisms employed by Bacteroidetes to degrade recalcitrant polysaccharides and reveal important novel aspects of the PUL paradigm. CONCLUSIONS By combining reverse genetics to map essential PUL genes, structural studies on outer membrane chitin-binding proteins, and enzymology, we provide insight into the mechanisms employed by Bacteroidetes to degrade recalcitrant polysaccharides and introduce a new saccharolytic mechanism used by the phylum Bacteroidetes. The presented discovery and analysis of the ChiUL will greatly benefit future enzyme discovery efforts as well as studies regarding enzymatic intramolecular synergism.
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Affiliation(s)
- Johan Larsbrink
- Department of Chemistry, Biotechnology and Food Science, Norwegian University of Life Sciences (NMBU), 1432 Ås, Norway
- Wallenberg Wood Science Center, Division of Industrial Biotechnology, Department of Biology and Biological Engineering, Chalmers University of Technology, 412 96 Gothenburg, Sweden
| | - Yongtao Zhu
- Department of Biological Sciences, University of Wisconsin—Milwaukee, Milwaukee, WI 53201 USA
| | - Sampada S. Kharade
- Department of Biological Sciences, University of Wisconsin—Milwaukee, Milwaukee, WI 53201 USA
| | - Kurt J. Kwiatkowski
- Department of Microbiology and Immunology, University of Michigan Medical School, Ann Arbor, MI 48109 USA
| | - Vincent G. H. Eijsink
- Department of Chemistry, Biotechnology and Food Science, Norwegian University of Life Sciences (NMBU), 1432 Ås, Norway
| | - Nicole M. Koropatkin
- Department of Microbiology and Immunology, University of Michigan Medical School, Ann Arbor, MI 48109 USA
| | - Mark J. McBride
- Department of Biological Sciences, University of Wisconsin—Milwaukee, Milwaukee, WI 53201 USA
| | - Phillip B. Pope
- Department of Chemistry, Biotechnology and Food Science, Norwegian University of Life Sciences (NMBU), 1432 Ås, Norway
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Gliniewicz K, Wildung M, Orfe LH, Wiens GD, Cain KD, Lahmers KK, Snekvik KR, Call DR. Potential mechanisms of attenuation for rifampicin-passaged strains of Flavobacterium psychrophilum. BMC Microbiol 2015; 15:179. [PMID: 26377311 PMCID: PMC4571129 DOI: 10.1186/s12866-015-0518-1] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2014] [Accepted: 09/10/2015] [Indexed: 11/21/2022] Open
Abstract
Background Flavobacterium psychrophilum is the etiologic agent of bacterial coldwater disease in salmonids. Earlier research showed that a rifampicin-passaged strain of F. psychrophilum (CSF 259-93B.17) caused no disease in rainbow trout (Oncorhynchus mykiss, Walbaum) while inducing a protective immune response against challenge with the virulent CSF 259–93 strain. We hypothesized that rifampicin passage leads to an accumulation of genomic mutations that, by chance, reduce virulence. To assess the pattern of phenotypic and genotypic changes associated with passage, we examined proteomic, LPS and single-nucleotide polymorphism (SNP) differences for two F. psychrophilum strains (CSF 259–93 and THC 02–90) that were passaged with and without rifampicin selection. Results Rifampicin resistance was conveyed by expected mutations in rpoB, although affecting different DNA bases depending on the strain. One rifampicin-passaged CSF 259–93 strain (CR) was attenuated (4 % mortality) in challenged fish, but only accumulated eight nonsynonymous SNPs compared to the parent strain. A CSF 259–93 strain passaged without rifampicin (CN) accumulated five nonsynonymous SNPs and was partially attenuated (28 % mortality) compared to the parent strain (54.5 % mortality). In contrast, there were no significant change in fish mortalities among THC 02–90 wild-type and passaged strains, despite numerous SNPs accumulated during passage with (n = 174) and without rifampicin (n = 126). While only three missense SNPs were associated with attenuation, a Ser492Phe rpoB mutation in the CR strain may contribute to further attenuation. All strains except CR retained a gliding motility phenotype. Few proteomic differences were observed by 2D SDS-PAGE and there were no apparent changes in LPS between strains. Comparative methylome analysis of two strains (CR and TR) identified no shared methylation motifs for these two strains. Conclusion Multiple genomic changes arose during passage experiments with rifampicin selection pressure. Consistent with our hypothesis, unique strain-specific mutations were detected for the fully attenuated (CR), partially attenuated (CN) and another fully attenuated strain (B17). Electronic supplementary material The online version of this article (doi:10.1186/s12866-015-0518-1) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Karol Gliniewicz
- Department of Veterinary Microbiology and Pathology, Washington State University, Pullman, WA, USA. .,Present address: Department of Biological Sciences, University of Idaho, Moscow, Idaho, USA.
| | - Mark Wildung
- Molecular Biology and Genomics Core, Washington State University, Pullman, WA, USA.
| | - Lisa H Orfe
- Paul G. Allen School for Global Animal Health, Washington State University, Pullman, WA, USA.
| | - Gregory D Wiens
- USDA-ARS-National Center for Cool and Cold Water Aquaculture, Leetown, WV, USA.
| | - Kenneth D Cain
- Department of Fish and Wildlife Resources, University of Idaho, Moscow, ID, USA.
| | - Kevin K Lahmers
- Department of Biomedical Sciences and Pathobiology, Virginia Polytechnic Institute and State University, Blacksburg, VA, USA. .,Paul G. Allen School for Global Animal Health, Washington State University, Pullman, WA, USA.
| | - Kevin R Snekvik
- Department of Veterinary Microbiology and Pathology, Washington State University, Pullman, WA, USA. .,Washington Animal Disease Diagnostic Laboratory, Washington State University, Pullman, WA, USA.
| | - Douglas R Call
- Department of Veterinary Microbiology and Pathology, Washington State University, Pullman, WA, USA. .,Paul G. Allen School for Global Animal Health, Washington State University, Pullman, WA, USA.
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30
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Gene deletion strategy to examine the involvement of the two chondroitin lyases in Flavobacterium columnare virulence. Appl Environ Microbiol 2015; 81:7394-402. [PMID: 26253667 DOI: 10.1128/aem.01586-15] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2015] [Accepted: 08/06/2015] [Indexed: 11/20/2022] Open
Abstract
Flavobacterium columnare is an important bacterial pathogen of freshwater fish that causes high mortality of infected fish and heavy economic losses in aquaculture. The pathogenesis of this bacterium is poorly understood, in part due to the lack of efficient methods for genetic manipulation. In this study, a gene deletion strategy was developed and used to determine the relationship between the production of chondroitin lyases and virulence. The F. johnsoniae ompA promoter (PompA) was fused to sacB to construct a counterselectable marker for F. columnare. F. columnare carrying PompA-sacB failed to grow on media containing 10% sucrose. A suicide vector carrying PompA-sacB was constructed, and a gene deletion strategy was developed. Using this approach, the chondroitin lyase-encoding genes, cslA and cslB, were deleted. The ΔcslA and ΔcslB mutants were both partially deficient in digestion of chondroitin sulfate A, whereas a double mutant (ΔcslA ΔcslB) was completely deficient in chondroitin lyase activity. Cells of F. columnare wild-type strain G4 and of the chondroitin lyase-deficient ΔcslA ΔcslB mutant exhibited similar levels of virulence toward grass carp in single-strain infections. Coinfections, however, revealed a competitive advantage for the wild type over the chondroitin lyase mutant. The results indicate that chondroitin lyases are not essential virulence factors of F. columnare but may contribute to the ability of the pathogen to compete and cause disease in natural infections. The gene deletion method developed in this study may be employed to investigate the virulence factors of this bacterium and may have wide application in many other members of the phylum Bacteroidetes.
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31
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Li Z, Zhang C, Wang S, Cao J, Zhang W, Lu X. A new locus in Cytophaga hutchinsonii involved in colony spreading on agar surfaces and individual cell gliding. FEMS Microbiol Lett 2015; 362:fnv095. [PMID: 26066317 DOI: 10.1093/femsle/fnv095] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 06/01/2015] [Indexed: 11/14/2022] Open
Abstract
Cytophaga hutchinsonii glides rapidly over surfaces by an unknown mechanism without flagella and type IV pili and it can degrade crystalline cellulose efficiently by a novel mechanism. Tn4351 transposon mutagenesis was used to identify a new gene, CHU_1798, essential for colony spreading on agar surfaces. Further study showed that disruption of CHU_1798 caused non-spreading colonies on both soft and hard agar surfaces and individual cells were partially deficient in gliding on glass surfaces. The CHU_1798 mutant could digest cellulose as long as the cells were in direct contact with the cellulose, but it could not degrade cellulose powder buried in the agar plate. Scanning electron microscopy showed that individual mutant cells arranged irregularly on the cellulose fiber surface at an early stage of incubation, but later showed a regular parallel arrangement when there were plenty of cells and could spread along the cellulose fibers. These results suggest that CHU_1798 plays an important role in the motility of C. hutchinsonii and provide insight into the relation between cell motility and cellulose degradation.
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Affiliation(s)
- Zhe Li
- State Key Laboratory of Microbial Technology, School of Life Science, Shandong University, Jinan 250100, China
| | - Cong Zhang
- State Key Laboratory of Microbial Technology, School of Life Science, Shandong University, Jinan 250100, China
| | - Sen Wang
- State Key Laboratory of Microbial Technology, School of Life Science, Shandong University, Jinan 250100, China
| | - Jing Cao
- State Key Laboratory of Microbial Technology, School of Life Science, Shandong University, Jinan 250100, China
| | - Weican Zhang
- State Key Laboratory of Microbial Technology, School of Life Science, Shandong University, Jinan 250100, China
| | - Xuemei Lu
- State Key Laboratory of Microbial Technology, School of Life Science, Shandong University, Jinan 250100, China
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Flavobacterium johnsoniae PorV is required for secretion of a subset of proteins targeted to the type IX secretion system. J Bacteriol 2014; 197:147-58. [PMID: 25331433 DOI: 10.1128/jb.02085-14] [Citation(s) in RCA: 60] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
Flavobacterium johnsoniae exhibits gliding motility and digests many polysaccharides, including chitin. A novel protein secretion system, the type IX secretion system (T9SS), is required for gliding and chitin utilization. The T9SS secretes the cell surface motility adhesins SprB and RemA and the chitinase ChiA. Proteins involved in secretion by the T9SS include GldK, GldL, GldM, GldN, SprA, SprE, and SprT. Porphyromonas gingivalis has orthologs for each of these that are required for secretion of gingipain protease virulence factors by its T9SS. P. gingivalis porU and porV have also been linked to T9SS-mediated secretion, and F. johnsoniae has orthologs of these. Mutations in F. johnsoniae porU and porV were constructed to determine if they function in secretion. Cells of a porV deletion mutant were deficient in chitin utilization and failed to secrete ChiA. They were also deficient in secretion of the motility adhesin RemA but retained the ability to secrete SprB. SprB is involved in gliding motility and is needed for formation of spreading colonies on agar, and the porV mutant exhibited gliding motility and formed spreading colonies. However, the porV mutant was partially deficient in attachment to glass, apparently because of the absence of RemA and other adhesins on the cell surface. The porV mutant also appeared to be deficient in secretion of numerous other proteins that have carboxy-terminal domains associated with targeting to the T9SS. PorU was not required for secretion of ChiA, RemA, or SprB, indicating that it does not play an essential role in the F. johnsoniae T9SS.
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33
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Russell AB, Wexler AG, Harding BN, Whitney JC, Bohn AJ, Goo YA, Tran BQ, Barry NA, Zheng H, Peterson SB, Chou S, Gonen T, Goodlett DR, Goodman AL, Mougous JD. A type VI secretion-related pathway in Bacteroidetes mediates interbacterial antagonism. Cell Host Microbe 2014; 16:227-236. [PMID: 25070807 DOI: 10.1016/j.chom.2014.07.007] [Citation(s) in RCA: 241] [Impact Index Per Article: 24.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2014] [Revised: 07/04/2014] [Accepted: 07/09/2014] [Indexed: 12/12/2022]
Abstract
Bacteroidetes are a phylum of Gram-negative bacteria abundant in mammalian-associated polymicrobial communities, where they impact digestion, immunity, and resistance to infection. Despite the extensive competition at high cell density that occurs in these settings, cell contact-dependent mechanisms of interbacterial antagonism, such as the type VI secretion system (T6SS), have not been defined in this group of organisms. Herein we report the bioinformatic and functional characterization of a T6SS-like pathway in diverse Bacteroidetes. Using prominent human gut commensal and soil-associated species, we demonstrate that these systems localize dynamically within the cell, export antibacterial proteins, and target competitor bacteria. The Bacteroidetes system is a distinct pathway with marked differences in gene content and high evolutionary divergence from the canonical T6S pathway. Our findings offer a potential molecular explanation for the abundance of Bacteroidetes in polymicrobial environments, the observed stability of Bacteroidetes in healthy humans, and the barrier presented by the microbiota against pathogens.
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Affiliation(s)
- Alistair B Russell
- Department of Microbiology, University of Washington, Seattle, WA 98195, USA
| | - Aaron G Wexler
- Department of Microbial Pathogenesis and Microbial Diversity Institute, Yale University School of Medicine, New Haven, CT 06536, USA
| | - Brittany N Harding
- Department of Microbiology, University of Washington, Seattle, WA 98195, USA
| | - John C Whitney
- Department of Microbiology, University of Washington, Seattle, WA 98195, USA
| | - Alan J Bohn
- Department of Microbiology, University of Washington, Seattle, WA 98195, USA
| | - Young Ah Goo
- Department of Pharmaceutical Sciences, School of Pharmacy, University of Maryland, Baltimore, MD 21201, USA
| | - Bao Q Tran
- Department of Pharmaceutical Sciences, School of Pharmacy, University of Maryland, Baltimore, MD 21201, USA
| | - Natasha A Barry
- Department of Microbial Pathogenesis and Microbial Diversity Institute, Yale University School of Medicine, New Haven, CT 06536, USA
| | - Hongjin Zheng
- Janelia Research Campus, Howard Hughes Medical Institute, Ashburn, VA 20147, USA
| | - S Brook Peterson
- Department of Microbiology, University of Washington, Seattle, WA 98195, USA
| | - Seemay Chou
- Department of Microbiology, University of Washington, Seattle, WA 98195, USA
| | - Tamir Gonen
- Janelia Research Campus, Howard Hughes Medical Institute, Ashburn, VA 20147, USA
| | - David R Goodlett
- Department of Pharmaceutical Sciences, School of Pharmacy, University of Maryland, Baltimore, MD 21201, USA
| | - Andrew L Goodman
- Department of Microbial Pathogenesis and Microbial Diversity Institute, Yale University School of Medicine, New Haven, CT 06536, USA.
| | - Joseph D Mougous
- Department of Microbiology, University of Washington, Seattle, WA 98195, USA.
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Kharade SS, McBride MJ. Flavobacterium johnsoniae chitinase ChiA is required for chitin utilization and is secreted by the type IX secretion system. J Bacteriol 2014; 196:961-70. [PMID: 24363341 PMCID: PMC3957688 DOI: 10.1128/jb.01170-13] [Citation(s) in RCA: 68] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2013] [Accepted: 12/14/2013] [Indexed: 12/15/2022] Open
Abstract
Flavobacterium johnsoniae, a member of phylum Bacteriodetes, is a gliding bacterium that digests insoluble chitin and many other polysaccharides. A novel protein secretion system, the type IX secretion system (T9SS), is required for gliding motility and for chitin utilization. Five potential chitinases were identified by genome analysis. Fjoh_4555 (ChiA), a 168.9-kDa protein with two glycoside hydrolase family 18 (GH18) domains, was targeted for analysis. Disruption of chiA by insertional mutagenesis resulted in cells that failed to digest chitin, and complementation with wild-type chiA on a plasmid restored chitin utilization. Antiserum raised against recombinant ChiA was used to detect the protein and to characterize its secretion by F. johnsoniae. ChiA was secreted in soluble form by wild-type cells but remained cell associated in strains carrying mutations in any of the T9SS genes, gldK, gldL, gldM, gldNO, sprA, sprE, and sprT. Western blot and liquid chromatography-tandem mass spectrometry (LC-MS/MS) analyses suggested that ChiA was proteolytically processed into two GH18 domain-containing proteins. Proteins secreted by T9SSs typically have conserved carboxy-terminal domains (CTDs) belonging to the TIGRFAM families TIGR04131 and TIGR04183. ChiA does not exhibit strong similarity to these sequences and instead has a novel CTD. Deletion of this CTD resulted in accumulation of ChiA inside cells. Fusion of the ChiA CTD to recombinant mCherry resulted in secretion of mCherry into the medium. The results indicate that ChiA is a soluble extracellular chitinase required for chitin utilization and that it relies on a novel CTD for secretion by the F. johnsoniae T9SS.
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Affiliation(s)
- Sampada S Kharade
- Department of Biological Sciences, University of Wisconsin-Milwaukee, Milwaukee, Wisconsin, USA
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35
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Deletion of the Cytophaga hutchinsonii type IX secretion system gene sprP results in defects in gliding motility and cellulose utilization. Appl Microbiol Biotechnol 2013; 98:763-75. [PMID: 24257839 DOI: 10.1007/s00253-013-5355-2] [Citation(s) in RCA: 45] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2013] [Revised: 10/16/2013] [Accepted: 10/21/2013] [Indexed: 10/26/2022]
Abstract
Cytophaga hutchinsonii glides rapidly over surfaces and employs a novel collection of cell-associated proteins to digest crystalline cellulose. HimarEm1 transposon mutagenesis was used to isolate a mutant with an insertion in CHU_0170 (sprP) that was partially deficient in gliding motility and was unable to digest filter paper cellulose. SprP is similar in sequence to the Porphyromonas gingivalis type IX secretion system (T9SS) protein PorP that is involved in the secretion of gingipain protease virulence factors and to the Flavobacterium johnsoniae T9SS protein SprF that is needed to deliver components of the gliding motility machinery to the cell surface. We developed an efficient method to construct targeted nonpolar mutations in C. hutchinsonii and deleted sprP. The deletion mutant was defective in gliding and failed to digest cellulose, and complementation with sprP on a plasmid restored both abilities. Sequence analysis predicted that CHU_3105 is secreted by the T9SS, and deletion of sprP resulted in decreased levels of extracellular CHU_3105. The results suggest that SprP may function in protein secretion. The T9SS may be required for motility and cellulose utilization because cell surface proteins predicted to be involved in both processes have C-terminal domains that are thought to target them to this secretion system. The efficient genetic tools now available for C. hutchinsonii should allow a detailed analysis of the cellulolytic, gliding motility, and protein secretion machineries of this common but poorly understood bacterium.
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36
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Helical flow of surface protein required for bacterial gliding motility. Proc Natl Acad Sci U S A 2013; 110:11145-50. [PMID: 23781102 DOI: 10.1073/pnas.1219753110] [Citation(s) in RCA: 98] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023] Open
Abstract
Cells of Flavobacterium johnsoniae and of many other members of the phylum Bacteroidetes exhibit rapid gliding motility over surfaces by a unique mechanism. These cells do not have flagella or pili; instead, they rely on a novel motility apparatus composed of Gld and Spr proteins. SprB, a 669-kDa cell-surface adhesin, is required for efficient gliding. SprB was visualized by electron microscopy as thin 150-nm-long filaments extending from the cell surface. Fluorescence microscopy revealed movement of SprB proteins toward the poles of the cell at ∼2 μm/s. The fluorescent signals appeared to migrate around the pole and continue at the same speed toward the opposite pole along an apparent left-handed helical closed loop. Movement of SprB, and of cells, was rapidly and reversibly blocked by the addition of carbonyl cyanide m-chlorophenylhydrazone, which dissipates the proton gradient across the cytoplasmic membrane. In a gliding cell, some of the SprB protein appeared to attach to the substratum. The cell body moved forward and rotated with respect to this point of attachment. Upon reaching the rear of the cell, the attached SprB often was released from the substratum, and apparently recirculated to the front of the cell along a helical path. The results suggest a model for Flavobacterium gliding, supported by mathematical analysis, in which adhesins such as SprB are propelled along a closed helical loop track, generating rotation and translation of the cell body.
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Flavobacterium johnsoniae GldK, GldL, GldM, and SprA are required for secretion of the cell surface gliding motility adhesins SprB and RemA. J Bacteriol 2013; 195:3201-12. [PMID: 23667240 DOI: 10.1128/jb.00333-13] [Citation(s) in RCA: 87] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Flavobacterium johnsoniae cells move rapidly over surfaces by gliding motility. Gliding results from the movement of adhesins such as SprB and RemA along the cell surface. These adhesins are delivered to the cell surface by a Bacteroidetes-specific secretion system referred to as the type IX secretion system (T9SS). GldN, SprE, SprF, and SprT are involved in secretion by this system. Here we demonstrate that GldK, GldL, GldM, and SprA are each also involved in secretion. Nonpolar deletions of gldK, gldL, or gldM resulted in the absence of gliding motility and in T9SS defects. The mutant cells produced SprB and RemA proteins but failed to secrete them to the cell surface. The mutants were resistant to phages that use SprB or RemA as a receptor, and they failed to attach to glass, presumably because of the absence of cell surface adhesins. Deletion of sprA resulted in similar but slightly less dramatic phenotypes. sprA mutant cells failed to secrete SprB and RemA, but cells remained susceptible to some phages and retained some limited ability to glide. The phenotype of the sprA mutant was similar to those previously described for sprE and sprT mutants. SprA, SprE, and SprT are needed for secretion of SprB and RemA but may not be needed for secretion of other proteins targeted to the T9SS. Genetic and molecular experiments demonstrate that gldK, gldL, gldM, and gldN form an operon and suggest that the proteins encoded by these genes may interact to form part of the F. johnsoniae T9SS.
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Kientz B, Ducret A, Luke S, Vukusic P, Mignot T, Rosenfeld E. Glitter-like iridescence within the bacteroidetes especially Cellulophaga spp.: optical properties and correlation with gliding motility. PLoS One 2012; 7:e52900. [PMID: 23300811 PMCID: PMC3531331 DOI: 10.1371/journal.pone.0052900] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2012] [Accepted: 11/23/2012] [Indexed: 11/19/2022] Open
Abstract
Iridescence results from structures that generate color. Iridescence of bacterial colonies has recently been described and illustrated. The glitter-like iridescence class, created especially for a few strains of Cellulophaga lytica, exhibits an intense iridescence under direct illumination. Such color appearance effects were previously associated with other bacteria from the Bacteroidetes phylum, but without clear elucidation and illustration. To this end, we compared various bacterial strains to which the iridescent trait was attributed. All Cellulophaga species and additional Bacteroidetes strains from marine and terrestrial environments were investigated. A selection of bacteria, mostly marine in origin, were found to be iridescent. Although a common pattern of reflected wavelengths was recorded for the species investigated, optical spectroscopy and physical measurements revealed a range of different glitter-like iridescence intensity and color profiles. Importantly, gliding motility was found to be a common feature of all iridescent colonies. Dynamic analyses of “glitter” formation at the edges of C. lytica colonies showed that iridescence was correlated with layer superposition. Both gliding motility, and unknown cell-to-cell communication processes, may be required for the establishment, in time and space, of the necessary periodic structures responsible for the iridescent appearance of Bacteroidetes.
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Affiliation(s)
- Betty Kientz
- UMR 7266 CNRS Littoral Environnement et Sociétés, University of La Rochelle, La Rochelle, France
| | - Adrien Ducret
- UMR 7283 CNRS Laboratoire de Chimie Bactérienne, Institut de Microbiologie de la Méditerranée, University of Aix-Marseille, Marseille, France
| | - Stephen Luke
- School of Physics, University of Exeter, Exeter, United Kingdom
| | - Peter Vukusic
- School of Physics, University of Exeter, Exeter, United Kingdom
| | - Tâm Mignot
- UMR 7283 CNRS Laboratoire de Chimie Bactérienne, Institut de Microbiologie de la Méditerranée, University of Aix-Marseille, Marseille, France
| | - Eric Rosenfeld
- UMR 7266 CNRS Littoral Environnement et Sociétés, University of La Rochelle, La Rochelle, France
- * E-mail:
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Flavobacterium johnsoniae RemA is a mobile cell surface lectin involved in gliding. J Bacteriol 2012; 194:3678-88. [PMID: 22582276 DOI: 10.1128/jb.00588-12] [Citation(s) in RCA: 63] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Cells of Flavobacterium johnsoniae move rapidly over surfaces by a process known as gliding motility. Gld proteins are thought to comprise the motor that propels the cell surface adhesin SprB. Cells with mutations in sprB are partially defective in motility and are also resistant to some bacteriophages. Transposon mutagenesis of a strain carrying a deletion spanning sprB identified eight mutants that were resistant to additional phages and exhibited reduced motility. Four of the mutants had transposon insertions in remA, which encodes a cell surface protein that has a lectin domain and appears to interact with polysaccharides. Three other genes identified in this screen (remC, wza, and wzc) encode proteins predicted to be involved in polysaccharide synthesis and secretion. Myc-tagged versions of RemA localized to the cell surface and were propelled rapidly along the cell at speeds of 1 to 2 μm/s. Deletion of gldN and gldO, which encode components of a bacteroidete protein secretion system, blocked the transport of RemA to the cell surface. Overexpression of RemA resulted in the formation of cell aggregates that were dispersed by the addition of galactose or rhamnose. Cells lacking RemC, Wza, and Wzc failed to aggregate. Cells of a remC mutant and cells of a remA mutant, neither of which formed aggregates in isolation, aggregated when they were mixed together, suggesting that polysaccharides secreted by one cell may interact with RemA on another cell. Fluorescently labeled lectin Ricinus communis agglutinin I detected polysaccharides secreted by F. johnsoniae. The polysaccharides bound to cells expressing RemA and were rapidly propelled on the cell surface. RemA appears to be a mobile cell surface adhesin, and secreted polysaccharides may interact with the lectin domain of RemA and enhance motility.
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Kiss H, Nett M, Domin N, Martin K, Maresca JA, Copeland A, Lapidus A, Lucas S, Berry KW, Glavina Del Rio T, Dalin E, Tice H, Pitluck S, Richardson P, Bruce D, Goodwin L, Han C, Detter JC, Schmutz J, Brettin T, Land M, Hauser L, Kyrpides NC, Ivanova N, Göker M, Woyke T, Klenk HP, Bryant DA. Complete genome sequence of the filamentous gliding predatory bacterium Herpetosiphon aurantiacus type strain (114-95(T)). Stand Genomic Sci 2011; 5:356-70. [PMID: 22675585 PMCID: PMC3368417 DOI: 10.4056/sigs.2194987] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023] Open
Abstract
Herpetosiphon aurantiacus Holt and Lewin 1968 is the type species of the genus Herpetosiphon, which in turn is the type genus of the family Herpetosiphonaceae, type family of the order Herpetosiphonales in the phylum Chloroflexi. H. aurantiacus cells are organized in filaments which can rapidly glide. The species is of interest not only because of its rather isolated position in the tree of life, but also because Herpetosiphon ssp. were identified as predators capable of facultative predation by a wolf pack strategy and of degrading the prey organisms by excreted hydrolytic enzymes. The genome of H. aurantiacus strain 114-95(T) is the first completely sequenced genome of a member of the family Herpetosiphonaceae. The 6,346,587 bp long chromosome and the two 339,639 bp and 99,204 bp long plasmids with a total of 5,577 protein-coding and 77 RNA genes was sequenced as part of the DOE Joint Genome Institute Program DOEM 2005.
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Mutations in Flavobacterium johnsoniae sprE result in defects in gliding motility and protein secretion. J Bacteriol 2011; 193:5322-7. [PMID: 21784937 DOI: 10.1128/jb.05480-11] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
Cells of the gliding bacterium Flavobacterium johnsoniae move rapidly over surfaces. Transposon mutagenesis was used to identify sprE, which is involved in gliding. Mutations in sprE resulted in the formation of nonspreading colonies on agar. sprE mutant cells in wet mounts were almost completely deficient in attachment to and movement on glass, but a small percentage of cells exhibited slight movements, indicating that the motility machinery was not completely disrupted. SprE is a predicted lipoprotein with a tetratricopeptide repeat domain. SprE is similar in sequence to Porphyromonas gingivalis PorW, which is required for secretion of gingipain protease virulence factors. Disruption of F. johnsoniae sprE resulted in decreased extracellular chitinase activity and decreased secretion of the cell surface motility protein SprB. Reduced secretion of cell surface components of the gliding machinery, such as SprB, may account for the defects in gliding. Orthologs of sprE are found in many gliding and nongliding members of the phylum Bacteroidetes, suggesting that similar protein secretion systems are common among members of this large and diverse group of bacteria.
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