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Astafyeva Y, Gurschke M, Streit WR, Krohn I. Interplay between the microalgae Micrasterias radians and its symbiont Dyadobacter sp. HH091. Front Microbiol 2022; 13:1006609. [PMID: 36312980 PMCID: PMC9606717 DOI: 10.3389/fmicb.2022.1006609] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2022] [Accepted: 09/21/2022] [Indexed: 11/13/2022] Open
Abstract
Based on previous research, related to detailed insight into mutualistic collaboration of microalga and its microbiome, we established an artificial plant-bacteria system of the microalga Micrasterias radians MZCH 672 and the bacterial isolate Dyadobacter sp. HH091. The bacteria, affiliated with the phylum Bacteroidota, strongly stimulated growth of the microalga when it was added to axenic algal cultures. For further advances, we studied the isolate HH091 and its interaction with the microalga M. radians using transcriptome and extensive genome analyses. The genome of HH091 contains predicted polysaccharide utilizing gene clusters co-working with the type IX secretion system (T9SS) and conceivably involved in the algae-bacteria liaison. Here, we focus on characterizing the mechanism of T9SS, implementing the attachment and invasion of microalga by Dyadobacter sp. HH091. Omics analysis exposed T9SS genes: gldK, gldL, gldM, gldN, sprA, sprE, sprF, sprT, porU and porV. Besides, gld genes not considered as the T9SS components but required for gliding motility and protein secretion (gldA, gldB, gldD, gldF, gldG, gldH, gldI, gldJ), were also identified at this analysis. A first model of T9SS apparatus of Dyadobacter was proposed in a course of this research. Using the combination of fluorescence labeling of Dyadobacter sp. HH091, we examined the bacterial colonisation and penetration into the cell wall of the algal host M. radians MZCH 672.
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Khare D, Chandwadkar P, Acharya C. Gliding motility of a uranium-tolerant Bacteroidetes bacterium Chryseobacterium sp. strain PMSZPI: insights into the architecture of spreading colonies. Environ Microbiol Rep 2022; 14:453-463. [PMID: 34907658 DOI: 10.1111/1758-2229.13034] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/23/2021] [Revised: 10/29/2021] [Accepted: 11/30/2021] [Indexed: 06/14/2023]
Abstract
Uranium-tolerant soil bacterium Chryseobacterium sp. strain PMSZPI moved over solid agar surfaces by gliding motility thereby forming spreading colonies which is a hallmark of members of Bacteroidetes phylum. PMSZPI genome harboured orthologs of all the gld and spr genes considered as core bacteroidetes gliding motility genes of which gldK, gldL, gldM and gldN were co-transcribed. Here, we present the intriguing interplay between gliding motility and cellular organization in PMSZPI spreading colonies. While nutrient deficiency enhanced colony spreading, high agar concentrations and presence of motility inhibitor like 5-hydroxyindole reduced the spreading. A detailed in situ structural analysis of spreading colonies revealed closely packed cells forming multiple layers at centre of colony while the edges showed clusters of cells periodically arranged in hexagonal lattices interconnected with each other. The cell migration within colony was visualized as branched structures wherein the cells were buried within extracellular matrix. PMSZPI colonies exhibited strong iridescence possibly as a result of periodicity within the cell population achieved through gliding motility. Presence of uranium reduced motility and iridescence and induced biofilm formation. The coordinated study of gliding motility and iridescence apparently influenced by uranium provides unique insights into the lifestyle of PMSZPI residing in uranium enriched environment.
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Affiliation(s)
- Devanshi Khare
- Molecular Biology Division, Bhabha Atomic Research Centre, Trombay, Mumbai, 400085, India
- Homi Bhabha National Institute, Anushakti Nagar, Mumbai, 400094, India
| | - Pallavi Chandwadkar
- Molecular Biology Division, Bhabha Atomic Research Centre, Trombay, Mumbai, 400085, India
| | - Celin Acharya
- Molecular Biology Division, Bhabha Atomic Research Centre, Trombay, Mumbai, 400085, India
- Homi Bhabha National Institute, Anushakti Nagar, Mumbai, 400094, India
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3
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Abstract
The Fo ATP synthase, the bacterial flagellar motor, and the bacterial type 9 secretion system (T9SS) are the three known proton motive force driven biological rotary motors. In this review, we summarize the current information on the nuts and bolts of T9SS. Torque generation by T9SS, its role in gliding motility of bacteria, and the mechanism via which a T9SS-driven swarm shapes the microbiota are discussed. The knowledge gaps in our current understanding of the T9SS machinery are outlined.
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Affiliation(s)
- Abhishek Trivedi
- School of Life Sciences, Arizona State University, Tempe, AZ, United States
- Biodesign Center for Fundamental and Applied Microbiomics, Arizona State University, Tempe, AZ, United States
- Center for Biological Physics, Arizona State University, Tempe, AZ, United States
| | - Jitendrapuri Gosai
- School of Life Sciences, Arizona State University, Tempe, AZ, United States
- Biodesign Center for Fundamental and Applied Microbiomics, Arizona State University, Tempe, AZ, United States
- Center for Biological Physics, Arizona State University, Tempe, AZ, United States
| | - Daisuke Nakane
- Department of Engineering Science, The University of Electro-Communications, Tokyo, Japan
| | - Abhishek Shrivastava
- School of Life Sciences, Arizona State University, Tempe, AZ, United States
- Biodesign Center for Fundamental and Applied Microbiomics, Arizona State University, Tempe, AZ, United States
- Center for Biological Physics, Arizona State University, Tempe, AZ, United States
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4
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Li C, Hurley A, Hu W, Warrick JW, Lozano GL, Ayuso JM, Pan W, Handelsman J, Beebe DJ. Social motility of biofilm-like microcolonies in a gliding bacterium. Nat Commun 2021; 12:5700. [PMID: 34588437 PMCID: PMC8481357 DOI: 10.1038/s41467-021-25408-7] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2020] [Accepted: 07/09/2021] [Indexed: 11/27/2022] Open
Abstract
Bacterial biofilms are aggregates of surface-associated cells embedded in an extracellular polysaccharide (EPS) matrix, and are typically stationary. Studies of bacterial collective movement have largely focused on swarming motility mediated by flagella or pili, in the absence of a biofilm. Here, we describe a unique mode of collective movement by a self-propelled, surface-associated biofilm-like multicellular structure. Flavobacterium johnsoniae cells, which move by gliding motility, self-assemble into spherical microcolonies with EPS cores when observed by an under-oil open microfluidic system. Small microcolonies merge, creating larger ones. Microscopic analysis and computer simulation indicate that microcolonies move by cells at the base of the structure, attached to the surface by one pole of the cell. Biochemical and mutant analyses show that an active process drives microcolony self-assembly and motility, which depend on the bacterial gliding apparatus. We hypothesize that this mode of collective bacterial movement on solid surfaces may play potential roles in biofilm dynamics, bacterial cargo transport, or microbial adaptation. However, whether this collective motility occurs on plant roots or soil particles, the native environment for F. johnsoniae, is unknown. Bacterial biofilms are aggregates of surface-associated cells embedded in an extracellular polysaccharide (EPS) matrix. Here, the authors describe a unique mode of collective movement by self-propelled, surface-associated spherical microcolonies with EPS cores in the gliding bacterium Flavobacterium johnsoniae.
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Affiliation(s)
- Chao Li
- Carbone Cancer Center, University of Wisconsin-Madison, Madison, WI, USA
| | - Amanda Hurley
- Wisconsin Institute for Discovery, University of Wisconsin-Madison, Madison, WI, USA.,Department of Plant Pathology, University of Wisconsin-Madison, Madison, WI, USA
| | - Wei Hu
- Department of Mechanical Engineering, University of Wisconsin-Madison, Madison, WI, USA
| | - Jay W Warrick
- Department of Biomedical Engineering, University of Wisconsin-Madison, Madison, WI, USA
| | - Gabriel L Lozano
- Wisconsin Institute for Discovery, University of Wisconsin-Madison, Madison, WI, USA.,Divisions of Infectious Diseases and Gastroenterology, Boston Children's Hospital and Harvard Medical School, Boston, MA, USA
| | - Jose M Ayuso
- Carbone Cancer Center, University of Wisconsin-Madison, Madison, WI, USA.,Department of Biomedical Engineering, University of Wisconsin-Madison, Madison, WI, USA.,Morgridge Institute for Research, Madison, WI, USA
| | - Wenxiao Pan
- Department of Mechanical Engineering, University of Wisconsin-Madison, Madison, WI, USA
| | - Jo Handelsman
- Wisconsin Institute for Discovery, University of Wisconsin-Madison, Madison, WI, USA.,Department of Plant Pathology, University of Wisconsin-Madison, Madison, WI, USA
| | - David J Beebe
- Carbone Cancer Center, University of Wisconsin-Madison, Madison, WI, USA. .,Department of Biomedical Engineering, University of Wisconsin-Madison, Madison, WI, USA. .,Department of Pathology and Laboratory Medicine, University of Wisconsin-Madison, Madison, WI, USA.
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5
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Eckroat TJ, Greguske C, Hunnicutt DW. The Type 9 Secretion System Is Required for Flavobacterium johnsoniae Biofilm Formation. Front Microbiol 2021; 12:660887. [PMID: 34539591 PMCID: PMC8444969 DOI: 10.3389/fmicb.2021.660887] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2021] [Accepted: 08/06/2021] [Indexed: 12/03/2022] Open
Abstract
Flavobacterium johnsoniae forms biofilms in low nutrient conditions. Protein secretion and cell motility may have roles in biofilm formation. The F. johnsoniae type IX secretion system (T9SS) is important for both secretion and motility. To determine the roles of each process in biofilm formation, mutants defective in secretion, in motility, or in both processes were tested for their effects on biofilm production using a crystal violet microplate assay. All mutants that lacked both motility and T9SS-mediated secretion failed to produce biofilms. A porV deletion mutant, which was severely defective for secretion, but was competent for motility, also produced negligible biofilm. In contrast, mutants that retained secretion but had defects in gliding formed biofilms. An sprB mutant that is severely but incompletely defective in gliding motility but retains a fully functional T9SS was similar to the wild type in biofilm formation. Mutants with truncations of the gldJ gene that compromise motility but not secretion showed partial reduction in biofilm formation compared to wild type. Unlike the sprB mutant, these gldJ truncation mutants were essentially nonmotile. The results show that a functional T9SS is required for biofilm formation. Gliding motility, while not required for biofilm formation, also appears to contribute to formation of a robust biofilm.
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Affiliation(s)
- Todd J. Eckroat
- School of Science, Penn State Erie, The Behrend College, Erie, PA, United States
| | - Camillus Greguske
- Division of Natural Science, St. Norbert College, De Pere, WI, United States
| | - David W. Hunnicutt
- Division of Natural Science, St. Norbert College, De Pere, WI, United States
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Lorencik K, Ekiert R, Zhu Y, McBride MJ, Gennis RB, Sarewicz M, Osyczka A. 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 DOI: 10.1128/Spectrum.00135-21] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [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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Kraut-Cohen J, Shapiro OH, Dror B, Cytryn E. Pectin Induced Colony Expansion of Soil-Derived Flavobacterium Strains. Front Microbiol 2021; 12:651891. [PMID: 33889143 PMCID: PMC8056085 DOI: 10.3389/fmicb.2021.651891] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2021] [Accepted: 02/22/2021] [Indexed: 11/20/2022] Open
Abstract
The genus Flavobacterium is characterized by the capacity to metabolize complex organic compounds and a unique gliding motility mechanism. Flavobacteria are often abundant in root microbiomes of various plants, but the factors contributing to this high abundance are currently unknown. In this study, we evaluated the effect of various plant-associated poly- and mono-saccharides on colony expansion of two Flavobacterium strains. Both strains were able to spread on pectin and other polysaccharides such as microcrystalline cellulose. However, only pectin (but not pectin monomers), a component of plant cell walls, enhanced colony expansion on solid surfaces in a dose- and substrate-dependent manner. On pectin, flavobacteria exhibited bi-phasic motility, with an initial phase of rapid expansion, followed by growth within the colonized area. Proteomic and gene expression analyses revealed significant induction of carbohydrate metabolism related proteins when flavobacteria were grown on pectin, including selected SusC/D, TonB-dependent glycan transport operons. Our results show a positive correlation between colony expansion and the upregulation of proteins involved in sugar uptake, suggesting an unknown linkage between specific operons encoding for glycan uptake and metabolism and flavobacterial expansion. Furthermore, within the context of flavobacterial-plant interactions, they suggest that pectin may facilitate flavobacterial expansion on plant surfaces in addition to serving as an essential carbon source.
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Affiliation(s)
- Judith Kraut-Cohen
- Institute of Soil, Water and Environmental Sciences, Agricultural Research Organization, Volcani Center, Rishon LeZion, Israel
| | - Orr H Shapiro
- Institute of Postharvest and Food Sciences, Agricultural Research Organization, Volcani Center, Rishon LeZion, Israel
| | - Barak Dror
- Institute of Soil, Water and Environmental Sciences, Agricultural Research Organization, Volcani Center, Rishon LeZion, Israel.,Department of Plant Pathology and Microbiology, The R.H. Smith Faculty of Agriculture, Food and Environment, The Hebrew University of Jerusalem, Rehovot, Israel
| | - Eddie Cytryn
- Institute of Soil, Water and Environmental Sciences, Agricultural Research Organization, Volcani Center, Rishon LeZion, Israel
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8
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Nau GJ, Horzempa J, O’Dee D, Brown MJ, Russo BC, Hernandez A, Dillon ST, Cheng J, Kane LP, Sanker S, Hukriede NA. A predicted Francisella tularensis DXD-motif glycosyltransferase blocks immune activation. Virulence 2019; 10:643-656. [PMID: 31314675 PMCID: PMC6650193 DOI: 10.1080/21505594.2019.1631662] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2019] [Accepted: 06/07/2019] [Indexed: 02/04/2023] Open
Abstract
Pathogens enhance their survival during infections by manipulating host defenses. Francisella tularensis evades innate immune responses, which we have found to be dependent on an understudied gene ybeX (FTL_0883/FTT_0615c). To understand the function of YbeX, we sought protein interactors in F. tularensis subsp. holarctica live vaccine strain (LVS). An unstudied Francisella protein co-immunoprecipitated with recombinant YbeX, which is a predicted glycosyltransferase with a DXD-motif. There are up to four genomic copies of this gene with identical sequence in strains of F. tularensis pathogenic to humans, despite ongoing genome decay. Disruption mutations were generated by intron insertion into all three copies of this glycosyltransferase domain containing gene in LVS, gdcA1-3. The resulting strains stimulated more cytokines from macrophages in vitro than wild-type LVS and were attenuated in two in vivo infection models. GdcA was released from LVS during culture and was sufficient to block NF-κB activation when expressed in eukaryotic cells. When co-expressed in zebrafish, GdcA and YbeX were synergistically lethal to embryo development. Glycosyltransferases with DXD-motifs are found in a variety of pathogens including NleB, an Escherichia coli type-III secretion system effector that inhibits NF-κB by antagonizing death receptor signaling. To our knowledge, GdcA is the first DXD-motif glycosyltransferase that inhibits NF-κB in immune cells. Together, these findings suggest DXD-motif glycosyltransferases may be a conserved virulence mechanism used by pathogenic bacteria to remodel host defenses.
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Affiliation(s)
- Gerard J. Nau
- Division of Infectious Diseases, Alpert Medical School of Brown University, Providence, RI, USA
| | - Joseph Horzempa
- Department of Natural Sciences and Mathematics, West Liberty University, West Liberty, WV, USA
| | - Dawn O’Dee
- Department of Microbiology and Molecular Genetics, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
| | - Matthew J. Brown
- Department of Microbiology and Molecular Genetics, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
| | - Brian C. Russo
- Department of Microbiology and Molecular Genetics, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
| | - Ana Hernandez
- Division of Infectious Diseases, Alpert Medical School of Brown University, Providence, RI, USA
| | - Simon T. Dillon
- Beth Israel Deaconess Medical Center Genomics, Proteomics, and Systems Biology Center, Harvard Medical School, Boston, MA, USA
| | - Jing Cheng
- Department of Immunology, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
| | - Lawrence P. Kane
- Department of Immunology, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
| | - Subramaniam Sanker
- Department of Developmental Biology, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
| | - Neil A. Hukriede
- Department of Developmental Biology, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
- Center for Critical Care Nephrology, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
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9
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Chen Z, Wang X, Ren X, Han W, Malhi KK, Ding C, Yu S. Riemerella anatipestifer GldM is required for bacterial gliding motility, protein secretion, and virulence. Vet Res 2019; 50:43. [PMID: 31164171 PMCID: PMC6549377 DOI: 10.1186/s13567-019-0660-0] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2018] [Accepted: 04/12/2019] [Indexed: 12/02/2022] Open
Abstract
Riemerella anatipestifer is a major pathogenic agent of duck septicemic and exudative diseases. Genetic analyses suggest that this pathogen has a novel protein secretion system, known as the “type IX secretion system” (T9SS). We previously reported that deletion of the AS87_RS08465 gene significantly reduced the bacterial virulence of the R. anatipestifer strain Yb2, but the mechanism remained unclear. The AS87_RS08465 gene is predicted to encode the gliding motility protein GldM (GldM) protein, a key component of the T9SS complex. In this study, Western blotting analysis demonstrated that R. anatipestifer GldM was localized to the cytomembrane. Further study revealed that the adhesion and invasion capacities of the mutant strain RA2281 (designated Yb2ΔgldM) in Vero cells and the bacterial loads in the blood of infected ducks were significantly reduced. RNA-Seq and PCR analyses showed that six genes were upregulated and five genes were downregulated in the mutant strain Yb2ΔgldM and that these genes were mainly involved in the secretion of proteins. Yb2ΔgldM was also found to be defective in gliding motility and protein secretion. Liquid chromatography–tandem mass spectrometry analysis revealed that nine of the proteins had a conserved T9SS C-terminal domain and were differentially secreted by Yb2ΔgldM compared to Yb2. The complementation strain cYb2ΔgldM recovered the adhesion and invasion capacities in Vero cells and the bacterial loads in the blood of infected ducks as well as the bacterial gliding motility and most protein secretion in the mutant strain Yb2ΔgldM to the levels of the wild-type strain Yb2. Taken together, these results indicate that R. anatipestifer GldM is associated with T9SS and is important in bacterial virulence.
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Affiliation(s)
- Zongchao Chen
- Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences (CAAS), Shanghai, China
| | - Xiaolan Wang
- Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences (CAAS), Shanghai, China
| | - Xiaomei Ren
- Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences (CAAS), Shanghai, China
| | - Wenlong Han
- Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences (CAAS), Shanghai, China
| | - Kanwar Kumar Malhi
- Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences (CAAS), Shanghai, China
| | - Chan Ding
- Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences (CAAS), Shanghai, China
| | - Shengqing Yu
- Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences (CAAS), Shanghai, China. .,Jiangsu Agri-animal Husbandry Vocational College, Veterinary Bio-pharmaceutical, Jiangsu Key Laboratory for High-Tech Research and Development of Veterinary Biopharmaceuticals, Taizhou, Jiangsu, China.
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10
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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] [What about the content of this article? (0)] [Affiliation(s)] [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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11
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Penttinen R, Hoikkala V, Sundberg LR. Gliding Motility and Expression of Motility-Related Genes in Spreading and Non-spreading Colonies of Flavobacterium columnare. Front Microbiol 2018; 9:525. [PMID: 29632520 PMCID: PMC5879114 DOI: 10.3389/fmicb.2018.00525] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2017] [Accepted: 03/08/2018] [Indexed: 11/13/2022] Open
Abstract
Gliding motility facilitates the movement of bacteria along surfaces in many Bacteroidetes species and results in spreading colonies. The adhesins required for the gliding are secreted through a gliding motility-associated protein secretion system, known as the type IX secretion system (T9SS). The fish pathogen Flavobacterium columnare produces spreading (rhizoid [Rz], soft [S]) and non-spreading (rough [R]) colony types, of which only the spreading Rz type is virulent. In this study, we explored the spreading behavior of these colony types by microscopic imaging and measured the expression of genes associated with gliding motility and T9SS (gldG, gldH, gldL, sprA, sprB, sprE, sprF, sprT, and porV) under high and low resource levels by using RT-qPCR (reverse transcription quantitative PCR). The spreading colony types responded to the low resource level with increased colony size. The non-spreading colony type, as well as the cells growing under high nutrient level expressed only moderate cell movements. Yet, a low nutrient level provoked more active gliding motility in individual cells and increased spreading by cooperative gliding. The gene expression survey demonstrated an increased expression level of sprA (a core component of T9SS) and sprF (needed for adhesin secretion) under low nutrient conditions. Surprisingly, the expression of gliding motility genes was not consistently associated with more active spreading behavior. Furthermore, no genetic differences were found between spreading and non-spreading colony types in the studied genes associated with gliding motility. Our study demonstrates that environmental nutrient level is an important regulator of both gliding motility and the expression of some of the associated genes. These results may help to understand the connections between nutrient concentration, gliding motility, and virulence of F. columnare.
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Affiliation(s)
- Reetta Penttinen
- Centre of Excellence in Biological Interactions, Department of Biological and Environmental Science and Nanoscience Center, University of Jyväskylä, Jyväskylä, Finland
| | - Ville Hoikkala
- Centre of Excellence in Biological Interactions, Department of Biological and Environmental Science and Nanoscience Center, University of Jyväskylä, Jyväskylä, Finland
| | - Lotta-Riina Sundberg
- Centre of Excellence in Biological Interactions, Department of Biological and Environmental Science and Nanoscience Center, University of Jyväskylä, Jyväskylä, Finland
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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] [What about the content of this article? (0)] [Affiliation(s)] [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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Chen S, Blom J, Loch TP, Faisal M, Walker ED. The Emerging Fish Pathogen Flavobacterium spartansii Isolated from Chinook Salmon: Comparative Genome Analysis and Molecular Manipulation. Front Microbiol 2017; 8:2339. [PMID: 29250046 PMCID: PMC5714932 DOI: 10.3389/fmicb.2017.02339] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2017] [Accepted: 11/13/2017] [Indexed: 01/29/2023] Open
Abstract
Flavobacterium spartansii strain T16T was isolated from a disease outbreak in hatchery-reared Chinook salmon (Oncorhynchus tshawytscha) fingerlings. To gain insight into its genomic content, structure and virulence pathogenesis factors, comparative genome analyses were performed using genomes from environmental and virulent Flavobacterium strains. F. spartansii shared low average nucleotide identity (ANI) to well-known fish-pathogenic flavobacteria (e.g., F. columnare, F. psychrophilum, and F. branchiophilum), indicating that it is a new and emerging fish pathogen. The genome in T16T had a length of 5,359,952 bp, a GC-content 35.7%, and 4,422 predicted protein-coding sequences. Flavobacterium core genome analysis showed that the number of shared genes decreased with the addition of input genomes and converged at 1182 genes. At least 8 genomic islands and 5 prophages were predicted in T16T. At least 133 virulence factors associated with virulence in pathogenic bacteria were highly conserved in F. spartansii T16T. Furthermore, genes linked to virulence in other bacterial species (e.g., those encoding for a type IX secretion system, collagenase and hemolysin) were found in the genome of F. spartansii T16T and were conserved in most of the analyzed pathogenic Flavobacterium. F. spartansii was resistant to ampicillin and penicillin, consistent with the presence of multiple genes encoding diverse lactamases and the penicillin-binding protein in the genome. To allow for future investigations into F. spartansii virulence in vivo, a transposon-based random mutagenesis strategy was attempted in F. spartansii T16T using pHimarEm1. Four putative gliding motility deficient mutants were obtained and the insertion sites of pHimarEm1 in the genome of these mutants were characterized. In total, study results clarify some of the mechanisms by which emerging flavobacterial fish pathogens may cause disease and also provide direly needed tools to investigate their pathogenesis.
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Affiliation(s)
- Shicheng Chen
- Department of Microbiology and Molecular Genetics, Michigan State University, East Lansing, MI, United States
| | - Jochen Blom
- Bioinformatics and Systems Biology, Justus-Liebig-University, Giessen, Germany
| | - Thomas P Loch
- Department of Pathobiology and Diagnostic Investigation, College of Veterinary Medicine, Michigan State University, East Lansing, MI, United States
| | - Mohamed Faisal
- Department of Pathobiology and Diagnostic Investigation, College of Veterinary Medicine, Michigan State University, East Lansing, MI, United States.,Department of Fisheries and Wildlife, College of Agriculture and Natural Resources, Michigan State University, East Lansing, MI, United States
| | - Edward D Walker
- Department of Microbiology and Molecular Genetics, Michigan State University, East Lansing, MI, United States
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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] [What about the content of this article? (0)] [Affiliation(s)] [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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Tekedar HC, Karsi A, Reddy JS, Nho SW, Kalindamar S, Lawrence ML. Comparative Genomics and Transcriptional Analysis of Flavobacterium columnare Strain ATCC 49512. Front Microbiol 2017; 8:588. [PMID: 28469601 PMCID: PMC5395568 DOI: 10.3389/fmicb.2017.00588] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2017] [Accepted: 03/21/2017] [Indexed: 12/28/2022] Open
Abstract
Flavobacterium columnare is a Gram-negative fish pathogen causing columnaris disease in wild and cultured fish species. Although the pathogen is widespread in aquatic environments and fish worldwide, little is known about biology of F. columnare and mechanisms of columnaris disease pathogenesis. Previously we presented the complete genome sequence of F. columnare strain ATCC 49512. Here we present a comparison of the strain ATCC 49512 genome to four other Flavobacterium genomes. In this analysis, we identified predicted proteins whose functions indicate F. columnare is capable of denitrification, which would enable anaerobic growth in aquatic pond sediments. Anaerobic growth of F. columnare ATCC 49512 with nitrate supplementation was detected experimentally. F. columnare ATCC 49512 had a relatively high number of insertion sequences and genomic islands compared to the other Flavobacterium species, suggesting a larger degree of horizontal gene exchange and genome plasticity. A type VI subtype III secretion system was encoded in F. columnare along with F. johnsoniae and F. branchiophilum. RNA sequencing proved to be a valuable technique to improve annotation quality; 41 novel protein coding regions were identified, 16 of which had a non-traditional start site (TTG, GTG, and CTT). Candidate small noncoding RNAs were also identified. Our results improve our understanding of F. columnare ATCC 49512 biology, and our results support the use of RNA sequencing to improve annotation of bacterial genomes, particularly for type strains.
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Affiliation(s)
- Hasan C Tekedar
- College of Veterinary Medicine, Mississippi State UniversityMississippi State, MS, USA
| | - Attila Karsi
- College of Veterinary Medicine, Mississippi State UniversityMississippi State, MS, USA
| | - Joseph S Reddy
- Mayo Clinic, Department of Health Sciences ResearchJacksonville, FL, USA
| | - Seong W Nho
- College of Veterinary Medicine, Mississippi State UniversityMississippi State, MS, USA
| | - Safak Kalindamar
- College of Veterinary Medicine, Mississippi State UniversityMississippi State, MS, USA
| | - Mark L Lawrence
- College of Veterinary Medicine, Mississippi State UniversityMississippi State, MS, USA
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16
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Zhu Y, McBride MJ. Comparative Analysis of Cellulophaga algicola and Flavobacterium johnsoniae Gliding Motility. J Bacteriol 2016; 198:1743-54. [PMID: 27044627 DOI: 10.1128/JB.01020-15] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [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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Plant KP, LaPatra SE, Call DR, Cain KD. Attempts at validating a recombinant Flavobacterium psychrophilum gliding motility protein N as a vaccine candidate in rainbow trout, Oncorhynchus mykiss (Walbaum) against bacterial cold-water disease. FEMS Microbiol Lett 2014; 358:14-20. [PMID: 25053267 DOI: 10.1111/1574-6968.12543] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2014] [Revised: 07/10/2014] [Accepted: 07/16/2014] [Indexed: 11/29/2022] Open
Abstract
The Flavobacterium psychrophilum gliding motility N (GldN) protein was investigated to determine its ability to elicit antibody responses and provide protective immunity in rainbow trout Oncorhynchus mykiss (Walbaum). GldN was PCR-amplified, cloned into pET102/D-TOPO, and expressed in Escherichia coli. Bacteria expressing recombinant GldN (rGldN) were formalin-inactivated and injected intraperitoneally (i.p.) into rainbow trout with Freund's complete adjuvant (FCA) in four separate studies that used two different immunization protocols followed by challenge evaluations. Fish injected with E. coli only in FCA served as the control. Antibody responses to F. psychrophilum whole-cell lysates measured by ELISA were low in all four studies. Protection against F. psychrophilum challenge was observed in the first study, but not in the three following studies. The discrepancies in results obtained in the later studies are unclear but may relate to formalin treatment of the antigen preparations. Overall, it appeared that rGldN delivered i.p. as a crude formalin-killed preparation is not a consistent vaccine candidate, and more work is required. Additionally, this study illustrates the importance of conducting multiple in vivo evaluations on potential vaccine(s) before any conclusions are drawn.
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Affiliation(s)
- Karen P Plant
- Hagerman Fish Culture Experiment Station, University of Idaho, Hagerman, ID, USA
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18
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Rhodes RG, Samarasam MN, Van Groll EJ, McBride MJ. 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] [What about the content of this article? (0)] [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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Shelswell KJ, Beatty JT. Coordinated, long-range, solid substrate movement of the purple photosynthetic bacterium Rhodobacter capsulatus. PLoS One 2011; 6:e19646. [PMID: 21573194 PMCID: PMC3087807 DOI: 10.1371/journal.pone.0019646] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2010] [Accepted: 04/11/2011] [Indexed: 11/19/2022] Open
Abstract
The long-range movement of Rhodobacter capsulatus cells in the glass-agar interstitial region of borosilicate Petri plates was found to be due to a subset of the cells inoculated into plates. The macroscopic appearance of plates indicated that a small group of cells moved in a coordinated manner to form a visible satellite cluster of cells. Satellite clusters were initially separated from the point of inoculation by the absence of visible cell density, but after 20 to 24 hours this space was colonized by cells apparently shed from a group of cells moving away from the point of inoculation. Cell movements consisted of flagellum-independent and flagellum-dependent motility contributions. Flagellum-independent movement occurred at an early stage, such that satellite clusters formed after 12 to 24 hours. Subsequently, after 24 to 32 hours, a flagellum-dependent dispersal of cells became visible, extending laterally outward from a line of flagellum-independent motility. These modes of taxis were found in several environmental isolates and in a variety of mutants, including a strain deficient in the production of the R. capsulatus acyl-homoserine lactone quorum-sensing signal. Although there was great variability in the direction of movement in illuminated plates, cells were predisposed to move toward broad spectrum white light. This predisposition was increased by the use of square plates, and a statistical analysis indicated that R. capsulatus is capable of genuine phototaxis. Therefore, the variability in the direction of cell movement was attributed to optical effects on light waves passing through the plate material and agar medium.
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Affiliation(s)
- Kristopher John Shelswell
- Department of Microbiology and Immunology, University of British Columbia, Vancouver, British Columbia, Canada
| | - J. Thomas Beatty
- Department of Microbiology and Immunology, University of British Columbia, Vancouver, British Columbia, Canada
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Rhodes RG, Pucker HG, McBride MJ. Development and use of a gene deletion strategy for Flavobacterium johnsoniae to identify the redundant gliding motility genes remF, remG, remH, and remI. J Bacteriol 2011; 193:2418-28. [PMID: 21421754 DOI: 10.1128/JB.00117-11] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Cells of Flavobacterium johnsoniae exhibit rapid gliding motility over surfaces. Cell movement is thought to involve motor complexes comprised of Gld proteins that propel the cell surface adhesin SprB. The four distal genes of the sprB operon (sprC, sprD, sprB, and sprF) are required for normal motility and for formation of spreading colonies, but the roles of the remaining three genes (remF, remG, and fjoh_0982) are unclear. A gene deletion strategy was developed to determine whether these genes are involved in gliding. A spontaneous streptomycin-resistant rpsL mutant of F. johnsoniae was isolated. Introduction of wild-type rpsL on a plasmid restored streptomycin sensitivity, demonstrating that wild-type rpsL is dominant to the mutant allele. The gene deletion strategy employed a suicide vector carrying wild-type rpsL and used streptomycin for counterselection. This approach was used to delete the region spanning remF, remG, and fjoh_0982. The mutant cells formed spreading colonies, demonstrating that these genes are not required for normal motility. Analysis of the genome revealed a paralog of remF (remH) and a paralog of remG (remI). Deletion of remH and remI had no effect on motility of wild-type cells, but cells lacking remF and remH, or cells lacking remG and remI, formed nonspreading colonies. The motility defects resulting from the combination of mutations suggest that the paralogous proteins perform redundant functions in motility. The rpsL counterselection strategy allows construction of unmarked mutations to determine the functions of individual motility proteins or to analyze other aspects of F. johnsoniae physiology.
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Rhodes RG, Nelson SS, Pochiraju S, McBride MJ. Flavobacterium johnsoniae sprB is part of an operon spanning the additional gliding motility genes sprC, sprD, and sprF. J Bacteriol 2011; 193:599-610. [PMID: 21131497 DOI: 10.1128/JB.01203-10] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [What about the content of this article? (0)] [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 gliding motor that propels cell surface adhesins, such as the 669-kDa SprB. A novel protein secretion apparatus called the Por secretion system (PorSS) is required for assembly of SprB on the cell surface. Genetic and molecular analyses revealed that sprB is part of a seven-gene operon spanning 29.3 kbp of DNA. In addition to sprB, three other genes of this operon (sprC, sprD, and sprF) are involved in gliding. Mutations in sprB, sprC, sprD, and sprF resulted in cells that failed to form spreading colonies on agar but that exhibited some motility on glass in wet mounts. SprF exhibits some similarity to Porphyromonas gingivalis PorP, which is required for secretion of gingipain protease virulence factors via the P. gingivalis PorSS. F. johnsoniae sprF mutants produced SprB protein but were defective in localization of SprB to the cell surface, suggesting a role for SprF in secretion of SprB. The F. johnsoniae PorSS is involved in secretion of extracellular chitinase in addition to its role in secretion of SprB. SprF was not needed for chitinase secretion and may be specifically required for SprB secretion by the PorSS. Cells with nonpolar mutations in sprC or sprD produced and secreted SprB and propelled it rapidly along the cell surface. Multiple paralogs of sprB, sprC, sprD, and sprF are present in the genome, which may explain why mutations in sprB, sprC, sprD, and sprF do not result in complete loss of motility and suggests the possibility that semiredundant SprB-like adhesins may allow movement of cells over different surfaces.
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Klesius PH, Pridgeon JW, Aksoy M. Chemotactic factors of Flavobacterium columnare to skin mucus of healthy channel catfish (Ictalurus punctatus). FEMS Microbiol Lett 2010; 310:145-51. [DOI: 10.1111/j.1574-6968.2010.02060.x] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
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Rhodes RG, Samarasam MN, Shrivastava A, van Baaren JM, Pochiraju S, Bollampalli S, McBride MJ. Flavobacterium johnsoniae gldN and gldO are partially redundant genes required for gliding motility and surface localization of SprB. J Bacteriol 2010; 192:1201-11. [PMID: 20038590 DOI: 10.1128/JB.01495-09] [Citation(s) in RCA: 57] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Cells of the gliding bacterium Flavobacterium johnsoniae move rapidly over surfaces. Mutations in gldN cause a partial defect in gliding. A novel bacteriophage selection strategy was used to aid construction of a strain with a deletion spanning gldN and the closely related gene gldO in an otherwise wild-type F. johnsoniae UW101 background. Bacteriophage transduction was used to move a gldN mutation into F. johnsoniae UW101 to allow phenotypic comparison with the gldNO deletion mutant. Cells of the gldN mutant formed nonspreading colonies on agar but retained some ability to glide in wet mounts. In contrast, cells of the gldNO deletion mutant were completely nonmotile, indicating that cells require GldN, or the GldN-like protein GldO, to glide. Recent results suggest that Porphyromonas gingivalis PorN, which is similar in sequence to GldN, has a role in protein secretion across the outer membrane. Cells of the F. johnsoniae gldNO deletion mutant were defective in localization of the motility protein SprB to the cell surface, suggesting that GldN may be involved in secretion of components of the motility machinery. Cells of the gldNO deletion mutant were also deficient in chitin utilization and were resistant to infection by bacteriophages, phenotypes that may also be related to defects in protein secretion.
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McBride MJ, Xie G, Martens EC, Lapidus A, Henrissat B, Rhodes RG, Goltsman E, Wang W, Xu J, Hunnicutt DW, Staroscik AM, Hoover TR, Cheng YQ, Stein JL. Novel features of the polysaccharide-digesting gliding bacterium Flavobacterium johnsoniae as revealed by genome sequence analysis. Appl Environ Microbiol 2009; 75:6864-75. [PMID: 19717629 DOI: 10.1128/AEM.01495-09] [Citation(s) in RCA: 184] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023] Open
Abstract
The 6.10-Mb genome sequence of the aerobic chitin-digesting gliding bacterium Flavobacterium johnsoniae (phylum Bacteroidetes) is presented. F. johnsoniae is a model organism for studies of bacteroidete gliding motility, gene regulation, and biochemistry. The mechanism of F. johnsoniae gliding is novel, and genome analysis confirms that it does not involve well-studied motility organelles, such as flagella or type IV pili. The motility machinery is composed of Gld proteins in the cell envelope that are thought to comprise the "motor" and SprB, which is thought to function as a cell surface adhesin that is propelled by the motor. Analysis of the genome identified genes related to sprB that may encode alternative adhesins used for movement over different surfaces. Comparative genome analysis revealed that some of the gld and spr genes are found in nongliding bacteroidetes and may encode components of a novel protein secretion system. F. johnsoniae digests proteins, and 125 predicted peptidases were identified. F. johnsoniae also digests numerous polysaccharides, and 138 glycoside hydrolases, 9 polysaccharide lyases, and 17 carbohydrate esterases were predicted. The unexpected ability of F. johnsoniae to digest hemicelluloses, such as xylans, mannans, and xyloglucans, was predicted based on the genome analysis and confirmed experimentally. Numerous predicted cell surface proteins related to Bacteroides thetaiotaomicron SusC and SusD, which are likely involved in binding of oligosaccharides and transport across the outer membrane, were also identified. Genes required for synthesis of the novel outer membrane flexirubin pigments were identified by a combination of genome analysis and genetic experiments. Genes predicted to encode components of a multienzyme nonribosomal peptide synthetase were identified, as were novel aspects of gene regulation. The availability of techniques for genetic manipulation allows rapid exploration of the features identified for the polysaccharide-digesting gliding bacteroidete F. johnsoniae.
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Kunttu HMT, Suomalainen LR, Jokinen EI, Valtonen ET. Flavobacterium columnare colony types: connection to adhesion and virulence? Microb Pathog 2008; 46:21-7. [PMID: 18984035 DOI: 10.1016/j.micpath.2008.10.001] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2008] [Revised: 09/03/2008] [Accepted: 10/04/2008] [Indexed: 11/26/2022]
Abstract
Four different colony morphologies were produced by Flavobacterium columnare strains on Shieh agar plate cultures: rhizoid and flat (type 1), non-rhizoid and hard (type 2), round and soft (type 3), and irregularly shaped and soft (type 4). Colonies produced on AO agar differed from these to some extent. The colony types formed on Shieh agar were studied according to molecular characteristics [Amplified Fragment Length Polymorphism (AFLP), Automated Ribosomal Intergenic Spacer Analysis (ARISA), and whole cell protein SDS-PAGE profiles], virulence on rainbow trout fingerlings, and adhesion on polystyrene and fish gills. There were no molecular differences between colony types within one strain. Type 2 was the most adherent on polystyrene, but type 1 was the most virulent. Adhesion of F. columnare strains used in this study was not connected to virulence. From fish infected with colony type 1, three colony types (types 1, 2 and 4) were isolated. Contrary to previous studies, our results suggest that strong adhesion capacity may not be the main virulence factor of F. columnare. Colony morphology change might be caused by phase variation, and different colony types isolated from infected fish may indicate different roles of the colony morphologies in the infection process of columnaris disease.
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Affiliation(s)
- Heidi M T Kunttu
- University of Jyväskylä, Department of Biological and Environmental Science, P.O. Box 35, FI-40014 Jyväskylä, Finland.
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Staroscik AM, Hunnicutt DW, Archibald KE, Nelson DR. Development of methods for the genetic manipulation of Flavobacterium columnare. BMC Microbiol 2008; 8:115. [PMID: 18620586 PMCID: PMC2483708 DOI: 10.1186/1471-2180-8-115] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2008] [Accepted: 07/11/2008] [Indexed: 11/10/2022] Open
Abstract
Background Flavobacterium columnare is the causative agent of columnaris disease, a disease affecting many freshwater fish species. Methods for the genetic manipulation for some of the species within the Bacteroidetes, including members of the genus Flavobacterium, have been described, but these methods were not adapted to work with F. columnare. Results As a first step toward developing a robust set of genetic tools for F. columnare, a protocol was developed to introduce the E. coli – Flavobacterium shuttle vector pCP29 into F. columnare strain C#2 by conjugal mating at an efficiency of 1.5 × 10-3 antibiotic-resistant transconjugants per recipient cell. Eight of eleven F. columnare strains tested were able to receive pCP29 using the protocol. pCP29 contains the cfxA and ermF genes, conferring both cefoxitin and erythromycin resistance to recipient cells. Selection for pCP29 introduction into F. columnare was dependent on cfxA, as ermF was found not to provide strong resistance to erythromycin. This is in contrast to other Flavobacterium species where ermF-based erythromycin resistance is strong. The green fluorescent protein gene (gfp) was introduced into F. columnare strains under the control of two different native Flavobacterium promoters, demonstrating the potential of this reporter system for the study of gene expression. The transposon Tn4351 was successfully introduced into F. columnare, but the method was dependent on selecting for erythromycin resistance. To work, low concentrations of antibiotic (1 μg ml-1) were used, and high levels of background growth occurred. These results demonstrate that Tn4351 functions in F. columnare but that it is not an effective mutagenesis tool due to its dependence on erythromycin selection. Attempts to generate mutants via homologous recombination met with limited success, suggesting that RecA dependent homologous recombination is rare in F. columnare. Conclusion The conjugation protocol developed as part of this study represents a significant first step towards the development of a robust set of genetic tools for the manipulation of F. columnare. The availability of this protocol will facilitate studies aimed at developing a deeper understanding of the virulence mechanisms of this important pathogen.
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Affiliation(s)
- Andrew M Staroscik
- Department of Cell and Molecular Biology, University of Rhode Island, Kingston, RI 02881, USA.
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Nelson SS, Bollampalli S, McBride MJ. SprB is a cell surface component of the Flavobacterium johnsoniae gliding motility machinery. J Bacteriol 2008; 190:2851-7. [PMID: 18281397 DOI: 10.1128/JB.01904-07] [Citation(s) in RCA: 74] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Cells of the gliding bacterium Flavobacterium johnsoniae move rapidly over surfaces by an unknown mechanism. Transposon insertions in sprB resulted in cells that were defective in gliding. SprB is a highly repetitive 669-kDa cell surface protein, and antibodies against SprB inhibited the motility of wild-type cells. Polystyrene microspheres coated with antibodies against SprB attached to and were rapidly propelled along the cell surface, suggesting that SprB is one of the outermost components of the motility machinery. The movement of SprB along the cell surface supports a model of gliding motility in which motors anchored to the cell wall rapidly propel cell surface adhesins.
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Liu J, McBride MJ, Subramaniam S. Cell surface filaments of the gliding bacterium Flavobacterium johnsoniae revealed by cryo-electron tomography. J Bacteriol 2007; 189:7503-6. [PMID: 17693495 PMCID: PMC2168446 DOI: 10.1128/jb.00957-07] [Citation(s) in RCA: 52] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Flavobacterium johnsoniae cells glide rapidly over surfaces by an as-yet-unknown mechanism. Using cryo-electron tomography, we show that wild-type cells display tufts of approximately 5-nm-wide cell surface filaments that appear to be anchored to the inner surface of the outer membrane. These filaments are absent in cells of a nonmotile gldF mutant but are restored upon expression of plasmid-encoded GldF, a component of a putative ATP-binding cassette transporter.
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Affiliation(s)
- Jun Liu
- Laboratory of Cell Biology, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892, USA
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Nelson SS, Glocka PP, Agarwal S, Grimm DP, McBride MJ. Flavobacterium johnsoniae SprA is a cell surface protein involved in gliding motility. J Bacteriol 2007; 189:7145-50. [PMID: 17644580 PMCID: PMC2045224 DOI: 10.1128/jb.00892-07] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Flavobacterium johnsoniae cells glide rapidly over surfaces by an unknown mechanism. Transposon-induced sprA mutants formed nonspreading colonies on agar, and the cells examined in wet mounts were deficient in attachment to surfaces and were almost completely nonmotile. Exposure of intact cells to proteinase K cleaved the 270-kDa SprA into several large peptides, suggesting that it is partially exposed on the cell surface.
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Affiliation(s)
- Shawn S Nelson
- Department of Biological Sciences, University of Wisconsin-Milwaukee, 3209 N. Maryland Ave., Milwaukee, WI 53211, USA
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Abstract
Sequences that mediate the initiation of transcription in Flavobacterium species are not well known. The majority of identified Flavobacterium promoter elements show homology to those of other members of the phylum Bacteroidetes, but not of proteobacteria, and they function poorly in Escherichia coli. In order to analyze the Flavobacterium promoter structure systematically, we investigated the -33 consensus element, -7 consensus element, and spacer length of the Flavobacterium ompA promoter by measuring the effects of site-directed mutations on promoter activity. The nonconserved sequences in the spacer region and in regions close to the consensus motifs were randomized in order to determine their importance for promoter activity. Most of the base substitutions in these regions caused large decreases in promoter activity. The optimal -33/-7 motifs (TTTG/TANNTTTG) were identical to Bacteroides fragilis sigma(ABfr) consensus -33/-7 promoter elements but lacked similarity to the E. coli sigma(70) promoter elements. The length of the spacer separating the -33 and -7 motifs of the ompA promoter also had a pronounced effect on promoter activity, with 19 bp being optimal. In addition to the consensus promoter elements and spacer length, the GC content of the core promoter sequences had a pronounced effect on Flavobacterium promoter activity. This information was used to conduct a scan of the Flavobacterium johnsoniae and B. fragilis genomes for putative promoters, resulting in 188 hits in B. fragilis and 109 hits in F. johnsoniae.
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Affiliation(s)
- Shicheng Chen
- Department of Microbiology and Molecular Genetics, Michigan State University, East Lansing, MI 48824, USA.
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Xie G, Bruce DC, Challacombe JF, Chertkov O, Detter JC, Gilna P, Han CS, Lucas S, Misra M, Myers GL, Richardson P, Tapia R, Thayer N, Thompson LS, Brettin TS, Henrissat B, Wilson DB, McBride MJ. Genome sequence of the cellulolytic gliding bacterium Cytophaga hutchinsonii. Appl Environ Microbiol 2007; 73:3536-46. [PMID: 17400776 PMCID: PMC1932680 DOI: 10.1128/aem.00225-07] [Citation(s) in RCA: 146] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The complete DNA sequence of the aerobic cellulolytic soil bacterium Cytophaga hutchinsonii, which belongs to the phylum Bacteroidetes, is presented. The genome consists of a single, circular, 4.43-Mb chromosome containing 3,790 open reading frames, 1,986 of which have been assigned a tentative function. Two of the most striking characteristics of C. hutchinsonii are its rapid gliding motility over surfaces and its contact-dependent digestion of crystalline cellulose. The mechanism of C. hutchinsonii motility is not known, but its genome contains homologs for each of the gld genes that are required for gliding of the distantly related bacteroidete Flavobacterium johnsoniae. Cytophaga-Flavobacterium gliding appears to be novel and does not involve well-studied motility organelles such as flagella or type IV pili. Many genes thought to encode proteins involved in cellulose utilization were identified. These include candidate endo-beta-1,4-glucanases and beta-glucosidases. Surprisingly, obvious homologs of known cellobiohydrolases were not detected. Since such enzymes are needed for efficient cellulose digestion by well-studied cellulolytic bacteria, C. hutchinsonii either has novel cellobiohydrolases or has an unusual method of cellulose utilization. Genes encoding proteins with cohesin domains, which are characteristic of cellulosomes, were absent, but many proteins predicted to be involved in polysaccharide utilization had putative D5 domains, which are thought to be involved in anchoring proteins to the cell surface.
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Affiliation(s)
- Gary Xie
- Los Alamos National Laboratory, New Mexico, USA
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Chen S, Bagdasarian M, Kaufman MG, Walker ED. Characterization of strong promoters from an environmental Flavobacterium hibernum strain by using a green fluorescent protein-based reporter system. Appl Environ Microbiol 2006; 73:1089-100. [PMID: 17189449 PMCID: PMC1828668 DOI: 10.1128/aem.01577-06] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
We developed techniques for the genetic manipulation of Flavobacterium species and used it to characterize several promoters found in these bacteria. Our studies utilized Flavobacterium hibernum strain W22, an environmental strain we isolated from tree hole habitats of mosquito larvae. Plasmids from F. hibernum strain W22 were more efficiently (approximately 1,250-fold) transferred by electroporation into F. hibernum strain W22 than those isolated from Escherichia coli, thus indicating that an efficient restriction barrier exists between these species. The strong promoter, tac, functional in proteobacteria, did not function in Flavobacterium strains. Therefore, a promoter-trap plasmid, pSCH03, containing a promoterless gfpmut3 gene was constructed. A library of 9,000 clones containing chromosomal fragments of F. hibernum strain W22 in pSCH03 was screened for their ability to drive expression of the promoterless gfpmut3 gene. Twenty strong promoters were used for further study. The transcription start points were determined from seven promoter clones by the 5' rapid amplification of cDNA ends technique. Promoter consensus sequences from Flavobacterium were identified as TAnnTTTG and TTG, where n is any nucleotide, centered approximately 7 and 33 bp upstream of the transcription start site, respectively. A putative novel ribosome binding site consensus sequence is proposed as TAAAA by aligning the 20-bp regions upstream of the translational start site in 25 genes. Our primary results demonstrate that at least some promoter and ribosome binding site motifs of Flavobacterium strains are unusual within the bacterial domain and suggest an early evolutionary divergence of this bacterial group. The techniques presented here allow for more detailed genetics-based studies and analyses of Flavobacterium species in the environment.
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Affiliation(s)
- S Chen
- Department of Microbiology and Molecular Genetics, Michigan State University, East Lansing, MI 48824, USA.
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Alvarez B, Secades P, Prieto M, McBride MJ, Guijarro JA. A mutation in Flavobacterium psychrophilum tlpB inhibits gliding motility and induces biofilm formation. Appl Environ Microbiol 2006; 72:4044-53. [PMID: 16751514 PMCID: PMC1489658 DOI: 10.1128/aem.00128-06] [Citation(s) in RCA: 63] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023] Open
Abstract
Flavobacterium psychrophilum is a psychrotrophic, fish-pathogenic bacterium belonging to the Cytophaga-Flavobacterium-Bacteroides group. Tn4351-induced mutants deficient in gliding motility, growth on iron-depleted media, and extracellular proteolytic activity were isolated. Some of these mutants were affected in only one of these characteristics, whereas others had defects in two or more. FP523, a mutant deficient in all of these properties, was studied further. FP523 had a Tn4351 insertion in tlpB (thiol oxidoreductase-like protein gene), which encodes a 41.4-kDa protein whose sequence does not exhibit high levels of similar to the sequences of proteins having known functions. TlpB has two domains; the N-terminal domains has five transmembrane regions, whereas the C-terminal domains has the Cys-X-X-Cys motif and other conserved motifs characteristic of thiol:disulfide oxidoreductases. Quantitative analysis of the thiol groups of periplasmic proteins revealed that TlpB is required for reduction of these groups. The tlpB gene is part of the fpt (F. psychrophilum thiol oxidoreductase) operon that contains two other genes, tlpA and tpiA, which encode a thiol:disulfide oxidoreductase and a triosephosphate isomerase, respectively. FP523 exhibited enhanced biofilm formation and decreased virulence and cytotoxicity. Complementation with the tlpB loci restored the wild-type phenotype. Gliding motility and biofilm formation appear to be antagonistic properties, which are both affected by TlpB.
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Affiliation(s)
- B Alvarez
- Area de Microbiología, Facultad de Medicina, Universidad de Oviedo, 33006 Oviedo, Asturias, Spain
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Furusawa G, Yoshikawa T, Takano Y, Mise K, Furusawa I, Okuno T, Sakata T. Characterization of cytoplasmic fibril structures found in gliding cells of Saprospira sp. Can J Microbiol 2006; 51:875-80. [PMID: 16333347 DOI: 10.1139/w05-081] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The cytoplasmic fibril structures of Saprospira sp. strain SS98-5 grown on a low-nutrient agar medium were purified from cell lysates treated with Triton X-100 and were observed by electron microscopy to be about 7 nm in width and 200-300 nm in length. SDS-PAGE of the fibril structures exhibited a single protein band with a molecular mass of 61 kDa. A Saprospira cytoplasmic fibril protein (SCFP), which is a subunit of the fibril structures, was digested with trypsin to oligopeptides and analyzed for amino acid sequences. A partial nucleotide sequence of the SCFP gene was determined after PCR using primers designated from the amino acid sequences of the oligopeptides. SCFP gene including DNA fragments were detected by Southern hybridization using the PCR product for an SCFP gene as a probe and were cloned to determine whole nucleotide sequences. The SCFP gene indicated relatively higher similarity to conserved hypothetical phage tail sheath proteins. A Western immunoblotting analysis showed that SCFP was significantly expressed in gliding cells as compared with nongliding cells. The above findings with the previously reported results suggest that the cytoplasmic fibril structures are possibly related to the gliding motility of Saprospira sp. strain SS98-5.
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Affiliation(s)
- Gou Furusawa
- Laboratory of Microbiology, Faculty of Fisheries, Kagoshima University, Kagoshima, Japan
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Abstract
secDF mutants of Flavobacterium johnsoniae were deficient in gliding motility and chitin utilization. Cells of the mutants had reduced levels of GldJ protein, which is required for both processes. SecDF is similar to Escherichia coli SecD and SecF, which are involved in protein secretion.
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Affiliation(s)
- Shawn S Nelson
- Department of Biological Sciences, 181 Lapham Hall, University of Wisconsin-Milwaukee, 3209 N. Maryland Avenue, Milwaukee, WI 53211, USA
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36
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Abstract
Cells of Flavobacterium johnsoniae glide rapidly over surfaces. The mechanism of F. johnsoniae gliding motility is not known. Eight gld genes required for gliding motility have been described. Disruption of any of these genes results in complete loss of gliding motility, deficiency in chitin utilization, and resistance to bacteriophages that infect wild-type cells. Two modified mariner transposons, HimarEm1 and HimarEm2, were constructed to allow the identification of additional motility genes. HimarEm1 and HimarEm2 each transposed in F. johnsoniae, and nonmotile mutants were identified and analyzed. Four novel motility genes, gldK, gldL, gldM, and gldN, were identified. GldK is similar in sequence to the lipoprotein GldJ, which is required for gliding. GldL, GldM, and GldN are not similar in sequence to proteins of known function. Cells with mutations in gldK, gldL, gldM, and gldN were defective in motility and chitin utilization and were resistant to bacteriophages that infect wild-type cells. Introduction of gldA, gldB, gldD, gldFG, gldH, gldI, and gldJ and the region spanning gldK, gldL, gldM, and gldN individually into 50 spontaneous and chemically induced nonmotile mutants restored motility to each of them, suggesting that few additional F. johnsoniae gld genes remain to be identified.
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Affiliation(s)
- Timothy F Braun
- Department of Biological Sciences, University of Wisconsin--Milwaukee, Milwaukee, Wisconsin 53201, USA
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Abstract
The presence of housekeeping gene promoters with a unique consensus sequence in Bacteroides fragilis, previously described by Bayley et al. (2000, FEMS Microbiol Lett 193: 149-154), suggested the existence of a particular primary sigma factor. The single rpoD-like gene observed in the B. fragilis genome, and similarly in those of other members of the Bacteroidetes phylum, was found to be essential. It encodes a protein, sigma(ABfr), of only 32.7 kDa that is produced with equal abundance during all phases of growth and was concluded to be the primary sigma factor. sigma(ABfr) and its orthologues in the Bacteroidetes are unusual primary sigma factors in that they lack region 1.1, have a unique signature made up of 29 strictly identical amino acids and are the only RpoD factors that cluster with the RpoS factors. Although binding to the Escherichia coli core RNA polymerase, sigma(ABfr) does not support transcription initiation from any promoter when it is part of the heterologous holoenzyme, while in the reconstituted homologous holoenzyme it does so only from typical B. fragilis, including rrs, promoters but not from the lacUV5 or RNA I promoters.
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Affiliation(s)
- Didier Vingadassalom
- INSERM E0004, Laboratoire de Recherche Moléculaire sur les Antibiotiques, Université Paris VI, 75270 Paris, France
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Abstract
Cells of Flavobacterium johnsoniae glide rapidly over surfaces by an unknown mechanism. Eight genes required for gliding motility have been described. Complementation of the nonmotile mutant UW102-48 identified another gene, gldJ, that is required for gliding. gldJ mutants formed nonspreading colonies, and individual cells were completely nonmotile. Like previously described nonmotile mutants, gldJ mutants were deficient in chitin utilization and were resistant to bacteriophages that infect wild-type cells. Cell fractionation and labeling studies with [(3)H]palmitate indicated that GldJ is a lipoprotein. Mutations in gldA, gldB, gldD, gldF, gldG, gldH, or gldI resulted in normal levels of gldJ transcript but decreased levels of GldJ protein. Expression of truncated GldJ protein in wild-type cells resulted in a severe motility defect. GldJ was found in regular bands that suggest the presence of a helical structure within the cell envelope.
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Affiliation(s)
- Timothy F Braun
- Department of Biological Sciences, 181 Lapham Hall, University of Wisconsin--Milwaukee, 3209 N. Maryland Ave., Milwaukee, WI 53211, USA
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39
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Abstract
Cells of Flavobacterium johnsoniae glide rapidly over surfaces by an unknown mechanism. Seven genes (gldA, gldB, gldD, gldF, gldG, gldH, and ftsX) that are required for gliding motility have been described. Complementation of the nonmotile mutants UW102-41, UW102-85, and UW102-92 identified another gene, gldI, that is required for gliding motility. gldI mutants formed nonspreading colonies, and individual cells were completely nonmotile. They were also resistant to bacteriophages that infect wild-type cells, and they failed to digest chitin. Introduction of wild-type gldI on a plasmid restored colony spreading, cell motility, phage sensitivity, and the ability to digest chitin to the gldI mutants. gldI encodes a predicted 199-amino-acid protein that localized to the membrane fraction. Labeling studies with [(3)H]palmitate indicated that GldI is a lipoprotein. GldI is similar to peptidyl-prolyl cis/trans-isomerases of the FK506-binding protein family and may be involved in folding cell envelope protein components of the motility machinery.
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Affiliation(s)
- Mark J McBride
- Department of Biological Sciences, University of Wisconsin-Milwaukee, Milwaukee, Wisconsin 53201, USA.
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Abstract
Flavobacterium johnsoniae, like many other members of the Cytophaga-Flavobacterium-Bacteroides group, displays rapid gliding motility. Cells of F. johnsoniae glide over surfaces at rates of up to 10 microm/s. Latex spheres added to F. johnsoniae bind to and are rapidly propelled along cells, suggesting that adhesive molecules move laterally along the cell surface during gliding. Genetic analyses have identified a number of gld genes that are required for gliding. Three Gld proteins are thought to be components of an ATP-binding-cassette transporter. Five other Gld proteins are lipoproteins that localize to the cytoplasmic membrane or outer membrane. Disruption of gld genes results not only in loss of motility, but also in resistance to bacteriophages that infect wild-type cells, and loss of the ability to digest the insoluble polysaccharide chitin. Two models that attempt to incorporate the available data to explain the mechanism of F. johnsoniae gliding are presented.
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Affiliation(s)
- Mark J McBride
- Department of Biological Sciences, University of Wisconsin-Milwaukee, Milwaukee, Wisconsin 53211, USA.
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McBride MJ, Braun TF, Brust JL. Flavobacterium johnsoniae GldH is a lipoprotein that is required for gliding motility and chitin utilization. J Bacteriol 2003; 185:6648-57. [PMID: 14594839 PMCID: PMC262120 DOI: 10.1128/jb.185.22.6648-6657.2003] [Citation(s) in RCA: 59] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Cells of Flavobacterium johnsoniae move rapidly over surfaces by gliding motility. The mechanism of this form of motility is not known. Six genes (gldA, gldB, gldD, gldF, gldG, and ftsX) that are required for gliding have been described. Tn4351 mutagenesis was used to identify another gene, gldH, which is required for cell movement. GldH mutants formed nonspreading colonies, and individual cells lacked the cell movements and ability to propel latex spheres along their surfaces that are characteristic of wild-type cells. gldH mutants also failed to digest chitin and were resistant to bacteriophages that infect wild-type cells. Introduction of pMM293, which carries wild-type gldH, restored to the gldH mutants colony spreading, cell motility, the ability to move latex spheres, phage sensitivity, and the ability to digest chitin. gldH encodes a predicted 141-amino-acid protein that localized to the membrane fraction. Labeling studies with [3H]palmitate demonstrated that GldH is a lipoprotein. GldB and GldD, which were previously described, also appear to be lipoproteins. GldH does not exhibit significant amino acid similarity to proteins of known function in the databases. Putative homologs of gldH of unknown function are found in motile (Cytophaga hutchinsonii) and apparently nonmotile (Bacteroides thetaiotaomicron, Bacteroides fragilis, Tannerella forsythensis, Porphyromonas gingivalis, and Prevotella intermedia) members of the Cytophaga-Flavobacterium-Bacteroides group.
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Affiliation(s)
- Mark J McBride
- Department of Biological Sciences, University of Wisconsin-Milwaukee, Milwaukee, Wisconsin 53201, USA.
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Abstract
Protein-related information is more accumulated rather than reduced to a synthetic view. Itemising properties of protein sequences is informative, so is the list of ingredients to do some cooking, but without a recipe, that is, quantification and chronology, understanding is incomplete. If the goal of accumulating information is to discover or reveal the function and related biochemical mechanisms, information has to be weighed and ordered. As a guideline, the weight of a piece of information should reflect how often it consistently occurs in various contexts. We propose a common sense approach to quantify and put data and information into perspective. Complete bacterial proteomes are individually mapped with the Pfam-A database of domains and protein family signatures in an attempt to assess the modularity of proteins at the level of a single proteome and the implications of a modular description of proteins for a functional interpretation. Poorly annotated proteins in the most documented bacteria (E. coli and B. subtilis) were considered in an attempt to formulate hypothesis on the basis of domain/module content.
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Hunnicutt DW, Kempf MJ, McBride MJ. Mutations in Flavobacterium johnsoniae gldF and gldG disrupt gliding motility and interfere with membrane localization of GldA. J Bacteriol 2002; 184:2370-8. [PMID: 11948149 PMCID: PMC134979 DOI: 10.1128/jb.184.9.2370-2378.2002] [Citation(s) in RCA: 60] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Flavobacterium johnsoniae moves rapidly over surfaces by a process known as gliding motility. The mechanism of this form of motility is not known. Four genes that are required for F. johnsoniae gliding motility, gldA, gldB, gldD, and ftsX, have recently been described. GldA is similar to the ATP-hydrolyzing components of ATP binding cassette (ABC) transporters. Tn4351 mutagenesis was used to identify two additional genes, gldF and gldG, that are required for cell movement. gldF and gldG appear to constitute an operon, and a Tn4351 insertion in gldF was polar on gldG. pMK314, which carries the entire gldFG region, restored motility to each of the gldF and gldG mutants. pMK321, which expresses GldG but not GldF, restored motility to each of the gldG mutants but did not complement the gldF mutant. GldF has six putative membrane-spanning segments and is similar in sequence to channel-forming components of ABC transporters. GldG is similar to putative accessory proteins of ABC transporters. It has two apparent membrane-spanning helices, one near the amino terminus and one near the carboxy terminus, and a large intervening loop that is predicted to reside in the periplasm. GldF and GldG are involved in membrane localization of GldA, suggesting that GldA, GldF, and GldG may interact to form a transporter. F. johnsoniae gldA is not closely linked to gldFG, but the gldA, gldF, and gldG homologs of the distantly related gliding bacterium Cytophaga hutchinsonii are arranged in what appears to be an operon. The exact roles of F. johnsoniae GldA, GldF, and GldG in gliding are not known. Sequence similarities of GldA to components of other ABC transporters suggest that the Gld transporter may be involved in export of some material to the periplasm, outer membrane, or beyond.
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Affiliation(s)
- David W Hunnicutt
- Department of Biological Sciences, University of Wisconsin-Milwaukee, Milwaukee, Wisconsin 53201, USA
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