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Jeong GJ, Khan F, Tabassum N, Kim YM. Motility of Acinetobacter baumannii: regulatory systems and controlling strategies. Appl Microbiol Biotechnol 2024; 108:3. [PMID: 38159120 DOI: 10.1007/s00253-023-12975-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [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: 10/05/2023] [Revised: 11/08/2023] [Accepted: 11/13/2023] [Indexed: 01/03/2024]
Abstract
Acinetobacter baumannii is a Gram-negative opportunistic zoonotic pathogenic bacterium that causes nosocomial infections ranging from minor to life-threatening. The clinical importance of this zoonotic pathogen is rapidly increasing due to the development of multiple resistance mechanisms and the synthesis of numerous virulence factors. Although no flagellum-mediated motility exists, it may move through twitching or surface-associated motility. Twitching motility is a coordinated multicellular movement caused by the extension, attachment, and retraction of type IV pili, which are involved in surface adherence and biofilm formation. Surface-associated motility is a kind of movement that does not need appendages and is most likely driven by the release of extra polymeric molecules. This kind of motility is linked to the production of 1,3-diaminopropane, lipooligosaccharide formation, natural competence, and efflux pump proteins. Since A. baumannii's virulence qualities are directly tied to motility, it is possible that its motility may be used as a specialized preventative or therapeutic measure. The current review detailed the signaling mechanism and involvement of various proteins in controlling A. baumannii motility. As a result, we have thoroughly addressed the role of natural and synthetic compounds that impede A. baumannii motility, as well as the underlying action mechanisms. Understanding the regulatory mechanisms behind A. baumannii's motility features will aid in the development of therapeutic drugs to control its infection. KEY POINTS: • Acinetobacter baumannii exhibits multiple resistance mechanisms. • A. baumannii can move owing to twitching and surface-associated motility. • Natural and synthetic compounds can attenuate A. baumannii motility.
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Affiliation(s)
- Geum-Jae Jeong
- Department of Food Science and Technology, Pukyong National University, Busan, 48513, Republic of Korea
| | - Fazlurrahman Khan
- Institute of Fisheries Sciences, Pukyong National University, Busan, 48513, Republic of Korea.
- Marine Integrated Biomedical Technology Center, The National Key Research Institutes in Universities, Pukyong National University, Busan, 48513, Republic of Korea.
- Research Center for Marine Integrated Bionics Technology, Pukyong National University, Busan, 48513, Republic of Korea.
| | - Nazia Tabassum
- Marine Integrated Biomedical Technology Center, The National Key Research Institutes in Universities, Pukyong National University, Busan, 48513, Republic of Korea
- Research Center for Marine Integrated Bionics Technology, Pukyong National University, Busan, 48513, Republic of Korea
| | - Young-Mog Kim
- Department of Food Science and Technology, Pukyong National University, Busan, 48513, Republic of Korea.
- Marine Integrated Biomedical Technology Center, The National Key Research Institutes in Universities, Pukyong National University, Busan, 48513, Republic of Korea.
- Research Center for Marine Integrated Bionics Technology, Pukyong National University, Busan, 48513, Republic of Korea.
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Chen X, Yang G, Quan X, Zhu S, Qin B, Shou D, Zhuang L. Significance of a minor pilin PilV in biofilm cohesion of Geobacter sulfurreducens. Sci Total Environ 2024; 927:172242. [PMID: 38582122 DOI: 10.1016/j.scitotenv.2024.172242] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/14/2023] [Revised: 04/03/2024] [Accepted: 04/03/2024] [Indexed: 04/08/2024]
Abstract
Bacterial adhesion plays a vital role in forming and shaping the structure of electroactive biofilms that are essential for the performance of bioelectrochemical systems (BESs). Type IV pili are known to mediate cell adhesion in many Gram-negative bacteria, but the mechanism of pili-mediated cell adhesion of Geobacter species on anode surface remains unclear. Herein, a minor pilin PilV2 was found to be essential for cell adhesion ability of Geobacter sulfurreducens since the lack of pilV2 gene depressed the cell adhesion capability by 81.2% in microplate and the anodic biofilm density by 23.1 % at -0.1 V and 37.7 % at -0.3 V in BESs. The less cohesiveness of mutant biofilms increased the charge transfer resistance and biofilm resistance, which correspondingly lowered current generation of the pilV2-deficient strain by up to 63.2 % compared with that of the wild-type strain in BESs. The deletion of pilV2 posed an insignificant effect on the production of extracellular polysaccharides, pili, extracellular cytochromes and electron shuttles that are involved in biofilm formation or extracellular electron transfer (EET) process. This study demonstrated the significance of pilV2 gene in cell adhesion and biofilm formation of G. sulfurreducens, as well as the importance of pili-mediated adhesion for EET of electroactive biofilm.
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Affiliation(s)
- Xiaochun Chen
- Guangdong Key Laboratory of Environmental Pollution and Health, School of Environment, Jinan University, Guangzhou 510632, China
| | - Guiqin Yang
- Guangdong Key Laboratory of Environmental Pollution and Health, School of Environment, Jinan University, Guangzhou 510632, China
| | - Xiaoyun Quan
- Guangdong Key Laboratory of Environmental Pollution and Health, School of Environment, Jinan University, Guangzhou 510632, China
| | - Siyue Zhu
- Guangdong Key Laboratory of Environmental Pollution and Health, School of Environment, Jinan University, Guangzhou 510632, China
| | - Baoli Qin
- Guangdong Key Laboratory of Environmental Pollution and Health, School of Environment, Jinan University, Guangzhou 510632, China
| | - Danyang Shou
- Guangdong Key Laboratory of Environmental Pollution and Health, School of Environment, Jinan University, Guangzhou 510632, China
| | - Li Zhuang
- Guangdong Key Laboratory of Environmental Pollution and Health, School of Environment, Jinan University, Guangzhou 510632, China.
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Cui R, Wang QA, Guo L, Li DF. The ligand binding domain of a type IV pilus chemoreceptor PilJ has a different fold from that of another PilJ-type receptor McpN. Biochem Biophys Res Commun 2024; 706:149765. [PMID: 38484573 DOI: 10.1016/j.bbrc.2024.149765] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2024] [Revised: 03/05/2024] [Accepted: 03/08/2024] [Indexed: 03/24/2024]
Abstract
Bacterial chemoreceptors sense the extracellular signals and regulate bacterial motilities, biofilm formation, etc. The periplasmic ligand binding domains of chemoreceptors occur as different structural folds and recognize a diversity of chemical molecules. In Pseudomonas aeruginosa (PAO1), two bacterial chemoreceptors, McpN (PA2788) and PilJ (PA0411), are proposed to both contain a PilJ-like ligand-binding domain (LBD) (Pfam motif PF13675) and involved in nitrate chemotaxis and type IV pilus-mediated motility, respectively. The LBDs of McpN and PilJ consist of 135 and 263 residues, respectively, and share very low sequence identity, suggesting they might occur as different structures. Here, we found that PilJ-LBD folded into an HBM module, the same as the sensor domains of McpS-LBD and TorS-LBD, but it differed from that of McpN-LBD. We also observed a trimer in SEC and AUC and proposed a trimeric model based on the crystal structure. Based on the sequence, we classified the Pfam containing McpN-LBD and PilJ-LBD into three classes: sPilJ (single PilJ) represented by McpN-LBD with only one PilJ domain, dPilJ (dual PilJ) that contained dual PilJ domains, and hPilJ (hybrid PilJ) that comprises of a PilJ domain and another non-PilJ domain. Our work indicates a significant structural difference between the ligand binding domains of PilJ and McpN and will help our further study on both kinds of chemoreceptors.
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Affiliation(s)
- Rui Cui
- State Key Laboratory of Microbial Resources, Institute of Microbiology, Chinese Academy of Sciences, Beijing, 100101, PR China; School of Life Sciences, University of Chinese Academy of Sciences, Beijing, 100049, PR China
| | - Qi-An Wang
- State Key Laboratory of Microbial Resources, Institute of Microbiology, Chinese Academy of Sciences, Beijing, 100101, PR China
| | - Lu Guo
- State Key Laboratory of Microbial Resources, Institute of Microbiology, Chinese Academy of Sciences, Beijing, 100101, PR China
| | - De-Feng Li
- State Key Laboratory of Microbial Resources, Institute of Microbiology, Chinese Academy of Sciences, Beijing, 100101, PR China; School of Life Sciences, University of Chinese Academy of Sciences, Beijing, 100049, PR China.
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Treuner-Lange A, Zheng W, Viljoen A, Lindow S, Herfurth M, Dufrêne YF, Søgaard-Andersen L, Egelman EH. Tight-packing of large pilin subunits provides distinct structural and mechanical properties for the Myxococcus xanthus type IVa pilus. Proc Natl Acad Sci U S A 2024; 121:e2321989121. [PMID: 38625941 DOI: 10.1073/pnas.2321989121] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [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: 12/20/2023] [Accepted: 03/07/2024] [Indexed: 04/18/2024] Open
Abstract
Type IVa pili (T4aP) are ubiquitous cell surface filaments important for surface motility, adhesion to surfaces, DNA uptake, biofilm formation, and virulence. T4aP are built from thousands of copies of the major pilin subunit and tipped by a complex composed of minor pilins and in some systems also the PilY1 adhesin. While major pilins of structurally characterized T4aP have lengths of <165 residues, the major pilin PilA of Myxococcus xanthus is unusually large with 208 residues. All major pilins have a conserved N-terminal domain and a variable C-terminal domain, and the additional residues of PilA are due to a larger C-terminal domain. We solved the structure of the M. xanthus T4aP (T4aPMx) at a resolution of 3.0 Å using cryo-EM. The T4aPMx follows the structural blueprint of other T4aP with the pilus core comprised of the interacting N-terminal α1-helices, while the globular domains decorate the T4aP surface. The atomic model of PilA built into this map shows that the large C-terminal domain has more extensive intersubunit contacts than major pilins in other T4aP. As expected from these greater contacts, the bending and axial stiffness of the T4aPMx is significantly higher than that of other T4aP and supports T4aP-dependent motility on surfaces of different stiffnesses. Notably, T4aPMx variants with interrupted intersubunit interfaces had decreased bending stiffness, pilus length, and strongly reduced motility. These observations support an evolutionary scenario whereby the large major pilin enables the formation of a rigid T4aP that expands the environmental conditions in which the T4aP system functions.
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Affiliation(s)
- Anke Treuner-Lange
- Department of Ecophysiology, Max Planck Institute for Terrestrial Microbiology, Marburg 35043, Germany
| | - Weili Zheng
- Department of Biochemistry and Molecular Genetics, University of Virginia School of Medicine, Charlottesville, VA 22903
| | - Albertus Viljoen
- Louvain Institute of Biomolecular Science and Technology, UCLouvain, Louvain-la-Neuve B-1348, Belgium
| | - Steffi Lindow
- Department of Ecophysiology, Max Planck Institute for Terrestrial Microbiology, Marburg 35043, Germany
| | - Marco Herfurth
- Department of Ecophysiology, Max Planck Institute for Terrestrial Microbiology, Marburg 35043, Germany
| | - Yves F Dufrêne
- Louvain Institute of Biomolecular Science and Technology, UCLouvain, Louvain-la-Neuve B-1348, Belgium
| | - Lotte Søgaard-Andersen
- Department of Ecophysiology, Max Planck Institute for Terrestrial Microbiology, Marburg 35043, Germany
| | - Edward H Egelman
- Department of Biochemistry and Molecular Genetics, University of Virginia School of Medicine, Charlottesville, VA 22903
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Meng R, Xing Z, Chang JY, Yu Z, Thongchol J, Xiao W, Wang Y, Chamakura K, Zeng Z, Wang F, Young R, Zeng L, Zhang J. Structural basis of Acinetobacter type IV pili targeting by an RNA virus. Nat Commun 2024; 15:2746. [PMID: 38553443 PMCID: PMC10980823 DOI: 10.1038/s41467-024-47119-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2023] [Accepted: 03/20/2024] [Indexed: 04/02/2024] Open
Abstract
Acinetobacters pose a significant threat to human health, especially those with weakened immune systems. Type IV pili of acinetobacters play crucial roles in virulence and antibiotic resistance. Single-stranded RNA bacteriophages target the bacterial retractile pili, including type IV. Our study delves into the interaction between Acinetobacter phage AP205 and type IV pili. Using cryo-electron microscopy, we solve structures of the AP205 virion with an asymmetric dimer of maturation proteins, the native Acinetobacter type IV pili bearing a distinct post-translational pilin cleavage, and the pili-bound AP205 showing its maturation proteins adapted to pilin modifications, allowing each phage to bind to one or two pili. Leveraging these results, we develop a 20-kilodalton AP205-derived protein scaffold targeting type IV pili in situ, with potential for research and diagnostics.
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Affiliation(s)
- Ran Meng
- Center for Phage Technology, Department of Biochemistry and Biophysics, Texas A&M University, College Station, TX, 77843, USA
- Yale University, New Haven, CT, 06520, USA
| | - Zhongliang Xing
- Center for Phage Technology, Department of Biochemistry and Biophysics, Texas A&M University, College Station, TX, 77843, USA
| | - Jeng-Yih Chang
- Center for Phage Technology, Department of Biochemistry and Biophysics, Texas A&M University, College Station, TX, 77843, USA
- UMass Chan Medical School, Worcester, MA, 01655, USA
| | - Zihao Yu
- Center for Phage Technology, Department of Biochemistry and Biophysics, Texas A&M University, College Station, TX, 77843, USA
| | - Jirapat Thongchol
- Center for Phage Technology, Department of Biochemistry and Biophysics, Texas A&M University, College Station, TX, 77843, USA
| | - Wen Xiao
- Center for Phage Technology, Department of Biochemistry and Biophysics, Texas A&M University, College Station, TX, 77843, USA
| | - Yuhang Wang
- Center for Phage Technology, Department of Biochemistry and Biophysics, Texas A&M University, College Station, TX, 77843, USA
| | - Karthik Chamakura
- Center for Phage Technology, Department of Biochemistry and Biophysics, Texas A&M University, College Station, TX, 77843, USA
- Armata Pharmaceuticals, Inc., Marina del Rey, CA, 90292, USA
| | - Zhiqi Zeng
- Center for Phage Technology, Department of Biochemistry and Biophysics, Texas A&M University, College Station, TX, 77843, USA
| | - Fengbin Wang
- Department of Biochemistry and Molecular Genetics, Heersink School of Medicine, University of Alabama at Birmingham, Birmingham, AL, 35294, USA
| | - Ry Young
- Center for Phage Technology, Department of Biochemistry and Biophysics, Texas A&M University, College Station, TX, 77843, USA
| | - Lanying Zeng
- Center for Phage Technology, Department of Biochemistry and Biophysics, Texas A&M University, College Station, TX, 77843, USA
| | - Junjie Zhang
- Center for Phage Technology, Department of Biochemistry and Biophysics, Texas A&M University, College Station, TX, 77843, USA.
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Fernandez-Martinez D, Kong Y, Goussard S, Zavala A, Gastineau P, Rey M, Ayme G, Chamot-Rooke J, Lafaye P, Vos M, Mechaly A, Duménil G. Cryo-EM structures of type IV pili complexed with nanobodies reveal immune escape mechanisms. Nat Commun 2024; 15:2414. [PMID: 38499587 PMCID: PMC10948894 DOI: 10.1038/s41467-024-46677-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2023] [Accepted: 03/01/2024] [Indexed: 03/20/2024] Open
Abstract
Type IV pili (T4P) are prevalent, polymeric surface structures in pathogenic bacteria, making them ideal targets for effective vaccines. However, bacteria have evolved efficient strategies to evade type IV pili-directed antibody responses. Neisseria meningitidis are prototypical type IV pili-expressing Gram-negative bacteria responsible for life threatening sepsis and meningitis. This species has evolved several genetic strategies to modify the surface of its type IV pili, changing pilin subunit amino acid sequence, nature of glycosylation and phosphoforms, but how these modifications affect antibody binding at the structural level is still unknown. Here, to explore this question, we determine cryo-electron microscopy (cryo-EM) structures of pili of different sequence types with sufficiently high resolution to visualize posttranslational modifications. We then generate nanobodies directed against type IV pili which alter pilus function in vitro and in vivo. Cyro-EM in combination with molecular dynamics simulation of the nanobody-pilus complexes reveals how the different types of pili surface modifications alter nanobody binding. Our findings shed light on the impressive complementarity between the different strategies used by bacteria to avoid antibody binding. Importantly, we also show that structural information can be used to make informed modifications in nanobodies as countermeasures to these immune evasion mechanisms.
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Affiliation(s)
- David Fernandez-Martinez
- Institut Pasteur, Université Paris Cité, INSERM UMR1225, Pathogenesis of Vascular Infections, 75015, Paris, France
| | - Youxin Kong
- Institut Pasteur, Université Paris Cité, INSERM UMR1225, Pathogenesis of Vascular Infections, 75015, Paris, France
- Sanofi R&D, Integrated Drug Discovery, CRVA, 94403, Vitry-sur-Seine, France
| | - Sylvie Goussard
- Institut Pasteur, Université Paris Cité, INSERM UMR1225, Pathogenesis of Vascular Infections, 75015, Paris, France
| | - Agustin Zavala
- Institut Pasteur, Université Paris Cité, INSERM UMR1225, Pathogenesis of Vascular Infections, 75015, Paris, France
| | - Pauline Gastineau
- Institut Pasteur, Université Paris Cité, INSERM UMR1225, Pathogenesis of Vascular Infections, 75015, Paris, France
| | - Martial Rey
- Institut Pasteur, Université Paris-Cité, CNRS, UAR 2024, Mass Spectrometry for Biology, 75015, Paris, France
| | - Gabriel Ayme
- Institut Pasteur, Université Paris-Cité, CNRS-UMR 3528, Antibody Engineering Platform, 75015, Paris, France
| | - Julia Chamot-Rooke
- Institut Pasteur, Université Paris-Cité, CNRS, UAR 2024, Mass Spectrometry for Biology, 75015, Paris, France
| | - Pierre Lafaye
- Institut Pasteur, Université Paris-Cité, CNRS-UMR 3528, Antibody Engineering Platform, 75015, Paris, France
| | - Matthijn Vos
- NanoImaging Core Facility, Center for Technological Resources and Research, Institut Pasteur, 75015, Paris, France
| | - Ariel Mechaly
- Institut Pasteur, Crystallography Platform-C2RT, CNRS-UMR 3528, Université Paris Cité, Paris, France
| | - Guillaume Duménil
- Institut Pasteur, Université Paris Cité, INSERM UMR1225, Pathogenesis of Vascular Infections, 75015, Paris, France.
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Gerlach RG, Wittmann I, Heinrich L, Pinkenburg O, Meyer T, Elpers L, Schmidt C, Hensel M, Schnare M. Subversion of a family of antimicrobial proteins by Salmonella enterica. Front Cell Infect Microbiol 2024; 14:1375887. [PMID: 38505286 PMCID: PMC10948614 DOI: 10.3389/fcimb.2024.1375887] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2024] [Accepted: 02/19/2024] [Indexed: 03/21/2024] Open
Abstract
Salmonella enterica is a food-borne pathogen able to cause a wide spectrum of diseases ranging from mild gastroenteritis to systemic infections. During almost all stages of the infection process Salmonella is likely to be exposed to a wide variety of host-derived antimicrobial peptides (AMPs). AMPs are important components of the innate immune response which integrate within the bacterial membrane, thus forming pores which lead ultimately to bacterial killing. In contrast to other AMPs Bactericidal/Permeability-increasing Protein (BPI) displayed only weak bacteriostatic or bactericidal effects towards Salmonella enterica sv. Typhimurium (STM) cultures. Surprisingly, we found that sub-antimicrobial concentrations of BPI fold-containing (BPIF) superfamily members mediated adhesion of STM depending on pre-formed type 1 fimbriae. BPIF proteins directly bind to type 1 fimbriae through mannose-containing oligosaccharide modifications. Fimbriae decorated with BPIF proteins exhibit extended binding specificity, allowing for bacterial adhesion on a greater variety of abiotic and biotic surfaces likely promoting host colonization. Further, fimbriae significantly contributed to the resistance against BPI, probably through sequestration of the AMP before membrane interaction. In conclusion, functional subversion of innate immune proteins of the BPIF family through binding to fimbriae promotes Salmonella virulence by survival of host defense and promotion of host colonization.
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Affiliation(s)
- Roman G. Gerlach
- Institute of Clinical Microbiology, Immunology and Hygiene, University Hospital of Erlangen and Friedrich-Alexander-University (FAU) Erlangen-Nuremberg, Erlangen, Germany
- Robert Koch Institute, Wernigerode, Germany
| | - Irene Wittmann
- Institute of Clinical Microbiology, Immunology and Hygiene, University Hospital of Erlangen and Friedrich-Alexander-University (FAU) Erlangen-Nuremberg, Erlangen, Germany
| | | | - Olaf Pinkenburg
- Institute for Immunology, Philipps-University Marburg, Marburg, Germany
| | - Torben Meyer
- Institute for Immunology, Philipps-University Marburg, Marburg, Germany
| | - Laura Elpers
- Division of Microbiology and CellNanOs – Center of Cellular Nanoanalytics Osnabrück, School of Biology/Chemistry, University Osnabrück, Osnabrück, Germany
| | | | - Michael Hensel
- Division of Microbiology and CellNanOs – Center of Cellular Nanoanalytics Osnabrück, School of Biology/Chemistry, University Osnabrück, Osnabrück, Germany
| | - Markus Schnare
- Institute for Immunology, Philipps-University Marburg, Marburg, Germany
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Dhehibi A, Terrak M, Seddik MM, Hammadi M, Salhi I. Development of a bispecific Nanobody anti-F17 fimbria as a potential therapeutic tool. Protein Expr Purif 2024; 215:106411. [PMID: 38056514 DOI: 10.1016/j.pep.2023.106411] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2023] [Revised: 11/28/2023] [Accepted: 11/29/2023] [Indexed: 12/08/2023]
Abstract
Pathogenic strains of Escherichia coli F17+ are associated with various intestinal and extra-intestinal pathologies, including diarrhea, and result in significant animal mortality. These infections rely on the expression of virulence factors, such as F17 fimbriae, for adhesion. F17 fimbriae form a protective layer on the surface of E. coli bacteria, consisting of a major structural subunit, F17A, and a minor functional subunit, F17G. Because of the evolution of bacterial resistance, conventional antibiotic treatments have limited efficacy. Therefore, there is a pressing need to develop novel therapeutic tools. In this study, we cloned and produced the F17G protein. We then immunized a camel with the purified F17G protein and constructed a VHH library consisting of 2 × 109 clones. The library was then screened against F17G protein using phage display technology. Through this process, we identified an anti-F17G nanobody that was subsequently linked, via a linker, to an anti-F17A nanobody, resulting in the creation of an effective bispecific nanobody. Comprehensive characterization of this bispecific nanobody demonstrated excellent production, specific binding capacity to both recombinant forms of the two F17 antigens and the E. coli F17+ strain, remarkable stability in camel serum, and superior resistance to pepsin protease. The successful generation of this bispecific nanobody with excellent production, specific binding capacity and stability highlights its potential as a valuable tool for fighting infections caused by pathogenic E. coli F17+ strain.
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Affiliation(s)
- Asma Dhehibi
- Livestock and Wildlife Laboratory (LR16IRA04), Arid Lands Institute (I.R.A), University of Gabès, Médenine, 4119, Tunisia.
| | - Mohammed Terrak
- InBioS-Centre for Protein Engineering, University of Liege, B-4000, Liege, Belgium
| | - Mabrouk-Mouldi Seddik
- Livestock and Wildlife Laboratory (LR16IRA04), Arid Lands Institute (I.R.A), University of Gabès, Médenine, 4119, Tunisia
| | - Mohamed Hammadi
- Livestock and Wildlife Laboratory (LR16IRA04), Arid Lands Institute (I.R.A), University of Gabès, Médenine, 4119, Tunisia
| | - Imed Salhi
- Livestock and Wildlife Laboratory (LR16IRA04), Arid Lands Institute (I.R.A), University of Gabès, Médenine, 4119, Tunisia
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9
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Costa TRD, Patkowski JB, Macé K, Christie PJ, Waksman G. Structural and functional diversity of type IV secretion systems. Nat Rev Microbiol 2024; 22:170-185. [PMID: 37814112 DOI: 10.1038/s41579-023-00974-3] [Citation(s) in RCA: 8] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/13/2023] [Indexed: 10/11/2023]
Abstract
Considerable progress has been made in recent years in the structural and molecular biology of type IV secretion systems in Gram-negative bacteria. The latest advances have substantially improved our understanding of the mechanisms underlying the recruitment and delivery of DNA and protein substrates to the extracellular environment or target cells. In this Review, we aim to summarize these exciting structural and molecular biology findings and to discuss their functional implications for substrate recognition, recruitment and translocation, as well as the biogenesis of extracellular pili. We also describe adaptations necessary for deploying a breadth of processes, such as bacterial survival, host-pathogen interactions and biotic and abiotic adhesion. We highlight the functional and structural diversity that allows this extremely versatile secretion superfamily to function under different environmental conditions and in different bacterial species. Additionally, we emphasize the importance of further understanding the mechanism of type IV secretion, which will support us in combating antimicrobial resistance and treating type IV secretion system-related infections.
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Affiliation(s)
- Tiago R D Costa
- Centre for Bacterial Resistance Biology, Department of Life Sciences, Imperial College, London, UK.
| | - Jonasz B Patkowski
- Centre for Bacterial Resistance Biology, Department of Life Sciences, Imperial College, London, UK
| | - Kévin Macé
- Institute of Structural and Molecular Biology, Birkbeck and UCL, London, UK
- Institut de Génétique et Développement de Rennes (IGDR), Université de Rennes and CNRS, Rennes, France
| | - Peter J Christie
- Department of Microbiology and Molecular Genetics, McGovern Medical School at UTHealth, Houston, TX, USA.
| | - Gabriel Waksman
- Institute of Structural and Molecular Biology, Birkbeck and UCL, London, UK.
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10
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Yarrington KD, Shendruk TN, Limoli DH. The type IV pilus chemoreceptor PilJ controls chemotaxis of one bacterial species towards another. PLoS Biol 2024; 22:e3002488. [PMID: 38349934 PMCID: PMC10896506 DOI: 10.1371/journal.pbio.3002488] [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] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2023] [Revised: 02/26/2024] [Accepted: 01/05/2024] [Indexed: 02/15/2024] Open
Abstract
Bacteria live in social communities, where the ability to sense and respond to interspecies and environmental signals is critical for survival. We previously showed the pathogen Pseudomonas aeruginosa detects secreted peptides from bacterial competitors and navigates through interspecies signal gradients using pilus-based motility. Yet, it was unknown whether P. aeruginosa utilizes a designated chemosensory system for this behavior. Here, we performed a systematic genetic analysis of a putative pilus chemosensory system, followed by high-speed live-imaging and single-cell tracking, to reveal behaviors of mutants that retain motility but are blind to interspecies signals. The enzymes predicted to methylate (PilK) and demethylate (ChpB) the putative pilus chemoreceptor, PilJ, are necessary for cells to control the direction of migration. While these findings implicate PilJ as a bona fide chemoreceptor, such function had yet to be experimentally defined, as full-length PilJ is essential for motility. Thus, we constructed systematic genetic modifications of PilJ and found that without the predicted ligand binding domains or predicted methylation sites, cells lose the ability to detect competitor gradients, despite retaining pilus-mediated motility. Chemotaxis trajectory analysis revealed that increased probability and size of P. aeruginosa pilus-mediated steps towards S. aureus peptides, versus steps away, determines motility bias in wild type cells. However, PilJ mutants blind to interspecies signals take less frequent steps towards S. aureus or steps of equal size towards and away. Collectively, this work uncovers the chemosensory nature of PilJ, provides insight into how cell movements are biased during pilus-based chemotaxis, and identifies chemotactic interactions necessary for bacterial survival in polymicrobial communities, revealing putative pathways where therapeutic intervention might disrupt bacterial communication.
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Affiliation(s)
- Kaitlin D. Yarrington
- Department of Microbiology and Immunology, Carver College of Medicine, University of Iowa, Iowa City, Iowa, United States of America
| | - Tyler N. Shendruk
- School of Physics and Astronomy, The University of Edinburgh, Edinburgh, United Kingdom
| | - Dominique H. Limoli
- Department of Microbiology and Immunology, Carver College of Medicine, University of Iowa, Iowa City, Iowa, United States of America
- Department of Biology, Indiana University, Bloomington, Indiana, United States of America
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11
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Liu X, Tachiyama S, Zhou X, Mathias RA, Bonny SQ, Khan MF, Xin Y, Roujeinikova A, Liu J, Ottemann KM. Bacterial flagella hijack type IV pili proteins to control motility. Proc Natl Acad Sci U S A 2024; 121:e2317452121. [PMID: 38236729 PMCID: PMC10823254 DOI: 10.1073/pnas.2317452121] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [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: 10/08/2023] [Accepted: 11/27/2023] [Indexed: 01/23/2024] Open
Abstract
Bacterial flagella and type IV pili (TFP) are surface appendages that enable motility and mechanosensing through distinct mechanisms. These structures were previously thought to have no components in common. Here, we report that TFP and some flagella share proteins PilO, PilN, and PilM, which we identified as part of the Helicobacter pylori flagellar motor. H. pylori mutants lacking PilO or PilN migrated better than wild type in semisolid agar because they continued swimming rather than aggregated into microcolonies, mimicking the TFP-regulated surface response. Like their TFP homologs, flagellar PilO/PilN heterodimers formed a peripheral cage that encircled the flagellar motor. These results indicate that PilO and PilN act similarly in flagella and TFP by differentially regulating motility and microcolony formation when bacteria encounter surfaces.
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Affiliation(s)
- Xiaolin Liu
- Department of Microbiology and Environmental Toxicology, University of California, Santa Cruz, CA95064
| | - Shoichi Tachiyama
- Department of Microbial Pathogenesis, Yale School of Medicine, New Haven, CT06536
- Microbial Sciences Institute, Yale University, West Haven, CT06516
| | - Xiaotian Zhou
- Infection and Immunity Program, Department of Microbiology, Monash Biomedicine Discovery Institute, Monash University, Clayton, VIC3800, Australia
| | - Rommel A. Mathias
- Infection and Immunity Program, Department of Microbiology, Monash Biomedicine Discovery Institute, Monash University, Clayton, VIC3800, Australia
- Department of Biochemistry and Molecular Biology, Monash University, Clayton, VIC3800, Australia
| | - Sharmin Q. Bonny
- Infection and Immunity Program, Department of Microbiology, Monash Biomedicine Discovery Institute, Monash University, Clayton, VIC3800, Australia
| | - Mohammad F. Khan
- Infection and Immunity Program, Department of Microbiology, Monash Biomedicine Discovery Institute, Monash University, Clayton, VIC3800, Australia
| | - Yue Xin
- Infection and Immunity Program, Department of Microbiology, Monash Biomedicine Discovery Institute, Monash University, Clayton, VIC3800, Australia
| | - Anna Roujeinikova
- Infection and Immunity Program, Department of Microbiology, Monash Biomedicine Discovery Institute, Monash University, Clayton, VIC3800, Australia
- Department of Biochemistry and Molecular Biology, Monash University, Clayton, VIC3800, Australia
| | - Jun Liu
- Department of Microbial Pathogenesis, Yale School of Medicine, New Haven, CT06536
- Microbial Sciences Institute, Yale University, West Haven, CT06516
| | - Karen M. Ottemann
- Department of Microbiology and Environmental Toxicology, University of California, Santa Cruz, CA95064
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12
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Beltrán L, Torsilieri H, Patkowski JB, Yang JE, Casanova J, Costa TRD, Wright ER, Egelman EH. The mating pilus of E. coli pED208 acts as a conduit for ssDNA during horizontal gene transfer. mBio 2024; 15:e0285723. [PMID: 38051116 PMCID: PMC10790687 DOI: 10.1128/mbio.02857-23] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [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: 10/23/2023] [Accepted: 10/30/2023] [Indexed: 12/07/2023] Open
Abstract
IMPORTANCE Bacteria are constantly exchanging DNA, which constitutes horizontal gene transfer. While some of these occurs by a non-specific process called natural transformation, some occurs by a specific mating between a donor and a recipient cell. In specific conjugation, the mating pilus is extended from the donor cell to make contact with the recipient cell, but whether DNA is actually transferred through this pilus or by another mechanism involving the type IV secretion system complex without the pilus has been an open question. Using Escherichia coli, we show that DNA can be transferred through this pilus between a donor and a recipient cell that has not established a tight mating junction, providing a new picture for the role of this pilus.
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Affiliation(s)
- Leticia Beltrán
- Department of Biochemistry and Molecular Genetics, University of Virginia, Charlottesville, Virginia, USA
| | - Holly Torsilieri
- Department of Molecular Cell Biology, University of Virginia, Charlottesville, Virginia, USA
| | - Jonasz B. Patkowski
- Department of Life Sciences, Centre for Bacterial Resistance Biology, Imperial College London, London, United Kingdom
| | - Jie E. Yang
- Department of Biochemistry, University of Wisconsin-Madison, Madison, Wisconsin, USA
| | - James Casanova
- Department of Molecular Cell Biology, University of Virginia, Charlottesville, Virginia, USA
| | - Tiago R. D. Costa
- Department of Life Sciences, Centre for Bacterial Resistance Biology, Imperial College London, London, United Kingdom
| | - Elizabeth R. Wright
- Department of Biochemistry, University of Wisconsin-Madison, Madison, Wisconsin, USA
| | - Edward H. Egelman
- Department of Biochemistry and Molecular Genetics, University of Virginia, Charlottesville, Virginia, USA
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13
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Guilvout I, Samsudin F, Huber RG, Bond PJ, Bardiaux B, Francetic O. Membrane platform protein PulF of the Klebsiella type II secretion system forms a trimeric ion channel essential for endopilus assembly and protein secretion. mBio 2024; 15:e0142323. [PMID: 38063437 PMCID: PMC10790770 DOI: 10.1128/mbio.01423-23] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [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: 06/05/2023] [Accepted: 10/24/2023] [Indexed: 01/17/2024] Open
Abstract
IMPORTANCE Type IV pili and type II secretion systems are members of the widespread type IV filament (T4F) superfamily of nanomachines that assemble dynamic and versatile surface fibers in archaea and bacteria. The assembly and retraction of T4 filaments with diverse surface properties and functions require the plasma membrane platform proteins of the GspF/PilC superfamily. Generally considered dimeric, platform proteins are thought to function as passive transmitters of the mechanical energy generated by the ATPase motor, to somehow promote insertion of pilin subunits into the nascent pilus fibers. Here, we generate and experimentally validate structural predictions that support the trimeric state of a platform protein PulF from a type II secretion system. The PulF trimers form selective proton or sodium channels which might energize pilus assembly using the membrane potential. The conservation of the channel sequence and structural features implies a common mechanism for all T4F assembly systems. We propose a model of the oligomeric PulF-PulE ATPase complex that provides an essential framework to investigate and understand the pilus assembly mechanism.
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Affiliation(s)
- Ingrid Guilvout
- Institut Pasteur, Université Paris Cité, CNRS UMR 3528, Biochemistry of Macromolecular Interactions Unit, Paris, France
| | | | | | - Peter J. Bond
- Bioinformatics Institute (A-STAR), Singapore, Singapore
- Department of Biological Sciences, National University of Singapore, Singapore, Singapore
| | - Benjamin Bardiaux
- Institut Pasteur, Université Paris Cité, CNRS UMR 3528, Structural Bioinformatics Unit, Paris, France
- Institut Pasteur, Université Paris Cité, CNRS UMR 3528, Bacterial Transmembrane Systems Unit, Paris, France
| | - Olivera Francetic
- Institut Pasteur, Université Paris Cité, CNRS UMR 3528, Biochemistry of Macromolecular Interactions Unit, Paris, France
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14
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Mom J, Chouikha I, Valette O, Pieulle L, Pelicic V. Systematic functional analysis of the Com pilus in Streptococcus sanguinis: a minimalistic type 4 filament dedicated to DNA uptake in monoderm bacteria. mBio 2024; 15:e0266723. [PMID: 38095871 PMCID: PMC10790768 DOI: 10.1128/mbio.02667-23] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [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: 09/29/2023] [Accepted: 11/07/2023] [Indexed: 01/17/2024] Open
Abstract
IMPORTANCE Type 4 filaments (T4F) are nanomachines ubiquitous in prokaryotes, centered on filamentous polymers of type 4 pilins. T4F are exceptionally versatile and widespread virulence factors in bacterial pathogens. The mechanisms of filament assembly and the many functions they facilitate remain poorly understood because of the complexity of T4F machineries. This hinders the development of anti-T4F drugs. The significance of our research lies in characterizing the simplest known T4F-the Com pilus that mediates DNA uptake in competent monoderm bacteria-and showing that four protein components universally conserved in T4F are sufficient for filament assembly. The Com pilus becomes a model for elucidating the mechanisms of T4F assembly.
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Affiliation(s)
- Jeremy Mom
- Laboratoire de Chimie Bactérienne, Aix-Marseille Université-CNRS (UMR 7283), Institut de Microbiologie de la Méditerranée, Marseille, France
| | - Iman Chouikha
- Laboratoire de Chimie Bactérienne, Aix-Marseille Université-CNRS (UMR 7283), Institut de Microbiologie de la Méditerranée, Marseille, France
| | - Odile Valette
- Laboratoire de Chimie Bactérienne, Aix-Marseille Université-CNRS (UMR 7283), Institut de Microbiologie de la Méditerranée, Marseille, France
| | - Laetitia Pieulle
- Laboratoire de Chimie Bactérienne, Aix-Marseille Université-CNRS (UMR 7283), Institut de Microbiologie de la Méditerranée, Marseille, France
| | - Vladimir Pelicic
- Laboratoire de Chimie Bactérienne, Aix-Marseille Université-CNRS (UMR 7283), Institut de Microbiologie de la Méditerranée, Marseille, France
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15
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Cheung NA, Song M, Sue CK, Clubb RT. Quantifying the Kinetics of Pilus-Specific Sortase-Catalyzed Crosslinking Using High-Performance Liquid Chromatography. Methods Mol Biol 2024; 2727:135-143. [PMID: 37815714 DOI: 10.1007/978-1-0716-3491-2_11] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [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] [Indexed: 10/11/2023]
Abstract
Gram-positive bacteria display pili whose protein components (pilins) are covalently crosslinked by pilus-specific sortase enzymes. These cysteine transpeptidase enzymes catalyze a transpeptidation reaction that joins the pilins together via lysine isopeptide bonds. The crosslinking reaction that builds the SpaA pilus in Corynebacterium diphtheriae is mediated by the SrtA sortase (CdSrtA) and has been reconstituted in vitro. Here, we present a protocol that can be used to measure the kinetics of CdSrtA-catalyzed crosslinking using high-performance liquid chromatography (HPLC). In principle, this biochemical procedure can be used to measure the in vitro crosslinking activity of any pilus-specific sortase.
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Affiliation(s)
- Nicole A Cheung
- UCLA-DOE Institute for Genomics and Proteomics, University of California, Los Angeles, Los Angeles, CA, USA
- Molecular Biology Institute, University of California, Los Angeles, Los Angeles, CA, USA
| | - Mabel Song
- Department of Chemistry and Biochemistry, University of California, Los Angeles, Los Angeles, CA, USA
| | - Christopher K Sue
- Department of Chemistry and Biochemistry, University of California, Los Angeles, Los Angeles, CA, USA
- UCLA-DOE Institute for Genomics and Proteomics, University of California, Los Angeles, Los Angeles, CA, USA
| | - Robert T Clubb
- Department of Chemistry and Biochemistry, University of California, Los Angeles, Los Angeles, CA, USA.
- UCLA-DOE Institute for Genomics and Proteomics, University of California, Los Angeles, Los Angeles, CA, USA.
- Molecular Biology Institute, University of California, Los Angeles, Los Angeles, CA, USA.
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16
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Bhat AH, Das A, Ton-That H. Single-Copy Gene Editing of a Cell Wall-Anchored Pilin in Actinomyces oris. Methods Mol Biol 2024; 2727:125-134. [PMID: 37815713 DOI: 10.1007/978-1-0716-3491-2_10] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [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] [Indexed: 10/11/2023]
Abstract
The Gram-positive bacterium Actinomyces oris expresses a unique cell wall-anchored fimbria comprised of the fimbrial shaft FimA and the tip fimbrillin CafA, whose gene is not genetically linked to the fimA locus, unlike many other fimbrial gene loci in Gram-positive bacteria. Mutational analyses of individual fimbrillins, FimA and CafA, in A. oris often rely on multi-copy plasmids that may alter the stoichiometry of fimbrillins in vivo, hence fimbrial assembly. Here, we provide a robust method for single-copy gene expression and mutagenesis in A. oris, using CafA as an experimental model. This method can be applied for single-copy gene editing in various bacterial systems.
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Affiliation(s)
- Aadil H Bhat
- Division of Oral & Systemic Health Sciences, School of Dentistry, University of California, Los Angeles, CA, USA
| | - Asis Das
- Department of Medicine, Neag Comprehensive Cancer Center, University of Connecticut Health Center, Farmington, CT, USA
| | - Hung Ton-That
- Division of Oral & Systemic Health Sciences, School of Dentistry, University of California, Los Angeles, CA, USA.
- Department of Microbiology, Immunology & Molecular Genetics, University of California, Los Angeles, Los Angeles, CA, USA.
- Molecular Biology Institute, University of California, Los Angeles, CA, USA.
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17
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Tyagi S, Yadav RK, Krishnan V. Determination of the Crystal Structure of the Cell Wall-Anchored Proteins and Pilins. Methods Mol Biol 2024; 2727:159-191. [PMID: 37815717 DOI: 10.1007/978-1-0716-3491-2_14] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/11/2023]
Abstract
Surface proteins and pili (or pilus) anchored on the Gram-positive bacterial cell wall play a vital role in adhesion, colonization, biofilm formation, and immunomodulation. The pilus consists of building blocks called pilins or pilus subunits. The surface proteins and pilins share some common sequences and structural features. They contain an N-terminal signal sequence and the C-terminal cell wall sorting region, enabling their transportation across the membrane and covalent attachment to the bacterial cell wall, respectively. The transpeptidase enzymes called sortases facilitate the covalent links between the pilins during the pilus assembly and between surface proteins or basal subunits of pili and peptidoglycan-bridge during the cell wall anchoring. Thus, elucidating three-dimensional structures for the surface proteins and pilins at the atomic level is essential for understanding the mechanism of adhesion, pilus assembly, and host interaction. This chapter aims to provide a general protocol for crystal structure determination of surface proteins and pilins anchored on the Gram-positive bacterial cell wall and substrates for sortases. The protocol involves the production of recombinant protein, crystallization, and structure determination by X-ray crystallography technique.
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Affiliation(s)
- Shivangi Tyagi
- Laboratory of Structural Biology, Regional Centre for Biotechnology, NCR Biotech Science Cluster, Faridabad, India
| | - Rajnesh Kumari Yadav
- Laboratory of Structural Biology, Regional Centre for Biotechnology, NCR Biotech Science Cluster, Faridabad, India
| | - Vengadesan Krishnan
- Laboratory of Structural Biology, Regional Centre for Biotechnology, NCR Biotech Science Cluster, Faridabad, India.
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18
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Sonani RR, Sanchez JC, Baumgardt JK, Kundra S, Wright ER, Craig L, Egelman EH. Tad and toxin-coregulated pilus structures reveal unexpected diversity in bacterial type IV pili. Proc Natl Acad Sci U S A 2023; 120:e2316668120. [PMID: 38011558 PMCID: PMC10710030 DOI: 10.1073/pnas.2316668120] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [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: 09/25/2023] [Accepted: 10/25/2023] [Indexed: 11/29/2023] Open
Abstract
Type IV pili (T4P) are ubiquitous in both bacteria and archaea. They are polymers of the major pilin protein, which has an extended and protruding N-terminal helix, α1, and a globular C-terminal domain. Cryo-EM structures have revealed key differences between the bacterial and archaeal T4P in their C-terminal domain structure and in the packing and continuity of α1. This segment forms a continuous α-helix in archaeal T4P but is partially melted in all published bacterial T4P structures due to a conserved helix breaking proline at position 22. The tad (tight adhesion) T4P are found in both bacteria and archaea and are thought to have been acquired by bacteria through horizontal transfer from archaea. Tad pilins are unique among the T4 pilins, being only 40 to 60 residues in length and entirely lacking a C-terminal domain. They also lack the Pro22 found in all high-resolution bacterial T4P structures. We show using cryo-EM that the bacterial tad pilus from Caulobacter crescentus is composed of continuous helical subunits that, like the archaeal pilins, lack the melted portion seen in other bacterial T4P and share the packing arrangement of the archaeal T4P. We further show that a bacterial T4P, the Vibrio cholerae toxin coregulated pilus, which lacks Pro22 but is not in the tad family, has a continuous N-terminal α-helix, yet its α1 s are arranged similar to those in other bacterial T4P. Our results highlight the role of Pro22 in helix melting and support an evolutionary relationship between tad and archaeal T4P.
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Affiliation(s)
- Ravi R. Sonani
- Department of Biochemistry and Molecular Genetics, University of Virginia, Charlottesville, VA22903
| | - Juan Carlos Sanchez
- Department of Biochemistry, University of Wisconsin-Madison, Madison, WI53706
| | - Joseph K. Baumgardt
- Department of Biochemistry, University of Wisconsin-Madison, Madison, WI53706
| | - Shivani Kundra
- Department of Molecular Biology and Biochemistry, Simon Fraser University, Burnaby, BCV5A 1S6, Canada
| | - Elizabeth R. Wright
- Department of Biochemistry, University of Wisconsin-Madison, Madison, WI53706
| | - Lisa Craig
- Department of Molecular Biology and Biochemistry, Simon Fraser University, Burnaby, BCV5A 1S6, Canada
| | - Edward H. Egelman
- Department of Biochemistry and Molecular Genetics, University of Virginia, Charlottesville, VA22903
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19
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Luo Y, Zhang J. [Visualization method of type Ⅳ pili and its application in the study of pili function]. Sheng Wu Gong Cheng Xue Bao 2023; 39:4534-4549. [PMID: 38013182 DOI: 10.13345/j.cjb.230082] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 11/29/2023]
Abstract
As an important protein structure on the surface of bacteria, type Ⅳ pili (TFP) is the sensing and moving organ of bacteria. It plays a variety of roles in bacterial physiology, cell adhesion, host cell invasion, DNA uptake, protein secretion, biofilm formation, cell movement and electron transmission. With the rapid development of research methods, technical equipment and pili visualization tools, increasing number of studies have revealed various functions of pili in cellular activities, which greatly facilitated the microbial single cell research. This review focuses on the pili visualization method and its application in the functional research of TFP, providing ideas for the research and application of TFP in biology, medicine and ecology.
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Affiliation(s)
- Yan Luo
- Frontier Science Center for Synthetic Biology and Key Laboratory of Systems Bioengineering (Ministry of Education), School of Chemical Engineering and Technology, Tianjin University, Tianjin 300350, China
| | - Jingchao Zhang
- Medical Genetics Center, Sichuan Provincial People's Hospital, University of Electronic Science and Technology of China, Chengdu 610054, Sichuan, China
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20
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Giese C, Puorger C, Ignatov O, Bečárová Z, Weber ME, Schärer MA, Capitani G, Glockshuber R. Stochastic chain termination in bacterial pilus assembly. Nat Commun 2023; 14:7718. [PMID: 38001074 PMCID: PMC10673952 DOI: 10.1038/s41467-023-43449-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [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: 10/14/2022] [Accepted: 11/09/2023] [Indexed: 11/26/2023] Open
Abstract
Adhesive type 1 pili from uropathogenic Escherichia coli strains are filamentous, supramolecular protein complexes consisting of a short tip fibrillum and a long, helical rod formed by up to several thousand copies of the major pilus subunit FimA. Here, we reconstituted the entire type 1 pilus rod assembly reaction in vitro, using all constituent protein subunits in the presence of the assembly platform FimD, and identified the so-far uncharacterized subunit FimI as an irreversible assembly terminator. We provide a complete, quantitative model of pilus rod assembly kinetics based on the measured rate constants of FimD-catalyzed subunit incorporation. The model reliably predicts the length distribution of assembled pilus rods as a function of the ratio between FimI and the main pilus subunit FimA and is fully consistent with the length distribution of membrane-anchored pili assembled in vivo. The results show that the natural length distribution of adhesive pili formed via the chaperone-usher pathway results from a stochastic chain termination reaction. In addition, we demonstrate that FimI contributes to anchoring the pilus to the outer membrane and report the crystal structures of (i) FimI in complex with the assembly chaperone FimC, (ii) the FimI-FimC complex bound to the N-terminal domain of FimD, and (iii) a ternary complex between FimI, FimA and FimC that provides structural insights on pilus assembly termination and pilus anchoring by FimI.
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Affiliation(s)
- Christoph Giese
- Institute of Molecular Biology and Biophysics, Department of Biology, ETH Zurich, 8093, Zurich, Switzerland.
| | - Chasper Puorger
- Institute of Molecular Biology and Biophysics, Department of Biology, ETH Zurich, 8093, Zurich, Switzerland
- Institute for Chemistry and Bioanalytics, University of Applied Sciences and Arts Northwestern Switzerland, 4132, Muttenz, Switzerland
| | - Oleksandr Ignatov
- Institute of Molecular Biology and Biophysics, Department of Biology, ETH Zurich, 8093, Zurich, Switzerland
- V.I. Grishchenko Clinic of Reproductive Medicine, Blahovishchenska st.25, 61052, Kharkiv, Ukraine
| | - Zuzana Bečárová
- Institute of Molecular Biology and Biophysics, Department of Biology, ETH Zurich, 8093, Zurich, Switzerland
| | - Marco E Weber
- Institute of Molecular Biology and Biophysics, Department of Biology, ETH Zurich, 8093, Zurich, Switzerland
- Laboratory of Physical Chemistry, Department of Chemistry and Applied Biosciences, ETH Zurich, 8093, Zurich, Switzerland
| | - Martin A Schärer
- Institute of Molecular Biology and Biophysics, Department of Biology, ETH Zurich, 8093, Zurich, Switzerland
- Laboratory of Biomolecular Research, Paul Scherrer Institute, 5232, Villigen, Switzerland
| | - Guido Capitani
- Laboratory of Biomolecular Research, Paul Scherrer Institute, 5232, Villigen, Switzerland
| | - Rudi Glockshuber
- Institute of Molecular Biology and Biophysics, Department of Biology, ETH Zurich, 8093, Zurich, Switzerland
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21
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Fulton DA, Dura G, Peters DT. The polymer and materials science of the bacterial fimbriae Caf1. Biomater Sci 2023; 11:7229-7246. [PMID: 37791425 PMCID: PMC10628683 DOI: 10.1039/d3bm01075a] [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] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2023] [Accepted: 09/22/2023] [Indexed: 10/05/2023]
Abstract
Fimbriae are long filamentous polymeric protein structures located upon the surface of bacteria. Often implicated in pathogenicity, the biosynthesis and function of fimbriae has been a productive topic of study for many decades. Evolutionary pressures have ensured that fimbriae possess unique structural and mechanical properties which are advantageous to bacteria. These properties are also difficult to engineer with well-known synthetic and natural fibres, and this has raised an intriguing question: can we exploit the unique properties of bacterial fimbriae in useful ways? Initial work has set out to explore this question by using Capsular antigen fragment 1 (Caf1), a fimbriae expressed naturally by Yersina pestis. These fibres have evolved to 'shield' the bacterium from the immune system of an infected host, and thus are rather bioinert in nature. Caf1 is, however, very amenable to structural mutagenesis which allows the incorporation of useful bioactive functions and the modulation of the fibre's mechanical properties. Its high-yielding recombinant synthesis also ensures plentiful quantities of polymer are available to drive development. These advantageous features make Caf1 an archetype for the development of new polymers and materials based upon bacterial fimbriae. Here, we cover recent advances in this new field, and look to future possibilities of this promising biopolymer.
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Affiliation(s)
- David A Fulton
- Chemistry-School of Natural Science and Environmental Sciences, Newcastle University, Newcastle-upon-Tyne, NE1 7RU, UK.
| | - Gema Dura
- Chemistry-School of Natural Science and Environmental Sciences, Newcastle University, Newcastle-upon-Tyne, NE1 7RU, UK.
- Departamento de Química Inorgánica Orgánica y Bioquímica Universidad de Castilla-La Mancha Facultad de Ciencias y Tecnologías Químicas-IRICAAvda, C. J. Cela, 10, Ciudad Real 13071, Spain
| | - Daniel T Peters
- Biosciences Institute, Medical School, Newcastle University, Newcastle upon Tyne, NE1 7RU, UK
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Herfurth M, Pérez-Burgos M, Søgaard-Andersen L. The mechanism for polar localization of the type IVa pilus machine in Myxococcus xanthus. mBio 2023; 14:e0159323. [PMID: 37754549 PMCID: PMC10653833 DOI: 10.1128/mbio.01593-23] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [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: 06/22/2023] [Accepted: 07/31/2023] [Indexed: 09/28/2023] Open
Abstract
IMPORTANCE Type IVa pili (T4aP) are widespread bacterial cell surface structures with important functions in motility, surface adhesion, biofilm formation, and virulence. Different bacteria have adapted different piliation patterns. To address how these patterns are established, we focused on the bipolar localization of the T4aP machine in the model organism Myxococcus xanthus by studying the localization of the PilQ secretin, the first component of this machine that assembles at the poles. Based on experiments using a combination of fluorescence microscopy, biochemistry, and computational structural analysis, we propose that PilQ, and specifically its AMIN domains, binds septal and polar peptidoglycan, thereby enabling polar Tgl localization, which then stimulates PilQ multimerization in the outer membrane. We also propose that the presence and absence of AMIN domains in T4aP secretins contribute to the different piliation patterns across bacteria.
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Affiliation(s)
- Marco Herfurth
- Department of Ecophysiology, Max Planck Institute for Terrestrial Microbiology, Marburg, Germany
| | - María Pérez-Burgos
- Department of Ecophysiology, Max Planck Institute for Terrestrial Microbiology, Marburg, Germany
| | - Lotte Søgaard-Andersen
- Department of Ecophysiology, Max Planck Institute for Terrestrial Microbiology, Marburg, Germany
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23
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Palalay JJS, Simsek AN, Reed JL, Koch MD, Sabass B, Sanfilippo JE. Shear force enhances adhesion of Pseudomonas aeruginosa by counteracting pilus-driven surface departure. Proc Natl Acad Sci U S A 2023; 120:e2307718120. [PMID: 37788310 PMCID: PMC10576114 DOI: 10.1073/pnas.2307718120] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [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: 05/17/2023] [Accepted: 09/04/2023] [Indexed: 10/05/2023] Open
Abstract
Fluid flow is thought to prevent bacterial adhesion, but some bacteria use adhesins with catch bond properties to enhance adhesion under high shear forces. However, many studies on bacterial adhesion either neglect the influence of shear force or use shear forces that are not typically found in natural systems. In this study, we use microfluidics and single-cell imaging to examine how the human pathogen Pseudomonas aeruginosa interacts with surfaces when exposed to shear forces typically found in the human body (0.1 pN to 10 pN). Through cell tracking, we demonstrate that the angle between the cell and the surface predicts if a cell will depart the surface. We discover that at lower shear forces, type IV pilus retraction tilts cells away from the surface, promoting surface departure. Conversely, we show that higher shear forces counterintuitively enhance adhesion by counteracting type IV pilus retraction-dependent cell tilting. Thus, our results reveal that P. aeruginosa exhibits behavior reminiscent of a catch bond, without having a specific adhesin that is enhanced by force. Instead, P. aeruginosa couples type IV pilus dynamics and cell geometry to tune adhesion to its mechanical environment, which likely provides a benefit in dynamic host environments.
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Affiliation(s)
| | - Ahmet N. Simsek
- Department of Veterinary Sciences, Institute for Infectious Diseases and Zoonoses, Ludwig-Maximilians-Universität München, Munich80752, Germany
| | - Jessie L. Reed
- Department of Biology, Texas A&M University, College Station, TX77843
| | - Matthias D. Koch
- Department of Biology, Texas A&M University, College Station, TX77843
| | - Benedikt Sabass
- Department of Veterinary Sciences, Institute for Infectious Diseases and Zoonoses, Ludwig-Maximilians-Universität München, Munich80752, Germany
| | - Joseph E. Sanfilippo
- Department of Biochemistry, University of Illinois at Urbana-Champaign, Urbana, IL61801
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Riediger M, Hoffmann K, Isberner R, Dreyer A, Tersteegen A, Marquardt P, Kaasch AJ, Zautner AE. Chimaeribacter arupi a new member of the Yersineacea family has the characteristics of a human pathogen. Front Cell Infect Microbiol 2023; 13:1277522. [PMID: 37868348 PMCID: PMC10587679 DOI: 10.3389/fcimb.2023.1277522] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2023] [Accepted: 09/14/2023] [Indexed: 10/24/2023] Open
Abstract
Chimaeribacter arupi (heterotypic synonym: "Nissabacter archeti") is a facultative anaerobic, newly described Gram-negative rod and belongs to the Yersineacea family. Here, we report the case of a 19-month-old female infant patient who presented to the emergency unit with somnolence and fever. C. arupi was isolated from a positive blood culture, taken via an implanted Broviac catheter, proving a bloodstream infection by the pathogen. The objective of this study was to utilize whole genome sequencing to assess the genes encoding potential virulence associated factors, which may play a role in host tropism, tissue invasion and the subsequent stages in the pathogenesis of a bloodstream infection with C. arupi. The genome of the isolate was completely sequenced employing Illumina MiSeq and Nanopore MinION sequencing and the presumptive virulence associated factors and antimicrobial resistance genes were investigated in more detail. Additionally, we performed metabolic profiling and susceptibility testing by microdilution. The presence of predicted TcfC-like α-Pili suggests that C. arupi is highly adapted to humans as a host. It utilizes flagellar and type IV pili-mediated motility, as well as a number of γ1-pili and a σ-pilus, which may be used to facilitate biofilm formation and adherence to host epithelia. Additionally, long polar fimbriae may aid in tissue invasion. The bacterium possesses antioxidant factors, which may enable temporary survival in phagolysosomes, and a capsule that potentially provides protection from phagocytosis. It may acquire iron ions from erythrocytes through the type 6 secretion system and hemolysins. Furthermore, the isolate exhibits beta-lactamase-mediated penicillin and aminopenicillin resistance. Based on the analysis of the whole genome, we conclude that C. arupi possesses virulence factors associated with tissue invasion and may thus be a potential opportunistic pathogen of bloodstream infections.
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Affiliation(s)
- Matthias Riediger
- Institut für Medizinische Mikrobiologie und Krankenhaushygiene, Medizinische Fakultät der Otto-von-Guericke Universität Magdeburg, Magdeburg, Germany
| | - Katharina Hoffmann
- Institut für Medizinische Mikrobiologie und Krankenhaushygiene, Medizinische Fakultät der Otto-von-Guericke Universität Magdeburg, Magdeburg, Germany
| | - Riekje Isberner
- Universitätskinderklinik, Medizinische Fakultät der Otto-von-Guericke Universität Magdeburg, Magdeburg, Germany
| | - Annika Dreyer
- Institut für Medizinische Mikrobiologie und Virologie, Universitätsmedizin Göttingen, Göttingen, Germany
| | - Aljoscha Tersteegen
- Institut für Medizinische Mikrobiologie und Krankenhaushygiene, Medizinische Fakultät der Otto-von-Guericke Universität Magdeburg, Magdeburg, Germany
| | - Pauline Marquardt
- Institut für Medizinische Mikrobiologie und Krankenhaushygiene, Medizinische Fakultät der Otto-von-Guericke Universität Magdeburg, Magdeburg, Germany
| | - Achim J. Kaasch
- Institut für Medizinische Mikrobiologie und Krankenhaushygiene, Medizinische Fakultät der Otto-von-Guericke Universität Magdeburg, Magdeburg, Germany
- Center for Health and Medical Prevention (CHaMP), Center for Health and Medical Prevention, Otto-von-Guericke-University Magdeburg, Magdeburg, Germany
| | - Andreas E. Zautner
- Institut für Medizinische Mikrobiologie und Krankenhaushygiene, Medizinische Fakultät der Otto-von-Guericke Universität Magdeburg, Magdeburg, Germany
- Center for Health and Medical Prevention (CHaMP), Center for Health and Medical Prevention, Otto-von-Guericke-University Magdeburg, Magdeburg, Germany
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25
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Jønsson R, Björling A, Midtgaard SR, Jensen GV, Skar-Gislinge N, Arleth L, Matthews S, Krogfelt KA, Jenssen H. Aggregative adherence fimbriae form compact structures as seen by SAXS. Sci Rep 2023; 13:16516. [PMID: 37783694 PMCID: PMC10545799 DOI: 10.1038/s41598-023-42079-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2023] [Accepted: 09/05/2023] [Indexed: 10/04/2023] Open
Abstract
Bacterial colonization is mediated by fimbriae, which are thin hair-like appendages dispersed from the bacterial surface. The aggregative adherence fimbriae from enteroaggregative E. coli are secreted through the outer membrane and consist of polymerized minor and major pilin subunits. Currently, the understanding of the structural morphology and the role of the minor pilin subunit in the polymerized fimbriae are limited. In this study we use small-angle X-ray scattering to reveal the structural morphology of purified fimbriae in solution. We show that the aggregative fimbriae are compact arrangements of subunit proteins Agg5A + Agg3B which are assembled pairwise on a flexible string rather than extended in relatively straight filaments. Absence of the minor subunit leads to less compact fimbriae, but did not affect the length. The study provides novel insights into the structural morphology and assembly of the aggregative adherence fimbriae. Our study suggests that the minor subunit is not located at the tip of the fimbriae as previously speculated but has a higher importance for the assembled fimbriae by affecting the global structure.
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Affiliation(s)
- Rie Jønsson
- Department of Science and Environment, Roskilde University, 4000, Roskilde, Denmark.
| | | | | | | | | | - Lise Arleth
- Niels Bohr Institute, Universitetsparken 5, 2100, Copenhagen, Denmark
| | - Steve Matthews
- Department of Life Sciences, Centre for Structural Biology, Imperial College London, South Kensington, London, UK
| | | | - Håvard Jenssen
- Department of Science and Environment, Roskilde University, 4000, Roskilde, Denmark.
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26
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Kilb A, Burghard-Schrod M, Holtrup S, Graumann PL. Uptake of environmental DNA in Bacillus subtilis occurs all over the cell surface through a dynamic pilus structure. PLoS Genet 2023; 19:e1010696. [PMID: 37816065 PMCID: PMC10564135 DOI: 10.1371/journal.pgen.1010696] [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] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2023] [Accepted: 08/28/2023] [Indexed: 10/12/2023] Open
Abstract
At the transition to stationary phase, a subpopulation of Bacillus subtilis cells can enter the developmental state of competence, where DNA is taken up through the cell envelope, and is processed to single stranded DNA, which is incorporated into the genome if sufficient homology between sequences exists. We show here that the initial step of transport across the cell wall occurs via a true pilus structure, with an average length of about 500 nm, which assembles at various places on the cell surface. Once assembled, the pilus remains at one position and can be retracted in a time frame of seconds. The major pilin, ComGC, was studied at a single molecule level in live cells. ComGC was found in two distinct populations, one that would correspond to ComGC freely diffusing throughout the cell membrane, and one that is relatively stationary, likely reflecting pilus-incorporated molecules. The ratio of 65% diffusing and 35% stationary ComGC molecules changed towards more stationary molecules upon addition of external DNA, while the number of pili in the population did not strongly increase. These findings suggest that the pilus assembles stochastically, but engages more pilin monomers from the membrane fraction in the presence of transport substrate. Our data support a model in which transport of environmental DNA occurs through the entire cell surface by a dynamic pilus, mediating efficient uptake through the cell wall into the periplasm, where DNA diffuses to a cell pole containing the localized transport machinery mediating passage into the cytosol.
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Affiliation(s)
- Alexandra Kilb
- Fachbereich Chemie und Zentrum für Synthetische Mikrobiologie, SYNMIKRO, Philipps-Universität Marburg, Marburg, Germany
| | - Marie Burghard-Schrod
- Fachbereich Chemie und Zentrum für Synthetische Mikrobiologie, SYNMIKRO, Philipps-Universität Marburg, Marburg, Germany
| | - Sven Holtrup
- Fachbereich Chemie und Zentrum für Synthetische Mikrobiologie, SYNMIKRO, Philipps-Universität Marburg, Marburg, Germany
| | - Peter L. Graumann
- Fachbereich Chemie und Zentrum für Synthetische Mikrobiologie, SYNMIKRO, Philipps-Universität Marburg, Marburg, Germany
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27
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Miao C, Cui Y, Yan Z, Jiang Y. Pilus of Streptococcus pneumoniae: structure, function and vaccine potential. Front Cell Infect Microbiol 2023; 13:1270848. [PMID: 37799336 PMCID: PMC10548224 DOI: 10.3389/fcimb.2023.1270848] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2023] [Accepted: 09/04/2023] [Indexed: 10/07/2023] Open
Abstract
The pilus is an extracellular structural part that can be detected in some Streptococcus pneumoniae (S. pneumoniae) isolates (type I pili are found in approximately 30% of strains, while type II pili are found in approximately 20%). It is anchored to the cell wall by LPXTG-like motifs on the peptidoglycan. Two kinds of pili have been discovered, namely, pilus-1 and pilus-2. The former is encoded by pilus islet 1 (PI-1) and is a polymer formed by the protein subunits RrgA, RrgB and RrgC. The latter is encoded by pilus islet 2 (PI-2) and is a polymer composed mainly of the structural protein PitB. Although pili are not necessary for the survival of S. pneumoniae, they serve as the structural basis and as virulence factors that mediate the adhesion of bacteria to host cells and play a direct role in promoting the adhesion, colonization and pathogenesis of S. pneumoniae. In addition, as candidate antigens for protein vaccines, pili have promising potential for use in vaccines with combined immunization strategies. Given the current understanding of the pili of S. pneumoniae regarding the genes, proteins, structure, biological function and epidemiological relationship with serotypes, combined with the immunoprotective efficacy of pilins as protein candidates for vaccines, we here systematically describe the research status and prospects of S. pneumoniae pili and provide new ideas for subsequent vaccine research and development.
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Affiliation(s)
- Chenglin Miao
- Department of Laboratory Medicine, West China Second University Hospital, Sichuan University, Chengdu, Sichuan, China
| | - Yali Cui
- Department of Laboratory Medicine, West China Second University Hospital, Sichuan University, Chengdu, Sichuan, China
- Department of Laboratory Medicine, Meishan Women and Children’s Hospital, Alliance Hospital of West China Second University Hospital, Sichuan University, Meishan, Sichuan, China
- Department of Laboratory Medicine, West China Second University Hospital (Tianfu), Sichuan University/Sichuan Provincial Children’s Hospital, Meishan, Sichuan, China
| | - Ziyi Yan
- Department of Laboratory Medicine, West China Second University Hospital, Sichuan University, Chengdu, Sichuan, China
| | - Yongmei Jiang
- Department of Laboratory Medicine, West China Second University Hospital, Sichuan University, Chengdu, Sichuan, China
- Key Laboratory of Birth Defects and Related Diseases of Women and Children (Sichuan University), Ministry of Education, Chengdu, Sichuan, China
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28
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Matczak S, Bouchez V, Leroux P, Douché T, Collinet N, Landier A, Gianetto QG, Guillot S, Chamot-Rooke J, Hasan M, Matondo M, Brisse S, Toubiana J. Biological differences between FIM2 and FIM3 fimbriae of Bordetella pertussis: not just the serotype. Microbes Infect 2023; 25:105152. [PMID: 37245862 DOI: 10.1016/j.micinf.2023.105152] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2023] [Revised: 05/17/2023] [Accepted: 05/19/2023] [Indexed: 05/30/2023]
Abstract
INTRODUCTION Bordetella pertussis still circulates worldwide despite vaccination. Fimbriae are components of some acellular pertussis vaccines. Population fluctuations of B. pertussis fimbrial serotypes (FIM2 and FIM3) are observed, and fim3 alleles (fim3-1 [clade 1] and fim3-2 [clade 2]) mark a major phylogenetic subdivision of B. pertussis. OBJECTIVES To compare microbiological characteristics and expressed protein profiles between fimbrial serotypes FIM2 and FIM3 and genomic clades. METHODS A total of 19 isolates were selected. Absolute protein abundance of the main virulence factors, autoagglutination and biofilm formation, bacterial survival in whole blood, induced blood cell cytokine secretion, and global proteome profiles were assessed. RESULTS Compared to FIM3, FIM2 isolates produced more fimbriae, less cellular pertussis toxin subunit 1 and more biofilm, but auto-agglutinated less. FIM2 isolates had a lower survival rate in cord blood, but induced higher levels of IL-4, IL-8 and IL-1β secretion. Global proteome comparisons uncovered 15 differentially produced proteins between FIM2 and FIM3 isolates, involved in adhesion and metabolism of metals. FIM3 isolates of clade 2 produced more FIM3 and more biofilm compared to clade 1. CONCLUSION FIM serotype and fim3 clades are associated with proteomic and other biological differences, which may have implications on pathogenesis and epidemiological emergence.
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Affiliation(s)
- Soraya Matczak
- Institut Pasteur, Université Paris Cité, Biodiversity and Epidemiology of Bacterial Pathogens, 28, Rue Du Docteur Roux, 75015, Paris, France
| | - Valérie Bouchez
- Institut Pasteur, Université Paris Cité, Biodiversity and Epidemiology of Bacterial Pathogens, 28, Rue Du Docteur Roux, 75015, Paris, France; National Reference Center for Whooping Cough and Other Bordetella Infections, Institut Pasteur, 28, Rue Du Docteur Roux, 75015, Paris, France
| | - Pauline Leroux
- Institut Pasteur, Université Paris Cité, Biodiversity and Epidemiology of Bacterial Pathogens, 28, Rue Du Docteur Roux, 75015, Paris, France
| | - Thibaut Douché
- Institut Pasteur, Université Paris Cité, CNRS UAR2024, Proteomics Platform, Mass Spectrometry for Biology Unit, 28, Rue Du Docteur Roux, 75015, Paris, France
| | - Nils Collinet
- Institut Pasteur, Université Paris Cité, Biodiversity and Epidemiology of Bacterial Pathogens, 28, Rue Du Docteur Roux, 75015, Paris, France
| | - Annie Landier
- Institut Pasteur, Université Paris Cité, Biodiversity and Epidemiology of Bacterial Pathogens, 28, Rue Du Docteur Roux, 75015, Paris, France; National Reference Center for Whooping Cough and Other Bordetella Infections, Institut Pasteur, 28, Rue Du Docteur Roux, 75015, Paris, France
| | - Quentin Giai Gianetto
- Institut Pasteur, Université Paris Cité, CNRS UAR2024, Proteomics Platform, Mass Spectrometry for Biology Unit, 28, Rue Du Docteur Roux, 75015, Paris, France; Institut Pasteur, Université Paris Cité, Bioinformatics and Biostatistics Hub, 28, Rue Du Docteur Roux, 75015, Paris, France
| | - Sophie Guillot
- Institut Pasteur, Université Paris Cité, Biodiversity and Epidemiology of Bacterial Pathogens, 28, Rue Du Docteur Roux, 75015, Paris, France; National Reference Center for Whooping Cough and Other Bordetella Infections, Institut Pasteur, 28, Rue Du Docteur Roux, 75015, Paris, France
| | - Julia Chamot-Rooke
- Institut Pasteur, Université Paris Cité, CNRS UAR2024, Proteomics Platform, Mass Spectrometry for Biology Unit, 28, Rue Du Docteur Roux, 75015, Paris, France
| | - Milena Hasan
- Institut Pasteur, Université Paris Cité, Cytometry and Biomarkers Unit of Technology and Service (CB UTechS), 28, Rue Du Docteur Roux, 75015, Paris, France
| | - Mariette Matondo
- Institut Pasteur, Université Paris Cité, CNRS UAR2024, Proteomics Platform, Mass Spectrometry for Biology Unit, 28, Rue Du Docteur Roux, 75015, Paris, France
| | - Sylvain Brisse
- Institut Pasteur, Université Paris Cité, Biodiversity and Epidemiology of Bacterial Pathogens, 28, Rue Du Docteur Roux, 75015, Paris, France; National Reference Center for Whooping Cough and Other Bordetella Infections, Institut Pasteur, 28, Rue Du Docteur Roux, 75015, Paris, France
| | - Julie Toubiana
- Institut Pasteur, Université Paris Cité, Biodiversity and Epidemiology of Bacterial Pathogens, 28, Rue Du Docteur Roux, 75015, Paris, France; National Reference Center for Whooping Cough and Other Bordetella Infections, Institut Pasteur, 28, Rue Du Docteur Roux, 75015, Paris, France; Department of General Pediatrics and Pediatric Infectious Diseases, Hôpital Necker-Enfants Malades, APHP, Université Paris Cité, 149, Rue de Sèvres, 75015, Paris, France.
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29
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Odermatt PD, Nussbaum P, Monnappa S, Talà L, Li Z, Sivabalasarma S, Albers SV, Persat A. Archaeal type IV pili stabilize Haloferax volcanii biofilms in flow. Curr Biol 2023; 33:3265-3271.e4. [PMID: 37473762 DOI: 10.1016/j.cub.2023.06.055] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2023] [Revised: 05/01/2023] [Accepted: 06/20/2023] [Indexed: 07/22/2023]
Abstract
Multicellular communities of contiguous cells attached to solid surfaces called biofilms represent a common microbial strategy to improve resilience in adverse environments.1,2,3 While bacterial biofilms have been under intense investigation, whether archaeal biofilms follow similar assembly rules remains unknown.4,5Haloferax volcanii is an extremely halophilic euryarchaeon that commonly colonizes salt crust surfaces. H. volcanii produces long and thin appendages called type IV pili (T4Ps). These play a role in surface attachment and biofilm formation in both archaea and bacteria. In this study, we employed biophysical experiments to identify the function of T4Ps in H. volcanii biofilm morphogenesis. H. volcanii expresses not one but six types of major pilin subunits that are predicted to compose T4Ps. Non-invasive imaging of T4Ps in live cells using interferometric scattering (iSCAT) microscopy reveals that piliation varies across mutants expressing single major pilin isoforms. T4Ps are necessary to secure attachment of single cells to surfaces, and the adhesive strength of pilin mutants correlates with their level of piliation. In flow, H. volcanii forms clonal biofilms that extend in three dimensions. Notably, the expression of PilA2, a single pilin isoform, is sufficient to maintain levels of piliation, surface attachment, and biofilm formation that are indistinguishable from the wild type. Furthermore, we discovered that fluid flow stabilizes biofilm integrity; as in the absence of flow, biofilms tend to lose cohesion and disperse in a density-dependent manner. Overall, our results demonstrate that T4P-surface and possibly T4P-T4P interactions promote biofilm formation and integrity and that flow is a key factor regulating archaeal biofilm formation.
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Affiliation(s)
- Pascal D Odermatt
- Global Health Institute and Institute for Bioengineering, School of Life Sciences, EPFL, 1015 Lausanne, Switzerland
| | - Phillip Nussbaum
- Molecular Biology of Archaea, Faculty of Biology, University of Freiburg, 79104 Freiburg, Germany
| | - Sourabh Monnappa
- Global Health Institute and Institute for Bioengineering, School of Life Sciences, EPFL, 1015 Lausanne, Switzerland
| | - Lorenzo Talà
- Global Health Institute and Institute for Bioengineering, School of Life Sciences, EPFL, 1015 Lausanne, Switzerland
| | - Zhengqun Li
- Molecular Biology of Archaea, Faculty of Biology, University of Freiburg, 79104 Freiburg, Germany
| | - Shamphavi Sivabalasarma
- Molecular Biology of Archaea, Faculty of Biology, University of Freiburg, 79104 Freiburg, Germany
| | - Sonja-Verena Albers
- Molecular Biology of Archaea, Faculty of Biology, University of Freiburg, 79104 Freiburg, Germany.
| | - Alexandre Persat
- Global Health Institute and Institute for Bioengineering, School of Life Sciences, EPFL, 1015 Lausanne, Switzerland.
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30
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Geiger CJ, O’Toole GA. Evidence for the Type IV Pilus Retraction Motor PilT as a Component of the Surface Sensing System in Pseudomonas aeruginosa. J Bacteriol 2023; 205:e0017923. [PMID: 37382531 PMCID: PMC10367593 DOI: 10.1128/jb.00179-23] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [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: 06/05/2023] [Accepted: 06/07/2023] [Indexed: 06/30/2023] Open
Abstract
Biofilm formation begins when bacteria contacting a surface induce cellular changes to become better adapted for surface growth. One of the first changes to occur for Pseudomonas aeruginosa after surface contact is an increase in the nucleotide second messenger 3',5'-cyclic AMP (cAMP). It has been demonstrated that this increase in intracellular cAMP is dependent on functional type IV pili (T4P) relaying a signal to the Pil-Chp system, but the mechanism by which this signal is transduced remains poorly understood. Here, we investigate the role of the type IV pilus retraction motor PilT in sensing a surface and relaying that signal to cAMP production. We show that mutations in PilT, and in particular those impacting the ATPase activity of this motor protein, reduce surface-dependent cAMP production. We identify a novel interaction between PilT and PilJ, a member of the Pil-Chp system, and propose a new model whereby P. aeruginosa uses its PilT retraction motor to sense a surface and to relay that signal via PilJ to increased production of cAMP. We discuss these findings in light of current T4P-dependent surface sensing models for P. aeruginosa. IMPORTANCE T4P are cellular appendages that allow P. aeruginosa to sense a surface, leading to the production of cAMP. This second messenger not only activates virulence pathways but leads to further surface adaptation and irreversible attachment of cells. Here, we demonstrate the importance of the retraction motor PilT in surface sensing. We also present a new surface sensing model in P. aeruginosa whereby the T4P retraction motor PilT senses and transmits the surface signal, likely via its ATPase domain and interaction with PilJ, to mediate production of the second messenger cAMP.
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Affiliation(s)
- C. J. Geiger
- Department of Microbiology and Immunology, Geisel School of Medicine at Dartmouth, Hanover, New Hampshire, USA
| | - G. A. O’Toole
- Department of Microbiology and Immunology, Geisel School of Medicine at Dartmouth, Hanover, New Hampshire, USA
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31
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Risser DD. Hormogonium Development and Motility in Filamentous Cyanobacteria. Appl Environ Microbiol 2023; 89:e0039223. [PMID: 37199640 PMCID: PMC10304961 DOI: 10.1128/aem.00392-23] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/19/2023] Open
Abstract
Filamentous cyanobacteria exhibit some of the greatest developmental complexity observed in the prokaryotic domain. This includes the ability to differentiate nitrogen-fixing cells known as heterocysts, spore-like akinetes, and hormogonia, which are specialized motile filaments capable of gliding on solid surfaces. Hormogonia and motility play critical roles in several aspects of the biology of filamentous cyanobacteria, including dispersal, phototaxis, the formation of supracellular structures, and the establishment of nitrogen-fixing symbioses with plants. While heterocyst development has been investigated extensively at the molecular level, much less is known about akinete or hormogonium development and motility. This is due, in part, to the loss of developmental complexity during prolonged laboratory culture in commonly employed model filamentous cyanobacteria. In this review, recent progress in understanding the molecular level regulation of hormogonium development and motility in filamentous cyanobacteria is discussed, with a focus on experiments performed using the genetically tractable model filamentous cyanobacterium Nostoc punctiforme, which retains the developmental complexity of field isolates.
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Affiliation(s)
- Douglas D. Risser
- Department of Biology, University of Colorado Colorado Springs, Colorado Springs, Colorado, USA
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Nguyen M, Wu TH, Danielson K, Khan N, Zhang J, Craig L. Mechanism of secretion of TcpF by the Vibrio cholerae toxin-coregulated pilus. Proc Natl Acad Sci U S A 2023; 120:e2212664120. [PMID: 37040409 PMCID: PMC10120004 DOI: 10.1073/pnas.2212664120] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [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: 07/25/2022] [Accepted: 02/28/2023] [Indexed: 04/12/2023] Open
Abstract
Many bacteria possess dynamic filaments called Type IV pili (T4P) that perform diverse functions in colonization and dissemination, including host cell adhesion, DNA uptake, and secretion of protein substrates-exoproteins-from the periplasm to the extracellular space. The Vibrio cholerae toxin-coregulated pilus (TCP) and the enterotoxigenic Escherichia coli CFA/III pilus each mediates export of a single exoprotein, TcpF and CofJ, respectively. Here, we show that the disordered N-terminal segment of mature TcpF is the export signal (ES) recognized by TCP. Deletion of the ES disrupts secretion and causes TcpF to accumulate in the V. cholerae periplasm. The ES alone can mediate export of Neisseria gonorrhoeae FbpA by V. cholerae in a T4P-dependent manner. The ES is specific for its autologous T4P machinery as CofJ bearing the TcpF ES is exported by V. cholerae, whereas TcpF bearing the CofJ ES is not. Specificity is mediated by binding of the ES to TcpB, a minor pilin that primes pilus assembly and forms a trimer at the pilus tip. Finally, the ES is proteolyzed from the mature TcpF protein upon secretion. Together, these results provide a mechanism for delivery of TcpF across the outer membrane and release into the extracellular space.
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Affiliation(s)
- Minh Nguyen
- Department of Molecular Biology and Biochemistry, Simon Fraser University, Burnaby, BCV5A 1S6, Canada
| | - Tzu-Hui Wu
- Department of Molecular Biology and Biochemistry, Simon Fraser University, Burnaby, BCV5A 1S6, Canada
| | - Katie J. Danielson
- Department of Molecular Biology and Biochemistry, Simon Fraser University, Burnaby, BCV5A 1S6, Canada
| | - Nabeel M. Khan
- Department of Molecular Biology and Biochemistry, Simon Fraser University, Burnaby, BCV5A 1S6, Canada
| | - John Zhijia Zhang
- Department of Molecular Biology and Biochemistry, Simon Fraser University, Burnaby, BCV5A 1S6, Canada
| | - Lisa Craig
- Department of Molecular Biology and Biochemistry, Simon Fraser University, Burnaby, BCV5A 1S6, Canada
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Böhning J, Dobbelstein AW, Sulkowski N, Eilers K, von Kügelgen A, Tarafder AK, Peak-Chew SY, Skehel M, Alva V, Filloux A, Bharat TAM. Architecture of the biofilm-associated archaic Chaperone-Usher pilus CupE from Pseudomonas aeruginosa. PLoS Pathog 2023; 19:e1011177. [PMID: 37058467 PMCID: PMC10104325 DOI: 10.1371/journal.ppat.1011177] [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] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2022] [Accepted: 02/03/2023] [Indexed: 04/15/2023] Open
Abstract
Chaperone-Usher Pathway (CUP) pili are major adhesins in Gram-negative bacteria, mediating bacterial adherence to biotic and abiotic surfaces. While classical CUP pili have been extensively characterized, little is known about so-called archaic CUP pili, which are phylogenetically widespread and promote biofilm formation by several human pathogens. In this study, we present the electron cryomicroscopy structure of the archaic CupE pilus from the opportunistic human pathogen Pseudomonas aeruginosa. We show that CupE1 subunits within the pilus are arranged in a zigzag architecture, containing an N-terminal donor β-strand extending from each subunit into the next, where it is anchored by hydrophobic interactions, with comparatively weaker interactions at the rest of the inter-subunit interface. Imaging CupE pili on the surface of P. aeruginosa cells using electron cryotomography shows that CupE pili adopt variable curvatures in response to their environment, which might facilitate their role in promoting cellular attachment. Finally, bioinformatic analysis shows the widespread abundance of cupE genes in isolates of P. aeruginosa and the co-occurrence of cupE with other cup clusters, suggesting interdependence of cup pili in regulating bacterial adherence within biofilms. Taken together, our study provides insights into the architecture of archaic CUP pili, providing a structural basis for understanding their role in promoting cellular adhesion and biofilm formation in P. aeruginosa.
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Affiliation(s)
- Jan Böhning
- Sir William Dunn School of Pathology, University of Oxford, Oxford, United Kingdom
| | - Adrian W. Dobbelstein
- Department of Protein Evolution, Max Planck Institute for Biology Tübingen, Tübingen, Germany
| | - Nina Sulkowski
- Sir William Dunn School of Pathology, University of Oxford, Oxford, United Kingdom
| | - Kira Eilers
- Department of Life Sciences, MRC Centre for Molecular Bacteriology and Infection, Imperial College London, London, United Kingdom
| | - Andriko von Kügelgen
- Sir William Dunn School of Pathology, University of Oxford, Oxford, United Kingdom
| | - Abul K. Tarafder
- Sir William Dunn School of Pathology, University of Oxford, Oxford, United Kingdom
| | - Sew-Yeu Peak-Chew
- Cell Biology Division, MRC Laboratory of Molecular Biology, Francis Crick Avenue, Cambridge, United Kingdom
| | - Mark Skehel
- Proteomics Science Technology Platform, The Francis Crick Institute, London, United Kingdom
| | - Vikram Alva
- Department of Protein Evolution, Max Planck Institute for Biology Tübingen, Tübingen, Germany
| | - Alain Filloux
- Department of Life Sciences, MRC Centre for Molecular Bacteriology and Infection, Imperial College London, London, United Kingdom
| | - Tanmay A. M. Bharat
- Sir William Dunn School of Pathology, University of Oxford, Oxford, United Kingdom
- Structural Studies Division, MRC Laboratory of Molecular Biology, Francis Crick Avenue, Cambridge, United Kingdom
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34
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Volle C, Núñez ME, Spain EM, Hart BC, Wengen MB, Lane S, Criollo A, Mahoney CA, Ferguson MA. AFM Force Mapping Elucidates Pilus Deployment and Key Lifestyle-Dependent Surface Properties in Bdellovibrio bacteriovorus. Langmuir 2023; 39:4233-4244. [PMID: 36926913 PMCID: PMC10062353 DOI: 10.1021/acs.langmuir.2c03134] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/17/2022] [Revised: 03/03/2023] [Indexed: 06/18/2023]
Abstract
Bdellovibrio bacteriovorus is known for predation of a wide variety of Gram-negative bacteria, making it of interest as an alternative or supplement to chemical antibiotics. However, a fraction of B. bacteriovorus follows a nonpredatory, "host-independent" (HI) life cycle. In this study, live predatory and HI B. bacteriovorus were captured on a surface and examined, in buffer, by collecting force maps using atomic force microscopy (AFM). The approach curves obtained on HI cells are similar to those on other Gram-negative cells, with a short nonlinear region followed by a linear region. In contrast, the approach curves obtained on predatory cells have a large nonlinear region, reflecting the unusual flexibility of the predatory cell. As the AFM tip is retracted, it shows virtually no adhesion to predatory B. bacteriovorus but has multiple adhesion events on HI cells and the 200-500+ nm region immediately surrounding them. Measured pull-off forces, pull-off distances, and effective spring constants are consistent with the multiple stretching events of Type IV pili, both on and especially adjacent to the cells. Exposure of the HI B. bacteriovorus to a pH-neutral 10% cranberry juice solution, which contains type A proanthocyanidins that are known to interfere with the adhesion of multiple types of pili, results in a substantial reduction in adhesion. Type IV pili are required for successful predation by B. bacteriovorus, but pili used in the predation process are located at the non-flagellated pole of the cell and can retract when not in use. Such pili are rarely observed under the conditions of this study, where the predator has not encountered a prey cell. In contrast, HI cells appear to have many pili distributed on and around the whole cell, presumably ready to be utilized for a variety of HI cell activities including attachment to surfaces.
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Affiliation(s)
- Catherine
B. Volle
- Departments
of Chemistry and Biology, Cornell College, Mount Vernon, Iowa 52314, United States
| | - Megan E. Núñez
- Department
of Chemistry, Wellesley College, Wellesley, Massachusetts 02481, United States
| | - Eileen M. Spain
- Department
of Chemistry, Occidental College, Los Angeles, California 90041, United States
| | - Bridget C. Hart
- Department
of Chemistry, State University of New York, New Paltz, New York 12561, United States
| | - Michael B. Wengen
- Department
of Chemistry, State University of New York, New Paltz, New York 12561, United States
| | - Sophia Lane
- Department
of Chemistry, State University of New York, New Paltz, New York 12561, United States
| | - Alexa Criollo
- Department
of Chemistry, State University of New York, New Paltz, New York 12561, United States
| | - Catherine A. Mahoney
- Department
of Chemistry, State University of New York, New Paltz, New York 12561, United States
| | - Megan A. Ferguson
- Department
of Chemistry, State University of New York, New Paltz, New York 12561, United States
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Merfa MV, Zhu X, Shantharaj D, Gomez LM, Naranjo E, Potnis N, Cobine PA, De La Fuente L. Complete functional analysis of type IV pilus components of a reemergent plant pathogen reveals neofunctionalization of paralog genes. PLoS Pathog 2023; 19:e1011154. [PMID: 36780566 PMCID: PMC9956873 DOI: 10.1371/journal.ppat.1011154] [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] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2022] [Revised: 02/24/2023] [Accepted: 01/26/2023] [Indexed: 02/15/2023] Open
Abstract
Type IV pilus (TFP) is a multifunctional bacterial structure involved in twitching motility, adhesion, biofilm formation, as well as natural competence. Here, by site-directed mutagenesis and functional analysis, we determined the phenotype conferred by each of the 38 genes known to be required for TFP biosynthesis and regulation in the reemergent plant pathogenic fastidious prokaryote Xylella fastidiosa. This pathogen infects > 650 plant species and causes devastating diseases worldwide in olives, grapes, blueberries, and almonds, among others. This xylem-limited, insect-transmitted pathogen lives constantly under flow conditions and therefore is highly dependent on TFP for host colonization. In addition, TFP-mediated natural transformation is a process that impacts genomic diversity and environmental fitness. Phenotypic characterization of the mutants showed that ten genes were essential for both movement and natural competence. Interestingly, seven sets of paralogs exist, and mutations showed opposing phenotypes, indicating evolutionary neofunctionalization of subunits within TFP. The minor pilin FimT3 was the only protein exclusively required for natural competence. By combining approaches of molecular microbiology, structural biology, and biochemistry, we determined that the minor pilin FimT3 (but not the other two FimT paralogs) is the DNA receptor in TFP of X. fastidiosa and constitutes an example of neofunctionalization. FimT3 is conserved among X. fastidiosa strains and binds DNA non-specifically via an electropositive surface identified by homolog modeling. This protein surface includes two arginine residues that were exchanged with alanine and shown to be involved in DNA binding. Among plant pathogens, fimT3 was found in ~ 10% of the available genomes of the plant associated Xanthomonadaceae family, which are yet to be assessed for natural competence (besides X. fastidiosa). Overall, we highlight here the complex regulation of TFP in X. fastidiosa, providing a blueprint to understand TFP in other bacteria living under flow conditions.
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Affiliation(s)
- Marcus V. Merfa
- Department of Entomology and Plant Pathology, Auburn University, Auburn, Alabama, United States of America
| | - Xinyu Zhu
- Department of Biological Sciences, Auburn University, Auburn, Alabama, United States of America
| | - Deepak Shantharaj
- Department of Entomology and Plant Pathology, Auburn University, Auburn, Alabama, United States of America
| | - Laura M. Gomez
- Department of Entomology and Plant Pathology, Auburn University, Auburn, Alabama, United States of America
| | - Eber Naranjo
- Department of Entomology and Plant Pathology, Auburn University, Auburn, Alabama, United States of America
| | - Neha Potnis
- Department of Entomology and Plant Pathology, Auburn University, Auburn, Alabama, United States of America
| | - Paul A. Cobine
- Department of Biological Sciences, Auburn University, Auburn, Alabama, United States of America
| | - Leonardo De La Fuente
- Department of Entomology and Plant Pathology, Auburn University, Auburn, Alabama, United States of America
- * E-mail:
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Nakane D. Live Cell Imaging of the Twitching Motility of Cyanobacteria by High-Resolution Microscopy. Methods Mol Biol 2023; 2646:255-263. [PMID: 36842120 DOI: 10.1007/978-1-0716-3060-0_20] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/28/2023]
Abstract
Many cyanobacteria show directional movement either toward or away from light sources. The cell movement, also known as twitching motility, is usually driven by type IV pili (T4P), a bacterial molecular machine. The machine generates a propulsion force through repeated cycles of extension and retraction of pilus filaments. Here, I describe a phototaxis assay for observing Synechocystis sp. PCC6803 and Thermosynechococcus vulcanus at the single-cell level with optical microscopy. By adding fluorescent beads, I also describe a method how to visualize the asymmetric activation of T4P during phototaxis.
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Affiliation(s)
- Daisuke Nakane
- Department of Engineering Science, Graduate School of Informatics and Engineering, The University of Electro-Communications, Tokyo, Japan.
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37
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Gahlot DK, Taheri N, MacIntyre S. Diversity in Genetic Regulation of Bacterial Fimbriae Assembled by the Chaperone Usher Pathway. Int J Mol Sci 2022; 24:ijms24010161. [PMID: 36613605 PMCID: PMC9820224 DOI: 10.3390/ijms24010161] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2022] [Revised: 11/09/2022] [Accepted: 11/10/2022] [Indexed: 12/24/2022] Open
Abstract
Bacteria express different types of hair-like proteinaceous appendages on their cell surface known as pili or fimbriae. These filamentous structures are primarily involved in the adherence of bacteria to both abiotic and biotic surfaces for biofilm formation and/or virulence of non-pathogenic and pathogenic bacteria. In pathogenic bacteria, especially Gram-negative bacteria, fimbriae play a key role in bacteria-host interactions which are critical for bacterial invasion and infection. Fimbriae assembled by the Chaperone Usher pathway (CUP) are widespread within the Enterobacteriaceae, and their expression is tightly regulated by specific environmental stimuli. Genes essential for expression of CUP fimbriae are organised in small blocks/clusters, which are often located in proximity to other virulence genes on a pathogenicity island. Since these surface appendages play a crucial role in bacterial virulence, they have potential to be harnessed in vaccine development. This review covers the regulation of expression of CUP-assembled fimbriae in Gram-negative bacteria and uses selected examples to demonstrate both dedicated and global regulatory mechanisms.
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Affiliation(s)
- Dharmender K. Gahlot
- School of Biological Sciences, University of Reading, Reading RG6 6EX, UK
- Department of Molecular Biology, Umeå University, 901 87 Umeå, Sweden
- Umeå Centre for Microbial Research (UCMR), Umeå University, 901 87 Umeå, Sweden
- Correspondence: (D.K.G.); (S.M.)
| | - Nayyer Taheri
- APC Microbiome Institute, University College Cork, T12 K8AF Cork, Ireland
| | - Sheila MacIntyre
- School of Biological Sciences, University of Reading, Reading RG6 6EX, UK
- Correspondence: (D.K.G.); (S.M.)
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38
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Yin L, Dai Y, Chen H, He X, Ouyang P, Huang X, Sun X, Ai Y, Lai S, Zhu L, Xu Z. Cinnamaldehyde Resist Salmonella Typhimurium Adhesion by Inhibiting Type I Fimbriae. Molecules 2022; 27:molecules27227753. [PMID: 36431853 PMCID: PMC9699031 DOI: 10.3390/molecules27227753] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2022] [Revised: 10/29/2022] [Accepted: 10/31/2022] [Indexed: 11/12/2022] Open
Abstract
Salmonella Typhimurium (S. Typhimurium), a common foodborne pathogen, severely harms the public and food security. Type I fimbriae (T1F) of S. Typhimurium, plays a crucial role in the pathogenic processes; it mediates the adhesion of bacteria to the mannose receptor on the host cell, assists the bacteria to invade the host cell, and triggers an inflammatory response. Cinnamaldehyde is the main ingredient in cinnamon essential oil. In this study, cinnamaldehyde was demonstrated to inhibit the expression of T1F by hemagglutination inhibition test, transmission electron microscopy, and biofilms. The mechanism of cinnamaldehyde action was studied by proteomics technology, PCR and Western blotting. The results showed that cinnamaldehyde can inhibit T1F in S. typhimurium without the growth of bacteria, by regulating the level of expression and transcription of fimA, fimZ, fimY, fimH and fimW. Proteomics results showed that cinnamaldehyde downregulated the subunits and regulators of T1F. In addition, the invasion assays proved that cinnamaldehyde can indeed reduce the ability of S. typhimurium to adhere to cells. The results of animal experiments showed that the colonization in the intestinal tract and the expression levels of inflammatory cytokine were significantly decreased, and the intestinal mucosal immune factors MUC1 and MUC2 were increased under cinnamaldehyde treatment. Therefore, cinnamaldehyde may be a potential drug to target T1F to treat Salmonella infections.
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Affiliation(s)
- Lizi Yin
- College of Veterinary Medicine, Sichuan Agriculture University, Huimin Road 211, Chengdu 611130, China
| | - Yuyun Dai
- College of Veterinary Medicine, Sichuan Agriculture University, Huimin Road 211, Chengdu 611130, China
| | - Han Chen
- College of Veterinary Medicine, Sichuan Agriculture University, Huimin Road 211, Chengdu 611130, China
| | - Xuewen He
- College of Veterinary Medicine, Sichuan Agriculture University, Huimin Road 211, Chengdu 611130, China
| | - Ping Ouyang
- College of Veterinary Medicine, Sichuan Agriculture University, Huimin Road 211, Chengdu 611130, China
| | - Xiaoli Huang
- College of Animal Science and Technology, Sichuan Agriculture University, Huimin Road 211, Chengdu 611130, China
| | - Xiangang Sun
- College of Veterinary Medicine, Sichuan Agriculture University, Huimin Road 211, Chengdu 611130, China
| | - Yanru Ai
- College of Veterinary Medicine, Sichuan Agriculture University, Huimin Road 211, Chengdu 611130, China
| | - Siyuan Lai
- College of Veterinary Medicine, Sichuan Agriculture University, Huimin Road 211, Chengdu 611130, China
| | - Ling Zhu
- College of Veterinary Medicine, Sichuan Agriculture University, Huimin Road 211, Chengdu 611130, China
| | - Zhiwen Xu
- College of Veterinary Medicine, Sichuan Agriculture University, Huimin Road 211, Chengdu 611130, China
- Correspondence: ; Tel.: +86-13981604765
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39
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Ronish LA, Sidner B, Yu Y, Piepenbrink KH. Recognition of extracellular DNA by type IV pili promotes biofilm formation by Clostridioides difficile. J Biol Chem 2022; 298:102449. [PMID: 36064001 PMCID: PMC9556784 DOI: 10.1016/j.jbc.2022.102449] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [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: 01/20/2022] [Revised: 08/25/2022] [Accepted: 08/26/2022] [Indexed: 11/15/2022] Open
Abstract
Clostridioides difficile is a Gram-positive bacillus, which is a frequent cause of gastrointestinal infections triggered by the depletion of the gut microbiome. Because of the frequent recurrence of these infections after antibiotic treatment, mechanisms of C. difficile persistence and recurrence, including biofilm formation, are of increasing interest. Previously, our group and others found that type IV pili, filamentous helical appendages polymerized from protein subunits, promoted microcolony and biofilm formation in C. difficile. In Gram-negative bacteria, the ability of type IV pili to mediate bacterial self-association has been explained through interactions between the pili of adjacent cells, but type IV pili from several Gram-negative species are also required for natural competence through DNA uptake. Here, we report the ability of two C. difficile pilin subunits, PilJ and PilW, to bind to DNA in vitro, as well as the defects in biofilm formation in the pilJ and pilW gene-interruption mutants. Additionally, we have resolved the X-ray crystal structure of PilW, which we use to model possible structural mechanisms for the formation of C. difficile biofilm through interactions between type IV pili and the DNA of the extracellular matrix. Taken together, our results provide further insight into the relationship between type IV pilus function and biofilm formation in C. difficile and, more broadly, suggest that DNA recognition by type IV pili and related structures may have functional importance beyond DNA uptake for natural competence.
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Affiliation(s)
- Leslie A Ronish
- Department of Biochemistry, University of Nebraska-Lincoln, Lincoln, Nebraska, USA
| | - Ben Sidner
- Department of Food Science and Technology, University of Nebraska-Lincoln, Lincoln, Nebraska, USA
| | - Yafan Yu
- Department of Biochemistry, University of Nebraska-Lincoln, Lincoln, Nebraska, USA; Department of Food Science and Technology, University of Nebraska-Lincoln, Lincoln, Nebraska, USA
| | - Kurt H Piepenbrink
- Department of Biochemistry, University of Nebraska-Lincoln, Lincoln, Nebraska, USA; Department of Food Science and Technology, University of Nebraska-Lincoln, Lincoln, Nebraska, USA; Department of Chemistry, University of Nebraska-Lincoln, Lincoln, Nebraska, USA; Nebraska Food for Health Center, University of Nebraska-Lincoln, Lincoln, Nebraska, USA; Center for Integrated Biomolecular Communication, University of Nebraska-Lincoln, Lincoln, Nebraska, USA.
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40
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Alteri CJ, Rios-Sarabia N, De la Cruz MA, González-y-Merchand JA, Soria-Bustos J, Maldonado-Bernal C, Cedillo ML, Yáñez-Santos JA, Martínez-Laguna Y, Torres J, Friedman RL, Girón JA, Ares MA. The Flp type IV pilus operon of Mycobacterium tuberculosis is expressed upon interaction with macrophages and alveolar epithelial cells. Front Cell Infect Microbiol 2022; 12:916247. [PMID: 36204636 PMCID: PMC9531140 DOI: 10.3389/fcimb.2022.916247] [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] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2022] [Accepted: 08/29/2022] [Indexed: 11/13/2022] Open
Abstract
The genome of Mycobacterium tuberculosis (Mtb) harbors the genetic machinery for assembly of the Fimbrial low-molecular-weight protein (Flp) type IV pilus. Presumably, the Flp pilus is essential for pathogenesis. However, it remains unclear whether the pili genes are transcribed in culture or during infection of host cells. This study aimed to shed light on the expression of the Flp pili-assembly genes (tadZ, tadA, tadB, tadC, flp, tadE, and tadF) in Mtb growing under different growth conditions (exponential phase, stationary phase, and dormancy NRP1 and NRP2 phases induced by hypoxia), during biofilm formation, and in contact with macrophages and alveolar epithelial cells. We found that expression of tad/flp genes was significantly higher in the stationary phase than in exponential or NRP1 or NRP2 phases suggesting that the bacteria do not require type IV pili during dormancy. Elevated gene expression levels were recorded when the bacilli were in contact for 4 h with macrophages or epithelial cells, compared to mycobacteria propagated alone in the cultured medium. An antibody raised against a 12-mer peptide derived from the Flp pilin subunit detected the presence of Flp pili on intra- and extracellular bacteria infecting eukaryotic cells. Altogether, these are compelling data showing that the Flp pili genes are expressed during the interaction of Mtb with host cells and highlight a role for Flp pili in colonization and invasion of the host, subsequently promoting bacterial survival during dormancy.
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Affiliation(s)
- Christopher J. Alteri
- Department of Natural Sciences, University of Michigan-Dearborn, Dearborn, MI, United States
| | - Nora Rios-Sarabia
- Unidad de Investigación Médica en Enfermedades Infecciosas y Parasitarias, Hospital de Pediatría, Centro Médico Nacional Siglo XXI, Instituto Mexicano del Seguro Social, Mexico City, Mexico
| | - Miguel A. De la Cruz
- Unidad de Investigación Médica en Enfermedades Infecciosas y Parasitarias, Hospital de Pediatría, Centro Médico Nacional Siglo XXI, Instituto Mexicano del Seguro Social, Mexico City, Mexico
| | - Jorge A. González-y-Merchand
- Departamento de Microbiología, Escuela Nacional de Ciencias Biológicas, Instituto Politécnico Nacional, Mexico City, Mexico
| | - Jorge Soria-Bustos
- Instituto de Ciencias de la Salud, Universidad Autónoma del Estado de Hidalgo, Hidalgo, Mexico
| | - Carmen Maldonado-Bernal
- Laboratorio de Investigación en Inmunología y Proteómica, Hospital Infantil de México Federico Gómez, Mexico City, Mexico
| | - María L. Cedillo
- Centro de Detección Biomolecular, Benemérita Universidad Autónoma de Puebla, Puebla, Mexico
| | - Jorge A. Yáñez-Santos
- Centro de Detección Biomolecular, Benemérita Universidad Autónoma de Puebla, Puebla, Mexico
| | - Ygnacio Martínez-Laguna
- Centro de Investigación en Ciencias Microbiológicas, Benemérita Universidad Autónoma de Puebla, Puebla, Mexico
| | - Javier Torres
- Unidad de Investigación Médica en Enfermedades Infecciosas y Parasitarias, Hospital de Pediatría, Centro Médico Nacional Siglo XXI, Instituto Mexicano del Seguro Social, Mexico City, Mexico
| | - Richard L. Friedman
- Department of Immunobiology, University of Arizona, Tucson, AZ, United States
| | - Jorge A. Girón
- Centro de Detección Biomolecular, Benemérita Universidad Autónoma de Puebla, Puebla, Mexico
- *Correspondence: Miguel A. Ares, ; Jorge A. Girón,
| | - Miguel A. Ares
- Unidad de Investigación Médica en Enfermedades Infecciosas y Parasitarias, Hospital de Pediatría, Centro Médico Nacional Siglo XXI, Instituto Mexicano del Seguro Social, Mexico City, Mexico
- Departamento de Microbiología, Escuela Nacional de Ciencias Biológicas, Instituto Politécnico Nacional, Mexico City, Mexico
- *Correspondence: Miguel A. Ares, ; Jorge A. Girón,
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41
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Mondal R, Saldaña-Ahuactzi Z, Soria-Bustos J, Schultz A, Yañez-Santos JA, Laguna YM, Cedillo-Ramírez ML, Girón JA. The EcpD Tip Adhesin of the Escherichia coli Common Pilus Mediates Binding of Enteropathogenic E. coli to Extracellular Matrix Proteins. Int J Mol Sci 2022; 23:ijms231810350. [PMID: 36142263 PMCID: PMC9499635 DOI: 10.3390/ijms231810350] [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] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2022] [Revised: 08/04/2022] [Accepted: 08/30/2022] [Indexed: 11/16/2022] Open
Abstract
The attachment of enteropathogenic Escherichia coli (EPEC) to intestinal epithelial cells is facilitated by several adhesins; however, the individual host-cell receptors for pili-mediated adherence have not been fully characterized. In this study, we evaluated the hypothesis that the E. coli common pilus (ECP) tip adhesin protein EcpD mediates attachment of EPEC to several extracellular matrix (ECM) glycoproteins (fibronectin, laminin, collagens I and IV, and mucin). We found that the ΔecpA mutant, which lacks production of the EcpA filament but retains EcpD on the surface, adhered to these glycoproteins below the wild-type levels, while the ΔecpD mutant, which does not display EcpA or EcpD, bound significantly less to these host glycoproteins. In agreement, a purified recombinant EcpD subunit bound significantly more than EcpA to laminin, fibronectin, collagens I and IV, and mucin in a dose-dependent manner. These are compelling data that strongly suggest that ECP-producing EPEC may bind to host ECM glycoproteins and mucins through the tip adhesin protein EcpD. This study highlights the versatility of EPEC to bind to different host proteins and suggests that the interaction of ECP with the host’s ECM glycoproteins may facilitate colonization of the intestinal mucosal epithelium.
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Affiliation(s)
- Rajesh Mondal
- ICMR-Bhopal Memorial Hospital and Research Center, Bhopal 462038, India
| | - Zeus Saldaña-Ahuactzi
- Paul G. Allen School for Global Health, College of Veterinary Medicine, Washington State University, Pullman, WA 99164, USA
| | - Jorge Soria-Bustos
- Facultad de Medicina Mexicali, Universidad Autónoma de Baja California, Mexicali 21100, Mexico
| | - Andrew Schultz
- Department of Microbiology and Molecular Genetics, University of Florida, Gainesville, FL 32611, USA
| | - Jorge A. Yañez-Santos
- Facultad de Estomatología, Benemérita Universidad Autónoma de Puebla, Puebla 72592, Mexico
| | - Ygnacio Martínez Laguna
- Centro de Investigación en Ciencias Microbiológicas, Benemérita Universidad Autónoma de Puebla, Puebla 72592, Mexico
| | - María L. Cedillo-Ramírez
- Centro de Detección Biomolecular, Benemérita Universidad Autónoma de Puebla, Puebla 72592, Mexico
| | - Jorge A. Girón
- Centro de Detección Biomolecular, Benemérita Universidad Autónoma de Puebla, Puebla 72592, Mexico
- Correspondence:
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Pakharukova N, Malmi H, Tuittila M, Dahlberg T, Ghosal D, Chang YW, Myint SL, Paavilainen S, Knight SD, Lamminmäki U, Uhlin BE, Andersson M, Jensen G, Zavialov AV. Archaic chaperone-usher pili self-secrete into superelastic zigzag springs. Nature 2022; 609:335-340. [PMID: 35853476 PMCID: PMC9452303 DOI: 10.1038/s41586-022-05095-0] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [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: 09/24/2021] [Accepted: 07/08/2022] [Indexed: 11/23/2022]
Abstract
Adhesive pili assembled through the chaperone-usher pathway are hair-like appendages that mediate host tissue colonization and biofilm formation of Gram-negative bacteria1-3. Archaic chaperone-usher pathway pili, the most diverse and widespread chaperone-usher pathway adhesins, are promising vaccine and drug targets owing to their prevalence in the most troublesome multidrug-resistant pathogens1,4,5. However, their architecture and assembly-secretion process remain unknown. Here, we present the cryo-electron microscopy structure of the prototypical archaic Csu pilus that mediates biofilm formation of Acinetobacter baumannii-a notorious multidrug-resistant nosocomial pathogen. In contrast to the thick helical tubes of the classical type 1 and P pili, archaic pili assemble into an ultrathin zigzag architecture secured by an elegant clinch mechanism. The molecular clinch provides the pilus with high mechanical stability as well as superelasticity, a property observed for the first time, to our knowledge, in biomolecules, while enabling a more economical and faster pilus production. Furthermore, we demonstrate that clinch formation at the cell surface drives pilus secretion through the outer membrane. These findings suggest that clinch-formation inhibitors might represent a new strategy to fight multidrug-resistant bacterial infections.
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Affiliation(s)
- Natalia Pakharukova
- Joint Biotechnology Laboratory, MediCity, Faculty of Medicine, University of Turku, Turku, Finland
| | - Henri Malmi
- Joint Biotechnology Laboratory, MediCity, Faculty of Medicine, University of Turku, Turku, Finland
| | - Minna Tuittila
- Joint Biotechnology Laboratory, MediCity, Faculty of Medicine, University of Turku, Turku, Finland
| | - Tobias Dahlberg
- Department of Physics, Umeå Centre for Microbial Research (UCMR), Umeå University, Umeå, Sweden
| | - Debnath Ghosal
- Division of Biology and Biological Engineering, California Institute of Technology, Pasadena, CA, USA
- Division of Medicine, Dentistry and Health Sciences, University of Melbourne, Parkville, Victoria, Australia
| | - Yi-Wei Chang
- Division of Biology and Biological Engineering, California Institute of Technology, Pasadena, CA, USA
- Department of Biochemistry and Biophysics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Si Lhyam Myint
- Department of Molecular Biology, The Laboratory for Molecular Infection Medicine Sweden (MIMS), Umeå Centre for Microbial Research (UCMR), Umeå University, Umeå, Sweden
| | - Sari Paavilainen
- Joint Biotechnology Laboratory, MediCity, Faculty of Medicine, University of Turku, Turku, Finland
| | - Stefan David Knight
- Department of Cell and Molecular Biology, Biomedical Centre, Uppsala University, Uppsala, Sweden
| | - Urpo Lamminmäki
- Department of Life Technologies, University of Turku, Turku, Finland
| | - Bernt Eric Uhlin
- Department of Molecular Biology, The Laboratory for Molecular Infection Medicine Sweden (MIMS), Umeå Centre for Microbial Research (UCMR), Umeå University, Umeå, Sweden
| | - Magnus Andersson
- Department of Physics, Umeå Centre for Microbial Research (UCMR), Umeå University, Umeå, Sweden
| | - Grant Jensen
- Division of Biology and Biological Engineering, California Institute of Technology, Pasadena, CA, USA
| | - Anton V Zavialov
- Joint Biotechnology Laboratory, MediCity, Faculty of Medicine, University of Turku, Turku, Finland.
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Patil PD, Jin Y, Luk YY. Chemical control over Asialo-GM1: A dual ligand for pili and Lectin A that activates swarming motility and facilitates adherence of Pseudomonas aeruginosa. Colloids Surf B Biointerfaces 2022; 215:112478. [PMID: 35390596 DOI: 10.1016/j.colsurfb.2022.112478] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2022] [Revised: 03/14/2022] [Accepted: 03/21/2022] [Indexed: 11/20/2022]
Abstract
Glycolipid, ganglio-N-tetraosylceramide (asialo-GM1), on the mammalian cells are known to be recognized by type IV pili of Pseudomonas aeruginosa. In this work, we show that asialo-GM1 can also be recognized by Lectin A (LecA), another adhesin protein of the P. aeruginosa, by a fluorescent polarization assay, a label-free bacterial motility enabled binding assay, and bacterial mutant studies. On hydrated semi-solid gel surfaces, asialo-GM1 enables swarming and twitching motilities, while on solid surfaces facilitates the bacterial adherence of P. aeruginosa. These results indicate that asialo-GM1 can modulate bioactivities, adherence, and motilities, that are controlled by opposite signaling pathways. We demonstrate that when a solution of pilin monomers or LecA proteins are spread on hydrated gel surfaces, the asialo-GM1 mediated swarming motility is inhibited. Treatment of artificial liposomes containing asialo-GM1 as a component of lipid bilayer with pilin monomers or LecA proteins caused transient leakage of encapsulated dye from liposomes. These results suggest that pili and LecA proteins not only bind to asialo-GM1 but can also cause asialo-GM1 mediated leakage. We also show that both pili and LecA mutants of P. aeruginosa adhere to asialo-GM1 coated solid surfaces, and that a class of synthetic ligands for pili and LecA inhibits both pili and LecA-mediated adherence of P. aeruginosa on asialo-GM1-coated surfaces.
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Affiliation(s)
- Pankaj D Patil
- Department of Chemistry, Syracuse University 1-014 Center of Science and Technology, Syracuse, NY 13244, USA
| | - Yuchen Jin
- Department of Chemistry, Syracuse University 1-014 Center of Science and Technology, Syracuse, NY 13244, USA
| | - Yan-Yeung Luk
- Department of Chemistry, Syracuse University 1-014 Center of Science and Technology, Syracuse, NY 13244, USA.
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Hadjineophytou C, Anonsen JH, Svingerud T, Mortimer TD, Grad YH, Scott NE, Koomey M. Sculpting the Bacterial O-Glycoproteome: Functional Analyses of Orthologous Oligosaccharyltransferases with Diverse Targeting Specificities. mBio 2022; 13:e0379721. [PMID: 35471082 PMCID: PMC9239064 DOI: 10.1128/mbio.03797-21] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [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: 01/05/2022] [Accepted: 03/25/2022] [Indexed: 11/24/2022] Open
Abstract
Protein glycosylation systems are widely recognized in bacteria, including members of the genus Neisseria. In most bacterial species, the molecular mechanisms and evolutionary contexts underpinning target protein selection and the glycan repertoire remain poorly understood. Broad-spectrum O-linked protein glycosylation occurs in all human-associated species groups within the genus Neisseria, but knowledge of their individual glycoprotein repertoires is limited. Interestingly, PilE, the pilin subunit of the type IV pilus (Tfp) colonization factor, is glycosylated in Neisseria gonorrhoeae and Neisseria meningitidis but not in the deeply branching species N. elongata subsp. glycolytica. To examine this in more detail, we assessed PilE glycosylation status across the genus and found that PilEs of commensal clade species are not modified by the gonococcal PglO oligosaccharyltransferase. Experiments using PglO oligosaccharyltransferases from across the genus expressed in N. gonorrhoeae showed that although all were capable of broad-spectrum protein glycosylation, those from a deep-branching group of commensals were unable to support resident PilE glycosylation. Further glycoproteomic analyses of these strains using immunoblotting and mass spectrometry revealed other proteins differentially targeted by otherwise remarkably similar oligosaccharyltransferases. Finally, we generated pglO allelic chimeras that begin to localize PglO protein domains associated with unique substrate targeting activities. These findings reveal previously unappreciated differences within the protein glycosylation systems of highly related bacterial species. We propose that the natural diversity manifest in the neisserial protein substrates and oligosaccharyltransferases has significant potential to inform the structure-function relationships operating in these and related bacterial protein glycosylation systems. IMPORTANCE Although general protein glycosylation systems have been well recognized in prokaryotes, the processes governing their distribution, function, and evolution remain poorly understood. Here, we have begun to address these gaps in knowledge by comparative analyses of broad-spectrum O-linked protein glycosylation manifest in species within the genus Neisseria that strictly colonize humans. Using N. gonorrhoeae as a well-defined model organism in conjunction with comparative genomics, intraspecies gene complementation, and glycoprotein phenotyping, we discovered clear differences in both glycosylation susceptibilities and enzymatic targeting activities of otherwise largely conserved proteins. These findings reveal previously unappreciated differences within the protein glycosylation systems of highly related bacterial species. We propose that the natural diversity manifest within Neisseria species has significant potential to elucidate the structure-function relationships operating in these and related systems and to inform novel approaches to applied glycoengineering strategies.
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Affiliation(s)
- Chris Hadjineophytou
- Department of Biosciences, Section for Genetics and Evolutionary Biology, University of Oslo, Oslo, Norway
| | - Jan Haug Anonsen
- Department of Biosciences, Section for Genetics and Evolutionary Biology, University of Oslo, Oslo, Norway
| | - Tina Svingerud
- Department of Biosciences, Section for Genetics and Evolutionary Biology, University of Oslo, Oslo, Norway
| | - Tatum D. Mortimer
- Department of Immunology and Infectious Diseases, Harvard T. H. Chan School of Public Health, Boston, Massachusetts, USA
| | - Yonatan H. Grad
- Department of Immunology and Infectious Diseases, Harvard T. H. Chan School of Public Health, Boston, Massachusetts, USA
- Division of Infectious Diseases, Brigham and Women’s Hospital and Harvard Medical School, Boston, Massachusetts, USA
| | - Nichollas E. Scott
- Department of Microbiology and Immunology, University of Melbourne at the Peter Doherty Institute for Infection and Immunity, Melbourne, Australia
| | - Michael Koomey
- Department of Biosciences, Section for Genetics and Evolutionary Biology, University of Oslo, Oslo, Norway
- Department of Biosciences, Centre for Ecological and Evolutionary Synthesis, University of Oslo, Oslo, Norway
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Hancock SJ, Lo AW, Ve T, Day CJ, Tan L, Mendez AA, Phan MD, Nhu NTK, Peters KM, Richards AC, Fleming BA, Chang C, Ngu DHY, Forde BM, Haselhorst T, Goh KGK, Beatson SA, Jennings MP, Mulvey MA, Kobe B, Schembri MA. Ucl fimbriae regulation and glycan receptor specificity contribute to gut colonisation by extra-intestinal pathogenic Escherichia coli. PLoS Pathog 2022; 18:e1010582. [PMID: 35700218 PMCID: PMC9236248 DOI: 10.1371/journal.ppat.1010582] [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] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2021] [Revised: 06/27/2022] [Accepted: 05/09/2022] [Indexed: 11/25/2022] Open
Abstract
Extra-intestinal pathogenic Escherichia coli (ExPEC) belong to a critical priority group of antibiotic resistant pathogens. ExPEC establish gut reservoirs that seed infection of the urinary tract and bloodstream, but the mechanisms of gut colonisation remain to be properly understood. Ucl fimbriae are attachment organelles that facilitate ExPEC adherence. Here, we investigated cellular receptors for Ucl fimbriae and Ucl expression to define molecular mechanisms of Ucl-mediated ExPEC colonisation of the gut. We demonstrate differential expression of Ucl fimbriae in ExPEC sequence types associated with disseminated infection. Genome editing of strains from two common sequence types, F11 (ST127) and UTI89 (ST95), identified a single nucleotide polymorphism in the ucl promoter that changes fimbriae expression via activation by the global stress-response regulator OxyR, leading to altered gut colonisation. Structure-function analysis of the Ucl fimbriae tip-adhesin (UclD) identified high-affinity glycan receptor targets, with highest affinity for sialyllacto-N-fucopentose VI, a structure likely to be expressed on the gut epithelium. Comparison of the UclD adhesin to the homologous UcaD tip-adhesin from Proteus mirabilis revealed that although they possess a similar tertiary structure, apart from lacto-N-fucopentose VI that bound to both adhesins at low-micromolar affinity, they recognize different fucose- and glucose-containing oligosaccharides. Competitive surface plasmon resonance analysis together with co-structural investigation of UcaD in complex with monosaccharides revealed a broad-specificity glycan binding pocket shared between UcaD and UclD that could accommodate these interactions. Overall, our study describes a mechanism of adaptation that augments establishment of an ExPEC gut reservoir to seed disseminated infections, providing a pathway for the development of targeted anti-adhesion therapeutics. ExPEC infection of the urinary tract and bloodstream is frequently seeded from an intestinal reservoir, necessitating an understanding of the mechanisms that promote gut colonisation. Here we employed molecular and structural approaches to define the regulation and function of ExPEC Ucl fimbriae as a gut colonisation factor. We describe how mutations in the non-coding regulatory region of the ucl promoter cause increased Ucl fimbriae expression and promote enhanced gut colonisation via tuned induction by a global regulator that senses oxygen stress. We further define the glycan receptor targets of Ucl fimbriae and characterise the structural features of the Ucl adhesin that facilitate these interactions. These findings explain how ExPEC can adapt to survival in the gut to seed extra-intestinal infection.
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Affiliation(s)
- Steven J. Hancock
- School of Chemistry and Molecular Biosciences, The University of Queensland, Brisbane, Queensland, Australia
- Australian Infectious Diseases Research Centre, The University of Queensland, Brisbane, Queensland, Australia
| | - Alvin W. Lo
- School of Chemistry and Molecular Biosciences, The University of Queensland, Brisbane, Queensland, Australia
- Australian Infectious Diseases Research Centre, The University of Queensland, Brisbane, Queensland, Australia
| | - Thomas Ve
- School of Chemistry and Molecular Biosciences, The University of Queensland, Brisbane, Queensland, Australia
- Institute for Glycomics, Griffith University Gold Coast Campus, Gold Coast, Queensland, Australia
| | - Christopher J. Day
- Institute for Glycomics, Griffith University Gold Coast Campus, Gold Coast, Queensland, Australia
| | - Lendl Tan
- School of Chemistry and Molecular Biosciences, The University of Queensland, Brisbane, Queensland, Australia
- Australian Infectious Diseases Research Centre, The University of Queensland, Brisbane, Queensland, Australia
| | - Alejandra A. Mendez
- Division of Microbiology and Immunology, Department of Pathology, University of Utah School of Medicine, Salt Lake City, Utah, United States of America
| | - Minh-Duy Phan
- School of Chemistry and Molecular Biosciences, The University of Queensland, Brisbane, Queensland, Australia
- Australian Infectious Diseases Research Centre, The University of Queensland, Brisbane, Queensland, Australia
| | - Nguyen Thi Khanh Nhu
- School of Chemistry and Molecular Biosciences, The University of Queensland, Brisbane, Queensland, Australia
- Australian Infectious Diseases Research Centre, The University of Queensland, Brisbane, Queensland, Australia
| | - Kate M. Peters
- School of Chemistry and Molecular Biosciences, The University of Queensland, Brisbane, Queensland, Australia
- Australian Infectious Diseases Research Centre, The University of Queensland, Brisbane, Queensland, Australia
| | - Amanda C. Richards
- Division of Microbiology and Immunology, Department of Pathology, University of Utah School of Medicine, Salt Lake City, Utah, United States of America
| | - Brittany A. Fleming
- Division of Microbiology and Immunology, Department of Pathology, University of Utah School of Medicine, Salt Lake City, Utah, United States of America
| | - Chyden Chang
- School of Chemistry and Molecular Biosciences, The University of Queensland, Brisbane, Queensland, Australia
- Australian Infectious Diseases Research Centre, The University of Queensland, Brisbane, Queensland, Australia
| | - Dalton H. Y. Ngu
- School of Chemistry and Molecular Biosciences, The University of Queensland, Brisbane, Queensland, Australia
- Australian Infectious Diseases Research Centre, The University of Queensland, Brisbane, Queensland, Australia
| | - Brian M. Forde
- School of Chemistry and Molecular Biosciences, The University of Queensland, Brisbane, Queensland, Australia
- Australian Infectious Diseases Research Centre, The University of Queensland, Brisbane, Queensland, Australia
| | - Thomas Haselhorst
- Institute for Glycomics, Griffith University Gold Coast Campus, Gold Coast, Queensland, Australia
| | - Kelvin G. K. Goh
- School of Chemistry and Molecular Biosciences, The University of Queensland, Brisbane, Queensland, Australia
- Australian Infectious Diseases Research Centre, The University of Queensland, Brisbane, Queensland, Australia
| | - Scott A. Beatson
- School of Chemistry and Molecular Biosciences, The University of Queensland, Brisbane, Queensland, Australia
- Australian Infectious Diseases Research Centre, The University of Queensland, Brisbane, Queensland, Australia
| | - Michael P. Jennings
- Institute for Glycomics, Griffith University Gold Coast Campus, Gold Coast, Queensland, Australia
| | - Matthew A. Mulvey
- Division of Microbiology and Immunology, Department of Pathology, University of Utah School of Medicine, Salt Lake City, Utah, United States of America
| | - Bostjan Kobe
- School of Chemistry and Molecular Biosciences, The University of Queensland, Brisbane, Queensland, Australia
- Australian Infectious Diseases Research Centre, The University of Queensland, Brisbane, Queensland, Australia
- Institute for Molecular Bioscience, The University of Queensland, Brisbane, Queensland, Australia
| | - Mark A. Schembri
- School of Chemistry and Molecular Biosciences, The University of Queensland, Brisbane, Queensland, Australia
- Australian Infectious Diseases Research Centre, The University of Queensland, Brisbane, Queensland, Australia
- * E-mail:
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46
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Dahlberg T, Baker JL, Bullitt E, Andersson M. Unveiling molecular interactions that stabilize bacterial adhesion pili. Biophys J 2022; 121:2096-2106. [PMID: 35491503 PMCID: PMC9247471 DOI: 10.1016/j.bpj.2022.04.036] [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] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2022] [Revised: 03/09/2022] [Accepted: 04/27/2022] [Indexed: 11/29/2022] Open
Abstract
Adhesion pili assembled by the chaperone-usher pathway are superelastic helical filaments on the surface of bacteria, optimized for attachment to target cells. Here, we investigate the biophysical function and structural interactions that stabilize P pili from uropathogenic bacteria. Using optical tweezers, we measure P pilus subunit-subunit interaction dynamics and show that pilus compliance is contour-length dependent. Atomic details of subunit-subunit interactions of pili under tension are shown using steered molecular dynamics (sMD) simulations. sMD results also indicate that the N-terminal "staple" region of P pili, which provides interactions with pilins that are four and five subunits away, significantly stabilizes the helical filament structure. These data are consistent with previous structural data, and suggest that more layer-to-layer interactions could compensate for the lack of a staple in type 1 pili. This study informs our understanding of essential structural and dynamic features of adhesion pili, supporting the hypothesis that the function of pili is critically dependent on their structure and biophysical properties.
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Affiliation(s)
| | - Joseph L Baker
- Department of Chemistry, The College of New Jersey, Ewing, New Jersey
| | - Esther Bullitt
- Department of Physiology & Biophysics, Boston University School of Medicine, Boston, Massachusetts.
| | - Magnus Andersson
- Department of Physics, Umeå University, Umeå, Sweden; Umeå Centre for Microbial Research (UCMR), Umeå, Sweden.
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Lewis KA, Vermilyea DM, Webster SS, Geiger CJ, de Anda J, Wong GCL, O’Toole GA, Hogan DA. Nonmotile Subpopulations of Pseudomonas aeruginosa Repress Flagellar Motility in Motile Cells through a Type IV Pilus- and Pel-Dependent Mechanism. J Bacteriol 2022; 204:e0052821. [PMID: 35377166 PMCID: PMC9112919 DOI: 10.1128/jb.00528-21] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [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: 10/20/2021] [Accepted: 03/05/2022] [Indexed: 01/03/2023] Open
Abstract
The downregulation of Pseudomonas aeruginosa flagellar motility is a key event in biofilm formation, host colonization, and the formation of microbial communities, but the external factors that repress motility are not well understood. Here, we report that on soft agar, swarming motility can be repressed by cells that are nonmotile due to the absence of a flagellum or flagellar rotation. Mutants that lack either flagellum biosynthesis or rotation, when present at as little as 5% of the total population, suppressed swarming of wild-type cells. Non-swarming cells required functional type IV pili and the ability to produce Pel exopolysaccharide to suppress swarming by the flagellated wild type. Flagellated cells required only type IV pili, but not Pel production, for their swarming to be repressed by non-flagellated cells. We hypothesize that interactions between motile and nonmotile cells may enhance the formation of sessile communities, including those involving multiple genotypes, phenotypically diverse cells, and perhaps other species. IMPORTANCE Our study shows that, under the conditions tested, a small population of non-swarming cells can impact the motility behavior of a larger population. The interactions that lead to the suppression of swarming motility require type IV pili and a secreted polysaccharide, two factors with known roles in biofilm formation. These data suggest that interactions between motile and nonmotile cells may enhance the transition to sessile growth in populations and promote interactions between cells with different genotypes.
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Affiliation(s)
- Kimberley A. Lewis
- Department of Microbiology and Immunology, Geisel School of Medicine at Dartmouth, Hanover, New Hampshire, USA
| | - Danielle M. Vermilyea
- Department of Microbiology and Immunology, Geisel School of Medicine at Dartmouth, Hanover, New Hampshire, USA
| | - Shanice S. Webster
- Department of Microbiology and Immunology, Geisel School of Medicine at Dartmouth, Hanover, New Hampshire, USA
| | - Christopher J. Geiger
- Department of Microbiology and Immunology, Geisel School of Medicine at Dartmouth, Hanover, New Hampshire, USA
| | - Jaime de Anda
- Department of Bioengineering, University of California Los Angeles, Los Angeles, California, USA
- Department of Chemistry and Biochemistry, University of California Los Angeles, Los Angeles, California, USA
- California NanoSystems Institute, University of California Los Angeles, Los Angeles, California, USA
| | - Gerard C. L. Wong
- Department of Bioengineering, University of California Los Angeles, Los Angeles, California, USA
- Department of Chemistry and Biochemistry, University of California Los Angeles, Los Angeles, California, USA
- California NanoSystems Institute, University of California Los Angeles, Los Angeles, California, USA
| | - George A. O’Toole
- Department of Microbiology and Immunology, Geisel School of Medicine at Dartmouth, Hanover, New Hampshire, USA
| | - Deborah A. Hogan
- Department of Microbiology and Immunology, Geisel School of Medicine at Dartmouth, Hanover, New Hampshire, USA
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48
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Sacharok AL, Porsch EA, Yount TA, Keenan O, St. Geme JW. Kingella kingae PilC1 and PilC2 are adhesive multifunctional proteins that promote bacterial adherence, twitching motility, DNA transformation, and pilus biogenesis. PLoS Pathog 2022; 18:e1010440. [PMID: 35353876 PMCID: PMC9000118 DOI: 10.1371/journal.ppat.1010440] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2021] [Revised: 04/11/2022] [Accepted: 03/13/2022] [Indexed: 11/18/2022] Open
Abstract
The gram-negative bacterium Kingella kingae is a leading cause of osteoarticular infections in young children and initiates infection by colonizing the oropharynx. Adherence to respiratory epithelial cells represents an initial step in the process of K. kingae colonization and is mediated in part by type IV pili. In previous work, we observed that elimination of the K. kingae PilC1 and PilC2 pilus-associated proteins resulted in non-piliated organisms that were non-adherent, suggesting that PilC1 and PilC2 have a role in pilus biogenesis. To further define the functions of PilC1 and PilC2, in this study we eliminated the PilT retraction ATPase in the ΔpilC1ΔpilC2 mutant, thereby blocking pilus retraction and restoring piliation. The resulting strain was non-adherent in assays with cultured epithelial cells, supporting the possibility that PilC1 and PilC2 have adhesive activity. Consistent with this conclusion, purified PilC1 and PilC2 were capable of saturable binding to epithelial cells. Additional analysis revealed that PilC1 but not PilC2 also mediated adherence to selected extracellular matrix proteins, underscoring the differential binding specificity of these adhesins. Examination of deletion constructs and purified PilC1 and PilC2 fragments localized adhesive activity to the N-terminal region of both PilC1 and PilC2. The deletion constructs also localized the twitching motility property to the N-terminal region of these proteins. In contrast, the deletion constructs established that the pilus biogenesis function of PilC1 and PilC2 resides in the C-terminal region of these proteins. Taken together, these results provide definitive evidence that PilC1 and PilC2 are adhesins and localize adhesive activity and twitching motility to the N-terminal domain and biogenesis to the C-terminal domain. Kingella kingae is an emerging pediatric pathogen that is a leading cause of osteoarticular infections in children under the age of four. Adherence to epithelial cells is thought to be the first step in K. kingae colonization of the host and a prerequisite for invasive disease. Previous work has established that type IV pili are responsible for K. kingae adherence to host cells. In this work we identify the K. kingae pilus adhesins and localize the adhesive region to the N-terminal domain of these two proteins. We further establish that the two adhesins have distinct binding specificities and also influence other biologic processes. Our study provides new insights into the adherence mechanisms of an increasingly recognized pediatric pathogen and furthers our understanding of K. kingae interactions with host cells, identifying new potential therapeutic targets.
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Affiliation(s)
- Alexandra L. Sacharok
- University of Pennsylvania Perelman School of Medicine, Philadelphia, Pennsylvania, United States of America
| | - Eric A. Porsch
- Department of Pediatrics, Children’s Hospital of Philadelphia, Philadelphia, Pennsylvania, United States of America
| | - Taylor A. Yount
- University of Pennsylvania Perelman School of Medicine, Philadelphia, Pennsylvania, United States of America
| | - Orlaith Keenan
- University of Pennsylvania Perelman School of Medicine, Philadelphia, Pennsylvania, United States of America
| | - Joseph W. St. Geme
- University of Pennsylvania Perelman School of Medicine, Philadelphia, Pennsylvania, United States of America
- Department of Pediatrics, Children’s Hospital of Philadelphia, Philadelphia, Pennsylvania, United States of America
- * E-mail:
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Lamparter T, Babian J, Fröhlich K, Mielke M, Weber N, Wunsch N, Zais F, Schulz K, Aschmann V, Spohrer N, Krauß N. The involvement of type IV pili and the phytochrome CphA in gliding motility, lateral motility and photophobotaxis of the cyanobacterium Phormidium lacuna. PLoS One 2022; 17:e0249509. [PMID: 35085243 PMCID: PMC8794177 DOI: 10.1371/journal.pone.0249509] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [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: 03/17/2021] [Accepted: 12/25/2021] [Indexed: 11/29/2022] Open
Abstract
Phormidium lacuna is a naturally competent, filamentous cyanobacterium that belongs to the order Oscillatoriales. The filaments are motile on agar and other surfaces and display rapid lateral movements in liquid culture. Furthermore, they exhibit a photophobotactic response, a phototactic response towards light that is projected vertically onto the area covered by the culture. However, the molecular mechanisms underlying these phenomena are unclear. We performed the first molecular studies on the motility of an Oscillatoriales member. We generated mutants in which a kanamycin resistance cassette (KanR) was integrated in the phytochrome gene cphA and in various genes of the type IV pilin apparatus. pilM, pilN, pilQ and pilT mutants were defective in gliding motility, lateral movements and photophobotaxis, indicating that type IV pili are involved in all three kinds of motility. pilB mutants were only partially blocked in terms of their responses. pilB is the proposed ATPase for expelling of the filament in type IV pili. The genome reveals proteins sharing weak pilB homology in the ATPase region, these might explain the incomplete phenotype. The cphA mutant revealed a significantly reduced photophobotactic response towards red light. Therefore, our results imply that CphA acts as one of several photophobotaxis photoreceptors or that it could modulate the photophobotaxis response.
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Affiliation(s)
- Tilman Lamparter
- Karlsruhe Institute of Technology KIT, Botanical Institute, Karlsruhe, Germany
- * E-mail:
| | - Jennifer Babian
- Karlsruhe Institute of Technology KIT, Botanical Institute, Karlsruhe, Germany
| | - Katrin Fröhlich
- Karlsruhe Institute of Technology KIT, Botanical Institute, Karlsruhe, Germany
| | - Marion Mielke
- Karlsruhe Institute of Technology KIT, Botanical Institute, Karlsruhe, Germany
| | - Nora Weber
- Karlsruhe Institute of Technology KIT, Botanical Institute, Karlsruhe, Germany
| | - Nadja Wunsch
- Karlsruhe Institute of Technology KIT, Botanical Institute, Karlsruhe, Germany
| | - Finn Zais
- Karlsruhe Institute of Technology KIT, Botanical Institute, Karlsruhe, Germany
| | - Kevin Schulz
- Karlsruhe Institute of Technology KIT, Botanical Institute, Karlsruhe, Germany
| | - Vera Aschmann
- Karlsruhe Institute of Technology KIT, Botanical Institute, Karlsruhe, Germany
| | - Nina Spohrer
- Karlsruhe Institute of Technology KIT, Botanical Institute, Karlsruhe, Germany
| | - Norbert Krauß
- Karlsruhe Institute of Technology KIT, Botanical Institute, Karlsruhe, Germany
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50
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Ozanic M, Marecic V, Knezevic M, Kelava I, Stojková P, Lindgren L, Bröms JE, Sjöstedt A, Abu Kwaik Y, Santic M. The type IV pili component PilO is a virulence determinant of Francisella novicida. PLoS One 2022; 17:e0261938. [PMID: 35077486 PMCID: PMC8789160 DOI: 10.1371/journal.pone.0261938] [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] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2021] [Accepted: 12/14/2021] [Indexed: 12/03/2022] Open
Abstract
Francisella tularensis is a highly pathogenic intracellular bacterium that causes the disease tularemia. While its ability to replicate within cells has been studied in much detail, the bacterium also encodes a less characterised type 4 pili (T4P) system. T4Ps are dynamic adhesive organelles identified as major virulence determinants in many human pathogens. In F. tularensis, the T4P is required for adherence to the host cell, as well as for protein secretion. Several components, including pilins, a pili peptidase, a secretin pore and two ATPases, are required to assemble a functional T4P, and these are encoded within distinct clusters on the Francisella chromosome. While some of these components have been functionally characterised, the role of PilO, if any, still is unknown. Here, we examined the role of PilO in the pathogenesis of F. novicida. Our results show that the PilO is essential for pilus assembly on the bacterial surface. In addition, PilO is important for adherence of F. novicida to human monocyte-derived macrophages, secretion of effector proteins and intracellular replication. Importantly, the pilO mutant is attenuated for virulence in BALB/c mice regardless of the route of infection. Following intratracheal and intradermal infection, the mutant caused no histopathology changes, and demonstrated impaired phagosomal escape and replication within lung liver as well as spleen. Thus, PilO is an essential virulence determinant of F. novicida.
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Affiliation(s)
- Mateja Ozanic
- Faculty of Medicine, Department of Microbiology and Parasitology, University of Rijeka, Rijeka, Croatia
| | - Valentina Marecic
- Faculty of Medicine, Department of Microbiology and Parasitology, University of Rijeka, Rijeka, Croatia
| | - Masa Knezevic
- Faculty of Medicine, Department of Microbiology and Parasitology, University of Rijeka, Rijeka, Croatia
| | - Ina Kelava
- Faculty of Medicine, Department of Microbiology and Parasitology, University of Rijeka, Rijeka, Croatia
| | - Pavla Stojková
- Department of Clinical Microbiology and Laboratory for Molecular Infection Medicine Sweden (MIMS), Umeå University, Umeå, Sweden
| | - Lena Lindgren
- Department of Clinical Microbiology and Laboratory for Molecular Infection Medicine Sweden (MIMS), Umeå University, Umeå, Sweden
| | - Jeanette E. Bröms
- Department of Clinical Microbiology and Laboratory for Molecular Infection Medicine Sweden (MIMS), Umeå University, Umeå, Sweden
| | - Anders Sjöstedt
- Department of Clinical Microbiology and Laboratory for Molecular Infection Medicine Sweden (MIMS), Umeå University, Umeå, Sweden
| | - Yousef Abu Kwaik
- Department of Microbiology and Immunology and Center for Predictive Medicine, College of Medicine, University of Louisville, Louisville, Kentucky, United States of America
| | - Marina Santic
- Faculty of Medicine, Department of Microbiology and Parasitology, University of Rijeka, Rijeka, Croatia
- * E-mail:
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