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Graham LA, Hansen T, Yang Y, Sherik M, Ye Q, Soares BP, Kinrade B, Guo S, Davies PL. Adhesin domains responsible for binding bacteria to surfaces they colonize project outwards from companion split domains. Proteins 2024; 92:933-945. [PMID: 38591850 DOI: 10.1002/prot.26689] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2024] [Revised: 03/07/2024] [Accepted: 03/26/2024] [Indexed: 04/10/2024]
Abstract
Bacterial adhesins attach their hosts to surfaces that the bacteria will colonize. This surface adhesion occurs through specific ligand-binding domains located towards the distal end of the long adhesin molecules. However, recognizing which of the many adhesin domains are structural and which are ligand binding has been difficult up to now. Here we have used the protein structure modeling program AlphaFold2 to predict structures for these giant 0.2- to 1.5-megadalton proteins. Crystal structures previously solved for several adhesin regions are in good agreement with the models. Whereas most adhesin domains are linked in a linear fashion through their N- and C-terminal ends, ligand-binding domains can be recognized by budding out from a companion core domain so that their ligand-binding sites are projected away from the axis of the adhesin for maximal exposure to their targets. These companion domains are "split" in their continuity by projecting the ligand-binding domain outwards. The "split domains" are mostly β-sandwich extender modules, but other domains like a β-solenoid can serve the same function. Bioinformatic analyses of Gram-negative bacterial sequences revealed wide variety ligand-binding domains are used in their Repeats-in-Toxin adhesins. The ligands for many of these domains have yet to be identified but known ligands include various cell-surface glycans, proteins, and even ice. Recognizing the ligands to which the adhesins bind could lead to ways of blocking colonization by bacterial pathogens. Engineering different ligand-binding domains into an adhesin has the potential to change the surfaces to which bacteria bind.
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Affiliation(s)
- Laurie A Graham
- Department of Biomedical and Molecular Sciences, Queen's University, Kingston, Ontario, Canada
| | - Thomas Hansen
- Department of Biomedical and Molecular Sciences, Queen's University, Kingston, Ontario, Canada
| | - Yanzhi Yang
- Department of Biomedical and Molecular Sciences, Queen's University, Kingston, Ontario, Canada
| | - Mustafa Sherik
- Department of Biomedical and Molecular Sciences, Queen's University, Kingston, Ontario, Canada
| | - Qilu Ye
- Department of Biomedical and Molecular Sciences, Queen's University, Kingston, Ontario, Canada
| | - Blake P Soares
- Department of Biomedical and Molecular Sciences, Queen's University, Kingston, Ontario, Canada
| | - Brett Kinrade
- Department of Biomedical and Molecular Sciences, Queen's University, Kingston, Ontario, Canada
| | - Shuaiqi Guo
- Department of Anatomy and Cell Biology, McGill University, Montreal, Quebec, Canada
| | - Peter L Davies
- Department of Biomedical and Molecular Sciences, Queen's University, Kingston, Ontario, Canada
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2
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Sherik M, Eves R, Guo S, Lloyd CJ, Klose KE, Davies PL. Sugar-binding and split domain combinations in repeats-in-toxin adhesins from Vibrio cholerae and Aeromonas veronii mediate cell-surface recognition and hemolytic activities. mBio 2024; 15:e0229123. [PMID: 38171003 PMCID: PMC10865825 DOI: 10.1128/mbio.02291-23] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2023] [Accepted: 12/04/2023] [Indexed: 01/05/2024] Open
Abstract
Many pathogenic Gram-negative bacteria use repeats-in-toxin adhesins for colonization and biofilm formation. In the cholera agent Vibrio cholerae, flagellar-regulated hemagglutinin A (FrhA) enables these functions. Using bioinformatic analysis, a sugar-binding domain was identified in FrhA adjacent to a domain of unknown function. AlphaFold2 indicated the boundaries of both domains to be slightly shorter than previously predicted and assisted in the recognition of the unknown domain as a split immunoglobulin-like fold that can assist in projecting the sugar-binding domain toward its target. The AlphaFold2-predicted structure is in excellent agreement with the molecular envelope obtained from small-angle X-ray scattering analysis of a recombinant construct spanning the sugar-binding and unknown domains. This two-domain construct was probed by glycan micro-array screening and showed binding to mammalian fucosylated glycans, some of which are characteristic erythrocyte markers and intestinal cell epitopes. Isothermal titration calorimetry further showed the construct-bound l-fucose with a Kd of 21 µM. Strikingly, this recombinant protein construct bound and lysed erythrocytes in a concentration-dependent manner, and its hemolytic activity was blocked by the addition of l-fucose. A protein ortholog construct from Aeromonas veronii was also produced and showed a similar glycan-binding pattern, binding affinity, erythrocyte-binding, and hemolytic activities. As demonstrated here with Hep-2 cells, fucose-based inhibitors of this sugar-binding domain can potentially be developed to block colonization by V. cholerae and other pathogenic bacteria that share this adhesin domain.IMPORTANCEThe bacterium, Vibrio cholerae, which causes cholera, uses an adhesion protein to stick to human cells and begin the infection process. One part of this adhesin protein binds to a particular sugar, fucose, on the surface of the target cells. This binding can lead to colonization and killing of the cells by the bacteria. Adding l-fucose to the bacteria before they bind to the human cells can prevent attachment and has promise as a preventative drug to protect against cholera.
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Affiliation(s)
- Mustafa Sherik
- Department of Biomedical and Molecular Sciences, Queen’s University, Kingston, Ontario, Canada
| | - Robert Eves
- Department of Biomedical and Molecular Sciences, Queen’s University, Kingston, Ontario, Canada
| | - Shuaiqi Guo
- Department of Biomedical and Molecular Sciences, Queen’s University, Kingston, Ontario, Canada
| | - Cameron J. Lloyd
- South Texas Center for Emerging Infectious Diseases and Department of Molecular Microbiology and Immunology, University of Texas San Antonio, San Antonio, Texas, USA
| | - Karl E. Klose
- South Texas Center for Emerging Infectious Diseases and Department of Molecular Microbiology and Immunology, University of Texas San Antonio, San Antonio, Texas, USA
| | - Peter L. Davies
- Department of Biomedical and Molecular Sciences, Queen’s University, Kingston, Ontario, Canada
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Zhou Y, Huang J, Wang G, Zhai Z, Ahmed MU, Xia X, Liu C, Jin Y, Pan X, Huang Y, Wu C, Zhang X. Polymyxin B sulfate inhalable microparticles with high-lectin-affinity sugar carriers for efficient treatment of biofilm-associated pulmonary infections. Sci Bull (Beijing) 2023; 68:3225-3239. [PMID: 37973467 DOI: 10.1016/j.scib.2023.11.004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2023] [Revised: 09/29/2023] [Accepted: 10/30/2023] [Indexed: 11/19/2023]
Abstract
Pulmonary infections caused by multidrug-resistant bacteria have become a significant threat to human health. Bacterial biofilms exacerbate the persistence and recurrence of pulmonary infections, hindering the accessibility and effectiveness of antibiotics. In this study, a dry powder inhalation (DPI) consisting of polymyxin B sulfate (PMBS) inhalable microparticles and high-lectin-affinity (HLA) sugar (i.e., raffinose) carriers was developed for treating pulmonary infections and targeting bacterial lectins essential for biofilm growth. The formulated PMBS-HLA DPIs exhibited particle sizes of approximately 3 μm, and surface roughness varied according to the drug-to-carrier ratio. Formulation F5 (PMBS: raffinose = 10:90) demonstrated the highest fine particle fraction (FPF) value (64.86%), signifying its substantially enhanced aerosol performance, potentially attributable to moderate roughness and smallest mass median aerodynamic particle size. The efficacy of PMBS-HLA DPIs in inhibiting biofilm formation and eradicating mature biofilms was significantly improved with the addition of raffinose, suggesting the effectiveness of lectin-binding strategy for combating bacterial biofilm-associated infections. In rat models with acute and chronic pulmonary infections, F5 demonstrated superior bacterial killing and amelioration of inflammatory responses compared to spray-dried PMBS (F0). In conclusion, our HLA carrier-based formulation presents considerable potential for the efficient treatment of multidrug-resistant bacterial biofilm-associated pulmonary infections.
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Affiliation(s)
- Yue Zhou
- State Key Laboratory of Bioactive Molecules and Druggability Assessment, Jinan University, Guangzhou 510006, China; College of Pharmacy, Jinan University, Guangzhou 510006, China
| | - Jiayuan Huang
- School of Medicine, Shenzhen Campus of Sun Yat-sen University, Shenzhen 518107, China
| | - Guanlin Wang
- School of Pharmaceutical Sciences, Sun Yat-sen University, Guangzhou 510006, China
| | - Zizhao Zhai
- State Key Laboratory of Bioactive Molecules and Druggability Assessment, Jinan University, Guangzhou 510006, China; College of Pharmacy, Jinan University, Guangzhou 510006, China
| | - Maizbha Uddin Ahmed
- Department of Industrial and Physical Pharmacy, College of Pharmacy, Purdue University, West Lafayette IN 47907, USA
| | - Xiao Xia
- State Key Laboratory of Bioactive Molecules and Druggability Assessment, Jinan University, Guangzhou 510006, China; College of Pharmacy, Jinan University, Guangzhou 510006, China
| | - Cenfeng Liu
- State Key Laboratory of Bioactive Molecules and Druggability Assessment, Jinan University, Guangzhou 510006, China; College of Pharmacy, Jinan University, Guangzhou 510006, China
| | - Yuzhen Jin
- State Key Laboratory of Bioactive Molecules and Druggability Assessment, Jinan University, Guangzhou 510006, China; College of Pharmacy, Jinan University, Guangzhou 510006, China
| | - Xin Pan
- School of Pharmaceutical Sciences, Sun Yat-sen University, Guangzhou 510006, China
| | - Ying Huang
- State Key Laboratory of Bioactive Molecules and Druggability Assessment, Jinan University, Guangzhou 510006, China; College of Pharmacy, Jinan University, Guangzhou 510006, China.
| | - Chuanbin Wu
- State Key Laboratory of Bioactive Molecules and Druggability Assessment, Jinan University, Guangzhou 510006, China; College of Pharmacy, Jinan University, Guangzhou 510006, China
| | - Xuejuan Zhang
- State Key Laboratory of Bioactive Molecules and Druggability Assessment, Jinan University, Guangzhou 510006, China; College of Pharmacy, Jinan University, Guangzhou 510006, China.
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Lan S, Li Z, Hao H, Liu S, Huang Z, Bai Y, Li Y, Yan X, Gao P, Chen S, Chu Y. A genome-wide transposon mutagenesis screening identifies LppB as a key factor associated with Mycoplasma bovis colonization and invasion into host cells. FASEB J 2023; 37:e23176. [PMID: 37665592 DOI: 10.1096/fj.202300678r] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2023] [Revised: 07/31/2023] [Accepted: 08/22/2023] [Indexed: 09/05/2023]
Abstract
Mycoplasma spp., the smallest self-replicating and genome-reduced organisms, have raised a great concern in both the medical and veterinary fields due to their pathogenicity. The molecular determinants of these wall-less bacterium efficiently use their limited genes to ensure successful infection of the host remain unclear. In the present study, we used the ruminant pathogen Mycoplasma bovis as a model to identify the key factors for colonization and invasion into host cells. We constructed a nonredundant fluorescent transposon mutant library of M. bovis using a modified transposon plasmid, and identified 34 novel adhesion-related genes based on a high-throughput screening approach. Among them, the ΔLppB mutant exhibited the most apparent decrease in adhesion to embryonic bovine lung (EBL) cells. The surface-localized lipoprotein LppB, which is highly conserved in Mycoplasma species, was then confirmed as a key factor for M. bovis adhesion with great immunogenicity. LppB interacted with various components (fibronectin, vitronectin, collagen IV, and laminin) of host extracellular matrix (ECM) and promoted plasminogen activation through tPA to degrade ECM. The 439-502 amino acid region of LppB is a critical domain, and F465 and Y493 are important residues for the plasminogen activation activity. We further revealed LppB as a key factor facilitating internalization through clathrin- and lipid raft-mediated endocytosis, which helps the Mycoplasma invade the host cells. Our study indicates that LppB plays a key role in Mycoplasma infection and is a potential new therapeutic and vaccine target for Mycoplasma species.
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Affiliation(s)
- Shimei Lan
- State Key Laboratory for Animal Disease Control and Prevention, College of Veterinary Medicine, Lanzhou University, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Lanzhou, China
- Gansu Province Research Center for Basic Disciplines of Pathogen Biology, Lanzhou, China
- Key Laboratory of Animal Biosafety Risk Warning and Control (North), Key Laboratory of Ruminant Disease Prevention and Control (West), Ministry of Agricultural and Rural Affairs, Lanzhou, China
| | - Zhangcheng Li
- State Key Laboratory for Animal Disease Control and Prevention, College of Veterinary Medicine, Lanzhou University, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Lanzhou, China
- Gansu Province Research Center for Basic Disciplines of Pathogen Biology, Lanzhou, China
- Key Laboratory of Animal Biosafety Risk Warning and Control (North), Key Laboratory of Ruminant Disease Prevention and Control (West), Ministry of Agricultural and Rural Affairs, Lanzhou, China
| | - Huafang Hao
- State Key Laboratory for Animal Disease Control and Prevention, College of Veterinary Medicine, Lanzhou University, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Lanzhou, China
- Gansu Province Research Center for Basic Disciplines of Pathogen Biology, Lanzhou, China
- Key Laboratory of Animal Biosafety Risk Warning and Control (North), Key Laboratory of Ruminant Disease Prevention and Control (West), Ministry of Agricultural and Rural Affairs, Lanzhou, China
| | - Shuang Liu
- State Key Laboratory for Animal Disease Control and Prevention, College of Veterinary Medicine, Lanzhou University, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Lanzhou, China
- Gansu Province Research Center for Basic Disciplines of Pathogen Biology, Lanzhou, China
- Key Laboratory of Animal Biosafety Risk Warning and Control (North), Key Laboratory of Ruminant Disease Prevention and Control (West), Ministry of Agricultural and Rural Affairs, Lanzhou, China
| | - Zhicheng Huang
- State Key Laboratory for Animal Disease Control and Prevention, College of Veterinary Medicine, Lanzhou University, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Lanzhou, China
- Gansu Province Research Center for Basic Disciplines of Pathogen Biology, Lanzhou, China
- Key Laboratory of Animal Biosafety Risk Warning and Control (North), Key Laboratory of Ruminant Disease Prevention and Control (West), Ministry of Agricultural and Rural Affairs, Lanzhou, China
| | - Yutong Bai
- State Key Laboratory for Animal Disease Control and Prevention, College of Veterinary Medicine, Lanzhou University, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Lanzhou, China
- Gansu Province Research Center for Basic Disciplines of Pathogen Biology, Lanzhou, China
- Key Laboratory of Animal Biosafety Risk Warning and Control (North), Key Laboratory of Ruminant Disease Prevention and Control (West), Ministry of Agricultural and Rural Affairs, Lanzhou, China
| | - Yanzhao Li
- State Key Laboratory for Animal Disease Control and Prevention, College of Veterinary Medicine, Lanzhou University, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Lanzhou, China
- Gansu Province Research Center for Basic Disciplines of Pathogen Biology, Lanzhou, China
- Key Laboratory of Animal Biosafety Risk Warning and Control (North), Key Laboratory of Ruminant Disease Prevention and Control (West), Ministry of Agricultural and Rural Affairs, Lanzhou, China
| | - Xinmin Yan
- State Key Laboratory for Animal Disease Control and Prevention, College of Veterinary Medicine, Lanzhou University, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Lanzhou, China
- Gansu Province Research Center for Basic Disciplines of Pathogen Biology, Lanzhou, China
- Key Laboratory of Animal Biosafety Risk Warning and Control (North), Key Laboratory of Ruminant Disease Prevention and Control (West), Ministry of Agricultural and Rural Affairs, Lanzhou, China
| | - Pengcheng Gao
- State Key Laboratory for Animal Disease Control and Prevention, College of Veterinary Medicine, Lanzhou University, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Lanzhou, China
- Gansu Province Research Center for Basic Disciplines of Pathogen Biology, Lanzhou, China
- Key Laboratory of Animal Biosafety Risk Warning and Control (North), Key Laboratory of Ruminant Disease Prevention and Control (West), Ministry of Agricultural and Rural Affairs, Lanzhou, China
| | - Shengli Chen
- State Key Laboratory for Animal Disease Control and Prevention, College of Veterinary Medicine, Lanzhou University, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Lanzhou, China
- Gansu Province Research Center for Basic Disciplines of Pathogen Biology, Lanzhou, China
- Key Laboratory of Animal Biosafety Risk Warning and Control (North), Key Laboratory of Ruminant Disease Prevention and Control (West), Ministry of Agricultural and Rural Affairs, Lanzhou, China
| | - Yuefeng Chu
- State Key Laboratory for Animal Disease Control and Prevention, College of Veterinary Medicine, Lanzhou University, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Lanzhou, China
- Gansu Province Research Center for Basic Disciplines of Pathogen Biology, Lanzhou, China
- Key Laboratory of Animal Biosafety Risk Warning and Control (North), Key Laboratory of Ruminant Disease Prevention and Control (West), Ministry of Agricultural and Rural Affairs, Lanzhou, China
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5
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Liu X, Lv X, Sun Y, Liu C, Wang R, Liu R, Ma Y, Li Q. Probiotic properties of Lacticaseibacillus rhamnosus grx10 revolved with complete genome. FOOD BIOSCI 2022. [DOI: 10.1016/j.fbio.2022.102219] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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Mycobacterial Adhesion: From Hydrophobic to Receptor-Ligand Interactions. Microorganisms 2022; 10:microorganisms10020454. [PMID: 35208908 PMCID: PMC8875947 DOI: 10.3390/microorganisms10020454] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2021] [Revised: 02/07/2022] [Accepted: 02/12/2022] [Indexed: 11/24/2022] Open
Abstract
Adhesion is crucial for the infective lifestyles of bacterial pathogens. Adhesion to non-living surfaces, other microbial cells, and components of the biofilm extracellular matrix are crucial for biofilm formation and integrity, plus adherence to host factors constitutes a first step leading to an infection. Adhesion is, therefore, at the core of pathogens’ ability to contaminate, transmit, establish residency within a host, and cause an infection. Several mycobacterial species cause diseases in humans and animals with diverse clinical manifestations. Mycobacterium tuberculosis, which enters through the respiratory tract, first adheres to alveolar macrophages and epithelial cells leading up to transmigration across the alveolar epithelium and containment within granulomas. Later, when dissemination occurs, the bacilli need to adhere to extracellular matrix components to infect extrapulmonary sites. Mycobacteria causing zoonotic infections and emerging nontuberculous mycobacterial pathogens follow divergent routes of infection that probably require adapted adhesion mechanisms. New evidence also points to the occurrence of mycobacterial biofilms during infection, emphasizing a need to better understand the adhesive factors required for their formation. Herein, we review the literature on tuberculous and nontuberculous mycobacterial adhesion to living and non-living surfaces, to themselves, to host cells, and to components of the extracellular matrix.
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Luo A, Wang F, Sun D, Liu X, Xin B. Formation, Development, and Cross-Species Interactions in Biofilms. Front Microbiol 2022; 12:757327. [PMID: 35058893 PMCID: PMC8764401 DOI: 10.3389/fmicb.2021.757327] [Citation(s) in RCA: 17] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2021] [Accepted: 11/29/2021] [Indexed: 12/25/2022] Open
Abstract
Biofilms, which are essential vectors of bacterial survival, protect microbes from antibiotics and host immune attack and are one of the leading causes that maintain drug-resistant chronic infections. In nature, compared with monomicrobial biofilms, polymicrobial biofilms composed of multispecies bacteria predominate, which means that it is significant to explore the interactions between microorganisms from different kingdoms, species, and strains. Cross-microbial interactions exist during biofilm development, either synergistically or antagonistically. Although research into cross-species biofilms remains at an early stage, in this review, the important mechanisms that are involved in biofilm formation are delineated. Then, recent studies that investigated cross-species cooperation or synergy, competition or antagonism in biofilms, and various components that mediate those interactions will be elaborated. To determine approaches that minimize the harmful effects of biofilms, it is important to understand the interactions between microbial species. The knowledge gained from these investigations has the potential to guide studies into microbial sociality in natural settings and to help in the design of new medicines and therapies to treat bacterial infections.
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Affiliation(s)
- Aihua Luo
- Department of Stomatology, Guizhou Provincial People's Hospital, Guiyang, China
| | - Fang Wang
- Department of Pharmacy, Qingdao Stomatological Hospital Affiliated to Qingdao University, Qingdao, China
| | - Degang Sun
- Department of Cariology and Endodontology, Qingdao Stomatological Hospital Affiliated to Qingdao University, Qingdao, China
| | - Xueyu Liu
- Department of Cariology and Endodontology, Qingdao Stomatological Hospital Affiliated to Qingdao University, Qingdao, China.,Central Laboratory, Qingdao Stomatological Hospital Affiliated to Qingdao University, Qingdao, China
| | - Bingchang Xin
- Department of Cariology and Endodontology, Qingdao Stomatological Hospital Affiliated to Qingdao University, Qingdao, China.,Central Laboratory, Qingdao Stomatological Hospital Affiliated to Qingdao University, Qingdao, China
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Guo S, Zahiri H, Stevens C, Spaanderman DC, Milroy LG, Ottmann C, Brunsveld L, Voets IK, Davies PL. Molecular basis for inhibition of adhesin-mediated bacterial-host interactions through a peptide-binding domain. Cell Rep 2021; 37:110002. [PMID: 34788627 DOI: 10.1016/j.celrep.2021.110002] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2021] [Revised: 08/26/2021] [Accepted: 10/25/2021] [Indexed: 12/17/2022] Open
Abstract
Infections typically begin with pathogens adhering to host cells. For bacteria, this adhesion can occur through specific ligand-binding domains. We identify a 20-kDa peptide-binding domain (PBD) in a 1.5-MDa RTX adhesin of a Gram-negative marine bacterium that colonizes diatoms. The crystal structure of this Ca2+-dependent PBD suggests that it may bind the C termini of host cell-surface proteins. A systematic peptide library analysis reveals an optimal tripeptide sequence with 30-nM affinity for the PBD, and X-ray crystallography details its peptide-protein interactions. Binding of the PBD to the diatom partner of the bacteria can be inhibited or competed away by the peptide, providing a molecular basis for inhibiting bacterium-host interactions. We further show that this PBD is found in other bacteria, including human pathogens such as Vibrio cholerae and Aeromonas veronii. Here, we produce the PBD ortholog from A. veronii and demonstrate, using the same peptide inhibitor, how pathogens may be prevented from adhering to their hosts.
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Affiliation(s)
- Shuaiqi Guo
- Department of Biomedical and Molecular Sciences, Queen's University, Kingston, ON K7L 3N6, Canada; Laboratory of Self-Organizing Soft Matter, Eindhoven University of Technology PO Box 513, 5600 MB Eindhoven, the Netherlands; Laboratory of Chemical Biology, Eindhoven University of Technology PO Box 513, 5600 MB Eindhoven, the Netherlands; Institute for Complex Molecular Systems, Eindhoven University of Technology PO Box 513, 5600 MB Eindhoven, the Netherlands
| | - Hossein Zahiri
- Department of Biomedical and Molecular Sciences, Queen's University, Kingston, ON K7L 3N6, Canada
| | - Corey Stevens
- Department of Biomedical and Molecular Sciences, Queen's University, Kingston, ON K7L 3N6, Canada
| | - Daniel C Spaanderman
- Laboratory of Chemical Biology, Eindhoven University of Technology PO Box 513, 5600 MB Eindhoven, the Netherlands; Laboratory of Macromolecular and Organic Chemistry, Eindhoven University of Technology PO Box 513, 5600 MB Eindhoven, the Netherlands; Institute for Complex Molecular Systems, Eindhoven University of Technology PO Box 513, 5600 MB Eindhoven, the Netherlands
| | - Lech-Gustav Milroy
- Laboratory of Chemical Biology, Eindhoven University of Technology PO Box 513, 5600 MB Eindhoven, the Netherlands; Institute for Complex Molecular Systems, Eindhoven University of Technology PO Box 513, 5600 MB Eindhoven, the Netherlands
| | - Christian Ottmann
- Laboratory of Chemical Biology, Eindhoven University of Technology PO Box 513, 5600 MB Eindhoven, the Netherlands; Institute for Complex Molecular Systems, Eindhoven University of Technology PO Box 513, 5600 MB Eindhoven, the Netherlands
| | - Luc Brunsveld
- Laboratory of Chemical Biology, Eindhoven University of Technology PO Box 513, 5600 MB Eindhoven, the Netherlands; Institute for Complex Molecular Systems, Eindhoven University of Technology PO Box 513, 5600 MB Eindhoven, the Netherlands
| | - Ilja K Voets
- Laboratory of Self-Organizing Soft Matter, Eindhoven University of Technology PO Box 513, 5600 MB Eindhoven, the Netherlands; Laboratory of Macromolecular and Organic Chemistry, Eindhoven University of Technology PO Box 513, 5600 MB Eindhoven, the Netherlands; Institute for Complex Molecular Systems, Eindhoven University of Technology PO Box 513, 5600 MB Eindhoven, the Netherlands
| | - Peter L Davies
- Department of Biomedical and Molecular Sciences, Queen's University, Kingston, ON K7L 3N6, Canada.
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