1
|
Camargo A, Ramírez JD, Kiu R, Hall LJ, Muñoz M. Unveiling the pathogenic mechanisms of Clostridium perfringens toxins and virulence factors. Emerg Microbes Infect 2024; 13:2341968. [PMID: 38590276 PMCID: PMC11057404 DOI: 10.1080/22221751.2024.2341968] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2023] [Accepted: 04/06/2024] [Indexed: 04/10/2024]
Abstract
Clostridium perfringens causes multiple diseases in humans and animals. Its pathogenic effect is supported by a broad and heterogeneous arsenal of toxins and other virulence factors associated with a specific host tropism. Molecular approaches have indicated that most C. perfringens toxins produce membrane pores, leading to osmotic cell disruption and apoptosis. However, identifying mechanisms involved in cell tropism and selective toxicity effects should be studied more. The differential presence and polymorphisms of toxin-encoding genes and genes encoding other virulence factors suggest that molecular mechanisms might exist associated with host preference, receptor binding, and impact on the host; however, this information has not been reviewed in detail. Therefore, this review aims to clarify the current state of knowledge on the structural features and mechanisms of action of the major toxins and virulence factors of C. perfringens and discuss the impact of genetic diversity of toxinotypes in tropism for several hosts.
Collapse
Affiliation(s)
- Anny Camargo
- Centro de Investigaciones en Microbiología y Biotecnología-UR (CIMBIUR), Facultad de Ciencias Naturales, Universidad del Rosario, Bogotá, Colombia
- Health Sciences Faculty, Universidad de Boyacá, Tunja, Colombia
| | - Juan David Ramírez
- Centro de Investigaciones en Microbiología y Biotecnología-UR (CIMBIUR), Facultad de Ciencias Naturales, Universidad del Rosario, Bogotá, Colombia
- Molecular Microbiology Laboratory, Department of Pathology, Molecular and Cell-Based Medicine, Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - Raymond Kiu
- Institute of Microbiology and Infection, College of Medical and Dental Sciences, University of Birmingham, Birmingham, UK
- Gut Microbes and Health, Quadram Institute Bioscience, Norwich Research Park, Norwich, UK
| | - Lindsay J. Hall
- Institute of Microbiology and Infection, College of Medical and Dental Sciences, University of Birmingham, Birmingham, UK
- Gut Microbes and Health, Quadram Institute Bioscience, Norwich Research Park, Norwich, UK
- Norwich Medical School, University of East Anglia, Norwich, UK
| | - Marina Muñoz
- Centro de Investigaciones en Microbiología y Biotecnología-UR (CIMBIUR), Facultad de Ciencias Naturales, Universidad del Rosario, Bogotá, Colombia
- Instituto de Biotecnología-UN (IBUN), Universidad Nacional de Colombia, Bogotá, Colombia
| |
Collapse
|
2
|
Li H, Wang R, Xu P, Yuan C, Huang M, Jiang L. Elucidating the molecular basis of PECAM-1 and Tie2 interaction from binding dynamics and complex formation. Biochem Biophys Res Commun 2024; 735:150484. [PMID: 39094232 DOI: 10.1016/j.bbrc.2024.150484] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2024] [Revised: 07/24/2024] [Accepted: 07/30/2024] [Indexed: 08/04/2024]
Abstract
BACKGROUND Endothelial hyperpermeability-induced vascular dysfunction is a prevalent and significant characteristic in critical illnesses such as sepsis and other conditions marked by acute systemic inflammation. Platelet endothelial cell adhesion molecule-1 (PECAM-1) and Tie2 serve as transmembrane receptors within endothelial cells (ECs), playing pivotal roles not only in maintaining EC-EC junctions but also in influencing vasculogenesis, vessel homeostasis, and vascular remodeling. OBJECTIVES At present, the molecular basis of the PECAM-1-Tie2 interaction remains inadequately elucidated. In the study, recombinant soluble PECAM-1 (sPECAM-1) and Tie2 (sTie2) were expressed by Drosophila S2 and HEK293 expression systems, respectively. The interactions between sPECAM-1 and sTie2 were investigated using the Surface Plasmon Resonance (SPR) and size-exclusion chromatography methods. An immunofluorescence assay was used to detect the binding of sPECAM-1 and sTie2 on endothelial cells. RESULTS PECAM-1 was found to bind with sTie2 in a sodium and pH-dependent manner as confirmed by the ELISA, the D5-D6 domains of PECAM-1 might play a crucial role in binding with sTie2. Surface Plasmon Resonance (SPR) results showed that the full length of sPECAM-1 has the strongest binding affinity (KD = 48.4 nM) with sTie2, compared to sPECAM-1-D1-D4 and sPECAM-1-D1-D2. This result is consistent with that in the ELISA. In addition, size-exclusion chromatography demonstrated that sPECAM-1, sTie2, and Ang1 can form a ternary complex. CONCLUSION In this study, we determined that sPECAM-1 binds to sTie2 in a pH and sodium-dependent manner. The full length of sPECAM-1 has the strongest binding affinity, and the D5-D6 domains in sPECAM-1 play a crucial role in the interaction between sPECAM-1 and sTie2.
Collapse
Affiliation(s)
- Hao Li
- College of Chemistry, Fuzhou University, Fuzhou, 350116, China
| | - Rui Wang
- College of Chemistry, Fuzhou University, Fuzhou, 350116, China
| | - Peng Xu
- College of Biological Science and Engineering, Fuzhou University, Fuzhou, Fujian, 350116, China
| | - Cai Yuan
- College of Biological Science and Engineering, Fuzhou University, Fuzhou, Fujian, 350116, China
| | - Mingdong Huang
- College of Chemistry, Fuzhou University, Fuzhou, 350116, China; The National & Local Joint Engineering Research Center on Biopharmaceutical and Photodynamic Therapy Technologies, Fuzhou University, Fuzhou, Fujian, 350116, China.
| | - Longguang Jiang
- College of Chemistry, Fuzhou University, Fuzhou, 350116, China; The National & Local Joint Engineering Research Center on Biopharmaceutical and Photodynamic Therapy Technologies, Fuzhou University, Fuzhou, Fujian, 350116, China.
| |
Collapse
|
3
|
Hussain H, Fadel A, Garcia E, Hernandez RJ, Saadoon ZF, Naseer L, Casmartino E, Hamad M, Schnepp T, Sarfraz R, Angly S, Jayakumar AR. Clostridial Myonecrosis: A Comprehensive Review of Toxin Pathophysiology and Management Strategies. Microorganisms 2024; 12:1464. [PMID: 39065232 PMCID: PMC11278868 DOI: 10.3390/microorganisms12071464] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2024] [Revised: 07/13/2024] [Accepted: 07/17/2024] [Indexed: 07/28/2024] Open
Abstract
Clostridial myonecrosis, commonly known as gas gangrene (GG), is a rapidly progressing and potentially fatal bacterial infection that primarily affects muscle and soft tissue. In the United States, the incidence of GG is roughly 1000 cases per year, while, in developing countries, the incidence is higher. This condition is most often caused by Clostridium perfringens, a Gram-positive, spore-forming anaerobic bacterium widely distributed in the environment, although other Clostridium species have also been reported to cause GG. The CP genome contains over 200 transport-related genes, including ABC transporters, which facilitate the uptake of sugars, amino acids, nucleotides, and ions from the host environment. There are two main subtypes of GG: traumatic GG, resulting from injuries that introduce Clostridium spores into deep tissue, where anaerobic conditions allow for bacterial growth and toxin production, and spontaneous GG, which is rarer and often occurs in immunocompromised patients. Clostridium species produce various toxins (e.g., alpha, theta, beta) that induce specific downstream signaling changes in cellular pathways, causing apoptosis or severe, fatal immunological conditions. For example, the Clostridium perfringens alpha toxin (CPA) targets the host cell's plasma membrane, hydrolyzing sphingomyelin and phosphatidylcholine, which triggers necrosis and apoptosis. The clinical manifestations of clostridial myonecrosis vary. Some patients experience the sudden onset of severe pain, swelling, and muscle tenderness, with the infection progressing rapidly to widespread tissue necrosis, systemic toxicity, and, if untreated, death. Other patients present with discharge, pain, and features of cellulitis. The diagnosis of GG primarily involves clinical evaluation, imaging studies such as X-rays, computer tomography (CT) scans, and culture. The treatment of GG involves surgical exploration, broad-spectrum antibiotics, antitoxin, and hyperbaric oxygen therapy, which is considered an adjunctive treatment to inhibit anaerobic bacterial growth and enhance the antibiotic efficacy. Early recognition and prompt, comprehensive treatment are critical to improving the outcomes for patients affected by this severe and life-threatening condition.
Collapse
Affiliation(s)
- Hussain Hussain
- Department of Internal Medicine, Kendall Hospital-HCA Florida Healthcare, Miami, FL 33136, USA;
- Department of Internal Medicine and Infectious Disease, Larkin Community Hospital, Miami, FL 33143, USA; (E.G.); (Z.F.S.); (L.N.); (E.C.); (M.H.); (T.S.); (R.S.); (S.A.)
| | - Aya Fadel
- Department of Internal Medicine, Ocean University Medical Center—Hackensack Meridian Health, Brick, NJ 08724, USA;
| | - Efrain Garcia
- Department of Internal Medicine and Infectious Disease, Larkin Community Hospital, Miami, FL 33143, USA; (E.G.); (Z.F.S.); (L.N.); (E.C.); (M.H.); (T.S.); (R.S.); (S.A.)
| | - Robert J. Hernandez
- Department of Internal Medicine, Kendall Hospital-HCA Florida Healthcare, Miami, FL 33136, USA;
- Department of Internal Medicine and Infectious Disease, Larkin Community Hospital, Miami, FL 33143, USA; (E.G.); (Z.F.S.); (L.N.); (E.C.); (M.H.); (T.S.); (R.S.); (S.A.)
| | - Zahraa F. Saadoon
- Department of Internal Medicine and Infectious Disease, Larkin Community Hospital, Miami, FL 33143, USA; (E.G.); (Z.F.S.); (L.N.); (E.C.); (M.H.); (T.S.); (R.S.); (S.A.)
| | - Lamia Naseer
- Department of Internal Medicine and Infectious Disease, Larkin Community Hospital, Miami, FL 33143, USA; (E.G.); (Z.F.S.); (L.N.); (E.C.); (M.H.); (T.S.); (R.S.); (S.A.)
| | - Ekaterina Casmartino
- Department of Internal Medicine and Infectious Disease, Larkin Community Hospital, Miami, FL 33143, USA; (E.G.); (Z.F.S.); (L.N.); (E.C.); (M.H.); (T.S.); (R.S.); (S.A.)
| | - Mohammad Hamad
- Department of Internal Medicine and Infectious Disease, Larkin Community Hospital, Miami, FL 33143, USA; (E.G.); (Z.F.S.); (L.N.); (E.C.); (M.H.); (T.S.); (R.S.); (S.A.)
| | - Taylor Schnepp
- Department of Internal Medicine and Infectious Disease, Larkin Community Hospital, Miami, FL 33143, USA; (E.G.); (Z.F.S.); (L.N.); (E.C.); (M.H.); (T.S.); (R.S.); (S.A.)
| | - Rehan Sarfraz
- Department of Internal Medicine and Infectious Disease, Larkin Community Hospital, Miami, FL 33143, USA; (E.G.); (Z.F.S.); (L.N.); (E.C.); (M.H.); (T.S.); (R.S.); (S.A.)
| | - Sohair Angly
- Department of Internal Medicine and Infectious Disease, Larkin Community Hospital, Miami, FL 33143, USA; (E.G.); (Z.F.S.); (L.N.); (E.C.); (M.H.); (T.S.); (R.S.); (S.A.)
| | - Arumugam R. Jayakumar
- Department of Obstetrics, Gynecology and Reproductive Sciences, University of Miami Miller School of Medicine, Miami, FL 33136, USA
| |
Collapse
|
4
|
Gigon L, Müller P, Haenni B, Iacovache I, Barbo M, Gosheva G, Yousefi S, Soragni A, von Ballmoos C, Zuber B, Simon HU. Membrane damage by MBP-1 is mediated by pore formation and amplified by mtDNA. Cell Rep 2024; 43:114084. [PMID: 38583154 DOI: 10.1016/j.celrep.2024.114084] [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: 10/06/2023] [Revised: 12/28/2023] [Accepted: 03/25/2024] [Indexed: 04/09/2024] Open
Abstract
Eosinophils play a crucial role in host defense while also contributing to immunopathology through the release of inflammatory mediators. Characterized by distinctive cytoplasmic granules, eosinophils securely store and rapidly release various proteins exhibiting high toxicity upon extracellular release. Among these, major basic protein 1 (MBP-1) emerges as an important mediator in eosinophil function against pathogens and in eosinophil-associated diseases. While MBP-1 targets both microorganisms and host cells, its precise mechanism remains elusive. We demonstrate that formation of small pores by MBP-1 in lipid bilayers induces membrane permeabilization and disrupts potassium balance. Additionally, we reveal that mitochondrial DNA (mtDNA) present in eosinophil extracellular traps (EETs) amplifies MBP-1 toxic effects, underscoring the pivotal role of mtDNA in EETs. Furthermore, we present evidence indicating that absence of CpG methylation in mtDNA contributes to the regulation of MBP-1-mediated toxicity. Taken together, our data suggest that the mtDNA scaffold within extracellular traps promotes MBP-1 toxicity.
Collapse
Affiliation(s)
- Lea Gigon
- Institute of Pharmacology, University of Bern, 3010 Bern, Switzerland
| | - Philipp Müller
- Department of Chemistry, Biochemistry, and Pharmaceutical Sciences, University of Bern, 3012 Bern, Switzerland
| | - Beat Haenni
- Institute of Anatomy, University of Bern, 3012 Bern, Switzerland
| | - Ioan Iacovache
- Institute of Anatomy, University of Bern, 3012 Bern, Switzerland
| | - Maruša Barbo
- Institute of Pharmacology, University of Bern, 3010 Bern, Switzerland; Faculty of Pharmacy, University of Ljubljana, 1000 Ljubljana, Slovenia
| | - Gordana Gosheva
- Institute of Pharmacology, University of Bern, 3010 Bern, Switzerland; Faculty of Pharmacy, University of Ljubljana, 1000 Ljubljana, Slovenia
| | - Shida Yousefi
- Institute of Pharmacology, University of Bern, 3010 Bern, Switzerland
| | - Alice Soragni
- Department of Orthopedic Surgery, David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, CA 90095, USA
| | - Christoph von Ballmoos
- Department of Chemistry, Biochemistry, and Pharmaceutical Sciences, University of Bern, 3012 Bern, Switzerland
| | - Benoît Zuber
- Institute of Anatomy, University of Bern, 3012 Bern, Switzerland
| | - Hans-Uwe Simon
- Institute of Pharmacology, University of Bern, 3010 Bern, Switzerland; Institute of Biochemistry, Brandenburg Medical School, 16816 Neuruppin, Germany.
| |
Collapse
|
5
|
Hoonakker M, Zariri A, de Brouwer L, David D, Borgman A, Sloots A. An in vitro assay for toxicity testing of Clostridium perfringens type C β-toxin. Front Immunol 2024; 15:1373411. [PMID: 38646535 PMCID: PMC11026656 DOI: 10.3389/fimmu.2024.1373411] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2024] [Accepted: 03/19/2024] [Indexed: 04/23/2024] Open
Abstract
Introduction Veterinary vaccines against Clostridium perfringens type C need to be tested for absence of toxicity, as mandated by pharmacopoeias worldwide. This toxicity testing is required at multiple manufacturing steps and relies on outdated mouse tests that involve severe animal suffering. Clostridium perfringens type C produces several toxins of which the β-toxin is the primary component responsible for causing disease. Here, we describe the successful development of a new cell-based in vitro assay that can address the specific toxicity of the β-toxin. Methods Development of the cell-based assay followed the principle of in vitro testing developed for Cl. septicum vaccines, which is based on Vero cells. We screened four cell lines and selected the THP-1 cell line, which was shown to be the most specific and sensitive for β-toxin activity, in combination with a commercially available method to determine cell viability (MTS assay) as a readout. Results The current animal test is estimated to detect 100 - 1000-fold dilutions of the Cl. perfringens type C non-inactivated antigen. When tested with an active Cl. perfringens type C antigen preparation, derived from a commercial vaccine manufacturing process, our THP-1 cell-based assay was able to detect toxin activity from undiluted to over 10000-fold dilution, showing a linear range between approximately 1000- and 10000-fold dilutions. Assay specificity for the β-toxin was confirmed with neutralizing antibodies and lack of reaction to Cl. perfringens culture medium. In addition, assay parameters demonstrated good repeatability. Conclusions Here, we have shown proof of concept for a THP-1 cell-based assay for toxicity testing of veterinary Cl. perfringens type C vaccines that is suitable for all vaccine production steps. This result represents a significant step towards the replacement of animal-based toxicity testing of this veterinary clostridial antigen. As a next step, assessment of the assay's sensitivity and repeatability and validation of the method will have to be performed in a commercial manufacturing context in order to formally implement the assay in vaccine quality control.
Collapse
Affiliation(s)
| | | | | | | | | | - Arjen Sloots
- Department of Product Characterization and Formulation, Intravacc B.V., Bilthoven, Netherlands
| |
Collapse
|
6
|
Wu M, Xu X, Hu R, Chen Q, Chen L, Yuan Y, Li J, Zhou L, Feng S, Wang L, Chen S, Gu M. A Membrane-Targeted Photosensitizer Prevents Drug Resistance and Induces Immune Response in Treating Candidiasis. ADVANCED SCIENCE (WEINHEIM, BADEN-WURTTEMBERG, GERMANY) 2023; 10:e2207736. [PMID: 37875397 PMCID: PMC10724446 DOI: 10.1002/advs.202207736] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/29/2022] [Revised: 09/20/2023] [Indexed: 10/26/2023]
Abstract
Candida albicans (C. albicans), a ubiquitous polymorphic fungus in humans, causes different types of candidiasis, including oral candidiasis (OC) and vulvovaginal candidiasis (VVC), which are physically and mentally concerning and financially costly. Thus, developing alternative antifungals that prevent drug resistance and induce immunity to eliminate Candida biofilms is crucial. Herein, a novel membrane-targeted aggregation-induced emission (AIE) photosensitizer (PS), TBTCP-QY, is developed for highly efficient photodynamic therapy (PDT) of candidiasis. TBTCP-QY has a high molar absorption coefficient and an excellent ability to generate 1 O2 and •OH, entering the interior of biofilms due to its high permeability. Furthermore, TBTCP-QY can efficiently inhibit biofilm formation by suppressing the expression of genes related to the adhesion (ALS3, EAP1, and HWP1), invasion (SAP1 and SAP2), and drug resistance (MDR1) of C. albicans, which is also advantageous for eliminating potential fungal resistance to treat clinical infectious diseases. TBTCP-QY-mediated PDT efficiently targets OC and VVC in vivo in a mouse model, induces immune response, relieves inflammation, and accelerates the healing of mucosal defects to combat infections caused by clinically isolated fluconazole-resistant strains. Moreover, TBTCP-QY demonstrates excellent biocompatibility, suggesting its potential applications in the clinical treatment of OC and VVC.
Collapse
Affiliation(s)
- Ming‐Yu Wu
- Department of GastroenterologyMinistry of Education Key Laboratory of Combinatorial Biosynthesis and Drug DiscoveryTaiKang Center for Life and Medical SciencesZhongnan Hospital of Wuhan UniversitySchool of Pharmaceutical SciencesWuhan UniversityWuhan430071China
- Sichuan Engineering Research Center for Biomimetic Synthesis of Natural DrugsSchool of Life Science and EngineeringSouthwest Jiaotong UniversityChengduSichuan610031China
| | - Xiaoyu Xu
- Department of GastroenterologyMinistry of Education Key Laboratory of Combinatorial Biosynthesis and Drug DiscoveryTaiKang Center for Life and Medical SciencesZhongnan Hospital of Wuhan UniversitySchool of Pharmaceutical SciencesWuhan UniversityWuhan430071China
| | - Rui Hu
- Department of GastroenterologyMinistry of Education Key Laboratory of Combinatorial Biosynthesis and Drug DiscoveryTaiKang Center for Life and Medical SciencesZhongnan Hospital of Wuhan UniversitySchool of Pharmaceutical SciencesWuhan UniversityWuhan430071China
- Department of Respiratory DiseasesThe Research and Application Center of Precision MedicineThe Second Affiliated Hospital of Zhengzhou UniversityZhengzhou UniversityZhengzhou450014China
| | - Qingrong Chen
- Department of GastroenterologyMinistry of Education Key Laboratory of Combinatorial Biosynthesis and Drug DiscoveryTaiKang Center for Life and Medical SciencesZhongnan Hospital of Wuhan UniversitySchool of Pharmaceutical SciencesWuhan UniversityWuhan430071China
| | - Luojia Chen
- Department of GastroenterologyMinistry of Education Key Laboratory of Combinatorial Biosynthesis and Drug DiscoveryTaiKang Center for Life and Medical SciencesZhongnan Hospital of Wuhan UniversitySchool of Pharmaceutical SciencesWuhan UniversityWuhan430071China
| | - Yuncong Yuan
- Department of GastroenterologyMinistry of Education Key Laboratory of Combinatorial Biosynthesis and Drug DiscoveryTaiKang Center for Life and Medical SciencesZhongnan Hospital of Wuhan UniversitySchool of Pharmaceutical SciencesWuhan UniversityWuhan430071China
| | - Jie Li
- Department of Medical Intensive Care UnitMaternal and Child Health Hospital of Hubei ProvinceTongji Medical CollegeHuazhong University of Science and TechnologyWuhanHubei430070China
| | - Li Zhou
- Department of GastroenterologyMinistry of Education Key Laboratory of Combinatorial Biosynthesis and Drug DiscoveryTaiKang Center for Life and Medical SciencesZhongnan Hospital of Wuhan UniversitySchool of Pharmaceutical SciencesWuhan UniversityWuhan430071China
| | - Shun Feng
- Sichuan Engineering Research Center for Biomimetic Synthesis of Natural DrugsSchool of Life Science and EngineeringSouthwest Jiaotong UniversityChengduSichuan610031China
| | - Lianrong Wang
- Department of GastroenterologyMinistry of Education Key Laboratory of Combinatorial Biosynthesis and Drug DiscoveryTaiKang Center for Life and Medical SciencesZhongnan Hospital of Wuhan UniversitySchool of Pharmaceutical SciencesWuhan UniversityWuhan430071China
- Department of Respiratory DiseasesThe Research and Application Center of Precision MedicineThe Second Affiliated Hospital of Zhengzhou UniversityZhengzhou UniversityZhengzhou450014China
| | - Shi Chen
- Department of GastroenterologyMinistry of Education Key Laboratory of Combinatorial Biosynthesis and Drug DiscoveryTaiKang Center for Life and Medical SciencesZhongnan Hospital of Wuhan UniversitySchool of Pharmaceutical SciencesWuhan UniversityWuhan430071China
| | - Meijia Gu
- Department of GastroenterologyMinistry of Education Key Laboratory of Combinatorial Biosynthesis and Drug DiscoveryTaiKang Center for Life and Medical SciencesZhongnan Hospital of Wuhan UniversitySchool of Pharmaceutical SciencesWuhan UniversityWuhan430071China
- Department of Respiratory DiseasesThe Research and Application Center of Precision MedicineThe Second Affiliated Hospital of Zhengzhou UniversityZhengzhou UniversityZhengzhou450014China
| |
Collapse
|
7
|
Vilhena C, Du S, Battista M, Westermann M, Kohler T, Hammerschmidt S, Zipfel PF. The choline-binding proteins PspA, PspC, and LytA of Streptococcus pneumoniae and their interaction with human endothelial and red blood cells. Infect Immun 2023; 91:e0015423. [PMID: 37551971 PMCID: PMC10501214 DOI: 10.1128/iai.00154-23] [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: 04/26/2023] [Accepted: 06/23/2023] [Indexed: 08/09/2023] Open
Abstract
Streptococcus pneumoniae is a Gram-positive opportunistic pathogen that can colonize the upper respiratory tract. It is a leading cause of a wide range of infectious diseases, including community-acquired pneumonia and meningitis. Pneumococcal infections cause 1-2 million deaths per year, most of which occur in developing countries. Here, we focused on three choline-binding proteins (CBPs), i.e., PspC, PspA, and LytA. These pneumococcal proteins have different surface-exposed regions but share related choline-binding anchors. These surface-exposed pneumococcal proteins are in direct contact with host cells and have diverse functions. We explored the role of the three CBPs on adhesion and pathogenicity in a human host by performing relevant imaging and functional analyses, such as electron microscopy, confocal laser scanning microscopy, and functional quantitative assays, targeting biofilm formation and the hemolytic capacity of S. pneumoniae. In vitro biofilm formation assays and electron microscopy experiments were used to examine the ability of knockout mutant strains lacking the lytA, pspC, or pspA genes to adhere to surfaces. We found that LytA plays an important role in robust synthesis of the biofilm matrix. PspA and PspC appeared crucial for the hemolytic effects of S. pneumoniae on human red blood cells. Furthermore, all knockout mutants caused less damage to endothelial cells than wild-type bacteria, highlighting the significance of each CPB for the overall pathogenicity of S. pneumoniae. Hence, in addition to their structural function within the cell wall of S. pneumoniae, each of these three surface-exposed CBPs controls or mediates multiple steps during bacterial pathogenesis.
Collapse
Affiliation(s)
- Cláudia Vilhena
- Department of Infection Biology, Leibniz Institute for Natural Product Research and Infection Biology, Jena, Germany
| | - Shanshan Du
- Department of Infection Biology, Leibniz Institute for Natural Product Research and Infection Biology, Jena, Germany
| | - Miriana Battista
- Department of Infection Biology, Leibniz Institute for Natural Product Research and Infection Biology, Jena, Germany
| | - Martin Westermann
- Centre for Electron Microscopy, Jena University Hospital, Friedrich-Schiller-University of Jena, Jena, Germany
| | - Thomas Kohler
- Department of Molecular Genetics and Infection Biology, Center for Functional Genomics of Microbes, Interfaculty Institute for Genetics and Functional Genomics, University of Greifswald, Greifswald, Germany
| | - Sven Hammerschmidt
- Department of Molecular Genetics and Infection Biology, Center for Functional Genomics of Microbes, Interfaculty Institute for Genetics and Functional Genomics, University of Greifswald, Greifswald, Germany
| | - Peter F. Zipfel
- Department of Infection Biology, Leibniz Institute for Natural Product Research and Infection Biology, Jena, Germany
- Institute of Microbiology, Friedrich-Schiller-University, Jena, Germany
| |
Collapse
|
8
|
Battista M, Hoffmann B, Bachelot Y, Zimmermann L, Teuber L, Jost A, Linde S, Westermann M, Müller MM, Slevogt H, Hammerschmidt S, Figge MT, Vilhena C, Zipfel PF. The role of pneumococcal extracellular vesicles on the pathophysiology of the kidney disease hemolytic uremic syndrome. mSphere 2023; 8:e0014223. [PMID: 37358300 PMCID: PMC10449520 DOI: 10.1128/msphere.00142-23] [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: 04/11/2023] [Accepted: 04/20/2023] [Indexed: 06/27/2023] Open
Abstract
Streptococcus pneumoniae-induced hemolytic uremic syndrome (Sp-HUS) is a kidney disease characterized by microangiopathic hemolytic anemia, thrombocytopenia, and acute kidney injury. This disease is frequently underdiagnosed and its pathophysiology is poorly understood. In this work, we compared clinical strains, isolated from infant Sp-HUS patients, with a reference pathogenic strain D39, for host cytotoxicity and further explored the role of Sp-derived extracellular vesicles (EVs) in the pathogenesis of an HUS infection. In comparison with the wild-type strain, pneumococcal HUS strains caused significant lysis of human erythrocytes and increased the release of hydrogen peroxide. Isolated Sp-HUS EVs were characterized by performing dynamic light-scattering microscopy and proteomic analysis. Sp-HUS strain released EVs at a constant concentration during growth, yet the size of the EVs varied and several subpopulations emerged at later time points. The cargo of the Sp-HUS EVs included several virulence factors at high abundance, i.e., the ribosomal subunit assembly factor BipA, the pneumococcal surface protein A, the lytic enzyme LytC, several sugar utilization, and fatty acid synthesis proteins. Sp-HUS EVs strongly downregulated the expression of the endothelial surface marker platelet endothelial cell adhesion molecule-1 and were internalized by human endothelial cells. Sp-HUS EVs elicited the release of pro-inflammatory cytokines (interleukin [IL]-1β, IL-6) and chemokines (CCL2, CCL3, CXCL1) by human monocytes. These findings shed new light on the overall function of Sp-EVs, in the scope of infection-mediated HUS, and suggest new avenues of research for exploring the usefulness of Sp-EVs as therapeutic and diagnostic targets. IMPORTANCE Streptococcus pneumoniae-associated hemolytic uremic syndrome (Sp-HUS) is a serious and underdiagnosed deadly complication of invasive pneumococcal disease. Despite the introduction of the pneumococcal vaccine, cases of Sp-HUS continue to emerge, especially in children under the age of 2. While a lot has been studied regarding pneumococcal proteins and their role on Sp-HUS pathophysiology, little is known about the role of extracellular vesicles (EVs). In our work, we isolate and initially characterize EVs from a reference pathogenic strain (D39) and a strain isolated from a 2-year-old patient suffering from Sp-HUS. We demonstrate that despite lacking cytotoxicity toward human cells, Sp-HUS EVs are highly internalized by endothelial cells and can trigger cytokine and chemokine production in monocytes. In addition, this work specifically highlights the distinct morphological characteristics of Sp-HUS EVs and their unique cargo. Overall, this work sheds new light into potentially relevant players contained in EVs that might elucidate about pneumococcal EVs biogenesis or pose as interesting candidates for vaccine design.
Collapse
Affiliation(s)
- Miriana Battista
- Department of Infection Biology, Leibniz Institute for Natural Product Research and Infection Biology, Jena, Germany
| | - Bianca Hoffmann
- Applied Systems Biology, HKI-Center for Systems Biology of Infection, Leibniz Institute for Natural Product Research and Infection Biology, Hans Knöll Institute (HKI), Jena, Germany
| | - Yann Bachelot
- Applied Systems Biology, HKI-Center for Systems Biology of Infection, Leibniz Institute for Natural Product Research and Infection Biology, Hans Knöll Institute (HKI), Jena, Germany
| | - Lioba Zimmermann
- Department of Infection Biology, Leibniz Institute for Natural Product Research and Infection Biology, Jena, Germany
| | - Laura Teuber
- Department of Infection Biology, Leibniz Institute for Natural Product Research and Infection Biology, Jena, Germany
| | - Aurélie Jost
- Microverse Imaging Center, Cluster of Excellence “Balance of the Microverse,” Friedrich Schiller University, Jena, Germany
| | - Susanne Linde
- Center for Electron Microscopy, Jena University Hospital, Jena, Germany
| | - Martin Westermann
- Center for Electron Microscopy, Jena University Hospital, Jena, Germany
| | - Mario M. Müller
- Septomics Research Center, Jena University Hospital, Jena, Germany
| | - Hortense Slevogt
- Septomics Research Center, Jena University Hospital, Jena, Germany
| | - Sven Hammerschmidt
- Department of Molecular Genetics and Infection Biology, Interfaculty Institute for Genetics and Functional Genomics, Center for Functional Genomics of Microbes, University of Greifswald, Greifswald, Germany
| | - Marc Thilo Figge
- Applied Systems Biology, HKI-Center for Systems Biology of Infection, Leibniz Institute for Natural Product Research and Infection Biology, Hans Knöll Institute (HKI), Jena, Germany
- Faculty of Biological Sciences, Institute of Microbiology, Friedrich Schiller University, Jena, Germany
| | - Cláudia Vilhena
- Department of Infection Biology, Leibniz Institute for Natural Product Research and Infection Biology, Jena, Germany
| | - Peter F. Zipfel
- Department of Infection Biology, Leibniz Institute for Natural Product Research and Infection Biology, Jena, Germany
- Faculty of Biological Sciences, Institute of Microbiology, Friedrich Schiller University, Jena, Germany
| |
Collapse
|
9
|
Wen Z, Xia Y, Zhang Y, He Y, Niu C, Wu R, Zhang C, Jia C, Rong X, Chu M. SIGIRR-caspase-8 signaling mediates endothelial apoptosis in Kawasaki disease. Ital J Pediatr 2023; 49:2. [PMID: 36600293 PMCID: PMC9811794 DOI: 10.1186/s13052-022-01401-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/12/2022] [Accepted: 12/20/2022] [Indexed: 01/05/2023] Open
Abstract
BACKGROUND Kawasaki disease (KD) is a kind of vasculitis with unidentified etiology. Given that the current diagnosis and therapeutic strategy of KD are mainly dependent on clinical experiences, further research to explore its pathological mechanisms is warranted. METHODS Enzyme linked immunosorbent assay (ELISA) was used to measure the serum levels of SIGIRR, TLR4 and caspase-8. Western blotting was applied to determine protein levels, and flow cytometry was utilized to analyze cell apoptosis. Hematoxylin eosin (HE) staining and TUNEL staining were respectively used to observe coronary artery inflammation and DNA fragmentation. RESULTS In this study, we found the level of SIGIRR was downregulated in KD serum and KD serum-treated endothelial cells. However, the level of caspase-8 was increased in serum from KD patients compared with healthy control (HC). Therefore, we hypothesized that SIGIRR-caspase-8 signaling may play an essential role in KD pathophysiology. In vitro experiments demonstrated that endothelial cell apoptosis in the setting of KD was associated with caspase-8 activation, and SIGIRR overexpression alleviated endothelial cell apoptosis via inhibiting caspase-8 activation. These findings were also recapitulated in the Candida albicans cell wall extracts (CAWS)-induced KD mouse model. CONCLUSION Our data suggest that endothelial cell apoptosis mediated by SIGIRR-caspase-8 signaling plays a crucial role in coronary endothelial damage, providing potential targets to treat KD.
Collapse
Affiliation(s)
- Zhengwang Wen
- grid.417384.d0000 0004 1764 2632Children’s Heart Center, Institute of Cardiovascular Development and Translational Medicine, The Second Affiliated Hospital and Yuying Children’s Hospital of Wenzhou Medical University, 325027 Wenzhou, China ,grid.417384.d0000 0004 1764 2632Pediatric Research Institute, The Second Affiliated Hospital and Yuying Children’s Hospital of Wenzhou Medical University, Wenzhou, 325000 China ,Key Laboratory of Structural Malformations in Children of Zhejiang Province, Wenzhou, 325000 Zhejiang Province China
| | - Yuhan Xia
- grid.417384.d0000 0004 1764 2632Children’s Heart Center, Institute of Cardiovascular Development and Translational Medicine, The Second Affiliated Hospital and Yuying Children’s Hospital of Wenzhou Medical University, 325027 Wenzhou, China ,grid.417384.d0000 0004 1764 2632Pediatric Research Institute, The Second Affiliated Hospital and Yuying Children’s Hospital of Wenzhou Medical University, Wenzhou, 325000 China ,Key Laboratory of Structural Malformations in Children of Zhejiang Province, Wenzhou, 325000 Zhejiang Province China
| | - Yingying Zhang
- grid.417384.d0000 0004 1764 2632Children’s Heart Center, Institute of Cardiovascular Development and Translational Medicine, The Second Affiliated Hospital and Yuying Children’s Hospital of Wenzhou Medical University, 325027 Wenzhou, China ,grid.417384.d0000 0004 1764 2632Pediatric Research Institute, The Second Affiliated Hospital and Yuying Children’s Hospital of Wenzhou Medical University, Wenzhou, 325000 China ,Key Laboratory of Structural Malformations in Children of Zhejiang Province, Wenzhou, 325000 Zhejiang Province China
| | - Yuxi He
- grid.417384.d0000 0004 1764 2632Children’s Heart Center, Institute of Cardiovascular Development and Translational Medicine, The Second Affiliated Hospital and Yuying Children’s Hospital of Wenzhou Medical University, 325027 Wenzhou, China ,grid.417384.d0000 0004 1764 2632Pediatric Research Institute, The Second Affiliated Hospital and Yuying Children’s Hospital of Wenzhou Medical University, Wenzhou, 325000 China ,Key Laboratory of Structural Malformations in Children of Zhejiang Province, Wenzhou, 325000 Zhejiang Province China
| | - Chao Niu
- grid.417384.d0000 0004 1764 2632Pediatric Research Institute, The Second Affiliated Hospital and Yuying Children’s Hospital of Wenzhou Medical University, Wenzhou, 325000 China ,Key Laboratory of Structural Malformations in Children of Zhejiang Province, Wenzhou, 325000 Zhejiang Province China
| | - Rongzhou Wu
- grid.417384.d0000 0004 1764 2632Children’s Heart Center, Institute of Cardiovascular Development and Translational Medicine, The Second Affiliated Hospital and Yuying Children’s Hospital of Wenzhou Medical University, 325027 Wenzhou, China
| | - Chunxiang Zhang
- grid.417384.d0000 0004 1764 2632Children’s Heart Center, Institute of Cardiovascular Development and Translational Medicine, The Second Affiliated Hospital and Yuying Children’s Hospital of Wenzhou Medical University, 325027 Wenzhou, China
| | - Chang Jia
- grid.417384.d0000 0004 1764 2632Children’s Heart Center, Institute of Cardiovascular Development and Translational Medicine, The Second Affiliated Hospital and Yuying Children’s Hospital of Wenzhou Medical University, 325027 Wenzhou, China ,grid.417384.d0000 0004 1764 2632Pediatric Research Institute, The Second Affiliated Hospital and Yuying Children’s Hospital of Wenzhou Medical University, Wenzhou, 325000 China ,Key Laboratory of Structural Malformations in Children of Zhejiang Province, Wenzhou, 325000 Zhejiang Province China
| | - Xing Rong
- grid.417384.d0000 0004 1764 2632Children’s Heart Center, Institute of Cardiovascular Development and Translational Medicine, The Second Affiliated Hospital and Yuying Children’s Hospital of Wenzhou Medical University, 325027 Wenzhou, China
| | - Maoping Chu
- grid.417384.d0000 0004 1764 2632Children’s Heart Center, Institute of Cardiovascular Development and Translational Medicine, The Second Affiliated Hospital and Yuying Children’s Hospital of Wenzhou Medical University, 325027 Wenzhou, China ,grid.417384.d0000 0004 1764 2632Pediatric Research Institute, The Second Affiliated Hospital and Yuying Children’s Hospital of Wenzhou Medical University, Wenzhou, 325000 China ,Key Laboratory of Structural Malformations in Children of Zhejiang Province, Wenzhou, 325000 Zhejiang Province China
| |
Collapse
|
10
|
Bruggisser J, Iacovache I, Musson SC, Degiacomi MT, Posthaus H, Zuber B. Cryo-EM structure of the octameric pore of Clostridium perfringens β-toxin. EMBO Rep 2022; 23:e54856. [PMID: 36215680 PMCID: PMC9724662 DOI: 10.15252/embr.202254856] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2022] [Revised: 09/05/2022] [Accepted: 09/14/2022] [Indexed: 12/12/2022] Open
Abstract
Clostridium perfringens is one of the most widely distributed and successful pathogens producing an impressive arsenal of toxins. One of the most potent toxins produced is the C. perfringens β-toxin (CPB). This toxin is the main virulence factor of type C strains. We describe the cryo-electron microscopy (EM) structure of CPB oligomer. We show that CPB forms homo-octameric pores like the hetero-oligomeric pores of the bi-component leukocidins, with important differences in the receptor binding region and the N-terminal latch domain. Intriguingly, the octameric CPB pore complex contains a second 16-stranded β-barrel protrusion atop of the cap domain that is formed by the N-termini of the eight protomers. We propose that CPB, together with the newly identified Epx toxins, is a member a new subclass of the hemolysin-like family. In addition, we show that the β-barrel protrusion domain can be modified without affecting the pore-forming ability, thus making the pore particularly attractive for macromolecule sensing and nanotechnology. The cryo-EM structure of the octameric pore of CPB will facilitate future developments in both nanotechnology and basic research.
Collapse
Affiliation(s)
- Julia Bruggisser
- Institute of Animal Pathology, Vetsuisse‐FacultyUniversity of BernBernSwitzerland
| | - Ioan Iacovache
- Institute of Anatomy, Medical FacultyUniversity of BernBernSwitzerland
| | | | | | - Horst Posthaus
- Institute of Animal Pathology, Vetsuisse‐FacultyUniversity of BernBernSwitzerland
| | - Benoît Zuber
- Institute of Anatomy, Medical FacultyUniversity of BernBernSwitzerland
| |
Collapse
|
11
|
Xiong X, Tian S, Yang P, Lebreton F, Bao H, Sheng K, Yin L, Chen P, Zhang J, Qi W, Ruan J, Wu H, Chen H, Breault DT, Wu H, Earl AM, Gilmore MS, Abraham J, Dong M. Emerging enterococcus pore-forming toxins with MHC/HLA-I as receptors. Cell 2022; 185:1157-1171.e22. [PMID: 35259335 PMCID: PMC8978092 DOI: 10.1016/j.cell.2022.02.002] [Citation(s) in RCA: 17] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2021] [Revised: 12/15/2021] [Accepted: 02/01/2022] [Indexed: 01/12/2023]
Abstract
Enterococci are a part of human microbiota and a leading cause of multidrug resistant infections. Here, we identify a family of Enterococcus pore-forming toxins (Epxs) in E. faecalis, E. faecium, and E. hirae strains isolated across the globe. Structural studies reveal that Epxs form a branch of β-barrel pore-forming toxins with a β-barrel protrusion (designated the top domain) sitting atop the cap domain. Through a genome-wide CRISPR-Cas9 screen, we identify human leukocyte antigen class I (HLA-I) complex as a receptor for two members (Epx2 and Epx3), which preferentially recognize human HLA-I and homologous MHC-I of equine, bovine, and porcine, but not murine, origin. Interferon exposure, which stimulates MHC-I expression, sensitizes human cells and intestinal organoids to Epx2 and Epx3 toxicity. Co-culture with Epx2-harboring E. faecium damages human peripheral blood mononuclear cells and intestinal organoids, and this toxicity is neutralized by an Epx2 antibody, demonstrating the toxin-mediated virulence of Epx-carrying Enterococcus.
Collapse
Affiliation(s)
- Xiaozhe Xiong
- Department of Urology, Boston Children's Hospital, Department of Surgery, Harvard Medical School, Boston, MA 02115, USA; Department of Microbiology, Harvard Medical School, Boston, MA 02115, USA
| | - Songhai Tian
- Department of Urology, Boston Children's Hospital, Department of Surgery, Harvard Medical School, Boston, MA 02115, USA; Department of Microbiology, Harvard Medical School, Boston, MA 02115, USA
| | - Pan Yang
- Department of Microbiology, Harvard Medical School, Boston, MA 02115, USA
| | - Francois Lebreton
- Department of Microbiology, Harvard Medical School, Boston, MA 02115, USA; Department of Ophthalmology, Harvard Medical School, Massachusetts Eye and Ear Infirmary, Boston, MA 02114, USA; Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA; Multidrug-Resistant Organism Repository and Surveillance Network (MRSN), Walter Reed Army Institute of Research, Silver Spring, MD 20910, USA
| | - Huan Bao
- Department of Molecular Medicine, The Scripps Research Institute, Jupiter, FL 33458, USA
| | - Kuanwei Sheng
- Wyss Institute for Biologically Inspired Engineering, Harvard University, Boston, MA 02115
| | - Linxiang Yin
- Department of Urology, Boston Children's Hospital, Department of Surgery, Harvard Medical School, Boston, MA 02115, USA; Department of Microbiology, Harvard Medical School, Boston, MA 02115, USA
| | - Pengsheng Chen
- Department of Urology, Boston Children's Hospital, Department of Surgery, Harvard Medical School, Boston, MA 02115, USA; Department of Microbiology, Harvard Medical School, Boston, MA 02115, USA
| | - Jie Zhang
- Department of Urology, Boston Children's Hospital, Department of Surgery, Harvard Medical School, Boston, MA 02115, USA
| | - Wanshu Qi
- Division of Endocrinology, Boston Children's Hospital, and Department of Pediatrics, Harvard Medical School, Boston, MA 02115, USA
| | - Jianbin Ruan
- Program in Cellular and Molecular Medicine, Boston Children's Hospital, and Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, Boston, MA 02115, USA; Department of Immunology, University of Connecticut Health School of Medicine, Farmington, CT 06030, USA
| | - Hao Wu
- Vascular Biology Program, Department of Surgery, Boston Children's Hospital and Harvard Medical School, Boston, MA 02115, USA
| | - Hong Chen
- Vascular Biology Program, Department of Surgery, Boston Children's Hospital and Harvard Medical School, Boston, MA 02115, USA
| | - David T Breault
- Division of Endocrinology, Boston Children's Hospital, and Department of Pediatrics, Harvard Medical School, Boston, MA 02115, USA; Harvard Stem Cell Institute, Cambridge, MA 02138, USA
| | - Hao Wu
- Program in Cellular and Molecular Medicine, Boston Children's Hospital, and Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, Boston, MA 02115, USA
| | - Ashlee M Earl
- Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA
| | - Michael S Gilmore
- Department of Microbiology, Harvard Medical School, Boston, MA 02115, USA; Department of Ophthalmology, Harvard Medical School, Massachusetts Eye and Ear Infirmary, Boston, MA 02114, USA; Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA.
| | - Jonathan Abraham
- Department of Microbiology, Harvard Medical School, Boston, MA 02115, USA; Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA; Division of Infectious Diseases, Department of Medicine, Brigham and Women's Hospital, Boston, MA 02115, USA.
| | - Min Dong
- Department of Urology, Boston Children's Hospital, Department of Surgery, Harvard Medical School, Boston, MA 02115, USA; Department of Microbiology, Harvard Medical School, Boston, MA 02115, USA.
| |
Collapse
|
12
|
Ulhuq FR, Mariano G. Bacterial pore-forming toxins. MICROBIOLOGY (READING, ENGLAND) 2022; 168:001154. [PMID: 35333704 PMCID: PMC9558359 DOI: 10.1099/mic.0.001154] [Citation(s) in RCA: 19] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/25/2021] [Accepted: 02/03/2022] [Indexed: 12/11/2022]
Abstract
Pore-forming toxins (PFTs) are widely distributed in both Gram-negative and Gram-positive bacteria. PFTs can act as virulence factors that bacteria utilise in dissemination and host colonisation or, alternatively, they can be employed to compete with rival microbes in polymicrobial niches. PFTs transition from a soluble form to become membrane-embedded by undergoing large conformational changes. Once inserted, they perforate the membrane, causing uncontrolled efflux of ions and/or nutrients and dissipating the protonmotive force (PMF). In some instances, target cells intoxicated by PFTs display additional effects as part of the cellular response to pore formation. Significant progress has been made in the mechanistic description of pore formation for the different PFTs families, but in several cases a complete understanding of pore structure remains lacking. PFTs have evolved recognition mechanisms to bind specific receptors that define their host tropism, although this can be remarkably diverse even within the same family. Here we summarise the salient features of PFTs and highlight where additional research is necessary to fully understand the mechanism of pore formation by members of this diverse group of protein toxins.
Collapse
Affiliation(s)
- Fatima R. Ulhuq
- Microbes in Health and Disease Theme, Newcastle University Biosciences Institute, Newcastle University, Newcastle upon Tyne, UK
| | - Giuseppina Mariano
- Microbes in Health and Disease Theme, Newcastle University Biosciences Institute, Newcastle University, Newcastle upon Tyne, UK
| |
Collapse
|
13
|
Liao D, Sundlov J, Zhu J, Mei H, Hu Y, Newman DK, Newman PJ. Atomic Level Dissection of the Platelet Endothelial Cell Adhesion Molecule 1 (PECAM-1) Homophilic Binding Interface: Implications for Endothelial Cell Barrier Function. Arterioscler Thromb Vasc Biol 2022; 42:193-204. [PMID: 34937389 PMCID: PMC8942131 DOI: 10.1161/atvbaha.121.316668] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
OBJECTIVE PECAM-1 (platelet endothelial cell adhesion molecule 1) is a 130 kDa member of the immunoglobulin (Ig) gene superfamily that is expressed on the surfaces of platelets and leukocytes and concentrated at the intercellular junctions of confluent endothelial cell monolayers. PECAM-1 Ig domains 1 and 2 (IgD1 and IgD2) engage in homophilic interactions that support a host of vascular functions, including support of leukocyte transendothelial migration and the maintenance of endothelial junctional integrity. The recently solved crystal structure of PECAM-1 IgD1 and IgD2 revealed a number of intermolecular interfaces predicted to play important roles in stabilizing PECAM-1/PECAM-1 homophilic interactions and in formation and maintenance of endothelial cell-cell contacts. We sought to determine whether the protein interfaces implicated in the crystal structure reflect physiologically important interactions. Approach and Results: We assessed the impact of single amino acid substitutions at the interfaces between opposing PECAM-1 molecules on homophilic binding and endothelial cell function. Substitution of key residues within the IgD1-IgD1 and IgD1-IgD2 interfaces but not those within the smaller IgD2-IgD2 interface, markedly disrupted PECAM-1 homophilic binding and its downstream effector functions, including the ability of PECAM-1 to localize at endothelial cell-cell borders, mediate the formation of endothelial tubes, and restore endothelial barrier integrity. CONCLUSIONS Taken together, these results validate the recently described PECAM-1 IgD1/IgD2 crystal structure by demonstrating that specific residues visualized within the IgD1-IgD1 and IgD1-IgD2 interfaces of opposing molecules in the crystal are required for functionally important homophilic interactions. This information can now be exploited to modulate functions of PECAM-1 in vivo.
Collapse
Affiliation(s)
- Danying Liao
- Blood Research Institute, Versiti Blood Center of Wisconsin, Milwaukee, WI,Institute of Hematology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430022, China
| | - Jesse Sundlov
- Blood Research Institute, Versiti Blood Center of Wisconsin, Milwaukee, WI
| | - Jieqing Zhu
- Blood Research Institute, Versiti Blood Center of Wisconsin, Milwaukee, WI,Department of Biochemistry, Medical College of Wisconsin, Milwaukee
| | - Heng Mei
- Institute of Hematology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430022, China
| | - Yu Hu
- Institute of Hematology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430022, China
| | - Debra K. Newman
- Blood Research Institute, Versiti Blood Center of Wisconsin, Milwaukee, WI,Department of Pharmacology, Medical College of Wisconsin, Milwaukee,Department of Microbiology Medical College of Wisconsin, Milwaukee,Department of The Cardiovascular Center, Medical College of Wisconsin, Milwaukee
| | - Peter J. Newman
- Blood Research Institute, Versiti Blood Center of Wisconsin, Milwaukee, WI,Institute of Hematology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430022, China,Department of Pharmacology, Medical College of Wisconsin, Milwaukee,Department of Cell Biology, Neurobiology and Anatomy, Medical College of Wisconsin, Milwaukee,Department of The Cardiovascular Center, Medical College of Wisconsin, Milwaukee
| |
Collapse
|
14
|
Platelet Endothelial Cell Adhesion Molecule 1 (CD31) Is Essential for Clostridium perfringens Beta-Toxin Mediated Cytotoxicity in Human Endothelial and Monocytic Cells. Toxins (Basel) 2021; 13:toxins13120893. [PMID: 34941730 PMCID: PMC8703487 DOI: 10.3390/toxins13120893] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2021] [Revised: 12/08/2021] [Accepted: 12/10/2021] [Indexed: 11/17/2022] Open
Abstract
Beta toxin (CPB) is a small hemolysin beta pore-forming toxin (β-PFT) produced by Clostridium perfringens type C. It plays a central role in the pathogenesis of necro-hemorrhagic enteritis in young animals and humans via targeting intestinal endothelial cells. We recently identified the membrane protein CD31 (PECAM-1) as the receptor for CPB on mouse endothelial cells. We now assess the role of CD31 in CPB cytotoxicity against human endothelial and monocytic cells using a CRISPR/Cas9 gene knockout and an antibody blocking approach. CD31 knockout human endothelial and monocytic cells were resistant to CPB and CPB oligomers only formed in CD31-expressing cells. CD31 knockout endothelial and monocytic cells could be selectively enriched out of a polyclonal cell population by exposing them to CPB. Moreover, antibody mediated blocking of the extracellular Ig6 domain of CD31 abolished CPB cytotoxicity and oligomer formation in endothelial and monocytic cells. In conclusion, this study confirms the role of CD31 as a receptor of CPB on human endothelial and monocytic cells. Specific interaction with the CD31 molecule can thus explain the cell type specificity of CPB observed in vitro and corresponds to in vivo observations in naturally diseased animals.
Collapse
|
15
|
Mehdizadeh Gohari I, A. Navarro M, Li J, Shrestha A, Uzal F, A. McClane B. Pathogenicity and virulence of Clostridium perfringens. Virulence 2021; 12:723-753. [PMID: 33843463 PMCID: PMC8043184 DOI: 10.1080/21505594.2021.1886777] [Citation(s) in RCA: 85] [Impact Index Per Article: 28.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2020] [Revised: 01/25/2021] [Accepted: 01/29/2021] [Indexed: 12/11/2022] Open
Abstract
Clostridium perfringens is an extremely versatile pathogen of humans and livestock, causing wound infections like gas gangrene (clostridial myonecrosis), enteritis/enterocolitis (including one of the most common human food-borne illnesses), and enterotoxemia (where toxins produced in the intestine are absorbed and damage distant organs such as the brain). The virulence of this Gram-positive, spore-forming, anaerobe is largely attributable to its copious toxin production; the diverse actions and roles in infection of these toxins are now becoming established. Most C. perfringens toxin genes are encoded on conjugative plasmids, including the pCW3-like and the recently discovered pCP13-like plasmid families. Production of C. perfringens toxins is highly regulated via processes involving two-component regulatory systems, quorum sensing and/or sporulation-related alternative sigma factors. Non-toxin factors, such as degradative enzymes like sialidases, are also now being implicated in the pathogenicity of this bacterium. These factors can promote toxin action in vitro and, perhaps in vivo, and also enhance C. perfringens intestinal colonization, e.g. NanI sialidase increases C. perfringens adherence to intestinal tissue and generates nutrients for its growth, at least in vitro. The possible virulence contributions of many other factors, such as adhesins, the capsule and biofilms, largely await future study.
Collapse
Affiliation(s)
- Iman Mehdizadeh Gohari
- Department of Microbiology and Molecular Genetics, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
| | - Mauricio A. Navarro
- California Animal Health and Food Safety Laboratory, School of Veterinary Medicine, University of California Davis, San Bernardino, CA, USA
| | - Jihong Li
- Department of Microbiology and Molecular Genetics, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
| | - Archana Shrestha
- Department of Microbiology and Molecular Genetics, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
| | - Francisco Uzal
- California Animal Health and Food Safety Laboratory, School of Veterinary Medicine, University of California Davis, San Bernardino, CA, USA
| | - Bruce A. McClane
- Department of Microbiology and Molecular Genetics, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
| |
Collapse
|
16
|
Deutschmann S, Rimle L, von Ballmoos C. Rapid Estimation of Membrane Protein Orientation in Liposomes. Chembiochem 2021; 23:e202100543. [PMID: 34763366 PMCID: PMC9299231 DOI: 10.1002/cbic.202100543] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2021] [Revised: 11/11/2021] [Indexed: 11/25/2022]
Abstract
The topological organization of proteins embedded in biological membranes is crucial for the tight interplay between these enzymes and their accessibility to substrates in order to fulfil enzymatic activity. The orientation of a membrane protein reconstituted in artificial membranes depends on many parameters and is hardly predictable. Here, we present a convenient approach to assess this important property independent of the enzymatic activity of the reconstituted protein. Based on cysteine‐specific chemical modification of a target membrane protein with a cyanine fluorophore and a corresponding membrane‐impermeable fluorescence quencher, the novel strategy allows rapid evaluation of the distribution of the two orientations after reconstitution. The assay has been tested for the respiratory complexes bo3 oxidase and ATP synthase of Escherichia coli and the results agree well with other orientation determination approaches. Given the simple procedure, the proposed method is a powerful tool for optimization of reconstitution conditions or quantitative orientation information prior to functional measurements.
Collapse
Affiliation(s)
- Sabina Deutschmann
- Department of Chemistry, Biochemistry and Pharmaceutical Sciences, University of Bern, Freiestrasse 3, 3012, Bern, Switzerland.,Graduate School for Cellular and Biomedical Sciences, University of Bern, 3012, Bern, Switzerland
| | - Lukas Rimle
- Department of Chemistry, Biochemistry and Pharmaceutical Sciences, University of Bern, Freiestrasse 3, 3012, Bern, Switzerland.,Graduate School for Cellular and Biomedical Sciences, University of Bern, 3012, Bern, Switzerland
| | - Christoph von Ballmoos
- Department of Chemistry, Biochemistry and Pharmaceutical Sciences, University of Bern, Freiestrasse 3, 3012, Bern, Switzerland
| |
Collapse
|
17
|
Application of the MISTEACHING(S) disease susceptibility framework to Actinobacillus pleuropneumoniae to identify research gaps: an exemplar of a veterinary pathogen. Anim Health Res Rev 2021; 22:120-135. [PMID: 34275511 DOI: 10.1017/s1466252321000074] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Historically, the MISTEACHING (microbiome, immunity, sex, temperature, environment, age, chance, history, inoculum, nutrition, genetics) framework to describe the outcome of host-pathogen interaction, has been applied to human pathogens. Here, we show, using Actinobacillus pleuropneumoniae as an exemplar, that the MISTEACHING framework can be applied to a strict veterinary pathogen, enabling the identification of major research gaps, the formulation of hypotheses whose study will lead to a greater understanding of pathogenic mechanisms, and/or improved prevention/therapeutic measures. We also suggest that the MISTEACHING framework should be extended with the inclusion of a 'strain' category, to become MISTEACHINGS. We conclude that the MISTEACHINGS framework can be applied to veterinary pathogens, whether they be bacteria, fungi, viruses, or parasites, and hope to stimulate others to use it to identify research gaps and to formulate hypotheses worthy of study with their own pathogens.
Collapse
|
18
|
An optimized confocal intravital microscopy protocol for long-term live imaging of murine F-actin organization during naïve lymphocyte migration. STAR Protoc 2021; 2:100498. [PMID: 34195670 PMCID: PMC8225983 DOI: 10.1016/j.xpro.2021.100498] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
Actin plays a crucial role during cell motility, but the organization of F-actin filaments during lymphocyte migration has not been visualized in vivo. Here, we present a 4D imaging platform using high-resolution confocal intravital microscopy to precisely determine the F-actin filament profile during lymphocyte transendothelial migration and interstitial migration. This protocol allows prolonged live imaging by laser scanning microscopy with advanced spatial resolution compared with the traditional multi-photon intravital microscopy techniques. For complete details on the use and execution of this protocol, please refer to Yan et al. (2019).
Collapse
|
19
|
Dong X, Zhang M, Jin X. A Potential Filling Material for Wound Healing and Shaping: Acellular Dermal Matrix Combined with Autologous Dermis. Aesthetic Plast Surg 2021; 46:190-191. [PMID: 33973047 DOI: 10.1007/s00266-021-02343-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2021] [Accepted: 04/28/2021] [Indexed: 11/30/2022]
Affiliation(s)
- Xinhang Dong
- Plastic Surgery Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China
| | - Mingzi Zhang
- Department of Plastic Surgery, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China
| | - Xiaolei Jin
- Plastic Surgery Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China.
| |
Collapse
|
20
|
Innovative and Highly Sensitive Detection of Clostridium perfringens Enterotoxin Based on Receptor Interaction and Monoclonal Antibodies. Toxins (Basel) 2021; 13:toxins13040266. [PMID: 33917845 PMCID: PMC8068247 DOI: 10.3390/toxins13040266] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2021] [Revised: 04/03/2021] [Accepted: 04/06/2021] [Indexed: 11/16/2022] Open
Abstract
Clostridium perfringens enterotoxin (CPE) regularly causes food poisoning and antibiotic-associated diarrhea; therefore, reliable toxin detection is crucial. To this aim, we explored stationary and mobile strategies to detect CPE either exclusively by monoclonal antibodies (mAbs) or, alternatively, by toxin-enrichment via the cellular receptor of CPE, claudin-4, and mAb detection. Among the newly generated mAbs, we identified nine CPE-specific mAbs targeting five distinct epitopes, among them mAbs recognizing CPE bound to claudin-4 or neutralizing CPE activity in vitro. In surface plasmon resonance experiments, all mAbs and claudin-4 revealed excellent affinities towards CPE, ranging from 0.05 to 2.3 nM. Integrated into sandwich enzyme-linked immunosorbent assays (ELISAs), the most sensitive mAb/mAb and claudin-4/mAb combinations achieved similar detection limits of 0.3 pg/mL and 1.0 pg/mL, respectively, specifically detecting recombinant CPE from spiked feces and native CPE from 30 different C. perfringens culture supernatants. The implementation of mAb- and receptor-based ELISAs into a mobile detection platform enabled the fast detection of CPE, which will be helpful in clinical laboratories to diagnose diarrhea of assumed bacterial origin. In conclusion, we successfully employed an endogenous receptor and novel high affinity mAbs for highly sensitive and specific CPE-detection. These tools will be useful for both basic and applied research.
Collapse
|
21
|
Su K, Wang J, Lv Y, Tian M, Zhao YY, Minshall RD, Hu G. YAP expression in endothelial cells prevents ventilator-induced lung injury. Am J Physiol Lung Cell Mol Physiol 2021; 320:L568-L582. [PMID: 33565367 DOI: 10.1152/ajplung.00472.2020] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
Ventilator-induced lung injury is associated with an increase in mortality in patients with respiratory dysfunction, although mechanical ventilation is an essential intervention implemented in the intensive care unit. Intrinsic molecular mechanisms for minimizing lung inflammatory injury during mechanical ventilation remain poorly defined. We hypothesize that Yes-associated protein (YAP) expression in endothelial cells protects the lung against ventilator-induced injury. Wild-type and endothelial-specific YAP-deficient mice were subjected to a low (7 mL/kg) or high (21 mL/kg) tidal volume (VT) ventilation for 4 h. Infiltration of inflammatory cells into the lung, vascular permeability, lung histopathology, and the levels of inflammatory cytokines were measured. Here, we showed that mechanical ventilation with high VT upregulated YAP protein expression in pulmonary endothelial cells. Endothelial-specific YAP knockout mice following high VT ventilation exhibited increased neutrophil counts and protein content in bronchoalveolar lavage fluid, Evans blue leakage, and histological lung injury compared with wild-type littermate controls. Deletion of YAP in endothelial cells exaggerated vascular endothelial (VE)-cadherin phosphorylation, downregulation of vascular endothelial protein tyrosine phosphatase (VE-PTP), and dissociation of VE-cadherin and catenins following mechanical ventilation. Importantly, exogenous expression of wild-type VE-PTP in the pulmonary vasculature rescued YAP ablation-induced increases in neutrophil counts and protein content in bronchoalveolar lavage fluid, vascular leakage, and histological lung injury as well as VE-cadherin phosphorylation and dissociation from catenins following ventilation. These data demonstrate that YAP expression in endothelial cells suppresses lung inflammatory response and edema formation by modulating VE-PTP-mediated VE-cadherin phosphorylation and thus plays a protective role in ventilator-induced lung injury.
Collapse
Affiliation(s)
- Kai Su
- Department of Anesthesiology, University of Illinois College of Medicine, Chicago, Illinois.,Department of Anesthesiology, Beijing Friendship Hospital, Capital Medical University, Beijing, China
| | - Jianguo Wang
- Department of Anesthesiology, University of Illinois College of Medicine, Chicago, Illinois.,Department of Anesthesiology, Affiliated Hospital of Jining Medical University, Shandong, China
| | - Yang Lv
- Department of Anesthesiology, University of Illinois College of Medicine, Chicago, Illinois
| | - Ming Tian
- Department of Anesthesiology, Beijing Friendship Hospital, Capital Medical University, Beijing, China
| | - You-Yang Zhao
- Program for Lung and Vascular Biology, Stanley Manne Children's Research Institute, Ann & Robert H. Lurie Children's Hospital of Chicago, Chicago, Illinois.,Division of Critical Care, Department of Pediatrics, Northwestern University Feinberg School of Medicine, Chicago, Illinois
| | - Richard D Minshall
- Department of Anesthesiology, University of Illinois College of Medicine, Chicago, Illinois.,Department of Pharmacology, University of Illinois College of Medicine, Chicago, Illinois
| | - Guochang Hu
- Department of Anesthesiology, University of Illinois College of Medicine, Chicago, Illinois.,Department of Pharmacology, University of Illinois College of Medicine, Chicago, Illinois
| |
Collapse
|
22
|
Li Y, Li Y, Mengist HM, Shi C, Zhang C, Wang B, Li T, Huang Y, Xu Y, Jin T. Structural Basis of the Pore-Forming Toxin/Membrane Interaction. Toxins (Basel) 2021; 13:toxins13020128. [PMID: 33572271 PMCID: PMC7914777 DOI: 10.3390/toxins13020128] [Citation(s) in RCA: 21] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2020] [Revised: 01/13/2021] [Accepted: 02/02/2021] [Indexed: 12/14/2022] Open
Abstract
With the rapid growth of antibiotic-resistant bacteria, it is urgent to develop alternative therapeutic strategies. Pore-forming toxins (PFTs) belong to the largest family of virulence factors of many pathogenic bacteria and constitute the most characterized classes of pore-forming proteins (PFPs). Recent studies revealed the structural basis of several PFTs, both as soluble monomers, and transmembrane oligomers. Upon interacting with host cells, the soluble monomer of bacterial PFTs assembles into transmembrane oligomeric complexes that insert into membranes and affect target cell-membrane permeability, leading to diverse cellular responses and outcomes. Herein we have reviewed the structural basis of pore formation and interaction of PFTs with the host cell membrane, which could add valuable contributions in comprehensive understanding of PFTs and searching for novel therapeutic strategies targeting PFTs and interaction with host receptors in the fight of bacterial antibiotic-resistance.
Collapse
Affiliation(s)
- Yajuan Li
- Department of Clinical Laboratory, the First Affiliated Hospital of Anhui Medical University, Hefei 230022, China; (Y.L.); (C.S.); (B.W.); (T.L.); (Y.H.)
| | - Yuelong Li
- Hefei National Laboratory for Physical Sciences at Microscale, Laboratory of Structural Immunology, CAS Key Laboratory of Innate Immunity and Chronic Disease, Division of Life Sciences and Medicine, School of Basic Medical Sciences, University of Science and Technology of China, Hefei 230027, China; (Y.L.); (H.M.M.); (C.Z.)
| | - Hylemariam Mihiretie Mengist
- Hefei National Laboratory for Physical Sciences at Microscale, Laboratory of Structural Immunology, CAS Key Laboratory of Innate Immunity and Chronic Disease, Division of Life Sciences and Medicine, School of Basic Medical Sciences, University of Science and Technology of China, Hefei 230027, China; (Y.L.); (H.M.M.); (C.Z.)
| | - Cuixiao Shi
- Department of Clinical Laboratory, the First Affiliated Hospital of Anhui Medical University, Hefei 230022, China; (Y.L.); (C.S.); (B.W.); (T.L.); (Y.H.)
| | - Caiying Zhang
- Hefei National Laboratory for Physical Sciences at Microscale, Laboratory of Structural Immunology, CAS Key Laboratory of Innate Immunity and Chronic Disease, Division of Life Sciences and Medicine, School of Basic Medical Sciences, University of Science and Technology of China, Hefei 230027, China; (Y.L.); (H.M.M.); (C.Z.)
| | - Bo Wang
- Department of Clinical Laboratory, the First Affiliated Hospital of Anhui Medical University, Hefei 230022, China; (Y.L.); (C.S.); (B.W.); (T.L.); (Y.H.)
| | - Tingting Li
- Department of Clinical Laboratory, the First Affiliated Hospital of Anhui Medical University, Hefei 230022, China; (Y.L.); (C.S.); (B.W.); (T.L.); (Y.H.)
| | - Ying Huang
- Department of Clinical Laboratory, the First Affiliated Hospital of Anhui Medical University, Hefei 230022, China; (Y.L.); (C.S.); (B.W.); (T.L.); (Y.H.)
| | - Yuanhong Xu
- Department of Clinical Laboratory, the First Affiliated Hospital of Anhui Medical University, Hefei 230022, China; (Y.L.); (C.S.); (B.W.); (T.L.); (Y.H.)
- Correspondence: (Y.X.); (T.J.); Tel.: +86-13505694447 (Y.X.); +86-17605607323 (T.J.)
| | - Tengchuan Jin
- Hefei National Laboratory for Physical Sciences at Microscale, Laboratory of Structural Immunology, CAS Key Laboratory of Innate Immunity and Chronic Disease, Division of Life Sciences and Medicine, School of Basic Medical Sciences, University of Science and Technology of China, Hefei 230027, China; (Y.L.); (H.M.M.); (C.Z.)
- Correspondence: (Y.X.); (T.J.); Tel.: +86-13505694447 (Y.X.); +86-17605607323 (T.J.)
| |
Collapse
|
23
|
Song N, Chen L, Ren X, Waterfield NR, Yang J, Yang G. N-Glycans and sulfated glycosaminoglycans contribute to the action of diverse Tc toxins on mammalian cells. PLoS Pathog 2021; 17:e1009244. [PMID: 33539469 PMCID: PMC7861375 DOI: 10.1371/journal.ppat.1009244] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2020] [Accepted: 12/18/2020] [Indexed: 01/11/2023] Open
Abstract
Tc toxin is an exotoxin composed of three subunits named TcA, TcB and TcC. Structural analysis revealed that TcA can form homopentamer that mediates the cellular recognition and delivery processes, thus contributing to the host tropism of Tc toxin. N-glycans and heparan sulfates have been shown to act as receptors for several Tc toxins. Here, we performed two independent genome-wide CRISPR-Cas9 screens, and have validated glycans and sulfated glycosaminoglycans (sGAGs) as Tc toxin receptors also for previously uncharacterized Tc toxins. We found that TcdA1 form Photorhabdus luminescens W14 (TcdA1W14) can recognize N-glycans via the RBD-D domain, corroborating previous findings. Knockout of N-glycan processing enzymes specifically blocks the intoxication of TcdA1W14-assembled Tc toxin. On the other hand, our results showed that sGAG biosynthesis pathway is involved in the cell surface binding of TcdA2TT01 (TcdA2 from P. luminescens TT01). Competition assays and biolayer interferometry demonstrated that the sulfation group in sGAGs is required for the binding of TcdA2TT01. Finally, based on the conserved domains of representative TcA proteins, we have identified 1,189 putative TcAs from 1,039 bacterial genomes. These TcAs are categorized into five subfamilies. Each subfamily shows a good correlation with both genetic organization of the TcA protein(s) and taxonomic origin of the genomes, suggesting these subfamilies may utilize different mechanisms for cellular recognition. Taken together, our results support the previously described two different binding modalities of Tc toxins, leading to unique host targeting properties. We also present the bioinformatics data and receptor screening strategies for TcA proteins, provide new insights into understanding host specificity and biomedical applications of Tc toxins. The Toxin complexes, also referred to as Tc toxins, are a family of A5BC exotoxins widely distributed among Gram-negative and positive bacteria. First identified in Entomopathogenic bacteria as key virulence factors to combat insect hosts, putative Tc toxin loci are also encoded by a range of human pathogens such as Salmonella and Yersinia. Previous studies indicated that several Tc toxins can target invertebrate and vertebrate cells via binding with N-glycans and heparan sulfates. Here our genome-wide CRISPR-Cas9 screens validated that different Tc toxins utilized distinct receptors for the adhesion to their targets, which is determined by TcA homopentamer. For example, TcdA1 from Photorhabdus luminescens W14 (TcdA1W14) relies on N-glycan binding to exert its toxic effects, while sulfate groups of sulfated glycosaminoglycans are critical for the cell targeting of other TcAs such as TcdA2TT01 (TcdA2 from P. luminescens TT01). Consistent with the previously described different binding modalities of Tc toxins, our results confirm that the receptor selectivity of TcAs contribute to the cellular tropism of Tc toxins. Furthermore we has also identified 1,189 TcA homologues and categorized them into five subfamilies. Each TcA subfamily shows a good correlation with the taxonomic origin of the genomes, suggesting these subfamilies are linked to diverse host tropisms via different binding modalities. Together, our findings provide mechanistic insights into understanding host specificity of distinct Tc toxins and the development of therapeutics for Tc toxin-related infections, as well as the adaptation of Tc-injectisomes as potential biotechnology tools and pest-control weapons.
Collapse
Affiliation(s)
- Nan Song
- Beijing Institute of Tropical Medicine, Beijing Friendship Hospital, Capital Medical University, Beijing, China
- Emergency and Critical Care Center, Beijing Friendship Hospital, Capital Medical University, Beijing, China
| | - Lihong Chen
- NHC Key Laboratory of Systems Biology of Pathogens, Institute of Pathogen Biology, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China
| | - Xingmei Ren
- Beijing Institute of Tropical Medicine, Beijing Friendship Hospital, Capital Medical University, Beijing, China
- Emergency and Critical Care Center, Beijing Friendship Hospital, Capital Medical University, Beijing, China
| | | | - Jian Yang
- NHC Key Laboratory of Systems Biology of Pathogens, Institute of Pathogen Biology, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China
| | - Guowei Yang
- Beijing Institute of Tropical Medicine, Beijing Friendship Hospital, Capital Medical University, Beijing, China
- Emergency and Critical Care Center, Beijing Friendship Hospital, Capital Medical University, Beijing, China
- * E-mail:
| |
Collapse
|
24
|
Spatiotemporal Regulation of Vibrio Exotoxins by HlyU and Other Transcriptional Regulators. Toxins (Basel) 2020; 12:toxins12090544. [PMID: 32842612 PMCID: PMC7551375 DOI: 10.3390/toxins12090544] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2020] [Revised: 08/17/2020] [Accepted: 08/19/2020] [Indexed: 02/06/2023] Open
Abstract
After invading a host, bacterial pathogens secrete diverse protein toxins to disrupt host defense systems. To ensure successful infection, however, pathogens must precisely regulate the expression of those exotoxins because uncontrolled toxin production squanders energy. Furthermore, inappropriate toxin secretion can trigger host immune responses that are detrimental to the invading pathogens. Therefore, bacterial pathogens use diverse transcriptional regulators to accurately regulate multiple exotoxin genes based on spatiotemporal conditions. This review covers three major exotoxins in pathogenic Vibrio species and their transcriptional regulation systems. When Vibrio encounters a host, genes encoding cytolysin/hemolysin, multifunctional-autoprocessing repeats-in-toxin (MARTX) toxin, and secreted phospholipases are coordinately regulated by the transcriptional regulator HlyU. At the same time, however, they are distinctly controlled by a variety of other transcriptional regulators. How this coordinated but distinct regulation of exotoxins makes Vibrio species successful pathogens? In addition, anti-virulence strategies that target the coordinating master regulator HlyU and related future research directions are discussed.
Collapse
|
25
|
Lencer WI. Everything Illuminated-Clostridium perfringens β-toxin. Cell Host Microbe 2020; 28:5-6. [PMID: 32645353 DOI: 10.1016/j.chom.2020.06.006] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
Abstract
In this issue of Cell Host & Microbe, Bruggisser et al. show that Clostridium perfringens β-toxin (CPB) binds platelet endothelial cell adhesion molecule-1 (PECAM-1) (also known as CD31) to induce membrane pores. The discovery explains the cell type specificity for CPB and, in large part, the basic pathophysiology of disease.
Collapse
Affiliation(s)
- Wayne I Lencer
- Boston Children's Hospital, Boston, MA 02115, USA; Harvard Medical School, Boston, MA 02115, USA; Harvard Digestive Disease Center, Boston, MA 02115, USA.
| |
Collapse
|