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Pourliotopoulou E, Karampatakis T, Kachrimanidou M. Exploring the Toxin-Mediated Mechanisms in Clostridioides difficile Infection. Microorganisms 2024; 12:1004. [PMID: 38792835 DOI: 10.3390/microorganisms12051004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2024] [Revised: 05/14/2024] [Accepted: 05/15/2024] [Indexed: 05/26/2024] Open
Abstract
Clostridioides difficile infection (CDI) is the leading cause of nosocomial antibiotic-associated diarrhea, and colitis, with increasing incidence and healthcare costs. Its pathogenesis is primarily driven by toxins produced by the bacterium C. difficile, Toxin A (TcdA) and Toxin B (TcdB). Certain strains produce an additional toxin, the C. difficile transferase (CDT), which further enhances the virulence and pathogenicity of C. difficile. These toxins disrupt colonic epithelial barrier integrity, and induce inflammation and cellular damage, leading to CDI symptoms. Significant progress has been made in the past decade in elucidating the molecular mechanisms of TcdA, TcdB, and CDT, which provide insights into the management of CDI and the future development of novel treatment strategies based on anti-toxin therapies. While antibiotics are common treatments, high recurrence rates necessitate alternative therapies. Bezlotoxumab, targeting TcdB, is the only available anti-toxin, yet limitations persist, prompting ongoing research. This review highlights the current knowledge of the structure and mechanism of action of C. difficile toxins and their role in disease. By comprehensively describing the toxin-mediated mechanisms, this review provides insights for the future development of novel treatment strategies and the management of CDI.
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Affiliation(s)
- Evdokia Pourliotopoulou
- Department of Microbiology, Medical School, Aristotle University of Thessaloniki, 541 24 Thessaloniki, Greece
| | | | - Melania Kachrimanidou
- Department of Microbiology, Medical School, Aristotle University of Thessaloniki, 541 24 Thessaloniki, Greece
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Zheng Y, Yang Q, Luo J, Zhang Y, Li X, He L, Ma C, Tao L. Identification of a hemorrhagic determinant in Clostridioides difficile TcdA and Paeniclostridium sordellii TcsH. Microbiol Spectr 2024:e0035424. [PMID: 38709085 DOI: 10.1128/spectrum.00354-24] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2024] [Accepted: 04/18/2024] [Indexed: 05/07/2024] Open
Abstract
Paeniclostridium sordellii hemorrhagic toxin (TcsH) and Clostridioides difficile toxin A (TcdA) are two major members of the large clostridial toxin (LCT) family. These two toxins share ~87% similarity and are known to cause severe hemorrhagic pathology in animals. Yet, the pathogenesis of their hemorrhagic toxicity has been mysterious for decades. Here, we examined the liver injury after systemic exposure to different LCTs and found that only TcsH and TcdA induce overt hepatic hemorrhage. By investigating the chimeric and truncated toxins, we demonstrated that the enzymatic domain of TcsH alone is not sufficient to determine its potent hepatic hemorrhagic toxicity in mice. Likewise, the combined repetitive oligopeptide (CROP) domain of TcsH/TcdA alone also failed to explain their strong hemorrhagic activity in mice. Lastly, we showed that disrupting the first two short repeats of CROPs in TcsH and TcdA impaired hemorrhagic toxicity without causing overt changes in cytotoxicity and lethality. These findings lead to a deeper understanding of toxin-induced hemorrhage and the pathogenesis of LCTs and could be insightful in developing therapeutic avenues against clostridial infections. IMPORTANCE Paeniclostridium sordellii and Clostridioides difficile infections often cause hemorrhage in the affected tissues and organs, which is mainly attributed to their hemorrhagic toxins, TcsH and TcdA. In this study, we demonstrate that TcsH and TcdA, but not other related toxins. including Clostridioides difficile toxin B and TcsL, induce severe hepatic hemorrhage in mice. We further determine that a small region in TcsH and TcdA is critical for the hemorrhagic toxicity but not cytotoxicity or lethality of these toxins. Based on these results, we propose that the hemorrhagic toxicity of TcsH and TcdA is due to an uncharacterized mechanism, such as the presence of an unknown receptor, and future studies to identify the interactive host factors are warranted.
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Affiliation(s)
- Yangling Zheng
- College of Life Sciences, Zhejiang University, Hangzhou, Zhejiang, China
- Center for Infectious Disease Research, Westlake Laboratory of Life Sciences and Biomedicine, Hangzhou, Zhejiang, China
- Research Center for Industries of the Future and Key Laboratory of Multi-omics in Infection and Immunity of Zhejiang Province, School of Medicine, School of Life Sciences, Westlake University, Hangzhou, Zhejiang, China
- Institute of Basic Medical Sciences, Westlake Institute for Advanced Study, Hangzhou, Zhejiang, China
| | - Qi Yang
- College of Life Sciences, Zhejiang University, Hangzhou, Zhejiang, China
- Center for Infectious Disease Research, Westlake Laboratory of Life Sciences and Biomedicine, Hangzhou, Zhejiang, China
- Research Center for Industries of the Future and Key Laboratory of Multi-omics in Infection and Immunity of Zhejiang Province, School of Medicine, School of Life Sciences, Westlake University, Hangzhou, Zhejiang, China
- Institute of Basic Medical Sciences, Westlake Institute for Advanced Study, Hangzhou, Zhejiang, China
| | - Jianhua Luo
- Center for Infectious Disease Research, Westlake Laboratory of Life Sciences and Biomedicine, Hangzhou, Zhejiang, China
- Research Center for Industries of the Future and Key Laboratory of Multi-omics in Infection and Immunity of Zhejiang Province, School of Medicine, School of Life Sciences, Westlake University, Hangzhou, Zhejiang, China
- Institute of Basic Medical Sciences, Westlake Institute for Advanced Study, Hangzhou, Zhejiang, China
| | - Yuanyuan Zhang
- Center for Infectious Disease Research, Westlake Laboratory of Life Sciences and Biomedicine, Hangzhou, Zhejiang, China
- Research Center for Industries of the Future and Key Laboratory of Multi-omics in Infection and Immunity of Zhejiang Province, School of Medicine, School of Life Sciences, Westlake University, Hangzhou, Zhejiang, China
- Institute of Basic Medical Sciences, Westlake Institute for Advanced Study, Hangzhou, Zhejiang, China
| | - Xingxing Li
- Center for Infectious Disease Research, Westlake Laboratory of Life Sciences and Biomedicine, Hangzhou, Zhejiang, China
- Research Center for Industries of the Future and Key Laboratory of Multi-omics in Infection and Immunity of Zhejiang Province, School of Medicine, School of Life Sciences, Westlake University, Hangzhou, Zhejiang, China
- Institute of Basic Medical Sciences, Westlake Institute for Advanced Study, Hangzhou, Zhejiang, China
| | - Liuqing He
- Center for Infectious Disease Research, Westlake Laboratory of Life Sciences and Biomedicine, Hangzhou, Zhejiang, China
- Research Center for Industries of the Future and Key Laboratory of Multi-omics in Infection and Immunity of Zhejiang Province, School of Medicine, School of Life Sciences, Westlake University, Hangzhou, Zhejiang, China
- Institute of Basic Medical Sciences, Westlake Institute for Advanced Study, Hangzhou, Zhejiang, China
| | - Chao Ma
- Center for Infectious Disease Research, Westlake Laboratory of Life Sciences and Biomedicine, Hangzhou, Zhejiang, China
- Research Center for Industries of the Future and Key Laboratory of Multi-omics in Infection and Immunity of Zhejiang Province, School of Medicine, School of Life Sciences, Westlake University, Hangzhou, Zhejiang, China
- Institute of Basic Medical Sciences, Westlake Institute for Advanced Study, Hangzhou, Zhejiang, China
| | - Liang Tao
- College of Life Sciences, Zhejiang University, Hangzhou, Zhejiang, China
- Center for Infectious Disease Research, Westlake Laboratory of Life Sciences and Biomedicine, Hangzhou, Zhejiang, China
- Research Center for Industries of the Future and Key Laboratory of Multi-omics in Infection and Immunity of Zhejiang Province, School of Medicine, School of Life Sciences, Westlake University, Hangzhou, Zhejiang, China
- Institute of Basic Medical Sciences, Westlake Institute for Advanced Study, Hangzhou, Zhejiang, China
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3
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Doyle DA, DeAngelis PL, Ballard JD. CSPG4-dependent cytotoxicity for C. difficile TcdB is influenced by extracellular calcium and chondroitin sulfate. mSphere 2024; 9:e0009424. [PMID: 38470254 PMCID: PMC11036797 DOI: 10.1128/msphere.00094-24] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2024] [Accepted: 02/21/2024] [Indexed: 03/13/2024] Open
Abstract
TcdB is an intracellular bacterial toxin indispensable to Clostridioides difficile infections. The ability to use chondroitin sulfate proteoglycan 4 (CSPG4) as a primary cell surface receptor is evolutionarily conserved by the two major variants of TcdB. As CSPG4 does not typically undergo receptor-mediated endocytosis, we sought to identify environmental factors that stabilize interactions between TcdB and CSPG4 to promote cell binding and entry into the cytosol. Using a series of TcdB receptor-binding mutants and cell lines with various receptor expression profiles, we discovered that extracellular Ca2+ promotes receptor-specific interactions with TcdB. Specifically, TcdB exhibits preferential binding to CSPG4 in the presence of Ca2+, with the absence of Ca2+ resulting in CSPG4-independent cell surface interactions. Furthermore, Ca2+ did not enhance TcdB binding to chondroitin sulfate (CS), the sole glycosaminoglycan of CSPG4. Instead, CS was found to impact the rate of cell entry by TcdB. Collectively, results from this study indicate that Ca2+ enhances cell binding by TcdB and CS interactions contribute to subsequent steps in cell entry. IMPORTANCE Clostridioides difficile is a leading cause of antibiotic-associated gastrointestinal illness, and many disease pathologies are caused by the toxin TcdB. TcdB engages multiple cell surface receptors, with receptor tropisms differing among the variants of the toxin. Chondroitin sulfate proteoglycan 4 (CSPG4) is a critical receptor for multiple forms of TcdB, and insights into TcdB-CSPG4 interactions are applicable to many disease-causing strains of C. difficile. CSPG4 is modified by chondroitin sulfate (CS) and contains laminin-G repeats stabilized by Ca2+, yet the relative contributions of CS and Ca2+ to TcdB cytotoxicity have not been determined. This study demonstrates distinct roles in TcdB cell binding and cell entry for Ca2+ and CS, respectively. These effects are specific to CSPG4 and contribute to the activities of a prominent isoform of TcdB that utilizes this receptor. These findings advance an understanding of factors contributing to TcdB's mechanism of action and contribution to C. difficile disease.
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Affiliation(s)
- D. Annie Doyle
- Department of Microbiology and Immunology, The University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma, USA
| | - Paul L. DeAngelis
- Department of Biochemistry and Physiology, The University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma, USA
| | - Jimmy D. Ballard
- Department of Microbiology and Immunology, The University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma, USA
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Hu C, Garey KW. Microscopy methods for Clostridioides difficile. Anaerobe 2024; 86:102822. [PMID: 38341023 DOI: 10.1016/j.anaerobe.2024.102822] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2023] [Revised: 01/25/2024] [Accepted: 01/29/2024] [Indexed: 02/12/2024]
Abstract
Microscopic technologies including light and fluorescent, transmission electron microscopy (TEM), scanning electron microscopy (SEM), and cryo-electron microscopy have been widely utilized to visualize Clostridioides difficile at the molecular, cellular, community, and structural biology level. This comprehensive review summarizes the microscopy tools (fluorescent and reporter system) in their use to study different aspects of C. difficile life cycle and virulence (sporulation, germination) or applications (detection of C. difficile or use of antimicrobials). With these developing techniques, microscopy tools will be able to find broader applications and address more challenging questions to study C. difficile and C. difficile infection.
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Affiliation(s)
- Chenlin Hu
- University of Houston College of Pharmacy, Houston, TX, USA
| | - Kevin W Garey
- University of Houston College of Pharmacy, Houston, TX, USA.
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Karnchanapandh K, Sanachai K, Poo-Arporn RP, Rungrotmongkol T. Enhancing bezlotoxumab binding to C. difficile toxin B2: insights from computational simulations and mutational analyses for antibody design. J Biomol Struct Dyn 2024:1-11. [PMID: 38511411 DOI: 10.1080/07391102.2024.2329785] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2023] [Accepted: 03/06/2024] [Indexed: 03/22/2024]
Abstract
Clostridioides difficile infection (CDI) is a significant concern caused by widespread antibiotic use, resulting in diarrhea and inflammation from the gram-positive anaerobic bacterium C. difficile. Although bezlotoxumab (Bez), a monoclonal antibody (mAb), was developed to address CDI recurrences, the recurrence rate remains high, partly due to reduced neutralization efficiency against toxin B2. In this study, we aimed to enhance the binding of Bez to C. difficile toxin B2 by combining computational simulations and mutational analyses. We identified specific mutations in Bez, including S28R, S31W/K, Y32R, S56W and G103D/S in the heavy chain (Hc), and S32F/H/R/W/Y in the light chain (Lc), which significantly improved binding to toxin B2 and formed critical protein-protein interactions. Through molecular dynamics simulations, several single mutations, such as HcS28R, LcS32H, LcS32R, LcS32W and LcS32Y, exhibited superior binding affinities to toxin B2 compared to Bez wild-type (WT), primarily attributed to Coulombic interactions. Combining the HcS28R mutation with four different mutations at residue LcS32 led to even greater binding affinities in double mutants (MTs), particularly HcS28R/LcS32H, HcS28R/LcS32R and HcS28R/LcS32Y, reinforcing protein-protein binding. Analysis of per-residue decomposition free energy highlighted key residues contributing significantly to enhanced binding interactions, emphasizing the role of electrostatic interactions. These findings offer insights into rational Bez MT design for improved toxin B2 binding, providing a foundation for developing more effective antibodies to neutralize toxin B2 and combat-related infections.Communicated by Ramaswamy H. Sarma.
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Affiliation(s)
- Kun Karnchanapandh
- Program in Bioinformatics and Computational Biology, Graduate School, Chulalongkorn University, Bangkok, Thailand
| | - Kamonpan Sanachai
- Department of Biochemistry, Faculty of Science, Khon Kaen University, Khon Kaen, Thailand
| | - Rungtiva P Poo-Arporn
- Biological Engineering Program, Faculty of Engineering, King Mongkut's University of Technology Thonburi, Bangkok, Thailand
| | - Thanyada Rungrotmongkol
- Program in Bioinformatics and Computational Biology, Graduate School, Chulalongkorn University, Bangkok, Thailand
- Center of Excellence in Biocatalyst and Sustainable Biotechnology, Department of Biochemistry, Faculty of Science, Chulalongkorn University, Bangkok, Thailand
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6
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Alanis E, Aguilar F, Banaei N, Dean FB, Villarreal A, Alanis M, Lozano K, Bullard JM, Zhang Y. A rationally designed antimicrobial peptide from structural and functional insights of Clostridioides difficile translation initiation factor 1. Microbiol Spectr 2024; 12:e0277323. [PMID: 38329351 PMCID: PMC10913371 DOI: 10.1128/spectrum.02773-23] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2023] [Accepted: 01/12/2024] [Indexed: 02/09/2024] Open
Abstract
A significant increase of hospital-acquired bacterial infections during the COVID-19 pandemic has become an urgent medical problem. Clostridioides difficile is an urgent antibiotic-resistant bacterial pathogen and a leading causative agent of nosocomial infections. The increasing recurrence of C. difficile infection and antibiotic resistance in C. difficile has led to an unmet need for the discovery of new compounds distinctly different from present antimicrobials, while antimicrobial peptides as promising alternatives to conventional antibiotics have attracted growing interest recently. Protein synthesis is an essential metabolic process in all bacteria and a validated antibiotic target. Initiation factor 1 from C. difficile (Cd-IF1) is the smallest of the three initiation factors that acts to establish the 30S initiation complex to initiate translation during protein biosynthesis. Here, we report the solution nuclear magnetic resonance (NMR) structure of Cd-IF1 which adopts a typical β-barrel fold and consists of a five-stranded β-sheet and one short α-helix arranged in the sequential order β1-β2-β3-α1-β4-β5. The interaction of Cd-IF1 with the 30S ribosomal subunit was studied by NMR titration for the construction of a structural model of Cd-IF1 binding with the 30S subunit. The short α-helix in IF1 was found to be critical for IF1 ribosomal binding. A peptide derived from this α-helix was tested and displayed a high ability to inhibit the growth of C. difficile and other bacterial strains. These results provide a clue for the rational design of new antimicrobials.IMPORTANCEBacterial infections continue to represent a major worldwide health hazard due to the emergence of drug-resistant strains. Clostridioides difficile is a common nosocomial pathogen and the causative agent in many infections resulting in an increase in morbidity and mortality. Bacterial protein synthesis is an essential metabolic process and an important target for antibiotic development; however, the precise structural mechanism underlying the process in C. difficile remains unknown. This study reports the solution structure of C. difficile translation initiation factor 1 (IF1) and its interaction with the 30S ribosomal subunit. A short α-helix in IF1 structure was identified as critically important for ribosomal binding and function in regulating the translation initiation, which allowed a rational design of a new peptide. The peptide demonstrated a high ability to inhibit bacterial growth with broad-spectrum antibacterial activity. This study provides a new clue for the rational design of new antimicrobials against bacterial infections.
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Affiliation(s)
- Elvira Alanis
- School of Integrative Biological and Chemical Sciences, The University of Texas Rio Grande Valley, Edinburg, Texas, USA
| | - Faith Aguilar
- School of Integrative Biological and Chemical Sciences, The University of Texas Rio Grande Valley, Edinburg, Texas, USA
| | - Niaz Banaei
- Department of Pathology, Stanford University School of Medicine, Stanford, California, USA
- Department of Medicine, Division of Infectious Diseases and Geographic Medicine, Stanford University School of Medicine, Stanford, California, USA
| | - Frank B. Dean
- School of Integrative Biological and Chemical Sciences, The University of Texas Rio Grande Valley, Edinburg, Texas, USA
| | - Alexa Villarreal
- Department of Mechanical Engineering, The University of Texas Rio Grande Valley, Edinburg, Texas, USA
| | - Miguel Alanis
- School of Integrative Biological and Chemical Sciences, The University of Texas Rio Grande Valley, Edinburg, Texas, USA
| | - Karen Lozano
- Department of Mechanical Engineering, The University of Texas Rio Grande Valley, Edinburg, Texas, USA
| | - James M. Bullard
- School of Integrative Biological and Chemical Sciences, The University of Texas Rio Grande Valley, Edinburg, Texas, USA
| | - Yonghong Zhang
- School of Integrative Biological and Chemical Sciences, The University of Texas Rio Grande Valley, Edinburg, Texas, USA
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Zhou R, He L, Zhang J, Zhang X, Li Y, Zhan X, Tao L. Molecular basis of TMPRSS2 recognition by Paeniclostridium sordellii hemorrhagic toxin. Nat Commun 2024; 15:1976. [PMID: 38438396 PMCID: PMC10912200 DOI: 10.1038/s41467-024-46394-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2023] [Accepted: 02/26/2024] [Indexed: 03/06/2024] Open
Abstract
Hemorrhagic toxin (TcsH) is a major virulence factor produced by Paeniclostridium sordellii, which is a non-negligible threat to women undergoing childbirth or abortions. Recently, Transmembrane Serine Protease 2 (TMPRSS2) was identified as a host receptor of TcsH. Here, we show the cryo-EM structures of the TcsH-TMPRSS2 complex and uncover that TcsH binds to the serine protease domain (SPD) of TMPRSS2 through the CROP unit-VI. This receptor binding mode is unique among LCTs. Five top surface loops of TMPRSS2SPD, which also determine the protease substrate specificity, constitute the structural determinants recognized by TcsH. The binding of TcsH inhibits the proteolytic activity of TMPRSS2, whereas its implication in disease manifestations remains unclear. We further show that mutations selectively disrupting TMPRSS2-binding reduce TcsH toxicity in the intestinal epithelium of the female mice. These findings together shed light on the distinct molecular basis of TcsH-TMPRSS2 interactions, which expands our knowledge of host recognition mechanisms employed by LCTs and provides novel targets for developing therapeutics against P. sordellii infections.
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Affiliation(s)
- Ruoyu Zhou
- College of Life Sciences, Fudan University, Shanghai, 200433, China
- Center for Infectious Disease Research, Westlake Laboratory of Life Sciences and Biomedicine, Hangzhou, 310024, China
- Key Laboratory of Structural Biology of Zhejiang Province, School of Life Sciences, Westlake University, Hangzhou, 310024, China
- Westlake Institute for Advanced Study, Hangzhou, 310024, China
| | - Liuqing He
- Center for Infectious Disease Research, Westlake Laboratory of Life Sciences and Biomedicine, Hangzhou, 310024, China
- Key Laboratory of Structural Biology of Zhejiang Province, School of Life Sciences, Westlake University, Hangzhou, 310024, China
- Westlake Institute for Advanced Study, Hangzhou, 310024, China
- Research Center for Industries of the Future, Westlake University, Hangzhou, 310024, China
| | - Jiahao Zhang
- Center for Infectious Disease Research, Westlake Laboratory of Life Sciences and Biomedicine, Hangzhou, 310024, China
- Key Laboratory of Structural Biology of Zhejiang Province, School of Life Sciences, Westlake University, Hangzhou, 310024, China
- Westlake Institute for Advanced Study, Hangzhou, 310024, China
| | - Xiaofeng Zhang
- Center for Infectious Disease Research, Westlake Laboratory of Life Sciences and Biomedicine, Hangzhou, 310024, China
- Key Laboratory of Structural Biology of Zhejiang Province, School of Life Sciences, Westlake University, Hangzhou, 310024, China
- Westlake Institute for Advanced Study, Hangzhou, 310024, China
| | - Yanyan Li
- Center for Infectious Disease Research, Westlake Laboratory of Life Sciences and Biomedicine, Hangzhou, 310024, China
- Key Laboratory of Structural Biology of Zhejiang Province, School of Life Sciences, Westlake University, Hangzhou, 310024, China
- Westlake Institute for Advanced Study, Hangzhou, 310024, China
| | - Xiechao Zhan
- Center for Infectious Disease Research, Westlake Laboratory of Life Sciences and Biomedicine, Hangzhou, 310024, China.
- Key Laboratory of Structural Biology of Zhejiang Province, School of Life Sciences, Westlake University, Hangzhou, 310024, China.
- Westlake Institute for Advanced Study, Hangzhou, 310024, China.
| | - Liang Tao
- College of Life Sciences, Fudan University, Shanghai, 200433, China.
- Center for Infectious Disease Research, Westlake Laboratory of Life Sciences and Biomedicine, Hangzhou, 310024, China.
- Key Laboratory of Structural Biology of Zhejiang Province, School of Life Sciences, Westlake University, Hangzhou, 310024, China.
- Westlake Institute for Advanced Study, Hangzhou, 310024, China.
- Research Center for Industries of the Future, Westlake University, Hangzhou, 310024, China.
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Kinsolving J, Bous J, Kozielewicz P, Košenina S, Shekhani R, Grätz L, Masuyer G, Wang Y, Stenmark P, Dong M, Schulte G. Structural and functional insight into the interaction of Clostridioides difficile toxin B and FZD 7. Cell Rep 2024; 43:113727. [PMID: 38308843 DOI: 10.1016/j.celrep.2024.113727] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2023] [Revised: 01/12/2024] [Accepted: 01/15/2024] [Indexed: 02/05/2024] Open
Abstract
The G protein-coupled receptors of the Frizzled (FZD) family, in particular FZD1,2,7, are receptors that are exploited by Clostridioides difficile toxin B (TcdB), the major virulence factor responsible for pathogenesis associated with Clostridioides difficile infection. We employ a live-cell assay examining the affinity between full-length FZDs and TcdB. Moreover, we present cryoelectron microscopy structures of TcdB alone and in complex with full-length FZD7, which reveal that large structural rearrangements of the combined repetitive polypeptide domain are required for interaction with FZDs and other TcdB receptors, constituting a first step for receptor recognition. Furthermore, we show that bezlotoxumab, an FDA-approved monoclonal antibody to treat Clostridioides difficile infection, favors the apo-TcdB structure and thus disrupts binding with FZD7. The dynamic transition between the two conformations of TcdB also governs the stability of the pore-forming region. Thus, our work provides structural and functional insight into how conformational dynamics of TcdB determine receptor binding.
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Affiliation(s)
- Julia Kinsolving
- Karolinska Institutet, Department Physiology & Pharmacology, Sec. Receptor Biology & Signaling, Biomedicum, 17165 Stockholm, Sweden
| | - Julien Bous
- Karolinska Institutet, Department Physiology & Pharmacology, Sec. Receptor Biology & Signaling, Biomedicum, 17165 Stockholm, Sweden
| | - Pawel Kozielewicz
- Karolinska Institutet, Department Physiology & Pharmacology, Sec. Receptor Biology & Signaling, Biomedicum, 17165 Stockholm, Sweden
| | - Sara Košenina
- Department of Biochemistry and Biophysics, Stockholm University, Stockholm, Sweden
| | - Rawan Shekhani
- Karolinska Institutet, Department Physiology & Pharmacology, Sec. Receptor Biology & Signaling, Biomedicum, 17165 Stockholm, Sweden
| | - Lukas Grätz
- Karolinska Institutet, Department Physiology & Pharmacology, Sec. Receptor Biology & Signaling, Biomedicum, 17165 Stockholm, Sweden
| | - Geoffrey Masuyer
- Department of Biochemistry and Biophysics, Stockholm University, Stockholm, Sweden
| | - Yuankai Wang
- Department of Urology, Boston Children's Hospital, Department of Surgery and Department of Microbiology, Harvard Medical School, Boston, MA, USA
| | - Pål Stenmark
- Department of Biochemistry and Biophysics, Stockholm University, Stockholm, Sweden
| | - Min Dong
- Department of Urology, Boston Children's Hospital, Department of Surgery and Department of Microbiology, Harvard Medical School, Boston, MA, USA
| | - Gunnar Schulte
- Karolinska Institutet, Department Physiology & Pharmacology, Sec. Receptor Biology & Signaling, Biomedicum, 17165 Stockholm, Sweden.
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Karnchanapandh K, Hanpaibool C, Sanachai K, Rungrotmongkol T. Elucidation of bezlotoxumab binding specificity to toxin B in Clostridioides difficile. J Biomol Struct Dyn 2024; 42:1617-1628. [PMID: 37098802 DOI: 10.1080/07391102.2023.2201360] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/26/2022] [Accepted: 04/05/2023] [Indexed: 04/27/2023]
Abstract
C. difficile or Clostridioides difficile infection (CDI) is currently one of the major causes of epidemics worldwide. Toxin B from Clostridioides difficile toxin B (TcdB) infection is the main target protein inhibiting CDI recurrence. Clinical research suggested that bezlotoxumab's (Bez) efficiency is significantly reduced in neutralizing the B2 strain compared to the B1 strain. The monoclonal antibody (mAb) functions by binding to the epitope 1 and 2 regions in the combined repetitive oligopeptide (CROP) domain. Some binding residues are distinctively different between B1 and B2 strains. In this work, we aimed to elucidate and compare insights into the interaction of toxins B1 and B2 in complex with Bez by using all-atom molecular dynamics (MD) simulations and binding free energy calculations. The predicted ΔGbinding values suggested that the antibody (Ab) could bind to toxin B1 significantly better than B2, supported by higher salt bridge and hydrogen bonding (H-bonding) interactions, as well as the number of contact residues between the two focused proteins. The toxin B1 residues important for binding with Bez were E1878, T1901, E1902, F1905, N1941, V1946, N2031, T2032, E2033, V2076, V2077, and E2092. The lower susceptibility of Bez towards toxin B2 was primarily due to a change of residue E2033 from glutamate to alanine (A2033) and the loss of E1878 and E1902 contributions, as determined by the intermolecular interaction changes from the dynamic residue interaction network (dRIN) analysis. The obtained data strengthen our understanding of Bez/toxin B binding.
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Affiliation(s)
- Kun Karnchanapandh
- Program in Bioinformatics and Computational Biology, Graduate School, Chulalongkorn University, Bangkok, Thailand
| | - Chonnikan Hanpaibool
- Center of Excellence in Biocatalyst and Sustainable Biotechnology, Department of Biochemistry, Faculty of Science, Chulalongkorn University, Bangkok, Thailand
| | - Kamonpan Sanachai
- Department of Biochemistry, Faculty of Science, Khon Kaen University, Khon Kaen, Thailand
| | - Thanyada Rungrotmongkol
- Program in Bioinformatics and Computational Biology, Graduate School, Chulalongkorn University, Bangkok, Thailand
- Center of Excellence in Biocatalyst and Sustainable Biotechnology, Department of Biochemistry, Faculty of Science, Chulalongkorn University, Bangkok, Thailand
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10
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Papatheodorou P, Minton NP, Aktories K, Barth H. An Updated View on the Cellular Uptake and Mode-of-Action of Clostridioides difficile Toxins. Adv Exp Med Biol 2024; 1435:219-247. [PMID: 38175478 DOI: 10.1007/978-3-031-42108-2_11] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/05/2024]
Abstract
Research on the human gut pathogen Clostridioides (C.) difficile and its toxins continues to attract much attention as a consequence of the threat to human health posed by hypervirulent strains. Toxin A (TcdA) and Toxin B (TcdB) are the two major virulence determinants of C. difficile. Both are single-chain proteins with a similar multidomain architecture. Certain hypervirulent C. difficile strains also produce a third toxin, namely binary toxin CDT (C. difficile transferase). C. difficile toxins are the causative agents of C. difficile-associated diseases (CDADs), such as antibiotics-associated diarrhea and pseudomembranous colitis. For that reason, considerable efforts have been expended to unravel their molecular mode-of-action and the cellular mechanisms responsible for their uptake. Many of these studies have been conducted in European laboratories. Here, we provide an update on our previous review (Papatheodorou et al. Adv Exp Med Biol, 2018) on important advances in C. difficile toxins research.
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Affiliation(s)
- Panagiotis Papatheodorou
- Institute of Experimental and Clinical Pharmacology, Toxicology and Pharmacology of Natural Products, Ulm University Medical Center, Ulm, Germany.
| | - Nigel P Minton
- BBSRC/EPSRC Synthetic Biology Research Centre, University of Nottingham, Nottingham, UK
| | - Klaus Aktories
- Institute of Experimental and Clinical Pharmacology and Toxicology, University of Freiburg, Freiburg, Germany
| | - Holger Barth
- Institute of Experimental and Clinical Pharmacology, Toxicology and Pharmacology of Natural Products, Ulm University Medical Center, Ulm, Germany
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11
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Bratkovič T, Zahirović A, Bizjak M, Rupnik M, Štrukelj B, Berlec A. New treatment approaches for Clostridioides difficile infections: alternatives to antibiotics and fecal microbiota transplantation. Gut Microbes 2024; 16:2337312. [PMID: 38591915 PMCID: PMC11005816 DOI: 10.1080/19490976.2024.2337312] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/29/2024] [Accepted: 03/27/2024] [Indexed: 04/10/2024] Open
Abstract
Clostridioides difficile causes a range of debilitating intestinal symptoms that may be fatal. It is particularly problematic as a hospital-acquired infection, causing significant costs to the health care system. Antibiotics, such as vancomycin and fidaxomicin, are still the drugs of choice for C. difficile infections, but their effectiveness is limited, and microbial interventions are emerging as a new treatment option. This paper focuses on alternative treatment approaches, which are currently in various stages of development and can be divided into four therapeutic strategies. Direct killing of C. difficile (i) includes beside established antibiotics, less studied bacteriophages, and their derivatives, such as endolysins and tailocins. Restoration of microbiota composition and function (ii) is achieved with fecal microbiota transplantation, which has recently been approved, with standardized defined microbial mixtures, and with probiotics, which have been administered with moderate success. Prevention of deleterious effects of antibiotics on microbiota is achieved with agents for the neutralization of antibiotics that act in the gut and are nearing regulatory approval. Neutralization of C. difficile toxins (iii) which are crucial virulence factors is achieved with antibodies/antibody fragments or alternative binding proteins. Of these, the monoclonal antibody bezlotoxumab is already in clinical use. Immunomodulation (iv) can help eliminate or prevent C. difficile infection by interfering with cytokine signaling. Small-molecule agents without bacteriolytic activity are usually selected by drug repurposing and can act via a variety of mechanisms. The multiple treatment options described in this article provide optimism for the future treatment of C. difficile infection.
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Affiliation(s)
- Tomaž Bratkovič
- Faculty of Pharmacy, University of Ljubljana, Ljubljana, Slovenia
| | - Abida Zahirović
- Department of Biotechnology, Jožef Stefan Institute, Ljubljana, Slovenia
| | - Maruša Bizjak
- Department of Biotechnology, Jožef Stefan Institute, Ljubljana, Slovenia
| | - Maja Rupnik
- National Laboratory for Health, Environment and Food, Prvomajska 1, Maribor, Slovenia
- Faculty of Medicine, University of Maribor, Maribor, Slovenia
| | - Borut Štrukelj
- Faculty of Pharmacy, University of Ljubljana, Ljubljana, Slovenia
- Department of Biotechnology, Jožef Stefan Institute, Ljubljana, Slovenia
| | - Aleš Berlec
- Faculty of Pharmacy, University of Ljubljana, Ljubljana, Slovenia
- Department of Biotechnology, Jožef Stefan Institute, Ljubljana, Slovenia
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12
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Zhou Y, Zhan X, Luo J, Li D, Zhou R, Zhang J, Pan Z, Zhang Y, Jia T, Zhang X, Li Y, Tao L. Structural dynamics of the CROPs domain control stability and toxicity of Paeniclostridium sordellii lethal toxin. Nat Commun 2023; 14:8426. [PMID: 38114525 PMCID: PMC10730571 DOI: 10.1038/s41467-023-44169-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2023] [Accepted: 12/04/2023] [Indexed: 12/21/2023] Open
Abstract
Paeniclostridium sordellii lethal toxin (TcsL) is a potent exotoxin that causes lethal toxic shock syndrome associated with fulminant bacterial infections. TcsL belongs to the large clostridial toxin (LCT) family. Here, we report that TcsL with varied lengths of combined repetitive oligopeptides (CROPs) deleted show increased autoproteolysis as well as higher cytotoxicity. We next present cryo-EM structures of full-length TcsL, at neutral (pH 7.4) and acidic (pH 5.0) conditions. The TcsL at neutral pH exhibits in the open conformation, which resembles reported TcdB structures. Low pH induces the conformational change of partial TcsL to the closed form. Two intracellular interfaces are observed in the closed conformation, which possibly locks the cysteine protease domain and hinders the binding of the host receptor. Our findings provide insights into the structure and function of TcsL and reveal mechanisms for CROPs-mediated modulation of autoproteolysis and cytotoxicity, which could be common across the LCT family.
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Affiliation(s)
- Yao Zhou
- Center for Infectious Disease Research, Westlake Laboratory of Life Sciences and Biomedicine, Hangzhou, Zhejiang, 310024, China
- Key Laboratory of Structural Biology of Zhejiang Province, School of Life Sciences, Westlake University, Hangzhou, Zhejiang, 310024, China
- Westlake Institute for Advanced Study, Hangzhou, Zhejiang, 310024, China
- Research Center for Industries of the Future, Westlake University, Hangzhou, Zhejiang, 310024, China
| | - Xiechao Zhan
- Center for Infectious Disease Research, Westlake Laboratory of Life Sciences and Biomedicine, Hangzhou, Zhejiang, 310024, China.
- Key Laboratory of Structural Biology of Zhejiang Province, School of Life Sciences, Westlake University, Hangzhou, Zhejiang, 310024, China.
- Westlake Institute for Advanced Study, Hangzhou, Zhejiang, 310024, China.
| | - Jianhua Luo
- Center for Infectious Disease Research, Westlake Laboratory of Life Sciences and Biomedicine, Hangzhou, Zhejiang, 310024, China
- Key Laboratory of Structural Biology of Zhejiang Province, School of Life Sciences, Westlake University, Hangzhou, Zhejiang, 310024, China
- Westlake Institute for Advanced Study, Hangzhou, Zhejiang, 310024, China
- Research Center for Industries of the Future, Westlake University, Hangzhou, Zhejiang, 310024, China
| | - Diyin Li
- Center for Infectious Disease Research, Westlake Laboratory of Life Sciences and Biomedicine, Hangzhou, Zhejiang, 310024, China
- Key Laboratory of Structural Biology of Zhejiang Province, School of Life Sciences, Westlake University, Hangzhou, Zhejiang, 310024, China
- Westlake Institute for Advanced Study, Hangzhou, Zhejiang, 310024, China
- Research Center for Industries of the Future, Westlake University, Hangzhou, Zhejiang, 310024, China
| | - Ruoyu Zhou
- Center for Infectious Disease Research, Westlake Laboratory of Life Sciences and Biomedicine, Hangzhou, Zhejiang, 310024, China
- Key Laboratory of Structural Biology of Zhejiang Province, School of Life Sciences, Westlake University, Hangzhou, Zhejiang, 310024, China
- Westlake Institute for Advanced Study, Hangzhou, Zhejiang, 310024, China
| | - Jiahao Zhang
- Center for Infectious Disease Research, Westlake Laboratory of Life Sciences and Biomedicine, Hangzhou, Zhejiang, 310024, China
- Key Laboratory of Structural Biology of Zhejiang Province, School of Life Sciences, Westlake University, Hangzhou, Zhejiang, 310024, China
- Westlake Institute for Advanced Study, Hangzhou, Zhejiang, 310024, China
| | - Zhenrui Pan
- Center for Infectious Disease Research, Westlake Laboratory of Life Sciences and Biomedicine, Hangzhou, Zhejiang, 310024, China
- Key Laboratory of Structural Biology of Zhejiang Province, School of Life Sciences, Westlake University, Hangzhou, Zhejiang, 310024, China
- Westlake Institute for Advanced Study, Hangzhou, Zhejiang, 310024, China
| | - Yuanyuan Zhang
- Center for Infectious Disease Research, Westlake Laboratory of Life Sciences and Biomedicine, Hangzhou, Zhejiang, 310024, China
- Key Laboratory of Structural Biology of Zhejiang Province, School of Life Sciences, Westlake University, Hangzhou, Zhejiang, 310024, China
- Westlake Institute for Advanced Study, Hangzhou, Zhejiang, 310024, China
| | - Tianhui Jia
- Center for Infectious Disease Research, Westlake Laboratory of Life Sciences and Biomedicine, Hangzhou, Zhejiang, 310024, China
- Key Laboratory of Structural Biology of Zhejiang Province, School of Life Sciences, Westlake University, Hangzhou, Zhejiang, 310024, China
- Westlake Institute for Advanced Study, Hangzhou, Zhejiang, 310024, China
- Research Center for Industries of the Future, Westlake University, Hangzhou, Zhejiang, 310024, China
| | - Xiaofeng Zhang
- Center for Infectious Disease Research, Westlake Laboratory of Life Sciences and Biomedicine, Hangzhou, Zhejiang, 310024, China
- Key Laboratory of Structural Biology of Zhejiang Province, School of Life Sciences, Westlake University, Hangzhou, Zhejiang, 310024, China
- Westlake Institute for Advanced Study, Hangzhou, Zhejiang, 310024, China
| | - Yanyan Li
- Center for Infectious Disease Research, Westlake Laboratory of Life Sciences and Biomedicine, Hangzhou, Zhejiang, 310024, China
- Key Laboratory of Structural Biology of Zhejiang Province, School of Life Sciences, Westlake University, Hangzhou, Zhejiang, 310024, China
- Westlake Institute for Advanced Study, Hangzhou, Zhejiang, 310024, China
| | - Liang Tao
- Center for Infectious Disease Research, Westlake Laboratory of Life Sciences and Biomedicine, Hangzhou, Zhejiang, 310024, China.
- Key Laboratory of Structural Biology of Zhejiang Province, School of Life Sciences, Westlake University, Hangzhou, Zhejiang, 310024, China.
- Westlake Institute for Advanced Study, Hangzhou, Zhejiang, 310024, China.
- Research Center for Industries of the Future, Westlake University, Hangzhou, Zhejiang, 310024, China.
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13
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Abstract
Clostridioides difficile is the most common cause of nosocomial antibiotic-associated diarrhea, and is responsible for a spectrum of diseases characterized by high levels of recurrence, morbidity, and mortality. Treatment is complex, since antibiotics constitute both the main treatment and the major risk factor for infection. Worryingly, resistance to multiple antibiotics is becoming increasingly widespread, leading to the classification of this pathogen as an urgent threat to global health. As a consummate opportunist, C. difficile is well equipped for promoting disease, owing to its arsenal of virulence factors: transmission of this anaerobe is highly efficient due to the formation of robust endospores, and an array of adhesins promote gut colonization. C. difficile produces multiple toxins acting upon gut epithelia, resulting in manifestations typical of diarrheal disease, and severe inflammation in a subset of patients. This review focuses on such virulence factors, as well as the importance of antimicrobial resistance and genome plasticity in enabling pathogenesis and persistence of this important pathogen.
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Affiliation(s)
- Jessica E Buddle
- Molecular Microbiology, School of Biosciences, University of Sheffield, Sheffield, UK
| | - Robert P Fagan
- Molecular Microbiology, School of Biosciences, University of Sheffield, Sheffield, UK
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14
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He A, Tian S, Kopper O, Horan DJ, Chen P, Bronson RT, Sheng R, Wu H, Sui L, Zhou K, Tao L, Wu Q, Huang Y, Shen Z, Han S, Chen X, Chen H, He X, Robling AG, Jin R, Clevers H, Xiang D, Li Z, Dong M. Targeted inhibition of Wnt signaling with a Clostridioides difficile toxin B fragment suppresses breast cancer tumor growth. PLoS Biol 2023; 21:e3002353. [PMID: 37943878 PMCID: PMC10635564 DOI: 10.1371/journal.pbio.3002353] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2022] [Accepted: 09/27/2023] [Indexed: 11/12/2023] Open
Abstract
Wnt signaling pathways are transmitted via 10 homologous frizzled receptors (FZD1-10) in humans. Reagents broadly inhibiting Wnt signaling pathways reduce growth and metastasis of many tumors, but their therapeutic development has been hampered by the side effect. Inhibitors targeting specific Wnt-FZD pair(s) enriched in cancer cells may reduce side effect, but the therapeutic effect of narrow-spectrum Wnt-FZD inhibitors remains to be established in vivo. Here, we developed a fragment of C. difficile toxin B (TcdBFBD), which recognizes and inhibits a subclass of FZDs, FZD1/2/7, and examined whether targeting this FZD subgroup may offer therapeutic benefits for treating breast cancer models in mice. Utilizing 2 basal-like and 1 luminal-like breast cancer models, we found that TcdBFBD reduces tumor-initiating cells and attenuates growth of basal-like mammary tumor organoids and xenografted tumors, without damaging Wnt-sensitive tissues such as bones in vivo. Furthermore, FZD1/2/7-positive cells are enriched in chemotherapy-resistant cells in both basal-like and luminal mammary tumors treated with cisplatin, and TcdBFBD synergizes strongly with cisplatin in inhibiting both tumor types. These data demonstrate the therapeutic value of narrow-spectrum Wnt signaling inhibitor in treating breast cancers.
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Affiliation(s)
- Aina He
- Department of Oncology, Shanghai Jiaotong University Affiliated Sixth People’s Hospital, Shanghai, People’s Republic of China
- Department of Urology, Boston Children’s Hospital, Harvard Medical School, Boston, Massachusetts, United States of America
- Department of Microbiology and Department of Surgery, Harvard Medical School, Boston, Massachusetts, United States of America
| | - Songhai Tian
- Department of Urology, Boston Children’s Hospital, Harvard Medical School, Boston, Massachusetts, United States of America
- Department of Microbiology and Department of Surgery, Harvard Medical School, Boston, Massachusetts, United States of America
- State Key Laboratory of Natural and Biomimetic Drugs, Department of Molecular and Cellular Pharmacology, School of Pharmaceutical Sciences, Peking University, Beijing, People’s Republic of China
| | - Oded Kopper
- Hubrecht Institute, Royal Netherlands Academy of Arts and Sciences and University Medical Center Utrecht, Utrecht, the Netherlands
| | - Daniel J. Horan
- Department of Anatomy & Cell Biology, Indiana University School of Medicine, Barnhill, Indianapolis, United States of America
| | - Peng Chen
- Department of Physiology and Biophysics, University of California, Irvine, California, United States of America
| | - Roderick T. Bronson
- Rodent Histopathology, Harvard Medical School, Boston, Massachusetts, United States of America
| | - Ren Sheng
- Kirby Neurobiology Center, Boston Children’s Hospital, Department of Neurology, Harvard Medical School, Boston, Massachusetts, United States of America
| | - Hao Wu
- Department of Vascular Biology, Boston Children’s Hospital, Boston, Massachusetts, United States of America
| | - Lufei Sui
- Department of Vascular Biology, Boston Children’s Hospital, Boston, Massachusetts, United States of America
| | - Kun Zhou
- Department of Vascular Biology, Boston Children’s Hospital, Boston, Massachusetts, United States of America
| | - Liang Tao
- Department of Urology, Boston Children’s Hospital, Harvard Medical School, Boston, Massachusetts, United States of America
- Department of Microbiology and Department of Surgery, Harvard Medical School, Boston, Massachusetts, United States of America
| | - Quan Wu
- Department of Urology, Boston Children’s Hospital, Harvard Medical School, Boston, Massachusetts, United States of America
- Department of Microbiology and Department of Surgery, Harvard Medical School, Boston, Massachusetts, United States of America
- Central Laboratory of Medical Research Centre, The First Affiliated Hospital of USTC, Division of Life Sciences and Medicine, University of Science and Technology of China, Hefei, Anhui, People’s Republic of China
| | - Yujing Huang
- Department of Oncology, Shanghai Jiaotong University Affiliated Sixth People’s Hospital, Shanghai, People’s Republic of China
| | - Zan Shen
- Department of Oncology, Shanghai Jiaotong University Affiliated Sixth People’s Hospital, Shanghai, People’s Republic of China
| | - Sen Han
- Division of Genetics, Department of Medicine, Brigham and Women’s Hospital, Boston, Massachusetts, United States of America
- Department of Medicine, Harvard Medical School, Boston, Massachusetts, United States of America
| | - Xueqing Chen
- Division of Genetics, Department of Medicine, Brigham and Women’s Hospital, Boston, Massachusetts, United States of America
- Department of Medicine, Harvard Medical School, Boston, Massachusetts, United States of America
| | - Hong Chen
- Department of Vascular Biology, Boston Children’s Hospital, Boston, Massachusetts, United States of America
| | - Xi He
- Kirby Neurobiology Center, Boston Children’s Hospital, Department of Neurology, Harvard Medical School, Boston, Massachusetts, United States of America
| | - Alexander G. Robling
- Department of Anatomy & Cell Biology, Indiana University School of Medicine, Barnhill, Indianapolis, United States of America
| | - Rongsheng Jin
- Department of Physiology and Biophysics, University of California, Irvine, California, United States of America
| | - Hans Clevers
- Hubrecht Institute, Royal Netherlands Academy of Arts and Sciences and University Medical Center Utrecht, Utrecht, the Netherlands
| | - Dongxi Xiang
- Division of Genetics, Department of Medicine, Brigham and Women’s Hospital, Boston, Massachusetts, United States of America
- Department of Medicine, Harvard Medical School, Boston, Massachusetts, United States of America
- State Key Laboratory of Oncogenes and Related Genes, Shanghai Cancer Institute, Renji Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, People’s Republic of China
- Department of Biliary-Pancreatic Surgery, Renji Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, People’s Republic of China
| | - Zhe Li
- Division of Genetics, Department of Medicine, Brigham and Women’s Hospital, Boston, Massachusetts, United States of America
- Department of Medicine, Harvard Medical School, Boston, Massachusetts, United States of America
| | - Min Dong
- Department of Urology, Boston Children’s Hospital, Harvard Medical School, Boston, Massachusetts, United States of America
- Department of Microbiology and Department of Surgery, Harvard Medical School, Boston, Massachusetts, United States of America
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15
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Childress KO, Cencer CS, Tyska MJ, Lacy DB. Nectin-3 and shed forms of CSPG4 can serve as epithelial cell receptors for Clostridioides difficile TcdB. mBio 2023; 14:e0185723. [PMID: 37747247 PMCID: PMC10653914 DOI: 10.1128/mbio.01857-23] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2023] [Accepted: 07/26/2023] [Indexed: 09/26/2023] Open
Abstract
IMPORTANCE Toxin B (TcdB) is a major virulence factor of Clostridioides difficile, a Gram-positive pathogen that is a leading cause of hospital-acquired diarrhea. While previous studies have established that TcdB can engage multiple cell surface receptors in vitro, little is known about how these interactions promote disease and where these receptors localize on colonic tissue. Here, we used immunofluorescence microscopy to visualize Nectin-3 and CSPG4 on tissue, revealing unexpected localization of both receptors on colonic epithelial cells. We show that Nectin-3, which was previously characterized as an adherens junction protein, is also localized to the brush border of colonocytes. Staining for CSPG4 revealed that it is present along epithelial cell junctions, suggesting that it is shed by fibroblasts along the crypt-surface axis. Collectively, our study provides new insights into how TcdB can gain access to the receptors Nectin-3 and CSPG4 to intoxicate colonic epithelial cells.
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Affiliation(s)
- Kevin O. Childress
- Department of Pathology, Microbiology, and Immunology, Vanderbilt University School of Medicine, Nashville, Tennessee, USA
| | - Caroline S. Cencer
- Department of Cell and Development Biology, Vanderbilt University School of Medicine, Nashville, Tennessee, USA
| | - Matthew J. Tyska
- Department of Cell and Development Biology, Vanderbilt University School of Medicine, Nashville, Tennessee, USA
| | - D. Borden Lacy
- Department of Pathology, Microbiology, and Immunology, Vanderbilt University School of Medicine, Nashville, Tennessee, USA
- Veterans Affairs Tennessee Valley Healthcare System, Nashville, Tennessee, USA
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16
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Manion J, Musser MA, Kuziel GA, Liu M, Shepherd A, Wang S, Lee PG, Zhao L, Zhang J, Marreddy RKR, Goldsmith JD, Yuan K, Hurdle JG, Gerhard R, Jin R, Rakoff-Nahoum S, Rao M, Dong M. C. difficile intoxicates neurons and pericytes to drive neurogenic inflammation. Nature 2023; 622:611-618. [PMID: 37699522 DOI: 10.1038/s41586-023-06607-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2022] [Accepted: 09/05/2023] [Indexed: 09/14/2023]
Abstract
Clostridioides difficile infection (CDI) is a major cause of healthcare-associated gastrointestinal infections1,2. The exaggerated colonic inflammation caused by C. difficile toxins such as toxin B (TcdB) damages tissues and promotes C. difficile colonization3-6, but how TcdB causes inflammation is unclear. Here we report that TcdB induces neurogenic inflammation by targeting gut-innervating afferent neurons and pericytes through receptors, including the Frizzled receptors (FZD1, FZD2 and FZD7) in neurons and chondroitin sulfate proteoglycan 4 (CSPG4) in pericytes. TcdB stimulates the secretion of the neuropeptides substance P (SP) and calcitonin gene-related peptide (CGRP) from neurons and pro-inflammatory cytokines from pericytes. Targeted delivery of the TcdB enzymatic domain, through fusion with a detoxified diphtheria toxin, into peptidergic sensory neurons that express exogeneous diphtheria toxin receptor (an approach we term toxogenetics) is sufficient to induce neurogenic inflammation and recapitulates major colonic histopathology associated with CDI. Conversely, mice lacking SP, CGRP or the SP receptor (neurokinin 1 receptor) show reduced pathology in both models of caecal TcdB injection and CDI. Blocking SP or CGRP signalling reduces tissue damage and C. difficile burden in mice infected with a standard C. difficile strain or with hypervirulent strains expressing the TcdB2 variant. Thus, targeting neurogenic inflammation provides a host-oriented therapeutic approach for treating CDI.
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Affiliation(s)
- John Manion
- Department of Urology, Boston Children's Hospital, Boston, MA, USA
- Department of Surgery, Harvard Medical School, Boston, MA, USA
- Department of Microbiology, Harvard Medical School, Boston, MA, USA
| | - Melissa A Musser
- Division of Gastroenterology, Department of Pediatrics, Boston Children's Hospital and Harvard Medical School, Boston, MA, USA
| | - Gavin A Kuziel
- Department of Microbiology, Harvard Medical School, Boston, MA, USA
- Division of Infectious Diseases, Department of Pediatrics, Boston Children's Hospital and Harvard Medical School, Boston, MA, USA
| | - Min Liu
- Department of Urology, Boston Children's Hospital, Boston, MA, USA
- Department of Surgery, Harvard Medical School, Boston, MA, USA
- Department of Microbiology, Harvard Medical School, Boston, MA, USA
| | - Amy Shepherd
- Division of Gastroenterology, Department of Pediatrics, Boston Children's Hospital and Harvard Medical School, Boston, MA, USA
| | - Siyu Wang
- Department of Urology, Boston Children's Hospital, Boston, MA, USA
- Department of Surgery, Harvard Medical School, Boston, MA, USA
- Department of Microbiology, Harvard Medical School, Boston, MA, USA
- Department of Colorectal Surgery, The First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, China
| | - Pyung-Gang Lee
- Department of Urology, Boston Children's Hospital, Boston, MA, USA
- Department of Surgery, Harvard Medical School, Boston, MA, USA
- Department of Microbiology, Harvard Medical School, Boston, MA, USA
| | - Leo Zhao
- Department of Urology, Boston Children's Hospital, Boston, MA, USA
- Department of Surgery, Harvard Medical School, Boston, MA, USA
- Department of Microbiology, Harvard Medical School, Boston, MA, USA
| | - Jie Zhang
- Department of Urology, Boston Children's Hospital, Boston, MA, USA
- Department of Surgery, Harvard Medical School, Boston, MA, USA
- Department of Microbiology, Harvard Medical School, Boston, MA, USA
| | - Ravi K R Marreddy
- Center for Infectious and Inflammatory Diseases, Institute of Biosciences and Technology, Texas A&M Health Science Center, Houston, TX, USA
| | | | - Ke Yuan
- Division of Pulmonary Medicine, Department of Pediatrics, Boston Children's Hospital and Harvard Medical School, Boston, MA, USA
| | - Julian G Hurdle
- Center for Infectious and Inflammatory Diseases, Institute of Biosciences and Technology, Texas A&M Health Science Center, Houston, TX, USA
| | - Ralf Gerhard
- Institute of Toxicology, Hannover Medical School, Hannover, Germany
| | - Rongsheng Jin
- Department of Physiology and Biophysics, School of Medicine, University of California Irvine, Irvine, CA, USA
| | - Seth Rakoff-Nahoum
- Department of Microbiology, Harvard Medical School, Boston, MA, USA
- Division of Gastroenterology, Department of Pediatrics, Boston Children's Hospital and Harvard Medical School, Boston, MA, USA
- Division of Infectious Diseases, Department of Pediatrics, Boston Children's Hospital and Harvard Medical School, Boston, MA, USA
| | - Meenakshi Rao
- Division of Gastroenterology, Department of Pediatrics, Boston Children's Hospital and Harvard Medical School, Boston, MA, USA.
| | - Min Dong
- Department of Urology, Boston Children's Hospital, Boston, MA, USA.
- Department of Surgery, Harvard Medical School, Boston, MA, USA.
- Department of Microbiology, Harvard Medical School, Boston, MA, USA.
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17
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Kordus SL, Kroh HK, Rodríguez RC, Shrem RA, Peritore-Galve FC, Shupe JA, Wadzinski BE, Lacy DB, Spiller BW. Nanobodies against C. difficile TcdA and TcdB reveal unexpected neutralizing epitopes and provide a toolkit for toxin quantitation in vivo. PLoS Pathog 2023; 19:e1011496. [PMID: 37871122 PMCID: PMC10621975 DOI: 10.1371/journal.ppat.1011496] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2023] [Revised: 11/02/2023] [Accepted: 10/07/2023] [Indexed: 10/25/2023] Open
Abstract
Clostridioides difficile is a leading cause of antibiotic-associated diarrhea and nosocomial infection in the United States. The symptoms of C. difficile infection (CDI) are associated with the production of two homologous protein toxins, TcdA and TcdB. The toxins are considered bona fide targets for clinical diagnosis as well as the development of novel prevention and therapeutic strategies. While there are extensive studies that document these efforts, there are several gaps in knowledge that could benefit from the creation of new research tools. First, we now appreciate that while TcdA sequences are conserved, TcdB sequences can vary across the span of circulating clinical isolates. An understanding of the TcdA and TcdB epitopes that drive broadly neutralizing antibody responses could advance the effort to identify safe and effective toxin-protein chimeras and fragments for vaccine development. Further, an understanding of TcdA and TcdB concentration changes in vivo can guide research into how host and microbiome-focused interventions affect the virulence potential of C. difficile. We have developed a panel of alpaca-derived nanobodies that bind specific structural and functional domains of TcdA and TcdB. We note that many of the potent neutralizers of TcdA bind epitopes within the delivery domain, a finding that could reflect roles of the delivery domain in receptor binding and/or the conserved role of pore-formation in the delivery of the toxin enzyme domains to the cytosol. In contrast, neutralizing epitopes for TcdB were found in multiple domains. The nanobodies were also used for the creation of sandwich ELISA assays that allow for quantitation of TcdA and/or TcdB in vitro and in the cecal and fecal contents of infected mice. We anticipate these reagents and assays will allow researchers to monitor the dynamics of TcdA and TcdB production over time, and the impact of various experimental interventions on toxin production in vivo.
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Affiliation(s)
- Shannon L. Kordus
- Department of Pathology, Microbiology, and Immunology, Vanderbilt University Medical Center, Nashville, Tennessee, United States of America
| | - Heather K. Kroh
- Department of Pathology, Microbiology, and Immunology, Vanderbilt University Medical Center, Nashville, Tennessee, United States of America
| | - Rubén Cano Rodríguez
- Department of Pathology, Microbiology, and Immunology, Vanderbilt University Medical Center, Nashville, Tennessee, United States of America
| | - Rebecca A. Shrem
- Department of Pharmacology, Vanderbilt University, Nashville, Tennessee, United States of America
| | - F. Christopher Peritore-Galve
- Department of Pathology, Microbiology, and Immunology, Vanderbilt University Medical Center, Nashville, Tennessee, United States of America
| | - John A. Shupe
- Department of Pathology, Microbiology, and Immunology, Vanderbilt University Medical Center, Nashville, Tennessee, United States of America
| | - Brian E. Wadzinski
- Department of Pharmacology, Vanderbilt University, Nashville, Tennessee, United States of America
| | - D. Borden Lacy
- Department of Pathology, Microbiology, and Immunology, Vanderbilt University Medical Center, Nashville, Tennessee, United States of America
- Department of Veterans Affairs, Tennessee Valley Healthcare System, Nashville, Tennessee, United States of America
| | - Benjamin W. Spiller
- Department of Pathology, Microbiology, and Immunology, Vanderbilt University Medical Center, Nashville, Tennessee, United States of America
- Department of Pharmacology, Vanderbilt University, Nashville, Tennessee, United States of America
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18
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Tian S, Zhou N. Gaining New Insights into Fundamental Biological Pathways by Bacterial Toxin-Based Genetic Screens. Bioengineering (Basel) 2023; 10:884. [PMID: 37627769 PMCID: PMC10451959 DOI: 10.3390/bioengineering10080884] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2023] [Revised: 07/11/2023] [Accepted: 07/22/2023] [Indexed: 08/27/2023] Open
Abstract
Genetic screen technology has been applied to study the mechanism of action of bacterial toxins-a special class of virulence factors that contribute to the pathogenesis caused by bacterial infections. These screens aim to identify host factors that directly or indirectly facilitate toxin intoxication. Additionally, specific properties of certain toxins, such as membrane interaction, retrograde trafficking, and carbohydrate binding, provide robust probes to comprehensively investigate the lipid biosynthesis, membrane vesicle transport, and glycosylation pathways, respectively. This review specifically focuses on recent representative toxin-based genetic screens that have identified new players involved in and provided new insights into fundamental biological pathways, such as glycosphingolipid biosynthesis, protein glycosylation, and membrane vesicle trafficking pathways. Functionally characterizing these newly identified factors not only expands our current understanding of toxin biology but also enables a deeper comprehension of fundamental biological questions. Consequently, it stimulates the development of new therapeutic approaches targeting both bacterial infectious diseases and genetic disorders with defects in these factors and pathways.
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Affiliation(s)
- Songhai Tian
- State Key Laboratory of Natural and Biomimetic Drugs, Department of Molecular and Cellular Pharmacology, School of Pharmaceutical Sciences, Peking University, 38 Xueyuan Road, Beijing 100191, China
- Department of Urology, Boston Children’s Hospital, Boston, MA 02115, USA;
- Department of Microbiology and Department of Surgery, Harvard Medical School, Boston, MA 02115, USA
| | - Nini Zhou
- Department of Urology, Boston Children’s Hospital, Boston, MA 02115, USA;
- Department of Microbiology and Department of Surgery, Harvard Medical School, Boston, MA 02115, USA
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19
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Abstract
The mucosal lining of the gut has co-evolved with a diverse microbiota over millions of years, leading to the development of specialized mechanisms to actively limit the invasion of pathogens. However, some enteric microorganisms have adapted against these measures, developing ways to hijack or overcome epithelial micro-integrity mechanisms. This breach of the gut barrier not only enables the leakage of host factors out of circulation but can also initiate a cascade of detrimental systemic events as microbiota, pathogens and their affiliated secretions passively leak into extra-intestinal sites. Under normal circumstances, gut damage is rapidly repaired by intestinal stem cells. However, with substantial and deep perturbation to the gut lining and the systemic dissemination of gut contents, we now know that some enteric infections can cause the impairment of host regenerative processes. Although these local and systemic aspects of enteric disease are often studied in isolation, they heavily impact one another. In this Review, by examining the journey of enteric infections from initial establishment to systemic sequelae and how, or if, the host can successfully repair damage, we will tie together these complex interactions to provide a holistic overview of the impact of enteric infections at and beyond the epithelial barrier.
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Affiliation(s)
- Ashleigh P Rogers
- Infection and Immunity Program, Monash Biomedicine Discovery Institute, Monash University, Melbourne, Victoria, Australia.,Department of Microbiology, Monash University, Melbourne, Victoria, Australia
| | - Steven J Mileto
- Infection and Immunity Program, Monash Biomedicine Discovery Institute, Monash University, Melbourne, Victoria, Australia.,Department of Microbiology, Monash University, Melbourne, Victoria, Australia
| | - Dena Lyras
- Infection and Immunity Program, Monash Biomedicine Discovery Institute, Monash University, Melbourne, Victoria, Australia. .,Department of Microbiology, Monash University, Melbourne, Victoria, Australia.
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20
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Larabee JL, Doyle DA, Ahmed UKB, Shadid TM, Sharp RR, Jones KL, Kim YM, Li S, Ballard JD. Discovery of Hippo signaling as a regulator of CSPG4 expression and as a therapeutic target for Clostridioides difficile disease. PLoS Pathog 2023; 19:e1011272. [PMID: 36972308 PMCID: PMC10079225 DOI: 10.1371/journal.ppat.1011272] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2023] [Revised: 04/06/2023] [Accepted: 03/08/2023] [Indexed: 03/29/2023] Open
Abstract
The signaling pathways and networks regulating expression of chondroitin sulfate proteoglycan 4 (CSPG4), a cancer-related protein that serves as a receptor for Clostridiodes difficile TcdB, are poorly defined. In this study, TcdB-resistant/CSPG4-negative HeLa cells were generated by exposure to increasing concentrations of the toxin. The cells that emerged (HeLa R5) lost expression of CSPG4 mRNA and were resistant to binding by TcdB. mRNA expression profiles paired with integrated pathway analysis correlated changes in the Hippo and estrogen signaling pathways with a CSPG4 decrease in HeLa R5 cells. Both signaling pathways altered CSPG4 expression when modulated chemically or through CRISPR-mediated deletion of key transcriptional regulators in the Hippo pathway. Based on the in vitro findings, we predicted and experimentally confirmed that a Hippo pathway inactivating drug (XMU-MP-1) provides protection from C. difficile disease in a mouse model. These results provide insights into key regulators of CSPG4 expression and identify a therapeutic for C. difficile disease.
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Affiliation(s)
- Jason L. Larabee
- Department of Microbiology and Immunology, The University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma, United States of America
| | - D. Annie Doyle
- Department of Microbiology and Immunology, The University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma, United States of America
| | - Ummey Khalecha Bintha Ahmed
- Department of Microbiology and Immunology, The University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma, United States of America
| | - Tyler M. Shadid
- Department of Microbiology and Immunology, The University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma, United States of America
| | - Rachel R. Sharp
- Laboratory for Molecular Biology and Cytometry Research, Harold Hamm Diabetes Center, Oklahoma City, Oklahoma, United States of America
| | - Kenneth L. Jones
- Laboratory for Molecular Biology and Cytometry Research, Harold Hamm Diabetes Center, Oklahoma City, Oklahoma, United States of America
- Department of Cell Biology, The University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma, United States of America
| | - Young Mi Kim
- Department of Pediatrics, The University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma, United States of America
| | - Shibo Li
- Department of Pediatrics, The University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma, United States of America
| | - Jimmy D. Ballard
- Department of Microbiology and Immunology, The University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma, United States of America
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21
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Lambo DJ, Lebedenko CG, McCallum PA, Banerjee IA. Molecular dynamics, MMGBSA, and docking studies of natural products conjugated to tumor-targeted peptide for targeting BRAF V600E and MERTK receptors. Mol Divers 2023; 27:389-423. [PMID: 35505173 DOI: 10.1007/s11030-022-10430-8] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2022] [Accepted: 03/31/2022] [Indexed: 02/08/2023]
Abstract
Recent studies have revealed that MERTK and BRAF V600E receptors have been found to be over-expressed in several types of cancers including melanoma, making these receptors targets for drug design. In this study, we have designed novel peptide conjugates with the natural products vanillic acid, thiazole-2-carboxylic acid, cinnamic acid, theanine, and protocatechuic acid. Each of these compounds was conjugated with the tumor targeting peptide sequence TAASGVRSMH, known to bind to NG2 and target tumor neovasculature. We examined their binding affinities and stability with MERTK and BRAF V600E receptors using molecular docking and molecular dynamics studies. Compared to the neat compounds, the peptide conjugates displayed higher binding affinity toward both receptors. In the case of MERTK, the most stable complexes were formed with di-theaninate-peptide, vanillate-peptide, and thiazole-2-amido peptide conjugates and binding occurred in the hinge region. Additionally, it was discovered that the peptide alone also had high binding ability and stability with the MERTK receptor. In the case of BRAF V600E, the peptide conjugates of protocatechuate, vanillate and thiazole-2-amido peptide conjugates showed the formation of the most stable complexes and binding occurred in the ATP binding cleft. Further analysis revealed that the number of hydrogen bonds and hydrophobic interactions played a critical role in enhanced stability of the complexes. Docking studies also revealed that binding affinities for NG2 were similar to MERTK and higher for BRAF V600E. MMGBSA studies of the trajectories revealed that the protocatechuate-peptide conjugate showed the highest binding energy with BRAF V600E while the peptide-TAASGVRSMH showed the highest binding energy with MERTK. ADME studies revealed that each of the compounds showed medium to high permeability toward MDCK cells and were not hERG blockers. Furthermore, the conjugates were not CYP inhibitors or substrates, but they were found to be Pgp substrates. Our results indicated that the protocatechuate-TAASGVRSMH, thiazole-2-amido-TAASGVRSMH, and vanillate-TAASGVRSMH conjugates may be furthered developed for in vitro and in vivo studies as novel tumor targeting compounds for tumor cells over-expressing BRAF V600E, while di-theaninate-amido-TAASGVRSMH and thiazole-2-amido-TAASGVRSMH conjugates may be developed for targeting MERTK receptors. These studies provide insight into the molecular interactions of natural product-peptide conjugates and their potential for binding to and targeting MERTK and BRAF V600E receptors in developing new therapeutics for targeting cancer.
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Affiliation(s)
- Dominic J Lambo
- Department of Chemistry, Fordham University, 441 E. Fordham Rd, Bronx, NY, 10458, USA
| | - Charlotta G Lebedenko
- Department of Chemistry, Fordham University, 441 E. Fordham Rd, Bronx, NY, 10458, USA
| | - Paige A McCallum
- Department of Chemistry, Fordham University, 441 E. Fordham Rd, Bronx, NY, 10458, USA
| | - Ipsita A Banerjee
- Department of Chemistry, Fordham University, 441 E. Fordham Rd, Bronx, NY, 10458, USA.
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22
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Chen P, Jin R. Receptor binding mechanisms of Clostridioides difficile toxin B and implications for therapeutics development. FEBS J 2023; 290:962-969. [PMID: 34862749 PMCID: PMC9344982 DOI: 10.1111/febs.16310] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2021] [Revised: 11/19/2021] [Accepted: 12/02/2021] [Indexed: 12/29/2022]
Abstract
Clostridioides difficile is classified as an urgent antibiotic resistance threat by the Centers for Disease Control and Prevention (CDC). C. difficile infection (CDI) is mainly caused by the C. difficile exotoxin TcdB, which invades host cells via receptor-mediated endocytosis. However, many natural variants of TcdB have been identified including some from the hypervirulent strains, which pose significant challenges for developing effective CDI therapies. Here, we review the recent research progress on the molecular mechanisms by which TcdB recognizes Frizzed proteins (FZDs) and chondroitin sulfate proteoglycan 4 (CSPG4) as two major host receptors. We suggest that the receptor-binding sites and several previously identified neutralizing epitopes on TcdB are ideal targets for the development of broad-spectrum inhibitors to protect against diverse TcdB variants.
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Affiliation(s)
- Peng Chen
- Department of Physiology and Biophysics, University of California Irvine, Irvine, California, 92697, USA
| | - Rongsheng Jin
- Department of Physiology and Biophysics, University of California Irvine, Irvine, California, 92697, USA
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23
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Bernard SC, Washington MK, Lacy DB. Paeniclostridium sordellii uterine infection is dependent on the estrous cycle. PLoS Pathog 2022; 18:e1010997. [PMID: 36409774 PMCID: PMC9721474 DOI: 10.1371/journal.ppat.1010997] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2022] [Revised: 12/05/2022] [Accepted: 11/10/2022] [Indexed: 11/22/2022] Open
Abstract
Human infections caused by the toxin-producing, anaerobic and spore-forming bacterium Paeniclostridium sordellii are associated with a treatment-refractory toxic shock syndrome (TSS). Reproductive-age women are at increased risk for P. sordellii infection (PSI) because this organism can cause intrauterine infection following childbirth, stillbirth, or abortion. PSI-induced TSS in this setting is nearly 100% fatal, and there are no effective treatments. TcsL, or lethal toxin, is the primary virulence factor in PSI and shares 70% sequence identity with Clostridioides difficile toxin B (TcdB). We therefore reasoned that a neutralizing monoclonal antibody (mAB) against TcdB might also provide protection against TcsL and PSI. We characterized two anti-TcdB mABs: PA41, which binds and prevents translocation of the TcdB glucosyltransferase domain into the cell, and CDB1, a biosimilar of bezlotoxumab, which prevents TcdB binding to a cell surface receptor. Both mABs could neutralize the cytotoxic activity of recombinant TcsL on Vero cells. To determine the efficacy of PA41 and CDB1 in vivo, we developed a transcervical inoculation method for modeling uterine PSI in mice. In the process, we discovered that the stage of the mouse reproductive cycle was a key variable in establishing symptoms of disease. By synchronizing the mice in diestrus with progesterone prior to transcervical inoculation with TcsL or vegetative P. sordellii, we observed highly reproducible intoxication and infection dynamics. PA41 showed efficacy in protecting against toxin in our transcervical in vivo model, but CDB1 did not. Furthermore, PA41 could provide protection following P. sordellii bacterial and spore infections, suggesting a path for further optimization and clinical translation in the effort to advance treatment options for PSI infection.
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Affiliation(s)
- Sarah C. Bernard
- Department of Pathology, Microbiology, and Immunology, Vanderbilt University Medical Center, Nashville, Tennessee, United States of America
| | - M. Kay Washington
- Department of Pathology, Microbiology, and Immunology, Vanderbilt University Medical Center, Nashville, Tennessee, United States of America
| | - D. Borden Lacy
- Department of Pathology, Microbiology, and Immunology, Vanderbilt University Medical Center, Nashville, Tennessee, United States of America
- Veterans Affairs Tennessee Valley Healthcare System, Nashville, Tennessee, United States of America
- * E-mail:
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24
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Chen B, Perry K, Jin R. Neutralizing epitopes on Clostridioides difficile toxin A revealed by the structures of two camelid VHH antibodies. Front Immunol 2022; 13:978858. [PMID: 36466927 PMCID: PMC9709291 DOI: 10.3389/fimmu.2022.978858] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2022] [Accepted: 10/31/2022] [Indexed: 11/18/2022] Open
Abstract
Toxin A (TcdA) and toxin B (TcdB) are two key virulence factors secreted by Clostridioides difficile, which is listed as an urgent threat by the CDC. These two large homologous exotoxins are mainly responsible for diseases associated with C. difficile infection (CDI) with symptoms ranging from diarrhea to life threatening pseudomembranous colitis. Single-domain camelid antibodies (VHHs) AH3 and AA6 are two potent antitoxins against TcdA, which when combined with two TcdB-targeting VHHs showed effective protection against both primary and recurrent CDI in animal models. Here, we report the co-crystal structures of AH3 and AA6 when they form complexes with the glucosyltransferase domain (GTD) and a fragment of the delivery and receptor-binding domain (DRBD) of TcdA, respectively. Based on these structures, we find that AH3 binding enhances the overall stability of the GTD and interferes with its unfolding at acidic pH, and AA6 may inhibit the pH-dependent conformational changes in the DRBD that is necessary for pore formation of TcdA. These studies reveal two functionally critical epitopes on TcdA and shed new insights into neutralizing mechanisms and potential development of epitope-focused vaccines against TcdA.
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Affiliation(s)
- Baohua Chen
- Department of Physiology and Biophysics, School of Medicine, University of California, Irvine, CA, United States
| | - Kay Perry
- NE-CAT, Advanced Photon Source, Argonne National Laboratory, Argonne, IL, United States,Department of Chemistry and Chemical Biology, Cornell University, Argonne, IL, United States
| | - Rongsheng Jin
- Department of Physiology and Biophysics, School of Medicine, University of California, Irvine, CA, United States,*Correspondence: Rongsheng Jin,
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25
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Zhang F, Yang P, Chen Y, Wang R, Liu B, Wang J, Yuan M, Zhang L. Bibliometric and visual analysis of fecal microbiota transplantation research from 2012 to 2021. Front Cell Infect Microbiol 2022; 12:1057492. [PMID: 36439220 PMCID: PMC9684174 DOI: 10.3389/fcimb.2022.1057492] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2022] [Accepted: 10/26/2022] [Indexed: 09/08/2023] Open
Abstract
BACKGROUND Fecal microbiota transplantation (FMT) is an emerging therapy for diseases associated with intestinal flora imbalance that has attracted increasing attention in recent years. This study aims to provide an overview of research trends in the field, and act as a reference point for future scientific research by analyzing the state of current research, identifying hotspots, and potential frontiers of FMT. METHODS Articles relating to FMT that were published between the years 2012 and 2021 were retrieved from the Web of Science Core Collection. Bibliometric analysis was performed using Microsoft Excel and CiteSpace. RESULTS A total of 2,403 English language articles relating to FMT research were published over the last ten years. Most of this research was carried out in the United States of America, with Harvard Medical school being the most productive institution. Much of the research was published in the PLoS One journal. Alexander Khoruts was identified as a prominent, productive researcher in the field. Keyword analysis revealed that research hot spots included gut microbiota, Clostridium difficile infection (CDI), and diseases. Burst detection indicated that future research frontiers include clinical practice guidelines and strategies. CONCLUSION Our analysis explored hot spots and emerging trends in the FMT field. Indications for use of FMT extended from digestive system diseases to other systemic diseases. Additionally, areas such as risk assessment and control, along with application methods were also a focus of current research. Moreover, research relating to optimization of clinical practice has excellent prospects.
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Affiliation(s)
| | | | | | | | | | | | - Min Yuan
- Shanghai Innovation Center of TCM Health Service, Shanghai University of Traditional Chinese Medicine, Shanghai, China
| | - Lei Zhang
- Shanghai Innovation Center of TCM Health Service, Shanghai University of Traditional Chinese Medicine, Shanghai, China
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26
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Zhou Y, Li D, Li D, Chen A, He L, Luo J, Tao L. LDLR, LRP1, and Megalin redundantly participate in the uptake of Clostridium novyi alpha-toxin. Commun Biol 2022; 5:906. [PMID: 36064583 DOI: 10.1038/s42003-022-03873-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2021] [Accepted: 08/23/2022] [Indexed: 11/30/2022] Open
Abstract
Clostridium novyi alpha-toxin (Tcnα) is a potent exotoxin that induces severe symptoms including gas gangrene, myositis, necrotic hepatitis, and sepsis. Tcnα binds to sulfated glycosaminoglycans (sGAG) for cell-surface attachment and utilizes low-density lipoprotein receptor (LDLR) for rapid entry. However, it was also shown that Tcnα may use alternative entry receptors other than LDLR. Here, we define that LRP1 and Megalin can also facilitate the cellular entry of Tcnα by employing reconstitutive LDLR family proteins. LDLR, LRP1, and Megalin recognize Tcnα via their ligand-binding domains (also known as LDL receptor type A repeats). Notably, LDLR and LRP1 have contrasting expression levels in many different cells, thus the dominant entry receptor for Tcnα could be cell-type dependent. These findings together increase our knowledge of the Tcnα actions and further help to understand the pathogenesis of C. novyi infection-associated diseases. Clostridium novyi alpha-toxin (Tcnα) also uses LRP1 and Megalin as cellular entry receptors besides LDLR, and this might be a response to cell-type dependent receptor availability for the exotoxin.
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27
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Zeng J, Wang H, Dong M, Tian GB. Clostridioides difficile spore: coat assembly and formation. Emerg Microbes Infect 2022; 11:2340-2349. [PMID: 36032037 PMCID: PMC9542656 DOI: 10.1080/22221751.2022.2119168] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
Clostridioides difficile (C. difficile) is a Gram-positive, spore-forming, toxin-producing, obligate anaerobic bacterium. C. difficile infection (CDI) is the leading cause of healthcare-associated infective diarrhoea. The infection is mediated by the spore, a metabolically inactive form of C. difficile. The spore coat acts as a physical barrier to defend against chemical insults from hosts and natural environments. The composition of spore coat has already been revealed; therefore, the interactive networks of spore coat proteins and the dynamic process of coat assembly are the keys to design strategies to control and cure CDI. This review gives a brief discussion of the signal processing and transcriptional regulation of C. difficile sporulation initiation. Following the discussion, the spore formation is also introduced. Finally, this review mainly focuses on the spore coat assembly, a poorly understood process in C. difficile, and important proteins that have been studied.
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Affiliation(s)
- Ji Zeng
- School of Biomedical and Pharmaceutical Sciences, Guangdong University of Technology, Guangzhou, Guangdong 510006, China
| | - Hao Wang
- School of Biomedical and Pharmaceutical Sciences, Guangdong University of Technology, Guangzhou, Guangdong 510006, China
| | - Min Dong
- Department of Microbiology, Harvard Medical School, Boston, MA, USA
- Department of Urology, Boston Children’s Hospital, Harvard Medical School, Boston, MA, USA
| | - Guo-Bao Tian
- Department of Microbiology, Zhongshan School of Medicine, Sun Yat-sen University, Guangdong 510080, China
- Advanced Medical Technology Center, The First Affiliated Hospital, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou 510080, China
- Key Laboratory of Tropical Diseases Control (Sun Yat-sen University), Ministry of Education, Guangzhou 510080, China
- School of Medicine, Xizang Minzu University, Xianyang, Shaanxi 712082, China
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28
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Li X, He L, Luo J, Zheng Y, Zhou Y, Li D, Zhang Y, Pan Z, Li Y, Tao L. Paeniclostridium sordellii hemorrhagic toxin targets TMPRSS2 to induce colonic epithelial lesions. Nat Commun 2022; 13:4331. [PMID: 35882856 DOI: 10.1038/s41467-022-31994-x] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2022] [Accepted: 07/12/2022] [Indexed: 12/21/2022] Open
Abstract
Hemorrhagic toxin (TcsH) is an important exotoxin produced by Paeniclostridium sordellii, but the exact role of TcsH in the pathogenesis remains unclear, partly due to the lack of knowledge of host receptor(s). Here, we carried out two genome-wide CRISPR/Cas9 screens parallelly with TcsH and identified cell surface fucosylation and TMPRSS2 as host factors contributing to the binding and entry of TcsH. Genetic deletion of either fucosylation biosynthesis enzymes or TMPRSS2 in the cells confers resistance to TcsH intoxication. Interestingly, TMPRSS2 and fucosylated glycans can mediate the binding/entry of TcsH independently, thus serving as redundant receptors. Both TMPRSS2 and fucosylation recognize TcsH through its CROPs domain. By using Tmprss2‒/‒ mice, we show that Tmprss2 is important for TcsH-induced systematic toxicity and colonic epithelial lesions. These findings reveal the importance of TMPRSS2 and surface fucosylation in TcsH actions and further provide insights into host recognition mechanisms for large clostridial toxins. Paeniclostridium sordellii is an opportunistic pathogen that can occur and be fatal in women undergoing abortion or childbirth. The pathogenesis of a hemorrhagic toxin, TcsH, produced by this bacteria, remains unknown. Here, authors carry out genome-wide screens to identify pathologically relevant host factors of TcsH.
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29
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Wu Y, Mahtal N, Paillares E, Swistak L, Sagadiev S, Acharya M, Demeret C, Werf SV, Guivel-Benhassine F, Schwartz O, Petracchini S, Mettouchi A, Caramelle L, Couvineau P, Thai R, Barbe P, Keck M, Brodin P, Machelart A, Sencio V, Trottein F, Sachse M, Chicanne G, Payrastre B, Ville F, Kreis V, Popoff MR, Johannes L, Cintrat JC, Barbier J, Gillet D, Lemichez E. C910 chemical compound inhibits the traffiking of several bacterial AB toxins with cross-protection against influenza virus. iScience 2022; 25:104537. [PMID: 35769882 DOI: 10.1016/j.isci.2022.104537] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2021] [Revised: 04/20/2022] [Accepted: 06/01/2022] [Indexed: 11/23/2022] Open
Abstract
The development of anti-infectives against a large range of AB-like toxin-producing bacteria includes the identification of compounds disrupting toxin transport through both the endolysosomal and retrograde pathways. Here, we performed a high-throughput screening of compounds blocking Rac1 proteasomal degradation triggered by the Cytotoxic Necrotizing Factor-1 (CNF1) toxin, which was followed by orthogonal screens against two toxins that hijack the endolysosomal (diphtheria toxin) or retrograde (Shiga-like toxin 1) pathways to intoxicate cells. This led to the identification of the molecule C910 that induces the enlargement of EEA1-positive early endosomes associated with sorting defects of CNF1 and Shiga toxins to their trafficking pathways. C910 protects cells against eight bacterial AB toxins and the CNF1-mediated pathogenic Escherichia coli invasion. Interestingly, C910 reduces influenza A H1N1 and SARS-CoV-2 viral infection in vitro. Moreover, parenteral administration of C910 to mice resulted in its accumulation in lung tissues and a reduction in lethal influenza infection. Screen for inhibitors disrupting bacterial AB toxins vesicular trafficking pathways C910 affects EEA1/Rab5-positive early endosome morphology and sorting functions C910 protects cells against eight AB toxins, SARS-CoV-2 and influenza A virus C910 accumulates in lung tissues and protects mice against influenza A virus
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30
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Chen B, Liu Z, Perry K, Jin R. Structure of the glucosyltransferase domain of TcdA in complex with RhoA provides insights into substrate recognition. Sci Rep 2022; 12:9028. [PMID: 35637242 PMCID: PMC9151644 DOI: 10.1038/s41598-022-12909-8] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2022] [Accepted: 05/17/2022] [Indexed: 01/05/2023] Open
Abstract
Clostridioides difficile is one of the most common causes of antibiotic-associated diarrhea in developed countries. As key virulence factors of C. difficile, toxin A (TcdA) and toxin B (TcdB) act by glucosylating and inactivating Rho and Ras family small GTPases in host cells, which leads to actin cytoskeleton disruption, cell rounding, and ultimately cell death. Here we present the co-crystal structure of the glucosyltransferase domain (GTD) of TcdA in complex with its substrate human RhoA at 2.60-angstrom resolution. This structure reveals that TcdA GTD grips RhoA mainly through its switch I and switch II regions, which is complemented by interactions involving RhoA's pre-switch I region. Comprehensive structural comparisons between the TcdA GTD-RhoA complex and the structures of TcdB GTD in complex with Cdc42 and R-Ras reveal both the conserved and divergent features of these two toxins in terms of substrate recognition. Taken together, these findings establish the structural basis for TcdA recognition of small GTPases and advance our understanding of the substrates selectivity of large clostridial toxins.
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Affiliation(s)
- Baohua Chen
- Department of Physiology and Biophysics, School of Medicine, University of California, Irvine, CA, 92697, USA
| | - Zheng Liu
- Department of Physiology and Biophysics, School of Medicine, University of California, Irvine, CA, 92697, USA
| | - Kay Perry
- NE-CAT and Department of Chemistry and Chemical Biology, Argonne National Laboratory, Cornell University, Argonne, IL, 60439, USA
| | - Rongsheng Jin
- Department of Physiology and Biophysics, School of Medicine, University of California, Irvine, CA, 92697, USA.
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Abstract
Clostridioides difficile is a Gram-positive anaerobe that can cause a spectrum of disorders that range in severity from mild diarrhoea to fulminant colitis and/or death. The bacterium produces up to three toxins, which are considered the major virulence factors in C. difficile infection. These toxins promote inflammation, tissue damage and diarrhoea. In this Review, we highlight recent biochemical and structural advances in our understanding of the mechanisms that govern host-toxin interactions. Understanding how C. difficile toxins affect the host forms a foundation for developing novel strategies for treatment and prevention of C. difficile infection.
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Affiliation(s)
- Shannon L. Kordus
- Department of Pathology, Microbiology, and Immunology, Vanderbilt University Medical Center, Nashville, TN, USA,Center for Structural Biology, Vanderbilt University, Nashville, TN, USA,These authors contributed equally: Shannon L. Kordus, Audrey K. Thomas
| | - Audrey K. Thomas
- Department of Pathology, Microbiology, and Immunology, Vanderbilt University Medical Center, Nashville, TN, USA,Center for Structural Biology, Vanderbilt University, Nashville, TN, USA,These authors contributed equally: Shannon L. Kordus, Audrey K. Thomas
| | - D. Borden Lacy
- Department of Pathology, Microbiology, and Immunology, Vanderbilt University Medical Center, Nashville, TN, USA,Center for Structural Biology, Vanderbilt University, Nashville, TN, USA,The Veterans Affairs, Tennessee Valley Healthcare, System, Nashville, TN, USA,
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32
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Chen B, Basak S, Chen P, Zhang C, Perry K, Tian S, Yu C, Dong M, Huang L, Bowen ME, Jin R. Structure and conformational dynamics of Clostridioides difficile toxin A. Life Sci Alliance 2022; 5:5/6/e202201383. [PMID: 35292538 PMCID: PMC8924006 DOI: 10.26508/lsa.202201383] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2022] [Revised: 02/25/2022] [Accepted: 02/28/2022] [Indexed: 01/05/2023] Open
Abstract
This study presents a complete structural model of TcdA holotoxin and sheds new lights into the conformational dynamics of TcdA and its roles in TcdA intoxication. Clostridioides difficile toxin A and B (TcdA and TcdB) are two major virulence factors responsible for diseases associated with C. difficile infection (CDI). Here, we report the 3.18-Å resolution crystal structure of a TcdA fragment (residues L843–T2481), which advances our understanding of the complete structure of TcdA holotoxin. Our structural analysis, together with complementary single molecule FRET and limited proteolysis studies, reveal that TcdA adopts a dynamic structure and its CROPs domain can sample a spectrum of open and closed conformations in a pH-dependent manner. Furthermore, a small globular subdomain (SGS) and the CROPs protect the pore-forming region of TcdA in the closed state at neutral pH, which could contribute to modulating the pH-dependent pore formation of TcdA. A rationally designed TcdA mutation that trapped the CROPs in the closed conformation showed drastically reduced cytotoxicity. Taken together, these studies shed new lights into the conformational dynamics of TcdA and its roles in TcdA intoxication.
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Affiliation(s)
- Baohua Chen
- Department of Physiology and Biophysics, School of Medicine, University of California, Irvine, Irvine, CA, USA
| | - Sujit Basak
- Department of Physiology and Biophysics, Stony Brook University, Stony Brook, NY, USA
| | - Peng Chen
- Department of Physiology and Biophysics, School of Medicine, University of California, Irvine, Irvine, CA, USA
| | - Changcheng Zhang
- Department of Physiology and Biophysics, Stony Brook University, Stony Brook, NY, USA
| | - Kay Perry
- NE-CAT and Department of Chemistry and Chemical Biology, Cornell University, Argonne National Laboratory, Argonne, IL, USA
| | - Songhai Tian
- Department of Urology, Boston Children's Hospital, Department of Microbiology and Department of Surgery, Harvard Medical School, Boston, MA, USA
| | - Clinton Yu
- Department of Physiology and Biophysics, School of Medicine, University of California, Irvine, Irvine, CA, USA
| | - Min Dong
- Department of Urology, Boston Children's Hospital, Department of Microbiology and Department of Surgery, Harvard Medical School, Boston, MA, USA
| | - Lan Huang
- Department of Physiology and Biophysics, School of Medicine, University of California, Irvine, Irvine, CA, USA
| | - Mark E Bowen
- Department of Physiology and Biophysics, Stony Brook University, Stony Brook, NY, USA
| | - Rongsheng Jin
- Department of Physiology and Biophysics, School of Medicine, University of California, Irvine, Irvine, CA, USA
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Luo J, Yang Q, Zhang X, Zhang Y, Wan L, Zhan X, Zhou Y, He L, Li D, Jin D, Zhen Y, Huang J, Li Y, Tao L. TFPI is a colonic crypt receptor for TcdB from hypervirulent clade 2 C. difficile. Cell 2022; 185:980-994.e15. [PMID: 35303428 DOI: 10.1016/j.cell.2022.02.010] [Citation(s) in RCA: 25] [Impact Index Per Article: 12.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2021] [Revised: 01/11/2022] [Accepted: 02/08/2022] [Indexed: 12/14/2022]
Abstract
The emergence of hypervirulent clade 2 Clostridioides difficile is associated with severe symptoms and accounts for >20% of global infections. TcdB is a dominant virulence factor of C. difficile, and clade 2 strains exclusively express two TcdB variants (TcdB2 and TcdB4) that use unknown receptors distinct from the classic TcdB. Here, we performed CRISPR/Cas9 screens for TcdB4 and identified tissue factor pathway inhibitor (TFPI) as its receptor. Using cryo-EM, we determined a complex structure of the full-length TcdB4 with TFPI, defining a common receptor-binding region for TcdB. Residue variations within this region divide major TcdB variants into 2 classes: one recognizes Frizzled (FZD), and the other recognizes TFPI. TFPI is highly expressed in the intestinal glands, and recombinant TFPI protects the colonic epithelium from TcdB2/4. These findings establish TFPI as a colonic crypt receptor for TcdB from clade 2 C. difficile and reveal new mechanisms for CDI pathogenesis.
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Affiliation(s)
- Jianhua Luo
- Key Laboratory of Structural Biology of Zhejiang Province, School of Life Sciences, Westlake University, Hangzhou, Zhejiang 310024, China; Center for Infectious Disease Research, Westlake Laboratory of Life Sciences and Biomedicine, Hangzhou, Zhejiang 310024, China; Institute of Basic Medical Sciences, Westlake Institute for Advanced Study, Hangzhou, Zhejiang 310024, China
| | - Qi Yang
- Key Laboratory of Structural Biology of Zhejiang Province, School of Life Sciences, Westlake University, Hangzhou, Zhejiang 310024, China; Center for Infectious Disease Research, Westlake Laboratory of Life Sciences and Biomedicine, Hangzhou, Zhejiang 310024, China; Institute of Basic Medical Sciences, Westlake Institute for Advanced Study, Hangzhou, Zhejiang 310024, China
| | - Xiaofeng Zhang
- Key Laboratory of Structural Biology of Zhejiang Province, School of Life Sciences, Westlake University, Hangzhou, Zhejiang 310024, China; Center for Infectious Disease Research, Westlake Laboratory of Life Sciences and Biomedicine, Hangzhou, Zhejiang 310024, China; Institute of Biology, Westlake Institute for Advanced Study, Hangzhou, Zhejiang 310024, China
| | - Yuanyuan Zhang
- Key Laboratory of Structural Biology of Zhejiang Province, School of Life Sciences, Westlake University, Hangzhou, Zhejiang 310024, China; Center for Infectious Disease Research, Westlake Laboratory of Life Sciences and Biomedicine, Hangzhou, Zhejiang 310024, China; Institute of Basic Medical Sciences, Westlake Institute for Advanced Study, Hangzhou, Zhejiang 310024, China; School of Food Science and Biotechnology Engineering, Zhejiang Gongshang University, Hangzhou, Zhejiang 310018, China
| | - Li Wan
- Key Laboratory of Structural Biology of Zhejiang Province, School of Life Sciences, Westlake University, Hangzhou, Zhejiang 310024, China; Center for Infectious Disease Research, Westlake Laboratory of Life Sciences and Biomedicine, Hangzhou, Zhejiang 310024, China; Institute of Biology, Westlake Institute for Advanced Study, Hangzhou, Zhejiang 310024, China
| | - Xiechao Zhan
- Key Laboratory of Structural Biology of Zhejiang Province, School of Life Sciences, Westlake University, Hangzhou, Zhejiang 310024, China; Center for Infectious Disease Research, Westlake Laboratory of Life Sciences and Biomedicine, Hangzhou, Zhejiang 310024, China; Institute of Biology, Westlake Institute for Advanced Study, Hangzhou, Zhejiang 310024, China
| | - Yao Zhou
- Key Laboratory of Structural Biology of Zhejiang Province, School of Life Sciences, Westlake University, Hangzhou, Zhejiang 310024, China; Center for Infectious Disease Research, Westlake Laboratory of Life Sciences and Biomedicine, Hangzhou, Zhejiang 310024, China; Institute of Basic Medical Sciences, Westlake Institute for Advanced Study, Hangzhou, Zhejiang 310024, China
| | - Liuqing He
- Key Laboratory of Structural Biology of Zhejiang Province, School of Life Sciences, Westlake University, Hangzhou, Zhejiang 310024, China; Center for Infectious Disease Research, Westlake Laboratory of Life Sciences and Biomedicine, Hangzhou, Zhejiang 310024, China; Institute of Basic Medical Sciences, Westlake Institute for Advanced Study, Hangzhou, Zhejiang 310024, China
| | - Danyang Li
- Key Laboratory of Structural Biology of Zhejiang Province, School of Life Sciences, Westlake University, Hangzhou, Zhejiang 310024, China; Center for Infectious Disease Research, Westlake Laboratory of Life Sciences and Biomedicine, Hangzhou, Zhejiang 310024, China; Institute of Basic Medical Sciences, Westlake Institute for Advanced Study, Hangzhou, Zhejiang 310024, China
| | - Dazhi Jin
- Center of Laboratory Medicine, Zhejiang Provincial People's Hospital, People's Hospital of Hangzhou Medical College, Hangzhou, Zhejiang 310014, China; School of Laboratory Medicine, Hangzhou Medical College, Hangzhou, Zhejiang 310014, China
| | - Ying Zhen
- Key Laboratory of Structural Biology of Zhejiang Province, School of Life Sciences, Westlake University, Hangzhou, Zhejiang 310024, China; Center for Infectious Disease Research, Westlake Laboratory of Life Sciences and Biomedicine, Hangzhou, Zhejiang 310024, China; Institute of Biology, Westlake Institute for Advanced Study, Hangzhou, Zhejiang 310024, China
| | - Jing Huang
- Key Laboratory of Structural Biology of Zhejiang Province, School of Life Sciences, Westlake University, Hangzhou, Zhejiang 310024, China; Center for Infectious Disease Research, Westlake Laboratory of Life Sciences and Biomedicine, Hangzhou, Zhejiang 310024, China; Institute of Biology, Westlake Institute for Advanced Study, Hangzhou, Zhejiang 310024, China
| | - Yanyan Li
- Key Laboratory of Structural Biology of Zhejiang Province, School of Life Sciences, Westlake University, Hangzhou, Zhejiang 310024, China; Center for Infectious Disease Research, Westlake Laboratory of Life Sciences and Biomedicine, Hangzhou, Zhejiang 310024, China; Institute of Biology, Westlake Institute for Advanced Study, Hangzhou, Zhejiang 310024, China.
| | - Liang Tao
- Key Laboratory of Structural Biology of Zhejiang Province, School of Life Sciences, Westlake University, Hangzhou, Zhejiang 310024, China; Center for Infectious Disease Research, Westlake Laboratory of Life Sciences and Biomedicine, Hangzhou, Zhejiang 310024, China; Institute of Basic Medical Sciences, Westlake Institute for Advanced Study, Hangzhou, Zhejiang 310024, China.
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Jiang M, Shin J, Simeon R, Chang JY, Meng R, Wang Y, Shinde O, Li P, Chen Z, Zhang J. Structural dynamics of receptor recognition and pH-induced dissociation of full-length Clostridioides difficile Toxin B. PLoS Biol 2022; 20:e3001589. [PMID: 35324891 PMCID: PMC8982864 DOI: 10.1371/journal.pbio.3001589] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2021] [Revised: 04/05/2022] [Accepted: 03/02/2022] [Indexed: 12/14/2022] Open
Abstract
Clostridioides difficile secretes Toxin B (TcdB) as one of its major virulence factors, which binds to intestinal epithelial and subepithelial receptors, including frizzled proteins and chondroitin sulfate proteoglycan 4 (CSPG4). Here, we present cryo-EM structures of full-length TcdB in complex with the CSPG4 domain 1 fragment (D1401-560) at cytosolic pH and the cysteine-rich domain of frizzled-2 (CRD2) at both cytosolic and acidic pHs. CSPG4 specifically binds to the autoprocessing and delivery domains of TcdB via networks of salt bridges, hydrophobic and aromatic/proline interactions, which are disrupted upon acidification eventually leading to CSPG4 drastically dissociating from TcdB. In contrast, FZD2 moderately dissociates from TcdB under acidic pH, most likely due to its partial unfolding. These results reveal structural dynamics of TcdB during its preentry step upon endosomal acidification, which provide a basis for developing therapeutics against C. difficile infections.
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Affiliation(s)
- Mengqiu Jiang
- Department of Biochemistry and Biophysics, Texas A&M University, College Station, Texas, United States of America
| | - Joonyoung Shin
- Department of Biochemistry and Biophysics, Texas A&M University, College Station, Texas, United States of America
| | - Rudo Simeon
- Department of Microbial Pathogenesis and Immunology, Texas A&M University Health Science Center, College Station, Texas, United States of America
| | - Jeng-Yih Chang
- Department of Biochemistry and Biophysics, Texas A&M University, College Station, Texas, United States of America
| | - Ran Meng
- Department of Biochemistry and Biophysics, Texas A&M University, College Station, Texas, United States of America
| | - Yuhang Wang
- Department of Biochemistry and Biophysics, Texas A&M University, College Station, Texas, United States of America
| | - Omkar Shinde
- Department of Biochemistry and Biophysics, Texas A&M University, College Station, Texas, United States of America
| | - Pingwei Li
- Department of Biochemistry and Biophysics, Texas A&M University, College Station, Texas, United States of America
| | - Zhilei Chen
- Department of Microbial Pathogenesis and Immunology, Texas A&M University Health Science Center, College Station, Texas, United States of America
| | - Junjie Zhang
- Department of Biochemistry and Biophysics, Texas A&M University, College Station, Texas, United States of America
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35
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Abstract
The most common world-wide cause of antibiotic-associated infectious diarrhea and colitis is the toxin producing bacterium, Clostridioides difficile (C. difficile). Here we review the background and characteristics of the bacterium and the toxins produced together with the epidemiology and the complex pathogenesis that leads to a broad clinical spectrum of disease. The review describes the difficulties faced in obtaining a quick and accurate diagnosis despite the range of sensitive and specific diagnostic tools available. We also discuss the problem of disease recurrence and the importance of disease prevention. The high rates of infection recurrence mean that treatment strategies are constantly under review and we outline the diverse treatment options that are currently in use and explore the emerging treatment options of pulsed antibiotic use, microbial replacement therapies and the use of monoclonal antibodies. We summarize the future direction of treatment strategies which include the development of novel antibiotics, the administration of oral polyclonal antibody formulations, the use of vaccines, the administration of competitive non-toxigenic spores and the neutralization of antibiotics at the microbiota level. Future successful treatments will likely involve a combination of therapies to provide the most effective and robust approach to C. difficile management.
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Affiliation(s)
- Joanna Giles
- MicroPharm Ltd, Newcastle Emlyn, United Kingdom.
| | - April Roberts
- Toxins Group, National Infection Service, Public Health England, Porton Down, United Kingdom
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Aminzadeh A, Larsen CE, Boesen T, Jørgensen R. High-resolution structure of native toxin A from Clostridioides difficile. EMBO Rep 2022; 23:e53597. [PMID: 34817920 PMCID: PMC8728606 DOI: 10.15252/embr.202153597] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2021] [Revised: 11/09/2021] [Accepted: 11/10/2021] [Indexed: 01/07/2023] Open
Abstract
Clostridioides difficile infections have emerged as the leading cause of healthcare-associated infectious diarrhea. Disease symptoms are mainly caused by the virulence factors, TcdA and TcdB, which are large homologous multidomain proteins. Here, we report a 2.8 Å resolution cryo-EM structure of native TcdA, unveiling its conformation at neutral pH. The structure uncovers the dynamic movement of the CROPs domain which is induced in response to environmental acidification. Furthermore, the structure reveals detailed information about the interaction area between the CROPs domain and the tip of the delivery and receptor-binding domain, which likely serves to shield the C-terminal part of the hydrophobic pore-forming region from solvent exposure. Similarly, extensive interactions between the globular subdomain and the N-terminal part of the pore-forming region suggest that the globular subdomain shields the upper part of the pore-forming region from exposure to the surrounding solvent. Hence, the TcdA structure provides insights into the mechanism of preventing premature unfolding of the pore-forming region at neutral pH, as well as the pH-induced inter-domain dynamics.
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Affiliation(s)
- Aria Aminzadeh
- Department of Bacteria, Parasites and FungiStatens Serum InstitutCopenhagenDenmark
| | - Christian Engelbrecht Larsen
- Interdisciplinary Nanoscience Center (iNANO)Aarhus UniversityAarhusDenmark
- Department of Molecular Biology and GeneticsAarhus UniversityAarhusDenmark
| | - Thomas Boesen
- Interdisciplinary Nanoscience Center (iNANO)Aarhus UniversityAarhusDenmark
- Department of Molecular Biology and GeneticsAarhus UniversityAarhusDenmark
| | - René Jørgensen
- Department of Bacteria, Parasites and FungiStatens Serum InstitutCopenhagenDenmark
- Department of Science and EnvironmentUniversity of RoskildeRoskildeDenmark
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37
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Liu Z, Zhang S, Chen P, Tian S, Zeng J, Perry K, Dong M, Jin R. Structural basis for selective modification of Rho and Ras GTPases by Clostridioides difficile toxin B. Sci Adv 2021; 7:eabi4582. [PMID: 34678063 PMCID: PMC8535798 DOI: 10.1126/sciadv.abi4582] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/11/2021] [Accepted: 09/02/2021] [Indexed: 05/15/2023]
Abstract
Toxin B (TcdB) is a primary cause of Clostridioides difficile infection (CDI). This toxin acts by glucosylating small GTPases in the Rho/Ras families, but the structural basis for TcdB recognition and selectivity of specific GTPase substrates remain unsolved. Here, we report the cocrystal structures of the glucosyltransferase domain (GTD) of two distinct TcdB variants in complex with human Cdc42 and R-Ras, respectively. These structures reveal a common structural mechanism by which TcdB recognizes Rho and R-Ras. Furthermore, we find selective clustering of adaptive residue changes in GTDs that determine their substrate preferences, which helps partition all known TcdB variants into two groups that display distinct specificities toward Rho or R-Ras. Mutations that selectively disrupt GTPases binding reduce the glucosyltransferase activity of the GTD and the toxicity of TcdB holotoxin. These findings establish the structural basis for TcdB recognition of small GTPases and reveal strategies for therapeutic interventions for CDI.
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Affiliation(s)
- Zheng Liu
- Department of Physiology and Biophysics, University of California, Irvine, Irvine, CA 92697, USA
| | - Sicai Zhang
- Department of Urology, Boston Children’s Hospital, and Departments of Microbiology and Surgery, Harvard Medical School, Boston, MA 02115, USA
| | - Peng Chen
- Department of Physiology and Biophysics, University of California, Irvine, Irvine, CA 92697, USA
| | - Songhai Tian
- Department of Urology, Boston Children’s Hospital, and Departments of Microbiology and Surgery, Harvard Medical School, Boston, MA 02115, USA
| | - Ji Zeng
- Department of Urology, Boston Children’s Hospital, and Departments of Microbiology and Surgery, Harvard Medical School, Boston, MA 02115, USA
| | - Kay Perry
- NE-CAT and Department of Chemistry and Chemical Biology, Cornell University, Argonne National Laboratory, Lemont, IL 60439, USA
| | - Min Dong
- Department of Urology, Boston Children’s Hospital, and Departments of Microbiology and Surgery, Harvard Medical School, Boston, MA 02115, USA
| | - Rongsheng Jin
- Department of Physiology and Biophysics, University of California, Irvine, Irvine, CA 92697, USA
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