Structure-based targeting of the C. difficile toxin (CDT) from hypervirulent bacterial strains

基于结构的高毒力细菌菌株中艰难梭菌毒素 (CDT) 的靶向

• 批准号: 10455150
• 负责人: David Joseph Weber
• 金额: $ 52.18万
• 依托单位: UNIVERSITY OF MARYLAND BALTIMORE
• 依托单位国家: 美国
• 财政年份: 2021
• 资助国家: 美国
• 起止时间: 2021-08-06 至 2023-07-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/10455150
• 关键词: 3-Dimensional; Address; Adenosine Diphosphate Ribose; Amino Acids; Anisotropy; Antibiotics; Area; Bacteria; Bacterial Infections; Binding; Biological Assay; CD44 gene; Cells; Chemicals; Classification; Clostridium difficile; Colonoscopy; Complex; Computer software; Corynebacterium diphtheriae; Cryoelectron Microscopy; Cytoplasm; Dangerousness; Data; Data Analyses; Detection; Development; Diarrhea; Diphtheria Toxin; Enterotoxins; Enzymes; Future; G Actin; Generations; Goals; Gold; Healthcare; Infection; Journals; Laboratories; Length; Measures; Medical; Membrane; Methods; Modeling; Modification; Molecular; Mutation; Peer Review; Pharmaceutical Preparations; Physiological; Preparation; Process; Proteins; Pseudomonas aeruginosa; Publications; Receptor Cell; Recurrence; Reporting; Research; Resolution; Roentgen Rays; Site; Site-Directed Mutagenesis; Structure; System; Targeted Toxins; Therapeutic; Toxic effect; Toxin; Validation; Work; X-Ray Crystallography; base; biophysical properties; cytolethal distending toxin; cytotoxic; density; drug development; drug discovery; experimental study; fecal transplantation; instrumentation; interest; mutant; programs; protein structure; public health priorities; receptor; receptor binding; response; structural biology; therapeutic target; treatment strategy

Abstract – Targeting Clostridium difficile infection (CDI) is challenging because treatments are limited to a small number of antibiotics, colonoscopy, and experimental methods (i.e. fecal transplant), and there are unacceptably high recurrence rates, particularly with hypervirulent strains such as NAP1/P1/027. One serious problem with hypervirulent strains is that they have a binary toxin termed the C. difficile toxin (CDT), in addition to the enterotoxins TsdA and TsdB. The CDT binary toxin has an enzymatic component, termed CDTa, and a pore-forming or delivery subunit termed CDTb. The cytotoxic response to host cells is the result of a catalytic transfer of the ADP-ribose moiety of NAD to host G-actin, its physiological substrate, via CDTa. Delivery of CDTa to the cytoplasm is via the pore-forming component of the binary toxin, CDTb. While treatment options exist for TcdA/TcdB, there is no therapy to target CDT and the mechanism of action for the CDTa/CDTb binary toxin associated with the hypervirulent strains of CDI is not well understood. In our labs, a structural biology approach is underway via cryoEM to characterize the CDTa/CDTb binary complex using active and fully processed full-length constructs of both CDTa and CDTb (Aim 1). This will be followed by more detailed structural and dynamic studies involving specific domains of the binary toxins using NMR and X-ray crystallography (Aim 1). In Aim 2, studies of complexes relevant to host cell engagement are planned to include those of CDTb and the CDTa/CDTb complex in membrane-like media and bound to constructs derived from host cell receptors (i.e. CD44, LSR). Together the structures will be used to define regions on CDT important for engaging the host cell and provide information necessary to block this process, as a therapeutic approach. Because other infectious bacteria make use of similar “Type III” systems for delivering ADP- ribosylating toxins (i.e. Corynebacterium diphtheriae, diphtheria toxin, Pseudomonas aeruginosa, and others), it is anticipated that the research completed here for CDI could benefit treatment strategies for hypervirulent C. difficile as well as for other dangerous bacterial infections.

针对艰难梭菌感染（CDI）是具有挑战性的，因为治疗仅限于a

项目成果

The Importance of Therapeutically Targeting the Binary Toxin from Clostridioides difficile.

• DOI: 10.3390/ijms22062926
• 发表时间: 2021-03-13
• 期刊: International journal of molecular sciences
• 影响因子: 5.6
• 作者: Abeyawardhane DL;Godoy-Ruiz R;Adipietro KA;Varney KM;Rustandi RR;Pozharski E;Weber DJ
• 通讯作者: Weber DJ

Computer-Aided Drug Design: An Update.

• DOI: 10.1007/978-1-0716-2855-3_7
• 发表时间: 2023
• 期刊: Methods in molecular biology
• 作者: Wenbo Yu;David J. Weber;Alexander D. MacKerell