Structure and action of CARDS toxin

卡毒素的结构和作用

• 批准号: 8182002
• 负责人: Peter JOHN HART
• 金额: $ 31.66万
• 依托单位: UNIVERSITY OF TEXAS HLTH SCIENCE CENTER
• 依托单位国家: 美国
• 财政年份: 2011
• 资助国家: 美国
• 起止时间: 2011-07-01 至 2016-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8182002
• 关键词: 3-Dimensional; ADP Ribose Transferases; Acute; Allergic inflammation; Amino Acid Sequence; Amino Acids; Antibiotic Therapy; Asthma; Biochemical; Blood Vessels; Bordetella pertussis; C-terminal; Catalytic Domain; Cell Surface Receptors; Chest; Chronic; Clinical; Collaborations; Community Acquired Respiratory Distress Syndrome Toxin; Complex; Diagnostic; Disease; Etiology; Exotoxins; Exposure to; Extracellular Domain; Fab Immunoglobulins; Goals; Human; Inflammation; Inflammatory; Lung; Lung diseases; Lymphocyte; Mediating; Molecular Structure; Mus; Mycoplasma pneumonia infection; Mycoplasma pneumoniae; Papio; Pathogenesis; Pathology; Patients; Peptide Sequence Determination; Pertussis; Play; Pneumonia; Progress Reports; Proteins; Pulmonary Surfactant-Associated Protein A; Recombinants; Reporting; Research; Resolution; Respiratory System; Respiratory tract structure; Role; Severities; Structure; Symptoms; Techniques; Testing; Therapeutic Agents; Time; Toxin; Virulence; Virulence Factors; Work; X ray diffraction analysis; X-Ray Diffraction; airway obstruction; airway remodeling; cofactor; design; inhibitor/antagonist; neutralizing monoclonal antibodies; novel diagnostics; novel therapeutics; pathogen; pulmonary function; receptor binding; research study; respiratory; small molecule; three dimensional structure; tool

Asthma is a complex disorder characterized by episodic airway obstruction and hyper-responsiveness, sometimes accompanied by airway remodeling. Although the underlying causes of asthma remain poorly understood, one contributing factor is exposure to respiratory pathogens. For example, asthmatics positive for Mycoplasma pneumoniae (M. pneumoniae) infection have demonstrated an improvement in pulmonary function after antibiotic treatment whereas patients that test negative do not, suggesting a causal relationship between M. pneumoniae infection and asthma symptom severity. Although there is a strong clinical correlation between M. pneumoniae infection and a sub-set of asthma cases, until recently, the identification of a virulence factor that might play a role in disease pathogenesis had remained elusive. This situation changed, however, when we discovered a 591 amino acid protein with ADP-ribosyltransferase (ART) activity in M. pneumoniae designated Community Acquired Respiratory Distress Syndrome ToXin (CARDS TX). The experiments outlined in this proposal are designed to uncover the structure and action of CARDS TX using a range of biophysical techniques. Using the well-established tools of single crystal X-ray diffraction, we will determine: 1) the three-dimensional structure of CARDS TX; 2) CARDS TX in complex with its NAD"" co-factor; 3) CARDS TX in complex with neutralizing monoclonal antibody Fab fragments; and 4) CARDS TX in complex with recombinant extracellular domains of its cell surface receptor surfactant protein-A (SP-A). A longer term goal is to use these 3-D structures in conjunction with the information coming from Projects 1 and 2 as platforms for the design of CARDS TX inhibitors, which may represent novel therapeutic agents for the treatment of asthma and pulmonary inflammation.

哮喘是一种复杂的疾病，其特征是发作性气道阻塞和高反应性，有时 并伴有气道重塑虽然哮喘的根本原因仍然知之甚少， 影响因素是接触呼吸道病原体。例如，支原体阳性的哮喘患者 肺炎支原体（M.肺炎）感染的患者在抗生素治疗后肺功能得到改善 治疗，而测试阴性的患者没有，这表明M.肺炎 感染和哮喘症状严重程度。虽然M.肺炎 感染和哮喘病例的子集，直到最近，鉴定出可能起作用的毒力因子， 疾病的发病机制仍然是难以捉摸的。然而，当我们发现一个591氨基酸时， 具有ADP-核糖基转移酶（ART）活性的酸性蛋白。指定为社区获得性肺炎 呼吸窘迫综合征ToXin（TOXin）。本提案中概述的实验旨在 使用一系列生物物理学技术来揭示BMPTX的结构和作用。使用完善的 单晶X射线衍射的工具，我们将确定：1）的三维结构的X-TX; 2） 3）与中和性单克隆抗体Fab复合的BTX 片段;和4）与其细胞表面受体的重组胞外结构域复合的BTX 表面活性蛋白-A（SP-A）。一个长期的目标是将这些三维结构与信息结合起来使用 来自项目1和2，作为用于设计NATTX抑制剂的平台，其可以代表新的 用于治疗哮喘和肺部炎症的治疗剂。