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，其特征是间歇性气道阻塞和高反应性，有时 并伴有气道重塑。尽管哮喘的根本原因仍知之甚少，但其中之一 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（肺炎支原体）感染在抗生素治疗后显示肺功能有所改善 治疗，而检测呈阴性的患者则不接受治疗，这表明肺炎支原体之间存在因果关系 感染和哮喘症状的严重程度。尽管肺炎支原体与肺炎支原体之间存在很强的临床相关性。 感染和哮喘病例的子集，直到最近，才确定了可能发挥作用的毒力因子 疾病的发病机制仍然难以捉摸。然而，当我们发现 591 个氨基酸时，这种情况发生了变化。 社区获得性肺炎支原体中具有 ADP-核糖基转移酶 (ART) 活性的酸性蛋白 呼吸窘迫综合征毒素 (CARDS TX)。本提案中概述的实验旨在 使用一系列生物物理技术揭示 CARDS TX 的结构和作用。使用成熟的 利用单晶X射线衍射工具，我们将确定：1）CARDS TX的三维结构； 2） CARDS TX 与其 NAD"" 辅因子复合； 3) CARDS TX 与中和单克隆抗体 Fab 复合 碎片； 4) CARDS TX与其细胞表面受体的重组胞外结构域形成复合物 表面活性蛋白-A (SP-A)。长期目标是将这些 3D 结构与信息结合使用 来自项目 1 和 2 作为 CARDS TX 抑制剂设计的平台，这可能代表新颖 用于治疗哮喘和肺部炎症的治疗剂。