CONTROL OF BACTERIAL TOXINS BY VIRUSES AND PLASMIDS

通过病毒和质粒控制细菌毒素

• 批准号: 3444468
• 负责人: Randall K Holmes
• 金额: $ 7.36万
• 依托单位: U.S.UNIFORMED SERVICES UNIV HLTH SCIS
• 依托单位国家: 美国
• 财政年份: 1976
• 资助国家: 美国
• 起止时间: 1976-09-30 至 1990-01-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/3444468
• 关键词: Corynebacterium diphtheriae; Escherichia coli; Vibrio cholerae; antiserum; bacterial genetics; bacterial toxins; bacterial virus; biological models; chemical structure function; cholera toxin; cholera vaccine; communicable disease control; diphtheria toxin; enterotoxins; genetic manipulation; genetic regulation; genetic transcription; genetic translation; immunity; immunochemistry; molecular cloning; monoclonal antibody; plasmids; radioimmunoassay; structural genes; virus antigen; virus genetics

Viruses and plasmids control the production of several bacterial toxins. The heat-labile enterotoxin (LT) of Escherichia coli, a recently discovered LT-like toxin of E. coli, and diphtheria toxin (DT), the classical exotoxin of Corynebacterium diphtheriae, will be studied in this project. LT is directly involved in the pathogenesis of diarrhea in humans and animals; it is a model for control of toxinogenesis by plasmids. DT is directly involved in the pathogenesis of diphtheria and is a model for control of toxinogenesis by bacteriophages. In contrast, the role of LT-like toxin in disease has not yet been investigated. The long range goals of the proposed studies are to characterize these toxins and the molecular mechanisms that control their production and to apply this knowledge for control of infectious diseases in humans. A wide variety of biochemical, immunologic, genetic, and recombinant DNA methods will be used. The specific aims for studying LT are to define the structure of specific antigenic determinants (epitopes) by using monoclonal anti-LT antibodies and synthetic oligopeptides related to LT and characterize mechanisms that regulate synthesis, processing and secretion of LT in E. coli. The specific aims of the proposed studies of LT-like toxin are to purify the toxin, characterize its immunochemical properties and mode of action, clone and characterize the toxin structural gene(s), analyze the regulation of toxinogenesis, and determine the role of the toxin in pathogenesis of diarrheal diseases. The studies of LT and LT-like toxin will provide information that should be relevant for the design of synthetic oligopeptide vaccines and/or the construction of bacterial strains for use as living attenuated vaccines to protect against diarrheal diseases caused by E. coli. The specific aims for studying DT are to characterize its interactions with artificial membrane vesicles and analyze the molecular basis for the role of iron in regulating toxinogenesis in C. diphtheriae. The studies with model membranes may shed light on the mechanism of translocation of DT across biological membranes. The studies on the role of iron will provide fundamental knowledge about regulation of toxinogenesis in C. diphtheriae. This knowledge may have practicalapplications for production of DT and related mutant proteins (CRMs) to be used for the preparation of conjugated vaccines or immunotoxins

病毒和质粒控制几种细菌毒素的产生。 大肠杆菌的热量肠毒素（LT），最近发现的 大肠杆菌的LT样毒素和白喉毒素（DT），经典的外毒素 该项目将研究Corynebacterium diphtheriae。 Lt是 直接参与人类和动物腹泻的发病机理；它 是控制质粒毒素发生的模型。 DT是直接的 参与白喉发病机理，是控制的模型 噬菌体的毒素发生。 相反，LT样毒素在 尚未研究疾病。 远程目标 拟议的研究是为了表征这些毒素和分子 控制其生产并将这些知识应用于 控制人类传染病。 多种生化， 将使用免疫，遗传和重组DNA方法。 这 研究LT的具体目的是定义特定的结构 通过使用单克隆抗LT抗体的抗原决定因素（表位） 和与LT相关的合成寡肽，并表征了机制 调节大肠杆菌中LT的合成，加工和分泌。 这 LT样毒素的拟议研究的具体目的是净化 毒素，特征其免疫化学特性和作用方式，克隆 并表征毒素结构基因，分析调节 毒素发生，并确定毒素在发病机理中的作用 腹泻疾病。 LT和LT样毒素的研究将提供 应该与合成设计有关的信息 寡肽疫苗和/或构建细菌菌株供使用 当生物减弱疫苗以防止腹泻疾病引起的疫苗 大肠杆菌。 研究DT的具体目的是表征其 与人造膜囊泡相互作用并分析分子 铁在调节白喉梭菌中调节毒素发生中的作用的基础。 使用模型膜的研究可能会阐明 DT跨生物膜的易位。 关于角色的研究 铁将提供有关调节的基本知识 白喉梭菌中的毒素发生。 这些知识可能有 生产DT和相关突变蛋白的实用应用 （CRMS）用于制备共轭疫苗或免疫毒素