PSEUDOMONAS IN CYSTIC FIBROSIS--REGULATION OF MUCOIDY

囊性纤维化中的假单胞菌——粘液的调节

• 批准号: 2003672
• 负责人: VOJO P DERETIC
• 金额: $ 29.45万
• 依托单位: UNIVERSITY OF MICHIGAN AT ANN ARBOR
• 依托单位国家: 美国
• 财政年份: 1992
• 资助国家: 美国
• 起止时间: 1992-02-01 至 2002-01-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/2003672
• 关键词: Pseudomonas aeruginosa; alginates; bacterial cytopathogenic effect; bacterial proteins; clinical research; cystic fibrosis; gel electrophoresis; genetic promoter element; genetic regulation; genetic regulatory element; genetic transcription; genetically modified animals; green fluorescent proteins; human subject; laboratory mouse; molecular pathology; mucus; oxidative stress; protein biosynthesis; protein purification; proteoglycan; respiratory infections; site directed mutagenesis; virulence

Pseudomonas aeruginosa conversion to mucoid phenotype plays a critical role in the establishment of chronic respiratory infections in cystic fibrosis (CF) which are responsible for the high morbidity and mortality in this disease. Conversion to mucoidy is controlled by the algU mucABCD locus. The algU gene is a positive regulator of mucoidy and encodes an equivalent of the extreme that shock sigma factor RpoE from enteric bacteria. This strongly suggests a connection between the extreme stress response and conversion of P. aeruginosa to mucoidy. The goal is of this proposal are: i) to delineate the molecular mechanism of conversion to mucoidy in P. aeruginosa; ii) to investigate the role of the stress system that controls mucoidy and possibly additional aspects of P. aeruginosa virulence; and iii) to assess the contributions of mucoidy and co-regulated systems to the pathogenic processes during chronic respiratory infections in CF. The following studies will be carried out: i) AlgU-dependent transcription of the critical biosynthetic and regulatory genes necessary for the production of and oxidative stress response will be established; ii) MucA (or MucB) activity as an anti-IgMa factor or inhibitor of AlgU activity will be investigated and additional mutations and genes causing conversion to mucoidy will be characterized; iii) the proteins and genes that are controlled by AlgU and induced by stress or overexpressed in muc mutants will be analyzed by metabolic labeling, 2D gel analysis, and expression technology based on green fluorescent protein; iv) the role of AlgU-dependent systems in P. aeruginosa pathogenesis in acute and chronic infections will be investigated by: (a) comparing the isogeneic algU+ and algU null strains for their susceptibility to killing with reactive oxygen intermediates and by phagocytic cells; (b) determining virulence of isogeneic exposed to P. aeruginosa aerosols; and (c) analyzing AlgU-dependent immunoreactive proteins using sera from CF patients. These studies will provide a complete model of the molecular mechanisms which govern conversion to mucoidy and develop a comprehensive view of the role that the extreme stress sigma factor AlgU plays in P. aeruginosa virulence and pathogenesis in CF with implications for pharmacological or immunological intervention.

铜绿假单胞菌转化为粘液表型发挥 在建立慢性呼吸道中的关键作用 囊性纤维化（CF）的感染负责 这种疾病的高发病和死亡率。 转换为 粘液受到Algu粘液胶质基因座的控制。 algu基因是 粘液的阳性调节剂，并编码相当于 极端的肠细菌的冲击sigma因子rpoE。 这 强烈建议极端压力响应之间有联系 和铜绿假单胞菌转化为粘液菌。 目标是 建议是：i）描述转换的分子机制 在铜绿假单胞菌中进行粘液； ii）调查 控制粘液和可能其他方面的压力系统 铜绿假单胞菌毒力； iii）评估 粘液和共同调节的系统到致病过程 CF中的慢性呼吸道感染。 以下研究将 进行：i）临界的algu依赖性转录 生物合成和调节基因生产所需的基因 将建立氧化应激反应； ii）粘液（或 MUCB）活性作为抗污染因子或Algu活性的抑制剂 将研究并引起其他突变和基因 转化为粘液菌的表征； iii）蛋白质和 由Algu控制并由应力或应力诱导的基因 在MUC突变体中过表达将通过代谢分析 基于绿色的标签，2D凝胶分析和表达技术 荧光蛋白； iv）Algu依赖性系统在P中的作用。 急性和慢性感染中的铜绿疾病发病机理将是 调查者：（a）比较均匀的algu+和algu null 用反应性氧气杀死的菌株 中间体和吞噬细胞； （b）确定的毒力 暴露于铜绿假单胞菌气溶胶的异质化； （c）分析 使用CF患者的血清依赖ALGU依赖性免疫反应性蛋白。 这些研究将提供分子的完整模型 控制转化为粘液的机制并发展 对极端压力西格玛因子的作用的全面看法 Algu在铜绿假单胞菌的毒力和发病机理中发挥了CF 对药理或免疫学干预的影响。