Adaptation to anaerobiosis in H influenzae pathogenesis

流感嗜血杆菌发病机制中对厌氧的适应

• 批准号: 6487369
• 负责人: RYAN E TYLER
• 金额: $ 0.84万
• 依托单位: UNIVERSITY OF MICHIGAN AT ANN ARBOR
• 依托单位国家: 美国
• 财政年份: 2002
• 资助国家: 美国
• 起止时间: 2002-05-01 至
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/6487369
• 关键词: Escherichia coli; Haemophilus influenzae; anaerobiosis; bacteria infection mechanism; bacterial genetics; biological signal transduction; environmental adaptation; gene expression; green fluorescent proteins; host organism interaction; hypoxia; laboratory rat; nitrate reductases; nitrites; oxidation reduction reaction; pathologic process; polymerase chain reaction; predoctoral investigator

DESCRIPTION (provided by applicant): Haemophilus influenzae is a common asymptomatic colonizer of the upper respiratory tract, yet also causes a range of invasive diseases such as otitis media, a middle ear infection that produces acute pain, distress and temporary or permanent hearing loss in children. The presence of obligate anaerobic species with H. influenzae in the middle ear fluid and the nasopharynx of otitis media patients indicates that H. influenzae encounters low oxygen conditions in vivo. H. influenzae possesses redox-responsive systems found in several other bacterial pathogens. The participation of these redox-responsive systems in altering global gene expression in response to oxygen deprivation will be investigated by characterizing the expression profiles of the nitrate and nitrite reductases. Preliminary data indicate that nitrate and nitrite reductase expression in H. influenzae is mediated by environmental signals, such as substrate availability and environmental oxygen levels. Additionally, the in vitro characterization of the nitrate and nitrite reductase expression profiles permits the development of the reductase-encoding genes as reporters for the physiological state of H. influenzae during infant rat infection. Therefore, the importance of this study is to not only yield insight into the regulatory processes of redox sensing in H. influenzae, but also to characterize the physiological state of this bacterium within host niches.

性状（由申请方提供）：流感嗜血杆菌是常见的 上呼吸道无症状定植者，但也会引起一系列 中耳炎是一种中耳感染， 儿童急性疼痛、痛苦和暂时或永久性听力损失。的 存在专性厌氧物种与H.中耳流行性感冒 中耳炎患者的鼻咽部和脑脊液中的H.流感 在体内遇到低氧条件。H.流感病毒具有 在其他几种细菌病原体中发现的氧化还原反应系统。的 这些氧化还原反应系统参与改变全局基因 将通过以下方法研究对缺氧反应的表达 表征硝酸盐还原酶和亚硝酸盐还原酶的表达谱。 初步数据表明，硝酸盐和亚硝酸盐还原酶在H。 流感是由环境信号介导的，如底物的可用性 和环境中的氧气含量此外，体外表征的 硝酸盐和亚硝酸盐还原酶表达谱允许 还原酶编码基因作为H. 在幼鼠感染期间感染流感病毒。因此，本研究的重要性 不仅是为了深入了解氧化还原传感的调节过程， H.流感，而且还表征这种生理状态 宿主壁龛内的细菌。