Acquisition of gonococcal denitrification apparatus in the Neisseria meningitidis urethritis clade

项目摘要 脑膜炎奈瑟菌在鼻咽部无症状地携带，高达5%-10%的人口携带脑膜炎奈瑟菌。 并且仍然是脑膜炎和迅速致命的败血症的主要原因，通常在其他健康的人中。 从历史上看，脑膜炎奈瑟氏菌并不是一个重要的性传播病原体。然而，自2015年以来， 最近爆发的性传播脑膜炎球菌性尿道炎主要发生在异性恋人群中。 美国13个州、英国和越南的男性。与以往零星的脑膜炎双球菌病例不同 尿道炎，这些尿道炎病例都是由一种被膜缺陷的脑膜炎球菌分支引起的，属于 超侵袭性cc11.2血统。这种脑膜炎奈瑟菌分支，就像淋病奈瑟菌一样，会导致男性尿道炎。 在社区中史无前例的数量，也可以从咽部和直肠分离，并可引起 脑膜炎双球菌血症和脑膜炎，以及其他粘膜感染(新生儿结膜炎)。而孤立的 报告了由一系列脑膜炎双球菌基因引起的泌尿生殖道定植和尿道炎病例，无 其他基因导致了广泛的尿道炎暴发。这些尿道炎的爆发表明11.2 世系支系获得了新的遗传和表型变化，使其能够有效地在 泌尿生殖道，以适应局部的先天免疫反应，并引起泌尿生殖道疾病。为了支持…… 在这一假设下，我们发现所有脑膜炎奈瑟氏菌尿道炎分离株都来自多个州和 全球范围内，但不是散发性脑膜炎球菌尿道炎分离株具有明显的淋球菌反硝化作用 淋球菌亚硝酸盐还原酶ANIA和淋球菌一氧化氮(NO)还原酶Norb。这 精确的染色体基因转换事件也赋予了该支系淋球菌调节区 这将编码Ania和Norb的不同转录本分开。这种Ania-Norb转换似乎提供了 对脑膜炎奈瑟氏菌的主要适应是对氧气受限的微需氧/厌氧泌尿生殖环境和 使得这种嗜尿性脑膜炎双球菌的出现。在两个具体目标中，我们试图定义独特的 通过淋球菌Ania-Norb基因赋予该脑膜炎球菌分支的调节和生理特性 转换事件。在目标1中，独特的混合转录调控网络，由多个 控制不同转录的淋球菌Ania和Norb启动子的脑膜炎球菌调节剂，将是 详细审查以定义这一分支中的新的和关键的顺式和跨式监管要素。全球转录 将使用RNA-seq检查受分支中的基因转换影响的图谱。在目标2中，我们将确定 淋球菌反硝化转换对在泌尿生殖系统发病中重要的表型的影响： 微氧生长，NO敏感性和利用，以及对NO介导的免疫反应的防御。 这些拟议研究的成功完成将为我们提供宝贵的洞察力，让我们了解 并解决NIAID的两个关键优先领域，即新发感染和性传播感染。

Project Summary Neisseria meningitidis is carried in the nasopharynx asymptomatically by up to 5-10% of the human population and remains a leading cause of meningitis and rapidly fatal sepsis, usually in otherwise healthy individuals. Historically, N. meningitidis has not been a significant sexually transmitted pathogen. However, since 2015 recent outbreaks of sexually transmitted meningococcal urethritis have occurred, primarily, in heterosexual males in over thirteen US states, the UK, and Vietnam. Unlike previous sporadic cases of meningococcal urethritis, these urethritis cases are all caused by a capsule-defective meningococcal clade belonging to the hyper-invasive cc11.2 lineage. This clade of N. meningitidis, like N. gonorrhoeae, causes male urethritis in unprecedented numbers in communities, can also be isolated from the pharynx and rectal tract, and can cause meningococcemia and meningitis, as well as other mucosal infections (neonatal conjunctivitis). Whereas isolated cases of urogenital colonization and urethritis caused by a range of meningococcal genotypes are reported, no other genotype has caused widespread urethritis outbreaks. These urethritis outbreaks suggest that this 11.2 lineage clade has acquired novel genetic and, thus, phenotypic changes that allow it to effectively colonize the urogenital tract, to adapt to local innate immune responses, and to cause urogenital tract disease. In support of this hypothesis, we discovered that all isolates of N. meningitidis urethritis clade, from multiple states and globally, but not sporadic meningococcal urethritis isolates, have the distinct N. gonorrhoeae denitrification apparatus - the gonococcal nitrite reductase, AniA, and the gonococcal nitric oxide (NO) reductase, NorB. This precise chromosomal gene conversion event has also endowed the clade with the gonococcal regulatory region that separates the divergent transcripts encoding aniA and norB. This aniA-norB conversion appears to provide a major adaptation to N. meningitidis for the oxygen-limited microaerobic/anaerobic urogenital environment and allowing emergence of this urethrotropic meningococcal clade. In two Specific Aims, we seek to define the unique regulatory and physiological traits conferred to this meningococcal clade through the gonococcal aniA-norB gene conversion event. In Aim 1, the unique hybrid transcriptional regulatory network, consisting of multiple meningococcal regulators controlling the divergently transcribed gonococcal aniA and norB promoters, will be examined in detail to define, new and critical, cis and trans regulatory elements in this clade. Global transcription profiles affected by the gene conversion in the clade will be examined using RNA-seq. In Aim 2, we will determine the impact of the gonococcal denitrification conversion on phenotypes important in urogenital pathogenesis: microaerobic growth, NO susceptibility and utilization, and defense against NO-mediated immune responses. Successful completion of these proposed studies will provide valuable insights into the continuing evolution of urethrotropic N. meningitidis and address two NIAID key priority areas, emerging infections and STIs.