Neisseria gonorrhoeae central metabolism in the context of neutrophilic inflammation

摘要 淋病奈瑟氏菌（Gc）是性传播疾病淋病的病原体。Gc为 对人类健康的突出威胁，因为出现了对所有现有药物都有抗性的“超级细菌”菌株， 抗生素及其临床后遗症，包括不孕症和慢性盆腔疼痛，具有严重和终身 方面的影响. GC是高度适应殖民人类粘膜表面，在那里它生存，尽管启动了强大的 炎症反应和多形核白细胞（PMN或中性粒细胞）的流入， 细菌我们最近使用了无偏见的，全基因组的转座子测序和双RNA方法， Gc和PMN的测序以鉴定有助于成功Gc感染PMN的一组基因。GC 代谢基因在该队列中的代表性过高，表明Gc利用不同的代谢途径， 绕过人体粘膜防御系统我们已经将这些信息应用于系统生物学方法， 生成Gc的初步代谢网络重建。这一分析导致预测，Gc 利用特定的宿主衍生代谢物来促进其代谢-特别是乳酸。中性粒细胞是高度糖酵解的 从而分泌乳酸。乳酸可以被Gc消耗，并且已知其刺激Gc糖酵解。因此 我们假设Gc利用PMN代谢，特别是乳酸分泌，在粘膜表面存活。 在这个提议中，我们将确定在中性粒细胞存在下Gc使用的中心碳代谢途径， 使用代谢物分析、代谢建模和Gc代谢中的细菌基因敲除的组合 内切酶然后，我们将测试这些代谢途径在GC中增强细菌存活的必要性。 中性粒细胞和潜在的机制，包括调节中性粒细胞抗菌反应，改变 对中性粒细胞抗菌成分敏感，和/或规避宿主营养免疫，或 调节嗜中性粒细胞抗微生物应答。总之，这一建议将解决知识方面的主要差距， 感染期间Gc的基本代谢过程可能对结果产生重大影响 淋病

ABSTRACT Neisseria gonorrhoeae (Gc) is the causative agent of the sexually transmitted disease gonorrhea. Gc is a prominent threat to human health due to emergence of “superbug” strains that are resistant to all current antibiotics and its clinical sequelae, including infertility and chronic pelvic pain, that have severe and lifelong effects. Gc is highly adapted to colonize human mucosal surfaces, where it survives despite initiating a robust inflammatory response and influx of polymorphonuclear leukocytes (PMNs or neutrophils) that typically clear bacteria. We recently used the unbiased, genome-wide approaches of transposon-sequencing and dual RNA- sequencing of Gc and PMNs to identify a cohort of genes contributing to successful Gc infection of PMNs. Gc metabolic genes were overrepresented in this cohort, suggesting that Gc utilizes distinct metabolic pathways to circumvent human mucosal defenses. We have applied this information to systems biology approaches to generate a preliminary metabolic network reconstruction for Gc. This analysis leads to the prediction that Gc utilizes specific host-derived metabolites to fuel its metabolism – in particular, lactate. PMNs are highly glycolytic and consequently secrete lactate. Lactate can be consumed by Gc and is known to stimulate Gc glycolysis. Thus we hypothesize that Gc exploits PMN metabolism, specifically lactate secretion, to survive at mucosal surfaces. In this proposal, we will identify the central carbon metabolic pathways used by Gc in the presence of neutrophils, using a combination of metabolite analysis, metabolic modeling, and bacterial genetic knockouts in Gc metabolic enzymes. We will then test the necessity of these metabolic pathways in Gc for enhancing bacterial survival from neutrophils and the underlying mechanisms, including modulating neutrophil antimicrobial responses, changing Gc sensitivity to neutrophil antimicrobial components, and/or circumventing host nutritional immunity, or modulating neutrophil antimicrobial responses. Together, this proposal will address key gaps in knowledge of the fundamental metabolic processes of Gc during infection that are likely to have major impacts on outcomes of gonorrhea.