Quorum Sensing in the Commensal Bacterium Bacteroides fragilis

脆弱拟杆菌的群体感应 肠上皮细胞在哺乳动物宿主和大量微生物伴侣之间提供了至关重要的界面（400 m[2]）。然而，人们对调节我们与肠道细菌有益关系的机制知之甚少。在一个称为群体感应的过程中，细菌使用称为自诱导物的化学信号分子进行交流。群体感应允许细菌同步集体行为，如多糖分泌和生物膜形成，这是哺乳动物肠道环境中肠道细菌部署的标志性特征。事实上，细菌和哺乳动物的肠道细胞是在不断接触彼此，结合在原核生物和真核生物中的细胞间通信的普遍使用，使我推测，细菌和/或大肠杆菌分泌的信号参与通过内部和王国间的通信维持稳态。我将通过研究脆弱拟杆菌与真核细胞的相互作用来研究这些想法。B。脆弱菌是正常肠道微生物群落的重要成员，其通过指导宿主抗炎反应在维持肠道健康中起重要作用。然而，这些相互作用的机制尚不清楚。本研究的目的是探讨肠道常驻菌群如何通过群体感应行为影响肠道健康，并对影响B群体行为的群体感应因子进行表征。fragilis，并确定宿主免疫系统如何控制B。脆弱菌群体感应

Quorum sensing in the commensal bacterium Bacteroides fragilis Intestinal epithelial cells provide the crucial interface (400 m[2]) between mammalian hosts and a vast consortium of microbial partners. Yet, little is known about the mechanisms regulating our beneficial relations with commensal bacteria. In a process called quorum sensing, bacteria communicate using chemical signal molecules called autoinducers. Quorum sensing allows bacteria to synchronize collective behaviors such as polysaccharide secretion and biofilm formation, hallmark traits deployed by commensal bacteria in the mammalian gut environment. The fact that bacteria and mammalian intestinal cells are in constant contact with one another, combined with the universal use of intercellular communication in prokaryotes and eukaryotes, has led me to speculate that bacteria- and/or mammalian-secreted signals are involved in maintaining homeostasis via intra- and inter-kingdom communication. I will investigate these ideas by studying Bacteroides fragilis-eukaryotic cell interactions. B. fragilis is a prominent member of the normal gut microflora that plays a vital role in maintaining intestinal health by directing host anti-inflammatory responses. However, the mechanisms underlying these interactions are not known. The goals of this proposal are to investigate how resident gut bacteria influence intestinal health through quorum sensing behaviors, to characterize quorum sensing factors directing collective behaviors in B. fragilis, and to define how the host immune system controls B. fragilis quorum sensing.