Mechanisms underlying spatial interaction in the oral microbiota

摘要 人类口腔菌斑是一个多微生物群落，其组成在健康和疾病期间变化。 最近的技术进步已经产生了新的信息， 在这些条件下的组成物种还不允许预测之间的直接相互作用 特定的有机体。牙龈上菌斑内可再生结构的生物地理学已经被 通过先进的显微镜方法发现了可能有助于 斑块结构在这些有序结构中的种-种共存暗示着 代谢物介导的相互作用。我们的全球假设是，健康的邻近物种 菌斑生物膜具有特定的代谢和物理相互作用， 这个社区的组成结构。为了识别相邻的 物种，我们必须确定哪些物种共同存在于体内。初步数据显示， 存在高度丰富的马鲁霍棒状杆菌和副流感嗜血杆菌细菌物种 与几种链球菌属直接相邻。这表明它们必须能够耐受pH和氧化 口腔链球菌产生的压力。直接成像进一步表明，一些物种直接结合到 彼此或相互与宿主中间体如唾液蛋白结合。依恋的物理手段 梭matruchotii和H.副流感菌与链球菌属是未知的。这项建议会 确定哪些链球菌与C. matruchotii和H.副流感病毒 显微镜（目的1）。它还将确定C. matruchotii和H.副流感病毒参与交叉 与链球菌产生的代谢物的摄食相互作用，并将确定机制， 通过转录组分析，突变体库，细菌用于耐受pH和氧化应激 分析和定量代谢物测量（目标2）。最后，我们的建议将确定物理 由细菌产生的因子，负责不同物种之间的共粘附。这些将 通过C. matruchotii和H.副流感病毒， 与已知相互作用的链球菌属物种组合。本提案的目的是确定 健康龈上菌斑中的相互作用物种，并表征 他们，揭示他们如何可能有助于斑块的结构和组成。我们的理由是， 将确定促进健康斑块中高度丰富的生物体之间相互作用的机制 并鉴定候选物种及其相关的相互作用，用于益生菌或预防性 采取干预措施管理口腔菌斑群落，以预防机会性感染。

ABSTRACT Human oral plaque is a polymicrobial community whose composition varies during health and disease. Recent advances in technology have yielded new information on the identity and abundance of constituent species during these conditions yet do not allow predictions of direct interactions between specific organisms. The biogeography of reproducible structures within supragingival plaque has been characterized through advanced microscopy methods suggesting key organisms that may help arrange plaque structure. Species-species co-proximity within these ordered structures is suggestive of metabolite mediated interactions between them. Our global hypothesis is that adjacent species in healthy plaque biofilms have specific metabolic and physical interactions that shape both the physical and compositional structure of this community. To identify mechanistic interactions between adjacent species, we must determine which species exist together in vivo. Preliminary data indicates that the highly abundant Corynebacterium matruchotii and Haemophilus parainfluenzae bacterial species exist directly adjacent to several Streptococcus spp. suggesting they must be able to tolerate pH and oxidative stress produced by oral streptococci. Direct imaging further suggests that some species bind directly to each other or mutually to a host intermediate such as salivary protein. The physical means of attachment for C. matruchotii and H. parainfluenzae to Streptococcus spp. are unknown. This proposal will determine which Streptococcus species interact with C. matruchotii and H. parainfluenzae via microscopy (Aim 1). It will also determine if C. matruchotii and H. parainfluenzae participate in cross- feeding interactions with streptococcal produced metabolites and will identify mechanisms that either bacterium uses to tolerate pH and oxidative stress through transcriptome analyses, mutant library assays, and quantitative metabolite measurements (Aim 2). Lastly, our proposal will determine physical factors produced by bacteria that are responsible for co-adhesion between different species. These will be identified by direct and random mutagenesis of C. matruchotii and H. parainfluenzae and tested in combination with known interacting Streptococcus species. The goal of this proposal is to identify interacting species in healthy supragingival plaque and characterize mechanistic interactions between them, revealing how they may contribute to plaque structure and composition. Our rationale is that we will identify mechanisms that promote interactions between highly abundant organisms in healthy plaque and identify candidate species and their associated interactions for use in probiotic or prophylactic interventions to manage oral plaque communities to prevent opportunistic infection.