Mechanisms underlying spatial interaction in the oral microbiota

摘要 人类口腔菌斑是一个多种微生物群落，其组成在健康和疾病期间会发生变化。 最近的技术进步已经产生了关于身份和丰度的新信息 在这些条件下的组成物种但不允许预测之间的直接相互作用 特定的生物体。龈上斑块内可重复结构的生物地理学已被 通过先进的显微镜方法进行表征，表明可能有助于安排的关键生物体 斑块结构。这些有序结构中的物种与物种之间的邻近性表明 代谢物介导它们之间的相互作用。我们的全球假设是，健康的邻近物种 斑块生物膜具有特定的代谢和物理相互作用，可塑造身体和身体 该社区的组成结构。识别相邻之间的机械相互作用 物种，我们必须确定哪些物种在体内共同存在。初步数据表明 存在高度丰富的马特鲁霍蒂棒状杆菌和副流感嗜血杆菌细菌种类 直接邻近几种链球菌属。表明它们必须能够耐受 pH 值和氧化 口腔链球菌产生的压力。直接成像进一步表明某些物种直接结合 彼此或与宿主中间体例如唾液蛋白相互结合。物理附着方式 对于 C. matruchotii 和 H. parainfluenzae 到 Streptococcus spp.未知。该提案将 确定哪些链球菌与 C. matruchotii 和 H. parainfluenzae 相互作用 显微镜检查（目标 1）。它还将确定 C. matruchotii 和 H. parainfluenzae 是否参与交叉感染 与链球菌产生的代谢物的喂养相互作用，并将确定以下机制： 细菌通过转录组分析、突变体库来耐受 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 细菌产生的导致不同物种之间共同粘附的因子。这些将 通过 C. matruchotii 和 H. parainfluenzae 的直接和随机诱变进行鉴定，并在 与已知相互作用的链球菌物种组合。该提案的目标是确定 健康龈上菌斑中相互作用的物种并表征之间的机械相互作用 揭示它们如何影响斑块结构和组成。我们的理由是我们 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 并确定用于益生菌或预防性药物的候选物种及其相关相互作用 管理口腔菌斑群落以预防机会性感染的干预措施。

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.