BACTERIAL ADHESION IN THE MICROECOLOGY OF THE LARGE GUT

大肠微生态中的细菌粘附

• 批准号: 3130039
• 负责人: ROLF G FRETER
• 金额: $ 1.1万
• 依托单位: UNIVERSITY OF MICHIGAN AT ANN ARBOR
• 依托单位国家: 美国
• 财政年份: 1988
• 资助国家: 美国
• 起止时间: 1988-12-01 至 1989-03-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/3130039
• 关键词: Bacteroides; Escherichia coli; Fusobacterium; Propionibacteriaceae; cell adhesion; ecology; gastrointestinal epithelium; host organism interaction; laboratory mouse; laboratory rabbit; large intestine; membrane activity; microorganism classification; microorganism culture

Despite the importance of the indigenous microflora of the large intestine to human health and disease, the mechanisms which control its composition are unknown, because (a) experimental models used in the past were inadequate, and (b) the flora is controlled by the interplay of numerous control mechanisms. Consequently, studies of single mechanisms cannot yield an understanding of the whole. We plan to overcome these shortcomings (a) by using continuous flow (CF) cultures of mouse cecal flora, as well as conventional mice as experimental models, and (b) by constructing mathematical models of the interplay among ecologic control mechanisms. A major part of the proposed project is to test a hypothesis generated by an earlier mathematical model namely, that bacterial adhesion in the large intestine is not necessary for colonization of the large intestine, but is required to maintain the stability of the flora. We plan to identify a number of strains of indigenous species (E. coli, Bacteroides sp., Fusobacterium sp., Eubacterium sp.) as to their ability to (a) adhere to epithelial cells, (b) adhere to the surfaces of other indigenous bacteria that are constituents of the surface layers of the large gut, (c) associate with the mucus gel, or (d) adhere poorly to any of these structures. The ability of these strains to colonize mice or CF cultures will be tested. The mathematical model will be improved as necessary, until it is able to closely simulate the observed population dynamics. Throughout the study we will maintain a continuous interplay between experimental and mathematical approaches. In addition to the above studies, we plan to expand our present mathematical model of plasmid transfers in the large intestine. This model currently is based on the assumption of interactions occurring among freely suspended bacteria. We will use the data on adhesion in the gut and in CF cultures generated in the above described work to model plasmid transfer among adherent bacterial populations. We expect eventually to produce a combined mathematical model which can account for plasmid transfer among adherent as well as suspended bacterial populations in the large intestine.

尽管大肠的土著菌群很重要 对于人类健康和疾病，控制其组成的机制 是未知的，因为（a）过去使用的实验模型是 不足，（b）菌群受到许多相互作用的控制 控制机制。 因此，对单个机制的研究不能 对整体产生理解。 我们计划克服这些 使用连续流（CF）小鼠盲肠的缺点（a） 菌群以及常规小鼠作为实验模型，（b） 在生态控制之间构建相互作用的数学模型 机制。 拟议项目的主要部分是检验假设 由较早的数学模型（即细菌粘附）产生 大肠不是大肠所必需的 肠道，但必须保持植物群的稳定性。 我们计划 鉴定许多土著物种菌株（大肠杆菌，菌落 sp。，fusobacterium sp。，Eubacterium sp。）关于它们的能力 到上皮细胞，（b）粘附于其他土著的表面 细菌是大肠道表面层的成分，（c） 与粘液凝胶相关，或（d）粘附不当 结构。 这些菌株定居小鼠或CF培养物的能力 将进行测试。 数学模型将在必要时改进 直到能够密切模拟观察到的种群动态。 在整个研究中，我们将保持连续的相互作用 实验和数学方法。 除了上述 研究，我们计划扩大当前质粒的数学模型 在大肠中转移。 该模型当前基于 自由悬浮细菌之间发生相互作用的假设。 我们 将使用有关肠道和在CF中产生的CF培养物中的粘附数据 上述工作以模拟粘附细菌之间的质粒转移 人群。 我们希望最终产生一个组合的数学模型 可以说明粘附和悬浮的质粒转移 大肠中的细菌种群。