单细胞尺度的牙菌斑尿素代谢异质性机制研究

项目名称： 单细胞尺度的牙菌斑尿素代谢异质性机制研究

项目编号： No.31300424

项目类型： 青年科学基金项目

立项/批准年度： 2014

项目学科： 生物科学

项目作者： 杨芳

作者单位： 青岛大学

项目金额： 24万元

中文摘要： 龋病是多细菌参与的慢性感染性疾病，因此认识其病因关键是理解菌群中个体间的功能差异，即"功能异质性"。而牙菌斑内多数细菌难以或尚未被培养，妨碍其异质性解析。单个活体细胞是菌群结构和功能的单位，因此在"单个活体细胞"尺度观察和比较个体功能，可望"跳过"细菌扩增培养这一环节，在最"深"的层面上揭示细胞群体内的功能异质性。针对"牙菌斑中部分成员能够代谢尿素产氨，从而拮抗菌群产酸活性而具抗龋效应"这一假设，申请人将基于原位构建的牙菌斑，运用活体单细胞拉曼光谱分析与分选等非侵害性、原位的新型细胞表征与操作技术，考察菌群中单个活体细胞之间代谢尿素的表型差异与基因型差异；并结合元基因组手段，探讨该异质性在物种、基因等角度的呈现规律，及其在模拟龋病发生过程中的动态变化机制。本研究将建立首个活体单细胞尺度的牙菌斑代谢异质性研究模型，从而为龋病病因学研究提供新思路和新方法。

中文关键词： 龋病；菌群；预测；代谢分选；单细胞

英文摘要： Caries, a polymicrobial infection, is mediated not by a single pathogen,but by a microbial community. Thus understanding the "functional heterogeneity" of individual members in the caries microbiota will be one key to caries etiology. However dissecting the "functional heterogeneity" in plaque microbiota has been difficult as most bacteria in plaque remain uncultured. A single cell is the atomic unit of the structure and function of a microbial community. Therefore interrogation of the activity of both microbial community and its individual members, at the resolution of "a single live cell", will be able to circumvent the need for cell culture/propagation and be capable of unraveling the "deepest" functional heterogeneity in the microbiota. I will test the hypothesis that in plaque microbiota there is functional heterogeneity in ammonia-production from urea, which is important as ammonia-production counters the activity of acid-producing bacteria and thus might be an anti-caries factors. Employing non-invasive phenotyping techniques such as Single-cell Raman Spectroscopy and Raman-activated sorting, as well as single-cell and community genomics/transcriptomics approaches, I will monitor and compare the metabolic activity (as well as the underlying genotypes) of both the plaque microbiota and individual members a

英文关键词： caries；microbiota；prediction；metabolism；single-cell