植物乳杆菌肠道定殖特性及其影响因素

Lactobacillus plantarum is a probiotic widely distributed in fermented food, but its intestinal colonization characteristics and related influential factors were still not clear. Based on the results of our preliminary work, this study will firstly compare the colonization abilities of different L. plantarum strains (type strains, commercial strains and typical strains screened out by our lab with good probiotic functions) in germ-free mice. Then the effects of the genetic background of strains on colonization are evaluated by comparative genomic analysis. Moreover, the physiological properties of the strains including utilization of carbohydrate, tolerance to gastrointestinal tract environment and surface components are investigated to understand their influence on colonization. The relationship between intestinal colonization and probiotic abilities such as gut microbiota regulation is finally investigated. The results of the present study may provide scientific evidence on the intestinal colonization and probiotic characteristics of L. plantarum, and provide further theoretical support for the high-throughput screening of this strain.

植物乳杆菌是一类广泛分布于发酵食品中的益生乳酸菌，但其肠道定殖特性及相关影响因素一直没有得到明确的阐释。本课题以植物乳杆菌的模式株、商业株和本实验室选育得到的功能菌株为研究对象，首先利用无菌鼠模型解析不同菌株的肠道定殖能力；并基于比较基因组学阐明菌株遗传背景与定殖能力的关联；同时解析菌株碳水化合物利用能力、胃肠道环境耐受、表面物质基础等生理特性对定殖能力的影响；进一步整合宏基因组学等技术手段解析菌株定殖能力与肠道菌群调节等益生功能的关联网络。本项目的实施可以为植物乳杆菌菌株的肠道定殖特性及其益生机制提供科学定义，进一步为菌株的高效定向筛选提供理论基础。

植物乳杆菌是一类广泛分布于发酵食品中的益生菌，近年来其益生功能被广泛报道，但其肠道定殖特性及相关影响因素一直没有得到明确的阐释。本课题以植物乳杆菌为研究对象，通过明确不同植物乳杆菌在肠道中结构和组成的差异，探究具有不同定殖能力的菌株对宿主生理的影响；进一步基于比较基因组解析菌株遗传背景，预测并验证菌株生理特性，解析影响植物乳杆菌定殖的关键因素、代谢特征、功能基因及相关表面物质；最后通过验证不同遗传背景、不同定殖能力的菌株对小鼠肠道屏障的保护机制及菌群调节规律的差异，阐明植物乳杆菌定殖对宿主生理影响的机制。本项目的实施可以为植物乳杆菌菌株的肠道定殖特性及其益生机制提供科学定义，进一步为益生菌的高效定向筛选提供理论基础。