阴沟肠杆菌复合菌群的系统分类及其在浙江省主要饮用水源地的多样性分布与风险评估

项目名称： 阴沟肠杆菌复合菌群的系统分类及其在浙江省主要饮用水源地的多样性分布与风险评估

项目编号： No.31200003

项目类型： 青年科学基金项目

立项/批准年度： 2013

项目学科： 微生物学、植物学

项目作者： 朱勃

作者单位： 浙江大学

项目金额： 22万元

中文摘要： 阴沟肠杆菌是普遍存在于环境中，但能引起严重的人体病害的一类条件致病菌。国内外的研究表明阴沟肠杆菌并不是一个单一种，而是一类表型相近，但基因型有所差异的复合菌群（Ecc）。然而Ecc的种群类型及其系统分类地位尚不明确，且相关的环境中的多样性及其何种基因型对人体具有的潜在风险也尚无研究。前期我们在桑树及甘蔗根围共分离到了200余株Ecc，以此为线索，我们开展相应的实验，初步结果表明Ecc不仅遗传背景非常复杂、性状差异巨大且相应的代表菌株在系统分类图上无法形成单系起源。因此，本研究拟通过高通量测序、分子生物学、传统的生理生化方法及小鼠活体毒力测试，通过对浙江省主要饮用水源地的水源样本进行相关分析，一方面为深入理解并解决Ecc的系统分类极其多样性问题提供重要的理论依据,另一方面了解在环境中能潜在的对人体产生潜在威胁的Ecc优势菌群，并提供初步的风险评估。

中文关键词： 阴沟肠杆菌；微环境；三代测序；适应性；

英文摘要： Enterobacter cloacae is a severe human opportunistic bacterial pathogen, which is widely exist in the environment. Recent researches have suggested that The Enterobacter cloacae complex (Ecc) is a collection of several genotypically distinct but phenotypically similar species. However, the phylogenetic systematic about different species in Ecc, the Ecc ecological diversity and the specific genotypes that are potential risk for human beings are still largely unexplored. Until now, we have isolated more than 200 Ecc strains from the rhizosphere of mulberry and sugarcane. Preliminary experimental results indicated that the genetic backgrounds and phenotypic traits about these Ecc strains are complex and divergent. In addition, monophyly about the type strains from Ecc cannot be obtained by reconstructing the phylogenetic tree using 16S rRNA sequences. In this research, High-throughput sequencing, molecular biology, physical and biochemical analysis and mice virulence test assays are going to be used to analyze the water samples collected from the major potable water sources in Zhejiang Province. It will not only provide the important fundamental information to understand and solve the difficulties in phylogenetic systematic and diversity about Ecc but also will give us a preliminary risk assessment about dominant g

英文关键词： Enterobacter cloacae；niche；Pacbio；adaptation；