sRNA与群体感应系统相互作用调控乳杆菌细菌素合成机制研究

项目名称： sRNA与群体感应系统相互作用调控乳杆菌细菌素合成机制研究

项目编号： No.31471707

项目类型： 面上项目

立项/批准年度： 2015

项目学科： 农业科学

项目作者： 张香美

作者单位： 河北经贸大学

项目金额： 80万元

中文摘要： sRNA是细菌中普遍存在的一类长度为40-500nt的非编码RNA，在对环境胁迫的应答过程中发挥着重要作用。sRNA和群体感应(quorum sensing,QS)系统交互作用，在细菌生命活动过程中发挥着广泛的调控作用。本项目在产细菌素乳杆菌QS调控研究的基础上，采用鸟枪克隆法克隆sRNA，筛选乳杆菌sRNA，并经Northern杂交、实时荧光定量RT-PCR等确定环境胁迫相关sRNA；利用生物信息学软件对候选sRNA进行靶基因预测，选择与乳杆菌细菌素合成相关靶基因进行验证；构建乳杆菌sRNA基因、靶基因以及QS系统组分hpk、rr缺失突变株及其互补株，研究sRNA在细菌素合成中的作用以及sRNA与QS系统相互作用对乳杆菌细菌素合成的影响，解析环境胁迫因子影响乳杆菌细菌素合成的分子机制。研究结果不仅可为实现乳杆菌细菌素的稳定表达提供理论依据，同时也可为产细菌素乳杆菌在食品中的应用奠定基础。

中文关键词： sRNA；细菌素；调控机制；环境胁迫；群体感应系统

英文摘要： Bacterial sRNAs are a class of non-coding RNAs with 40-500 nt. These sRNAs play important roles in response to environmental stress. Interaction of sRNA and quorum sensing(QS) system plays an extensive role in the regulation of life activities in bacteria. On the basis of the research of QS regulation in bacteriocinogenic Lactobacillus spp., this project will clone sRNAs using shot-gun cloning approach,then Lactobacillus spp. sRNAs will be selected. The environmental stress associated sRNAs in Lactobacillus spp. will be identified by Northern blotting, real-time fluorescent quantitative RT-PCR,etc. The target genes of candiate sRNAs will be predicted using bioinformatics software, the target genes related to bacteriocin synthesis in Lactobacillus spp. will be selected, then they will be further verified. A series of gene deletion mutants including hpk and rr, components of quorum sensing system in bacteriocinogenic Lactobacillus spp., gene deletion mutants or sRNA gene deletion mutants and the corresponding complementary strains will be constructed, then the function of sRNA in bacteriocin synthesis and the effect of the interaction between sRNA and QS system on bacteriocin synthesis will be studied to reveal the molecular mechanism of the effect of environmental stress factor on bacteriocin production in Lactobacillus spp.. The results not only provide a theoretical basis for stable expression of bacteriocin in Lactobacillus spp., but also lay foundation for the application of bacteriocinogenic Lactobacillus spp.in food.

英文关键词： Small RNA;Bacteriocin;Regulation mechanism;Environmental stress;Quorum sensing system