鸭疫里默氏杆菌整合子对其捕获和表达耐药基因盒效率的调控作用

项目名称： 鸭疫里默氏杆菌整合子对其捕获和表达耐药基因盒效率的调控作用

项目编号： No.31201935

项目类型： 青年科学基金项目

立项/批准年度： 2013

项目学科： 畜牧学与草地科学、兽医学、水产学

项目作者： 郑福英

作者单位： 中国农业科学院兰州兽医研究所

项目金额： 23万元

中文摘要： 整合子是一种基因捕获和表达的遗传单位，可通过位点特异性重组，获得多种外源耐药基因，使细菌产生多重耐药性。整合子对外源基因盒的捕获存在完整而精细的调控机制，但这一机制尚未明了。本研究在详细分析鸭疫里默氏杆菌（RA）I类整合子序列结构的基础上，探讨RA I类整合子的不同序列结构对其捕获与表达外源耐药基因盒效率的调控作用。从驱动基因盒表达的不同启动子Pant类型、基因盒距离Pant的远近、不同长度的attC位点以及不同类型的耐药基因盒等四个方面，运用重叠PCR、实时定量PCR、SDS-PAGE、Western blot、MIC和MBC抗菌药物敏感性试验等技术，明确RA I类整合子自身构成元件对耐药基因盒捕获频率、基因盒转录和翻译水平的影响，阐明RA整合子捕获与表达耐药基因盒的自身调控作用，为进一步揭示整合子-基因盒系统介导的细菌多重耐药机制及相关新药物的开发提供科学依据。

中文关键词： 鸭疫里默氏杆菌；整合子；捕获；转录；表达

英文摘要： Integron is a genetic element with the ability to capture and express genes.It acquires drug-resistant genes embedded in exogenous gene cassettes by specific position recombination, offering bacteria with multi-drug resistance. There is a ingenious mechanism for integron capturing exogenous antibiotic resistance gene cassettes,but this mechanism remains elusive so far. The purpose of this study is to probe the regulation of integron capturing and expressing exogenous antibiotic resistance gene cassettes in Riemerella anatipestifer(RA) based on the detailed analysis of the sequence structures of RA class 1 integron. To clarify the self-regulatory effects and regulation mechanisms of the RA integron structures on the recombination frequencies, transcriptional and translational levels of the gene cassettes, the efficencies are measured for RA integron capturing and expressing gene cassettes mediated respectively by different promoter Pants, attC sites, gene cassettes and the distances between gene cassette and Pant by overlap PCR, real time quantitative PCR, SDS-PAGE, Western blot, MIC and MBC antibiotic susceptibility tests. It will provide a theoretical basis for further elucidating multiple-antibiotic-resistant mechanisms mediated by integron gene cassette system, and developing novel drugs to decrease the emerg

英文关键词： Riemerella anatipestifer；integron；capture；transcription；expression