转录因子IscR调控睾丸酮丛毛单胞菌对重金属锑和头孢氨苄的共抗性机制

项目名称： 转录因子IscR调控睾丸酮丛毛单胞菌对重金属锑和头孢氨苄的共抗性机制

项目编号： No.31500085

项目类型： 青年科学基金项目

立项/批准年度： 2016

项目学科： 生物科学

项目作者： 刘红亮

作者单位： 山东理工大学

项目金额： 20万元

中文摘要： 重金属锑作为治疗寄生虫疾病的药物和抗生素的交叉污染的频率较高。重金属和抗生素的交叉污染迫使细菌产生协同抗性，给人类生存环境及医疗行业带来严峻挑战。目前，关于细菌对锑的抗性机制知之甚少，对锑和抗生素的协同抗性机理更是鲜有报道。本项目前期借助Tn5转座子插入突变技术构建了一株锑(III)抗性/氧化性睾丸酮丛毛单胞菌突变文库，并对该菌进行了全基因组测序，通过分析锑(III)或/和头孢氨苄胁迫下野生型和突变株的表型，初步筛选潜在的偶联锑和头孢氨苄协同抗性相关基因。拟借助比较基因组学，基因敲除和互补，凝胶阻滞，染色质免疫共沉淀，实时定量RT-PCR和LacZ融合蛋白表达等分子生物学技术研究细菌与锑(III)和头孢氨苄抗性相关的基因和调控基因，探索互作机制和调控机理。本项目研究结果将为建立细菌对锑(III)和抗生素共抗性的协同感应调控模型奠定基础，对药物新靶标的发现和新药开发也具有一定理论意义。

中文关键词： 睾丸酮丛毛单胞菌；锑抗性机制；转录调控因子；转录调控；锑和抗生素协同抗性

英文摘要： Antimonials, as the common used drugs for parasitic diseases, have a high frequency of cross-contamination with antibiotics. The cross-contamination leads environmental bacteria to evolve synergistic resistance to antimony (Sb) and antibiotics, which poses serious challenges to the living environment and the healthcare industry. Until now, mechanism of bacterial resistance to Sb is poorly understood, to say nothing of the mechanism of microbial synergistic resistance to Sb and antibiotics. In the prophase of this project, we have constructed a mutant library of a Comamonas testosterone strain with the ability to resist and oxidize Sb(III) using Tn5 transposon insertion mutagenesis. The whole-genome of the bacterium was sequenced. By phenotypic analyses of wild-type and mutant strain of C. testosterone under duress of Sb(III) and/or cephalexin, we performed the initial screening of potential synergistic genes coupling Sb and cephalexin resistance. Based on these preliminary results，we subsequently plan to study the bacterial Sb(III)/cephalexin resistant genes and related regulatory genes, and to explore bacterial-Sb(III)/cephalexin interaction and regulation mechanism by means of the comparative genomics, gene knockout and complementation, electrophoretic mobility shift assay (EMSA), chromatin immunoprecipitation (ChIP), real-time quantitative RT-PCR, LacZ fusion protein expression and other molecular biology techniques. The results of this project will not only contribute to propose a model of synergistic induction regulation for bacterial co-resistance to Sb(III) and antibiotic, but also lay a certain foundation for new drug targets discovery and drug development.

英文关键词： Comamonas testosteroni;antimony resistance mechanism;transcription regulator;transcriptional regulation;co-resistance of antimony and antibiotic