pPopctrl质粒中Tn5转座子的插入对AHL信号分子生成的影响
关键词： 细菌自杀；pPopctrl质粒；Tn5转座子；IPTG；AHL
Effect of insertion of transposon Tn5 in plasmid pPopctrl on the formation of AHL signaling molecules
Abstract: Suicide behavior （wild-type）of bacterium is a natural phenomenon. Study on gain and maintenance of suicide phenomenon and effect of this phenomenon on the evolution of bacterial population is important in theory and practice. In the process of bacterium suicide, mutation is inevitable（mutant）. Difference between wild-type and mutant is the insertion of transposon Tn5 on plasmid pPopctrl. It is proved that it is enough to fight IPTG induced suicide by inserting transposon to plasmid. Whether insertion of transposon Tn5 influences generation of signaling molecule AHL has not yet known. We have got two strains named 107 strain and 125 strain in previous work. In this study, plasmid DNA was extracted from 125 strain and was transformed into 107 strain. Then we got a new strain and named it as 107’ strain (with 'top10F' as the host, plasmid containing only pLuxCcdB3(from 107 strain) and pLuxR2(from 125 strain). We compared growth patterns of 107' in the supernatant of wild-type strain and mutant strain of their TBK medium (respectively, containing IPTG, no IPTG as control) and found that there were significant differences :107’ strain in different TBK supernatants of wild-type strains occurred suicide behavior while 107’ strain in different TBK supernatant of mutants grown well.We finally inferred that the insertion of transposon Tn5 has influence on generation of signaling molecule AHL.
Key Words: bacterium suicide; pPopctrl plasmid;Tn5 transposons ; IPTG; AHL
目录
1 绪论 1
1.1 细菌的自杀行为 1
1.2群体感应现象 1
1.3 AHL信号分子概述 1
1.4 细菌自杀基因回路 2
1.5 细菌的突变 3
1.6本课题研究的内容和意义 4
2.1使用的材料试剂、仪器设备 5
2.2 采取的方法 6
2.2.1 培养基配制 6
2.2.2 基本操作 7
2.2.3 质粒的抽提、检测、转化 7
2.2.4 CFU数据测定 10
2.2.5酶标仪法测定生长曲线 10
3实验过程及结果分析 12
3.1比较野生型、突变型及新菌种107’在新鲜TBK培养中的生长差异 12
3.1.1转化新菌种及菌种的确定 12
3.1.2比较野生型、突变型及新菌种在新鲜TBK培养基中的生长特征 13
3.2 CFU法比较107’菌种在野生型及突变型TBK上清液中的生长差异 14