Departamento de Genética, Facultad de Biología, Universidad de Sevilla, Apartado 1095, 41080, Sevilla, Spain.
Department of Medical Biochemistry and Microbiology, Uppsala University, 751 23, Uppsala, Sweden.
Sci Rep. 2019 Aug 2;9(1):11261. doi: 10.1038/s41598-019-47650-2.
We describe a portable epigenetic switch based on opvAB, a Salmonella enterica operon that undergoes bistable expression under DNA methylation control. A DNA fragment containing the opvAB promoter and the opvAB upstream regulatory region confers bistability to heterologous genes, yielding OFF and ON subpopulations. Bistable expression under opvAB control is reproducible in Escherichia coli, showing that the opvAB switch can be functional in a heterologous host. Subpopulations of different sizes can be produced at will using engineered opvAB variants. Controlled formation of antibiotic-resistant and antibiotic-susceptible subpopulations may allow use of the opvAB switch in the study of bacterial heteroresistance to antibiotics.
我们描述了一种基于 opvAB 的便携式表观遗传开关，opvAB 是沙门氏菌属中的一个操纵子，在 DNA 甲基化控制下进行双稳态表达。包含 opvAB 启动子和 opvAB 上游调控区的 DNA 片段赋予异源基因双稳态表达，产生 OFF 和 ON 亚群。opvAB 控制下的双稳态表达在大肠杆菌中具有重现性，表明 opvAB 开关可以在异源宿主中发挥功能。使用工程化的 opvAB 变体可以随意产生不同大小的亚群。抗生素耐药和抗生素敏感亚群的可控形成可能允许在研究细菌对抗生素的异源耐药性时使用 opvAB 开关。
