饥饿诱导的反转录子Ec107表达及鸟苷四磷酸（ppGpp）在多拷贝单链DNA产生中的作用。
Starvation-induced expression of retron-Ec107 and the role of ppGpp in multicopy single-stranded DNA production.
作者信息
Herzer P J
机构信息
Department of Microbiology, Biozentrum, University of Basel, Switzerland.
出版信息
J Bacteriol. 1996 Aug;178(15):4438-44. doi: 10.1128/jb.178.15.4438-4444.1996.
Multicopy single-stranded DNA is found as a small single-stranded RNA-DNA complex in certain wild-type strains of Escherichia coli as well as in other gram-negative bacteria. Using the promoter region of the previously characterized retron-Ec107 from E. coli ECOR70, I constructed a chromosomally located lacZ operon fusion. Examination of expression from the PEc107 promoter showed that activity increased sharply when cells entered stationary phase in rich medium or when they were starved for phosphate. The nucleotide guanosine-3',5'-bispyrophosphate was found to be a positive regulator of retron-Ec107 expression. Its presence is required for starvation-induced transcription of retron-Ec107 and multicopy single-stranded DNA production. It was also found that expression from the retron promoter is independent of the sigma factor sigmaS.
在某些大肠杆菌野生型菌株以及其他革兰氏阴性细菌中，多拷贝单链DNA以一种小的单链RNA - DNA复合物形式存在。利用先前已鉴定的来自大肠杆菌ECOR70的逆转录子Ec107的启动子区域，我构建了一个位于染色体上的lacZ操纵子融合体。对PEc107启动子表达的检测表明，当细胞在丰富培养基中进入稳定期或缺乏磷酸盐时，活性会急剧增加。发现核苷酸鸟苷 - 3',5'-双焦磷酸是逆转录子Ec107表达的正调控因子。其存在是饥饿诱导逆转录子Ec107转录和多拷贝单链DNA产生所必需的。还发现逆转录子启动子的表达独立于σ因子σS。
Zotero 插件