DNA supercoiling and suppression of the leu-500 promoter mutation.
نویسندگان
چکیده
top mutations (formerly supX) eliminate DNA topoisomerase I activity and suppress the leu-500 promoter mutation in Salmonella typhimurium (K. M. Overbye, S. K. Basu, and P. Margolin, Cold Spring Harbor Symp. Quant. Biol. 47:785-791, 1983). Sublethal doses of coumermycin which reduce intracellular levels of supercoiling activity in a top mutant eliminated suppression of the leu-500 mutation. This result provides evidence that increased DNA supercoiling suppresses the leu-500 promoter mutation in top mutants.
منابع مشابه
Suppression of leu-500 mutation in topA+ Salmonella typhimurium strains. The promoter relay at work.
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عنوان ژورنال:
- Journal of bacteriology
دوره 164 2 شماره
صفحات -
تاریخ انتشار 1985