Supercoils in prokaryotic DNA restrained in vivo.
- 1 March 1980
- journal article
- research article
- Published by Proceedings of the National Academy of Sciences in Proceedings of the National Academy of Sciences
- Vol. 77 (3) , 1331-1335
- https://doi.org/10.1073/pnas.77.3.1331
Abstract
Cells of Escherichia coli containing the plasmid F were .gamma.-irradiated with various doses to introduce determined numbers of single-strand breaks in the F DNA. The cells were then incubated to permit repair of the breaks while DNA gyrase was inhibited with coumermycin to limit restoration of any relaxed supercoils. Repaired, covalently continuous F DNA was isolated and its superhelical density was measured by 2 different methods. Both indicated that a major part (50-60%) of the negative superhelical turns were maintained in the repaired molecules, suggesting that the supercoils are restrained in vivo.This publication has 30 references indexed in Scilit:
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