Superhelicity and DNA Radiation Sensitivity

901349

07/01/1990

Event
International Conference On Environmental Systems
Authors Abstract
Content
Several underwound families of topoisomers of the plasmid pIB130 were irradiated with fission neutrons at 28 C in TE buffer. Form I DNA followed the expected exponential dependence on dose, and was greater for those DNA molecules characterized by larger linking numbers. The radiation sensitivity was found to be linearly related to average linking difference. We tentatively attribute this enhanced radiation sensitivity to the increased number of transient open states that closed DNA experiences with increasing superhelicity. Radioprotectants enhance decrease in the DNA linking number in the presence of topoisomerase I, suggests that some of the protection conferred may be due to decreases in DNA superhelicity.
Meta TagsDetails
DOI
https://doi.org/10.4271/901349
Pages
10
Citation
Swenberg, C., Holwitt, E., and Speicher, J., "Superhelicity and DNA Radiation Sensitivity," SAE Technical Paper 901349, 1990, https://doi.org/10.4271/901349.
Additional Details
Publisher
Published
Jul 1, 1990
Product Code
901349
Content Type
Technical Paper
Language
English