DNA damage produced by exposure of supercoiled plasmid DNA to high- and low-LET ionizing radiation: Effects of hydroxyl radical quenchers. DNA breakage, neutrons, OH radicals
Abstract
A supercoiled plasmid of 7300 base pairs was isolated and exposed in an aqueous environment to {sup 60}Co {gamma} rays and JANUS 0.85 MeV fission-spectrum neutrons. Dose responses for the production of single-strand breaks (SSBs), double-strand breaks (DSBs) and alkali-labile sites (ALSs) were compared with computations made from the conversion of the supercoil to its relaxed and linear forms. The relative biological effectiveness (RBE) for production of SSBs and DSBs was similar to that previously measured in the cellular environment. The RBE for destruction of genetic transforming activity of M13 viral DNA followed that for DNA damage. This is in contrast to the situation for biological effects such as lethality, mutagenesis, and cellular transformation measured in mammalian cells, where the RBE values are reversed. The role of hydroxyl (OH) radical in DNA damage induction by neutrons was investigated by exposure of plasmid in the presence of known quenchers of this species. Of four quenchers tested, all were able to reduce the yields of both SSBs and DSBs. These findings are consistent with a model for SSB and DSB induction by high linear energy transfer that involves OH radical mediation.
- Authors:
-
- Argonne National Lab., IL (United States)
- Univ. of Maryland, Baltimore, MD (United States). Center for Marine Biotechnology
- Publication Date:
- Research Org.:
- Argonne National Lab., IL (United States)
- Sponsoring Org.:
- USDOE, Washington, DC (United States)
- OSTI Identifier:
- 10172487
- Report Number(s):
- ANL/BIM/PP-78690
ON: DE94016382; TRN: 94:014848
- DOE Contract Number:
- W-31109-ENG-38
- Resource Type:
- Technical Report
- Resource Relation:
- Other Information: PBD: [1994]
- Country of Publication:
- United States
- Language:
- English
- Subject:
- 63 RADIATION, THERMAL, AND OTHER ENVIRON. POLLUTANT EFFECTS ON LIVING ORGS. AND BIOL. MAT.; 59 BASIC BIOLOGICAL SCIENCES; DNA; STRAND BREAKS; PLASMIDS; BIOLOGICAL RADIATION EFFECTS; HYDROXYL RADICALS; RESPONSE MODIFYING FACTORS; LET; RBE; 560120; 550200; RADIATION EFFECTS ON BIOCHEMICALS, CELLS, AND TISSUE CULTURE; BIOCHEMISTRY
Citation Formats
Peak, J.G., Ito, T., Peak, M.J., and Robb, F.T.. DNA damage produced by exposure of supercoiled plasmid DNA to high- and low-LET ionizing radiation: Effects of hydroxyl radical quenchers. DNA breakage, neutrons, OH radicals. United States: N. p., 1994.
Web. doi:10.2172/10172487.
Peak, J.G., Ito, T., Peak, M.J., & Robb, F.T.. DNA damage produced by exposure of supercoiled plasmid DNA to high- and low-LET ionizing radiation: Effects of hydroxyl radical quenchers. DNA breakage, neutrons, OH radicals. United States. doi:10.2172/10172487.
Peak, J.G., Ito, T., Peak, M.J., and Robb, F.T.. Mon .
"DNA damage produced by exposure of supercoiled plasmid DNA to high- and low-LET ionizing radiation: Effects of hydroxyl radical quenchers. DNA breakage, neutrons, OH radicals". United States.
doi:10.2172/10172487. https://www.osti.gov/servlets/purl/10172487.
@article{osti_10172487,
title = {DNA damage produced by exposure of supercoiled plasmid DNA to high- and low-LET ionizing radiation: Effects of hydroxyl radical quenchers. DNA breakage, neutrons, OH radicals},
author = {Peak, J.G. and Ito, T. and Peak, M.J. and Robb, F.T.},
abstractNote = {A supercoiled plasmid of 7300 base pairs was isolated and exposed in an aqueous environment to {sup 60}Co {gamma} rays and JANUS 0.85 MeV fission-spectrum neutrons. Dose responses for the production of single-strand breaks (SSBs), double-strand breaks (DSBs) and alkali-labile sites (ALSs) were compared with computations made from the conversion of the supercoil to its relaxed and linear forms. The relative biological effectiveness (RBE) for production of SSBs and DSBs was similar to that previously measured in the cellular environment. The RBE for destruction of genetic transforming activity of M13 viral DNA followed that for DNA damage. This is in contrast to the situation for biological effects such as lethality, mutagenesis, and cellular transformation measured in mammalian cells, where the RBE values are reversed. The role of hydroxyl (OH) radical in DNA damage induction by neutrons was investigated by exposure of plasmid in the presence of known quenchers of this species. Of four quenchers tested, all were able to reduce the yields of both SSBs and DSBs. These findings are consistent with a model for SSB and DSB induction by high linear energy transfer that involves OH radical mediation.},
doi = {10.2172/10172487},
journal = {},
number = ,
volume = ,
place = {United States},
year = {Mon Aug 01 00:00:00 EDT 1994},
month = {Mon Aug 01 00:00:00 EDT 1994}
}
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