Deoxyribonucleic acid repair in a highly radiation-resistant strain of Salmonella typhimurium.

TitleDeoxyribonucleic acid repair in a highly radiation-resistant strain of Salmonella typhimurium.
Publication TypeJournal Article
Year of Publication1973
AuthorsDavies, R, Sinskey, AJ, Botstein, D
JournalJ Bacteriol
Volume114
Issue1
Pagination357-66
Date Published1973 Apr
ISSN0021-9193
KeywordsCarbon Isotopes, Cell Survival, Centrifugation, Density Gradient, Cobalt Isotopes, Deoxyadenosines, DNA Repair, DNA, Bacterial, DNA, Single-Stranded, Molecular Weight, Radiation Effects, Salmonella typhimurium, Thymidine, Thymine, Tritium
Abstract

Deoxyribonucleic acid repair was studied in gamma-irradiated wild-type Salmonella typhimurium and in a radiation-resistant derivative 20 times more resistant than wild type. After exposure to 20 or 50 krad, the wild-type strain (DB21) degraded 30 to 50% of its prelabeled DNA into acid-soluble fragments, whereas the radioresistant strain degraded less than 15% after 4 h of incubation. Post-irradiation synthesis of DNA in the wild-type strain DB21 was reduced after a dose of 20 krad and totally inhibited after exposure to 200 krad. With radiation-resistant strain, D21R6008, on the other hand, DNA synthesis was delayed after a dose of 200 krad but not inhibited. Doses of 20 and 200 krad produced a similar number of single-strand breaks in the DNA of both strains as determined by zone sedimentation analysis in alkaline sucrose gradients. The radiation-resistant strain D21R6008, on the other hand, DNA synthesis was strand breaks in its DNA and repairs these damages more rapidly than wild-type Salmonella.

DOI10.1128/jb.114.1.357-366.1973
Alternate JournalJ Bacteriol
Citation Key262
PubMed ID4572719
PubMed Central IDPMC251774