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. 1972 Feb;12(2):133–156. doi: 10.1016/S0006-3495(72)86076-4

Action of Ionizing Radiation on Sensitive Strains of Escherichia coli B

Ernest C Pollard, Anna Tilberg
PMCID: PMC1484059  PMID: 4550650

Abstract

Strain B8-11 has been found to be very sensitive to postirradiation DNA degradation. Up to 98% of the DNA is degraded at optimum doses. The amount of residual DNA correlates with the retention of colony-forming ability (CFA). Studies of rates of degradation as a function of dose agree with the concept that a degrading lesion causes a definite rate of degradation and that increased numbers of lesions produce proportionally faster rates. By observing the burst size of T7 phage which uses host DNA it has been established that DNA degradation occurs in an all-or-nothing fashion in a unit which is present two or three times per cell. Degradation is enzymatic and the enzyme system is already present in the cell as evidenced by the rapid onset of degradation. DNA synthesis continues in cells that have lost some chromosomes by degradation. Single-cell division patterns show that recovery from “sublethal” damage can occur even in this sensitive cell. Recovery in preirradiation oxygenated cells differs from that in nitrogenated cells.

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Selected References

These references are in PubMed. This may not be the complete list of references from this article.

  1. Alper T. Low oxygen enhancement ratios for radiosensitive bacterial strains, and the probable interaction of two types of primary lesion. Nature. 1968 Mar 2;217(5131):862–863. doi: 10.1038/217862a0. [DOI] [PubMed] [Google Scholar]
  2. Donch J., Greenberg J. Loci of radiation sensitivity in Bs strains of Escherichia coli. Genet Res. 1968 Apr;11(2):183–191. doi: 10.1017/s0016672300011356. [DOI] [PubMed] [Google Scholar]
  3. ELKIND M. M., SUTTON H. Radiation response of mammalian cells grown in culture. 1. Repair of X-ray damage in surviving Chinese hamster cells. Radiat Res. 1960 Oct;13:556–593. [PubMed] [Google Scholar]
  4. Grady L. J., Pollard E. C. Ionizing radiation-initiated degradation of deoxyribonucleic acid in bacteria. A possible role for defective prophage. Radiat Res. 1968 Oct;36(1):68–86. [PubMed] [Google Scholar]
  5. Huston D. C., Pollard E. C. DNA degradation in Escherichia coli 15T-L- induced by fast proton bombardment. Biophys J. 1967 Sep;7(5):555–565. doi: 10.1016/S0006-3495(67)86606-2. [DOI] [PMC free article] [PubMed] [Google Scholar]
  6. Kaplan H. S. DNA-strand scission and loss of viability after x irradiation of normal and sensitized bacterial cells. Proc Natl Acad Sci U S A. 1966 Jun;55(6):1442–1446. doi: 10.1073/pnas.55.6.1442. [DOI] [PMC free article] [PubMed] [Google Scholar]
  7. Kelly T. J., Jr, Smith H. O. A restriction enzyme from Hemophilus influenzae. II. J Mol Biol. 1970 Jul 28;51(2):393–409. doi: 10.1016/0022-2836(70)90150-6. [DOI] [PubMed] [Google Scholar]
  8. LABAW L. W. The origin of phosphorus in the T1, T5, T6, and T7 bacteriophages of Escherichia coli. J Bacteriol. 1953 Oct;66(4):429–436. doi: 10.1128/jb.66.4.429-436.1953. [DOI] [PMC free article] [PubMed] [Google Scholar]
  9. Pollard E. C., Davis S. A. The action of ionizing radiation on transcription (and translation) in several strains of Escherichia coli. Radiat Res. 1970 Feb;41(2):375–399. [PubMed] [Google Scholar]
  10. Studier F. W. The genetics and physiology of bacteriophage T7. Virology. 1969 Nov;39(3):562–574. doi: 10.1016/0042-6822(69)90104-4. [DOI] [PubMed] [Google Scholar]
  11. Yeisley W. G., Pollard E. C. Division patterns from single Escherichia coli cells. Biophys J. 1969 Jul;9(7):925–949. doi: 10.1016/S0006-3495(69)86427-1. [DOI] [PMC free article] [PubMed] [Google Scholar]

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