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J Bacteriol. 1971 Mar; 105(3): 976–983.
PMCID: PMC248526

Repair of Irradiated Transforming Deoxyribonucleic Acid in Wild Type and a Radiation-Sensitive Mutant of Micrococcus radiodurans


The survival of biological activity in irradiated transforming deoxyribonucleic acid (DNA) has been assayed in the wild type and a radiation-sensitive mutant of Micrococcus radiodurans. The frequency of transformation with unirradiated DNA was lower in the mutant to about the same extent as the mutant's increased sensitivity to radiation. However, in both the wild type and the mutant, the irradiated DNA that was incorporated into the bacterial genome was repaired to the same extent as determined by the loss of transforming activity with increasing radiation dose. This applied to DNA irradiated either with ionizing or ultraviolet (UV) radiation. The rate of inactivation of biological activity after UV radiation was the same in any of the DNA preparations tested. For ionizing radiation, the rate of inactivation varied up to 40-fold, depending on the DNA preparation used, but for any one preparation was the same whether assayed in the wild type or the radiation-sensitive mutant. When recipient bacteria were irradiated with ionizing or UV radiation immediately before transformation, the frequency of transformation with unirradiated DNA fell, rapidly and exponentially in the case of the sensitive mutant but in a more complicated fashion in the wild type. The repair of DNA irradiated with ionizing radiation was approximately the same whether assayed in unirradiated or irradiated hosts. Thus, irradiation of the host reduced the integration of DNA but not its repair.

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Selected References

These references are in PubMed. This may not be the complete list of references from this article.
  • Howard-Flanders P. DNA repair. Annu Rev Biochem. 1968;37:175–200. [PubMed]
  • Hutchinson F, Hales HB. Mechanism of the sensitization of bacterial transforming DNA to ultraviolet light by the incorporation of 5-bromouracil. J Mol Biol. 1970 May 28;50(1):59–69. [PubMed]
  • LACKS S. Molecular fate of DNA in genetic transformation of Pneumococcus. J Mol Biol. 1962 Jul;5:119–131. [PubMed]
  • Mahler I. Characteristics of an ultraviolet irradiation sensitive strain of Bacillus subtilis. Biochem Biophys Res Commun. 1965 Nov 22;21(4):384–391. [PubMed]
  • Moseley BE. The isolation and some properties of radiation-sensitive mutants of Micrococcus radiodurans. J Gen Microbiol. 1967 Nov;49(2):293–300. [PubMed]
  • Moseley BE. Repair of ultraviolet radiation damage in sensitive mutants of Micrococcus radiodurans. J Bacteriol. 1969 Feb;97(2):647–652. [PMC free article] [PubMed]
  • Moseley BE, Setlow JK. Transformation in Micrococcus radiodurans and the ultraviolet sensitivity of its transforming DNA. Proc Natl Acad Sci U S A. 1968 Sep;61(1):176–183. [PMC free article] [PubMed]
  • Okubo S, Romig WR. Comparison of ultraviolet sensitivity of Bacillus subtilis bacteriophage SPO2 and its infectious DNA. J Mol Biol. 1965 Nov;14(1):130–142. [PubMed]
  • Reiter H, Strauss B. Repair of damage induced by a monofunctional alkylating agent in a transformable, ultraviolet-sensitive strain of Bacillus subtilis. J Mol Biol. 1965 Nov;14(1):179–194. [PubMed]
  • Setlow JK, Brown DC, Boling ME, Mattingly A, Gordon MP. Repair of deoxyribonucleic acid in Haemophilus influenzae. I. X-ray sensitivity of ultraviolet-sensitive mutants and their behavior as hosts to ultraviolet-irradiated bacteriophage and transforming deoxyribonucleic acid. J Bacteriol. 1968 Feb;95(2):546–558. [PMC free article] [PubMed]
  • Witkin EM. Ultraviolet-induced mutation and DNA repair. Annu Rev Microbiol. 1969;23:487–514. [PubMed]

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