Induction of oxygen-dependent lethal damage by monochromatic UVB (313 nm) radiation: strand breakage, repair and cell death

Journal Article · Fri Dec 31 23:00:00 EST 1982 · Carcinogenesis (N.Y.); (United States)

DOI:https://doi.org/10.1093/carcin/4.4.375· OSTI ID:5301220

Miguel, A G ^[1]; Tyrrell, R M ^[2]

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1. Rio de Janeiro Univ. (Brazil). Inst. de Biofisica
2. Institut Suisse de Recherches Experimentales sur le Cancer, Lausanne

The action of UV-B (313 nm) radiation in cellular inactivation and induction and repair of DNA strand breaks were studied in a repair proficient strain and three repair deficient strains (polA, recA, uvrA) of Escherichia coli K-12. Although the induction of breaks was linear in purified T/sub 4/ DNA and the polA strain, simultaneous induction and repair of breaks were observed in the uvrA, recA and repair proficient strains at doses <5 x 10/sup 4/ Jm/sup -2/. The final rates of induction in these strains were 1 x 10/sup -4/, 7.5 x 10/sup -5/ and 7.5 x 10/sup -5/ breaks/2.5 x 10/sup 9/ daltons/Jm/sup -2/, respectively. A highly efficient polA-dependent repair occurring at 0/sup 0/C in minimal buffer and a second slower type of repair occurring at 31/sup 0/C in the polA strain were detected. Oxygen dependence of cellular inactivation was observed for the polA and repair proficient strains irradiated at 313 nm thus providing biological evidence for an oxygen-dependent lesion involved in lethality in the short wavelength range of the solar u.v. The lower hypoxic break induction rates of the polA and the repair proficient strains, indicate oxygen-enhanced DNA breakage by 313 nm radiation.

• OSTI ID: 5301220
• Journal Information: Carcinogenesis (N.Y.); (United States), Journal Name: Carcinogenesis (N.Y.); (United States) Vol. 4:4; ISSN CRNGD
• Country of Publication: United States
• Language: English

Related Subjects

560112* -- Radiation Effects on Biochemicals-- In Microorganisms-- (-1987)
63 RADIATION, THERMAL, AND OTHER ENVIRON. POLLUTANT EFFECTS ON LIVING ORGS. AND BIOL. MAT.
BACTERIA
BIOLOGICAL EFFECTS
BIOLOGICAL RADIATION EFFECTS
BIOLOGICAL RECOVERY
BIOLOGICAL REPAIR
CELL KILLING
DNA
ELECTROMAGNETIC RADIATION
ESCHERICHIA COLI
MICROORGANISMS
NEAR ULTRAVIOLET RADIATION
NUCLEIC ACIDS
ORGANIC COMPOUNDS
RADIATION EFFECTS
RADIATIONS
RECOVERY
REPAIR
RESPONSE MODIFYING FACTORS
STRAND BREAKS
SURVIVAL CURVES
ULTRAVIOLET RADIATION