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

Journal Article · Sat Jan 01 04:00:00 EST 1983 · Carcinogenesis (N.Y.); (United States)

DOI:https://doi.org/10.1093/carcin/4.4.375· OSTI ID:5849794

Miguel, A G; Tyrrell, R M

The action of 313 nm radiation in cellular inactivation (biological measurements) and induction and repair of DNA strand breaks (physical measurements) 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 T4DNA (6.3 X 10(-4) breaks/2.5 X 10(9) daltons/Jm-2) and the polA strain (4 X 10(-4) breaks/2.5 X 10(9) daltons/Jm-2), simultaneous induction and repair of breaks were observed in the uvrA, recA and repair proficient strains at doses less than 5 X 10(4) Jm-2. The final rates of induction in these strains were 1 X 10(-4), 7.5 X 10(-5) and 7.5 X 10(-5) breaks/2.5 X 10(9) daltons/Jm-2, respectively. A highly efficient polA-dependent repair occurring at 0 degree C in minimal buffer and a second slower type of repair occurring at 31 degrees 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 (1.6 X 10(-4) breaks/2.5 X 10(9) daltons/Jm-2) and the repair proficient (3.6 X 10(-5) breaks/2.5 X 10(9) daltons/Jm-2) strains, indicate oxygen-enhanced DNA breakage by 313 nm radiation.

• Research Organization: Instituto de Biofisica, Universidade Federal do Rio de Janeiro, Brazil
• OSTI ID: 5849794
• 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
DNA
ELECTROMAGNETIC RADIATION
ESCHERICHIA COLI
MICROORGANISMS
NUCLEIC ACIDS
ORGANIC COMPOUNDS
RADIATION EFFECTS
RADIATIONS
RADIOINDUCTION
RECOVERY
REPAIR
STRAND BREAKS
ULTRAVIOLET RADIATION