Effects of UV irradiation on the fate of 5-bromodeoxyuridine-substituted bacteriophage T4 DNA

Journal Article · Fri Jul 01 04:00:00 EDT 1983 · J. Virol.; (United States)

OSTI ID:6748636

Restifo, L L; Vogelbacker, H H; Madara, T; Ling, S K; Kozinski, A W

A series of experiments designed to characterize the impact of UV irradiation (260 nm) on 5-bromodeoxyuridine-labeled (heavy) T4 bacteriophage, both before and after infection of Escherichia coli has been carried out. The results have led us to propose a model for a novel mechanism of host-mediated repair synthesis, in which excision of UV-damaged areas is followed by initiation of replication, strand displacement, and a considerable amount of DNA replication. UV irradiation of 5-bromodeoxyuridine-labeled phage results in single-stranded breaks in a linear, dose-dependent manner. This damage does not interfere with injection of the phage genome, but some of the UV-irradiated heavy phage DNA undergoes additional intracellular breakdown (also dose dependent). However, a minority (25%) of the injected parental DNA is protected, maintaining its preinjection size. Furthermore, the extent of the repair replication is greater at higher doses of UV irradiation applied to the heavy phage. This abundant synthesis results ultimately in dispersion of the parental sequences as short stretches in the midst of long segments of newly synthesized progeny DNA. Together, the extensive replication and the resulting distribution pattern of parental sequences, without significant solubilization of parental label, are most consistent with a model of repair synthesis in which the leading strand displaces, rather than ligates to, the encountered 5' end.

• Research Organization: Univ. of Pennsylvania, School of Medicine, Philadelphia
• OSTI ID: 6748636
• Journal Information: J. Virol.; (United States), Journal Name: J. Virol.; (United States) Vol. 47:1; ISSN JOVIA
• Country of Publication: United States
• Language: English

Related Subjects

550700 -- Microbiology
560131* -- Radiation Effects on Microorganisms-- Basic Studies-- (-1987)
59 BASIC BIOLOGICAL SCIENCES
63 RADIATION, THERMAL, AND OTHER ENVIRON. POLLUTANT EFFECTS ON LIVING ORGS. AND BIOL. MAT.
ANTIMETABOLITES
AZINES
BACTERIA
BACTERIOPHAGES
BIOLOGICAL EFFECTS
BIOLOGICAL RADIATION EFFECTS
BIOLOGICAL RECOVERY
BIOLOGICAL REPAIR
BROMOURACILS
BUDR
DNA
DNA REPLICATION
DOSE-RESPONSE RELATIONSHIPS
DRUGS
ELECTROMAGNETIC RADIATION
ESCHERICHIA COLI
EXTREME ULTRAVIOLET RADIATION
HETEROCYCLIC COMPOUNDS
HYDROXY COMPOUNDS
MICROORGANISMS
NUCLEIC ACID REPLICATION
NUCLEIC ACIDS
NUCLEOSIDES
NUCLEOTIDES
ORGANIC BROMINE COMPOUNDS
ORGANIC COMPOUNDS
ORGANIC HALOGEN COMPOUNDS
ORGANIC NITROGEN COMPOUNDS
PARASITES
PYRIMIDINES
RADIATION EFFECTS
RADIATIONS
RADIOINDUCTION
RECOVERY
REPAIR
RIBOSIDES
STRAND BREAKS
ULTRAVIOLET RADIATION
URACILS
VIRUSES