Basic aspects of radiation action on microorganisms. Progress report, April 1, 1976--June 30, 1977. [Escherichia coli, Pseudomonas, lambda phage, gamma and uv radiation]

Technical Report · Fri Jul 01 04:00:00 EDT 1977

OSTI ID:7294542

Pollard, E C

Ultraviolet mutagenesis follows a relation, part of which is an induction process, very similar to the induction process for induced radioresistance and induced inhibition of postirradiation DNA degradation. The repair of single-strand breaks produced by gamma rays takes place more rapidly than does postirradiation DNA degradation. Repaired DNA is degraded and there is good repair of single-strand breaks in lex cells followed by degradation of the repaired DNA. The signal for the start of radiation-induced DNA degradation is probably NOT single-strand breaks. The dose-response relation for lambda induction requires more dose and has kinetics different from those for the induction of other phenomena. We find no evidence of induced radioresistance in two lambda lysogens of E. coli. There IS induced radioresistance if the lysogens are of induction-minus phage. UV given at -79/sup 0/C, which is believed to produce DNA-protein crosslinks, is an excellent inducer and also a good mutagen. Near UV produces lesions which are recognized by the induced repair system. At the same time, near UV also damages the induced repair system. There is increased mutagenesis at 313 nm wavelength following induction by ionizing radiation. It is likely that the phenomenon of induced radioresistance can be produced in one of several nuclei and that this one can give rise to a resistant colony. We find no evidence of induced radioresistance, nor of inhibition of postirradiation DNA degradation, in two strains of Pseudomonas.

• Research Organization: Pennsylvania State Univ., University Park (USA)
• OSTI ID: 7294542
• Report Number(s): COO-2362-26
• Country of Publication: United States
• Language: English

Related Subjects

560131* -- Radiation Effects on Microorganisms-- Basic Studies-- (-1987)
63 RADIATION, THERMAL, AND OTHER ENVIRON. POLLUTANT EFFECTS ON LIVING ORGS. AND BIOL. MAT.
BACTERIA
BACTERIOPHAGES
BIOLOGICAL EFFECTS
BIOLOGICAL RADIATION EFFECTS
BIOLOGICAL RECOVERY
BIOLOGICAL REPAIR
DNA
DOSE-RESPONSE RELATIONSHIPS
ELECTROMAGNETIC RADIATION
ESCHERICHIA COLI
GAMMA RADIATION
IONIZING RADIATIONS
MICROORGANISMS
MUTAGENESIS
MUTATIONS
NUCLEIC ACIDS
ORGANIC COMPOUNDS
PARASITES
PSEUDOMONAS
RADIATION EFFECTS
RADIATIONS
RADIOINDUCTION
RADIOSENSITIVITY
REPAIR
STRAND BREAKS
ULTRAVIOLET RADIATION
VIRUSES