Binding of radiation-induced phenylalanine radicals to DNA: influence on the biological activity of the DNA and on its sensitivity to the induction of breaks by gamma rays

Technical Report · Sat Nov 01 00:00:00 EST 1975

OSTI ID:7304942

Vanderschans, G P; Vanrijn, C J.S.; Bleichrodt, J F

When an aqueous solution of double-stranded deoxyribonucleic acid (DNA) of bacteriophage PM2 containing phenylalanine and saturated with N2O is irradiated with gamma rays, radiation induced phenylalanine radicals are bound covalently. Under the conditions used about 25 phenylalanine molecules may be bound per lethal hit. Also for single-stranded PM2 DNA most of the phenylalanine radicals bound are nonlethal. Evidence is presented that in double-stranded DNA an appreciable fraction of the single-strand breaks is induced by phenylalanine radicals. Radiation products of phenylalanine and the phenylalanine bound to the DNA decrease the sensitivity of the DNA to the induction of single-strand breaks. There are indications that the high efficiency of protection by radiation products of phenylalanine is due to their positive charge, which will result in a relatively high concentration of these compounds in the vicinity of the negatively charged DNA molecules. (Author) (GRA)

• Research Organization: Rijksverdedigingsorganisatie TNO, Rijswijk (Netherlands). Medisch Biologisch Lab. TNO
• OSTI ID: 7304942
• Report Number(s): N-76-31888; MBL-1975-27; TDCK-67114
• Country of Publication: United States
• Language: English

Related Subjects

63 RADIATION, THERMAL, AND OTHER ENVIRON. POLLUTANT EFFECTS ON LIVING ORGS. AND BIOL. MAT.
DNA
STRAND BREAKS
PHENYLALANINE
RADIOSENSITIVITY EFFECTS
AQUEOUS SOLUTIONS
BACTERIOPHAGES
BIOLOGICAL RADIATION EFFECTS
GAMMA RADIATION
IRRADIATION
RADICALS
AMINO ACIDS
BIOLOGICAL EFFECTS
CARBOXYLIC ACIDS
DISPERSIONS
ELECTROMAGNETIC RADIATION
IONIZING RADIATIONS
MICROORGANISMS
MIXTURES
NUCLEIC ACIDS
ORGANIC ACIDS
ORGANIC COMPOUNDS
PARASITES
RADIATION EFFECTS
RADIATIONS
SOLUTIONS
VIRUSES
560111* - Radiation Effects on Biochemicals- In Vitro- (-1987)