Structure of a hydroxyl radical induced DNA-protein cross-link involving thymine and tyrosine in nucleohistone

Journal Article · Tue Apr 18 04:00:00 EDT 1989 · Biochemistry; (USA)

DOI:https://doi.org/10.1021/bi00434a071· OSTI ID:5670817

Dizdaroglu, M; Gajewski, E; Reddy, P; Margolis, S A ^[1]

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1. National Institute of Standards and Technology, Gaithersburg, MD (USA)

Hydroxyl radical induced formation of a DNA-protein cross-link involving thymine and tyrosine in nucleohistone is described. Hydroxyl radicals were generated in N{sub 2}O-saturated aqueous solution by ionizing radiation. Samples of nucleohistone were hydrolyzed with HCl and trimethylsilylated. Analysis of irradiated samples by gas chromatography-mass spectrometry with selected-ion monitoring showed the presence of a thymine-tyrosine cross-link on the basis of typical fragment ions from the previously known mass spectrum of its trimethylsilyl derivative. The yield of this DNA-protein cross-link in nucleohistone was measured at incrementing doses of radiation and found to be a linear function of radiation dose between 14 and 300 Gy (J{center dot}kg{sup {minus}1}). This yield amounted to 0.003 {mu}mol{center dot}J{sup {minus}1}. The mechanism of formation of this DNA-protein cross-link is thought to result from H atom abstraction by hydroxyl radicals from the methyl group of thymine followed by the addition of the resultant thymine radical to the carbon 3 position of the tyrosine ring and subsequent oxidation of the adduct radical.

• OSTI ID: 5670817
• Journal Information: Biochemistry; (USA), Journal Name: Biochemistry; (USA) Vol. 28:8; ISSN 0006-2960; ISSN BICHA
• Country of Publication: United States
• Language: English

Related Subjects

550602* -- Medicine-- External Radiation in Diagnostics-- (1980-)
62 RADIOLOGY AND NUCLEAR MEDICINE
AMINO ACIDS
AQUEOUS SOLUTIONS
AZINES
BETA DECAY RADIOISOTOPES
BETA-MINUS DECAY RADIOISOTOPES
BIOLOGICAL EFFECTS
BIOLOGICAL RADIATION EFFECTS
CARBOXYLIC ACIDS
CHALCOGENIDES
CHEMICAL REACTIONS
CHROMATOGRAPHY
COBALT 60
COBALT ISOTOPES
CROSS-LINKING
DISPERSIONS
DNA
DOSES
ELECTROMAGNETIC RADIATION
ELECTROPHORESIS
GAMMA RADIATION
GAS CHROMATOGRAPHY
HETEROCYCLIC COMPOUNDS
HISTONES
HYDROXY ACIDS
HYDROXY COMPOUNDS
HYDROXYL RADICALS
INTERMEDIATE MASS NUCLEI
INTERNAL CONVERSION RADIOISOTOPES
IONIZING RADIATIONS
ISOMERIC TRANSITION ISOTOPES
ISOTOPES
MASS SPECTROSCOPY
MINUTES LIVING RADIOISOTOPES
MIXTURES
NITROGEN COMPOUNDS
NITROGEN DIOXIDE
NITROGEN OXIDES
NUCLEI
NUCLEIC ACIDS
NUCLEOPROTEINS
ODD-ODD NUCLEI
ORGANIC ACIDS
ORGANIC COMPOUNDS
ORGANIC NITROGEN COMPOUNDS
OXIDES
OXYGEN COMPOUNDS
POLYMERIZATION
PROTEINS
PYRIMIDINES
RADIATION DOSES
RADIATION EFFECTS
RADIATIONS
RADICALS
RADIOISOTOPES
SEPARATION PROCESSES
SOLUTIONS
SPECTROSCOPY
THYMINE
TYROSINE
URACILS
YEARS LIVING RADIOISOT