Oxidative DNA strand scission induced by peptides.
Cellular oxidative stress promotes chemical reactions causing damage to DNA, proteins, and membranes. Here, we describe experiments indicating that reactive oxygen species, in addition to degrading polypeptides and polynucleotides through direct reactions, can also promote damaging biomolecular cross reactivity by converting protein residues into peroxides that cleave the DNA backbone. The studies reported show that a variety of residues induce strand scission upon oxidation, and hydrogen abstraction occurring at the DNA backbone is responsible for the damage. The observation of peptide-promoted DNA damage suggests that crossreactions within protein/DNA complexes should be considered as a significant cause of the toxicity of reactive oxygen species.
Merkert Chemistry Center, Boston College, Chestnut Hill, MA 02467, USA.
Erin G
EG
Prestwich
Marc D
MD
Roy
Jennifer
J
Rego
Shana O
SO
Kelley
D000596:Amino Acids / Q000737:chemistry / Q000494:pharmacology; D001483:Base Sequence; D004247:DNA / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism*; D015394:Molecular Structure; D010084:Oxidation-Reduction / Q000187:drug effects; D010455:Peptides / Q000737:chemistry / Q000494:pharmacology*
D000596:Amino Acids; D010455:Peptides; D004247:DNA