Photoreactivation of Pyrimidine Dimers in the DNA of Normal and Xeroderma Pigmentosum Cells

Betsy M. Sutherland, Rowena Oliver, Charles O. Fuselier, John C. Sutherland

Research output: Contribution to journalArticlepeer-review

26 Scopus citations


Photoproducts formed in the DNA of human cells irradiated with ultraviolet light (uv) were identified as cyclobutyl pyrimidine dimers by their chromatographic mobility, reversibility to monomers upon short wavelength uv irradiation, and comparison of the kinetics of this monomerization with that of authentic cis-syn thymine-thymine dimers prepared by irradiation of thymine in ice. The level of cellular photoreactivation of these dimers reflects the level of photoreactivating enzyme measured in cell extracts. Action spectra for cellular dimer photoreactivation in the xeroderma pigmentosum line XP12BE agree in range (300 nm to at least 577 nm) and maximum (near 400 nm) with that for photoreactivation by purified human photoreactivating enzyme. Normal human cells can also photoreactivate dimers in their DNA. The action spectrum for the cellular monomerization of dimers is similar to that for photoreactivation by the photoreactivating enzyme in extracts of normal human fibroblasts.

Original languageEnglish (US)
Pages (from-to)402-406
Number of pages5
Issue number2
StatePublished - Jan 1 1976
Externally publishedYes

ASJC Scopus subject areas

  • Biochemistry


Dive into the research topics of 'Photoreactivation of Pyrimidine Dimers in the DNA of Normal and Xeroderma Pigmentosum Cells'. Together they form a unique fingerprint.

Cite this