Electron microscopic visualization of DNA single strand breaks.

Chem Biol Interact

Physiologisch-Chemisches Institut, University and Academy of Science and Literature, Mainz, F.R.G.

Published: January 1988

DNA single strand breaks (ssb) have been induced in FLC/C cells in culture. They have been visualized in the electron microscope after decoration with biotin-avidin-ferritin complexes and spreading as monomolecular mixed films. This allowed one to determine the average number of decorated ssbs per unit of DNA length applying straight-forward and simple evaluation methods. This method has been used to investigate the DNA alterations by benzo[a]pyrene (B[a]P) on FLC/C culture cells. Thus a B[a]P-DNA damage curve can be constructed as a regression with a correlation coefficient of r = 0.97, while its isomer benzo[e]pyrene (B[e]P) known to have only low mutagenicity under the same experimental conditions is virtually without effect. The method has further informational potential regarding damage distribution and repair of DNA.

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http://dx.doi.org/10.1016/0009-2797(87)90046-9DOI Listing

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