Electron microscopic visualization of DNA single strand breaks.
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.
Jungblut
H D
HD
Physiologisch-Chemisches Institut, University and Academy of Science and Literature, Mainz, F.R.G.
Stüber
J J
JJ
Zahn
R K
RK
D000818:Animals; D001564:Benzo(a)pyrene / Q000633:toxicity; D001580:Benzopyrenes / Q000633:toxicity; D001710:Biotin; D002460:Cell Line; D004249:DNA Damage; D004256:DNA Polymerase I; D004260:DNA Repair; D004261:DNA Replication; D004305:Dose-Response Relationship, Drug; D005293:Ferritins; D051379:Mice; D008854:Microscopy, Electron / Q000379:methods*
D001580:Benzopyrenes; D001564:Benzo(a)pyrene; C026487:benzo(e)pyrene; D001710:Biotin; D005293:Ferritins; D004256:DNA Polymerase I