Probing of DNA structure with osmium tetroxide,2,2'-bipyridine. Adduct-specific antibodies.
Antibodies against DNA modified with a single-strand selective probe, OsO4 in complex with 2,2'-bipyridine (Os,bipy), were raised in rabbits. These antibodies were fractionated using affinity column chromatography and fractions S89-II and S89-III characterized as highly specific for DNA-Os,bipy adduct with no cross reactivity to at least 1000-fold excess of unmodified DNA, RNA and Os,bipy-modified and unmodified proteins. Cross-reactivity to Os,bipy-modified RNA was very small. S89-II showed no cross-reactivity to DNA modified with OsO4 complexed with tetramethylethylenediamine or with bathophenanthroline disulphonic acid and to DNA oxidized with KMnO4. It cross-reacted, however, with DNA modified with OsO4,1,10-phenanthroline complex. The limit of detection of immunodot-blot analysis of extensively Os,bipy-modified DNA was below 0.5 pg. Small extent of Os,bipy-modification of supercoiled and linearized plasmids can be detected by DNA gel retardation and immunoblotting techniques. E. coli cells contain DNA regions in which bases are accessible to the single-strand selective probe.
Kuderová-Krejcová
A
A
Institute of Biophysics, Czechoslovak Academy of Sciences, Brno.
Poverenny
A M
AM
Palecek
E
E
D015082:2,2'-Dipyridyl / Q000737:chemistry*; D002846:Chromatography, Affinity; D002875:Chromosomes / Q000737:chemistry; D003429:Cross Reactions; D004278:DNA, Superhelical / Q000737:chemistry*; D004586:Electrophoresis; D004797:Enzyme-Linked Immunosorbent Assay; D004926:Escherichia coli / Q000235:genetics; D015335:Molecular Probes / Q000737:chemistry*; D009690:Nucleic Acid Conformation; D009993:Osmium Tetroxide / Q000737:chemistry*; D010957:Plasmids / Q000235:genetics
D004278:DNA, Superhelical; D015335:Molecular Probes; D015082:2,2'-Dipyridyl; D009993:Osmium Tetroxide