Kinetic flow dichroism studies indicate that the (+) enantiomer of 7β, 8α-dihydroxy-9α, 10α-epoxy-7,8,9,10-tetrahydrobenzo(a)pyrene physically bound at intercalative-type sites in double-stranded DNA undergoes covalent binding reactions to form adducts at external binding sites. The conformation of the non-covalent complex derived from the (-) stereoisomer is also intercalative in nature, but the conformations of the covalent adducts are heterogeneous and are characterized by both intercalative-type and external conformations. It is suggested that the distinctly higher biological activity of the (+) enantiomer relative to the activity of the (-) enantiomer may be related to the preponderance of 7,8,9-triol benzo(a)pyrene residues covalently linked to deoxyguanine and located at external binding sites in the DNA adducts.
|Original language||English (US)|
|Number of pages||7|
|Journal||Biochemical and Biophysical Research Communications|
|State||Published - Jul 18 1984|
ASJC Scopus subject areas
- Molecular Biology
- Cell Biology