title: Physico-chemical investigation of the mode of binding of the alkaloids 5,6-dihydroflavopereirine and sempervirine with DNA.
abstract: The mode of binding of 5,6-dihydroflavopereirine and sempervirine to DNA has been investigated by absorption spectrophotometry, circular and electric linear dichroism, fluorescence and fluorescence polarization, viscosity increase of sonicated linear DNA and circular DNA unwinding. Although the spectroscopic properties of both compounds bound to DNA resembled those reported in our previous study of DNA complexes with two other alkaloids, and observed with planar intercalating compounds, only sempervirine was able to unwind circular DNA. The latter drug however showed signs characteristic of aggregation at the surface of the polyion. The differences between the behaviours of the four alkaloids so far investigated by us are interpreted on the basis of different extent of penetration of the chromophore ring into the DNA helix.
mesh_terms: D000470:Alkaloids; D000972:Antineoplastic Agents, Phytogenic; D002243:Carbolines; D055598:Chemical Phenomena; D002621:Chemistry; D004247:DNA; D004270:DNA, Circular; D007211:Indoles; D009690:Nucleic Acid Conformation; D011807:Quinolizines; D046948:Secologanin Tryptamine Alkaloids; D013050:Spectrometry, Fluorescence; D013056:Spectrophotometry, Ultraviolet; D014783:Viscosity
chemical_list: D000470:Alkaloids; D000972:Antineoplastic Agents, Phytogenic; D002243:Carbolines; D004270:DNA, Circular; D007211:Indoles; D011807:Quinolizines; D046948:Secologanin Tryptamine Alkaloids; C041335:5,6-dihydroflavopereirine; D004247:DNA; C009234:sempervirine