Complexes of DNA with actinocin-based ampholites were studied by spect
rophotometry, viscosimetry, and dynamic birefringence. The ligand-DNA
binding constants as dependent on pH and ionic strength, and changes i
n the DNA higher structure resulting from complex formation were deter
mined. Models of binding of the ligands to DNA are proposed. It is sho
wn that the zwitterionic compounds do not bind to DNA through intercal
ation. The transition of a compound into a cationic form enables its i
ntercalation into the DNA double helix.