Dukhopel'nykov Y. Molecular mechanism of interaction of new actinocin antibiotics with nucleic acid matrices

Сomplexes of actinocin derivatives (Act II - V) with DNA and poly(rC). To investigate structure and stability of complexes of Act II - V with DNA and poly(rC). Methods of research are the IR-spectroscopy, the piezogravimetry and the differential scanning calorimetry. It is shown that complex poly(rC)-ActIII forms by outside type of binding. It is found that the melting temperature and enthalpy of poly(rC) in the presence of ActIII is lower than pure poly(rC). The interaction of actinocine derivatives with DNA occures on the intercalation type. Ligand ActII forms additional bonds with shugar-phosphate backbone. It is found that the melting temperature and enthalpy of DNA in the presence of actinocin derivatives increases. Maximum value of the melting temperature and enthalpy was demonstrated by the complex DNA - Act II. The interaction with hydrated environment sufficiently (up to 60-80%) stabilize the helical structure. Sphere f use is the biophysics and medical physics