DRUG-BINDING TO DNA - OBSERVATION OF THE DRUG-DNA HYDROGEN-BOND-STRETCHING MODES OF NETROPSIN BOUND TO DNA VIA RAMAN-SPECTROSCOPY

Raman scattering and normal mode calculations have been used to study the low frequency vibrations of NaDNA, netropsin, and the NaDNA.netrop sin complex. Vibrational modes at about 60 and 180 cm(-1) are observed from the DNA.netropsin complex but not from either pure DNA or pure n etropsin. Theoretical calculations show that these are stretching mode s of the hydrogen bonds connecting netropsin to DNA. Identification of these modes in this and other systems may facilitate the study of bio molecule ligand binding dynamics.