Interaction of chelerythrine choloride in acid buffer with calf-thymus DNA

The binding of chelerythrine (CHE) iminium to calf-thymus (CT) DNA is characterized by hypochromism and bathochromism in the absorption band, enhancement of fluorescence intensity, increase in fluorescence polarization, and the perturbation of the CD spectra of DNA. These changes are characteristic of intercalation. Scatchard plots constructed from fluorescence titration data gave a binding constant of 5.77 x 10(5) and a binding site size of 3,4 base pairs at 25 degrees C. The intercalative interaction is exothermic with a Van't Hoff enthalpy of -33.7 kJ/mol. In addition, Delta G =-32.9 kJ/mol, and AS =-2.9 J/mol/K. The intercalation of CHE into the DNA helix is enthalpy-driven.http://gateway.webofknowledge.com/gateway/Gateway.cgi?GWVersion=2&SrcApp=PARTNER_APP&SrcAuth=LinksAMR&KeyUT=WOS:000238804200035&DestLinkType=FullRecord&DestApp=ALL_WOS&UsrCustomerID=8e1609b174ce4e31116a60747a720701Chemistry, MultidisciplinarySCI(E)中国科技核心期刊(ISTIC)10ARTICLE5691-6941