Studies on the Interaction of Poly (I:C) With Cu~(2+)

Abstract

Metal ions play important roles in the biological functions of nucleic adds. It is of importance to the life sciences to investigate the reaction of nucleic acids with metal ions. In the note the interaction of double-stranded helical structure nucleic acid, polyinosinic acid: polycytidylic acid (poly (I:C)) with Cu~(2+) is studied by means of absorption spectra, circular dichroism, fluorescent spectra, melting and cooling curves, acid titration curves and ethidium bromide fluorescent probe. The results show that Cu~(2+) breaks the hydrogen-bonded structure of poly (I: C), and the poly (I: C) untwisting induced by Cu~(2+) is un-reversible and the apparent binding constant of poly (I: C) with Cu~(2+) is 1.23×10~4