Antitumour agent coralyne: A guanine-cytosine specific DNA-binding alkaloid

摘要

The base and sequence specificity of coralyne-DNA interaction were investigated by spectrophotometric, spectrofluorimetric, circular dichroic, thermal melting and viscometric studies. The strong binding of this alkaloid to various natural and synthetic DNAs was characterized by remarkably large changes of hypochromism and bathochromism in the absorption bands, quenching of steady state fluorescence intensity, decrease in quantum yield, perturbations In circular dichroic spectrum, stabilization of DNA against thermal denaturation and increase in contour length of sonicated rod-like duplex DNA, Binding of coralyne to various DNAs was dependent upon the base pair composition and sequence of DNA, being larger for GC-rich DNA and alternating GC polymer as observed front the above techniques. These studies demonstrate the GC base pair specificity in the intercalative DNA binding of coralyne. [References: 28]