Interaction of antitumor drug aclacinomycin-A with DNA and its specific sequence site

Through UV and fluorescence spectrophotometries, the interaction of aclacinomycin-A (ACM-A) with DNA and its specific sequence have been investigated with the aid of circular dichroism spectrophotometry and differential pulse voltammetry method. The results demonstrated that ACM-A was capable of intercalating DNA double helix, the π-π electronic overlapping between π-electrons of ACM-A and base pair of DNA stabilized the ACM-A-DNA adduct, and through electrostatic interaction, the trisaccharide interacted with the minor groove of DNA owing to an amino group at C(3′). Electrochemical and spectroelectrochemical studies revealed that the original form of ACM-A had higher affinity for DNA than the reduction form in which the trisaccharide group at C(7) was lost. According to the results obtained in this paper, ACM-A showed preference for AT base pairs of the deoxyribonucleic acid duplex, and it was apt to interact with cytosine and thymine rather than the adenine of oligonucleotide.