Understanding the Binding Mechanism of a Pyrazino[1,2-a]indole Derivative with Calf Thymus DNA

This work was focused on understanding the interaction mechanism of pyrazino[1,2-a]indole derivative in calf thymus DNA (ctDNA) using various spectroscopy and computational techniques. The UV-Vis absorption result shows that the binding interaction of pyrazino[1,2-a]indole derivative in ctDNA complex may be in the non -covalent form and the binding associate constant K-a value was estimated 7.06x10(3)Lmol(-1) at 297K. The fluorescence emission spectroscopy analysis suggested that pyrazino[1,2-a]indole derivative quenching mechanism in ctDNA mainly due to the static nature and thermodynamical parameter analysis implied the binding of pyrazino[1,2-a]indole derivative in ctDNA mainly due to hydrophobic force. Forster resonance energy transfer analysis was also calculated and the r=2.1nm. Circular dichroism spectra conclude that there is a change in the secondary structural region of ctDNA due to an interaction with pyrazino[1,2-a]indole derivative. Together with the molecular docking studies, hydrophobic nature of the interaction of pyrazino[1,2-a]indole derivative with ctDNA might be deduced.