Binding of Bisbenzamidines with AT Rich DNA: A Thermodynamic Study

• Main Author: Kilpatrick, Nancy A
• Format: Others
• Published: Digital Archive @ GSU 2011
• Subjects: Binding; DNA; Pentamidine; Minor groove binders; Thermodynamics; ITC
• Online Access: http://digitalarchive.gsu.edu/chemistry_theses/41; http://digitalarchive.gsu.edu/cgi/viewcontent.cgi?article=1040&context=chemistry_theses

Diamidines are small molecules that generally possess antiparasitic properties and bind preferentially to the minor groove of AT rich DNA. With the goal of getting a better understanding of the thermodynamic driving forces and binding affinities, a series of pentamidine analogs were investigated with various AT rich DNA by ITC, UV-Vis and fluorescence spectroscopic methods. Findings suggest that the substitution of the linker oxygen of pentamidine to a nitrogen slightly improves the binding affinity. All of the investigated compounds are entropically driven at 25 oC with non-alternating AT DNA. Additionally, the increased fluorescence of the nitrogen and sulfur linked analogs will enable future work to be done with fluorescence microscopy to help determine if and where these compounds accumulate in the target organism.