Study intermolecular interations of short synthetic peptides with various structures of dna

Abstract

consist of a brief overview of diverse canonical and non-canonical conformations of DNA along with its biological significance. This chapter covers the detailed structural information about telomeric and oncogeneic G-quadruplex conformation and up-to-date review of the literatures. At the end of chapter, the structural features of peptides and the advantages of using peptide as the DNA targeting ligand have been highlighted. Chapter 2 presents the reagents and experimental procedures adopted to perform the entire works. Chapter 3 describes the synthesis, self-association and DNA binding studies of an aromatic tripeptide H-Phe-Phe-Phe-OH (FFF). The peptide adopts and#946;and#61485;sheet conformation both in solid state and in solution. In aqueous solution, FFF self-assembles to form nanostructured aggregates. Interactions of this peptide with model dsDNA (ct-DNA) have been studied using various biophysical techniques. The association constant, calculated from UV and fluorescence spectroscopic data, is in the order of 103 M-1 which is consistent with the external binding mode. ITC data also substantiate the spectroscopic finding. Fluorescence intercalator displacement (FID) assay, iodide quenching study, viscosity measurement and thermal denaturation study of DNA further confirm the groove binding mode of peptide, FFF with ct-DNA newline