Synthesis of a l-lysine-based alternate alpha,epsilon-peptide: a novel linear polycation with nucleic acids-binding ability

A novel nucleic acid compaction device based on a positivelycharged alpha,epsilonpolyllysine was realized for the first time. The polycationic peptide was obtained by assembling Fmoc and Boc orthogonally protected llysine monomers by solid phase synthesis. The route to the novel polycation is very fast and convenient because it allows for the obtainment of the desired product in few synthetic steps exclusively employing Fmoc chemistry. The purification of the polyamino acid was performed easily by RPHPLC on C18 stationary phase while ESIMS analysis confirmed the identity of the novel basic molecule. The structural characteristics of the novel watersoluble peptide, as well as the interaction with deoxyribonucleic acid (DNA) and ribonucleic acid (RNA) have been investigated by circular dichroism (CD) and ultraviolet (UV) spectroscopy.