title: Design of amphiphilic oligopeptides as models for fine tuning peptide assembly with plasmid DNA.
abstract: We discuss the design of novel amphiphilic oligopeptides with hydrophobic and cationic amino acids to serve as models to understand peptide-DNA assembly. Biophysical and thermodynamic characterization of interaction of these amphiphilic peptides with plasmid DNA is presented. Peptides with at least +4 charges favor stable complex formation. Surface potential is dependent on the type of hydrophobic amino acid for a certain charge. Thermodynamically it is a spontaneous interaction between most of the peptides and plasmid DNA. Lys(7) and Tyr peptides with +4/+5 charges indicate cooperative binding with pDNA without saturation of interaction while Val(2)-Gly-Lys(4), Val-Gly-Lys(5), and Phe-Gly-Lys(5) lead to saturation of interaction indicating condensed pDNA within the range of N/Ps studied. We show that the biophysical properties of DNA-peptide complexes could be modulated by design and the peptides presented here could be used as building blocks for creating DNA-peptide complexes for various biomedical applications, mainly nucleic acid delivery.
authors.affiliation: Department of Pharmaceutical Sciences, University of the Sciences in Philadelphia.
authors.forename: Geetha N
authors.initials: GN
authors.lastname: Goparaju
authors.forename: Pardeep K
authors.initials: PK
authors.lastname: Gupta
mesh_terms: D004247:DNA / Q000737:chemistry*; D015195:Drug Design; D009842:Oligopeptides / Q000737:chemistry*; D010957:Plasmids; D013816:Thermodynamics
chemical_list: D009842:Oligopeptides; D004247:DNA