title: Synthesis of homogeneous glycopeptides and their utility as DNA condensing agents.
abstract: Two glycopeptides were synthesized by attaching purified glycosylamines (N-glycans) to a 20 amino acid peptide. Triantennary and Man9 Boc-tyrosinamide N-glycans were treated with trifluoroacetic acid to remove the Boc group and expose a tyrosinamide amine. The amine group was coupled with iodoacetic acid to produce N-iodoacetyl-oligosaccharides. These were reacted with the sulfhydryl group of a cysteine-containing peptide (CWK18), resulting in the formation of glycopeptides in good yield that were characterized by 1H NMR and ESIMS. Both glycopeptides were able to bind to plasmid DNA and form DNA condensates of approximately 110 nm mean diameter with zeta potential of +31 mV. The resulting homogeneous glycopeptide DNA condensates will be valuable as receptor-mediated gene-delivery agents.
authors.affiliation: Division of Pharmaceutics, College of Pharmacy, University of Michigan, Ann Arbor 48109-1065, USA.
authors.forename: W T
authors.initials: WT
authors.lastname: Collard
authors.forename: D L
authors.initials: DL
authors.lastname: Evers
authors.forename: D L
authors.initials: DL
authors.lastname: McKenzie
authors.forename: K G
authors.initials: KG
authors.lastname: Rice
mesh_terms: D002240:Carbohydrate Sequence; D002851:Chromatography, High Pressure Liquid; D003102:Colloids / Q000737:chemistry; D004247:DNA / Q000378:metabolism*; D018014:Gene Transfer Techniques; D006020:Glycopeptides / Q000138:chemical synthesis* / Q000494:pharmacology*; D009682:Magnetic Resonance Spectroscopy; D008956:Models, Chemical; D008969:Molecular Sequence Data; D010455:Peptides / Q000138:chemical synthesis; D011134:Polysaccharides / Q000737:chemistry; D013997:Time Factors
chemical_list: D003102:Colloids; D006020:Glycopeptides; D010455:Peptides; D011134:Polysaccharides; D004247:DNA