title: Synthesis of Peptide-oligonucleotide conjugates by Diels-Alder cycloaddition in water.
abstract: Peptide-oligonucleotide conjugates incorporating all the nucleobases and trifunctional amino acids are obtained by Diels-Alder reaction between diene-modified oligonucleotides (2'-deoxyribo- or ribo-) and malemide-derivatized peptides. Both reagents are easily synthesized by on-column derivatization of the corresponding peptides and oligonucleotides. The cycloaddition reaction is carried out under mild conditions, in aqueous solution at 37 degrees C, affording the desired peptide-oligonucleotide conjugate with high purity and yield. The speed of the reaction depends on the size and composition of both reagents, but it is accelerated by the presence of positively charged amino acids in the peptide fragment. However, a small excess of maleimide-derivatized peptide may be required in some cases to complete the reaction within 8 to 10 hr.
authors.affiliation: Institut de Biomedicina de la Universitat de Barcelona, Barcelona, Spain.
authors.forename: Vicente
authors.initials: V
authors.lastname: Marchán
authors.forename: Anna
authors.initials: A
authors.lastname: Grandas
mesh_terms: D002851:Chromatography, High Pressure Liquid; D003500:Cyclization; D009841:Oligonucleotides / Q000138:chemical synthesis* / Q000737:chemistry; D010455:Peptides / Q000138:chemical synthesis* / Q000737:chemistry; D021241:Spectrometry, Mass, Electrospray Ionization; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization; D014867:Water / Q000737:chemistry*
chemical_list: D009841:Oligonucleotides; D010455:Peptides; D014867:Water