title: Solid phase synthesis of peptide-selenoesters.
abstract: The synthesis of proteins by native chemical ligation greatly enhances the application of chemistry to complex molecules such as proteins. The essential building blocks for this approach traditionally have been peptide-thioester segments that are linked chemoselectively in consecutive reactions. By using peptide selenoesters instead of thioesters, the ligation rate can be significantly accelerated permitting couplings at difficult sites and potentially enabling new ligation strategies. To facilitate the routine synthesis of selenoester peptides, a general and straightforward procedure has been developed that generates a suitably functionalized resin from which the desired selenoester peptide can be readily synthesized. This simple approach utilizes readily available and cheap chemical agents and enables production of peptide selenoesters of excellent quality in short time and with high recovery. In addition, the stability of peptide selenoesters was examined under different native chemical ligation conditions and compared to thioesters. Selenoesters are slightly more reactive and more susceptible to hydrolysis and aminolysis than thioesters but sufficiently stable under mildly acidic conditions (pH 6.5). Under these conditions, rapid selenoester-mediated ligation is kinetically favoured.
authors.affiliation: Division of Chemistry and Structural Biology, Institute for Molecular Bioscience, The University of Queensland, St Lucia, Brisbane, Queensland 4072, Australia.
authors.forename: Artin
authors.initials: A
authors.lastname: Ghassemian
authors.forename: Xavier
authors.initials: X
authors.lastname: Vila-Farrés
authors.forename: Paul F
authors.initials: PF
authors.lastname: Alewood
authors.forename: Thomas
authors.initials: T
authors.lastname: Durek
mesh_terms: D004952:Esters / Q000138:chemical synthesis* / Q000737:chemistry; D016566:Organoselenium Compounds / Q000138:chemical synthesis* / Q000737:chemistry; D010455:Peptides / Q000138:chemical synthesis* / Q000737:chemistry
chemical_list: D004952:Esters; D016566:Organoselenium Compounds; D010455:Peptides