title: Copper-induced oligomerization of peptides: a model study.
abstract: In this work, copper-binding of the tetraglycine peptide (Gly-Gly-Gly-Gly) was studied by electrospray ionization mass spectrometry. Experiments were performed under alkaline conditions, in the presence of ethanolamine (pH 10.95). We observed that the presence of copper(II) ions induces the aggregation of the peptide and the formation of copper-bound complexes with higher molecular mass is favored, such as the oligomer complexes [3M+2Cu-3H](+) and [4M+3Cu-5H](+). At 1:1 peptide-copper(II) ion ratio, the singly charged [3M+2Cu-3H](+) oligomer complex is the base peak in the mass spectrum. Metal ion-induced oligomer-ization of neurotoxic peptides is well known in the literature; however, there are very few examples in which such oligomerization was directly observed by mass spectrometry. Our results show that application of short peptides can be useful to study the -mechanism of metal ion binding and metal ion-induced oligomerization of peptides.
authors.affiliation: Research Group of Peptide Chemistry, Hungarian Academy of Sciences, Eötvös L. University, Budapest, Hungary.
authors.forename: Gitta
authors.initials: G
authors.lastname: Schlosser
authors.forename: Raluca
authors.initials: R
authors.lastname: Stefanescu
authors.forename: Michael
authors.initials: M
authors.lastname: Przybylski
authors.forename: Manuela
authors.initials: M
authors.lastname: Murariu
authors.forename: Ferenc
authors.initials: F
authors.lastname: Hudecz
authors.forename: Gabi
authors.initials: G
authors.lastname: Drochioiu
mesh_terms: D003300:Copper / Q000737:chemistry*; D006863:Hydrogen-Ion Concentration; D007202:Indicators and Reagents; D008956:Models, Chemical; D009842:Oligopeptides / Q000138:chemical synthesis / Q000737:chemistry; D010455:Peptides / Q000138:chemical synthesis* / Q000737:chemistry*; D021241:Spectrometry, Mass, Electrospray Ionization
chemical_list: D007202:Indicators and Reagents; D009842:Oligopeptides; D010455:Peptides; D003300:Copper; C046274:glycyl-glycyl-glycyl-glycine