title: Coupe du roi bisection of proteins. Spontaneous tetramerization of two peptides that span the sequence of the rabbit uteroglobin monomer.
abstract: The study of dividing objects into isometric segments has yielded novel approaches to the synthesis of high-symmetry organic compounds. Reported herein is the first application of this concept to a protein, rabbit uteroglobin (UG). Bisection of UG into two identical homochiral segments led to the design of the heterodimeric 70mer peptide alpha(1,2)-S-S-alpha(3,4) that spans the sequence of the native UG monomer. The ability of this compound to form a globular 140mer tetramer consisting of two noncovalently bound heterodimers was assessed by ultracentrifugation at sedimentation equilibrium and by fluorescent spectroscopy. On the other hand, the monomeric peptides alpha(1,2)-SH and alpha(3,4)-SH were shown to selectively form the alpha(1,2)-S-S-alpha(3,4) heterodimer via spontaneous air oxidation in phosphate buffer at neutral pH.
authors.affiliation: Department of Organic Chemistry, Martí i Franquès 1, Universitat de Barcelona, Barcelona 08028, Spain. enicolas@ub.edu
authors.forename: Ernesto
authors.initials: E
authors.lastname: Nicolás
authors.forename: Cristina
authors.initials: C
authors.lastname: Ferrer
authors.forename: Lorena
authors.initials: L
authors.lastname: Taboada
authors.forename: Ernest
authors.initials: E
authors.lastname: Giralt
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D002942:Circular Dichroism; D008958:Models, Molecular; D008969:Molecular Sequence Data; D010084:Oxidation-Reduction; D010446:Peptide Fragments / Q000138:chemical synthesis / Q000737:chemistry; D017434:Protein Structure, Tertiary; D011817:Rabbits; D013050:Spectrometry, Fluorescence; D014461:Ultracentrifugation; D014598:Uteroglobin / Q000138:chemical synthesis / Q000737:chemistry*
chemical_list: D010446:Peptide Fragments; D014598:Uteroglobin