title: Vicinal disulfide turns.
abstract: The formation of a disulfide bond between adjacent cysteine residues is accompanied by the formation of a tight turn of the protein backbone. In nearly 90% of the structures analyzed a type VIII turn was found. The peptide bond between the two cysteines is in a distorted trans conformation, the omega torsion angle ranges from 159 to -133 degrees, with an average value of 171 degrees. The constrained nature of the vicinal disulfide turn and the pronounced difference observed between the oxidized and reduced states, suggests that vicinal disulfides may be employed as a 'redox-activated' conformational switch.
authors.affiliation: International Centre for Genetic Engineering and Biotechnology, Padriciano 99, 34012 Trieste, Italy.
authors.forename: Oliviero
authors.initials: O
authors.lastname: Carugo
authors.forename: Masa
authors.initials: M
authors.lastname: Cemazar
authors.forename: Sotir
authors.initials: S
authors.lastname: Zahariev
authors.forename: Ilona
authors.initials: I
authors.lastname: Hudáky
authors.forename: Zoltán
authors.initials: Z
authors.lastname: Gáspári
authors.forename: András
authors.initials: A
authors.lastname: Perczel
authors.forename: Sándor
authors.initials: S
authors.lastname: Pongor
mesh_terms: D003545:Cysteine / Q000737:chemistry*; D004220:Disulfides / Q000737:chemistry*; D015202:Protein Engineering; D017510:Protein Folding; D017433:Protein Structure, Secondary
chemical_list: D004220:Disulfides; D003545:Cysteine