Article
Marco Barba and Anatoli P. Sobolev contributed equally to this work.
Received: 30 September 2008; Revised: 9 December 2008; Accepted: 17 December 2008
10.1002/pro.58 About DOI
Cupryphans, metal-binding, redox-active, redesigned conopeptides |
| Marco Barba 1 2, Anatoli P. Sobolev 3, Cristina Romeo 4, M. Eugenia Schininà 4, Donatella Pietraforte 5, Luisa Mannina 3 6, Giovanni Musci 1 6, Fabio Polticelli 1 * |
| 1Department of Biology, University Roma Tre, Viale G. Marconi 446, 00146 Rome, Italy 2Department of Protein Chemistry,  Cesare Serono Research Institute, Via di valle Caia 22, 00040 Ardea, Italy3Institute of Chemical Methodologies, CNR, Via Salaria km 29.300, 00016 Monterotondo Stazione, Roma, Italy 4Department of Biochemical Sciences, University of Rome La Sapienza, P.le A. Moro 5, 00185 Rome, Italy5Department of Cell Biology and Neurosciences, Istituto Superiore di Sanità, viale Regina Elena 299, 00161 Rome, Italy 6STAAM Department, University of Molise, Via De Sanctis, 86100 Campobasso, Italy |
| email: Fabio Polticelli (polticel@uniroma3.it) |
*Correspondence to Fabio Polticelli, Department of Biology, University Roma Tre, Viale Marconi 446, 00146 Rome, Italy
Marco Barba and Anatoli P. Sobolev contributed equally to this work.Funded by:
MIUR FIRB; Grant Number: RBAU01YMY5
| Keywords |
| protein design conopeptides Contryphan metalloproteins superoxide dismutase |
| Abstract |
| Contryphans are bioactive peptides, isolated from the venom of marine snails of the genus Conus, which are characterized by the short length of the polypeptide chain and the high degree of unusual post-translational modifications. The cyclization of the polypeptide chain through a single disulphide bond, the presence of two conserved Pro residues, and the epimerization of a Trp/Leu residue confer to Contryphans a stable and well-defined structure in solution, conserved in all members of the family, and tolerant to multiple substitutions. The potential of Contryphans as scaffolds for the design of redox-active (macro)molecules was tested by engineering a copper-binding site on two different variants of the natural peptide Contryphan-Vn. The binding site was designed by computational modeling, and the redesigned peptides were synthesized and characterized by optical, fluorescence, electron spin resonance, and nuclear magnetic resonance spectroscopy. The novel peptides, named Cupryphan and Arg-Cupryphan, bind Cu2+ ions with a 1:1 stoichiometry and a Kd in the 100 nM range. Other divalent metals (e.g., Zn2+ and Mg2+) are bound with much lower affinity. In addition, Cupryphans catalyze the dismutation of superoxide anions with an activity comparable to other nonpeptidic superoxide dismutase mimics. We conclude that the Contryphan motif represents a natural robust scaffold which can be engineered to perform different functions, providing additional means for the design of catalytically active mini metalloproteins. |
Received: 30 September 2008; Revised: 9 December 2008; Accepted: 17 December 2008
| Digital Object Identifier (DOI) |
10.1002/pro.58 About DOI
