Sébastien Neukirch Institut Jean le Rond d'Alembert Centre National de la Recherche Scientifique Université Pierre et Marie Curie Paris, France tel: +33 1 44 27 72 61 fax : +33 1 44 27 52 59 e-mail: sebastien.neukirch (-atat-) upmc.fr

Chirality of coiled-coils: elasticity matters

Sébastien Neukirch, Alain Goriely, and Andrew Hausrath

Physical Review Letters, 100 (2008) 038105

also selected in the Virtual Journal of Biological Physics Research -- February 1, 2008 Volume 15, Issue 3.

Abstract : Coiled-coils are important protein-protein interaction motifs with high specificity that are used to assemble macromolecular complexes. Their simple geometric organization, consisting of $\alpha$-helices wrapped around each other, confers remarkable mechanical properties. A geometrical and mechanical continuous model taking into account sequence effects and based on the super-helical winding of the constituent helices is introduced and a continuous family of solutions in which the oligomerization interactions are satisfied is derived. From these solutions, geometric and structural properties, such as the chirality and pitch of the coiled-coil and the location of residues, are obtained. The theoretical predictions are compared to X-ray data from the leucine zipper motif.

Key words : chirality, helix, super-helix, force-extension, keratin, collagen