Issue
EPL
Volume 86, Number 6, June 2009
Article Number 68002
Number of page(s) 6
Section Interdisciplinary Physics and Related Areas of Science and Technology
DOI http://dx.doi.org/10.1209/0295-5075/86/68002
Published online 09 July 2009
EPL, 86 (2009) 68002
DOI: 10.1209/0295-5075/86/68002

Zipping mechanism for force generation by growing filament bundles

T. Kühne1, R. Lipowsky1 and J. Kierfeld1, 2

1   Max Planck Institute of Colloids and Interfaces - Science Park Golm, 14424 Potsdam, Germany, EU
2   Physics Department, TU Dortmund University - 44221 Dortmund, Germany, EU

Jan.Kierfeld@tu-dortmund.de

received 19 January 2009; accepted in final form 2 June 2009; published June 2009
published online 9 July 2009

Abstract
We investigate the force generation by polymerizing bundles of filaments, which form because of short-range attractive filament interactions. We show that bundles can generate forces by a zipping mechanism, which is not limited by buckling and operates in the fully buckled state. The critical zipping force, i.e. the maximal force that a bundle can generate, is given by the adhesive energy gained during bundle formation. For opposing forces larger than the critical zipping force, bundles undergo a force-induced unbinding transition. For larger bundles, the critical zipping force depends on the initial configuration of the bundles. Our results are corroborated by Monte Carlo simulations.

PACS
87.16.Ka - Filaments, microtubules, their networks, and supramolecular assemblies.
87.16.A- - Theory, modeling, and simulations.
87.15.rp - Polymerization.

© EPLA 2009