Crunching biofilament rings

  title={Crunching biofilament rings},
  author={Julien Fierling and Martin Michael M{\"u}ller and Herv'e Mohrbach and Albert Johner and Igor M. Kuli'c},
  journal={Europhysics Letters},
We discuss a curious example for the collective mechanical behavior of coupled non-linear monomer units entrapped in a circular filament. Within a simple model we elucidate how multistability of monomer units and exponentially large degeneracy of the filament's ground state emerge as a collective feature of the closed filament. Surprisingly, increasing the monomer frustration, i.e., the bending prestrain within the circular filament, leads to a conformational softening of the system. The… 

How bio-filaments twist membranes.

In the limit of small deformations, a general expression for the energy and the deformation field of the membrane is derived that is specialised to different important cases including closed and helical bio-filaments.

Semiflexible Chains at Surfaces: Worm-Like Chains and beyond

An extended review of recent numerical and analytical studies on semiflexible chains near surfaces undertaken at Institut Charles Sadron with a focus on static properties, and a number of augmented models, like the (super) helical WLC model, the polymorphic model of microtubules and a model with (strongly) nonlinear flexural elasticity are presented.



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It is shown that when exposed to fluorescence excitation light, rhodamine-phalloidin-labeled filaments undergo a change in their natural twist that induces a localized small-wavelength supercoiling transition of absorbed actin rings.

Continuum model for polymorphism of bacterial flagella.

A new theory for polymorphism is proposed, whose essential elements are two molecular switches and an elastic mismatch strain between the inner and outer cores of the filament.

Mechanochemical action of the dynamin protein.

A generalized hydrodynamics description of the conformational change of large dynamin-membrane tubes, taking into account GTP consumption as a free-energy source is developed.

Biofilaments as annealed semi-flexible copolymers

In many in vivo or in vitro situations, biofilaments manifest some annealed heterogeneity and should be considered as annealed random copolymers. The building blocks of the filaments differ from each

Tubulin bistability and polymorphic dynamics of microtubules.

It is shown that GDP-tubulin bistability consistently explains unusual dynamic fluctuations, the apparent length-stiffness relation of grafted taxol-stabilizedmicrotubules, and the curved-helical appearance of microtubules in general.

Helices at interfaces

It is shown that confined filaments can thermally switch between discrete topological twist quantized states, with some of the states exhibiting dramatically enhanced cyclisation probability while others displaying surprising hyperflexibility.

Reverse engineering the euglenoid movement

It is found that metaboly accomplishes locomotion at hydrodynamic efficiencies comparable to those of ciliates and flagellates, and that the pellicle may serve as a model for engineered active surfaces with applications in microfluidics.

Soft Matter

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  • Rev. Lett. 105, 268102 (2010); Eur. Biophys. J. 41, 217
  • 2012