Volume exclusion and elasticity driven directional transport: an alternative model for bacterium motility

TL;DR

This paper introduces a new model explaining bacterium motility by emphasizing volume exclusion and elasticity, which accounts for super-diffusive transport and directional movement driven by strong attractive interactions.

Contribution

The model provides a novel explanation for bacterial motility that overcomes limitations of the Brownian ratchet model by incorporating volume exclusion and elasticity effects.

Findings

Super-diffusive transport observed in the model.

Model explains directional movement in actin-polymerization systems.

Contrasts with Brownian ratchet model limitations.

Abstract

On the basis of a model we capture the role of strong attractive interaction in suppressing the rotational degrees of freedom of the system and volume exclusion in keeping microscopic symmetry-breaking intact to result in super-diffusive transport of small systems in a thermal atmosphere over a large time scale. Our results, characterize such systems on the basis of having a super-diffusive intermediate regime in between a very small and large time scales of diffusive regimes. Although, the Brownian ratchet model fails to account for the origin of motility in actin polymerization propelled directional motion of bacterium like Listeria Monocytogene (LM) and similar bio-mimetic systems due to the presence of strong attractive forces, our model can account for the origin of directional transport in such systems on the basis of the same interactions.