Dynamics of Enzyme Digestion of a Single Elastic Fiber Under Tension: An Anisotropic Diffusion Model

TL;DR

This study models the enzymatic degradation of a tensioned elastic fiber using an anisotropic diffusion model, revealing exponential stiffness decay with force-dependent dynamics and identifying key factors influencing degradation rates.

Contribution

Introduces an anisotropic diffusion model coupled with binding reactions to analyze enzyme-driven fiber degradation under tension, providing new insights into the process dynamics.

Findings

Fiber stiffness decreases exponentially over time.

Degradation rate increases with applied tension.

Model aligns with experimental observations.

Abstract

We study the enzymatic degradation of an elastic fiber under tension using an an isotropic random-walk model, coupled with binding-unbinding reactions that weaken the fiber. The fiber is represented by a chain of elastic springs in series, surrounded by two layers of sites along which enzyme molecules can diffuse. Through numerical simulations we show that the fiber stiffness decreases exponentially with two distinct regimes. The time constant associated with the first regime decreases with increasing applied force, which is in agreement with published experimental data. In addition, a simple mean field calculation allows us to partition the time constant into geometrical, chemical and externally controllable factors, which is corroborated by the simulations.