Active Polymers Confer Fast Reorganization Kinetics

TL;DR

This paper demonstrates that active biopolymers can reorganize faster than passive polymers of the same length due to their energy-consuming activity, which alters their scaling behavior and enhances dynamic responsiveness.

Contribution

The study introduces a simple active-polymer model showing improved reorganization kinetics, with MFPT scaling as the square root of mean length, unlike passive polymers.

Findings

Active polymers have faster reorganization than passive ones at equal length.

Equilibrium polymers exhibit linear MFPT scaling with mean length.

Active polymers achieve sublinear MFPT scaling, enhancing biological responsiveness.

Abstract

Many cytoskeletal biopolymers are "active," consuming energy in large quantities. In this Letter, we identify a fundamental difference between active polymers and passive, equilibrium polymers: for equal mean lengths, active polymers can reorganize faster than equilibrium polymers. We show that equilibrium polymers are intrinsically limited to linear scaling between mean lifetime and mean length, MFPT ~ <L>, by analogy to 1-d Potts models. By contrast, we present a simple active-polymer model that improves upon this scaling, such that MFPT ~ <L>^{1/2}. Since to be biologically useful, structural biopolymers must typically be many monomers long, yet respond dynamically to the needs of the cell, the difference in reorganization kinetics may help to justify active polymers' greater energy cost. PACS numbers: 87.10.Ed, 87.16.ad, 87.16.Ln