Quantized biopolymer translocation through nanopores: departure from simple scaling

TL;DR

This paper investigates how long biopolymers translocate through wide nanopores, revealing folding quantization that affects translocation times and enables faster translocation for sufficiently long polymers.

Contribution

It introduces the concept of folding quantization in biopolymer translocation through wide nanopores, showing its impact on translocation dynamics and cooperative behavior.

Findings

Folding quantization occurs during translocation.

Translocation time depends on the average folding number.

Long polymers translocate faster due to folding mechanisms.

Abstract

We discuss multiscale simulations of long biopolymer translocation through wide nanopores that can accommodate multiple polymer strands. The simulations provide clear evidence of folding quantization, namely, the translocation proceeds through multi-folded configurations characterized by a well-defined integer number of folds. As a consequence, the translocation time acquires a dependence on the average folding number, which results in a deviation from the single-exponent power-law characterizing single-file translocation through narrow pores. The mechanism of folding quantization allows polymers above a threshold length (approximately $1,000$ persistence lengths for double-stranded DNA) to exhibit cooperative behavior and as a result to translocate noticeably faster.