Exploring the biomechanics of type IV pilus filaments under force using coarse grained molecular dynamics

Abstract

Type IV Pili (T4P) are long biopolymers made up of thousands of copies of a protein called pilin. T4P are found on a large variety of micro-organisms including Gram-positive and Gram-negative bacteria [1]. It has been experimentally demonstrated that T4P can withstand high tension forces (up to 10,000 times the bacterial bodyweight) and at the same time undergo a reversible conformational change that allows the filament to stretch to three times its original length and become 40% narrower [2]. However, the molecular scale mechanism of this extraordinary transition is still not clear.