Steered Molecular Dynamic Simulations of the Neisseria Meningitidis Type IV Pilus Reveal Structural Changes under Force

Abstract

Our group is using computer simulations to investigate the strength of bacterial filaments called type IV pili. Type IV pili extend from bacterial cells and are used in a wide variety of functions, including adhesion, motility, and infection. They are made of many copies of a protein called pilin, and can withstand very large tension forces. When type IV pili are stretched, they are known to elongate by approximately three times their initial length, and become significantly smaller in diameter. However, the details of this structural transition are unknown at the molecular scale. Our goal is to provide insight into how the structure of type IV pili change under force, which will provide a basic understanding of the strength and flexibility of these biopolymers.