Optimal protein sequence design mitigates mechanical failure in silk beta-sheet nanocrystals

Abstract

Spider silk fiber possesses exceptional mechanical properties such as high tensile strength, toughness, and elasticity in tensile loading. Previous experimental and computational studies have shown that extraordinary mechanical strength of silk fiber is mostly attributed to the hierarchical arrangement of antiparallel β-sheet nanocrystals and role of β-strand length, arrangements, and H-bond interactions. Despite these studies, the dependence of mechanical properties of silk nanocrystal on their sequence motifs remains largely unexplored.