Phys.org July 21, 2021
A problem associated with recombinant spider silk fiber is the need to create β-nanocrystals, a main component of natural spider silk, which contributes to its strength. Researchers at Washington University redesigned the silk sequence by introducing amyloid sequences that have high tendency to form β-nanocrystals. They created different polymeric amyloid proteins using three well-studied amyloid sequences as representatives. The resulting proteins had less repetitive amino acid sequences than spider silk, making them easier to be produced by engineered bacteria. The longer the protein, the stronger and tougher the resulting fiber. The 128-repeat proteins resulted in a fiber with gigapascal strength which is stronger than common steel and the fibers’ toughness is higher than Kevlar, all previous recombinant silk fibers and natural spider silk fibers. The design strategy and the biosynthetic approach can be expanded to create numerous functional materials, and the macroscopic amyloid fibers will enable a wide range of mechanically demanding applications…read more. TECHNICAL ARTICLEÂ
