Shear-Induced Self-Assembly of Native Silk Proteins into Fibrils Studied by Atomic Force Microscopy

作者：Imke Greving, Minzhen Cai, Fritz W. Vollrath, Hannes C. Schniepp · 发表于：Biomacromolecules · 年份：2012 · DOI：10.1021/bm201509b · 被引用次数：141 · 研究领域：Silk-based biomaterials and applications、Biochemical and Structural Characterization、Adhesion, Friction, and Surface Interactions

Noncontact mode atomic force microscopy was used to investigate native silk proteins prepared in different ways. Low protein concentrations revealed that single protein molecules exhibit a simple, round shape with apparent diameters of 20-25 nm. Shearing the native protein solutions after extraction from the gland and prior to drying led to a beads-on-a-string assembly at the nanometer scale. Protein concentration had a significant effect on the morphology of the protein assemblies. At higher protein concentrations, shear-induced alignment into nanofibrils was observed, while lower concentrations lead to the formation of much thinner fibrils with a width of about 8 nm.