<p>Spider and silkworm silks are renowned for their exceptional mechanical properties, which arises from their ultrastructural organization. However, this architecture remains incompletely understood. Here, we apply cryo-electron tomography to examine the hierarchical organization of silkworm, spider, and artificial silks. In silkworm silk, we observe nanofibrils of ~3.6 nm in diameter, interconnected by abundant bridges and representing the smallest fibrillar features currently accessible by cryo-ET. These nanofibrils align with the fiber axis and are organized into a herringbone pattern, with stacked layers building the micron-scale filament. Spider silk displays densely packed nanofibrils with near-perfect axial alignment and minimal voids. In contrast, silkworm silk shows regionally heterogeneous gaps, whereas artificial silk lacks the ordered packing characteristic of natural materials. These observations provide a structural basis for understanding silk formation and may guide future biomimetic fiber design.</p>

错误:搜索内容不能为空,请输入英文关键词
错误:关键词超出字数限制,请精简
高级检索

Cryo-ET comparison of the hierarchical ultrastructure of silkworm, spider, and artificial silk fibers

  • Kai Song,
  • Haonan Zhang,
  • Xueli Zhang,
  • Yan Li,
  • Ping Zhu

摘要

Spider and silkworm silks are renowned for their exceptional mechanical properties, which arises from their ultrastructural organization. However, this architecture remains incompletely understood. Here, we apply cryo-electron tomography to examine the hierarchical organization of silkworm, spider, and artificial silks. In silkworm silk, we observe nanofibrils of ~3.6 nm in diameter, interconnected by abundant bridges and representing the smallest fibrillar features currently accessible by cryo-ET. These nanofibrils align with the fiber axis and are organized into a herringbone pattern, with stacked layers building the micron-scale filament. Spider silk displays densely packed nanofibrils with near-perfect axial alignment and minimal voids. In contrast, silkworm silk shows regionally heterogeneous gaps, whereas artificial silk lacks the ordered packing characteristic of natural materials. These observations provide a structural basis for understanding silk formation and may guide future biomimetic fiber design.