Fig. 2.

Tridimensional structures of Bombyx mori’s silk fiber (left) and Aranea diadematus’s (right). The silkworm’s fiber varies between 10 and 20 µm, the spider’s dragline between 3 and 5 µm. Unlike in silkworm’s silk, there is no sericin in spiders’ dragline, but the glycoproteins layer protects from bacterial and fungal infections (Doblhofer et al. 2015). Nanofibrils of fibroin (in spiders and silkworms indifferently), which are between 20 and 60 nm large, are not represented at scale