Caddisfly silk

The silk’s structure is mostly conserved among many different caddisfly species, and can be used to bind debris including rocks, sticks, twigs and shells, as well as to build nets for catching prey.

Caddisflies, which spend the majority of their life cycle in the larval stage, need these casings to protect their underbellies and pupate.

Because their silk must be able to bind to a variety of components while completely submerged in water, it is therefore being studied for potential applications as a waterproof adhesive.

The β-sheet motif of caddisfly H-fibroin was found to have a (SX)4 repeating pattern, meaning serine alternating with usually isoleucine or valine.

[6] This negatively charged group suggests that ionic interactions, rather than hydrogen bonding, may explain the unusual strength of caddisfly silk.