Protein fibres are found virtually everywhere in nature, including in spider silk, wood, the spaces between tissue cells, in tendons, or as a natural sealant for small wounds. These protein nanofibres have outstanding properties such as high stability, biodegradability, and antibacterial effects. Artificially creating these fibres is not easy, much less assigning them specific functions. These issues are discussed by materials scientists from Friedrich Schiller University Jena (Germany) in the latest issue of ACS Nano.