Repeat-proteins films exhibit hierarchical anisotropic mechanical properties.

Complex hierarchical structures provide beneficial structure-property relationships that can be exploited for a variety of applications in engineering and biomedical fields. Here we report on molecular organization and resulting mechanical properties of self-assembled designed repeat-protein films. Wide-angle X-ray diffraction indicates the designed 18-repeat concensus tetratricopeptide repeat protein (CTPR18) orients normal to the casting surface, while small-angle measurements and electron microscopy show a through-plane transversely aligned laminar sheet-like morphology.