Functionalisation of surfaces with S-layers

Two-dimensional bacterial surface layer protein crystals (S-layers) are the most commonly observed cell surface structures in prokaryotic organisms (bacteria and archaea). Isolated S-layer proteins have the intrinsic tendency to self-assemble into two-dimensional arrays in suspension and at various interfaces. Basic research on the structure, genetics, chemistry, morphogenesis and function of S-layers has led to a broad spectrum of applications in molecular nanotechnology and biomimetics. The possibility to change the natural properties of S-layer proteins by genetic manipulation opens new ways for the tuning of their structural and functional features. Functionalised S-layer proteins that maintain their propensity for selfassembly have led to new affinity matrices, diagnostic tools, vaccines or biocompatible surfaces, as well as to biological templating or specific biomineralisation strategies at surfaces.