I. Basic and applied S-layer research: an overview

S-layers are crystalline monomolecular assemblies of protein or glycoprotein, which represent one of the most common cell surface structures in Archaea and Bacteria. As porous lattices completely covering the cell surface they can provide prokaryotic cells with selection advantages by functioning as protective coats, as structures involved in cell adhesion and surface recognition, as molecule or ion traps, and molecular sieves. In Archaea, which possess S-layers as exclusive cell wall component, the (glyco)protein lattices function as cell shape determining/maintaining framework. Studies on structure, chemistry, genetics, assembly and function of S-layers revealed a considerable application potential for the regular arrays in biotechnology, biomimetics, biomedicine and molecular nanotechnology.