Bioengineering biomimetic membranescombining s-layer technology, polyelectrolyte multilayers and lipids

Resumen

A promising approach to generate biomimetic systems includes the combination of bacterial surface layer (S-layer) technology with polyelectrolyte multilayer (PEM) or lipids. In the last decade, protein adsorption on PEM and lipidic systems has shown to have many applications in biotechnology (biosensor building, biomimetic membranes, and artificial cells). As protein model, we use S-layers, which are one of the most common cell envelope components of prokaryotic organisms and archaea, composed of a single (glyco)protein, representing the simplest biological membrane developed during evolution. We have used the ability of S-layer subunits to self-assemble into 2-D crystalline arrays to generate biomimetic membranes. The affinity of S-layers to polyelectrolytes has been investigated through the building of sandwich-like supramolecular structure (PEM/S-layer/PEM/S-layer). The influence of the pH on the surface nanostructure, viscoelasticity and wetting properties of recrystallized S-layers has been also studied. The mechanical and thermal stability of the 2-D protein crystal on PEM have been determined. The amount of adsorbed S-protein and water content in the hybrid system has been estimated for the first time. The interaction of S-layer proteins with lipids varying charge and headgroup size has been also investigated.