Coupling of protein sheet crystals (S-layers) to phospholipid monolayers

The coupling of bacterial S-layer proteins to phospholipid membranes has be en studied in molecular detail with respect to, particularly, the lipid hea dgroups. Emphasis has been laid on two of the best characterized protein sp ecies, the S-layer protein from Bacillus sphaericus CCM2177 and from Bacill us coagulans E38-66/V1. A combination of fluorescence microscopy, surface s ensitive scattering techniques (grazing-incidence X-ray diffraction as well as X-ray and neutron reflectometry) and infrared spectroscopy (FT-IRRAS), applied to surface monolayers of lipids onto which the protein has been rec onstituted as continuous molecular crystal sheets, provides a wealth of inf ormation which has been utilized to propose detailed molecular models.