Magnetic Au Nanoparticles on Archaeal S-Layer Ghosts as Templates

Cell-ghosts representing empty cells of the archaeon Sulfolobus acidocaldarius, consisting only of their highly ordered and unusually stable outermost proteinaceous surface layer (S-layer), were used as templates for Au nanoparticles fabrication. The properties of these archaeal Au nanoparticles differ significantly from those produced earlier by us onto bacterial S-layer sheets. The archaeal Au nanoparticles, with a size of about 2.5 nm, consist exclusively of metallic Au(0), while those produced on the bacterial S-layer had a size of about 4 nm and represented a mixture of Au(0) and Au(III) in the ratio of 40 to 60 %.