A hyperthermostable protease of the subtilisin family bound to the surface layer of the Archaeon Staphylothermus marinus

BackgroundStaphylothermus marinus, an archaeon isolated from a geothermally heated marine environment, is a peptide-fermenting, sulphur-dependent organism with an optimum growth temperature of 92 °C. It forms grapes of cells, which adhere to each other and to sulphur granules via their surface layer. This glycoprotein layer forms a canopy which is held at a distance of about 70 nm from the cell membrane by membrane-anchored stalks, thereby...