Evidence for the Glycoprotein Nature of Eubacterial S-Layers

So far, about 200 different species of archaebacteria and eubacteria from most phylogenetic branches have been identified to carry regularly arranged surface layers (S-layers) (Sleytr and Messner, 1983, Sleytr et al. 1986a). Thus, S-layers appear to be a universal rather than a unique feature of prokaryotic cells. Quantitative calculations have revealed that S-layers can account for up to 10% of the total cell protein and therefore represent the major cell protein.