Crystalline Bacterial Cell Surface Layers

Crystalline surface layers (S-layers) represent an almost universal feature of archaebacterial cell envelopes and can be found in gram-positive and gram-negative eubacterial species from nearly all phylogenetic branches. S-layers consist of a single protein- or glycoprotein species and thus can be considered as one of the most primitive membrane structures developed during evolution. Prokaryotes carrying S-layers are ubiquitously found in every part of the biosphere. This supports the conce...