Mechanism of anchoring proteins on the cell envelope

Surface proteins, essential structural components of bacterial cell wall, are synthesized as precursors equipped with specific functional domains. The N-terminal signal module enables translocation across the plasma membrane via Sec or Tat pathways, while sorting motif, located in the C-terminus, is responsible for protein attachment to the cell wall peptidoglycan. Only exception are lipoproteins which lipoylated cysteinyl residue connected with bacterial membrane is in N-terminal part of protein. Most of surface proteins, as surface (S-) layer proteins, internalins or autolysins, are linked to the different structures of cell wall through non covalent forces. From the other hand, molecules with LPXTG motif, which attachment involves sortase activity, are linked to the peptidoglycan by covalent bond. Due to structural, chemical and physicochemical properties, surface proteins are attractive components of diverse industrial or medical systems. Knowledge about mechanism of anchoring proteins to the cell envelope will open new possibility of their applications.