The Tat system consists of three membrane proteins (TatA, TatB and TatC) which in a still unknown manner accomplish the transmembrane passage of completely folded proteins and protein complexes.

(C) 2013 Institut Pasteur. Published by Elsevier Masson SAS. All rights reserved.”
“The type II secretion system is utilized by many Gram-negative bacteria to export folded proteins to the surface and/or the extracellular environment of the cell. Although the function of the system is to move proteins from the periplasm to the outside of the cell, it is a Lapatinib solubility dmso large trans-envelope structure composed of more than a dozen different proteins present in multiple copies, including peripheral, integral inner membrane and integral outer membrane proteins plus a pseudopilus stretching

between them. The establishment of this structure as an integral component of the entire envelope including the peptidoglycan layer between the two membranes requires assembly. Many of the participants and processes involved in this assembly have now been established, while other aspects remain to be discovered or more fully understood. (C) 2013 Institut Pasteur. Published by Elsevier Masson SAS. All rights reserved.”
“Type II secretion systems (T2SSs) share common origins and structure with archaeal flagella (archaella) and pili, bacterial competence systems and type IV pili. All of these systems use a conserved ATP-powered Danusertib machinery to assemble helical fibers that are anchored in the plasma membrane. The T2SSs assemble pseudopili, periplasmic filaments that promote extracellular secretion of folded periplasmic proteins. Comparative analysis of T2SSs and related fiber assembly nanomachines might provide important clues on their functional specificities and dynamics. This review focuses the on recent developments in the study of pseudopilus structure and biogenesis, and discusses mechanistic models of pseudopilus function in protein secretion. (C) 2013 Institut Pasteur. Published by Elsevier Masson SAS. All rights reserved.”
“Type

II secretion systems (T2SSs) generally release their substrates into the culture medium. A few T2SS substrates remain anchored to or bound at the surface of the bacteria after secretion. Since they handle already folded proteins, T2SSs are the best way for bacteria to target, at their surface, proteins containing a cofactor, proteins that have to be folded in the cytoplasm or in the periplasm, or multimeric proteins. However, how a T2SS deals with membrane-anchored proteins is not yet understood. While this type of protein has until now been overlooked, new proteomic approaches will facilitate its identification. (C) 2013 Institut Pasteur. Published by Elsevier Masson SAS. All rights reserved.”
“Autotransporters are widely distributed among Gram-negative bacteria. They can have a large variety of functions and many of them have a role in virulence.