| Primary Identifier | IPR018448 | Type | Family |
| Short Name | TatB |
| description | Translocation of proteins across the two membranes of Gram-negative bacteriacan be carried out via a number of routes. Most proteins marked for export carry a secretion signal at their N terminus, and are secreted by the general secretory pathway. The signal peptide is cleaved as they pass through the outer membrane. Other secretion systems include the type III system found in a select group of Gram-negative plant and animal pathogens, and the CagA system of Helicobacter pylori [].In some bacterial species, however, there exists a system that operates independently of the Sec pathway []. It selectively translocates periplasmic-bound molecules that are synthesised with, or are in close association with, "partner"proteins bearing an (S/T)RRXFLK twin arginine motif at the N terminus. The pathway is therefore termed the Twin-Arginine Translocation or TAT system. Surprisingly, the four components that make up the TAT system are structurally and mechanistically related to a pH-dependent import system in plant chloroplast thylakoid membranes []. Thegene products responsible for the Sec-independent pathway are called TatA,TatB, TatC and TatE.This entry represents Sec-independent protein translocase protein TatB (TatB) and similar proteins predominantly found in Proteobacteria. TatB is essential for the secretion of large folded proteins containing a characteristic twin-arginine motif in their signal peptide across membranes. It may form an oligomeric binding site that transiently accommodates folded Tat precursor proteins before their translocation []. It may form a circular arrangement with TatC []. |
