Sec-independent protein translocase protein TatA/B/E (IPR003369)

Short name: TatA/B/E

Overlapping homologous superfamilies


Family relationships


Translocation of proteins across the two membranes of Gram-negative bacteria can 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 [PMID: 9649434].

In some bacterial species, however, there exists a system that operates independently of the Sec pathway [PMID: 10652088]. 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 [PMID: 10652088]. The gene products responsible for the Sec-independent pathway are called TatA, TatB, TatC and TatE.

This entry represents the related TatA, TatB and TatE proteins.

GO terms

Biological Process

GO:0015031 protein transport

Molecular Function

No terms assigned in this category.

Cellular Component

No terms assigned in this category.

Contributing signatures

Signatures from InterPro member databases are used to construct an entry.