Related Experiment Video
Updated: May 22, 2026

Biotinylated Cell-penetrating Peptides to Study Intracellular Protein-protein Interactions
Published on: December 20, 2017
The mechanism of Tat-dependent protein translocation
Thomas Brüser1, Carsten Sanders2,3,4
1Institute of Microbiology, Leibniz University Hannover, 30419 Hannover, Germany.
Abstract:
The twin-arginine translocation (Tat) system is the only general pathway for the transport of folded proteins across energized biological membranes. It is found in the bacterial or archaeal cytoplasmic membrane, the plant thylakoid membrane or the inner membrane of plant mitochondria. The biological importance of this translocation system can be exemplified by the fact that all bacterial or plant photosynthesis and photosynthetic oxygen evolution on earth requires this system. Despite many biochemical and biophysical studies, the Tat mechanism has been puzzling since the system was discovered in the 1990ies. Important characteristics of the Tat system could not be explained, and also recent high-resolution structures of the Tat system's core with bound substrate has not led to a general transport mechanism yet. In this integrative review, we attempted to answer the key open questions relevant to the Tat mechanism and thereby developed an in its molecular detail new comprehensive explanation of how folded proteins are translocated across membranes by the Tat system.
Related Concept Videos
Bacterial Translocation and Protein Secretion
Cotranslational Protein Translocation
Sec61 channel partners for cotranslational translocation
During cotranslational translocation, the Sec61 channel partners with the signal recognition particle (SRP), the signal recognition particle receptor (SR), and the ribosomes to transport the nascent polypeptide chain...
Translocation of Proteins into the Mitochondria
Sorting of outer membrane proteins:
Mitochondrial outer membrane proteins are of two types: the transmembrane, beta-barrel porins, and the membrane-anchored, alpha-helical proteins. Beta-barrel porin precursors are translocated by the TOM complex and inserted into the outer mitochondrial membrane by the SAM complex. In contrast,...
Energy to Drive Translocation
Generally, polypeptides are unfolded by two distinct...
Protein Transport to the Thylakoids
Tail-anchoring of Proteins in the ER Membrane

