An alternative model of the twin arginine translocation system

authored by

Thomas Brüser, Carsten Sanders

Abstract

The twin arginine translocation (Tat) system is a machinery which can translocate folded proteins across energy transducing membranes. Currently it is supposed that Tat substrates bind directly to Tat translocon components before a ΔpH-driven translocation occurs. In this review, an alternative model is presented which proposes that membrane integration could precede Tat-dependent translocation. This idea is mainly supported by the recent observations of Tat-independent membrane insertion of Tat substrates in vivo and in vitro. Membrane insertion may allow i) a quality control of the folded state by membrane bound proteases like FtsH, ii) the recognition of the membrane spanning signal peptide by Tat system components, and iii) a pulling mechanism of translocation. In some cases of folded Tat substrates, the membrane targeting process may require ATP-dependent N-terminal unfolding-steps.

Organisation(s)

Institute of Microbiology

External Organisation(s)

Martin Luther University Halle-Wittenberg
University of Pennsylvania

Type

Review article

Journal

Microbiological Research

Volume

158

Pages

7-17

No. of pages

11

ISSN

0944-5013

Publication date

2003

Publication status

Published

Peer reviewed

Yes

ASJC Scopus subject areas

Microbiology

Electronic version(s)

https://doi.org/10.1078/0944-5013-00176 (Access: Open)