Unlocking the Bacterial SecY Translocon

Overview

Journal Structure

Publisher Cell Press

Specialties Biochemistry
Biotechnology
Cell Biology
Molecular Biology

Date 2016 Mar 15

PMID 26973090

Citations 23

Authors

Robin A Corey

William J Allen

Joanna Komar

Simonas Masiulis

Sam Menzies

Alice Robson

Ian Collinson

Affiliations

Soon will be listed here.

Abstract

The Sec translocon performs protein secretion and membrane protein insertion at the plasma membrane of bacteria and archaea (SecYEG/β), and the endoplasmic reticular membrane of eukaryotes (Sec61). Despite numerous structures of the complex, the mechanism underlying translocation of pre-proteins, driven by the ATPase SecA in bacteria, remains unresolved. Here we present a series of biochemical and computational analyses exploring the consequences of signal sequence binding to SecYEG. The data demonstrate that a signal sequence-induced movement of transmembrane helix 7 unlocks the translocon and that this conformational change is communicated to the cytoplasmic faces of SecY and SecE, involved in SecA binding. Our findings progress the current understanding of the dynamic action of the translocon during the translocation initiation process. The results suggest that the converging effects of the signal sequence and SecA at the cytoplasmic face of SecYEG are decisive for the intercalation and translocation of pre-protein through the SecY channel.

Citing Articles

Dynamic coupling of fast channel gating with slow ATP-turnover underpins protein transport through the Sec translocon.

Crossley J, Allen W, Watkins D, Sabir T, Radford S, Tuma R EMBO J. 2024; 43(1):1-13.

PMID: 38177311 PMC: 10883268. DOI: 10.1038/s44318-023-00004-1.

A unifying mechanism for protein transport through the core bacterial Sec machinery.

Allen W, Collinson I Open Biol. 2023; 13(8):230166.

PMID: 37643640 PMC: 10465204. DOI: 10.1098/rsob.230166.

mRNA targeting eliminates the need for the signal recognition particle during membrane protein insertion in bacteria.

Sarmah P, Shang W, Origi A, Licheva M, Kraft C, Ulbrich M Cell Rep. 2023; 42(3):112140.

PMID: 36842086 PMC: 10066597. DOI: 10.1016/j.celrep.2023.112140.

Non-Specific Signal Peptidase Processing of Extracellular Proteins in N315.

Misal S, Ovhal S, Li S, Karty J, Tang H, Radivojac P Proteomes. 2023; 11(1).

PMID: 36810564 PMC: 9944065. DOI: 10.3390/proteomes11010008.

Interaction of the periplasmic chaperone SurA with the inner membrane protein secretion (SEC) machinery.

Troman L, Alvira S, Daum B, Gold V, Collinson I Biochem J. 2023; 480(4):283-296.

PMID: 36701201 PMC: 9987972. DOI: 10.1042/BCJ20220480.

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