Lipids Activate SecA for High Affinity Binding to the SecYEG Complex.
Protein translocation across the bacterial cytoplasmic membrane is an essential process catalyzed predominantly by the Sec translocase. This system consists of the membrane-embedded protein-conducting channel SecYEG, the motor ATPase SecA, and the heterotrimeric SecDFyajC membrane protein complex. Previous studies suggest that anionic lipids are essential for SecA activity and that the N terminus of SecA is capable of penetrating the lipid bilayer. The role of lipid binding, however, has remained elusive. By employing differently sized nanodiscs reconstituted with single SecYEG complexes and comprising varying amounts of lipids, we establish that SecA gains access to the SecYEG complex via a lipid-bound intermediate state, whereas acidic phospholipids allosterically activate SecA for ATP-dependent protein translocation.
From the Molecular Microbiology, Groningen Biomolecular Sciences and Biotechnology Institute and Zernike Institute for Advanced Materials and.
Sabrina
S
Koch
From the Molecular Microbiology, Groningen Biomolecular Sciences and Biotechnology Institute and Zernike Institute for Advanced Materials and.
Janny G
JG
de Wit
From the Molecular Microbiology, Groningen Biomolecular Sciences and Biotechnology Institute and Zernike Institute for Advanced Materials and.
Iuliia
I
Vos
the Single-molecule Biophysics, Zernike Institute for Advanced Materials, University of Groningen, 9747 AG Groningen, The Netherlands.
Jan Peter
JP
Birkner
the Polymer Chemistry and Bioengineering, Zernike Institute for Advanced Materials, 9747 AG, Groningen, The Netherlands, and.
Pavlo
P
Gordiichuk
the Polymer Chemistry and Bioengineering, Zernike Institute for Advanced Materials, 9747 AG, Groningen, The Netherlands, and.
Andreas
A
Herrmann
the Single-molecule Biophysics, Zernike Institute for Advanced Materials, University of Groningen, 9747 AG Groningen, The Netherlands.|the School of Chemistry, University of Wollongong, Wollongong, New South Wales 2522, Australia.
Antoine M
AM
van Oijen
From the Molecular Microbiology, Groningen Biomolecular Sciences and Biotechnology Institute and Zernike Institute for Advanced Materials and a.j.m.driessen@rug.nl.
Arnold J M
http://orcid.org/0000-0001-9258-9104
AJ
Driessen
D000251:Adenosine Triphosphatases / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D001426:Bacterial Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D004926:Escherichia coli / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D029968:Escherichia coli Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D008051:Lipid Bilayers / Q000737:chemistry; D010743:Phospholipids / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D021381:Protein Transport / Q000502:physiology; D000069816:SEC Translocation Channels / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D000081416:SecA Proteins
D001426:Bacterial Proteins; D029968:Escherichia coli Proteins; D008051:Lipid Bilayers; D010743:Phospholipids; D000069816:SEC Translocation Channels; C065493:SecE protein, E coli; C088616:SecG protein, E coli; C057841:SecY protein, E coli; D000251:Adenosine Triphosphatases; D000081416:SecA Proteins
SecA; SecYEG; apolipoprotein; lipid bilayer; membrane biophysics; membrane function; membrane protein; nanodiscs; protein-lipid interaction; scaffold protein