Fold and function of polypeptide transport-associated domains responsible for delivering unfolded proteins to membranes

DOI: 10.1111/j.1365-2958.2008.06225.x
PMID: 18430136

Authors: Timothy Knowles (University of Birmingham) , Mark Jeeves (University of Birmingham) , Saeeda Bobat (University of Birmingham) , Felician Dance (University of Birmingham) , Darren Mcclelland (University of Birmingham) , Tracey Palmer (University of Dundee) , Michael Overduin (University of Birmingham) , Ian R. Henderson (University of Birmingham)
Co-authored by industrial partner: No

Type: Journal Paper
Journal: Molecular Microbiology , VOL 68 (5) , PAGES 1216-1227

State: Published (Approved)
Published: June 2008

Abstract: Membranes of Gram-negative bacteria, mitochondria and chloroplasts receive and fold beta-barrel transmembrane proteins through the action of polypeptide transport-associated (POTRA) domains. In Escherichia coli, folding substrates are inserted into the outer membrane by the essential protein YaeT, a prototypic Omp85 protein. Here, the articulation between tandem POTRA domains in solution is defined by nuclear magnetic resonance (NMR) spectroscopy, indicating an unprecedented juxtaposition. The novel solution orientations of all five POTRA domains are revealed by small-angle X-ray scattering of the entire 46 kDa periplasmic region. NMR titration studies show that strands from YaeT's canonical folding substrate, PhoE, bind non-specifically along alternating sides of its mixed beta sheets, thus providing an ideal platform for helping to fold nascent outer-membrane proteins. Together, this provides the first structural model of how multiple POTRA domains recruit substrates from the periplasmic solution into the outer membrane.

Diamond Keywords: Bacteria

Subject Areas: Biology and Bio-materials


Instruments: I22-Small angle scattering & Diffraction

Added On: 24/04/2009 10:36

Discipline Tags:

Biophysics Life Sciences & Biotech

Technical Tags:

Scattering Small Angle X-ray Scattering (SAXS)