Detergents are often used to investigate the structure and dynamics of membrane proteins. Whereas the structural integrity seems to be preserved in detergents for many membrane proteins, their functional activity is frequently compromised, but can be restored in a lipid environment. Herein we show with per-residue resolution that while OmpX forms a stable ?-barrel in DPC detergent micelles, DHPC/DMPC bicelles, and DMPC nanodiscs, the pico- to nanosecond and micro- to millisecond motions differ substantially between the detergent and lipid environment. In particular for the ?-strands, there is pronounced dynamic variability in the lipid environment, which appears to be suppressed in micelles. This unexpected complex and membrane-mimetic-dependent dynamic behavior indicates that the frequent loss of membrane protein activity in detergents might be related to reduced internal dynamics and that membrane protein activity correlates with lipid flexibility.The outer membrane protein X (OmpX) forms a stable ?-barrel in DPC detergent micelles, DHPC/DMPC bicelles, and DMPC nanodiscs but its dynamics on the pico- to nanosecond and micro- to millisecond timescale differ significantly for the detergent and lipid environments. This dynamic behavior could explain the loss of membrane protein activity frequently observed in detergents.
[NMR paper] Backbone structure of Yersinia pestis Ail determined in micelles by NMR-restrained simulated annealing with implicit membrane solvation.
Backbone structure of Yersinia pestis Ail determined in micelles by NMR-restrained simulated annealing with implicit membrane solvation.
Backbone structure of Yersinia pestis Ail determined in micelles by NMR-restrained simulated annealing with implicit membrane solvation.
J Biomol NMR. 2015 Jul 5;
Authors: Marassi FM, Ding Y, Schwieters CD, Tian Y, Yao Y
Abstract
The outer membrane protein Ail (attachment invasion locus) is a virulence factor of Yersinia pestis that mediates cell invasion, cell attachment and complement...
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07-06-2015 04:35 PM
Backbone structure of Yersinia pestis Ail determined in micelles by NMR-restrained simulated annealing with implicit membrane solvation
Backbone structure of Yersinia pestis Ail determined in micelles by NMR-restrained simulated annealing with implicit membrane solvation
Abstract
The outer membrane protein Ail (attachment invasion locus) is a virulence factor of Yersinia pestis that mediates cell invasion, cell attachment and complement resistance. Here we describe its three-dimensional backbone structure determined in decyl-phosphocholine (DePC) micelles by NMR spectroscopy. The NMR structure was calculated using the membrane function of the implicit solvation potential, eefxPot,...
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07-05-2015 02:07 AM
[NMR paper] Optimizing nanodiscs and bicelles for solution NMR studies of two ?-barrel membrane proteins.
Optimizing nanodiscs and bicelles for solution NMR studies of two ?-barrel membrane proteins.
Related Articles Optimizing nanodiscs and bicelles for solution NMR studies of two ?-barrel membrane proteins.
J Biomol NMR. 2015 Apr;61(3-4):261-74
Authors: Kucharska I, Edrington TC, Liang B, Tamm LK
Abstract
Solution NMR spectroscopy has become a robust method to determine structures and explore the dynamics of integral membrane proteins. The vast majority of previous studies on membrane proteins by solution NMR have been conducted in...
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04-15-2015 04:40 PM
Optimizing nanodiscs and bicelles for solution NMR studies of two β-barrel membrane proteins
Optimizing nanodiscs and bicelles for solution NMR studies of two β-barrel membrane proteins
Abstract
Solution NMR spectroscopy has become a robust method to determine structures and explore the dynamics of integral membrane proteins. The vast majority of previous studies on membrane proteins by solution NMR have been conducted in lipid micelles. Contrary to the lipids that form a lipid bilayer in biological membranes, micellar lipids typically contain only a single hydrocarbon chain or two chains that are too short to form a bilayer. Therefore,...
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02-10-2015 10:56 AM
[NMR paper] Mapping Membrane Protein Backbone Dynamics: A Comparison of Site-Directed Spin Labeling with NMR (15)N-Relaxation Measurements.
Mapping Membrane Protein Backbone Dynamics: A Comparison of Site-Directed Spin Labeling with NMR (15)N-Relaxation Measurements.
Related Articles Mapping Membrane Protein Backbone Dynamics: A Comparison of Site-Directed Spin Labeling with NMR (15)N-Relaxation Measurements.
Biophys J. 2014 Oct 7;107(7):1697-1702
Authors: Lo RH, Kroncke BM, Solomon TL, Columbus L
Abstract
The ability to detect nanosecond backbone dynamics with site-directed spin labeling (SDSL) in soluble proteins has been well established. However, for membrane...
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10-09-2014 07:31 PM
Mapping Membrane Protein Backbone Dynamics: A Comparison of Site-Directed Spin Labeling with NMR 15N-Relaxation Measurements
Mapping Membrane Protein Backbone Dynamics: A Comparison of Site-Directed Spin Labeling with NMR 15N-Relaxation Measurements
Publication date: 7 October 2014
Source:Biophysical Journal, Volume 107, Issue 7</br>
Author(s): Ryan*H. Lo , Brett*M. Kroncke , Tsega*L. Solomon , Linda Columbus</br>
The ability to detect nanosecond backbone dynamics with site-directed spin labeling (SDSL) in soluble proteins has been well established. However, for membrane proteins, the nitroxide appears to have more interactions with the protein surface, potentially hindering the...
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10-08-2014 04:17 AM
[NMR paper] Solution-NMR Characterization of Outer-Membrane Protein A from E. coli in Lipid Bilayer Nanodiscs and Detergent Micelles.
Solution-NMR Characterization of Outer-Membrane Protein A from E. coli in Lipid Bilayer Nanodiscs and Detergent Micelles.
Related Articles Solution-NMR Characterization of Outer-Membrane Protein A from E. coli in Lipid Bilayer Nanodiscs and Detergent Micelles.
Chembiochem. 2014 Apr 1;
Authors: Sušac L, Horst R, Wüthrich K
Abstract
X-ray crystallography and solution NMR of detergent-reconstituted OmpA (outer membrane protein A from E. coli) had shown that this protein forms an eight-stranded transmembrane ?-barrel, but only...
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04-03-2014 12:59 PM
Simultaneous Structure and Dynamics of a Membrane Protein using REDCRAFT: Membrane-bo
Simultaneous Structure and Dynamics of a Membrane Protein using REDCRAFT: Membrane-bound form of Pf1 Coat Protein
Publication year: 2010
Source: Journal of Magnetic Resonance, In Press, Accepted Manuscript, Available online 30 July 2010</br>
Paul, Shealy , Mikhail, Simin , Sang Ho, Park , Stanley J., Opella , Homayoun, Valafar</br>
A strategy for simultaneous study of the structure and internal dynamics of a membrane protein is described using the REDCRAFT algorithm. The membrane-bound form of the Pf1 major coat protein (mbPf1) was used as an example. First, synthetic data is...