Fast-tumbling bicelles constructed from native Escherichia coli lipids
Journal article, 2016

Solution-state NMR requires small membrane mimetic systems to allow for acquiring high-resolution data. At the same time these mimetics should faithfully mimic biological membranes. Here we characterized two novel fast-tumbling bicelle systems with lipids from two Escherichia coli strains. While strain 1 (AD93WT) contains a characteristic E. coli lipid composition, strain 2 (AD93-PE) is not capable of synthesizing the most abundant lipid in E. coli, phosphatidylethanolamine. The lipid and acyl chain compositions were characterized by P-31 and C-13 NMR. Depending on growth temperature and phase, the lipid composition varies substantially, which means that the bicelle composition can be tuned by using lipids from cells grown at different temperatures and growth phases. The hydrodynamic radii of the bicelles were determined from translational diffusion coefficients and NMR spin relaxation was measured to investigate lipid properties in the bicelles. We find that the lipid dynamics are unaffected by variations in lipid composition, suggesting that the bilayer is in a fluid phase under all conditions investigated here. Backbone glycerol carbons are the most rigid positions in all lipids, while head-group carbons and the first carbons of the acyl chain are somewhat more flexible. The flexibility increases down the acyl chain to almost unrestricted motion at its end. Carbons in double bonds and cyclopropane moieties are substantially restricted in their motional freedom. The bicelle systems characterized here are thus found to faithfully mimic E. coli inner membranes and are therefore useful for membrane interaction studies of proteins with E. coli inner membranes by solution-state NMR. (C) 2016 Elsevier B.V. All rights reserved.

Model-free approach

growth-phase

system

Biophysics

1991

mendoza d

1983

v42

chavigny a

micellar-solutions

ejskal eo

Biochemistry & Molecular Biology

Inner membrane

p288

model membrane

pressure resistance

p49

journal of biological chemistry

isotropic bicelles

v8

magnetic-resonance relaxation

trends in biochemical sciences

synthesis

Bicelle

p5323

1965

Dynamics

Lipid composition

cyclopropane fatty-acids

phospholipid bicelles

v266

cardiolipin

translational diffusion

Native lipids

journal of chemical physics

Diffusion

Author

J. Liebau

Stockholm University

P. Pettersson

Stockholm University

P. Zuber

Stockholm University

Candan Ariöz

Chalmers, Biology and Biological Engineering, Chemical Biology

L. Maler

Stockholm University

Biochimica et Biophysica Acta - Biomembranes

0005-2736 (ISSN)

Vol. 1858 9 2097-2105

Subject Categories

Biophysics

DOI

10.1016/j.bbamem.2016.06.008

PubMed

27317394

More information

Latest update

3/1/2018 7