Fast-tumbling bicelles constructed from native Escherichia coli lipids
Artikel i vetenskaplig tidskrift, 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.

growth-phase

v266

Model-free approach

Native lipids

pressure resistance

translational diffusion

Lipid composition

chavigny a

synthesis

v8

journal of chemical physics

cardiolipin

cyclopropane fatty-acids

system

journal of biological chemistry

Bicelle

Biochemistry & Molecular Biology

isotropic bicelles

v42

magnetic-resonance relaxation

p49

ejskal eo

1991

phospholipid bicelles

p288

trends in biochemical sciences

Diffusion

Dynamics

1983

1965

Biophysics

model membrane

Inner membrane

p5323

micellar-solutions

mendoza d

Författare

J. Liebau

Stockholms universitet

P. Pettersson

Stockholms universitet

P. Zuber

Stockholms universitet

Candan Ariöz

Chalmers, Biologi och bioteknik, Kemisk biologi

L. Maler

Stockholms universitet

Biochimica et Biophysica Acta - Biomembranes

0005-2736 (ISSN)

Vol. 1858 2097-2105

Ämneskategorier

Biofysik

DOI

10.1016/j.bbamem.2016.06.008

PubMed

27317394