Journal
BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES
Volume 1828, Issue 2, Pages 614-622Publisher
ELSEVIER SCIENCE BV
DOI: 10.1016/j.bbamem.2012.09.011
Keywords
Membrane interaction; Polymyxin B; Polyhydroxylated fullerene nanoparticle; Cetyltrimethylammonium chloride; Marennine-like pigment; Nuclear magnetic resonance
Categories
Funding
- Natural Sciences and Engineering Research Council (NSERC) of Canada
- Fonds de recherche du Quebec - Nature et Technologies (FRQNT)
- Groupe de Recherche Axe sur la Structure des Proteines (GRASP)
- Reseau Aquaculture Quebec (RAQ)
- NSERC
- Canada Foundation for Innovation (CFI)
Ask authors/readers for more resources
Solid-state nuclear magnetic resonance (NMR) is a useful tool to probe the organization and dynamics of phospholipids in bilayers. The interactions of molecules with membranes are usually studied with model systems; however, the complex composition of biological membranes motivates such investigations on intact cells. We have thus developed a protocol to deuterate membrane phospholipids in Escherichia coli without mutating to facilitate H-2 solid-state NMR studies on intact bacteria. By exploiting the natural lipid biosynthesis pathway and using perdeuterated palmitic acid, our results show that 76% deuteration of the phospholipid fatty acid chains was attained. To verify the responsiveness of these membrane-deuterated E. coli, the effect of known antimicrobial agents was studied. H-2 solid-state NMR spectra combined to spectral moment analysis support the insertion of the antibiotic polymyxin B lipid tail in the bacterial membrane. The use of membrane-deuterated bacteria was shown to be important in cases where antibiotic action of molecules relies on the interaction with lipopolysaccharides. This is the case of fullerenol nanoparticles which showed a different effect on intact cells when compared to dipalmitoylphosphatidylcholine/dipalmitoylphosphatidylglycerol membranes. Our results also suggest that membrane rigidification could play a role in the biocide activity of the detergent cetyltrimethyammonium chloride. Finally, the deuterated E. coli were used to verify the potential antibacterial effect of a marennine-like pigment produced by marine microalgae. We were able to detect a different perturbation of the bacteria membranes by intra- and extracellular forms of the pigment, thus providing valuable information on their action mechanism and suggesting structural differences. (C) 2012 Elsevier B.V. All rights reserved.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available