Speaker
Description
Keywords: Bacteria, membrane, lipid profile, DMS-DA6-NH2, mechanism of action, Nuclear Magnetic Resonance
Abstract:
Staphylococcus aureus is a Gram-positive pathogenic bacterium that is resistant to a wide range of antibiotics. DMS-DA6-NH2 (DA6) is a novel antimicrobial peptide (AMP) that has high efficacy on various bacterial strains (1). In vivo 2H solid-state Nuclear Magnetic Resonance (NMR) is used to study AMPs mode of action that disrupt bacterial membranes (2-3). We first determined the bacterial membrane lipid profile (lipids and fatty acids) and then optimised the bacterial culture conditions for lipid labeling with deuterated palmitic acid (PA-d31). 2H in vivo solid-state NMR spectrum under magic-angle spinning is then characterised by a central peak surrounded by rotational bands on both sides, whose spectral moment M² can be measured and is related to membrane rigidity (2). It is then observed that the membrane rigidity decreases progressively when DA6 concentration is increased. These results were compared with those of AMPs whose mode of action are already known (3). It is deduced that the AMP DA6 has a pore effect on S. aureus membrane.
References :
1 Cardon S., Sachon E., Carlier L. , Drujon T. , Walrant A., Aleman-Navarro E. , Martınez-Osorio V., Guianvarch D., Sagan S., Fleury Y. , Marquant R., Piesse C., Rosenstein Y., Auvynet C. , Lacombe C., PLoS ONE 13:e0205727 (2018)
2 Warnet X., Laadhari M. , Arnold A., Marcotte I., and Warschawski D. Biochimica et Biophysica Acta, 1858:146-152 (2016)
3 Laadhari M. , Arnold A. , E. Gravel A. , Separovic F. , Marcotte I. Biochimica et Biophysica Acta 1858:2959-2964 (2016)
| Session | Molecular interactions at the membrane surface |
|---|
