Effect of Cholesterol on the Phase Change of Lipid Membranes by Antimicrobial Peptides

Bulletin of the Korean chemical society

Chul Kim¹  Hyungkeun Choi¹ 

关键词: Magainin 2;    Aurein 3.3;    Pore;    Hexagonal;    2H Solid-state NMR;   

DOI  :  

学科分类：化学（综合）

来源: Korean Chemical Society

【 摘 要 】

Membrane disruption by an antimicrobial peptide (AMP) was investigated by measuring the 2H solid-state nuclear magnetic resonance spectra of 1-palmitoyl-d31-2-oleoyl-sn-glycero-3-phosphatidylcholine (POPC_d31) in mixtures of POPC_d31/cholesterol and either magainin 2 or aurein 3.3 deposited on thin cover-glass plates. The line shapes of the experimental 2H solid-state nuclear magnetic resonance (SSNMR) spectra were best simulated by assuming the coexistence of a mosaic spread of bilayers containing pore structures and a fasttumbling isotropic phase or a hexagonal phase. Within a few days of incubation in a hydration chamber, an isotropic phase and a pore structure were induced by magainin 2, while in case of aurein 3.3 only an isotopic phase was induced in the presence of a bilayer phase. After an incubation period of over 100 days, alignment of the bilayers increased and the amount of the pore structure decreased in case of magainin 2. In contrast with magainin 2, aurein 3.3 induced a hexagonal phase at the peptide-to-lipid ratio of 1/20 and, interestingly, cholesterol was not found in the hexagonal phase induced by aurein 3.3. The experimental results indicate that magainin 2 is more effective in disrupting lipid bilayers containing cholesterol than aurein 3.3.

【 授权许可】

Unknown