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PubMed · 16492058

Observing a molecular knife at work.

Xiaoyun Chen·Haizhong Tang·Mark A Even·Jie Wang·Gregory N Tew·Zhan Chen
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Abstract

Sum frequency generation (SFG) vibrational spectroscopy has been employed to study the molecular interactions between a single substrate supported lipid bilayer and an amphiphilic antibiotic compound 1, with a design based on the common structural motif of natural antimicrobial peptides. The interfacial sensitivity of SFG allows real-time in situ monitoring of ordering changes in both leaflets of the bilayer and orientation of 1 simultaneously. A critical concentration of about 0.8 microg/mL of 1 is found, above which the inner leaflet of the bilayer is significantly perturbed. This concentration corresponds well to the minimum inhibition concentration of 1 that is obtained from bacterial experiments. Orientation of 1 in the bilayer is shown to be perpendicular to the bilayer surface, in agreement with simulation results. SFG can be developed into a very informative technique for studying the cell membrane and the interactions of membrane-active molecules.

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AmidesAnti-Infective AgentsBiomimetic MaterialsComputer SimulationHydrophobic and Hydrophilic InteractionsLipid BilayersModels, MolecularPeptidesPhosphatidylglycerolsSpectrophotometry, InfraredJournal ArticleResearch Support, U.S. Gov't, Non-P.H.S.

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Xiaoyun Chen, Haizhong Tang, Mark A Even, Jie Wang, Gregory N Tew, Zhan Chen. 2006-03-01. Observing a molecular knife at work.. https://doi.org/10.1021/ja057029t

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