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Divalent metal ion triggered activity of a synthetic antimicrobial in cardiolipin membranes.

ABSTRACT: One member of a prototypical class of antimicrobial oligomers was used to study pore formation in cardiolipin-rich membranes. Both vesicle dye-leakage assays and small-angle X-ray scattering were used to study bilayer remodeling. The results indicate that the presence of negative intrinsic curvature lipids is essential for pore formation by this class of molecules: In Gram-positive bacteria, cardiolipin and divalent metal cations like Ca(2+) and Mg(2+) are needed. This is consistent with the role of phosphatidylethanolamine (PE) lipid in Gram-negative bacteria, where antimicrobial activity is dependent on the negative intrinsic curvature of PE rather than a specific interaction with PE.

SUBMITTER: Som A

PROVIDER: S-EPMC3692289 | biostudies-other | 2009 Oct

REPOSITORIES: biostudies-other

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Divalent metal ion triggered activity of a synthetic antimicrobial in cardiolipin membranes.

Som Abhigyan A Yang Lihua L Wong Gerard C L GC Tew Gregory N GN

Journal of the American Chemical Society 20091001 42

One member of a prototypical class of antimicrobial oligomers was used to study pore formation in cardiolipin-rich membranes. Both vesicle dye-leakage assays and small-angle X-ray scattering were used to study bilayer remodeling. The results indicate that the presence of negative intrinsic curvature lipids is essential for pore formation by this class of molecules: In Gram-positive bacteria, cardiolipin and divalent metal cations like Ca(2+) and Mg(2+) are needed. This is consistent with the rol ...[more]

PMID: 19807082

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