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Liposomal cargo unloading induced by pH-sensitive peptides.

H-M Lee·J Chmielewski
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Abstract

Amphiphilic peptides designed to have a pH-dependent conformational change and membrane activity are described. At physiologic pH, the peptides would exist in a random coil conformation, but at endosomal pH values they would switch to amphiphilic alpha-helices, disrupt membranes, and release liposomal contents. A series of peptides have been investigated that contain a high percentage of Glu residues for the pH-induced conformational switch, and Leu residues for optimal lipid binding. Circular dichroism (CD) results in aqueous and liposomal environments were performed and demonstrate a pH-dependent shift to helicity upon acidification. Liposomal release data at neutral and acidic pH, also document the success of this design strategy.

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Binding SitesCircular DichroismDrug Delivery SystemsHydrogen-Ion ConcentrationLiposomesPeptidesProtein ConformationJournal Article

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H-M Lee, J Chmielewski. 2005. Liposomal cargo unloading induced by pH-sensitive peptides.. https://doi.org/10.1111/j.1399-3011.2005.00229.x

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