Membrane potential-dependent binding of polysialic acid to lipid monolayers and bilayers

Cellular & Molecular Biology Letters

Teresa Janas¹  Tadeusz Janas¹  Monika Kowalska¹  Karolina Sapoń¹  Krzysztof Nowotarski¹ 

[1] Department of Biotechnology and Molecular Biology, University of Opole, Opole, Poland$$

关键词: Polysialic acid;    Polyanion;    Lipid bilayer;    Lipid monolayer;    Membrane potential;    Liposome;    DPH anisotropy;   

DOI  :  10.2478/s11658-013-0108-x

学科分类：分子生物学，细胞生物学和基因

来源: Uniwersytet Wroclawski * Wydzial Biotechnologii / University of Wroclaw, Faculty of Biotechnology

【 摘 要 】

Polysialic acids are linear polysaccharides composed of sialic acid monomers. These polyanionic chains are usually membrane-bound, and are expressed on the surfaces of neural, tumor and neuroinvasive bacterial cells. We used toluidine blue spectroscopy, the Langmuir monolayer technique and fluorescence spectroscopy to study the effects of membrane surface potential and transmembrane potential on the binding of polysialic acids to lipid bilayers and monolayers. Polysialic acid free in solution was added to the bathing solution to assess the metachromatic shift in the absorption spectra of toluidine blue, the temperature dependence of the fluorescence anisotropy of DPH in liposomes, the limiting molecular area in lipid monolayers, and the fluorescence spectroscopy of oxonol V in liposomes. Our results show that both a positive surface potential and a positive transmembrane potential inside the vesicles can facilitate the binding of polysialic acid chains to model lipid membranes. These observations suggest that these membrane potentials can also affect the polysialic acid-mediated interaction between cells.

【 授权许可】

Unknown