Interaction of the K+ channel KcsA with membrane phospholipids as studied by ESI mass spectrometry

FEBS Letters

Demmers, Jeroen A.A.¹  van Dalen, Annemieke¹  Killian, J.Antoinette¹  de Kruijff, Ben¹  Heck, Albert J.R.² 

[1] Department of Biochemistry of Membranes, Center for Biomembranes and Lipid Enzymology, Institute of Biomembranes, Utrecht University, Padualaan 8, 3584 CH Utrecht, The Netherlands;Department of Biomolecular Mass Spectrometry, Bijvoet Center for Biomolecular Research and Utrecht Institute for Pharmaceutical Sciences, Utrecht University, Sorbonnelaan 16, 3584 CA Utrecht, The Netherlands

关键词: Electrospray ionization mass spectrometry;    Protein–lipid interaction;    Lipid bilayer;    DDM;    n-dodecyl-β-D-maltoside;    DEiPC;    1;    2-dieicosenoyl-sn-glycero-3-phosphocholine;    DOPA;    1;    2-dioleyl-sn-glycero-3-phosphate;    DOPC;    1;    2-dioleyl-sn-glycero-3-phosphocholine;    DOPE;    1;    2-dioleyl-sn-glycero-3-phosphoethanolamine;    DOPG;    1;    2-dioleyl-sn-glycero-3-phosphoglycerol;    DPoPC;    1;    2-dipalmitoleoyl-sn-glycero-3-phosphocholine;    ESI-MS;    electrospray ionization mass spectrometry;    LUVETs;    large unilamellar vesicles prepared by extrusion;    m/z;    mass-to-charge ratio;    PA;    phosphatidic acid;    PC;    phosphatidylcholine;    PE;    phosphatidylethanolamine;    PG;    phosphatidylglycerol;    TFE;    2;    2;    2-trifluoroethanol;   

DOI  :  10.1016/S0014-5793(03)00282-5

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

In this study we have used electrospray ionization mass spectrometry (ESI-MS) to investigate interactions between the bacterial K⁺ channel KcsA and membrane phospholipids. KcsA was reconstituted into lipid vesicles of variable lipid composition. These vesicles were directly analyzed by ESI-MS or mixed with trifluoroethanol (TFE) before analysis. In the resulting mass spectra, non-covalent complexes of KcsA and phospholipids were observed with an interesting lipid specificity. The anionic phosphatidylglycerol (PG), and, to a lesser extent, the zwitterionic phosphatidylethanolamine (PE), which both are abundant bacterial lipids, were found to preferentially associate with KcsA as compared to the zwitterionic phosphatidylcholine (PC). These preferred interactions may reflect the differences in affinity of these phospholipids for KcsA in the membrane.

【 授权许可】

Unknown