Lipid membrane binding of NK‐lysin

FEBS Letters

Goormaghtigh, Erik¹  Liepinsh, Edvards²  Ruysschaert, Jean-Marie¹  Homblé, F¹  Andersson, Mats²  Otting, Gottfried² 

[1] Laboratoire de Chimie Physique des Macromolécules aux Interfaces (LCPMI), Université Libre de Bruxelles, B-1050 Brussels, Belgium;Department of Medical Biochemistry and Biophysics, Karolinska Institute, S-171 77 Stockholm, Sweden

关键词: NK-lysin;    Membrane binding;    Pore formation;    Fourier transform infrared spectroscopy;    ATR;    attenuated total reflection;    CD;    circular dichroism;    EDTA;    ethylene-diamine-tetraacetate;    FTIR spectroscopy;    Fourier transform infrared spectroscopy;    LUV;    large unilamellar vesicle;    NK;    natural killer;    SP-B;    surfactant protein B;   

DOI  :  10.1016/S0014-5793(98)00261-0

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

The membrane-binding properties and pore-forming potential of the tumor-lysing and antibacterial polypeptide NK-lysin were investigated. Fluorescence quenching experiments show a drastic change of accessibility to Trp⁵⁸ in solution and in association with a lipid membrane. Calcein release from large unilamellar vesicles and fluctuating conductivity observed across a planar lipid bilayer of asolectin show that NK-lysin renders lipid bilayers permeable in a transient fashion, indicating a non-specific lipid interaction as the mechanism underlying the biological activity. FTIR experiments show the same amount and type of regular secondary structure of NK-lysin in the membrane as in aqueous solution and exclude a structural rearrangement into a set of parallel or antiparallel α-helices as the predominant conformation. The molecular mechanism of the membrane-destabilizing effect of NK-lysin is discussed.

【 授权许可】

Unknown