含有修饰SpA的重组生物膜的表征

Characterization of an Artificial Membrane Containing Modified Staphylococcal Protein A

通过ＬＢ膜技术将硬脂酸酯修饰的ＳｐＡ嵌入到气液界面的磷脂膜中，并沉积于疏水化石英表面形成重组双层生物膜。此重组膜可作为免疫球蛋白（ＩｇＧ）的通用诱导膜。结果表明，修饰ＳｐＡ表面硬脂酸数目的多少是影响该蛋白构象变化的主要原因。当其嵌入到磷脂单分子膜中时，膜中蛋白质密度增加，且呈现良好的成膜特性。重组膜中ＳｐＡ的活性下降与硬脂酸的修饰及ＳｐＡ在膜中嵌入作用有关。本文还讨论了膜中结合ＩｇＧ的状态。

A method is described for incorporation of water- solube SpA into phospholipid monolayerusing covalent SpA-stearate conjugates,and then transferring the monolayer on the pre-treated silicasurface to form a SpA containing membrane, The membrane eould be used as a general inducing filmfor IgG, The results show that the lipid modification degree is the main reason for influencing confor- mation changes of the protein, When the modified SpA is incorporated into the DPPA monotayer , theprotein density in the membrane is proportional to the lipid coupling degree. The IgG binding ability ofmodified SpA decreases with the increase of the lipid coupling degree. The ability further decreaseswhen modified SpA is incorporated in the membrane, which might be caused by manipulation. Thestatus of bound IgG in the membrane is also discussed.