β2 glycoprotein I (β2GPI) is a soluble protein that participates in blood coagulation, clearance of apoptotic bodies and generation of antigens in antiphospholipid syndrome among many other functions. We studied the aggregates formed by β2GPI with the anionic phospholipids palmitoyloleoylphosphatidyl glycerol, dimyristoylphosphatidyl glycerol, dipalmitoylphosphatidyl glycerol and cardiolipin using small angle X-ray scattering. The complexes obtained in a medium containing 0.01 M NaCl showed Bragg peaks up to the sixth order in a well-defined integer sequence indicating the presence of a lamellar stacking with a periodicity of 17.8 nm and with largely reduced membrane fluctuations. Modeling the complex signal allowed us to conclude that the coherence length was only two bilayers and that about 15% of the total surface was actually stacked. The space between bilayers allows accommodating an extended β2GPI molecule making a bridge between the interacting bilayers. The interactions between membranes mediated by β2GPI was favored when the membranes were in the liquid crystalline state.

β2 糖蛋白 I (β2GPI) 是一种可溶性蛋白，在抗磷脂综合征中参与凝血、清除凋亡小体和抗原生成等多种功能。我们使用小角 X 射线散射研究了 β2GPI 与阴离子磷脂棕榈酰油酰磷脂酰甘油、二肉豆蔻酰磷脂酰甘油、二棕榈酰磷脂酰甘油和心磷脂形成的聚集体。在含有 0.01 M NaCl 的介质中获得的复合物在明确定义的整数序列中显示出高达六阶的布拉格峰，表明存在周期性为 17.8 nm 的层状堆叠，并且膜波动大大减少。对复杂信号进行建模使我们能够得出结论，相干长度仅为两个双层，并且总表面的大约 15% 实际上是堆叠的。双层之间的空间允许容纳扩展的 β2GPI 分子，从而在相互作用的双层之间架起桥梁。当膜处于液晶状态时，β2GPI 介导的膜之间的相互作用是有利的。