Novel antimicrobial agents are focused to interact with the bacterial membrane whose lipid composition (number and position of unsaturations and lipid headgroup) is adapted according to environmental signals. The anticipation of the adapted membrane properties is of high relevance to increase the targetability of such drugs. Herein, natural lipids extracted from Escherichia coli -phosphatidylethanolamine (PE), phosphatidylglycerol (PG) and cardiolipin (CL)- are used to form biomimetic membranes constituted by several PE:lipid ratios using the Langmuir and Langmuir-Blodgett techniques. The use of these techniques and the natural myriad of each lipid structures that constitute the biological E.coli membrane establishes a simple and reproducible model to evaluate the lipid-lipid interactions. PE and PG present similar shape and size, thus establish ideal and fluid -liquid expanded (LE) state - mixtures, whereas the differences between PE and CL motivate the formation of non-ideal and fluid (LE state) mixtures. The same physical state and the minor differences in elasticity (differences in the inverse of the compressibility modulus < 15 mN·m⁻¹) between both systems regardless the PE content in the (PE:lipid) mixture suggest that the changes in the lipid composition influence the membrane proteins function rather than affecting the rigidity of the bacterial membrane.

新型抗微生物剂致力于与细菌膜相互作用，该细菌膜的脂质组成（不饱和基团的数量和位置以及脂质头基）根据环境信号进行了调整。预期适应的膜特性与增加此类药物的靶向性具有高度相关性。在本文中，使用朗格缪尔（Langmuir）和朗缪尔-布洛杰特（Langmuir-Blodgett）技术，使用从大肠杆菌中提取的天然脂质-磷脂酰乙醇胺（PE），磷脂酰甘油（PG）和心磷脂（CL）-形成由几种PE∶脂质比率构成的仿生膜。这些技术的使用以及构成生物大肠杆菌的每个脂质结构的天然无数种膜建立了一个简单且可复制的模型来评估脂质-脂质相互作用。PE和PG呈现相似的形状和大小，因此建立了理想的流体-液体膨胀（LE）状态的混合物，而PE和CL之间的差异促使形成了非理想和流体（LE状态）的混合物。两个系统之间的相同物理状态和较小的弹性差异（可压缩模量的倒数<15 mN·m ^-1），与（PE：脂质）混合物中的PE含量无关，表明脂质组成的变化影响膜蛋白的功能而不是影响细菌膜的刚度。