Department of Biosystems Engineering and Soil Science, University of Tennessee, Knoxville, TN 37996-4531, USA.
Department of Biosystems Engineering and Soil Science, University of Tennessee, Knoxville, TN 37996-4531, USA.
Biochim Biophys Acta Biomembr. 2018 Feb;1860(2):624-632. doi: 10.1016/j.bbamem.2017.11.005. Epub 2017 Nov 12.
Antimicrobial peptides effectively kill antibiotic-resistant bacteria by forming pores in prokaryotes' biomembranes via penetration into the biomembranes' interior. Bicontinuous microemulsions, consisting of interdispersed oil and water nanodomains separated by flexible surfactant monolayers, are potentially valuable for hosting membrane-associated peptides and proteins due to their thermodynamic stability, optical transparency, low viscosity, and high interfacial area. Here, we show that bicontinuous microemulsions formed by negatively-charged surfactants are a robust biomembrane mimetic system for the antimicrobial peptide melittin. When encapsulated in bicontinuous microemulsions formed using three-phase (Winsor-III) systems, melittin's helicity increases greatly due to penetration into the surfactant monolayers, mimicking its behavior in biomembranes. But, the threshold melittin concentration required to achieve these trends is lower for the microemulsions. The extent of penetration was decreased when the interfacial fluidity of the microemulsions was increased. These results suggest the utility of bicontinuous microemulsions for isolation, purification, delivery, and host systems for antimicrobial peptides.
抗菌肽通过穿透生物膜内部在原核生物的生物膜中形成孔来有效杀死抗药性细菌。双连续微乳液由分散在柔性表面活性剂单层之间的互穿油和水纳米域组成，由于其热力学稳定性、光学透明度、低粘度和高界面面积，对于容纳与膜相关的肽和蛋白质具有潜在的价值。在这里，我们表明，由带负电荷的表面活性剂形成的双连续微乳液是一种用于抗菌肽蜂毒素的稳健的生物膜模拟系统。当包封在使用三相（Winsor-III）系统形成的双连续微乳液中时，由于穿透到表面活性剂单层中，蜂毒素的螺旋度大大增加，模拟了其在生物膜中的行为。但是，对于微乳液来说，实现这些趋势所需的最小蜂毒素浓度更低。当微乳液的界面流变性增加时，穿透的程度降低。这些结果表明双连续微乳液在隔离、纯化、输送和抗菌肽的宿主系统方面具有实用性。
