Department of Biomedical Engineering, Faculty of Fundamental Problems of Technology, Wroclaw University of Science and Technology, Wroclaw, Poland.
J. Heyrovský Institute of Physical Chemistry, Czech Academy of Sciences, v.v.i., Prague, Czech Republic.
Biochim Biophys Acta Biomembr. 2017 Dec;1859(12):2289-2296. doi: 10.1016/j.bbamem.2017.08.015. Epub 2017 Aug 26.
The tear film is a thin multilayered structure covering the cornea. Its outermost layer is a lipid film underneath of which resides on an aqueous layer. This tear film lipid layer (TFLL) is itself a complex structure, formed by both polar and nonpolar lipids. It was recently suggested that due to tear film dynamics, TFLL contains inhomogeneities in the form of polar lipid aggregates. The aqueous phase of tear film contains lachrymal-origin proteins, whereby lysozyme is the most abundant. These proteins can alter TFLL properties, mainly by reducing its surface tension. However, a detailed nature of protein-lipid interactions in tear film is not known. We investigate the interactions of lysozyme with TFLL in molecular details by employing coarse-grained molecular dynamics simulations. We demonstrate that lysozyme, due to lateral restructuring of TFLL, is able to penetrate the tear lipid film embedded in inverse micellar aggregates.
泪膜是覆盖角膜的一层薄的多层结构。它的最外层是一层脂质膜，其下是一层水层。这个泪膜脂质层（TFLL）本身就是一个复杂的结构，由极性和非极性脂质组成。最近有人提出，由于泪膜动力学，TFLL 中含有以极性脂质聚集物形式存在的不均匀性。泪膜的水相含有泪液来源的蛋白质，其中溶菌酶最为丰富。这些蛋白质可以改变 TFLL 的性质，主要是通过降低其表面张力。然而，泪膜中蛋白质-脂质相互作用的详细性质尚不清楚。我们通过使用粗粒化分子动力学模拟来研究溶菌酶与 TFLL 的分子相互作用。我们证明，由于 TFLL 的横向重构，溶菌酶能够穿透嵌入反向胶束聚集体中的泪液脂质膜。
