Department of Chemical Engineering, University of Florida 1006 Center Drive, FL 32669, USA.
Soft Matter. 2023 May 10;19(18):3273-3280. doi: 10.1039/d3sm00096f.
In this study, we investigate the changes in the permeability of the recombinant fusion protein vesicles with different membrane structures as a function of solution temperature. The protein vesicles are self-assembled from recombinant fusion protein complexes composed of an mCherry fused with a glutamic acid-rich leucine zipper and a counter arginine-rich leucine zipper fused with an elastin-like polypeptide (ELP). We have found that the molecular weight cut-off (MWCO) of the protein vesicle membranes varies inversely with solution temperature by monitoring the transport of fluorescent-tagged dextran dyes with different molecular weights. The temperature-responsiveness of the protein vesicle membranes is obtained from the lower critical solution temperature behavior of ELP in the protein building blocks. Consequently, the unique vesicle membrane structures with different single-layered and double-layered ELP organizations impact the sensitivity of the permeability responses of the protein vesicles. Single-layered protein vesicles with the ELP domains facing the interior show more drastic permeability changes as a function of temperature than double-layered protein vesicles in which ELP blocks are buried inside the membranes. This work about the temperature-responsive membrane permeability of unique protein vesicles will provide design guidelines for new biomaterials and their applications, such as drug delivery and synthetic protocell development.
在这项研究中，我们研究了不同膜结构的重组融合蛋白囊泡的通透性随溶液温度的变化。这些蛋白囊泡是由重组融合蛋白复合物自组装而成的，这些复合物由一个与谷氨酸丰富的亮氨酸拉链融合的 mCherry 和一个与弹性蛋白样多肽（ELP）融合的精氨酸丰富的亮氨酸拉链组成。我们发现，通过监测不同分子量的荧光标记葡聚糖染料的传输，蛋白囊泡膜的分子量截止值（MWCO）随溶液温度呈反比变化。蛋白囊泡膜的温度响应性来自于蛋白构建块中 ELP 的下临界溶液温度行为。因此，具有不同单层和双层 ELP 组织的独特囊泡膜结构会影响蛋白囊泡通透性响应的灵敏度。具有内部朝向 ELP 结构域的单层蛋白囊泡的通透性变化比双层蛋白囊泡更为剧烈，因为后者的 ELP 结构域被埋在膜内。这项关于独特蛋白囊泡的温度响应性膜通透性的工作将为新的生物材料及其应用（如药物传递和合成原细胞的发展）提供设计指南。
