MIIT Key Laboratory of Critical Materials Technology for New Energy Conversion and Storage, School of Chemistry and Chemical Engineering, Harbin Institute of Technology, Harbin, 150001, China.
Nat Commun. 2024 Oct 2;15(1):8517. doi: 10.1038/s41467-024-52802-8.
Oil-in-water emulsion is a system with extensive applications in foods, cosmetics and coating industries, and it could also be designed into an artificial lipid droplet in recent works. However, the insights into the biophysical dynamic behaviors of such artificial lipid droplets are lacking. Here, we reveal an enzymatic reaction triggered endocytosis-like behavior in the oil-in-water emulsion lipid droplets. A thermodynamically favored recruitment of lipases onto the membrane of the droplets is demonstrated. We confirm that the hydrolysis of tributyrin by lipases can decrease the interfacial tension and increase the compressive force on the membrane, which are the two main driving forces for triggering the endocytosis-like behavior. The endocytosis-like behavior induced various emerging functionalities of the lipid droplets, including proteins, DNA or inorganic particles being efficiently sequestered into the oil droplet with reversible release as well as enhanced cascade enzymatic reaction. Overall, our studies are expected to open up a way to functionalize oil-in-water emulsions capable of life-inspired behaviors and tackle emerging challenges in bottom-up synthetic biology, revealing the unknown dynamic behaviors of lipid droplets in living organisms.
水包油乳液在食品、化妆品和涂料行业有广泛的应用，在最近的研究中，它也可以被设计成人工脂滴。然而，人们对这种人工脂滴的生物物理动态行为缺乏了解。在这里，我们揭示了水包油乳液脂滴中酶反应触发的内吞样行为。证明了脂肪酶在脂滴膜上的热力学有利招募。我们证实，脂肪酶对三丁酸甘油酯的水解可以降低界面张力并增加对膜的压缩力，这是触发内吞样行为的两个主要驱动力。内吞样行为诱导了脂滴的各种新出现的功能，包括蛋白质、DNA 或无机颗粒被有效地隔离到油滴中，并具有可逆释放以及增强级联酶反应的功能。总的来说，我们的研究有望为能够模仿生命行为的水包油乳液开辟一条功能化途径，并解决自下而上合成生物学中的新兴挑战，揭示生物体内脂滴未知的动态行为。
