Dynamics of Protein-Confined Water in Polymer Vesicles: A Feasibility Study

When we confine water in extremely small spaces it starts to move extremely slowly. This behaviour is critical to helping biological molecules like proteins function normally. We have developed a system in which we can place very large amounts of protein in hollow containers called vesicles, which can be as small as 50 nanometres. When we encapsulate special types of proteins called enzymes, which help the body perform chemical reactions, we find the enzymes work faster when they're inside the vesicles than they do when they're outside it. Even more remarkably, we find that when we heat up our vesicles, enzymes inside the vesicles continue to work at temperatures that would normally break them. We think we can explain our findings by studying how changing the amount of protein in a vesicle changes the way the water inside the vesicle moves.