As we have been discussing, it might be true that circularization of protein enhances its durability in some cases. Thus it can be said this method would provide more “User-Friendly” proteins in terms of making it possible to try new reaction conditions. It might bring some breakthroughs to chemical industry.
Then, we come to the new question - how can we use the tech of circularization in vivo? Especially in the field of synthetic biology? Giving brief looks to our beautiful bodies, we can find many examples how circularization contributes to maintain our system; insulin and other hormones have the circled structures during their “Pro” conditions. It may suggest us that circularization would be one of the means to regulate the activity of proteins in the living cells.
In order to reveal the capability of the circularization, we suggest following future works to be done. Firstly we need to consider whether it is possible to “silence” the protein function. If it is, does the location where circularization takes place affect the silencing? Secondly we need to check that termination of circle structure - maybe using proteases - brings its ability to the protein. Finally we have to find or design the specific protease to bring the protein activity again. These are main remaining questions to be solved for advanced usage of circularization of protein in our field. Surely it must be a tough way to go, but it will bring a new regulating system in the cell.