In cells, metabolic reaction networks orchestrate the supply, regeneration and removal of energy. Ultimately, those energy modules are responsible for the flawless performance of all cellular functions over time, and thus for the maintenance of life. In contrast, the long-term performance of man-made non-equilibrium systems is often limited by the limited availability of fuel molecules or the synthesis of building blocks that require fuel, either in the form of ATP or electrochemical ion gradients.
We have developed synthetic vesicle systems that recycle ATP for periods at least an order of magnitude longer than ever reported, secrete ATP to activate enzymatic reactions, supply fuel for secondary vesicles or synthesize biochemical building blocks followed by secretion of these molecules. The synthesis of ATP is based on deamination of amino acids and secretion of end products to keep the reaction network out of equilibrium. Similarly, we have developed vesicles for long-term generation of an electrochemical proton gradient, which is based on a decarboxylation reaction and electrogenic antiport of precursors and products of the reaction. We have tested both energy modules under different load conditions (energy consumption) and foresee further development into advanced biosensing or fuel supply for biomolecular devices or synthetic biology.
