Control of Allosteric Protein Electrochemical Switches with Biomolecular and Electronic Signals

The construction of allosteric protein switches is a key goal of synthetic biology. Such switches can be compiled into signaling systems mimicking information and energy processing systems of living organisms. Here we demonstrate construction of a biocatalytic electrode functionalized with a recombinant chimeric protein between pyrroloquinoline quinone-dependent glucose dehydrogenase and calmodulin. This electrode could be activated by calmodulin-binding peptide and showed a high bioelectrocatalytic current (ca. 300 μA) due to efficient direct electron transfer. In order to expand the types of inputs that can be used to activate the developed electrode, we constructed a caged version of calmodulin-binding peptide that could be proteolytically uncaged using a protease of choice. Finally, the complexity of the switchable bioelectrochemical system was further increased by the use of almost any kind of molecule/biomolecule or electronic signal, unequivocally proving the orthogonality of the aforementioned system.