Innovation Area - Sensing technology to control quantum systems

NV- qubit for precise sensing of rotational and translational mobilities of active proteins

Diamond sensors dance waltz with ATP synthase

Active proteins control cellular life. The enzyme F_oF₁-ATP synthase provides the energy in the form of the molecule ATP for this purpose, in bacteria, plants, animals, and in humans. As a rotary nanomotor, this enzyme converts an electrochemical membrane potential highly efficiently and rapidly into an energy-rich chemical bond in ATP. This stored energy is then used for cellular processes. The complex random dynamics of three-step motor activity can only be observed in a spatiotemporally separated, single enzyme in the microscope. Quantum sensors such as the NV color center in nanodiamonds can detect three-dimensional motions with the highest precision if they are suitably tethered as markers to active proteins. The QPhoton project now combines the expertise of fabricating NV-doped nanodiamonds and the measurement and analysis techniques of NV spin manipulation with sensitive but rigid coupling chemistry of solids to soft proteins in aqueous solution. The rotational motor of the purified, modified F_oF₁-ATP synthase thus drives the tethered sensor, and the NV quantum sensor reports on all individual steps of the motor. Twenty years after the first joint preliminary considerations for this project, all experimental prerequisites are now in place. The F_oF₁ATP synthase will be prepared in Jena, the coupling chemistry and the quantum sensor module in Stuttgart, and the NV spin manipulation tools in Ulm. The goal is the joint quantum-based investigation of individual active proteins.