Enhanced Diffusion of Molecular Catalase

Active matter, which focuses on ensembles of self-propelled elements, has shown unique emergent activities making them excellent candidates for novel materials of the future. One of these emergent activities is how active materials couple together to harvest energy to perform work from athermal noise. Biological systems do this routinely to perform work used in cell division and cell motility. Enzymes are non-equilibrium proteins that use substrates and release products asymmetrically. Recent work has shown that enzymes, such as catalase, urase, and adolase, can causes enhanced diffusion in bulk depending on the substrate concentration. We are using catalase, an common asymmetric enzyme, and its substrate, hydrogen peroxide, as the basic model system, to demonstrate the work-harvesting from noisy on molecular-scale. Using TIRF microscopy, we can measure the diffusion of individual catalase molecules to test for enhanced diffusion as a function of substrate concentration to check if diffusion of individual molecules is enhanced, or if the phenomena is purely an ensemble activity. This work will pave the way to determining the mechanism for the enhanced diffusion and ultimately enable a system that can harness the non-equilibrium noise of enzymes into mechanical work.