Engineering Approaches to Biomolecular Motors

Engineering Approaches to Biomolecular Motors: From in vitro to in vivo Poster Abstracts

2-POS Board 2 Maximizing Irreversibility and Minimizing Energy Dissipation for Simple Models of Mechanochemical Machines Aidan I. Brown , David A. Sivak. Simon Fraser University, Burnaby, BC, Canada. Driven reactions and processes at microscopic scales must overcome fluctuations to proceed forwards more than they go in reverse. It is well known that some free energy dissipation is required to achieve irreversible forward progress, but the detailed relationship between irreversibility and free energy dissipation is not well understood. We present results for the irreversibility-dissipation relationship of a model system which captures the basic physics of energy storage. Such a system can represent many examples – ATP synthase completing unfavourable rotations to synthesize ATP, linear walking motors changing conformation prior to a power stroke, and viral packing motors translocating against the pressure of a polymer trying to escape. Our analysis reveals that reactions which do not carry a system far beyond the energy storage step can achieve equal irreversibility while reducing dissipation. Our results also suggest scenarios where a system must pay a higher dissipation cost for a relatively low irreversibility. We discuss how our investigation points towards general principles of microscopic machine operation and process design.

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