title: Fluctuating currents in stochastic thermodynamics. II. Energy conversion and nonequilibrium response in kinesin models.
abstract: Unlike macroscopic engines, the molecular machinery of living cells is strongly affected by fluctuations. Stochastic thermodynamics uses Markovian jump processes to model the random transitions between the chemical and configurational states of these biological macromolecules. A recently developed theoretical framework [A. Wachtel, J. Vollmer, and B. Altaner, Phys. Rev. E 92, 042132 (2015)] provides a simple algorithm for the determination of macroscopic currents and correlation integrals of arbitrary fluctuating currents. Here we use it to discuss energy conversion and nonequilibrium response in different models for the molecular motor kinesin. Methodologically, our results demonstrate the effectiveness of the algorithm in dealing with parameter-dependent stochastic models. For the concrete biophysical problem our results reveal two interesting features in experimentally accessible parameter regions: the validity of a nonequilibrium Green-Kubo relation at mechanical stalling as well as a negative differential mobility for superstalling forces.
authors.affiliation: Department of Dynamics of Complex Fluids (DCF), Max Planck Institute for Dynamics and Self-Organization (MPI DS), Am Fassberg 17, 37077 Göttingen, Germany.|Institute for Nonlinear Dynamics, Faculty of Physics, Georg-August University Göttingen, 37077 Göttingen, Germany.
authors.forename: Bernhard
authors.initials: B
authors.lastname: Altaner
authors.affiliation: Department of Dynamics of Complex Fluids (DCF), Max Planck Institute for Dynamics and Self-Organization (MPI DS), Am Fassberg 17, 37077 Göttingen, Germany.|Complex Systems and Statistical Mechanics, Physics and Materials Science Research Unit, University of Luxembourg, Luxembourg.
authors.forename: Artur
authors.initials: A
authors.lastname: Wachtel
authors.affiliation: Department of Dynamics of Complex Fluids (DCF), Max Planck Institute for Dynamics and Self-Organization (MPI DS), Am Fassberg 17, 37077 Göttingen, Germany.|Institute for Nonlinear Dynamics, Faculty of Physics, Georg-August University Göttingen, 37077 Göttingen, Germany.
authors.forename: Jürgen
authors.initials: J
authors.lastname: Vollmer
mesh_terms: D000255:Adenosine Triphosphate / Q000378:metabolism; D001696:Biomechanical Phenomena; D004058:Diffusion; D006868:Hydrolysis; D016547:Kinesins / Q000378:metabolism*; D008390:Markov Chains; D008954:Models, Biological; D013269:Stochastic Processes; D013816:Thermodynamics
chemical_list: D000255:Adenosine Triphosphate; D016547:Kinesins