Powered by Indico
v3.2.8
Living matter in action, at the smallest length scale epitomized by biological motors, operates in nonequilibrium steady states(NESS). In NESS, the detailed balance is broken such that non-vanishing energy and material currents continuously flow in and out of the system. Together with the microscopic underpinnings underlying the functions of individual motors, I am interested in quantifying how energy, information, and material balance in biological systems contributes to the emergence of cellular organizations. Among others, particular interest of our group lies in the world smallest nano-machines, molecular motors that consume chemical free energy of ATP to rectify its random thermal fluctuations into uni-directional movement along cytoskeletal filaments. From the perspective of thermodynamics, the energetic cost of determining the dynamical information increases with the precision being pursued. This notion of trade-off between the energetic cost and the statistical error of an observable for dissipative processes in nonequilibrium steady state has recently been formulated in the name of thermodynamic uncertainty relation. Here we use the principle underlying the uncertainty relation to quantify the transport efficiency of molecular motors for varying ATP concentration ([ATP]) and external load(f). Our analyses of experimental data find that transport efficiencies of the motors studied here are semi-optimized under the cellular condition. The efficiency is significantly deteriorated for a mutant, which underscores the importance of molecular structure. It is remarkable to recognize that, among many possible directions for optimization, biological motors have evolved to optimize the transport efficiency in particular.