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arXiv · 1708.07454

Tension and chemical efficiency of Myosin-II motors

Pieter Baerts·Christian Maes·Jiří Pešek·Herman Ramon
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Abstract

Recent experiments demonstrate that molecular motors from the Myosin II family serve as cross-links inducing active tension in the cytoskeletal network. Here we revise the Brownian ratchet model, previously studied in the context of active transport along polymer tracks, in setups resembling a motor in a polymer network, also taking into account the effect of electrostatic changes in the motor heads. We explore important mechanical quantities and show that such a model is also capable of mechanosensing. Finally, we introduce a novel efficiency based on excess heat production by the chemical cycle which is directly related to the active tension the motor exerts. The chemical efficiencies differ considerably for motors with a different number of heads, while their mechanical properties remain qualitatively similar. For motors with a small number of heads, the chemical efficiency is maximal when they are frustrated, a trait that is not found in larger motors.

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Pieter Baerts, Christian Maes, Jiří Pešek, Herman Ramon. 2017-08-24. Tension and chemical efficiency of Myosin-II motors. https://arxiv.org/abs/1708.07454

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