Rempel Mark, Emberly Eldon
Department of Physics, Simon Fraser University, 8888 University Dr, Burnaby, BC V5A 1S6, Canada.
Micromachines (Basel). 2022 Jun 9;13(6):914. doi: 10.3390/mi13060914.
Molecular motors play a vital role in the transport of material within the cell. A family of motors of growing interest are burnt bridge ratchets (BBRs). BBRs rectify spatial fluctuations into directed motion by creating and destroying motor-substrate bonds. It has been shown that the motility of a BBR can be optimized as a function of the system parameters. However, the amount of energy input required to generate such motion and the resulting efficiency has been less well characterized. Here, using a deterministic model, we calculate the efficiency of a particular type of BBR, namely a polyvalent hub interacting with a surface of substrate. We find that there is an optimal burn rate and substrate concentration that leads to optimal efficiency. Additionally, the substrate turnover rate has important implications on motor efficiency. We also consider the effects of force-dependent unbinding on the efficiency and find that under certain conditions the motor works more efficiently when bond breaking is included. Our results provide guidance for how to optimize the efficiency of BBRs.
分子马达在细胞内物质运输中起着至关重要的作用。一类越来越受关注的马达是烧桥棘轮（BBRs）。BBRs通过创建和破坏马达 - 底物键将空间波动整流为定向运动。已经表明，BBR的运动性可以作为系统参数的函数进行优化。然而，产生这种运动所需的能量输入量以及由此产生的效率尚未得到很好的表征。在这里，我们使用确定性模型计算一种特定类型的BBR的效率，即与底物表面相互作用的多价枢纽。我们发现存在导致最佳效率的最佳燃烧速率和底物浓度。此外，底物周转率对马达效率有重要影响。我们还考虑了力依赖的解离对效率的影响，发现在某些条件下，当包括键断裂时，马达工作效率更高。我们的结果为如何优化BBR的效率提供了指导。
