论文标题
边缘效应主导着有限分子低聚物的热力学复制
Edge-effects dominate copying thermodynamics for finite-length molecular oligomers
论文作者
论文摘要
生活系统通过将单体单元组装成有限的寡聚（短聚合物）副本，从而生成携带信息分子（例如DNA）的副本。我们探讨了复制过程在复制热力学中的启动和终止的作用。通过将副本形成的自由化变化分为信息和化学术语，我们表明副本精度在整体热力学中没有任何直接作用。取而代之的是，与通过随机采样单体获得的序列相比，产生与环境中的低聚物更相似的输出是热力学成本高昂的。根据周围环境，复制精度可以是热力学中性的，甚至可以偏爱。因此，低聚物复制机制可以用作互连化学和基于信息的自由能的信息引擎。无限长度聚合物得出的精度的硬热力学约束代替了副本与模板连接时所经历的动力学障碍。这些障碍很容易被短的低聚物所覆盖。
Living systems produce copies of information-carrying molecules such as DNA by assembling monomer units into finite-length oligomer (short polymer) copies. We explore the role of initiation and termination of the copy process in the thermodynamics of copying. By splitting the free-energy change of copy formation into informational and chemical terms, we show that copy accuracy plays no direct role in the overall thermodynamics. Instead, it is thermodynamically costly to produce outputs that are more similar to the oligomers in the environment than sequences obtained by randomly sampling monomers. Copy accuracy can be thermodynamically neutral, or even favoured, depending on the surroundings. Oligomer copying mechanisms can thus function as information engines that interconvert chemical and information-based free energy. Hard thermodynamic constraints on accuracy derived for infinite-length polymers instead manifest as kinetic barriers experienced while the copy is template-attached. These barriers are easily surmounted by shorter oligomers.
