It is often thought that the structural complexity of living organisms places Life outside the laws of Physics. According to the Second Law of Thermodynamics, inanimate matter tends towards ever-increasing randomness. Most thermodynamic studies on the living system are course-grained in the sense that it is the whole organism which is considered and they lack microscopic details. In these studies, as the living system is an open system, non-linear thermodynamics have been used. This requires that a number of assumptions be made concerning the living system itself, which may not be correct in organisms living under natural environmental conditions. In the present study, we depart from this approach and use a fine-grained analysis of the genesis of subcellular protein complex structures. The analysis is performed in terms of classical equilibrium thermodynamics using the acquired knowledge of protein/protein interactions. In this way, it is demonstrated that the spontaneous creation of ordered subcellular structures occurs in accordance with the Second Law of Thermodynamics. We specifically consider the simple example of protein dimer and trimer formation from its monomer components, both in vitro and with chaperone assistance in vivo. The entropy decrease associated with protein complex assembly, on which the continuing debate is founded, is shown to be a relatively small component in the overall and positive entropy increase.

Graphic abstract

中文翻译：

---

平衡热力学和细胞中蛋白质-蛋白质复合物的起源

人们通常认为，生物体的结构复杂性将生命置于物理定律之外。根据热力学第二定律，无生命的物质趋向于不断增加的随机性。大多数关于生命系统的热力学研究都是粗粒度的，因为它是被考虑的整个有机体，并且它们缺乏微观细节。在这些研究中，由于生命系统是一个开放系统，因此使用了非线性热力学。这需要对生命系统本身做出一些假设，这对于生活在自然环境条件下的生物体来说可能是不正确的。在本研究中，我们脱离了这种方法，对亚细胞蛋白质复合结构的起源进行了细粒度分析。使用获得的蛋白质/蛋白质相互作用知识，根据经典平衡热力学进行分析。通过这种方式，证明了有序亚细胞结构的自发产生是根据热力学第二定律发生的。我们特别考虑了从其单体成分形成蛋白质二聚体和三聚体的简单例子，无论是在体外还是在体内分子伴侣的帮助下。与蛋白质复合体组装相关的熵减少，持续争论的基础，被证明是整体和正熵增加的一个相对较小的组成部分。结果表明，有序亚细胞结构的自发产生是根据热力学第二定律发生的。我们特别考虑了从其单体成分形成蛋白质二聚体和三聚体的简单例子，无论是在体外还是在体内分子伴侣的帮助下。与蛋白质复合体组装相关的熵减少，持续争论的基础，被证明是整体和正熵增加的一个相对较小的组成部分。结果表明，有序亚细胞结构的自发产生是根据热力学第二定律发生的。我们特别考虑了从其单体成分形成蛋白质二聚体和三聚体的简单例子，无论是在体外还是在体内分子伴侣的帮助下。与蛋白质复合体组装相关的熵减少，持续争论的基础，被证明是整体和正熵增加的一个相对较小的组成部分。

图形摘要