Tian Tian, Chu Xin-Yi, Yang Yi, Zhang Xuan, Liu Ye-Mao, Gao Jun, Ma Bin-Guang, Zhang Hong-Yu
Hubei Key Laboratory of Agricultural Bioinformatics, College of Informatics, Huazhong Agricultural University, Wuhan 430070, China.
Beijing National Center for Molecular Sciences, Institute of Theoretical and Computational Chemistry, College of Chemistry and Molecular Engineering, Peking University, Beijing 100871, China.
Life (Basel). 2019 May 22;9(2):43. doi: 10.3390/life9020043.
Phosphates are essential for modern metabolisms. A recent study reported a phosphate-free metabolic network and suggested that thioesters, rather than phosphates, could alleviate thermodynamic bottlenecks of network expansion. As a result, it was considered that a phosphorus-independent metabolism could exist before the phosphate-based genetic coding system. To explore the origin of phosphorus-dependent metabolism, the present study constructs a protometabolic network that contains phosphates prebiotically available using computational systems biology approaches. It is found that some primitive phosphorylated intermediates could greatly alleviate thermodynamic bottlenecks of network expansion. Moreover, the phosphorus-dependent metabolic network exhibits several ancient features. Taken together, it is concluded that phosphates played a role as important as that of thioesters during the origin and evolution of metabolism. Both phosphorus and sulfur are speculated to be critical to the origin of life.
磷酸盐对现代新陈代谢至关重要。最近一项研究报道了一个无磷酸盐的代谢网络，并表明硫酯而非磷酸盐可以缓解网络扩展的热力学瓶颈。因此，有人认为在基于磷酸盐的遗传编码系统之前可能存在不依赖磷的新陈代谢。为了探索依赖磷的新陈代谢的起源，本研究使用计算系统生物学方法构建了一个包含益生元可用磷酸盐的原始代谢网络。研究发现，一些原始的磷酸化中间体可以极大地缓解网络扩展的热力学瓶颈。此外，依赖磷的代谢网络表现出几个古老的特征。综上所述，得出结论：在新陈代谢的起源和进化过程中，磷酸盐发挥了与硫酯同样重要的作用。据推测，磷和硫对生命起源都至关重要。
