Abstract:
The path from life\'s origin to the emergence of the eukaryotic cell was long and complex, and as such it is rarely treated in one publication. Here, we offer a sketch of this path, recognizing that there are points of disagreement and that many transitions are still shrouded in mystery. We assume life developed within microchambers of an alkaline hydrothermal vent system. Initial simple reactions were built into more sophisticated reflexively autocatalytic food-generated networks (RAFs), laying the foundation for life\'s anastomosing metabolism, and eventually for the origin of RNA, which functioned as a genetic repository and as a catalyst (ribozymes). Eventually, protein synthesis developed, leading to life\'s biology becoming dominated by enzymes and not ribozymes. Subsequent enzymatic innovation included ATP synthase, which generates ATP, fueled by the proton gradient between the alkaline vent flux and the acidic sea. This gradient was later internalized via the evolution of the electron transport chain, a preadaptation for the subsequent emergence of the vent creatures from their microchamber cradles. Differences between bacteria and archaea suggests cellularization evolved at least twice. Later, the bacterial development of oxidative phosphorylation and the archaeal development of proteins to stabilize its DNA laid the foundation for the merger that led to the formation of eukaryotic cells.
摘要:
从生命起源到真核细胞出现的路径是漫长而复杂的,因此,它很少在一份出版物中得到处理。这里,我们提供了这条路径的草图,认识到存在分歧,许多过渡仍然笼罩在神秘之中。我们假设生命是在碱性热液通气系统的微室中发展起来的。最初的简单反应被构建到更复杂的反射自催化食品生成网络(RAF)中,为生命的吻合代谢奠定基础,最终是RNA的起源,它作为遗传储存库和催化剂(核酶)。最终,蛋白质合成发达,导致生命的生物学变得由酶而不是核酶主导。随后的酶促创新包括ATP合酶,产生ATP,由碱性通气通量和酸性海之间的质子梯度推动。这种梯度后来通过电子传输链的演化被内化,对随后从其微室摇篮中出现的通风口生物的预适应。细菌和古细菌之间的差异表明细胞化至少进化了两次。稍后,氧化磷酸化的细菌发育和稳定其DNA的蛋白质的古细菌发育为导致真核细胞形成的合并奠定了基础。