Facultad de Ciencias, Universidad Nacional Autónoma de México, Apdo. Postal 70-407, Cd. Universitaria, 04510 México DF, Mexico.
Cold Spring Harb Perspect Biol. 2010 Nov;2(11):a002089. doi: 10.1101/cshperspect.a002089. Epub 2010 Jun 9.
Following the publication of the Origin of Species in 1859, many naturalists adopted the idea that living organisms were the historical outcome of gradual transformation of lifeless matter. These views soon merged with the developments of biochemistry and cell biology and led to proposals in which the origin of protoplasm was equated with the origin of life. The heterotrophic origin of life proposed by Oparin and Haldane in the 1920s was part of this tradition, which Oparin enriched by transforming the discussion of the emergence of the first cells into a workable multidisciplinary research program. On the other hand, the scientific trend toward understanding biological phenomena at the molecular level led authors like Troland, Muller, and others to propose that single molecules or viruses represented primordial living systems. The contrast between these opposing views on the origin of life represents not only contrasting views of the nature of life itself, but also major ideological discussions that reached a surprising intensity in the years following Stanley Miller's seminal result which showed the ease with which organic compounds of biochemical significance could be synthesized under putative primitive conditions. In fact, during the years following the Miller experiment, attempts to understand the origin of life were strongly influenced by research on DNA replication and protein biosynthesis, and, in socio-political terms, by the atmosphere created by Cold War tensions. The catalytic versatility of RNA molecules clearly merits a critical reappraisal of Muller's viewpoint. However, the discovery of ribozymes does not imply that autocatalytic nucleic acid molecules ready to be used as primordial genes were floating in the primitive oceans, or that the RNA world emerged completely assembled from simple precursors present in the prebiotic soup. The evidence supporting the presence of a wide range of organic molecules on the primitive Earth, including membrane-forming compounds, suggests that the evolution of membrane-bounded molecular systems preceded cellular life on our planet, and that life is the evolutionary outcome of a process, not of a single, fortuitous event.
1859 年《物种起源》出版后，许多自然学家接受了这样一种观点，即生物是无生命物质逐渐转化的历史产物。这些观点很快与生物化学和细胞生物学的发展融合在一起，并导致了这样的提议，即原生质的起源等同于生命的起源。奥巴林和霍尔丹在 20 世纪 20 年代提出的异养生命起源就是这一传统的一部分，奥巴林通过将第一个细胞的出现的讨论转变为一个可行的多学科研究计划，丰富了这一传统。另一方面，科学趋势是在分子水平上理解生物现象，这导致了像特罗兰、穆勒等人提出的观点，即单个分子或病毒代表原始的生命系统。这两种对立的生命起源观点之间的对比不仅代表了对生命本身本质的不同看法，而且还代表了在斯坦利·米勒的开创性结果之后的几年中达到惊人强度的主要思想讨论，该结果表明在假定的原始条件下，生物化学意义上的有机化合物很容易合成。事实上，在米勒实验之后的几年里，对生命起源的理解受到了 DNA 复制和蛋白质生物合成研究的强烈影响，从社会政治角度来看，受到冷战紧张局势造成的氛围的影响。RNA 分子的催化多功能性显然值得对穆勒的观点进行批判性重新评估。然而，核酶的发现并不意味着能够自我催化的核酸分子准备好作为原始基因在原始海洋中漂浮，或者 RNA 世界完全由前生物汤中存在的简单前体组装而成。支持原始地球上存在广泛的有机分子的证据，包括形成膜的化合物，表明膜结合分子系统的进化先于我们星球上的细胞生命，并且生命是一个过程的进化结果，而不是单一的、偶然的事件。
