Theoretical origin of life; criticism of the hype from Tour (Introduction)

by David Turell @, Sunday, July 14, 2019, 19:29 (1747 days ago) @ David Turell

James Tour has produced a long critical article against the hype of OOL research, and finds the research itself quite lacking. Very long essay:

https://inference-review.com/article/time-out

"This essay comprises an argument, but it also contains an appeal to the OOL community. The history of science suggests that on occasion what is required for research to flourish is not further research—at least to the extent that further research involves doing the same thing. This is one of those times.

***

"Constructing the molecules necessary for life from their prebiotic precursors represents one goal of OOL research; putting them together, another. Some of synthetic chemistry is pedestrian, and some ingenious. Fundamental questions remain unaddressed. Claims that these structures could be prepared under prebiotic conditions in high enantiomeric purity using inorganic templates, or any presumed templates, have never been realized. The carbohydrates, amino acids, lipids, and other compounds within each of these classes require specific methods in order to control their regiochemistry and stereochemistry. The differences in reaction rates often require chiral systems acting upon chiral molecules. If this were possible under prebiotic conditions, it is odd that it cannot be replicated by synthetic chemists.

"They have, after all, had 67 years to try.

***

"A Harvard researcher seeking a model for the earliest cells has created a system that self-assembles from a chemical soup into cell-like structures that grow, move in response to light, replicate, and exhibit signs of rudimentary evolutionary selection [emphasis added].5
This degree of hyperbole is excessive.6 Nothing in this experiment had growing cell-like structures with replication, or that exhibited aspects of evolutionary selection.

***

"Terminology is one thing, non-sequiturs quite another. “After much trial and error,” the authors write, “one protocell assembles the complicated molecular machinery that enables it to divide into daughter cells. This paves the way for the first living microbial community.” How is the molecular machinery made? They do not say. The mechanisms needed for cellular division are complex, requiring cascades of precisely functioning enzymes. There is nothing between what the authors demonstrate and what they claim to have established, and nothing they propose “paves the way for the first living microbial community.”

***

"Peter Tompa and George Rose have calculated that if one considers only protein combinations in a single yeast cell, the result would be an estimated 1079,000,000,000 combinations.14 The authors understand that this is a very large number, one that precludes “formation of a functional interactome by trial and error complex formation within any meaningful span of time.”

***

"I have discussed these issues with OOL researchers, and I am amazed that they fail to appreciate the magnitude of the problem in building molecules. They see little difficulty in accepting a chemical synthesis where a desired product is mixed with a large array of closely related yet undesired compounds. They seem unaware that separations would be enormously complex, and subsequent reactions unavailing. In a 2018 article for Progress in Biophysics and Molecular Biology, Edward Steele et al. concede the following.

"The transformation of an ensemble of appropriately chosen biological monomers (e.g. amino acids, nucleotides) into a primitive living cell capable of further evolution appears to require overcoming an information hurdle of superastronomical proportions, an event that could not have happened within the time frame of the Earth except, we believe, as a miracle. All laboratory experiments attempting to simulate such an event have so far led to dismal failure. (my bold)

***

"It is time for a temporary time out. Why not admit what we cannot yet explain: the mass transfer of starting materials to the molecules needed for life; the origin of life’s code; the combinatorial complexities present in any living system; and the precise non-regular assembly of cellular components?

"It would be helpful if leading researchers, among them very sophisticated synthetic chemists, were to step back, pause, and join forces. If the origins of life remain a mystery, two goals are within reach: an agreement about the rational standards by which OOL research should be judged, and a candid acknowledgment of the problems that remain to be overcome. A statement of this sort would be reassuring in its candor."

Comment: A superb commentary supporting my presentations of the super-hype re OOL. Note my bold. Life is a miracle event.


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