Theoretical origin of life; more on hydrothermal vents (Introduction)

by David Turell , Friday, March 13, 2020, 17:22 (1716 days ago) @ David Turell

A new study pushing the theory of hydrothermal vents:

https://www.sciencedaily.com/releases/2020/03/200312101054.htm

"Since the origin of life, metabolic networks provide cells with nutrition and energy. Modern networks require thousands of enzymes that perform catalysis. Such networks must have arisen from simpler precursors. Investigating the metabolism of modern cells, Xavier et al. have identified ancient and conserved autocatalytic networks at the core of microbial metabolism that require only co-factors and metals as catalysts. (my bold)

***

"Living cells are the end product of metabolic networks. Food molecules that enter the cell are converted to central intermediates that are then channeled into the pathways that produce the molecules of which cells are made. These networks typically entail more than 1000 reactions, almost all of which are performed by enzymes (proteins), which are encoded by genes (nucleic acids). The link between genes and proteins is, in turn, the universal genetic code that instructs ribosomes to make proteins according to the information stored in genes. (my bold)

***

"The existence and properties of such autocatalytic sets remained the subject of much speculation and decades of fierce debate until the mathematician Mike Steel from the University of Canterbury in New Zealand and Wim Hordijk, a computer scientist from The Netherlands, both coauthors on the study, found ways of harnessing them in the computer. They found that a particular class of autocatalytic sets called RAFs (for reflexively autocatalytic food generated networks), which are very similar in design to cellular metabolism, have the unexpected property of being downright likely to arise from scratch. "The surprise is that the elements only need to add a tiny amount of catalysis to the system before they start to make more of themselves" says Steel. "This is what physicists call self organization, a kind of holy grail in origin of life research" adds Hordijk.

***

"The two kinds of unicellular organisms at the focus of the study, called acetogens and methanogens, have long been in the sights of microbiologists interested in the origin of life. They have been linked to the last universal common ancestor, LUCA, and to geochemical reactions at hydrothermal vents.

***

"Did life arise at hydrothermal vents? "The closer we look, the more signs keep pointing in that direction" says Xavier, "the idea keeps uncovering findings that converge. These vents were probably the first bioreactors on Earth." The identification of autocatalytic networks as components of modern metabolism takes them off the drawing board and into the real world of microbial life. That they uncover fossils from the earliest stages of chemical evolution was unexpected, and opens up new routes for the study of our deepest evolutionary past, probing the time 4 billion years ago, when life was just starting from a small set of naturally-occurring chemical reactions that took place somewhere, perhaps at a hydrothermal vent."

Comment: Once again a highly theoretical view of how life might have automatically started, ignoring the statement in the study about how complex the actual metabolism any living organisms happens to be. Note the first bold. The second bold notes the primary role of onboard information. Where did the information come from if al of this appeared automatically? Information requires mental activity to create it.