Intermediate stages in the origin of metabolism

[Dan_Eastwood]

Something to stir the OoL pot.

Intermediate stages in the origin of metabolism at a phosphorylating hydrothermal vent

Natalia Mrnjavac et al.

Intermediate stages in the origin of metabolism at a phosphorylating hydrothermal vent.Sci. Adv.12,eaef3128(2026).DOI:10.1126/sciadv.aef3128

Abstract

The origin of life required the emergence of metabolism, an autocatalytic network of enzymatic reactions that synthesize amino acids, nucleotides, and cofactors. At the origin of metabolism, there were no enzymes—how did it start? Empirical studies addressing early metabolic evolution are lacking. Harnessing protein structures for metabolic enzymes, we identify intermediate states in primordial metabolic assembly. We show that enzymatic metabolism in the universal common ancestor was incomplete, undergoing final assembly independently in the lineages leading to bacteria and archaea. Native transition metals—iron, cobalt, nickel, and palladium—served as the catalytic forerunners of both enzymes and cofactors at metabolic origin, while phosphite supplied energy, as it phosphorylates adenosine 5′-monophosphate to adenosine 5′-diphosphate and serine to phosphoserine using native metal catalysts in water. Phosphite and native metals occur in serpentinizing hydrothermal systems, identifying an energy-supplying, catalytic site of metabolic origin. Cofactors liberated nascent metabolism from native metal catalysts, engendering its autocatalytic state.

https://www.science.org/doi/10.1126/sciadv.aef3128

The fluffy version from SciAm:

Life on Earth may have emerged not once but twice

[Argon]

I believe Larry Moran at Sandwalk also discussed this work: Sandwalk: The evolution of metabolic enzymes in LUCA, Bacteria, and Archaea

[Dan_Eastwood]

You beat me to it

[Dan_Eastwood]

A better summary, h/t @sfmatheson

https://www.smithsonianmag.com/science-nature/a-new-study-points-to-two-origins-of-life-on-earth-by-tracing-early-chemical-reactions-in-single-celled-organisms-180989260/

[John_Harshman]

Note that the paper itself makes no such claim. It all depends on a matter of definition, whether you consider that the LUCA was alive. Apparently, to SciAm (and the Smithsonian), an organism that relies on metals unattached to proteins for some of its enzymes isn’t alive. The authors of the paper don’t say that and imply otherwise.