One of the great scientific questions concerns the origin of life. Intimately wrapped into this question is how the discrete functional components (e.g. energy production, DNA synthesis, protein synthesis, etc.) were assembled into a functional cell. A recent (peer reviewed) paper by William Martin and his group (1), described in New Scientist, under the headline of “Universal ancestor of all life on Earth was only half alive” (2), inches us closer to an understanding of the process.

The authors searched extant microorganisms for the most ancient genes, those most likely to have been in LUCA, the Last Universal Common Ancestor of all life. They found 355 candidate genes. To quote the New Scientist article:

“One characteristic of almost all living cells is that they pump ions across a membrane to generate an electrochemical gradient, then use that gradient to make the energy-rich molecule ATP. The team’s results suggest LUCA could not generate such a gradient, but could harness an existing one.

That fits in with the idea that the first life got its energy from the natural gradient between (hydrothermal) vent water and seawater, and so was bound to these vents. Only later did the ability to generate gradients evolve, allowing life to break away from the vents.”

If the findings of this study hold up, it would be proof of principle that different physical systems could have provided functional equivalence for what we currently consider to be discrete, integral biological components of the cell.

They also imply that cells were assembled over a period of time from discrete functional chemical units, starting with "not alive" and ending in "alive" but with no clearly defined bright line separating one state from another.

These findings would thus close another of the "gaps" in our knowledge that god can inhabit and drive an additional large nail into the coffin of "irreducible complexity."

1. Nature Microbiology, doi.org/bm2s).
2. https://www.newscientist.com/article/mg23130844-300-universal-ancestor-o...