That is, if RNA world is correct. From ScienceDaily:
Researchers at UC Santa Barbara have now found evidence that the amino acid arginine (or its prebiotic world equivalent) may have been a more important ingredient in this soup than previously thought.
“People tend to think of arginine as not being prebiotic,” said Irene Chen, a biophysicist whose research focuses on the chemical origins of life. “They tend to think of the simpler amino acids as being plausible, such as glycine and alanine.” Arginine, by contrast, is relatively more complex, and was therefore thought to have entered the game at a later stage.
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The researchers are careful to point out that although the amino acid we call arginine was found to be important in the aptamer-protein binding interactions they examined, billions of years ago the biomolecule may not necessarily have been today’s arginine but perhaps a positively charged primordial equivalent.
This development sheds more light on what might have been the ideal conditions for the rise of life. There are a variety of hypotheses — from comets to hydrothermal vents to other environments — that may have been favorable for the eventual evolution of cells, as well as several landmark experiments that bolster the RNA World idea.
“If we had found that glycine was really important for RNA-protein interactions — and glycine is everywhere — then that would not have been helpful for determining plausible conditions,” said Chen. “But finding that arginine was important constrains the type of scenarios that could have given rise to the genetic code.” Paper. (public access) – Celia Blanco, Marco Bayas, Fu Yan, Irene A. Chen. Analysis of Evolutionarily Independent Protein-RNA Complexes Yields a Criterion to Evaluate the Relevance of Prebiotic Scenarios. Current Biology, 2018; DOI: 10.1016/j.cub.2018.01.014 More.
Another piece in the puzzle? Or not? RNA world is itself under fire.
One thing about the origin of life industry: Its fuel is speculation and that, happily, never runs out.
See also: Welcome to “RNA world,” the five-star hotel of origin-of-life theories
Researchers: RNA world can’t produce genetic code