Exactly how life came from inanimate objects remains a big mystery, and new research suggests that natural selection may have played a role before life itself existed on Earth. It became clear. By recreating a primitive soup, scientists have identified how a cocktail of specific amino acids carries the genetic code of all life forms on Earth.
Although there are hundreds of different amino acids in nature, a core set of 20 are found in all living things. Escherichia coli to the elephant. That’s because we can trace everything back through the complex phylogenetic tree of life to a single common ancestor that existed billions of years ago. But what’s so special about these 20 specific amino acids? Finding out was the goal of a new study jointly led by scientists at Johns Hopkins University and Charles University.
The team recreated conditions on the early Earth in the laboratory, including a mixture of amino acids that were very common before life appeared. It is thought to have been produced when it interacted with gas, but others arrived aboard meteorites that hit Earth more frequently than it does today.
In their experiments, the team observed that even in the absence of life, a sort of natural selection process takes place. Ancient organic compounds tended to integrate into their biochemistry those amino acids most suited to folding proteins into key forms for their important functions, making these compounds more likely to survive. Over time, the number of organic compounds with properties favorable to life simply increased.
“Protein folding basically enabled evolution before life existed on Earth,” said Stephen Fried, co-lead author of the study. We were able to evolve long ago, and even before DNA existed, we were able to make natural selections for useful chemicals for life.”
The team says this process could help explain the mysterious transition between inanimate and living things. It was able to evolve into everything else while preserving those “special” amino acids.
“This sophisticated method of converting genetic molecules such as DNA and RNA into proteins is necessary for evolution in the Darwinian sense,” Fried said. “But DNA replication also requires proteins, so it’s a chicken-and-egg question. indicates that you may have selected
This research has more than just implications for life on Earth. Similar rules may apply to other worlds. After all, the amino acid has been detected on comets and asteroids, and seems to be fairly common there.
“The universe seems to love amino acids,” Freed said. “Maybe if life was found on another planet, it wouldn’t be much different.”
This research Journal of the American Chemical Society.
Source: Johns Hopkins University
