| IN BRIEF |
|
NASA, in collaboration with UCLA, has just made a discovery that could revolutionize our understanding of the origins of life on Earth and elsewhere. This new scientific paradigm challenges the idea that the building blocks of life are subject to strict rules of molecular chirality.
Could your first name really transform your face? Disturbing study reveals
A discovery that challenges established theories
Researchers from NASA and UCLA have discovered that the first RNA molecules on Earth may have been more flexible than previously thought. Contrary to the belief that these molecules adhered only to a “left-handed” structure, they may have been able to catalyze amino acids in two different hands.
This flexibility calls into question the notion of homochiralitéaccording to which life follows a uniformly oriented molecular pattern. Such an upheaval could mean that the initial conditions of life were less rigid, opening the way to new possibilities for chemical evolution.
Chirality: a fundamental concept
Chirality, or the “hand” of molecules, plays a crucial role in biology. Molecules can exist in two mirror forms, like human hands, impossible to superimpose. It is a fundamental principle that governs the structure of amino acids and sugars in living organisms.
NASA creates clouds with a chemical compound over Norway: find out what is behind this worrying initiative
Until now, scientists believed that this preference for left or right shapes was essential for the emergence of life. However, the new study suggests that this rule may not have been so fixed originally.
Implications for the origins of life
The flexibility of early RNA molecules could mean that life on Earth was not predetermined by strict chiral preference. This discovery opens the possibility that the first forms of life evolved from varied molecular structures.
Surprise ! The best city to live in the world is in France, and you’ll never guess why…
The researchers, led by Irene Chen, demonstrated that ribozymes, a type of RNA molecule, could produce amino acids of two types depending on the experimental conditions. This unexpected result challenges the traditional model of chemical evolution towards DNA and proteins.
Consequences for astrobiology
This discovery has significant implications for astrobiology, the study of life beyond Earth. If molecules on Earth were more flexible, life elsewhere in the universe might follow different chemical paths.
NASA missions, like OSIRIS-REx, that bring back samples from asteroids could provide clues to the chemical diversity of life’s building blocks. Chemical flexibility may be a common feature of extraterrestrial life.
Chirality Difference Table
| Element | Chiral on Earth | Potential flexibility |
|---|---|---|
| Amino acids | Gaucher | Left and right |
| sucres | Right-handed | Left and right |
A new perspective on evolution
This new model suggests that the evolution of molecules could have been influenced by environmental pressures rather than fixed chemical rules. Alberto Vázquez-Salazar, co-author of the study, emphasizes that this discovery calls into question chemical determinism.
By viewing evolution through the lens of flexibility and adaptability, we may discover life forms that do not follow Earth’s standards. This prompts a rethinking of theories about the origins of life.
As we continue to explore the universe, could we one day find a totally different form of life, dictated by other molecular rules ? This research opens a new era in the study of life, both on our planet and beyond.
Source : Dailygalaxy
