Peptides consist of specific amino acids set up in a particular order. Amino acids, nucleobases, and various sugars found in meteoroids, for example, show that this origin might be extraterrestrial in nature. For a peptide to be formed from specific amino acid molecules, extremely unique conditions are required that were formerly assumed to be more likely to exist on Earth.
In this process, individual amino acids combine to form a chain. “Our quantum chemical computations have now shown that the amino acid glycine can be formed through a chemical precursor– called an amino ketene– integrating with a water molecule.
Dr. Serge Krasnokutski studies the formation of biomolecules at low temperature level in a vacuum. Credit: Jens Meyer/University of Jena
Research group from Friedrich Schiller University Jena and limit Planck Institute for Astronomy discovers idea to possible extraterrestrial origin of peptides.
Scientists from the Friedrich Schiller University Jena and the Max Planck Institute for Astronomy have found a brand-new idea in the search for the origin of life by revealing that peptides can form on dust under conditions such as those dominating in deep space. These particles, which are among the basic structure blocks of all life, may for that reason not have actually stemmed on our world at all, but potentially in cosmic molecular clouds.
Chains of amino acids
All life as we know it consists of the same chemical foundation. These consist of peptides, which perform numerous entirely various functions in the body– transferring substances, accelerating reactions, or forming supporting scaffolds in cells. Peptides include individual amino acids organized in a particular order. The exact order figures out a peptides ultimate properties.
How these flexible biomolecules came into being is one of the concerns about the origin of life. Amino acids, nucleobases, and various sugars discovered in meteoroids, for example, show that this origin might be extraterrestrial in nature. However, for a peptide to be formed from specific amino acid molecules, very unique conditions are needed that were previously presumed to be more likely to exist on Earth.
The initial step requires water, while for the 2nd step, there need to be no water
In this process, private amino acids combine to form a chain. “Our quantum chemical estimations have now revealed that the amino acid glycine can be formed through a chemical precursor– called an amino ketene– combining with a water molecule.
With this understanding, the group led by the physicist Krasnokutski has actually now been able to show a response path that can occur under cosmic conditions and does not need water.
” Instead of taking the chemical detour in which amino acids are formed, we wanted to discover out whether amino ketene molecules could not be formed rather and integrate straight to form peptides,” states Krasnokutski, explaining the standard concept behind the work. He includes: “And we did this under the conditions that prevail in cosmic molecular clouds, that is to state on dust particles in a vacuum, where the corresponding chemicals are present in abundance: carbon, ammonia, and carbon monoxide.”
In an ultra-high vacuum chamber, substrates that work as a design for the surface area of dust particles were combined with carbon, carbon, and ammonia monoxide at about one quadrillionth of normal atmospheric pressure and minus 263 degrees Celsius.
” Investigations revealed that under these conditions, the peptide polyglycine was formed from the basic chemicals,” Krasnokutski states. “These are therefore chains of the extremely basic amino acid glycine, and we observed different lengths. The longest specimens consisted of eleven units of the amino acid.”
In this experiment, the German group was likewise able to identify the thought amino ketene. “The truth that the response can take place at such low temperatures at all is due to the amino ketene molecules being incredibly reactive.
Quantum mechanical tunneling effect may play a function
” It was however unexpected to us that the polymerization of amino ketene might happen so easily under such conditions,” says Krasnokutski. In this unique reaction action, a hydrogen atom changes its place.
Now that it is clear that not only amino acids, however also peptide chains, can be developed under cosmic conditions, we may have to look not only to Earth however likewise more into area when investigating the origin of life.
Recommendation: “A pathway to peptides in area through the condensation of atomic carbon” by S. A. Krasnokutski, K.-J. Chuang, C. Jäger, N. Ueberschaar and Th. Henning, 10 February 2022, Nature Astronomy.DOI: 10.1038/ s41550-021-01577-9.