Some of the fundamental building blocks of life, known as nitriles, have been identified by scientists at the heart of our Milky Way galaxy.
They were detected in a molecular cloud of gas and dust by an international team of researchers using two telescopes. Spain.
Nitriles are important building blocks for RNA, a DNA-like nucleic acid found in all living cells.
Experts said their discovery suggests that nitriles are one of the most abundant chemical families in the universe and lends support to the ‘RNA World’ theory of the origin of life.
This suggests that life on Earth originally relied solely on RNA, and DNA and protein enzymes evolved later.
RNA can perform both functions: storing and transcribing information, such as DNA, and catalyzing reactions, such as enzymes.
According to the ‘RNA World’ theory, nitriles and other building blocks for life need not all have originated on Earth itself.
Discovery: Some of the fundamental building blocks of life, known as nitrile, have been identified by scientists at the heart of our Milky Way galaxy. They were detected in a molecular cloud of gas and dust (similar to the one pictured) by an international team of researchers.
Experts said their discovery suggests that nitriles are one of the most abundant chemical families in the universe and lends support to the ‘RNA World’ theory of the origin of life. This suggests that nitriles may have originated in space and “hitchhiked” to young Earth in meteorites and comets (stock image)
They may also have arisen in space and ‘hitchhiked’ to young Earth amidst meteorites and comets during the ‘Late Heavy Bombardment’ 4.1 to 3.8 billion years ago.
As support, nitriles and other precursor molecules for nucleotides, lipids, and amino acids have been found in recent comets and meteorites.
The question is, where could these molecules have come from in space?
Prime candidates are molecular clouds, which are dense and cold regions of the interstellar medium suitable for the formation of complex molecules.
For example, molecular cloud G+0.693-0.027 has a temperature of about 100 K, is about three light-years across, and has a mass of about a thousand times our Sun.
There is currently no evidence of stars forming inside G+0.693-0.027, but scientists suspect it may become a stellar nursery in the future.
The team of experts identified a number of nitriles, including cyanoallene, propargyl cyanide, cyanopropin, and possibly cyanoformaldehyde and glycolnitrile; none of these had been in the cloud before and were known as G+0.693-0.027.
Lead study author Dr Víctor M. Rivilla, a researcher at Spain’s National Research Council’s Center for Astrobiology, said: “We show here that the chemistry that takes place in the interstellar medium can efficiently form the multiple nitriles that are so important. Molecular precursors of the “RNA World” scenario.
The chemical content of G+0.693-0.027 is similar to that of other star forming regions in our galaxy, as well as solar system objects such as comets.
‘This means that his work could give us important insights into the chemicals found in the nebula that gave rise to our planetary system.’
Researchers used the 100ft (30m) wide IRAM telescope Granada and the 130ft (40m) Yebes telescope in Guadalajara.
The team of experts detected a number of nitriles, including cyanoallene, propargyl cyanide and cyanopropylene, although they were not yet found in G+0.693-0.027 but were reported in the TMC-1 dark cloud in the constellation Taurus in 2019. and Auriga, a molecular cloud with conditions very different from G+0.693-0.027.
The scientists also found possible evidence of cyanoformaldehyde and glycolonitrile.
Cyanoformaldehyde was first detected in the molecular clouds of TMC-1 and Sgr B2 in the constellation Sagittarius and glycolonitrile in the Sun-like protostar IRAS16293-2422 B in the constellation Ophiuchus.
Two types of chemical building blocks – or nucleobases – are required for DNA and RNA to form.
Co-study author Dr Miguel A Requena-Torres, a lecturer at Towson University in Maryland, said: ‘Thanks to our observations over the last few years, including current results, we now know that nitriles are one of the most abundant chemical families in the world. Universe.
“We found them in molecular clouds at the center of our galaxy, protostars of different masses, meteorites and comets, as well as in the atmosphere of Saturn’s largest moon, Titan.”
Author Dr Izaskun Jiménez-Serra, also a researcher at the Spanish National Research Council Center for Astrobiology, said: “So far we have identified several simple precursors of ribonucleotides, which are the building blocks of RNA.
But there are still important missing molecules that are difficult to detect.
For example, we know that the origin of life on Earth probably also required other molecules, such as lipids, that were responsible for the formation of the first cells.
“Therefore, we should also focus on understanding how lipids can form from simpler precursors found in the interstellar medium.”
The study was published in the journal limits.
