Building blocks of life can form long before stars

November 16, 2020

An international team of scientists have shown that glycine, the simplest amino acid and an important building block of life, can form under the harsh conditions that govern chemistry in space.

The results, published in Nature Astronomy, suggest that glycine, and very likely other amino acids, form in dense interstellar clouds well before they transform into new stars and planets.

Comets are the most pristine material in our Solar System and reflect the molecular composition present at the time our Sun and planets were just about to form. The detection of glycine in the coma of comet 67P/Churyumov-Gerasimenko and in samples returned to Earth from the Stardust mission suggests that amino acids, such as glycine, form long before stars. However until recently, it was thought that glycine formation required energy, setting clear constraints to the environment in which it can be formed.

In the new study the international team of astrophysicists and astrochemical modelers, mostly based at the Laboratory for Astrophysics at Leiden Observatory, the Netherlands, have shown that it is possible for glycine to form on the surface of icy dust grains, in the absence of energy, through 'dark chemistry'. The findings contradict previous studies that have suggested UV radiation was required to produce this molecule.

Dr Sergio Ioppolo, from Queen Mary University of London and lead author of the article, said: "Dark chemistry refers to chemistry without the need of energetic radiation. In the laboratory we were able to simulate the conditions in dark interstellar clouds where cold dust particles are covered by thin layers of ice and subsequently processed by impacting atoms causing precursor species to fragment and reactive intermediates to recombine."

The scientists first showed methylamine, the precursor species of glycine that was detected in the coma of the comet 67P, could form. Then, using a unique ultra-high vacuum setup, equipped with a series of atomic beam lines and accurate diagnostic tools, they were able to confirm glycine could also be formed, and that the presence of water ice was essential in this process.

Further investigation using astrochemical models confirmed the experimental results and allowed the researchers to extrapolate data obtained on a typical laboratory timescale of just one day to interstellar conditions, bridging millions of years. "From this we find that low but substantial amounts of glycine can be formed in space with time," said Professor Herma Cuppen from Radboud University, Nijmegen, who was responsible for some of the modelling studies within the paper.

"The important conclusion from this work is that molecules that are considered building blocks of life already form at a stage that is well before the start of star and planet formation," said Harold Linnartz, Director of the Laboratory for Astrophysics at Leiden Observatory. "Such an early formation of glycine in the evolution of star-forming regions implies that this amino acid can be formed more ubiquitously in space and is preserved in the bulk of ice before inclusion in comets and planetesimals that make up the material from which ultimately planets are made."

"Once formed, glycine can also become a precursor to other complex organic molecules," concluded Dr Ioppolo. "Following the same mechanism, in principle, other functional groups can be added to the glycine backbone, resulting in the formation of other amino acids, such as alanine and serine in dark clouds in space. In the end, this enriched organic molecular inventory is included in celestial bodies, like comets, and delivered to young planets, as happened to our Earth and many other planets."
-end-
Notes to editors

* Research publication: 'A non-energetic mechanism for glycine formation in the interstellar medium' S. Ioppolo, G. Fedoseev, K.-J. Chuang, H.M. Cuppen, A.R. Clements, M. Jin, R.T. Garrod, D. Qasim, V. Kofman, E.F. van Dishoeck, and H. Linnartz; Nature Astronomy, DOI:10.1038/s41550-020-01249-0. * Once published online, the manuscript will be available at the following URL: https://www.nature.com/articles/s41550-020-01249-0

Contact information

Dr. Sergio Ioppolo
s.ioppolo@qmul.ac.uk
Mobile number: +44 7760588286

Prof. Harold Linnartz
linnartz@strw.leidenuniv.nl
Mobile number: 06-18878584

See also: http://www.laboratory-astrophysics.eu

Queen Mary University of London

Related Amino Acids Articles from Brightsurf:

Igniting the synthetic transport of amino acids in living cells
Researchers from ICIQ's Ballester group and IRBBarcelona's Palacín group have published a paper in Chem showing how a synthetic carrier calix[4]pyrrole cavitand can transport amino acids across liposome and cell membranes bringing future therapies a step closer.

Microwaves are useful to combine amino acids with hetero-steroids
Aza-steroids are important class of compounds because of their numerous biological activities.

New study finds two amino acids are the Marie Kondo of molecular liquid phase separation
a team of biologists at the Advanced Science Research Center at The Graduate Center, CUNY (CUNY ASRC) have identified unique roles for the amino acids arginine and lysine in contributing to molecule liquid phase properties and their regulation.

Prediction of protein disorder from amino acid sequence
Structural disorder is vital for proteins' function in diverse biological processes.

A natural amino acid could be a novel treatment for polyglutamine diseases
Researchers from Osaka University, National Center of Neurology and Psychiatry, and Niigata University identified the amino acid arginine as a potential disease-modifying drug for polyglutamine diseases, including familial spinocerebellar ataxia and Huntington disease.

Alzheimer's: Can an amino acid help to restore memories?
Scientists at the Laboratoire des Maladies Neurodégénératives (CNRS/CEA/Université Paris-Saclay) and the Neurocentre Magendie (INSERM/Université de Bordeaux) have just shown that a metabolic pathway plays a determining role in Alzheimer's disease's memory problems.

New study indicates amino acid may be useful in treating ALS
A naturally occurring amino acid is gaining attention as a possible treatment for ALS following a new study published in the Journal of Neuropathology & Experimental Neurology.

Breaking up amino acids with radiation
A new experimental and theoretical study published in EPJ D has shown how the ions formed when electrons collide with one amino acid, glutamine, differ according to the energy of the colliding electrons.

To make amino acids, just add electricity
By finding the right combination of abundantly available starting materials and catalyst, Kyushu University researchers were able to synthesize amino acids with high efficiency through a reaction driven by electricity.

Nanopores can identify the amino acids in proteins, the first step to sequencing
While DNA sequencing is a useful tool for determining what's going on in a cell or a person's body, it only tells part of the story.

Read More: Amino Acids News and Amino Acids Current Events
Brightsurf.com is a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for sites to earn advertising fees by advertising and linking to Amazon.com.