Apr 12, 2023 06:00:00

A study investigating ``Why are there only about 20 types of amino acids that make up proteins?'' Reveals hints about the evolution of organisms

It is said that life on earth was born about 3.8 billion years ago, and how life was born from the primitive earth is

a major scientific theme . Research teams such as Prague Charles University in the Czech Republic and Johns Hopkins University in the United States investigated how the proteins that form life were synthesized on the primitive earth, about 20 kinds of protein constituents Some of the mysteries of why these amino acids were selected and how the combinations of amino acids affected subsequent life have been clarified.

Early Selection of the Amino Acid Alphabet Was Adaptively Shaped by Biophysical Constraints of Foldability | Journal of the American Chemical Society
https://doi.org/10.1021/jacs.2c12987

Ancient proteins offer new clues about origin | EurekAlert!
https://www.eurekalert.org/news-releases/980966

Evolution Could Predate Life Itself, Protein Discovery Suggests : ScienceAlert
https://www.sciencealert.com/evolution-could-predate-life-itself-protein-discovery-suggests

Did evolution occur before life even existed? New study sheds light on how amino acids 'evolved' | Salon.com
https://www.salon.com/2023/03/01/first-life-on-earth-amino-acid-study/

Of all the amino acids, 22 are the building blocks of proteins , of which 21 in eukaryotes and 20 in most animals, including humans. If amino acids are compared to letters, proteins are words that are made by rearranging letters, and life is a sentence that is made up of words.

All life on earth, from humans to bacteria and archaea, is composed of a combination of about 20 amino acids in common. These amino acids are thought to consist of 10 types of 'early amino acids' selected from the atmosphere of the primitive earth and fragments of meteorites, and 10 types of 'late amino acids' added later. However, it is unknown why only about 20 amino acids were selected from over 500 naturally occurring amino acids.

Therefore, a research team led by Johns Hopkins University biophysicist Stephen Freed and his team reproduces in the laboratory various combinations of amino acids that were abundant on the earth before life began, mimicking primitive protein synthesis. I did an experiment.

Experiments have shown that ancient organic compounds selected and incorporated the optimal amino acids for protein

folding . Protein shape and folding are critical to protein function as they determine how they interact with other molecules and the surrounding environment. The research team believes that the 10 late amino acids, which were added later, were selected as building blocks because they were better at performing the function of the protein.

Science Alert, a scientific media, said, 'In other words, it can be said that evolution and natural selection were progressing at the stage of protein synthesis. The most suitable amino acid was selected for

“Achieving Darwinian evolution requires sophisticated methods of turning genetic molecules like DNA and RNA into proteins,” Fried said. There's the egg-first problem: our work reveals that, before Darwinian evolution, nature was able to select building blocks with useful properties.' Folding enabled the evolution of life before life existed on Earth: it enabled evolution before biology existed, and it enabled natural selection of chemicals useful for life before DNA existed. It was,” he commented.

This research suggests not only the origin of life on Earth, but also the possibility of life existing on other planets. ``The universe seems to love amino acids,'' Fried said.