How did life come about 4 billion years ago?Scientists have a lot of inferences.Recently, British scientists have synthesized a chemical compound that is essential for life under laboratory conditions that simulate the early Earth environment.This overturned previous speculations that the substance was not involved in the origin of life.The results were published in the journal Science on February 22.
British scientists synthesize key life-threatening substances in room-temperature water.Photo by UCL
CoA is the active fragment of coenzyme A, which is essential for metabolizing sugars, proteins and fats in animals and plays an important role in maintaining metabolism in living organisms.
Early studies failed to synthesize ubiquitinyl mercaptoethylamine effectively, leading to the belief that it may not have been involved in the origin of life.For example, the famous American biologist and chemist Stanley Miller, who studies the origin of life, synthesizes pantryl mercaptoethylamine in very low yields and extremely harsh reaction conditions – requiring extremely high concentrations of chemicals to be heated to 100 degrees Celsius.
Researchers at University College London used a different chemical reaction from Miller's experiment, using nitrile substances, hydrogen cyanide to form amino nitrile molecules instead of acid-driven reactions, resulting in the synthesis of panthenyl mercaptoethylamine in room temperature water.Hydrogen cyanide may have been abundant on early Earth.
Lead author Jasper Fairchild, PhD, Department of Chemistry, University College London, said: "It is nitrile that brings energy and selectivity.Our reaction is only carried out in water, which can efficiently produce pantryl mercaptoethylamine and requires relatively low concentrations of chemicals.”
Matthew Powner, professor of chemistry at University College London, who led the study, added: "What we learned in school was that these molecules should be made from acids, because using acids is biological.”
"Our study shows that this traditional view ignores an essential ingredient, the energy required to form new bonds."Powner says nitrile reactions look a little different, but the end product is indistinguishable.
The study also challenges the idea that life cannot have originated in water.Once ubiquitin mercaptoethylamine is synthesized in room temperature water, it's easy to imagine how it helped the first proteins and RNA molecules react chemically to form the first life forms 4 billion years ago.The reaction may have taken place in early Earth's pools or lakes, but it's unlikely to be in the ocean because the concentration of the chemical would have been diluted.
The researchers also used similar chemical methods to study how other key biological components, such as peptides and nucleotides, the basic structural units of RNA and DNA, were produced at the time of life's origin.
"It's easy to make different kinds of biomolecules with nitrile," Powner said, and the new study led him to believe that instead of just one molecule, RNA, the basic molecules of biology came together, a network of RNA, proteins, enzymes and more.
Future work will look at how these molecules bind together, for example, how panacyl mercaptoethylamine binds to RNA, peptides and lipids to undergo chemical reactions that cannot occur in a single class of molecules, he said.