Where does life come from? Scientists reveal the mystery of the origin of life

According to Science Daily, at the beginning of all things, there were only simple chemicals, and then amino acids were produced The latter eventually formed the proteins necessary to create a single cell, and then the single cell gradually formed plants and animals Recent studies have revealed how primordial soup creates amino acid building units, and a common scientific consensus has been reached on the evolution from single cell to plant and animal However, how these building units were originally assembled into proteins remains a mystery Now, two scientists at the University of North Carolina, Richard Wolfenden and Charles Carter, offer new insights into the transition from building units to life four billion years ago The world at the beginning of all things is desolate "Our research shows that from the very beginning, well before the formation of large mature molecules, the close relationship between the physical properties of amino acids, genetic codes and protein folding is very important." Said Carter, a professor of Biochemistry and Biophysics at the University of North Carolina School of medicine "This close interaction is likely to be a key factor in the evolution from building blocks to organisms." The article, published in the journal Proceedings of the National Academy of Sciences, ignores the current problematic "RNA world" theory, which holds that RNA, a molecule that plays a role in gene coding, regulation and expression, is raised from a primitive soup of amino acids and cosmic chemicals, which for the first time produces shorter proteins called peptide bonds, which are then produced Single cell organics were produced Wolfenden and Carter argued that RNA does not fight alone In fact, the more likely scenario is that it is not RNA that catalyzes the formation of peptide bonds, but peptide bonds that catalyze the formation of RNA The discovery adds new knowledge to how life evolved billions of years ago Luca, the last common ancestor of all living things on earth The scientific community realized that there was Luca, the last common ancestor of all life on earth, 3.6 billion years ago It is likely to be a single cell organism with hundreds of genes, and has completed the blueprint of DNA replication, protein synthesis and RNA transcription It has all the basic components of modern organic matter, such as lipids After Luca's timeline, it's easy to understand how life evolved However, there is no conclusive evidence about how the primordial soup of boiling chemicals on earth - which existed 4.6 billion years ago after the earth was created - produced Luca These chemicals interact to form amino acids, which are still the basic building blocks of proteins in modern cells "We've learned a lot about Luca, and now we're starting to understand the chemical mechanisms that produce building blocks, such as amino acids, and now there's a desert of knowledge between the two." Carter said "We don't even know how to explore the desert." Now, the latest research from the University of North Carolina symbolizes the desert's border villages "Dr Wolfenden identified the physical properties of 20 amino acids, and we found a correlation between these physical properties and the genetic code." Carter said "This correlation suggests that the existence of a second, earlier code makes peptide RNA interaction possible, which is necessary to produce a natural selection that eventually led to the creation of the first life on earth." So, according to Carter, RNA doesn't come out of the original soup On the contrary, it is more likely that the interaction between amino acids and nucleotides, which results in the co production of protein and RNA, existed even before the cells existed Protein evolution: from simple to complex Proteins must be folded in a specific form to function properly Wolfenden's first paper, published in the proceedings of the National Academy of Sciences, showed that the polarity of 20 amino acids (how they are distributed between water and oil) and their size help explain the complex process of protein folding when an interconnected chain of amino acids self arranges to form a special three-dimensional structure with specific biological functions "Our experiments show how the polarity of amino acids changes continuously over a range of different temperature ranges, ensuring that the basic relationship between genetic coding and protein folding is not disturbed." Said Wolfenden This is very important, because when life on earth was first formed, the temperature of the earth was very hot, probably hotter than now or when the first animals and plants were produced A series of biochemical experiments on amino acids carried out in Wolfenden laboratory showed that two characteristics - the size and polarity of amino acids - are necessary and sufficient conditions to explain the characteristics of amino acids in folded proteins, and these relations still hold even when the environmental temperature of the earth sphere was higher 4 billion years ago Dr Wolfenden is currently in the Department of chemistry at the school of art and science, University of North Carolina, Chapel Hill The second paper, led by Carter and published in the Journal of the National Academy of Sciences, studies in depth how an enzyme called aminoacyl tRNA synthetase (AARS) recognizes tRNA (also known as tRNA) These enzymes translate the genetic code "Think of tRNA as an adapter," Carter said "One end of the adapter carries a specific amino acid, while the other reads the genetic blueprint for that amino acid in messenger RNA Each synthetase matches these 20 amino acids to their respective adaptors, allowing the genetic blueprint in messenger RNA to produce the right protein each time " Carter's analysis showed that both ends of L-shaped tRNA molecules contain independent codes or criteria, which specify which amino acid to choose One end of the transfer RNA carrying amino acids will sort and classify amino acids according to the size of amino acids, while the other end of the L-shaped transfer RNA molecule is called tRNA anti codon, which will read the codon, which is the three RNA nucleotide sequences in the genetic information, and they will select amino acids according to the polarity Wolfenden's and Carter's studies suggest that the relationship between the physical properties of tRNAs and amino acids - their size and polarity - was crucial during the earth's primordial soup According to Carter's previous research on the small active core of tRNA synthetase called urzymes, it is likely that the choice of size is prior to the choice of polarity This sequential selection means that the earliest proteins are not necessarily folded into unique shapes, and their unique structures are likely to evolve later "Translating genetic codes connects pre life chemistry and biology," Carter said He and Wolfenden believe that the intermediate stages of gene coding help solve two Mysteries: how complexity comes from simplicity, and how life distributes labor between two different polymers, proteins and nucleotides "The fact that genetic code is produced in two successive processes - the first relatively simple - may be one of the reasons life can be produced when the earth is very young." Wolfenden explained An earlier encoding - which prompted the earliest encoding of peptide bonds linked to RNA - may provide a decisive selection advantage This primitive system may have undergone a process of natural selection, thus resulting in the evolution of a new biological form "The cooperation between RNA and peptide bonds is likely to be necessary for the spontaneous generation of complexity," Carter added "In our view, the earth used to be a peptide bond RNA world, not just a RNA world." The study was funded by the National Institutes of Health (NIH).