Since forever, human beings have been fascinated by the unknown. We have made many discoveries on our planet. Satisfied, we moved on to the other place that caught our attention: space. But despite the breakthroughs we did and planned to do, there is one crucial question we, as a race, were not able to answer: how did life begin on Earth?
It is known that everything that has life is comprised of the same 20 amino acids. But did they combine to constitute the first protein molecules? A team of scientist believes that they might have found the response to the great question. The team from the Georgia Institute of Technology’s Center for Chemical Evolution did an experiment that demonstrated how the ancestors of the protein molecules formed a connection.
In their experiment, the researchers selected some amino acids, such as lysine, arginine, and histidine, and combined them with other three non-biological amino acids. Then, the researchers created the same conditions that had been present around 4 billion years ago, when life is believed to have started. After this, they put the amino acids in water in which they previously incorporated hydroxy acids, a component of water before life. The water was heated up to 85 degrees Celsius (185 F) until it evaporated.
How life on Earth emerged
The result was surprising. The biological, and not the non-biological, amino acids united with each other with the help of amines; they formed peptides which resembled the already existing proteins. Lysine, which was not believed to be able to create chains, actually succeeded in doing just that.
With these discoveries, the researchers could speculate that ready-made amino acids chains were present before life created proteins. Also, as only biological amino acids created chains, it is understandable why life is comprised of only 20 amino acids despite their number is way higher.
The scientists concluded that the amino acids that linked did that because they had a positive reaction with each other without many faulty outcomes. But they could not have been able to do so if it weren’t for the wet and dry cycles. This experiment also implicates that as amino acids link up with each other naturally, such reactions could have happened in other parts of the universe, which means that life could be possible in other solar systems.
Andre Blair s is the lead editor for Advocator.ca. He holds a B.A. in Psychology from the University of Toronto, and a Master of Science in Public Health (M.S.P.H.) from the School of Public Health, Department of Health Administration, at the University of North Carolina at Chapel Hill. Andre specializes in environmental health, but writes on a variety of issues.