Mankind has always tried to solve the mystery of life. In fact, over the years, scientists have developed many scenarios. And now researchers at Purdue University believe they have found the answer to one of the most important questions that have always remained unanswered. How could primordial molecules spontaneously form the building blocks of life? How did life arise on Earth? Scientists – and not only scientists – have been asking this existential question for almost as long as we can remember. Over time and through their studies, they have concluded that life originated in the oceans, but without being able to explain the chemical mechanisms that led from primordial molecules to the building blocks of life. Today, chemists at Purdue University (USA) are solving the mystery.
To understand this, it is probably necessary to point out that crude amino acids, primordial molecules that may have been brought to Earth very regularly by meteorites, can react to form peptides – the building blocks of proteins and thus of life. But this process requires the loss of a water molecule. This is hard to imagine in an environment as humid as the oceans in which researchers believe – and the evidence confirms – that life originated on our planet.
To develop, life seems to need both an environment with water and one without water! It is this dilemma that the chemists at Purdue University seem to have solved. The essence of their solution? “Water is not wet everywhere. Understand that where a drop of water meets the atmosphere, incredibly fast reactions can occur. Reactions that bind anionic acids into peptides.
The researchers came to this conclusion after no less than a decade of studying chemical reactions in water droplets with mass spectrometers. “The reaction rate in droplets is 100 to a million times faster than the reaction of the same chemicals in a ‘bulk solution,'” said Graham Cooks, professor of chemistry, in a Purdue University press release.
“We have shown for the first time that primordial molecules, simple amino acids, spontaneously form peptides, the building blocks of life, in droplets of pure water – without a catalyst. This is an amazing discovery. It shows that the beginning of the history of life on Earth is probably found in the mist that flies through the air or the waves that hit the earth, or even where freshwater flows down.
And while this work could no doubt also shed light on the search for life elsewhere in the universe, it could also revolutionize scientists’ understanding of chemical synthesis. An understanding which is crucial for those developing new treatments for diseases, for example. “The experiments of synthetic chemists are so slow… But droplet chemistry is a game changer,” explains Graham Cooks. “But droplet chemistry is game-changing,” explains Graham Cooks, “so we can imagine a significant acceleration of the synthesis of new chemicals and potentially that of new drugs.