WEST LAFAYETTE, Indiana— Life on Earth may have started with a chemical ‘Big Bang’ – in a drop of water, according to new research. Researchers from Purdue University say this event in early Earth chemistry caused reactions up to a million times faster than normal, kickstarting evolution.
The discovery has a host of implications, from accelerating drug development to searching for extraterrestrial life on other worlds.
“It’s basically the chemistry behind the origin of life,” says Graham Cooks, Henry Bohn Hass Professor Emeritus of Analytical Chemistry at Purdue’s College of Science, in a press release. “This is the first demonstration that primordial molecules, simple amino acids, spontaneously form peptides, the building blocks of life, in droplets of pure water. It is a dramatic discovery. »
Water-based chemistry led to the formation of proteins and life on Earth. It may hold the key to better drugs for humanity’s most debilitating diseases, researchers say. The radical theory suggests that life happened all of a sudden, in a chemical explosion. It has long been thought that the ingredients come together slowly, bit by bit.
“The rates of reactions in droplets are a hundred to a million times faster than the same chemicals reacting in a bulk solution,” Cooks says.
Accelerating these reactions makes catalysts unnecessary. Understanding how this process works would be the “holy grail” of chemistry. The new findings shed light on why life developed on Earth and inform its search for other planets or moons.
Unraveling the life-creating mystery of the oceans
For decades, scientists theorized that life began in the oceans, but the chemistry has remained an enigma. When Earth formed 4.5 billion years ago, it was a barren ball of rock, battered by meteorites and covered in erupting volcanoes.
Over a billion years, it became inhabited by microorganisms. Today, life covers every inch of the planet, from the highest mountains to the deepest seas. However, all other worlds in the solar system seem lifeless. What happened to cause the barren rocks, sand and chemicals to give rise to life has baffled the greatest minds.
Raw amino acids – something meteorites provide from the cosmos – can react and lock together to form peptides. Curiously, these building blocks of proteins and life also require the loss of a water molecule. It is highly unlikely in a humid, watery or oceanic environment. For life to form, water was needed, but it also needed space away from water.
Early Earth chemistry expert Professor Cooks and his colleagues have now discovered the answer to the riddle. They have spent more than 10 years using mass spectrometer scanners to analyze chemical reactions in water-containing droplets.
“The water is not wet everywhere,” says Professor Cooks.
At the margins, where a droplet meets the atmosphere, incredibly fast reactions can take place, transforming abiotic amino acids into the building blocks of life. Places where sea spray flies through the air and waves pound the land, or where fresh water rushes down a slope, were fertile landscapes for the potential evolution of life.
Could this discovery lead to new drugs?
Understanding how amino acids turned into proteins and eventually life forms could revolutionize chemical synthesis. Faster responses are key to discovering and developing new drugs and therapeutic treatments for life-threatening diseases.
“If you walk through a college campus at night, the buildings with the lights on are where the synthetic chemists work,” Cooks concludes. “Their experiments are so slow that they go on for days or weeks at a time. It’s not necessary, and using droplet chemistry, we’ve built a device, which is currently in use at Purdue, to speed up the synthesis of new chemicals and potential new drugs.
The study is published in Proceedings of the National Academy of Sciences.
South West News Service writer Mark Waghorn contributed to this report.