Life on Earth might have started in tiny droplets
The question of how life on Earth came about for the first time remains shrouded in mystery. We know water is necessary for life, but there are also some chemical reactions required for life that are prohibited by the presence of water.
Now, a new study has shown that mini water droplets might have solved this ‘water problem’.
“You and I are alive because of phosphorus and phosphorylation,” says Richard Zare, a professor of chemistry at Stanford University and one of the paper’s senior authors. “You can’t have life without phosphorous.”
Phosphorous is in DNA, RNA and ATP, which stores energy in our cells. But when it comes to producing phosphorous, water gets in the way. When considering how phosphorus formed in the first place, a lot of theories have been proposed, including heat from nuclear reactions or phosphorous landing on Earth from somewhere in space.
But Zare and his colleagues have shown if water was in the form of microdroplets, made when waves crashed onto the shore, for example, the water problem would not be a problem any more. These mini droplets have a much larger surface area to volume ratio than a large volume of water, and this means the phosphorylation reactions can actually occur.
The researchers sprayed tiny droplets of water, along with phosphorous and other chemicals, into a chamber. After analysing the results, they found several molecules containing phosphorous had spontaneously started to grow without any catalyst to start the reaction.
“I don’t think we’re going to understand exactly how life began on Earth,” says Zare. This is because no one can go back in time to watch what happened as life emerged, and there is no good fossil record for the formation of biomolecules. ”But we could understand some of the possibilities.”
The new study is published in the Proceedings of the National Academy of Sciences.