The chemistry of the origin of life, the way purely organic, carbon-containing molecules begin to bond to form large, self-replicating molecules like UKTN and form life, remains a mystery, but scientists believe this ancient transition from chemistry to biochemistry happened. in the ancient oceans of the earth.
But that presents a problem, a paradox. Even if biochemistry and organic life require liquid water, the chemical reactions needed to form life’s early building blocks cannot take place in a fully water-saturated environment — it seems Earth’s early oceans are just too wet. were to support the formation of molecules needed to create life.
That countless life forms, including humans, now exist is proof enough that life has found a way, and Purdue University Professor of Analytical Chemistry Graham Cooks may have solved the puzzle.
It turns out that “water is not wet everywhere,” he said in a media statement.
In a new newspaper published Monday in the Proceedings of the National Academy of Sciencesdescribe Dr. Graham and his Purdue colleagues Dylan Holden and Nicolas Morato presented the results of their research showing that the chemical reactions needed to form peptide molecules, essential molecules for life, can take place in tiny bubbles of water.
“We propose that the interface of aqueous microdroplets serves as a drying surface,” the trio write in the paper, that thin film between water and air provides just enough dryness for the important chemical reactions to take place.
The chemical reactions the researchers are working on are the joining of amino acids into larger, peptide molecules.
Amino acids are the building blocks of more complex biochemistry. Amino acids are simple, carbon-based molecules linked together in chains of up to 50 to form peptides. Longer chains of amino acids form polypeptides, which in turn are linked together to form proteins.
Amino acids can be formed by chemical reactions that do not involve and do not necessarily lead to the origin of life. For example, scientists believe that ancient meteorites seeded Earth with many amino acids made on asteroids in space, a fact recently confirmed by Japan’s Hayabusa 2 mission that returned samples of the asteroid Ryugu.
Once part of life, amino acids are crucial. The amino acids adenosine, cytosine, guanine and thymine make up the backbone of UKTN while polypeptides make up hormones like insulin and proteins like collagen help create the structure of our body.
But for amino acids to bind and form peptide chains, they must give up a water molecule — something scientists thought impossible in the wet world of the ocean.
But dr. Cooks and his colleagues at Purdue, Dylan Holden and Nicolas Morato, now show that the surface of the tiny droplets of water created by crashing waves or splashing streams provides an environment where amino acids can make those bonds, allowing larger molecules to be formed from amino acids.
“This is essentially the chemistry behind the origin of life,” said Dr. cooks. “This is the first demonstration that primordial molecules, simple amino acids, spontaneously form peptides, the building blocks of life, in droplets of pure water.”
Not only does this help solve the puzzle of how life could arise spontaneously from the ingredients present on the young Earth, it could aid human life more than 3 billion years later. It turns out that the amino acid-peptide binding reactions take place much, much faster in microdroplets than in a liquid solution, which could speed up drug development.
“The rates of reactions in droplets are somewhere between a hundred and a million times faster than the same chemicals reacting in bulk solution,” said Dr. cooks. “Using droplet chemistry, we built a device, which is now being used at Purdue, to accelerate the synthesis of new chemicals and potential new drugs.”