Breeding Silicon-Carbon Bonds From Proteins Could be a Model of Future Alien Life
A group of scientists from the California Institute of Technology has managed to bring silicon to life for the first time by successfully breeding silicon-carbon bonds via proteins that are akin to human-made bonds.
The study, published in the journal Science, states that the scientists from Caltech managed to produce silicon-carbon bonds by breeding a bacterial protein. This breakthrough study changes the way that silicon-carbon bonds, which are widely used in pharmaceutical and agricultural industries, are made. Previously, the only way to produce silicon-carbon bonds is through synthetic reproduction.
"No living organism is known to put silicon-carbon bonds together, even though silicon is so abundant, all around us, in rocks and all over the beach," said Jennifer Kan, lead author of the new study, via Science Daily.
In order to naturally produce silicon-carbon bonds, the researchers used a method called directed evolution. The process, which was pioneered by Arnold in the 1990s, utilizes artificial selection to create new and improved enzymes in the lab.
Directed evolution begins by selecting an enzyme to be enhanced and then mutating its DNA coding in random ways until the desired trait comes out. After which, the "top-performing enzyme" undergoes multiple "evolutions" until scientists produce an enzyme that's better than the original.
The said process is similar to how agricultural animals and plants, such as cows and corns, are modified. It has also been used on household, pharmaceutical and fuel products.
However, different from previous processes, the study aims not just to improve an enzyme but force it to do something new -- breed silicon-carbon bonds. In order to pursuade an enzyme to breed, the group chose a protein called cytochrome c found in hot springs in Iceland. And after three rounds, the said enzyme has successfully created silicon-carbon bonds that are 15 times more efficient than those produced synthetically.
"We decided to get nature to do what only chemists could do -- only better," said Frances Arnold, principal investigator of the study. "It's like breeding a racehorse. A good breeder recognizes the inherent ability of a horse to become a racer and has to bring that out in successive generations. We just do it with proteins."
The new study shows how synthetically manufactured bonds could be made naturally in a more efficient and less expensive process.