from the I-for-one-welcome-our-new-silicon-overlords dept.
A new study is the first to show that living organisms can be persuaded to make silicon-carbon bonds—something only chemists had done before. Scientists at Caltech "bred" a bacterial protein to have the ability to make the man-made bonds, a finding that has applications in several industries.
Molecules with silicon-carbon, or organosilicon, compounds are found in pharmaceuticals as well as in many other products, including agricultural chemicals, paints, semiconductors, and computer and TV screens. Currently, these products are made synthetically, since the silicon-carbon bonds are not found in nature.
[...] The ideal candidate turned out to be a protein from a bacterium that grows in hot springs in Iceland. That protein, called cytochrome c, normally shuttles electrons to other proteins, but the researchers found that it also happens to act like an enzyme to create silicon-carbon bonds at low levels. The scientists then mutated the DNA coding for that protein within a region that specifies an iron-containing portion of the protein thought to be responsible for its silicon-carbon bond-forming activity. Next, they tested these mutant enzymes for their ability to make organosilicon compounds better than the original.
After only three rounds, they had created an enzyme that can selectively make silicon-carbon bonds 15 times more efficiently than the best catalyst invented by chemists. Furthermore, the enzyme is highly selective, which means that it makes fewer unwanted byproducts that have to be chemically separated out.
"This iron-based, genetically encoded catalyst is nontoxic, cheaper, and easier to modify compared to other catalysts used in chemical synthesis," says Kan. "The new reaction can also be done at room temperature and in water."
The source paper is available as well.
(Score: 2, Interesting) by Anonymous Coward on Wednesday November 30 2016, @02:27AM
The paper seems to be behind a paywall at the Science site. I only found the supplements for the source paper at the caltech link. There I saw lots of excel charts with no error bars.
For what it is worth, in the paper I see they did the experiment only 3 times (unblinded, and it sounds like using the same e coli lysate?). Also, from figure 1D, the WT lysate seems to be just as active as the "best catalyst invented by chemists". Combined with the fact this is a heme phenomenon, this got me wondering whether the mutations instead were increasing cooperativity* between the enzymes, or affect their expression. I didn't look very closely but didn't see any discussion of this alternative possibility using a few quick searches.
*https://en.wikipedia.org/wiki/Cooperativity
(Score: 0) by Anonymous Coward on Thursday December 01 2016, @05:54AM
http://scihub22266oqcxt.onion/http://science.sciencemag.org/content/354/6315/1048.full [scihub22266oqcxt.onion]
(Score: 0) by Anonymous Coward on Wednesday November 30 2016, @03:31AM
title sayzzz all.
(Score: 0) by Anonymous Coward on Wednesday November 30 2016, @06:03AM
That's what is meant by the "Selection" in "Evolution by Variation and Selection".
Last I checked, human brains are perfectly capable of participating in the selection process, just like anything else...
(Score: 2) by DeathMonkey on Wednesday November 30 2016, @07:37PM
Semantically correct but essentially meaningless. The best kind of correct!!
Yeah, it's the selection that's directed.