Posted on 02/27/2019 5:29:17 PM PST by Tolerance Sucks Rocks
The DNA of life on Earth naturally stores its information in just four key chemicalsguanine, cytosine, adenine and thymine, commonly referred to as G, C, A and T, respectively.
Now scientists have doubled this number of lifes building blocks, creating for the first time a synthetic, eight-letter genetic language that seems to store and transcribe information just like natural DNA.
In a study published on 22 February in Science, a consortium of researchers led by Steven Benner, founder of the Foundation for Applied Molecular Evolution in Alachua, Florida, suggests that an expanded genetic alphabet could, in theory, also support life.
Its a real landmark, says Floyd Romesberg, a chemical biologist at the Scripps Research Institute in La Jolla, California. The study implies that there is nothing particularly magic or special about those four chemicals that evolved on Earth, says Romesberg. Thats a conceptual breakthrough, he adds.
Normally, as a pair of DNA strands twist around each other in a double helix, the chemicals on each strand pair up: A bonds to T, and C bonds with G.
For a long time, scientists have tried to add more pairs of these chemicals, also known as bases, to this genetic code. For example, Benner first created unnatural bases in the 1980s. Other groups have followed, with Romesbergs lab making headlines in 2014 after inserting a pair of unnatural bases into a living cell.
But the latest study is the first to systematically demonstrate that the complementary unnatural bases recognise and bind to each other, and that the double helix that they form holds its structure.
(Excerpt) Read more at scientificamerican.com ...
Something like this was reported a couple of years back, with the addition of two unnatural groups that base-paired reasonably specifically, to give a total of six “letters” to the genetic alphabet. Don’t know if much of anything practical was done with it; it was largely an experimental demonstration of a theoretical concept.
I’ll stick with the garlic, cilantro, anise, and thyme.
I suspect that they’ll insinuate them into some innocent bacteria, coopting their protein-building machinery, see what pops out, etc.
The protein is already folding while more amino acids are being added. So its not the same level of randomness as if you had the entire string ready and just let it go.
>That is, do they make proteins?
Probably, but they wouldn’t necessarily use the installed base of proteins that has been built up over billions of years of trial and error.
Use the same analogy as to why the width of railroads tracks is what it is.
So far so good.
For a long time, scientists have tried to add more pairs...
That's what got us into this mess.
RSTLNE
“The study implies that there is nothing particularly magic or special about those four chemicals that evolved on Earth”
Right, OK. So you COPIED an architecture from another design and can now claim the design is not particularly “magic”.
Yet you walk around the room, doing your research ... running on those boring old chemicals.
No, Nancy would be a retrograde DNA structure, missing a few links along the chain.
Well, it’s actually seven letters. RNA has a U (uracil) in place of the T (thiamine).
Kinda dumb news. Uracil also occurs in nature.
I doubt that they would form any codons at all, since the tRNAs bind to specific codons. They could bind tRNAs, I suppose, if they had the same H bond patterns on their edges as natural DNA bases. But then, why would one need non-naturally occurring bases?
If you wanted to create a whole genetic system—the base pairs, tRNAs that recognize the triplets, enzymes to charge the tRNAs with novel amino acids—I suppose that is possible as an academic exercise. Not sure how useful it would be.
To paraphrase Taylor Swift, cause we dont know what we dont know...
That’s going to play hell with the movie “GATTACA”.
______
So what will they call Gattaca II?
And will anybody be able to pronounce it?
“synthetic” may simply mean “unrecognized at the time”.
Artificial is not necessarily a synonym...
Would there be any interesting 2o structures in the proteins from any new amino acids (etc. etc.)
All of which is to say something of a sensitivity analysis on the system as it exists, is the optimal or near optimal for forming animal/human proteins, compared to other, umm, ingredients (assuming the same general form DNA--> tRNA --> amino acid --> protein)?
...and would the current proteins which unzip and stabilize DNA (and correct mistranscriptions) work as well on the DNA with 8 base pairs?
Ah....no. Words have meaning.
This movie never ends well.
Scientists shouldnt try to play God as they tinker with what they think is an Intelligent Design.
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