янв 24, 2017
Biologists breed life form with lab-made DNA. Don't call it 'Jurassic Park'
For billions of years, life has danced that same old DNA jig. At some point after Earth's formation, but before bacterial slime formed the planet's oldest fossils 3.7 billion years ago
DNA became the system by which virtually every organism stored and passed on its genetic information. No matter how many times mutations or natural selection remixed the tune, four nitrogenous base units always comprised DNA: adenine, cytosine, guanine and thymine. This was as true for hairy apes as it was for brewer's yeast, redwoods and Tyrannosaurus rex.
Now, scientists led by the Scripps Research Institute in La
Jolla, Calif., have added two extra, artificial letters to the ancient
alphabet of A, C, G and T. And the E. coli living with this unusual
six-letter, three-base-pair alphabet are, by the account published Monday in the Proceedings of the National Academy of the Sciences, capable of surviving tough laboratory conditions.
In 2014, the synthetic biologists announced they had achieved something unprecedented in the history of DNA. They went beyond remixing the DNA music, mashing it up with an alien beat. It was the genetic equivalent of Danger Mouse's "Grey Album": Where other bands simply covered John, Paul, George and Ringo, someone figured out how to thread in Jay Z.
The biologists added two new letters to the four-letter DNA alphabet within E. coli bacteria. The scientists called the novel base units dNaM and d5SICS (a newer, improved version of the bases were named dNaM and dTPT3). You can think of these unnatural nucleobases as X and Y. Years down the line, microbes with increased genetic information could present exciting and lucrative scientific possibilities: bacteria capable of churning out therapeutic human proteins, or altered bugs that hoover up environmental spills.
The Whashington Post
By Ben Guarino