A step to artificial life: Manmade DNA powers cell

[cromagnon]

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A step to artificial life: Manmade DNA powers cell


AP – This undated handout image provided by the J. Craig Venter Institute shows negatively stained transmission …



By LAURAN NEERGAARD, AP Medical Writer Lauran Neergaard, Ap Medical Writer – Thu May 20, 7:54 pm ET
WASHINGTON – Scientists announced a bold step Thursday in the enduring quest to create artificial life. They've produced a [COLOR=#366388 ! important][COLOR=#366388 ! important]living [COLOR=#366388 ! important]cell[/color][/color][/color] powered by manmade DNA. While such work can evoke images of Frankenstein-like scientific tinkering, it also is exciting hopes that it could eventually lead to new fuels, better ways to clean polluted water, faster vaccine production and more.
Is it really an artificial life form?
The inventors call it the world's first synthetic cell, although this initial step is more a re-creation of existing life — changing one simple type of bacterium into another — than a built-from-scratch kind.
Maryland genome-mapping pioneer J. Craig [COLOR=#366388 ! important][COLOR=#366388 ! important]Venter[/color][/color] said his team's project paves the way for the ultimate, much harder goal: designing organisms that work differently from the way nature intended for a [COLOR=#366388 ! important][COLOR=#366388 ! important]wide [COLOR=#366388 ! important]range [/color][COLOR=#366388 ! important]of [/color][COLOR=#366388 ! important]uses[/color][/color][/color]. Already he's working with ExxonMobil in hopes of turning algae into fuel.
And the report, being published Friday in the journal Science, is triggering excitement in this growing field of synthetic biology.
"It's been a long time coming, and it was worth the wait," said Dr. [COLOR=#366388 ! important][COLOR=#366388 ! important]George [COLOR=#366388 ! important]Church[/color][/color][/color], a Harvard Medical School genetics professor. "It's a milestone that has potential practical applications."
The project has overcome some hurdles in engineering larger genomes that will help push forward the field, said biological engineer Dr. Ron Weiss, a Massachusetts Institute of Technology leader in synthetic biology.
"It's an important step," said Weiss. Even though the manmade [COLOR=#366388 ! important][COLOR=#366388 ! important]DNA[/color][/color] needed an already living cell to start working, eventually it reproduced and "all elements in the cells after some amount of time can be traced to this initial artificial DNA. That's a great accomplishment."
Scientists for years have moved single genes and even large chunks of DNA from one species to another. Venter aimed to go further. A few years ago, his team transplanted an entire natural genome, all of an organism's genes, one bacterium into another and watched it take over — turning a goat germ into a cattle germ.
Next, the researchers built from scratch another, smaller bacterium's genome, using off-the-shelf laboratory-made [COLOR=#366388 ! important][COLOR=#366388 ! important]DNA [COLOR=#366388 ! important]fragments[/color][/color][/color].
Friday's report combines those two achievements to test a big question: Could synthetic DNA really take over and drive a living cell? Somehow, it did.
"This is transforming life totally from one+ species into another by changing the software," said Venter, using a computer analogy to explain the DNA's role.
The researchers picked two species of Mycoplasma, simple germs that contain a single chromosome and lack the cell walls that form barriers in other bacteria. First, they chemically synthesized the genome of M. mycoides, that goat germ, twice as large as the germ genome they'd previously built.
Then they transplanted it into a living cell from a different Mycoplasma species, albeit a fairly [COLOR=#366388 ! important][COLOR=#366388 ! important]close [COLOR=#366388 ! important]cousin[/color][/color][/color].
At first, nothing happened. The team scrambled to find out why, creating a genetic version of a computer proofreading program to spell-check the DNA fragments they'd pieced together. The result: They found that a typo in the [COLOR=#366388 ! important][COLOR=#366388 ! important]genetic [COLOR=#366388 ! important]code[/color][/color][/color], in one of the synthetic genome's million chemical base pairs, was rendering the manmade DNA inactive, delaying the project three months to find and restore that bit.
"It shows you how accurate it has to be, one letter out of a million," Venter said.
That fixed, the transplant worked. The recipient cell started out with synthetic DNA and its original cytoplasm, but the new genome "booted up" that cell to start producing only proteins that normally would be found in the copied goat germ. It reproduced into a small colony of germs in a [COLOR=#366388 ! important][COLOR=#366388 ! important]lab [COLOR=#366388 ! important]dish[/color][/color][/color]. The researchers had tagged the synthetic DNA to be able to tell it apart, and confirmed that those new ones really looked and behaved like M. mycoides, not the recipient cell

someone post before that this is imposible ..

to create the first single cell... he said mag patuli cya ug usab ,, i wonder asa na kaha to cya.

[rodsky]

YouTube - Craig Venter unveils "synthetic life"

-RODION

[noysabas]

diba plano mani ni hitler?

[hitch22]

This is another big step since the Miller-Urey experiment in the 1950s to create life (i.e. living cells) from inorganic precursors...in other words, creating life from non-life. When Venter (who also headed the successful human genome project together with Francis Collins) announced this groundbreaking achievement, other scientists pointed out that Venter merely copied an existing bacterial genome and then inserted it into another bacterium to create the synthetic cell. Yes, yes..but assembling a cell and giving it life? That's still astonishing. One thing's for sure, we're getting closer to that ultimate goal. The implications to our understanding about the origins of life on earth, even at this stage, is stunning. I think you all know what I mean.

[coolnezz]

If figuring out how to quickly sequence genomes was but the first small step for genetics, Craig Venter has gone ahead and made a giant leap for the discipline. The J. Craig Venter Institute announced today that it has created the world’s first synthetic cell, boasting a completely synthetic chromosome produced by a machine.

“This is the first self-replicating species we’ve had on the planet whose parent is a computer,” Venter said in a press conference.

The biological breakthrough could have myriad applications, as it essentially opens the door to engineered biology that is completely manipulated by laboratory scientists. The researchers are already planning to create a specially engineered algae designed to trap carbon dioxide and convert it to biofuel. Other applications could include medicine, environmental cleanup, and energy production.

Though a bacteria cell was the final product in this particular experiment, eukaryotic yeast was a critical player in the process. Venter and company synthesized the genome of the bacterium M. mycoides by taking short strains of DNA (contemporary machines can only assemble short sequences at a time) and inserting them into yeast, whose enzymes have a keen ability to repair DNA and combine the short strains together.

The yeast first linked the shorter snippets (just over 1,000 base pairs each) together into longer 10,000 base pair strands. The longer strands were removed, further combined in groups of ten and put back into yeast to connect 100,000 base pair strands. After three rounds of this, the team had produced the full genome, stretching more than a million base pairs. To distinguish their synthetic genome from those found in nature, special “watermark” sequences were added to the DNA so that it won’t be mistaken for a natural species.

The synthetic genome was then transplanted into another type of bacteria, Mycoplasma capricolum, where the synthetic genome started producing new proteins. The capricolum’s original genome was either destroyed by M. mycoides' enzymes or lost during cell replication. Either way, as the cells multiplied, cells were produced borne solely of the synthesized genome and there it was in the petri dish: the world’s first synthetic cells built from wholly synthesized DNA.

How to Build a Synthetic M. Mycoides Cell: JCVI

“Every component in the cell comes from the synthetic genome,” Venter said. “This cell, its lineage is a computer. But this cell is simply a proof of concept to get to the minimal understanding of the synthetic genome.”
Not everyone is thrilled with the achievement, however. Upon the announcement, some researchers questioned the validity of the term "synthetic cell" because though the genome was fabricated by computer, the process merely modified existing life rather than created it from scratch. There are also plenty ethical – and legal – ramifications to such a technological advance that will no doubt be argued in coming months.

What is not up for dispute is that Venter and company have carried out a serious technological feat in stringing together a million nucleotide base pairs to create a complete genome in the lab. Not only that, but they did it accurately enough that the cell accepted the DNA.
"Probably 99% of our experiments have failed," Venter said of the decades-long journey to this point.

"This was a debugging, problem solving process from the beginning, because there was no recipe."
Now that there's a recipe, Venter and company want to get cooking. Having strung 1 million base pairs into a coherent genome, Venter said the next step is algae, as algal genomes generally contain just under 2 million base pairs. By comparison, the human genome contains more than 3 billion pairs, so don't look for synthetic mammals any time soon.

Researchers Create the World's First Fully Synthetic, Self-Replicating Living Cell | Popular Science

[Peenut]

Could this be successful?...I wonder

[rodsky]

Could this be successful?...I wonder

"Could"? It already is.

-RODION

[gabs]

hala ka NICE ani oi. mao na tingale ni start sa computing using dna.