Venter Takes Step Toward Synthetic Cells

A team led by Craig Venter, the maverick geneticist best known for his fight to sequence the human genome, has moved a step closer to making cells from scratch. But huge hurdles remain to making practical use of this new technology.

The team at the J. Craig Venter Institute took all of the genes from one species of bacteria, Mycoplasma mycoides, and transferred them into another, Mycoplasma capricolum. The result: The genes from the mycoides took over, changing the cells from one species to another simply by moving around DNA.

However, experts say it will be very difficult to apply the technique to other types of bacteria, and for now its use may be limited to the fragile and tiny mycoplasma germs.

This research, published in the new issue of Science magazine, is part of a larger quest by Venter and his team to create a cell with a genome designed from scratch. The idea is that researchers could chemically synthesize the DNA they wanted outside the cell--something companies like Codon Devices of Cambridge, Mass., or Blue Heron Biotechnology of Bothell, Wash., can already do relatively cheaply--and implant it into bacteria, effectively creating a new species that did not exist before.

"With this new bacterial genome transplantation technique, we are now one step away from taking a newly constructed genome and transplanting it into a recipient cell," says Drew Endy, a synthetic biologist at MIT who did not work with the Venter team.

Jay Keasling, a synthetic biologist at University of California-Berkeley, calls the work "an indication that it will one day, perhaps soon, be possible to create an organism with a completely synthetic genome."

Researchers hope that custom-engineered cells could be useful in producing new types of medicines, including bacteria designed to help the body attack disease, or to produce biofuels that could help ease the world's reliance on oil. Such applications are far off, and no fully synthetic organism has yet been created.

Companies are already being started to take advantage of new technology that makes it easier to bioengineer organisms. Codon, of which Endy is a director, is looking to sell synthetic biology tech to other firms. Venter's own firm, Synthetic Genomics, is aiming to solve problems related to energy and recently signed a deal with British Petroleum (nyse: BP - news - people ). Amyris Biotechnologies, founded by Keasling, is looking to solve both health-related and energy problems. A company called LS9 is looking to use synthetic bacteria to make fuels.

Only the Venter team has married its approach so closely to creating life from scratch. Other researchers are marveling at the potential to do genetic engineering by modifying multiple machines at once, allowing them to work with cells as if they were machines. Amyris, for instance, has worked to solve a key production problem needed to make cheap malaria drugs.

But the Venter approach is more audacious and more costly. On a conference call with the press, he said that ideally, someday, he'd like to have all the components for a living cell in a chemical soup and then see them assemble. Now he has shown that it is possible to take a genome from one organism and move it to a similar one. The next step would be to manufacture a genome and transplant that.

Other synthetic biologists are taking existing cells and making hot rods; Venter wants to make one from scratch. But there are big drawbacks to his approach. His researchers are working with mycoplasma, a bacteria that has only 500 genes, close to the minimum number necessary. Mycoplasma is fragile, especially compared to the E. coli and yeast other synthetic biologists work with.

It also may be costly, with the estimated cost to reach the first synthetic organism being at least $10 million, according to a slide presented at a recent scientific conference by Hamilton Smith, the Nobel laureate who is heading the Venter Institute's synthetic biology effort. Venter's spokeswoman did not return an e-mail checking the accuracy of that figure.

George Church, a Harvard biologist who is a co-founder of LS9 and Codon Devices, argued that it was "not clear" that creating a wholly engineered cell, especially a fragile mycoplasma, would be more cost effective than just inserting or changing a few genes.

However, he says a related charge, that Venter is restricting biology and setting up a potential monopoly by patenting some of his institute's earlier work with Mycoplasma, is a "tempest in a teapot." Other researchers will still have plenty of room to invent their own work, and the patent does not, as some have asserted, cover the creation of any synthetic organism.