Bacteria ready to make plastic from sugar

Claims of biology-based oil and plastic usually bear the caveat "in five years." But a San Diego-based company claims they will have a pilot plant for production of E. coli-based 1,4 butanediol (BDO), the base chemical for plastic products ranging from Spandex to car bumpers, next year.

"We are able to couple the growth of the organism to the production of BDO," said Christophe Schilling, co-founder of the company, Genomatica. "For the bacteria to grow they have to produce BDO."

The announcement holds particular promise amid rising oil prices and a scramble to replace petroleum-based ingredients with renewable ones.

Traditionally, BDO is made from oil and natural gas through an energy-intensive process. Genomatica, founded in 2000, says their technology can significantly reduce the cost of making BDO. All they need is sugar and a particular bacterium.

The specific cost saving will vary by company, but Chris Gann, Genomatica's CEO, says that, "if the price of oil dropped to $50 per barrel [our technology] would still be competitive." The price for a barrel of oil earlier this week was about $120.

That savings in cost comes from using cheaper raw materials and less energy to trigger the chemical reactions necessary to turn oil into plastic, Gann said.

Using computer-aided design (CAD) software similar to what engineers have used for years, Genomatica scientists simulated various chemical reactions to find the best genes for the job.

Schilling won't say from which specific organisms they got the proteins and enzymes used to turn sugar into BDO, other than that they culled them from a computer database of "hundreds of microorganisms," some obscure, some commonplace.

Once Genomatica scientists had a working virtual E. coli, they spliced the selected genes into the real E. coli and turned them loose on raw cane sugar.

So far, Genomatica has produced less than two pounds of BDO. To create industry-scale amounts of BDO, cane sugar, E. coli and water will go into 105-degree (Fahrenheit) fermentation tanks, like the ones used to produce ethanol.

Still, cells are notorious for evolving unwanted traits, like the rise of drug resistant bacteria and cancers. Schilling said they plan to tap into that evolutionary bent and turn it into profit.

"We have ways to essentially accelerate [evolution], so the bacteria can evolve to tolerate higher concentrations of BDO and not in the exact way we would have predicted with the computer models," said Schilling.

Genomatica will make the E. coli, but not at the plants where the BDO is produced. Instead, the company will license the genetically engineered E. coli to companies worldwide who create BDO-based products. The company can even custom design E. coli that take advantage of local sugar variations. The first pilot plant is set for next year, according to Genomatica.

Next year might be a bit ambitious, suggested Harvey Blanch, a professor of chemical engineering at the University of California, Berkeley. Blanch said a longer time line, as in a couple of years, was more likely, but that he was still quite excited by the development.

"This is a very interesting opportunity to get a new source of raw materials that could replace chemical processing with biological engineering," said Blanch. "Using this technique everything from new kinds of plastics to jet fuel could be produced with less energy and smaller environmental costs."

Genomatica hopes that bio-BDO is just the first of these new raw materials. Currently, the company is pursuing more than six other unspecified chemicals, all of which have a larger market than the $4 billion annual BDO market.

"What gets us really excited is that this opens up the door to go after other chemicals that aren't produced in nature," said Schilling.
MSNBC