A Better Biofuel

A California biotech company is engineering microbes to produce cheap biofuels that could outcompete ethanol.

Stroll the streets of San Francisco and you're likely to overhear someone talking about biofuels. It's the latest technology wave to hit the Bay Area, and scientists and investors are swarming toward any startup claiming a better way to make ethanol or biodiesels. Amyris Biotechnologies may actually have found one. Having previously reengineered microbes so that they would produce a malaria drug, the company is now drawing on its expertise at creating efficient bacterial factories to cheaply churn out novel types of biofuels.

Amyris is one of the first companies to spring from the relatively new field of synthetic biology. Unlike the conventional genetic engineering currently used in the manufacture of antibiotics and protein drugs such as insulin, synthetic biology involves hacking the entire metabolic system--changing the structure of some proteins, altering the expression of others, and adding in genes from other organisms--to create an efficient microbial machine. "We think of biological components as parts you assemble and try to get to function as a whole," says Jay Keasling, a bioengineer at the University of California, Berkeley, and one of Amyris's cofounders.

Plants and microbes naturally make small quantities of chemicals called terpenoids, which are the precursors of myriad products, including some pharmaceuticals and fuels. Several years ago, after developing new ways to boost bacteria's production of terpenoids, Keasling and three of his postdoctoral students founded Amyris to commercialize their work.

For its first project, the company selected artemisinin, a potent malaria drug derived from the sweet wormwood tree (see TR10 2005). By tinkering with yeast's metabolic processes, Keasling and his colleagues were able to boost its production of an artemisinin precursor a million-fold. After just two years of work, they are close to meeting their final goal for the drug--producing it in industrial quantities at prices affordable to developing nations. Now, having created microbial factories that can cheaply churn out carbon-based molecules, the group has turned its attention to biofuels.[read more]