THERE are, at the moment, four likely winners in the biofuel race.

My information was culled from Science, October 24, 2008 and Nature, January 3, 2008.

The foot race metaphor is used advisedly. The market for low-net carbon fuels is so large that any number of players could be winners if they could produce them as cheaply as water, to borrow Jay Keasling’s words.

Jay Keasling (I wrote about him in a previous column) is the biologist who synthesized a molecule of wormwood that has come to be known commercially as artemisinin, the anti-malaria medicine.

Artemisinin is a hydrocarbon. Using essentially the same platform, Keasling and his team are trying to engineer microorganisms to create a mixture of compounds that can be made into a number of things including gasoline, jet fuel and plastics.

To make artemisinin, Keasling and his collaborators had to make 50 genetic changes to E. coli and baker’s yeast. The output of artemisinin from this effort was miniscule. To increase it a million fold, more genetic changes had to be made. The result was artemisinin at $1 per gram, cost-effective for a drug but not for a fuel. At this price, gasoline would cost $125 per liter.

At a meeting of synthetic biologists in Hong Kong in October last year, Keasling reported that he and his group were able to engineer E. coli to “more efficiently transform” starting compounds about 77-fold. He expects his company, Amyris, working with Crystalev, a Brazilian maker of ethanol, to be making renewable fuels from sugar cane by 2010.

LS9, a research company, is also engineering E. coli and other organisms to make “renewable petroleum.”

Most organisms convert excess energy into fats by a mechanism called fatty-acid biosynthesis.

Gregory Pal, a senior director of LS9, said that by making dozens of genetic transformations to microorganisms, they have “successfully produced a variety of hydrocarbons and is now focused on scaling up the technology.” LS9 expects to begin small-scale production by around the middle of 2010.

A third approach is being tried by James Liao and his associates at the University of California, Los Angeles.

They engineered E. coli to become photosynthetic to produce isobutanol, a longer-chain alcohol. Unlike ethanol, isobutanol has more energy per liter and water can be separated from it more easily. The synthetic molecule can be blended with gasoline or made into other chemical products.

The metabolic pathway that Liao is exploring converts starting materials to amino acids. He says that this pathway is adopted to handle large “flu-xes” of hydrocarbons.

Working with a bioenergy startup, Gevo, Liao says that he’s making “progress” in getting photosynthetic bacteria to make fuel simply by absorbing sunlight and carbon dioxide.

The fourth approach uses algae to produce the oils that can be converted into biodiesel.

Solarzyme, another bioenergy start-up, works with natural and engineered algal strains to produce renewable biodiesel.

But instead of growing the algae in open sunlight, it’s cultivated in enclosed steel fer-menters in which the organisms convert sugars to oils. By turning off the photosynthetic mechanism, the algae produces oils more efficiently.

Solarzyme already produces biodiesel and jet fuel in commercial quantities.

The main obstacle to the more rapid commercialization of these technologies—which are all based on genetic engineering—is the price of petroleum. At less than $40 per barrel today none of these biofuels is competitive.

As Harrison Dillon, the president of Solarzyme, said: “If you make it at the right price, you can sell as much as you can produce.”

The long-term view is more hopeful. By scaling up these technologies they can be made to produce transportation fuels that can be mixed with gasoline. But as the supply of petroleum diminishes, they can replace gasoline and diesel fuel—provided investments in them do not falter.

opinion@manilatimes.net