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modified yeast is feasting on the juice of the sugarcane that is so
abundant in this country. "Inside is cutting-edge American technol-
ogy applied to the competitive advantage of Brazil," he explains.
For the last two years, Collier's responsibilities have included
shipping drums of frozen Brazilian sugarcane juice to Amyris's
California laboratory, some 10,000 kilometers away. There, scien-
tists have been genetically rewiring ordinary yeast cells to digest
caldo de cana, as the juice is called, and turn it into farnesene, a
fragrant oil that Amyris has shown can be converted into diesel
fuel. In the fast-moving field of synthetic biology---a discipline that
looks to rewrite the DNA of microörganisms as if it were computer
code---the California laboratories of Amyris are considered state
of the art. Researchers create and test tens of thousands of engi-
neered yeast strains each week. The company employs nearly as
many PhD yeast geneticists as all the universities in Brazil.
But Brazil o ers Amyris one critical advantage over the United
States: the economic conditions there lend themselves to exploit-
ing the technology commercially. Brazil is the world's most e -
cient producer of sugar. Huge mounds of it pile up at the country's
420 sugarcane refineries. With its tropical weather and aggressive
business culture, the country dominates the global sugar trade.
And enormous supplies of inexpensive sugar are the key to mak-
ing Amyris's technology practical.
"The reason to go to Brazil was pretty clear; it's the cheapest, most
readily available source of sugar to power the technology platform,"
says Keasling, a professor of biochemical engineering at the Uni-
versity of California, Berkeley, who also heads the Joint BioEnergy
Institute, a $135 million e ort funded by the U.S. Department of
Energy to extract sugars from wood chips, grass, and other inex-
pensive plant matter. In 10 to 15 years, its work could make sugar
molecules as cheap to obtain in the U.S. as they currently are in
Brazil. For now, though, the U.S. biofuels industry continues to
make ethanol by fermenting the glucose in corn kernels. And corn
is a relatively costly source of sugar, as the American ethanol indus-
try has discovered to its distress. Despite taxpayer subsidies, U.S.
manufacturers have not been able to turn consistent profits.
The story is di erent in Brazil, where sugarcane mills have been
turning out inexpensive ethanol since the government launched a
push for fuel independence in the 1970s. The country's automobile
fleet now consumes more ethanol than gasoline. Nearly 90 percent
of cars manufactured in Brazil can run on the biofuel. The indus-
try has realized that "geography is destiny," says Mark Bunger,
research director at Lux Research, a New York firm that studies
the commercialization of emerging technologies. In Bunger's
view, only a few places on the planet have the rain, sun, and land
mass needed to make biofuels at the scale and price that can have
a real impact. "The understanding that we are coming to is that
it's never going to happen in some places," he says, "and Brazil is
the first place where the economics make sense."
Amyris reached a similar conclusion about three years ago---
hence its identical fermentation labs in Emeryville and Brazil.
Scientists in California tinker with yeast to make it convert sugar
to farnesene more quickly; then the bugs are airmailed south for
testing under tropical conditions. This year, Amyris plans to begin
construction of a towering fermentation complex in the Brazil-
ian state of Goiás. When it's done, it should be able to produce 100
million liters of green diesel fuel every year.
Like ethanol, Amyris's fuel will be made by fermenting sugar.
But company scientists have redesigned yeast so that the microbes
process it into combustible hydrocarbons instead of alcohol. That
means the competition for its green fuel is not ethanol but diesel
made from petroleum and also biodiesels made from vegetable
oil or animal fat. Amyris says its fuel has a number of advantages
over both. Unlike fossil fuels, it is made from a renewable source.
It also contributes less greenhouse gas to the atmosphere: the com-
pany calculates that its Brazilian-made diesel will emit about 80
percent less greenhouse gas than conventional diesel. And com-
pared with other biodiesels, its sugar-based fuel will be cheaper
to make and will enable engines that use it to run better. Amyris's
CEO, a former oil executive named John Melo, has been negoti-
ating with companies that are looking for a green fuel, including
Federal Express, Virgin Atlantic, and General Electric.
For many synthetic biologists, diesel is just the beginning. They
believe that in principle, they can create microörganisms to pro-
duce replacements for any petroleum product. But there are huge
risks. Amyris's yeast strains have proved unexpectedly vulner-
able. And as with other biotechnology processes that depend
on live microörganisms, no one can say if green diesel produc-
tion can be scaled up economically from the 1,000-liter batches
produced today. "All the forecasts are based on e ciencies of
scale for processes that have never been run at those scales," says
Noubar Afeyan, CEO of Flagship Ventures in Cambridge, MA,
and a cofounder of LS9, a competing synthetic-biology startup.
A major challenge is that it "takes hundreds of millions of dollars
to prove it, even at medium scale."
Nine years ago, Amyris's technology was still a bench project
in Keasling's Berkeley laboratory. Researchers had been looking
at ways to coax microörganisms to produce commercially useful
For many synthetic
biologists, diesel is just
the beginning. They believe
that in principle, they can
create microörganisms to
produce replacements for
any petroleum product.
But there are huge risks.
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