By Susan Kinzie and David A. Fahrenthold
Washington Post Staff Writers
Monday, March 10, 2008
A strain of bacteria accidentally found in the Chesapeake Bay more than 20 years ago -- a bug that decomposes everything from algae to newspapers to crab shells -- could help produce cheaper fuel, according to scientists at the University of Maryland.
Gov. Martin O'Malley (D) will tout the work of professors Steven Hutcheson and Ronald Weiner on campus today in announcing that Zymetis, a U-Md. spinoff company, will use the organism to generate ethanol.
The hope is that the bacterium can be used to produce ethanol more efficiently and inexpensively and in effect recycle junk into energy. The bacterium, which is very difficult to find in nature but easily reproduced in the lab, has turned bench scientists into entrepreneurs.
It's a remarkable bug, Hutcheson said. "There's nothing out there that compares to it."
With environmental, economic and geopolitical reasons to find alternatives to gasoline, there's a sense of urgency behind scientists' drive to make cheap fuels out of such plants as grasses and wood. Other scientists said that the U-Md. research might mark a significant step in that struggle but that it was difficult to judge the discovery in detail without more information.
Ethanol is, essentially, fermented plant matter: Parts of the plants are broken down into sugar, which is converted into a kind of alcohol that is usable as fuel. For now, most U.S. ethanol is made from corn, but scientists want a source that isn't also sought after for food.
They are now seeking to make fuel out of such things as wood chips, cornstalks and a prairie plant called switch grass. But the fuel in these plants is locked up chemically in such substances as cellulose, which nature has engineered not to break down, unlike the starches in grains.
"That's the reason why you eat bread but you build houses out of wood," said Philip Pienkos of the U.S. Department of Energy's National Renewable Energy Laboratory.
That's where this bug comes in. The bacterium Saccarophagus degradans, or sugar eater, can create a mix of enzymes that degrades plant matter. It has the largest known concentration of enzymes that eat carbohydrates, Hutcheson said.
"It basically is the ultimate bottom feeder," said Jonathan Dinman, an associate professor of cell biology and molecular genetics at U-Md. "It eats what nobody else will eat -- cornstalks, leftover chaff from hay or whatever -- and can turn that into ethanol."
Some researchers now use a pretreatment that softens the plants, then another treatment to turn cellulose into sugar, then a fermentation that turns the sugar into alcohol. Several scientists said that if the U-Md. research could make this process faster and more efficient, it could produce serious savings.
"If this guy's got the answer to it, heck, yeah," it would be the product of the year, said Mark E. Downing, of the Department of Energy's Oak Ridge National Laboratory in Oak Ridge, Tenn.
But Bruce E. Dale, a professor of chemical engineering at Michigan State University, said he wondered how much difference one bacterium could make. "There's never been, to my knowledge, a microorganism that, without help [from scientists] . . . can break down cell walls completely and rapidly," Dale said.
If such an organism existed, he said, plants would probably have found a way to defend themselves. "If there's organisms out in the world doing that," they would be "turning all the trees into puddles."
The bacterium isn't a parasite or a plant pathogen, Weiner said, adding that research has shown it attacks only dead organic matter. It was found in the mid-1980s by scientists at George Mason University looking for the organism killing wild grass.
In the lab, most people just call it 240 -- not for the Maryland area code, but because it was the 40th sample isolated on a researcher's second day in the salt marsh.
The bug interested a scientist at George Mason, and at a conference in the late 1980s, Weiner, who happened to sit next to him, was invited to collaborate.
The other scientist soon moved on, but Weiner was hooked. "It was unique. It was the first marine bacterium shown to degrade woody material. . . . How does CO2. . . go from a complex carbohydrate in the ocean to atmospheric CO2? . . . It was a whole missing link. This organism was absolutely the first and remains the paradigm for how that occurs."
It was obvious, too, that it had tremendous ability to degrade all kinds of complex carbohydrates. "I started off fascinated with it," Weiner said, "and the more we studied it, the more fascinated we got."
In about 2000, Hutcheson joined the department and began working on 240. He drove to the salt marsh, a stretch of ecological preserve in Mathews County, Va., to try to isolate more samples of the bacterium.
In more than a dozen tries, the researchers haven't been able to.
With the help of the Energy Department, they got its genome sequenced. Weiner worked almost straight through a few nights because he was so excited when the data came back. "That was a breakthrough," said Larry Taylor, then a doctoral student in the lab and now at the National Renewable Energy Laboratory.
A few years ago, Weiner decided to step away from the theoretical and try an informal experiment: He snipped branches off a bunch of his wife's houseplants and put the clusters of leaves into glass flasks with 240. In other flasks, he combined 240 with newspaper or magazine pages. Then he had a group of 10 control flasks with just the bacteria.
He came back to the lab after the holidays -- a week, maybe 10 days later, and burst out, "Who the devil took our flasks?"
He looked again and counted. There were 20 there, but they all looked empty. "The plant matter had all disappeared," he said. "I never anticipated the organism would be that efficient. That's when we knew the organism not only did things in microculture but had the potential to be useful on a grander scale."
They had always known the research could one day be helpful for making ethanol, but the more they found out, Hutcheson said, the more possible -- and compelling -- the practical applications began to seem. And when he watched President Bush talk about alternative fuels in the State of the Union speech a couple of years ago, he almost fell out of his seat, he recalled. He began to put together the company through the Technology Advancement Program at U-Md.
About a year ago, Dinman joined them to help bump up the fuel yields they get from sugars using genetically engineered yeast. "Yeast has been used to make ethanol since the first caveman got a buzz off of fermenting berries," he said.
There are still a lot of hurdles, Dinman said. There is plenty of competition, too. Weiner said the big question is whether it can be cost-competitive; Hutcheson said they reduced production costs 20-fold in less than a year.
Hutcheson hopes to have the pilot plant running this summer. And when he gets a chance, he'll go back to the marsh. He's still looking for 240.
View all comments that have been posted about this article.