Shiitake mushroom. Click
the image for more information about it.
Shiitake Mushrooms' Secret May Benefit
Earth-Friendly Fuels By
Marcia Wood November 29, 2005
Fallen logs on the forest floor make a perfect home for Shiitake
mushrooms. These fungi--sold as a delicacy in the produce section of your local
supermarket--thrive on the downed wood, turning it into sugars that they use
Now, Agricultural Research
Service scientists in California are looking at bringing the gourmet
mushrooms' mostly unstudied talent indoors. And, as a first step towards doing
that, they've found and copied a Shiitake gene that's key to the mushroom's
ability to dissolve wood.
Called Xyn11A, the gene carries the instructions that the
mushroom uses to make an enzyme known as xylanase. The researchers want to see
if a ramped-up version of the gene could be put to work digesting rice hulls or
other harvest leftovers.
If enzymes can do that quickly and efficiently in huge vats, or
fermenters, at biorefineries, they could help make ethanol and other products a
practical alternative to todays petroleum-based fuels, for example.
Thats according to
C. Lee, an ARS research chemist.
With colleagues, Lee isolated and tested the Xyn11A gene, the
first of its kind to be discovered in Shiitake mushrooms, Lentinula
Lee did the work with research chemist
W.S. Wong and chemical engineer
H. Robertson. The scientists are based at the ARS
Regional Research Center in Albany, Calif.
In laboratory experiments, they transferred the Xyn11A gene
into yeast. Equipped with the gene, the yeast was able to produce xylanase. In
nature, the yeast normally cant do that.
The researchers described their work earlier this year in Protein Journal.
Next, the scientists will work on engineering the mushroom gene so
that it enables yeast or some other organism to produce greater amounts of the
xylanase enzyme in less time. Gains in efficiency could help make biorefining
of plant-based fuels and other products a practical alternative to petroleum
ARS is the U.S. Department of
Agricultures chief scientific research agency.