www.checkbiotech.org ; www.raupp.info ; www.czu.cz

Scientists are now getting their closest look yet of plant cell walls,
thanks to a new viewing method developed by the Agricultural Research
Service (ARS). It's the tough and rigid cell walls that are currently the
biggest hurdle for scientists who are trying to convert plant cellulose into
ethanol, April 2007 by Erin Peabody.

Chemist John Ralph and research associate Fachuang Lu, with ARS' U.S.
Dairy Forage Research Center in Madison, Wis., created the new cell-viewing
technique by combining a sophisticated solvent with the power of nuclear
magnetic resonance technology.

Today's ethanol is mostly derived from the starch in corn kernels. However,
vast amounts of energy remain locked up in another plant component, called
cellulose, which is found in everything from cornstalks to wood chips to
manure. That's because plants, over the course of millions of years, have
evolved elaborate cell wall structures that guard their sugar-rich cellulose
like a fortress.

The new ARS method is allowing researchers to get?for the first time?a
detailed structural view of those cell walls. This gives them unparalleled
insight when it comes to developing superior biomass crops, such as
switchgrass, with easier-to-degrade cell wall structures and traits.

The solvent gently, yet effectively, disentangles cell wall components from
one another so that they can be viewed in solution. Then, using nuclear
magnetic resonance, the scientists can obtain a detailed chemical
"fingerprint" of the major and minor structures in the walls.

Previously, to get a closer look, researchers had to spend weeks laboriously
isolating cell wall parts. The new method yields results in a matter of
days.

In addition to its potential bioenergy applications, the cell wall
fingerprinting technique should also prove helpful in solving problems
related to livestock feed inefficiency. That's because the tough and fibrous
plant cell walls that are such a headache for biofuel processors are also
wasted in undigested animal feed.

[www.ars.usda.gov]