Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Combining Strategies Speeds the Work of Enzymes

08.05.2013
NREL research finds synergy in two approaches to breaking down cell walls of biomass
Enzymes could break down cell walls faster – leading to less expensive biofuels for transportation – if two enzyme systems are brought together in an industrial setting, new research by the Energy Department’s National Renewable Energy Laboratory suggests.

A paper on the breakthrough, “Fungal Cellulases and Complexed Cellulosomal Enzymes Exhibit Synergistic Mechanisms in Cellulose Deconstruction,” appears in the current edition of Energy and Environmental Science. Co-authors include five scientists from NREL and one from the Weizmann Institute in Israel.

The Energy Independence and Security Act of 2007 has set a goal of producing 36 billion gallons of biofuel a year in the United States by 2022, including 21 billion gallons coming from advanced biofuel production. One barrier to reaching that goal is the high cost of enzyme treatment, a crucial step in turning the biomass – poplar trees, switchgrass, corn stover, and the like – into liquid fuel.

Enzymes secreted by microorganisms naturally degrade the cell walls of plants, breaking them down so their sugars can be harvested. But plants have their own survival tricks, including mechanisms to make it harder for the enzymes to break down the cell walls. Those defenses boost the cost of producing biofuels, and have pushed researchers to try to find combinations of enzymes that can do the job faster.

NREL researchers found that two enzyme paradigms – free and complexed enzymes – use dramatically different mechanisms to degrade biomass at the nanometer scale. Further, they found that mixing the two systems enhances catalytic performance. The findings suggest that there may be an optimal strategy between the two mechanisms – one that Nature may already have worked out.

When the two enzyme systems are combined, the substrate changes in unexpected ways and that result suggests the two systems work with each other to deconstruct the cell walls more efficiently. Scientists can use this knowledge to engineer optimal enzyme formulations – fast, efficient, single-minded and hungry.

To outmaneuver the plant’s survival mechanisms, many microorganisms secrete synergistic cocktails of individual enzymes, with one or several catalytic domains per enzyme. Conversely, some bacteria synthesize large multi-enzyme complexes, called cellulosomes, which contain multiple catalytic units per complex.

While both systems use similar catalytic chemistries, the ways they degrade polysaccharides has been unclear.

NREL researchers found that the free enzymes are more active on pretreated biomass, while the cellulosomes are more active on purified cellulose. Using electron microscopes they found that free enzymes attack the plant cell wall surface by chipping and eroding, helped along by sharpening the thread-like cellulose fibers.

By contrast, the cellulosomes physically separate individual cellulose microfibrils from larger particles to enhance access to the cellulose surfaces. They assemble protein scaffolding to help get the job done.

NREL researchers observed that when the two enzyme systems are combined, the work improves dramatically, likely due to our combining enzymes that evolved naturally, and independently, to do the same job in different ways.

NREL is the U.S. Department of Energy's primary national laboratory for renewable energy and energy efficiency research and development. NREL is operated for the Energy Department by the Alliance for Sustainable Energy, LLC.

David Glickson | EurekAlert!
Further information:
http://www.nrel.gov

Further reports about: NREL cell walls electron microscope enzymes poplar tree strategies

More articles from Life Sciences:

nachricht A new molecular player involved in T cell activation
07.12.2018 | Tokyo Institute of Technology

nachricht News About a Plant Hormone
07.12.2018 | Julius-Maximilians-Universität Würzburg

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Researchers develop method to transfer entire 2D circuits to any smooth surface

What if a sensor sensing a thing could be part of the thing itself? Rice University engineers believe they have a two-dimensional solution to do just that.

Rice engineers led by materials scientists Pulickel Ajayan and Jun Lou have developed a method to make atom-flat sensors that seamlessly integrate with devices...

Im Focus: Three components on one chip

Scientists at the University of Stuttgart and the Karlsruhe Institute of Technology (KIT) succeed in important further development on the way to quantum Computers.

Quantum computers one day should be able to solve certain computing problems much faster than a classical computer. One of the most promising approaches is...

Im Focus: Substitute for rare earth metal oxides

New Project SNAPSTER: Novel luminescent materials by encapsulating phosphorescent metal clusters with organic liquid crystals

Nowadays energy conversion in lighting and optoelectronic devices requires the use of rare earth oxides.

Im Focus: A bit of a stretch... material that thickens as it's pulled

Scientists have discovered the first synthetic material that becomes thicker - at the molecular level - as it is stretched.

Researchers led by Dr Devesh Mistry from the University of Leeds discovered a new non-porous material that has unique and inherent "auxetic" stretching...

Im Focus: The force of the vacuum

Scientists from the Theory Department of the Max Planck Institute for the Structure and Dynamics of Matter (MPSD) at the Center for Free-Electron Laser Science (CFEL) in Hamburg have shown through theoretical calculations and computer simulations that the force between electrons and lattice distortions in an atomically thin two-dimensional superconductor can be controlled with virtual photons. This could aid the development of new superconductors for energy-saving devices and many other technical applications.

The vacuum is not empty. It may sound like magic to laypeople but it has occupied physicists since the birth of quantum mechanics.

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

EGU 2019 meeting: Media registration now open

06.12.2018 | Event News

Expert Panel on the Future of HPC in Engineering

03.12.2018 | Event News

Inaugural "Virtual World Tour" scheduled for december

28.11.2018 | Event News

 
Latest News

A new molecular player involved in T cell activation

07.12.2018 | Life Sciences

High-temperature electronics? That's hot

07.12.2018 | Materials Sciences

Supercomputers without waste heat

07.12.2018 | Physics and Astronomy

VideoLinks
Science & Research
Overview of more VideoLinks >>>