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 Map of the Cell’s Power Station
18.08.2017 | Albert-Ludwigs-Universität Freiburg im Breisgau

nachricht On the way to developing a new active ingredient against chronic infections
18.08.2017 | Deutsches Zentrum für Infektionsforschung

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Fizzy soda water could be key to clean manufacture of flat wonder material: Graphene

Whether you call it effervescent, fizzy, or sparkling, carbonated water is making a comeback as a beverage. Aside from quenching thirst, researchers at the University of Illinois at Urbana-Champaign have discovered a new use for these "bubbly" concoctions that will have major impact on the manufacturer of the world's thinnest, flattest, and one most useful materials -- graphene.

As graphene's popularity grows as an advanced "wonder" material, the speed and quality at which it can be manufactured will be paramount. With that in mind,...

Im Focus: Exotic quantum states made from light: Physicists create optical “wells” for a super-photon

Physicists at the University of Bonn have managed to create optical hollows and more complex patterns into which the light of a Bose-Einstein condensate flows. The creation of such highly low-loss structures for light is a prerequisite for complex light circuits, such as for quantum information processing for a new generation of computers. The researchers are now presenting their results in the journal Nature Photonics.

Light particles (photons) occur as tiny, indivisible portions. Many thousands of these light portions can be merged to form a single super-photon if they are...

Im Focus: Circular RNA linked to brain function

For the first time, scientists have shown that circular RNA is linked to brain function. When a RNA molecule called Cdr1as was deleted from the genome of mice, the animals had problems filtering out unnecessary information – like patients suffering from neuropsychiatric disorders.

While hundreds of circular RNAs (circRNAs) are abundant in mammalian brains, one big question has remained unanswered: What are they actually good for? In the...

Im Focus: RAVAN CubeSat measures Earth's outgoing energy

An experimental small satellite has successfully collected and delivered data on a key measurement for predicting changes in Earth's climate.

The Radiometer Assessment using Vertically Aligned Nanotubes (RAVAN) CubeSat was launched into low-Earth orbit on Nov. 11, 2016, in order to test new...

Im Focus: Scientists shine new light on the “other high temperature superconductor”

A study led by scientists of the Max Planck Institute for the Structure and Dynamics of Matter (MPSD) at the Center for Free-Electron Laser Science in Hamburg presents evidence of the coexistence of superconductivity and “charge-density-waves” in compounds of the poorly-studied family of bismuthates. This observation opens up new perspectives for a deeper understanding of the phenomenon of high-temperature superconductivity, a topic which is at the core of condensed matter research since more than 30 years. The paper by Nicoletti et al has been published in the PNAS.

Since the beginning of the 20th century, superconductivity had been observed in some metals at temperatures only a few degrees above the absolute zero (minus...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Call for Papers – ICNFT 2018, 5th International Conference on New Forming Technology

16.08.2017 | Event News

Sustainability is the business model of tomorrow

04.08.2017 | Event News

Clash of Realities 2017: Registration now open. International Conference at TH Köln

26.07.2017 | Event News

 
Latest News

A Map of the Cell’s Power Station

18.08.2017 | Life Sciences

Engineering team images tiny quasicrystals as they form

18.08.2017 | Physics and Astronomy

Researchers printed graphene-like materials with inkjet

18.08.2017 | Materials Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>