Energy News  





. Iowa State Researcher Studies How Enzymes Break Down Cellulose

This illustration shows the structure of an endoglucanase enzyme. The arrows indicate straight beta-strands. You can also see the twisted alpha-helices. Peter Reilly's lab discovered the enzyme's structure by producing and crystallizing the enzyme, shooting X-rays through it and analyzing the resulting diffraction pattern. This particular enzyme breaks down cellulose by attacking bonds in the middle of sugar chains. Image provided by Peter Reilly.
by Staff Writers
Ames IO (SPX) Feb 01, 2008
Peter Reilly pointed to the framed journal covers decorating his office. Each of the six showed the swirling, twisting, complicated structure of an enzyme. Those bright and colorful illustrations are the work of his lab. And they're part of Reilly's work to understand how the structure of an enzyme influences its mechanism and its activity.

In other words, he's trying to figure out "how is it that these things work," said Reilly, a professor of chemical and biological engineering and an Anson Marston Distinguished Professor of Engineering at Iowa State University.

That's important because enzymes do a lot for all of us.

Enzymes are proteins produced by living organisms that accelerate chemical reactions. They, for example, work inside the human digestive system to break starch or protein molecules into smaller pieces that can be absorbed by the intestines. Enzymes are also used to produce bread, they're added to detergents to clean stains and they're used to treat leather. And because enzymes break down cellulose into simple sugars that can be fermented into alcohol, they're a big part of producing ethanol from cellulose.

Reilly is particularly interested in the enzymes that work on cellulose. He has a three-year, $306,000 grant from the U.S. Department of Agriculture to develop a basic understanding of how they work.

Those enzymes are known as cellulases. They're commonly produced by fungi and bacteria. And they've got a very hard job.

Cellulose is tough stuff. It's in the cell walls of plants. It's what gives a plant its structure.

"It's why trees stand up," Reilly said.

He also said, "Nature has done its best to break down cellulose."

So different enzymes have developed different ways of attacking cellulose.

One enzyme Reilly has studied and illustrated -- a cellobiohydrolase enzyme -- has an extension that works like a little plow. It rips up one cellulose chain from a cellulose crystal and feeds it into a tunnel on the main enzyme surface so that it can be chopped up.

Reilly, who can't resist a lesson in biochemistry, likes to explain how enzymes attack and break chemical bonds. He'll display diagrams on his office computer that show the bonds in cellulose molecules. He'll point out where enzymes attack some of those bonds. He'll say the chemical reactions create high-energy transition states that scientists are working hard to understand. And he'll get back to the bottom line.

"These different enzymes all do the same thing," Reilly said. "They all break down bonds between the sugars that make up cellulose."

And, he said, "For something that's not alive, enzymes are awfully sophisticated."

Reilly's students use a lot of computing power to figure out how enzymes are put together. They routinely work with CyBlue, Iowa State's supercomputer capable of 5.7 trillion calculations per second, and Lightning, an Iowa State high-performance computer capable of 1.8 trillion calculations per second.

By adding to the basic understanding of enzymes, Reilly is opening doors for new and better applications of enzymes. Better enzymes, for example, could be the key to making the production of cellulosic ethanol more efficient and more economical.

There's still a lot for chemical engineers to learn about the specialized proteins.

After all, Reilly said, "Nature has tried over and over to find ways to break down cellulose."

Community
Email This Article
Comment On This Article

Related Links
Iowa State University
Powering The World in the 21st Century at Energy-Daily.com




Tempur-Pedic Mattress Comparison

Newsletters :: SpaceDaily Express :: SpaceWar Express :: TerraDaily Express :: Energy Daily
XML Feeds :: Space News :: Earth News :: War News :: Solar Energy News
Gushan Environmental Energy Limited Opens Beijing Biodiesel Plant
New York NY (SPX) Jan 29, 2008
Gushan Environmental Energy Limited, China's largest producer of biodiesel as measured by annual production capacity, announced that its Beijing plant has commenced production, adding 50,000 tons to the company's annual biodiesel production capacity. Annual capacity of the Beijing plant is expected to increase to 100,000 tons in the fourth quarter of 2008 when additional expansion is completed.

.
Get Our Free Newsletters Via Email
  



  • Analysis: Shell to shut again in Nigeria
  • Squeezed Crystals Deliver More Volts Per Jolt
  • Analysis: One strategy for Iraq oil, power
  • Analysis: IPI faces dangers, hurdles

  • French PM to visit Japan for nuclear talks: official
  • Areva says it is ready to build 12 reactors in South Africa
  • French Niger Uranium Mines Under Direct Threat From Tuareg Nomads
  • UN team goes inside Japan's quake-hit nuclear plant

  • New Model Revises Estimates Of Terrestrial Carbon Dioxide Uptake
  • A Breathable Earth
  • Researchers Find Origin Of Breathable Atmosphere Half A Billion Years Ago
  • Study Reveals Lakes A Major Source Of Prehistoric Methane

  • FAO warns of 'alarming' loss of mangroves
  • Brazil takes action to stop alarming deforestation of Amazon
  • Forests Could Benefit When Fall Color Comes Late
  • Rwanda's Gishwati Forest Selected As Site For Historic Conservation Project

  • African Seed Collection First To Arrive In Norway On Route To Arctic Seed Vault
  • Study: African fruit is untapped resource
  • Climate change could devastate South Asia, Africa crops: study
  • Chinese dumplings trigger food scare in Japan

  • Japan's ruling coalition backs down on fuel tax -- for now
  • Global automakers output hit by China snow storms
  • Japan's TEPCO to test park and charge system
  • China's auto production to exceed 10 mln in 2008: official

  • China to build 97 new airports by 2020
  • EADS offers to build military, civilian aircraft in US
  • Qatar Airways looking to natural gas fuel
  • Purdue Wind Tunnel Key For Hypersonic Vehicles And Future Space Planes

  • Nuclear Power In Space - Part 2
  • Nuclear Power In Space
  • Outside View: Nuclear future in space

  • The content herein, unless otherwise known to be public domain, are Copyright 1995-2007 - SpaceDaily.AFP and UPI Wire Stories are copyright Agence France-Presse and United Press International. ESA Portal Reports are copyright European Space Agency. All NASA sourced material is public domain. Additional copyrights may apply in whole or part to other bona fide parties. Advertising does not imply endorsement,agreement or approval of any opinions, statements or information provided by SpaceDaily on any Web page published or hosted by SpaceDaily. Privacy Statement