USDA Researchers Modifying Yeast for Cellulosic Ethanol Production
29 November 2005
![]() |
L. edodes, source of the gene for xylanase |
Researchers at the USDA Agricultural Research Service have cloned a gene from the Shiitake mushroom and are using that as the mechanism for yeast or other organisms to be able to process cellulosic biomass for ethanol production.
The dominant technology for ethanol production is the fermentation of sugars from sugary plants or from plant starches converted to sugar. For cellulosic biomass to function as an ethanol feedstock, the cellulose must first be converted to fermentable sugars.
(Gasification of cellulosic biomass and then the subsequent catalytic conversion to ethanol is also a possible production route, but not one under much current consideration.)
Shiitake mushrooms (Lentinula edodes) typically grow on downed wood in the forest, converting the cellulosic material into sugars they use for food.
The Xyn11A gene carries the instructions that the mushroom uses to make the enzyme xylanase, which breaks down xylan, one of the main components of hemicellulose.
The ARS researchers transferred the Xyn11A gene into yeast. Equipped with the gene, the yeast was able to produce xylanase. In nature, the yeast normally can’t do that.
Next, the scientists will work on engineering the mushroom gene to optimize the volume and rate of production of xylanse to better determine its suitability for a commercial cellulosic ethanol process.
Resources:
“Cloning and Characterization of the Xyn11A Gene from Lentinula edodes”; Charles C. Lee, Dominic W. S. Wong and George H. Robertson; The Protein Journal; Volume 24, Number 1, January 2005, pp. 21–26; DOI: 10.1007/s10930-004-0602-0
Mushroom powered car! Now if we can GM these sweetie mushroom to feed on corn stalk or rice straw...
But this is a GM thing, careful measurement must be done before implement large scale production. It might end up a massive mega fungus outbreak and as a result, all our forests and recycled paper store are covered by mushroom.
Mushroom boom?
Posted by: rexis | 29 November 2005 at 06:32 PM
To the extreme the GM engineers might be able to create a mushroom that can convert cellulose into ethanol. The next thing to do is to collect the mushroom and squezz out the juice and then run it thru a purifier.
Posted by: rexis | 29 November 2005 at 06:35 PM
From what I am reading, there are big advances in cellulosic ethanol coming. I know some argue that bio fuels wont solve energy issues, but advances in technology certainly could change that. In terms of cullulosic ethanol I recently read an article with with this quote from Larry Walker, a professor of biological and environmental engineering at Cornell University. "There is research and development that is going to cause revolutions." He even said in 20 years maybe 50 percent of oil could be replaced. Who knows. There are such advancements occuring now, I dont think we can accuratley say what may happen.
Posted by: Cash | 30 November 2005 at 07:15 AM
They GMed the yeast, not the mushroom (the mushroom was the source of the gene that was transfered to the yeast). A yeast boom would mean a lot of alcohol all over the world. We should be able to figure out how to deal with that...
Posted by: An Engineer | 30 November 2005 at 09:05 AM
We can make all the Methanol we would ever need from growing Poplar trees and Hemp. The processing is less energy intensive than ethanol.
Believe it or not, it's easy to get a permit to grow industrial Hemp.
Posted by: Lucas | 30 November 2005 at 01:33 PM
Ethanol has more energy density than methanol and tolerates the presence of water better. An ethanol spill would quickly biodegrade. Many people already consume considerable amounts of diluted ethanol with little direct adverse effects. Consume a similar amount of methanol and death would quickly follow.
Posted by: tom deplume | 30 November 2005 at 06:42 PM
I have heard that Saccharomyces Yeast can be used to convert cellulose to fermentables and also then produce ethanol. I am wondering if anyone has had experience as i am looking at using wood waste for ethanol production? Any help would be greatly appreciated.
Cheers
M
Posted by: Mark | 10 August 2008 at 10:08 PM