CleanTechnica is the #1 cleantech-focused
website
 in the world. Subscribe today!


Biofuels DOE scientists make gasoline, diesel and jet biofuel with e. coli bacteria and switchgrass

Published on November 29th, 2011 | by Tina Casey

4

E. Coli Bacteria: What Doesn’t Kill Us, Makes Us Biofuel

Share on Google+Share on RedditShare on StumbleUponTweet about this on TwitterShare on LinkedInShare on FacebookPin on PinterestDigg thisShare on TumblrBuffer this pageEmail this to someone

November 29th, 2011 by  

DOE scientists make gasoline, diesel and jet biofuel with e. coli bacteria and switchgrassThat notorious killer bacteria e. coli is making renewable biofuel hand over fist for researchers at the U.S. Department of Energy. Scientists based in DOE’s Joint BioEnergy Institute have tweaked a strain of the bug to munch on tough-to-digest switchgrass like it’s sugar candy, and the result is a process that yields not one biofuel but three: renewable gasoline, diesel and jet biofuel. Hey, it’s like the Ginsu Knife of biofuels, right down to the low-low price.

More Biofuels, Less Money

Cost competitiveness really is the bottom line for biofuels, and that’s where E. coli (short for of  Escherichia coli) comes in. According to Jay Keasling, the CEO of the BioEnergy Institute, the new strain of bacteria will cut costs by eliminating expensive steps that are otherwise needed to break down the tough cell walls of woody plants like switchgrass, to get at the goodies inside. In a press statement, Keasling described the e. coli-fueled process as a “one pot operation.”

E. Coli and Biofuel Crops

If you recall the corn ethanol craze that marked the end of the previous president’s administration (okay, so George W. Bush – hey, whatever happened to that guy?), you may also recall that U.S. biofuel policy at the time helped to spur a global food crisis by diverting too much corn to refineries. President Obama’s administration has focused on a biofuel policy that emphasizes non-food biomass, which places a heavy load on switchgrass and other weedy or woody grasses and plants. The downside has been the extra expense of breaking down these tougher plants, and the new strain of E. coli offers a way out.

E. Coli Biofuels – But Wait, There’s More!

The new process packs in another benefit compared to corn-based biofuel refining. Corn starch yields ethanol, which don’t replace any commonly used transportation fuel entirely. That’s why you can’t get pure ethanol when you go to the gas station, only ethanol blends. The new strain of E. coli produces biofuel substitutes and precursor molecules that can produce gasoline as well as diesel and jet biofuel on a gallon-for-gallon basis.

How Do They Do It?

Writer Lynn Yarris at the Lawrence Berkeley National Laboratory (a partner in the BioEnergy Insititute) explains that conventional strains of E. coli bacteria can’t grow on switchgrass, so the research team engineered strains that express an enzyme enabling them to get nourishment from cellulose (the tough material in plant cell walls) and hemicelllose (a weaker substance also present in cell walls). With additional adjustments to the bacteria’s metabolic pathways, the team was able to produce the three biofuels. There is also one additional secret: the switchgrass was pretreated in a bath of molten salt to soften it up.

But Wait, There’s Green Jobs

A good chunk of the President’s biofuel policy is geared toward creating permanent green jobs in rural areas, helping small, far-flung communities achieve economic sustainability and civic stability. That’s a far cry from the temporary housing camps sprouting in the western U.S. where oil fields are booming. The oil money, apparently, is good for now but when those wells tap out, there goes the neighborhood.

Image: E.coli bacteria for biofuel courtesy of Lawrence Berkeley National Laboratory.

Follow on Twitter: @TinaMCasey

Keep up to date with all the hottest cleantech news by subscribing to our (free) cleantech newsletter, or keep an eye on sector-specific news by getting our (also free) solar energy newsletter, electric vehicle newsletter, or wind energy newsletter.

Share on Google+Share on RedditShare on StumbleUponTweet about this on TwitterShare on LinkedInShare on FacebookPin on PinterestDigg thisShare on TumblrBuffer this pageEmail this to someone

Tags: , , , , ,


About the Author

Tina Casey specializes in military and corporate sustainability, advanced technology, emerging materials, biofuels, and water and wastewater issues. Tina’s articles are reposted frequently on Reuters, Scientific American, and many other sites. Views expressed are her own. Follow her on Twitter @TinaMCasey and Google+.



  • Pingback: Cone Snails (Genus: Conus) | Species Project

  • Pingback: Escherichia coli (E. coli) | Species Project

  • Boxer750il

    Too bad Tina can’t keep her political stance quiet about an interesting breakthrough. It was Bush who talked about biofuels from switch grass in his State of the Union Address in 2006.

    Several items in this blog is wrong. Not all E coli are “killer” bacteria. Many are benign gut organisms but a few are pathogenic such as the 0157:H7 known for Hemolytic Uremic Syndrome and 0104:H4 (enterohemmorhagic strain leading to the HUS)in Germany. E. coli is a marker for aquatic environmental marker for sewage contamination.

  • Anonymous

    Switchgrass is an excellent plant for biofuel.

    It has low water and fertilizer requirements. It’s a perennial and only requires a bit of fertilizer while getting established. It’s one of the grasses of the Great Plains so it is well adapted to the US climate.

    It has an extensive root system and fixes significant carbon underground with its root system, so it helps to pull carbon out of the atmosphere.

    It will grow in very marginal land, such as ‘burned out’ cotton fields and improves the soil to that later the soil can be returned to food/fiber use.

    It’s probably going to grow in areas that are ‘on their way out’ as climate change moves land from agricultural to desert. Perhaps the last commercial use for transitional land.

    It can be grown in swaths between other crop fields as a soil/fertilizer/water runoff trap.

    It can be cut much like cutting hay, dried and transported easily.

    There’s a new ‘geo-engineered’ variety which remains in a juvenile, pre-seed state and produces more sugar.

    Lots to love about switchgrass.

Back to Top ↑