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Although it's possible to incorporate all three genes in a single plant, says Sticklen, using three different varieties of corn, each carrying a different gene, will allow her to control the conversion of cellulose into sugars. Preliminary studies show that the enzymes are just as efficient as commercially available enzymes when combined at a ratio of 1:4:1, she says. The results suggest that mixing the three different plants using the same ratios will provide the best outcome.
"I think the strategy of compartmentalizing the enzymes in the vacuoles is terrific," says Susan Leschine, a microbiologist at the University of Massachusetts Amherst. "The question I have is, do the enzymes work under conditions that are realistic?" For instance, different microbe species secrete their own cellulases that work synergistically to chip away at the cellulose fibers. It's unclear, Leschine says, how well an enzyme taken from a microbe that lives in a hot spring will work with an enzyme drawn from a soil fungus. "These different enzymes may not be active under the same conditions," she says.
Edenspace, which is currently developing Sticklen's technology, expects to begin field trials of her genetically modified corn within the year, with the goal of commercializing the technology within the next three years, says Blaylock. The company is not alone in pursuing this strategy: Agrivida, an agricultural biotech company based in Medford, MA, is also genetically modifying corn to simplify the production of cellulosic ethanol.
"This really is a worthwhile path to follow," says Michael Ladisch, professor of agricultural and biological engineering at Purdue University, in West Lafayette, IN. "However, at the end of the day, it's more complicated than it seems." The main obstacle is finding ways to ensure that the enzymes will survive the chemical and physical pretreatment needed to remove the lignin--the tough polymer in cell walls that provides plants with strength--from the cellulose fibers, says Ladisch, who is currently on leave from Purdue to serve as the chief technical officer at Mascoma, a biofuels company based in Brighton, MA.
One solution is to engineer the plants so that they require only a mild pretreatment. For instance, Sticklen is working on reducing the amount of lignin contained in corn, as well as modifying the molecular configuration of lignin, which would make it easier to break down. Although her work is currently focused on modifying corn, Sticklen says that the technology could eventually be transferred to other crops as well, such as switchgrass.
Mascoma has announced several advances that may lead to a cheaper, more efficient process to turn biomass into ethanol.
Demand for corn-derived fuel is driving up food prices, but new technologies could help.
Frances Arnold is designing better enzymes for making biofuels from cellulose.
Morgellon's Disease Redux, anyone?
Just what we need, more FrankenCrops to pollute the real food with its pollen. Oh, that's right, there is no real food anymore, it's all been engineered by Monsanto.
Meanwhile the food riots have started . . .
I don't have a problem with biofuels, but we have GOT to stop using corn for it. There are better plants for this than corn, and the amount of corn being diverted to ethanol right now is already inflating food prices dramatically. Just imagine how bad it will be when production really gets ramped up. Any industry that relies on corn, Dairy, Beef, Poultry, and many more that would surprise you will be affected with rising prices as the supply of corn is diverted to ethanol production.
I think that since this uses what would otherwise be classified as "bagasse" rather than the food portion of the plant, it may actually help stabilize food prices and reduce the need to trailblaze new farming land from old growth forests and rainforests. Each of these plants will be used 1) as food AND 2) as energy, instead of our current "either/or" model. With more incentive and non-government price support for growing this crop, food prices will stabilize due to higher supply, and energy will diversify, which pays dividends to all of us. Why riot about that?!?!?
What I am somewhat less thrilled with is that it appears that farmers may not be able to convert this to energy on-site to run their farms as they are now by converting corn in on-site stills. I think decentralization and de-corporatization (small corps good, big corps, not so much) of energy is great and reduces costs. If this has to be shipped somewhere first, and then distributed, the returns on the energy input drop. I hope it can stay local - and this won't be put into a mega-corp that restricts its use.
Everybody wants biofuel alternatives to oil.
Congress enabled an uneconomical biofuels method via subsidies, mandates and protectionist tariffs on imports.
Now, fuel prices, food prices and taxes are higher than necessary.
Corn has gone from ~$2 a bushel to ~$6 a bushel.
Great for corn farmers / the corn "cartel".
And for corn state Senators / Reps.
Billions of tax dollars for the subsidies.
And one more special interest group lobbying Washington, to continue the status quo in their financial favor.
Corn to ethanol, while ever so well intentioned, is a stupid practice.
Leastwise, as currently practiced with the subsidies, mandates and tariffs.
Guest (ella)
This really is not an issue about frankenfoods etc. This technology really does not represent an increase of GMO acerage but a technology that will help make energy production more efficient. Syngenta is close to releasing a corn product with an amylase gene inserted into it to lessen the cost of ethanol production. This technology is doing the same thing but for cellulosic biofuel production. I am all about renewable energy sources. This is a step in the right direction.
If they're modifying it so they can use the cellulose, why bother using corn at all?
Because those who plant and process corn would profit from using the WHOLE plant. I supposer it might be possible to put the genes in other plants such as trees, grass, cactii. etc.
but then the 'green' nazis would object to any possible solution to the problem wouldn't they?
Actually you have an interesting point - why just corn? Subsidies may be a huge factor since the USDA is tightly integrated into the Agri-Biz.
As for a suggestion - make the enzymes work in simple lawn grass using a similar approach where each enzyme gets plugged in. Maybe Kentucky Blue Grass gets Enzyme A, while Fescue gets Enzyme B.
If done right, all our weekly lawn clippings become ethanol. The trick is to get a composter-widget setup in the yard so the ethanol collecting stays at home, otherwise setup some recovery program where homeowners get a credit to provide grass clippings to the local producer in exchange for a price break at the gas pump, or a write off at the end of the year for donating biomass to local businesses.
I agree. Modifying corn is not the answer. We are already seeing higher prices for corn because we are using it for non food purpose. Those people that are growing food corn, would have the knowledge on how to grow would switch to this more expensive crop. The risk of this genetically affecting our food corn is high as well.
This process seems best for switch grasses.
I had to make an account just to comment on your comments.
"To avoid the possibility of transferring the genes to other crops or wild plants, the enzymes are only produced in the plant's leaves and stems, not in its seeds, roots, or pollen,"
I believe this also means that it wont be in the corn that we eat. Its so that we can harvest the corn which is normal because they probably used a gene in the regulatory region that expresses the enzyme gene in the coding region to only be in the stems, they take the corn and instead of wasting all that extra plant that gets harvested, it can go to biofuel.
By mastering the production of biofuels from a crop that our agriculture industry is highly experienced with, we can determine best practices for other less volatile crops. Though food into fuel propositions are unfortunate and a hardship for all, they are only a transition phase in America's portable fuel economy. When corn is no longer the best option prices will stabilize. Government subsidies will no longer be politically sustainable after. Big corn simply does not have the influence that big oil does.
I've never understood this "stepping stone" or "bridge" argument. Either corn ethanol is worth doing for its own sake or it's not. It's not.
By beginning with a product you know and have completed extensive research on, you can further development very quickly. Gains can then be bridged over to other products. Starting with a product with less base knowledge amounts to reinventing the wheel.
In regards to worthiness of corn ethanol, your right, it is not a worthy long term answer. It is however a start down the road to energy independance with bio-ethanol as part of the answer for storable, portable fuel. Without corn ethanol and the infrastructure that will be developed with it we will years farther behind. We are already to far behind as it is.
Nice work doc - it's great to see some innovation coming out of Michigan for a change. The Big three have been choking for years!
Can this stuff power mass transit systems like light rail too!!!
conversion is not the big problem
There are three steps in converting sunlight into motion via plants: (1) photosynthesis to produce sugars and cellulose; (2) conversion of sugars and cellulose to a more convenient fuel; (3) burning that fuel to produce work. This work addresses Step 2, but that is not the real bottleneck. There seems to be a variety of methods to do this. Step 1 is a problem, at least on the scale of of powering 3.9 trillion US vehicle miles in 2050. Efficiencies of turning sunlight into chemical energy are only 0.38% for sugarcane, one of the best feedstocks. Only algae (which might reach 4% efficiency??) looks promising, and this needs to be compared to 30% for sunlight to electricity. Step 3 remains terribly inefficient, but requires little new technology. The inefficiency of Step 3 (a typical ICE is 21% efficient) make the problem of Step 1 all the worse. By comparison the conversion of electricity to work in an electric motor is above 90% efficient.
Corn is the top-researched plant in the world. There are more studies on corn production than almost any other. Corn is also already the top food producing plant in America. It is seemingly much easier to tailor the crop you're already producing on more than half the farms to meet a new need than to find a new crop and get farmers to accept it for each individual job.
As I read the article, I had in mind the torrents of pretreatment. How much of these enzymes would survive the very caustic step that chemically rips lignin and hemicellulosic sheaths from the cellulose, detroying 50% of the feedstock? Fortunately the article made reference to this. I personally guess that much of enzymes would not survive.
It is a good idea to grow the enzymes for free. Oddly enough, Novozyme has brought the cost of fabricated enzymes for corn stover processing down to a quite low level, but this impacts overall costs mildly. Enzymes are just one of many obstacles to cellulosic ethanol that would need to be addressed.
I'll say it again. The least expensive, least energy intensive way to use biomass that conserves the greatest amount of original energy is burning it for electricity. That includes corn kernels. 75% of the energy content of corn kernels is used when they are burned as compared to less than 50% when converted to ethanol.
I also have doubts about genetic engineering. to alter plants in such arbitrary ways could be just what opportunistic microbes need to destroy the plant.
How about a steam powered car that burns kernal corn, ie. continuously burn corn kernals to produce steam to drive a turbine or piston steam engine. Better yet, lets make the steam with a tankload of powdered coal.
I want to know what feeding the byproduct of this corn to the cattle does to the meat you eat???
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RBGoulder
1 Comment
This is scary
Genetically altered corn that needs to be separated into 3 separate groups in order to allow for the easier and cheaper breakdown of cellulose. Just how does anyone think this separation can be maintained? How will it be kept separated from the food supply and why would anyone without a very myoptic point of view risk physical destruction of one of the world's most important food supplies. This is more irrational than anything I can think of. Just because it could be done is not a reason to do it.
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camdaddy09
38 Comments
Re: This is scary
Why is there a problem she just said it couldnt be introduced into other corn. it wouldnt be in the kernels either so i dont see the harm in having a plant that can do this by itself.
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