Mar 21 2011
Fuel From Bacteria
We are used to thinking of bacteria as germs – something to be shunned. In fact, the vast majority of bacteria species are indifferent to humans – they are neither helpful nor harmful. A small minority of species are pathogenic, capable of infecting humans and causing harm. And a small number of species live symbiotically with humans. We all carry an ecosystem of about 100 bacteria species in and on us.
With genetic engineering technology we have also created a fourth category of bacteria – those that can be used as microscopic factories. For years we have been using bacteria to cheaply manufacture drugs and other compounds. Just insert the gene for human insulin in the right place, and the little buggers start cranking it out.
Researchers are exploring the use of genetically engineered bacteria for other uses as well. For example, bacteria have been shown to secrete nanotubes, and can potentially be used for microelectronics.
But the potential application that seems to be getting the most press attention is making biofuels from bacteria. Bacteria can function to digest a biofuel crop, like switch grass, typically breaking down the cellulose so that it can be processed into ethanol. But a potentially superior approach would be to have bacteria produce fuel directly. Because the direct method avoids potentially expensive steps, it is likely to be more cost-effective, which is critical for the adoption of any alternative fuel.
There are frequent news items claiming breakthroughs in this technology, but two I want to mention specifically. Here’s the first.
The findings, reported online in the journal Applied and Environmental Microbiology, mark an important advance in the production of normal butanol, or n-butanol, a four-carbon chain alcohol that has been shown to work well with existing energy infrastructure, including in vehicles designed for gasoline, without modifications that would be required with other biofuels.
They achieved this with a modified version of the common bacterium, E. coli.
A second team announced a few weeks ago that they modified a cyanobacterium to produce diesel fuel or ethanol.
These are both exciting breakthroughs – bacteria essentially can thrive on waste and sunshine and produce biofuel. They fix carbon from the atmosphere, which then gets released upon burning, so such biofuels would be carbon neutral (the same is not true of some crop-based biofuels where the crops are fertilized with petrochemical-based fertilizer).
I have actually been reading about claimed breakthroughs with bacteria to fuel technology for a few years. This is one of those future technology news items that is hard to know if it will pan out, and how soon. Is this a hand-held computer or jetpack? It seems that there are non-trivial technical hurdles to overcome, mostly involved with scaling up the production. It’s one thing to make diesel fuel in some small test containers, another to run a massive factory generating millions of gallons. If the process can’t scale up, we won’t ever be pumping it into our cars.
What is clear is that engineered bacteria are already a proven technology, and I think it’s probable that they will be increasingly used in the future. Beyond being microfactories, researchers are exploring the use of engineered bacteria to augment the bacterial flora of our bodies, with potential health benefits.
But predicting any particular application is difficult. I think the chances are good for biofuel from bacteria, and I certainly hope this technology pans out. But it remains to be seen.
26 Responses to “Fuel From Bacteria”
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Interesting, except I am reading this on my pocket computer…
Dave – yes, that was my point. We have pocket computers, we don’t have jetpacks – so which one is fuel from bacteria going to be?
Since the bacteria eats CO2 (and sun and water) and makes fuel, on the surface it seems that this could be turned into a closed-CO2-cycle “battery” or “engine”, recharged by sunlight. Given the potential inefficiencies of collecting and distributing truckloads of fuel from a bacteria “farm”, perhaps this technology could turn into something that provides more local energy production.
James Liao does some nice work. This is another baby step in the whole scheme of things which is reflected in the fact that this paper was published in AEM.
Also keep an eye on Jay Keasling.
You wrote: “We all carry an ecosystem of about 100 bacteria species in and on us.”
I have always wondered at this number. It is often quoted how many trillions of bacteria cells we have as cohabitants. I always expected the number of species to be in the thousands.
Do you have some more links to info about the 100 species?
How many species are normally pathogens?
(Apologies in advance for the somewhat off-topic comment.)
I know I’m just speculating here, but wouldn’t it be great to have a composter running in your backyard which produces fuel for our cars from food and garden waste? That would really make our society much less vulnerable to infrastructure failures (i.e. massive electricity blackouts that strand tens or hundreds of millions of people who can’t get gas for their cars) and stick it to the energy companies who are making huge profits, while driving up prices.
Of course, this technology would probably only be possible on a larger, industrial scale because I doubt there’s enough energy in household waste to meet our daily need for gasoline. It’s cool to imagine, though.
Assuming the bacteria is using waste to produce the biofuel this is a marvelous idea. If, as is the current method, they are using crops, this doesn’t have long term good value.
We need to feed the world and we are soon going to be facing some serious problems in that arena. Imagine the competition for land use between fuel producers and food producers.
Americans have so much land, and we even pay our farmers not to farm, that we forget – land is a limited resource. Farmable land in particular.
Just putting some questions out there…
Is this the kind of thing that would require political will to accomplish, or would smaller-scale collaborations suffice?
At some point, to make this feasible, biologists of many different disciplines have to talk to the chemists and engineers to get a working system going for production and eventual use.
Who does this? A University? Private company? Government issued cooperative grants?
I feel it takes some pushing beyond the individual lab that makes the “breakthrough” to get this beyond just an interesting proof of concept.
I was reminded just this weekend about this odd notion I read about years ago. Some person believes that oil is being continually produced by bacteria beneath the ground and published a scientific paper on the subject.
I don’t know if that paper addressed the question of how much and how quickly. That is. “Fine, the oil isn’t as old or made in the way we thought, but if we continue to use it at the current rate we are hosed anyway.”
At 15,000 gallons per acre, the number of square miles that it would take to produce the current oil use in the US would be around 31,300 square miles (about the area of Maine).
Assuming the actual is less than that (and some infrastructure is required) the whole operation could probably fit in Oklahoma.
That would make for a very strange drive.
Enzo-
The one group claims to be able to produce oil at $30 a barrel. Current prices are round $100.
If the thirty is correct, then money to make this happen will be forth coming from private investors- no need for any other funding.
But…don’t the bacteria get to have a say in all of this?
http://star.tau.ac.il/~eshel/papers/Trends-published.pdf
I don’t think you will get 15,000 gallons per year per acre. These things are always over-egged. You should probably half that at least.
That being said, i’m not quite sure why removing excess water from the fuel would be a show stopper. The processing of the poor quality oils we are now reaching is probably far more costly and complex.
eiskrystal: “That being said, i’m not quite sure why removing excess water from the fuel would be a show stopper. The processing of the poor quality oils we are now reaching is probably far more costly and complex.”
It sounds as if it should be easy, but dewatering fuel is very energy intensive, more so than the relativly simple ‘cracking’ process used to refine crude oils. The organic-waste fuel-plant of the future would probably have to sit on top of a hydrothermal power plant (or some such) to provide it with the extra juice.
Also, pretty much all the end products of cracking are useful in some way, but when you dewater synthetic fuel you end up with a little bit of fuel and lots and lots of dirty water that no-one wants.
BillyJoe7: ” But…don’t the bacteria get to have a say in all of this?” http://star.tau.ac.il/~eshel/papers/Trends-published.pdf
I suppose there’s no real reason why they shouldn’t, but how the heck do two Israeli physicists and an engineer get around to writing a paper on bacteria? Talk about going off on a tangent.
I found the following quote intriguing: “bacteria can lead rich social lives.”
Might this include barn dances?
SteveA,
“how the heck do two Israeli physicists and an engineer get around to writing a paper on bacteria?”
And evolution – they’re overthrowing the paradigm no less!
“Might this include barn dances?”
Apparently only those that are observed by special people like Shapiro
…oh, and it is one of cwfong’s favourite links
Warning: Not recommended for the ignorati, who may suffer from an unusual degree of dissonance when accessing these sites without their rationalization tutors present.
http://www.molbio.princeton.edu/index.php?option=content&task=view&id=27
http://shapiro.bsd.uchicago.edu/
http://www.geo.umass.edu/faculty/margulis/
http://www.tau.ac.il/~cohn/staff/eva-jablonka.htm
http://www.project-syndicate.org/contributor/1522
Dr.Novella, go ahead and remove that last post entirely. It was to be my last post here in any case.
Hydrocarbons are insoluble in water and are lower density than water, so they can be separated from water simply by letting an oil-water mixture settle. There can be oxidized oil compounds (fatty acids) that behave like soaps and emulsify the oil and water, but those emulsions can be broken.
Butanol is difficult to separate from water. It is very soluble, and phase separates out at ~10% forming a ~80% butanol phase. That phase probably disrupts any bacterial membrane, so the butanol has to be taken out before it gets that high. Distillation is not feasible because it takes so much energy. You have to vaporize the water out of the butanol. It takes more than the fuel value of the butanol to recover it by distillation.
If eiskrystal is right and we need to halve the projected output, then we would have to double the land area for this project.
That means we are talking @62,000 square miles- about the size of Missouri.
People would try to make these bacterias produce as much as possible- that is they would try to create the perfect conditions for them to operate. An area the size of Missouri- perfect conditions–hmmm
Sounds like those bacteria might be smarter than we know after all…
Personally I can’t wait for the anti-bac crowd to start complaining of extra colds and flu near processing plants.
Which brings up an important point, how do you stop the bacteria from evolving….
“how do you stop the bacteria from evolving….”
According to that paper I linked to, bacteria create their own favourable mutations (I kid you not) and thereby self-evolve, so pretty soon they’ll be throwing bombs at us.
The human body contains 100 trillion cells and about 1000 trillion bacteria, so look out!
cwfong,
“Dr.Novella, go ahead and remove that last post entirely. It was to be my last post here in any case.”
artlessDodge -> bungle -> cwrong -> ?
He will sneak back quietly, at first just barely recognisable but, after a few days, he won’t be able to help kimself and the chest beating and condescension will begin anew.
For some reason this post was deleted and then later undeleted.
cwfongon 22 Mar 2011 at 5:07 pm
Warning: Not recommended for the ignorati, who may suffer from an unusual degree of dissonance when accessing these sites without their rationalization tutors present.
Please delete it permanently.
cwrong,
“Warning: Not recommended for the ignorati, who may suffer from an unusual degree of dissonance when accessing these sites without their rationalization tutors present.”
I’m looking forward to mangling your next incarnation.
Cellulase in a practical industrial form would be a great solution to energy flux, there is a lot of cellulose all around us…..but what form does the cellulose need to be in and what are the waste issues? What land use changes will we need? Will vast quantities of ethanol have social consequences?
I wonder what the unknown downsides will be?
I would love a digester in my shed that I back the car up to each week, and use the dry waste as fertiliser…But the sixties SF dreams are rarely coming without strings attached.
(Thus of course cyberpunk.)
The petrol stock of the world is about to finish.I am not sure that how much of petrol we can save for our next generation.So, we have to think for any alternative source to produce petrol.Its a very good news that we can produce petrol from bacteria.Again its a great news that we have 100 bacteria of this kind.Looking forward to get a successful result.