Scientists create renewable fossil fuel alternative using bacteria

Sep 02, 2014
Escherichia coli. Credit: Rocky Mountain Laboratories, NIAID, NIH

The development is a step towards commercial production of a source of fuel that could one day provide an alternative to fossil fuels.

Propane is an appealing source of cleaner fuel because it has an existing global market. It is already produced as a by-product during natural gas processing and petroleum refining, but both are finite resources. In its current form it makes up the bulk of LPG (liquid petroleum gas), which is used in many applications, from central heating to camping stoves and conventional motor vehicles.

In a new study, the team of scientists from Imperial College London and the University of Turku in Finland used Escherichia coli to interrupt the that turns into cell membranes. The researchers used enzymes to channel the fatty acids along a different biological pathway, so that the bacteria made engine-ready renewable propane instead of cell membranes.

Their ultimate goal is to insert this engineered system into photosynthetic bacteria, so as to one day directly convert solar energy into chemical fuel.

The results of the study are published in the journal Nature Communications.

Dr Patrik Jones, from the Department of Life Sciences at Imperial College London said: "Although this research is at a very , our proof of concept study provides a method for renewable production of a fuel that previously was only accessible from fossil reserves. Although we have only produced tiny amounts so far, the fuel we have produced is ready to be used in an engine straight away. This opens up possibilities for future sustainable production of renewable fuels that at first could complement, and thereafter replace like diesel, petrol, natural gas and jet fuel."

The scientists chose to target propane because it can easily escape the cell as a gas, yet requires little energy to transform from its natural gaseous state into a liquid that is easy to transport, store and use.

"Fossil fuels are a finite resource and as our population continues to grow we are going to have to come up with new ways to meet increasing energy demands. It is a substantial challenge, however, to develop a renewable process that is low-cost and economically sustainable. At the moment algae can be used to make biodiesel, but it is not commercially viable as harvesting and processing requires a lot of energy and money. So we chose propane because it can be separated from the natural process with minimal energy and it will be compatible with the existing infrastructure for easy use" added Dr Jones.

Using E. coli as a host organism, the scientists interrupted the biological process that turns fatty acids into cell membranes. By stopping this process at an early stage they could remove butyric acid, a nasty smelling compound that is an essential precursor for propane production.

To interrupt the process, the researchers discovered a new variant of an enzyme called thioesterase which specifically targets fatty acids and releases them from the natural process. They then used a second bacterial enzyme, called CAR, to convert butyric acid into butyraldehyde. Finally, they added a recently discovered enzyme called aldehyde-deformylating oxygenase (ADO), which is known to naturally create hydrocarbons, in order to form propane.

Previous attempts to use the ADO enzyme have proved disappointing as scientists have been unable to harness the natural power of the enzyme to create cleaner fuel. But the scientists at Imperial discovered that by stimulating ADO with electrons they were able to substantially enhance the catalytic capability of the enzyme, and ultimately produce propane.

The level of propane that the scientists produced is currently one thousand times less than what would be needed to turn it into a commercial product, so they are now working on refining their newly designed synthetic process. Dr Jones said: "At the moment, we don't have a full grasp of exactly how the fuel molecules are made, so we are now trying to find out exactly how this process unfolds. I hope that over the next 5-10 years we will be able to achieve commercially viable processes that will sustainably fuel our energy demands."

Explore further: Gasification of oil palm biomass to produce clean producer gas for heat, power generation

More information: Jones, P, R. et al. 'An engineered pathway for the biosynthesis of renewable propane'. Nature Communications, September 2014. dx.doi.org/10.1038/NCOMMS5731

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User comments : 17

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rfw
1 / 5 (4) Sep 02, 2014
This is the WRONG APPROACH!!! If we keep on burning organic materials (fossil OR bio-synthetics) we will keep adding CO2 and other combustion byproducts to the atmosphere and this will keep on exacerbating pollution and global "warming".

Lets focus on hacking photosynthesis instead.
tekram
5 / 5 (2) Sep 02, 2014

This is the WRONG APPROACH!!! ....Lets focus on hacking photosynthesis instead.

This paper clearly states "Their ultimate goal is to insert this engineered system into photosynthetic bacteria, so as to one day directly convert solar energy into chemical fuel."

In any case this group is far behind others, for example earlier, in Aug, 2014:
"Researchers at Argonne earlier filed a patent application on engineered photosynthetic bacteria that produce phytol (tetramethyl-2-hexadecen-1-ol), the physical and chemical properties of which (cetane number, heat of combustion, heat of vaporization, density, surface tension, etc.) correspond in magnitude to those of diesel fuel."

Shootist
1 / 5 (3) Sep 02, 2014
Abiogenic production of hydrocarbons.

Wunderbar.
Lex Talonis
1 / 5 (3) Sep 02, 2014
I wonder what will happen when these germs go feral?
Thorium Boy
1 / 5 (2) Sep 03, 2014
Every few months we get more "glad" news about some new method of creating alternatives to conventional fossil fuels. Algae, bacteria, whatever. None of them ever come to fruition. The reason is, you will never, ever create a fuel in this manner that is cheaper than what you can pump or dig out of the ground.
Thorium Boy
1 / 5 (2) Sep 03, 2014
This is the WRONG APPROACH!!! If we keep on burning organic materials (fossil OR bio-synthetics) we will keep adding CO2 and other combustion byproducts to the atmosphere and this will keep on exacerbating pollution and global "warming".

Lets focus on hacking photosynthesis instead.


Not to mention, propane vehicles emit a nauseating stench. One cab every now and again is ok, but a whole city full of propane cars would be intolerable.
ONTIME
1 / 5 (3) Sep 03, 2014
Man is not destroying the earth, there is much proof of this and global warming is a hoax, that is provable. This country has about another 150 years or so of fossil fuels in natural resources, we are on the verge of developing newer dependable means to prepare for the end of fossil fuel use. Nukes are still a viable option but we can with the right applicable technology go beyond this source, we just have to preserver and create the means to accomplish the task at hand. We need far better solar improvement, wind generation is not a answer but wave generation is a more constant source and the search for fusion goes on as our ability progresses and our tools we will find the answers to reliable energy....
Thorium Boy
1 / 5 (1) Sep 03, 2014
Man is not destroying the earth, there is much proof of this and global warming is a hoax, that is provable. This country has about another 150 years or so of fossil fuels in natural resources, we are on the verge of developing newer dependable means to prepare for the end of fossil fuel use. Nukes are still a viable option but we can with the right applicable technology go beyond this source, we just have to preserver and create the means to accomplish the task at hand. We need far better solar improvement, wind generation is not a answer but wave generation is a more constant source and the search for fusion goes on as our ability progresses and our tools we will find the answers to reliable energy....


I can't wait for the ships to start racking themselves up on these huge, just-offshore wave power generators. Nuclear power, in some form or other is the future of mass power. Solar and wind = energy poverty.
FainAvis
5 / 5 (2) Sep 03, 2014
Shootist: Try to make sense.

Abiogenic
adjective, Biology
1.
not resulting from the activity of living organisms.
dictionary.com
FainAvis
not rated yet Sep 03, 2014
ONTIME: You too. "preserver" [sic]. He meant persevere.
PPihkala
not rated yet Sep 03, 2014
Currently it seems that burning hydrogen might be the best answer to energy needs. Hydrogen made from water by Symphony 7, device made by Solar Hydrogen Trends: www.solarhydrogentrends.com
antialias_physorg
5 / 5 (4) Sep 03, 2014
If we keep on burning organic materials (fossil OR bio-synthetics) we will keep adding CO2 and other combustion byproducts to the atmosphere and this will keep on exacerbating pollution and global "warming".

E. Coli metabolises organic matter (i.e. stuff that was created at some point in the chain via plants capturing CO2). So even in the current lab setup this is carbon neutral.

Algae, bacteria, whatever. None of them ever come to fruition

From basic science to market ready product (much less to widespread adopted product) takes a decade. At least. This is not like in Hollywood movies: Invention now - fully functional gadget 20 seconds later.
11791
Sep 03, 2014
This comment has been removed by a moderator.
rfw
1 / 5 (2) Sep 03, 2014
Hi tekram, Thanks for your response: "This paper clearly states "Their ultimate goal is to insert this engineered system into photosynthetic bacteria, so as to one day directly convert solar energy into chemical fuel.""

Chemical fuels are THE problem to which I was referring and which we (the humans) do NOT need more of. The problem that needs solving is one of creating an electron source, and then a storage technology.
supamark23
4.3 / 5 (4) Sep 03, 2014
Hi tekram, Thanks for your response: "This paper clearly states "Their ultimate goal is to insert this engineered system into photosynthetic bacteria, so as to one day directly convert solar energy into chemical fuel.""

Chemical fuels are THE problem to which I was referring and which we (the humans) do NOT need more of. The problem that needs solving is one of creating an electron source, and then a storage technology.


You don't get it, the CO2 released by burning these newly produced fuels is the same CO2 the organisms pulled from the air to make the hydrocarbons 2 months previously - so it does not add more CO2, just cycles it around.
Noumenon
1 / 5 (2) Sep 03, 2014
^ racist above this post ^
rfw
not rated yet Sep 03, 2014
supamark23's comment "the CO2 released by burning these newly produced fuels is the same CO2 the organisms pulled from the air to make the hydrocarbons 2 months previously - so it does not add more CO2..."

Does combustion of organic fuels produce "pure" CO2? I don't think so.... How much energy is utilized for the production of these modified bacteria? I think LOTS.

I suggest that there are many much better pathways available.
Mike_Massen
not rated yet Sep 05, 2014
ONTIME muttered whilst his head's in the sand:-
Man is not destroying the earth, there is much proof of this and global warming is a hoax, that is provable.
Pollution occured to you ever - Really ?

What are the top 5 'proofs' of the hoax ?

Does physics come into it - do you have an education re heat, statistical mechanics, properties of gases & water etc ?

How about measurements ?

How about the fact we, as humans, are burning the equivalent of some 230,000 Litres of petrol/second - adding GHGs & heat to the worlds atmosphere & ultimately oceans ?

Seen this ? Open your closed mind redneck bias up ONTIME...!

http://www.woodfo...o2/every

AND

http://www.woodfo...rg/notes

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