SHAFAQNA Currently, producing fuel directly from biological products can lead to some tough choices. The resulting biofuel usually either needs to be mixed with regular petroleum or the vehicles themselves need to be modified to work with it. New research published recently details the work of scientists to try to avoid both problems by creating a biofuel that's compatible with diesel engines. "Producing a commercial biofuel that can be used without needing to modify vehicles has been the goal of this project from the outset," says Professor John Love of the University of Exeter. The study (funded by Shell), used E. coli to create the "bio-fossil-fuels," as Love calls them, though this biofuel is a long way from your gas tank. It takes around 100 liters of bacteria to create a teaspoon of fuel, the BBC reports, and the researchers expect it will be three to five years before they will know whether the yield can be improved.
On another E. coli biofuel track, Ars Technica details a separate study that advances production in perhaps a more significant — or at least more voluminous — way. In that study, researchers took techniques from the pharmaceutical industry and applied them to biofuel production. Specifically, they created a way to get E. coli to excrete the fuel after it has been created — normally the fuel sticks around and kills the bacteria. “It’s the same idea as milking a cow,” Professor Geoffrey Chang told Ars Technica. The method could make producing biofuel much more efficient, since the same bacteria can continue to produce fuel without needing to be replaced.
SHAFAQNA (Shia International News Association) – Researchers genetically modified E. coli bacteria to convert sugar into an oil that is almost identical to conventional diesel.
If the process could be scaled up, this synthetic fuel could be a viable alternative to the fossil fuel, the team said.
The study is published in the Proceedings of the National Academy of Sciences.
Professor John Love, a synthetic biologist from the University of Exeter, said: "Rather than making a replacement fuel like some biofuels, we have made a substitute fossil fuel.
"The idea is that car manufacturers, consumers and fuel retailers wouldn't even notice the difference - it would just become another part of the fuel production chain."
There is a push to increase the use of biofuels around the world.
In the European Union, a 10% target for the use of these crop-based fuels in the transport sector has been set for 2020.
But most forms of biodiesel and bioethanol that are currently used are not fully compatible with modern engines. Fractions of the substances (between 5-10%) need to be blended with petroleum before they can be used in most engines.
However, the fuel produced by the modified E. coli bacteria is different.
Prof Love explained: "What we've done is produced fuels that are exactly the chain length required for the modern engine and exactly the composition that is required.
"They are bio-fossil-fuels if you like."
To create the fuel, the researchers, who were funded by the oil company Shell and the Biotechnology and Biological Sciences Research Council, used a strain of E. coli that usually takes in sugar and then turns it into fat.
Using synthetic biology, the team altered the bacteria's cell mechanisms so that the sugar was converted to synthetic fuel molecules instead.
By altering the bacteria's genes, they were able to transform the bugs into fuel-producing factories. However, the E. coli did not make much of the alkane fuel.
Professor Love said it would take about 100 litres of bacteria to produce a single teaspoon of the fuel.
"Our challenge is to increase the yield before we can go into any form of industrial production," he said.
"We've got a timeframe of about three to five years to do that and see if it is worth going ahead with it."
The team is also looking to see if the bacteria can convert any other products into fuel, such as human or animal waste.
Biofuels are considered to be a greener alternative to fossil fuels.
While petrol and diesel release carbon dioxide that has been stored deep within the Earth, biofuels are said to be carbon neutral because they release as much CO2 into the atmosphere as the plants they are made from absorbed.
However, the energy it takes to grow and process the crops needed for biofuels also should be taken into account, as this adds to their "carbon footprint".
A recent report by Chatham House said biofuels were expensive and worse for the climate than fossil fuels.
According to Geraint Evans, a biofuel consultant at the NNFCC (formerly known as the National Non-Food Crops Centre), these issues would need to be taken into account for a bacteria-produced fuel too.
"It widens the potential sources you can use to make diesel," he said.
"But we still need to consider that this is coming from the land and the sustainability needs to be carefully considered.
It's not a magic bullet - but it is another tool in the toolbox."-www.shafaqna.com/English
SHAFAQNA (Shia International News Association) – The biology behind termite digestion may lead to a better way to break down biomass and make biofuels, researchers say.
A recent study on how termites break down woody materials, which focused on the symbiotic relationship between the insect and the bacteria living in its gut, found that bacteria apparently have little, if anything, to do with termite digestion.
Michael Scharf, professor in urban entomology at Purdue University, and collaborators at the University of Florida wanted to see how diet affected those bacteria. If the bacteria play a role in digestion, the type of materials the insect eats should affect the composition of the bacterial community living in the termite gut.
More than 4,500 different species of bacteria were cataloged in termite guts. When multiple colonies of termites were independently fed diets of wood or paper, however, those bacteria were unaffected.
“You would think diet would cause huge ecological shifts in bacterial communities, but it didn’t. We didn’t detect any statistical differences,” Scharf says.
What they did see were far more significant changes in gene expression in the termites and the protists that live in the insects’ guts along with the bacteria.
“The bacteria communities seem very stable, but the host and the protozoa gene expression are changing a lot based on diet,” Scharf says.
The scientists looked at 10,000 gene sequences from the termites and protists to determine which genes were expressed based on differing diets. Termites and protists fed woody and lignin-rich diets changed expression of about 500 genes, leading Scharf to believe those genes might be important for breaking down lignin, a rigid material in plant cell walls that isn’t easily broken down when making biofuels.
“We see much more of the playing field now,” Scharf says.
Understanding which genes are involved in digestion should help researchers track down the enzymes that actually break down woody materials in termite digestion. Those enzymes may be tools scientists could use to better break down biomass and extract sugars during biofuel production.
The National Science Foundation, the Consortium for Plant Biotechnology Inc., and the US Department of Energy funded the research. The findings were detailed in three papers published in the journals Molecular Ecology, Insect Molecular Biology, and Insect Biochemistry and Molecular Biology.-www.shfaqna.com/English
SHAFAQNA (Shia international Association) — Scientists have discovered a biological switch in blue-green algae that reacts to light and changes how electrons are transported within the cells. The new findings could help in engineering algae for improved biofuel production. The results of the research were published on July 10, 2012 in Proceedings of the National Academy of Sciences.
Blue-green algae, also known as cyanobacteria, are well known for their explosive growth when given the right combination of light, nutrients and warm water. Due in part to their high growth rate, their ability to use wastewater as a source for nutrients and their ability to grow without competing with arable land used to grow food, cyanobacteria and other types of algae have become a prime target for biofuel production.
Lack of light is often a major constraint in algae biofuel production systems because algae need light to photosynthesize. Attempts to increase the amount of light delivered to algae in bioreactors typically involve the use of energy-demanding mixing systems or smaller and more expensive growth chambers.
Alternatively, scientists could try to improve the way that algae grow under low light conditions. But first, they need to more fully understand how the biological molecules within cells respond to light.
To examine how cyanobacterial cells respond to light, scientists attached a green fluorescent protein tag to two key respiratory complexes in the species Synechococcus elongatus. Then, they exposed the cyanobacterial cells to either low light or moderate light conditions in the laboratory and tracked changes in the cells by viewing the cells under a microscope.
The scientists discovered that brighter light caused the respiratory complexes to redistribute throughout the cells from discrete patches into more evenly distributed locations. The redistribution of respiratory complexes appeared to be triggered by changes in the redox state of an electron carrier close to plastiquinone, and resulted in a major increase in the probability that electrons would be transferred to photosystem I, an integral component of the photosynthetic complex shown in the diagram below.
The research was carried out by seven scientists from Queen Mary, University of London, the Imperial College London and the University College London.
Conrad Mullineaux, who is a Professor of Microbiology at Queen Mary, University of London and co-author of the new paper, commented on the findings in a press release. He said:
Any organism that breathes or photosynthesizes depends on tiny electrical circuits operating within biological membranes. We are trying to find out what controls these circuits: what makes the electrons take the routes that they do, and what switches are available to send the electrons to other destinations?
He commented on the new findings further in an interview with Ecoimagination:
It’s rather like a familiar electrical switch. You press on it to change the position of the wires, and thereby change what the electrons do. At this state, we’re just trying to understand what’s happening in the cell. But the potential is there to exploit the knowledge for biofuel production.
Bottom line: Scientists have discovered a biological switch in cyanobacteria that reacts to light and changes how electrons are transported within the cells. The new findings could help in engineering blue-green algae for improved biofuel production. The results of the research were published on July 10, 2012 in Proceedings of the National Academy of Sciences.—www.shafaqna.com/english