Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Gene discovery potential key to cost-competitive cellulosic ethanol

21.05.2010
Scientists at the Department of Energy's Oak Ridge National Laboratory are improving strains of microorganisms used to convert cellulosic biomass into ethanol, including a recent modification that could improve the efficiency of the conversion process.

Biofuels researchers and industrials have generated improved mutant microorganisms previously, but authors of a paper in the on-line Proceedings of the National Academy of Sciences identify a key Z. mobilis gene for the first time and show the strain's improved efficiency and its potential use for more cost-effective biofuel production.

"Microbes have been breaking down plant material to access sugars for millennia, so plants have evolved to have very sophisticated cell structures that make accessing these sugars difficult," said Steven Brown, staff microbiologist in the Biosciences Division and one of the inventors of the improved Z. mobilis strain.

Currently, biomass materials like corn stover and switchgrass must undergo a series of pretreatments to loosen the cellular structure enough to extract the sugar cellulose. Brown said these treatments add new challenges because, although they are necessary, they create a range of chemicals known as inhibitors that stall or stop microorganisms like Z. mobilis from performing the fermentation.

"There are two ways to combat recalcitrance, or the difficulty created by the inhibitors," Brown said. "One way is to remove the inhibitors, but this method is very expensive and would not help biofuels become cost-competitive with gasoline. The second way is what we do, which is to develop microorganisms that are more tolerant of the inhibitors."

The non-mutated strain of Z. mobilis, for instance, cannot grow in the presence of one of the predominant inhibitors, acetate. However, when gene nhaA is over-expressed by inserting a slice of DNA containing the gene into the non-mutated strain, the bacterium can withstand acetate in its environment.

Brown and lead author Shihui Yang did not stop with Z. mobilis but looked at related genes in other microorganisms and found that the method translates in different organisms.

"We took this gene and integrated it into a strain of yeast, and the improvements carried over into the yeast," Yang said.

Brown says this method of processing biomass for ethanol has the potential to become a "tool kit" — a combination of mutant genes that reduce the impact of specific inhibitors. The tool kit could expand quickly, too, as scientists now have more advanced DNA sequencing technology available to identify and resequence genes.

"The DNA sequencer we used was unavailable as recently as five years ago, and it has unprecedented sequencing capabilities. It is 4,000 times more powerful than the machine that finished sequencing the human genome almost a decade ago," Brown said.

ORNL microbiologists are currently sequencing other microorganisms used in biofuels production that could also be advantageous if genetically altered to resist different types of inhibitors.

"By looking at the behavioral response to the genetic changes in this bacteria, Zymomonas, we can then look forward to improving other bacteria," Yang said.

ORNL is managed by UT-Battelle for the Department of Energy's Office of Science.

Katie Freeman | EurekAlert!
Further information:
http://www.ornl.gov

Further reports about: DNA DNA sequencer Science TV Z. mobilis gasoline human genome

More articles from Life Sciences:

nachricht Water forms 'spine of hydration' around DNA, group finds
26.05.2017 | Cornell University

nachricht How herpesviruses win the footrace against the immune system
26.05.2017 | Helmholtz-Zentrum für Infektionsforschung

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Can the immune system be boosted against Staphylococcus aureus by delivery of messenger RNA?

Staphylococcus aureus is a feared pathogen (MRSA, multi-resistant S. aureus) due to frequent resistances against many antibiotics, especially in hospital infections. Researchers at the Paul-Ehrlich-Institut have identified immunological processes that prevent a successful immune response directed against the pathogenic agent. The delivery of bacterial proteins with RNA adjuvant or messenger RNA (mRNA) into immune cells allows the re-direction of the immune response towards an active defense against S. aureus. This could be of significant importance for the development of an effective vaccine. PLOS Pathogens has published these research results online on 25 May 2017.

Staphylococcus aureus (S. aureus) is a bacterium that colonizes by far more than half of the skin and the mucosa of adults, usually without causing infections....

Im Focus: A quantum walk of photons

Physicists from the University of Würzburg are capable of generating identical looking single light particles at the push of a button. Two new studies now demonstrate the potential this method holds.

The quantum computer has fuelled the imagination of scientists for decades: It is based on fundamentally different phenomena than a conventional computer....

Im Focus: Turmoil in sluggish electrons’ existence

An international team of physicists has monitored the scattering behaviour of electrons in a non-conducting material in real-time. Their insights could be beneficial for radiotherapy.

We can refer to electrons in non-conducting materials as ‘sluggish’. Typically, they remain fixed in a location, deep inside an atomic composite. It is hence...

Im Focus: Wafer-thin Magnetic Materials Developed for Future Quantum Technologies

Two-dimensional magnetic structures are regarded as a promising material for new types of data storage, since the magnetic properties of individual molecular building blocks can be investigated and modified. For the first time, researchers have now produced a wafer-thin ferrimagnet, in which molecules with different magnetic centers arrange themselves on a gold surface to form a checkerboard pattern. Scientists at the Swiss Nanoscience Institute at the University of Basel and the Paul Scherrer Institute published their findings in the journal Nature Communications.

Ferrimagnets are composed of two centers which are magnetized at different strengths and point in opposing directions. Two-dimensional, quasi-flat ferrimagnets...

Im Focus: World's thinnest hologram paves path to new 3-D world

Nano-hologram paves way for integration of 3-D holography into everyday electronics

An Australian-Chinese research team has created the world's thinnest hologram, paving the way towards the integration of 3D holography into everyday...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Marine Conservation: IASS Contributes to UN Ocean Conference in New York on 5-9 June

24.05.2017 | Event News

AWK Aachen Machine Tool Colloquium 2017: Internet of Production for Agile Enterprises

23.05.2017 | Event News

Dortmund MST Conference presents Individualized Healthcare Solutions with micro and nanotechnology

22.05.2017 | Event News

 
Latest News

How herpesviruses win the footrace against the immune system

26.05.2017 | Life Sciences

Water forms 'spine of hydration' around DNA, group finds

26.05.2017 | Life Sciences

First Juno science results supported by University of Leicester's Jupiter 'forecast'

26.05.2017 | Physics and Astronomy

VideoLinks
B2B-VideoLinks
More VideoLinks >>>