(Press-News.org) UCLA chemical engineering researchers have created a new synthetic metabolic pathway for breaking down glucose that could lead to a 50 percent increase in the production of biofuels.
The new pathway is intended to replace the natural metabolic pathway known as glycolysis, a series of chemical reactions that nearly all organisms use to convert sugars into the molecular precursors that cells need. Glycolysis converts four of the six carbon atoms found in glucose into two-carbon molecules known acetyl-CoA, a precursor to biofuels like ethanol and butanol, as well as fatty acids, amino acids and pharmaceuticals. However, the two remaining glucose carbons are lost as carbon dioxide.
Glycolysis is currently used in biorefinies to convert sugars derived from plant biomass into biofuels, but the loss of two carbon atoms for every six that are input is seen as a major gap in the efficiency of the process. The UCLA research team's synthetic glycolytic pathway converts all six glucose carbon atoms into three molecules of acetyl-CoA without losing any as carbon dioxide.
The research is published online Sept. 29 in the peer-reviewed journal Nature.
The principal investigator on the research is James Liao, UCLA's Ralph M. Parsons Foundation Professor of Chemical Engineering and chair of the chemical and biomolecular engineering department. Igor Bogorad, a graduate student in Liao's laboratory, is the lead author.
"This pathway solved one of the most significant limitations in biofuel production and biorefining: losing one-third of carbon from carbohydrate raw materials," Liao said. "This limitation was previously thought to be insurmountable because of the way glycolysis evolved."
This synthetic pathway uses enzymes found in several distinct pathways in nature.
The team first tested and confirmed that the new pathway worked in vitro. Then, they genetically engineered E. coli bacteria to use the synthetic pathway and demonstrated complete carbon conservation. The resulting acetyl-CoA molecules can be used to produce a desired chemical with higher carbon efficiency. The researchers dubbed their new hybrid pathway non-oxidative glycolysis, or NOG.
"This is a fundamentally new cycle," Bogorad said. "We rerouted the most central metabolic pathway and found a way to increase the production of acetyl-CoA. Instead of losing carbon atoms to CO2, you can now conserve them and improve your yields and produce even more product."
The researchers also noted that this new synthetic pathway could be used with many kinds of sugars, which in each case have different numbers of carbon atoms per molecule, and no carbon would be wasted.
"For biorefining, a 50 percent improvement in yield would be a huge increase," Bogorad said. "NOG can be a nice platform with different sugars for a 100 percent conversion to acetyl-CoA. We envision that NOG will have wide-reaching applications and will open up many new possibilities because of the way we can conserve carbon."
The researchers also suggest this new pathway could be used in biofuel production using photosynthetic microbes.
The paper's other author is Tzu-Shyang Lin, who recently received a bachelor's degree from UCLA in chemical engineering.
INFORMATION:
The UCLA Henry Samueli School of Engineering and Applied Science, established in 1945, offers 28 academic and professional degree programs and has an enrollment of more than 5,000 students. The school's distinguished faculty are leading research to address many of the critical challenges of the 21st century, including renewable energy, clean water, health care, wireless sensing and networking, and cyber-security. Ranked among the top 10 engineering schools at public universities nationwide, the school is home to eight multimillion-dollar interdisciplinary research centers in wireless sensor systems, wireless health, nanoelectronics, nanomedicine, renewable energy, customized computing, the smart grid, and the Internet, all funded by federal and private agencies and individual donors.
For more news, visit the UCLA Newsroom and follow us on Twitter.
END
Membrane proteins are responsible for transporting chemicals and messages between a cell and its environment. But determining their structure has proved challenging for scientists. A study by UC Santa Barbara's Han Research Group demonstrates a new tool to resolve the structure of membrane-embedded and membrane-associating proteins using the water dynamics gradient they found across and above the lipid bilayer as a unique ruler.
More than 25 percent of all human proteins are membrane proteins, which perform other essential functions, such as sensing and signaling. They ...
LA JOLLA, CA—September 30, 2013¬–A team led by scientists at The Scripps Research Institute (TSRI) has created the first comprehensive roadmap of the protein interactions that enable cells in the pancreas to produce, store and secrete the hormone insulin. The finding makes possible a deeper scientific understanding of the insulin secretion process—and how it fails in insulin disorders such as type 2 diabetes.
"The development of this insulin interaction map is unprecedented, and we expect it to lead us to new therapeutic approaches for type 2 diabetes," said William E. ...
COLUMBIA, Mo. ¬— As the oldest of the baby boomers begin to reach retirement age, a large percentage of Americans are thinking more and more about how much money they must save to be able to retire comfortably. Also, more and more employers are changing retirement benefits from defined-benefit plans, which guarantee some level of retirement income, to defined-contribution plans, which require employees to invest on their own for retirement. All of these changes, plus the recent economic recession, have created a difficult financial environment for future retirees. Now, ...
MADISON — Scientists at the University of Wisconsin-Madison have made a discovery that, if replicated in humans, suggests a shortage of zinc may contribute to diseases like Alzheimer's and Parkinson's, which have been linked to defective proteins clumping together in the brain.
With proteins, shape is everything. The correct shape allows some proteins to ferry atoms or molecules about a cell, others to provide essential cellular scaffolding or identify invading bacteria for attack. When proteins lose their shape due to high temperature or chemical damage, they stop working ...
VIDEO:
NASA planetary scientist Conor Nixon explains his discovery of propylene on Titan, Saturn's largest moon. Scientists have known about the presence of atmospheric hydrocarbons on Titan since Voyager 1 flew...
Click here for more information.
NASA's Cassini spacecraft has detected propylene, a chemical used to make food-storage containers, car bumpers and other consumer products, on Saturn's moon Titan.
This is the first definitive detection of the plastic ingredient ...
WASHINGTON, DC, September 26, 2013 -- In response to past economic crises such as the Great Depression, Americans demanded government policy solutions to widespread unemployment and rising income insecurity. But a new study in the October issue of the American Sociological Review found that public support for government efforts to address social problems actually declined in the wake of the 2008 economic crisis.
"We found it surprising that as the Great Recession emerged, the American public moved quickly toward lower levels of support for government policy solutions ...
To address the global phenomenon of disparities in respiratory health, the American Thoracic Society and the European Respiratory Society have released an official policy statement in which each pledges its commitment to reducing health disparities between the lowest and highest socioeconomic groups by continuing or initiating work with leaders from governments, academia, and other organizations to promote scientific inquiry and training, disseminate medical information and best practices, and monitor and advocate for public respiratory health.
The statement appears in ...
Philadelphia, PA, October 1, 2013 -- Resveratrol, a naturally occurring polyphenol compound produced by the skin of red grapes and peanuts, and found in red wine, has been touted as a beneficial supplement due to its anti-inflammatory and antioxidant properties. This has been supported by some experimental studies, whereas others suggest a lack of benefit. A new study using two multiple sclerosis (MS) models published in The American Journal of Pathology has found that resveratrol actually worsened MS-like neuropathology and inflammation and had no neuroprotective effects. ...
A recent research has explored the environmental exposure and flux of thallium to the environment; and it provides the foundations for theoretical calculation to control Tl pollution by utilizing of Tl-rich pyrite minerals.
This paper, "Environmental Exposure and Flux of Thallium by Industrial Activities Utilizing Thallium-Bearing Pyrite", written by professor CHEN Yong-Heng et al. from Key Laboratory of Waters Safety & Protection in the Pearl River Delta, Ministry of Education, Guangzhou University, is published in Science China: Earth Sciences (No.9, 2013) .
Thallium ...
Unique DNA markings on certain genes may "predict" the risk of developing head and neck cancer, according to new research led by Queen Mary University of London.
The findings, published today in the journal Cancer, raise the potential for the development of non-invasive tests which could pick up these tell-tale signs of early cancer initiation.
Head and neck cancers are cancers that develop anywhere in the head and neck, including mouth cancer and throat cancer. About 16,000 people in the UK are diagnosed with head and neck cancer every year*.
In this study scientists ...