Nathan Mosier, an associate professor of agricultural and biological engineering; Miroslav Sedlak, a research assistant professor of agricultural and biological engineering; and Nancy Ho, a research professor of chemical engineering, used genes from a fungus to re-engineer a yeast strain Ho developed at Purdue. The new yeast can ferment the sugar arabinose in addition to the other sugars found in plant material such as corn stalks, straw, switchgrass and other crop residues.
"Natural yeast can ferment three sugars: galactose, manose and glucose," Ho said. "The original Ho yeast added xylose to that, and now the fifth, arabinose, has been added."
The addition of new genes to the Ho yeast strain should increase the amount of ethanol that can be produced from cellulosic material. Arabinose makes up about 10 percent of the sugars contained in those plants.
In addition to creating this new arabinose-fermenting yeast, Mosier, Sedlak and Ho also were able to develop strains that are more resistant to acetic acid. Acetic acid, the main ingredient in vinegar, is natural to plants and released with sugars before the fermentation process during ethanol production. Acetic acid gets into yeast cells and slows the fermentation process, adding to the cost of ethanol production.
"It inhibits the microorganism. It doesn't produce as much biofuel, and it produces it more slowly," Mosier said. "If it slows down too much, it's not a good industrial process."
Mosier, Sedlak and Ho compared the genes in the more resistant strains to others to determine which genes made the yeast more resistant to acetic acid. By improving the expression of those genes, they increased the yeast's resistance.
Mosier said arabinose is broken down in the same way as the other four sugars except for the first two steps. Adding the fungus genes allowed the yeast to create necessary enzymes to get through those steps.
"This gave the yeast a new tool set," Sedlak said. "This gives the yeast the tools it needs to get arabinose into the chain."
The team's findings on acetic acid were published in the June issue of the journal FEMS Yeast Research. The findings on arabinose were published in the early online version of the journal Applied Microbiology and Biotechnology.
Mosier, Sedlak and Ho will continue to improve the yeast to make it more efficient during industrial ethanol production and more resistant to inhibitors. The. U.S. Department of Energy funded their research.Writer: Brian Wallheimer, 765-496-2050, email@example.com
Brian Wallheimer | EurekAlert!
Researchers identify potentially druggable mutant p53 proteins that promote cancer growth
09.12.2016 | Cold Spring Harbor Laboratory
Plant-based substance boosts eyelash growth
09.12.2016 | Fraunhofer-Institut für Angewandte Polymerforschung IAP
Physicists of the University of Würzburg have made an astonishing discovery in a specific type of topological insulators. The effect is due to the structure of the materials used. The researchers have now published their work in the journal Science.
Topological insulators are currently the hot topic in physics according to the newspaper Neue Zürcher Zeitung. Only a few weeks ago, their importance was...
In recent years, lasers with ultrashort pulses (USP) down to the femtosecond range have become established on an industrial scale. They could advance some applications with the much-lauded “cold ablation” – if that meant they would then achieve more throughput. A new generation of process engineering that will address this issue in particular will be discussed at the “4th UKP Workshop – Ultrafast Laser Technology” in April 2017.
Even back in the 1990s, scientists were comparing materials processing with nanosecond, picosecond and femtosesecond pulses. The result was surprising:...
Have you ever wondered how you see the world? Vision is about photons of light, which are packets of energy, interacting with the atoms or molecules in what...
A multi-institutional research collaboration has created a novel approach for fabricating three-dimensional micro-optics through the shape-defined formation of porous silicon (PSi), with broad impacts in integrated optoelectronics, imaging, and photovoltaics.
Working with colleagues at Stanford and The Dow Chemical Company, researchers at the University of Illinois at Urbana-Champaign fabricated 3-D birefringent...
In experiments with magnetic atoms conducted at extremely low temperatures, scientists have demonstrated a unique phase of matter: The atoms form a new type of quantum liquid or quantum droplet state. These so called quantum droplets may preserve their form in absence of external confinement because of quantum effects. The joint team of experimental physicists from Innsbruck and theoretical physicists from Hannover report on their findings in the journal Physical Review X.
“Our Quantum droplets are in the gas phase but they still drop like a rock,” explains experimental physicist Francesca Ferlaino when talking about the...
16.11.2016 | Event News
01.11.2016 | Event News
14.10.2016 | Event News
09.12.2016 | Life Sciences
09.12.2016 | Ecology, The Environment and Conservation
09.12.2016 | Health and Medicine