Featured Research

from universities, journals, and other organizations

Engineer converts yeast cells into 'sweet crude' biofuel

Date:
January 22, 2014
Source:
University of Texas at Austin
Summary:
A chemical engineer has developed a new source of renewable energy -- a yeast cell-based platform for producing biodiesel, which he has dubbed "sweet crude." The key to this platform is regular table sugar. It has the potential for industry scalability without the environmental costs of other biofuels.

Left: Starting cells with around 15 percent lipid content. Right: Engineered cells with nearly 90 percent lipid content.
Credit: Image courtesy of University of Texas at Austin

Researchers at The University of Texas at Austin's Cockrell School of Engineering have developed a new source of renewable energy, a biofuel, from genetically engineered yeast cells and ordinary table sugar. This yeast produces oils and fats, known as lipids, that can be used in place of petroleum-derived products.

Assistant professor Hal Alper, in the Cockrell School's McKetta Department of Chemical Engineering, along with his team of students, created the new cell-based platform. Given that the yeast cells grow on sugars, Alper calls the biofuel produced by this process "a renewable version of sweet crude."

The researchers' platform produces the highest concentration of oils and fats reported through fermentation, the process of culturing cells to convert sugar into products such as alcohol, gases or acids. This work was published in Nature Communications on Jan. 20.

The UT Austin research team was able to rewire yeast cells to enable up to 90 percent of the cell mass to become lipids, which can then be used to produce biodiesel.

"To put this in perspective, this lipid value is approaching the concentration seen in many industrial biochemical processes," Alper said. "You can take the lipids formed and theoretically use it to power a car."

Since fatty materials are building blocks for many household products, this process could be used to produce a variety of items made with petroleum or oils -- from nylon to nutrition supplements to fuels. Biofuels and chemicals produced from living organisms represent a promising portion of the renewable energy market. Overall, the global biofuels market is expected to double during the next several years, going from $82.7 billion in 2011 to $185.3 billion in 2021.

"We took a starting yeast strain of Yarrowia lipolytica, and we've been able to convert it into a factory for oil directly from sugar," Alper said. "This work opens up a new platform for a renewable energy and chemical source."

The biofuel the researchers formulated is similar in composition to biodiesel made from soybean oil. The advantages of using the yeast cells to produce commercial-grade biodiesel are that yeast cells can be grown anywhere, do not compete with land resources and are easier to genetically alter than other sources of biofuel.

"By genetically rewiring Yarrowia lipolytica, Dr. Alper and his research group have created a near-commercial biocatalyst that produces high levels of bio-oils during carbohydrate fermentation," said Lonnie O. Ingram, director of the Florida Center for Renewable Chemicals and Fuels at the University of Florida. "This is a remarkable demonstration of the power of metabolic engineering."

So far, high-level production of biofuels and renewable oils has been an elusive goal, but the researchers believe that industry-scale production is possible with their platform.

In a large-scale engineering effort spanning over four years, the researchers genetically modified Yarrowia lipolytica by both removing and overexpressing specific genes that influence lipid production. In addition, the team identified optimum culturing conditions that differ from standard conditions. Traditional methods rely on nitrogen starvation to trick yeast cells into storing fat and materials. Alper's research provides a mechanism for growing lipids without nitrogen starvation. The research has resulted in a technology for which UT Austin has applied for a patent.

"Our cells do not require that starvation," Alper said. "That makes it extremely attractive from an industry production standpoint."

The team increased lipid levels by nearly 60-fold from the starting point.

At 90 percent lipid levels, the platform produces the highest levels of lipid content created so far using a genetically engineered yeast cell. To compare, other yeast-based platforms yield lipid content in the 50 to 80 percent range. However, these alternative platforms do not always produce lipids directly from sugar as the UT Austin technology does.

Alper and his team are continuing to find ways to further enhance the lipid production levels and develop new products using this engineered yeast.

This research was funded by the Office of Naval Research Young Investigator Program, the DuPont Young Professor Grant and the Welch Foundation under grant F-1753.


Story Source:

The above story is based on materials provided by University of Texas at Austin. Note: Materials may be edited for content and length.


Journal Reference:

  1. John Blazeck, Andrew Hill, Leqian Liu, Rebecca Knight, Jarrett Miller, Anny Pan, Peter Otoupal, Hal S. Alper. Harnessing Yarrowia lipolytica lipogenesis to create a platform for lipid and biofuel production. Nature Communications, 2014; 5 DOI: 10.1038/ncomms4131

Cite This Page:

University of Texas at Austin. "Engineer converts yeast cells into 'sweet crude' biofuel." ScienceDaily. ScienceDaily, 22 January 2014. <www.sciencedaily.com/releases/2014/01/140122091950.htm>.
University of Texas at Austin. (2014, January 22). Engineer converts yeast cells into 'sweet crude' biofuel. ScienceDaily. Retrieved July 31, 2014 from www.sciencedaily.com/releases/2014/01/140122091950.htm
University of Texas at Austin. "Engineer converts yeast cells into 'sweet crude' biofuel." ScienceDaily. www.sciencedaily.com/releases/2014/01/140122091950.htm (accessed July 31, 2014).

Share This




More Earth & Climate News

Thursday, July 31, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Visitors Feel Part of the Pack at Wolf Preserve

Visitors Feel Part of the Pack at Wolf Preserve

AP (July 31, 2014) Seacrest Wolf Preserve on the northern Florida panhandle allows more than 10,000 visitors each year to get up close and personal with Arctic and British Columbian Wolves. (July 31) Video provided by AP
Powered by NewsLook.com
Florida Panther Rebound Upsets Ranchers

Florida Panther Rebound Upsets Ranchers

AP (July 31, 2014) With Florida's panther population rebounding, some ranchers complain the protected predators are once again killing their calves. (July 31) Video provided by AP
Powered by NewsLook.com
Big Waves In Arctic Ocean Threaten Polar Ice

Big Waves In Arctic Ocean Threaten Polar Ice

Newsy (July 30, 2014) Big waves in parts of the Arctic Ocean are unprecedented, mainly because they used to be covered in ice. Video provided by Newsy
Powered by NewsLook.com
Raw: Thousands Flocking to German Crop Circle

Raw: Thousands Flocking to German Crop Circle

AP (July 30, 2014) Thousands of people are trekking to a Bavarian farmer's field to check out a mysterious set of crop circles. (July 30) Video provided by AP
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:
from the past week

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile: iPhone Android Web
Follow: Facebook Twitter Google+
Subscribe: RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins