14 DAY TRIAL // Writing in a recent issue of the journal Nature Communications, a team of researchers working with the University of Texas at Austin in the United States detail how, using nothing but “pleasantly plump” yeast and run-off-the-mill sugar, they managed to brew themselves some biofuel.
In their paper, the researchers explain that, in order to be able to use the yeast to produce biofuel, they had to modify its genetic makeup.
The strain of yeast that they got to toy with is known to the scientific community as Yarrowia lipolytica.
What the University of Texas at Austin researchers did as part of their experiments was to remove some of this microorganism's genes, and overexpress others.
The genes that they targeted all influenced lipid production.
After being genetically engineered in this manner, the yeast ended up producing significantly more lipids than its parent strains did.
Specifically, 90% of its cell mass comprised lipids that the scientists were able to harvest and use to make biofuel.
As detailed on the official website for the University of Texas at Austin, the yeast used in this series of experiments was grown on sugar.
Because of this, researcher Hal Aler liked to refer to the renewable energy source obtained from yeast-based lipids as sweet crude biofuel.
"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," Hal Aler explained.
"This work opens up a new platform for a renewable energy and chemical source," he added.
Interestingly enough, it would appear that the yeast created by these scientists is the most prolific in terms of production of lipids that has until now been obtained through genetic engineering.
Other yeast-based platforms that the scientific community has until now documented yield a 50-80% lipid content.
"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."
"This is a remarkable demonstration of the power of metabolic engineering," researcher Lonnie O. Ingram with the University of Florida commented on the work of the University of Texas at Austin scientists.