Kentucky researchers unlock promise of ancient algae strain

| July 14, 2011

Botryococcus braunii, an ancient strain of algae more than 500 million years old that researchers say is responsible for creating oil and coal shale deposits, may not grow fast enough for advanced biofuels consideration, but its genetic blueprints still have a high value. Joe Chappell, an agriculture professor from the University of Kentucky, has teamed up with several of his doctoral students at UK, along with members of other schools and even Sapphire Energy, to study the strain of algae.

The most recent work by the team has uncovered and isolated the genes responsible in the strain that help it to produce high quantities of lipid oil. The team then genetically engineered a yeast strain with the traits from the algae strain in an effort to put its high-oil producing traits to the test. “This represents the culmination of an outstanding effort to understand a fundamental process that has direct ramifications for a real-world problem­­­—how are we going to generate a truly renewable biofuels supply,” Chappell said on the work. Part of the reason the team has taken a strong interest in this particular strain of algae is because, according to the team, the strain is one of the only known organisms to actually be responsible for the oil and coal shale deposits that are used today in the petrochemical industry. The strain, according to Chappell, “has been the target of studies from the large chemical and petrochemical industries.”

Tim Devarenne, a graduate of UK who is currently a professor of biochemistry and biophysics at Texas A&M University, helped Chappell and his team on the work. According to Devarenne, “this study identifies a very remarkable molecular mechanism for the production of hydrocarbons that,” he said, “as far as we can tell, is not found in any other organism. Thus,” he added, “it offers a unique insight into how hydrocarbons were produced hundreds of millions of years ago.”

The genetic characterization work by Chappell and his team isn’t the only effort they have put towards this particular strain of algae. In the spring, he received almost $1 million in grant funding from the USDA to engineer plants that would be able to produce oils similar to the oils created by the ancient strain. The ultimate goal is to engineer plants, including tobacco, sorghum or miscanthus, “with the goal of mimicking the production of this unique oil in terrestrial plants and leading to a renewable production platform for petroleum deposits,” according to UK.

Members of Chappell’s team have also created a short video showing the energy promise within the strain of algae. In the video, Tom Niehaus, a doctoral student on the team, is filmed comparing the Botryococcus braunii strain with another algae strain, Chlamydomonas. To compare the two strains and show the energy content difference between the two, Niehaus dried a small amount of each strain onto the ends of two glass stirring rods. “We will see what happens when we try and light these on fire,” he said. He then took two matches and lit the ends of the stirring rods on fire. Within seconds, the rod with dried Chlamydomonas burned up, but the Botryococcus braunii dried rod burned for nearly 35 seconds. As Niehaus explained, that is because the oil content in the strain is roughly 20 to 30 percent. “There is much more energy” in the strain, he said, while watching the stirring rod tip glowing roughly the size of two matches burning in unison.