It's summer, and that typically means you can find fields of algae covering local ponds. While most of us consider this 'pond scum' to be rather unpleasant, the U.S. Department of Energy (DOE) has taken a keen interest. As a potential source of a home-grown sustainable fuel, algae holds great promise. And according to a new study published in the journal Nature Plants, scientists are one step closer to delivering on that promise.
The Future of Energy?
Algae are small aquatic organisms that have photosynthetic abilities. In other words, like plants, they can harness sunlight and convert it to energy-rich compounds. One type of algae, commonly called "Chlamy," is particularly noted for the energy-dense lipids it creates. And it is these lipids that, once harvested, can be readily converted to fuels.
But there's a catch. The Chlamy cells only generate these lipids when they're stressed, for example when denied certain nutrients like nitrogen or sulfur. Importantly, if researchers stress them too much, they can die. Obviously, it's hard to build a reliable energy platform around this problem.
“We know how to stress the algae,” reported Chew Yee Ngan of the DOE Joint Genome Institute, the study’s first author. “What we don’t know is how to keep the algae alive at the same time, until now.”
A New Breakthrough
In order to tackle this issue, scientists looked at what genes were being activated in stressed and non-stressed Chlamy cells. In particular, they analyzed the DNA and proteins found in the cell's chromatin, looking for transcription factors, or specific proteins that control the production of lipids.
"We’re looking for changes in starved cells vs. cells that are happily growing,” Ngan explained. Through the course of their experiments, one protein stood out. Known as PSR1, this transcription factor was found to trigger the cells to produce lipids.
“The study also demonstrated how cells can be tricked into producing lots of lipid without dying of starvation by overexpression of PSR1,” stated study co-author Axel Visel, DOE Joint Genome Institute Deputy for Science Programs.
This new information can now be used to develop more specific approaches to the production of algae lipids for biofuel. The potential is exciting. Once fully developed, fuel from algae could be used to power anything that currently runs on gasoline. Furthermore, algae requires carbon dioxide to grow, and would actually remove this greenhouse gas from the atmosphere.
WATCH: How Biofuels Are Extracted From Algae.