Breakthrough Discovery Reveals Key Biofuel-Producing Alga Is Actually Three Distinct Species

A study by Texas A&M AgriLife researchers has unveiled that Botryococcus braunii, long believed to be a single species, is actually three distinct species. This discovery could significantly impact the future of biofuel production.

In a groundbreaking study, a team of researchers led by former doctoral student Devon Boland from Texas A&M AgriLife has discovered that a vital biofuel-producing microalga, long presumed to be a single species with three chemical races, is actually three separate species. This revelation has significant implications for renewable energy and biofuel production.

The microalga in question, Botryococcus braunii, has been studied for its ability to produce high quantities of hydrocarbons, which can be used as a renewable fuel source. The species was initially classified with three races – A, B and L – each producing different types of oils. However, Boland’s research revealed substantial genetic differences between these races.

“You start to think that must be right. No one has found otherwise, and all those scientists have had much longer careers than me — I’m just a kid,” Boland, who is currently an assistant research scientist in the Department of Whole Systems Genomics Initiative at Texas A&M, said in a news release. “But I ended up getting to propose names for a species that were accepted for publication, which is something I never thought would happen.”

This new classification arose from necessity. When the COVID-19 pandemic shut down lab access, Boland and his adviser Tim Devarenne, associate head of undergraduate programs and associate professor in the Department of Biochemistry and Biophysics at the Texas A&M College of Agriculture and Life Sciences, shifted their focus to genetic data and bioinformatics.

Using genomic sequencing, the team found a 20-30% genetic difference between the races. To put this in perspective, the genetic variance between humans and chimpanzees is less than 2%.

“Having the genome of your organism of interest mapped out is always ideal in research because it allows you to more easily find genes and work to determine their functions,” Devarenne said in the news release.

The research team, including Daniel Browne, Ivette Cornejo Corona and John Mullet from Texas A&M and international collaborator Shigeru Okada, worked extensively to piece together the genomes. They utilized the high-performance supercomputing resources at Texas A&M to run comparative analyses, which confirmed the substantial differences between the races.

“It was like everywhere we looked, things were different,” Boland added.

Ultimately, the research resulted in the reclassification of the Botryococcus races. Race B retained the name Botryococcus braunii, while races A and L were renamed to Botryococcus alkenealis and Botryococcus lycopadienor, respectively. These names reflect the specific hydrocarbons each produces.

Devarenne emphasized the broader importance of this reclassification for the scientific community.

“How we define separate species might not change much with how these organisms are used in research,” Devarenne added. “But it’s important for the scientific understanding, how we think about the ways these organisms are related to each other and to all other species.”

The team’s work, published in the open-access journal PLOS One, ensures that their findings are accessible to other researchers who can build on their discoveries. The complete genomes of the newly classified species are also available on the National Center for Biotechnology Information website.

“It was important to us that the information was publicly available when it was ready to publish,” Boland added. “Science is community driven. The ultimate goal is always to further our collective knowledge, and I think that’s what we accomplished here.”