In a recent article for Redorbit Knowledge Network (a science and technology news source), Robert Burns of Texas AgriLife Research informs readers that the genome of Botryococcus braunii, an algae source for biofuel, is being sequenced by DOE’s Joint Genome Institute. Methods and results of the study will be published this summer in the journal of phycology. Dr. Timothy Devarenne and other scientists at AgriLife Research, the University of Tokyo, and the University of Kentucky have been studying this species of algae and focusing specifically on its genetic sequence. They found that Botryococcus braunii has 166.2 (± 2.2) base pairs; mice and men have 3 billion and 3.1 billion base pairs respectively according to Devarenne, so this species of algae has a relatively small genome. However, six other species of green algae have already been sequenced and all have an even smaller genome. The particular genome sequenced of the B race (two other races of Botryococcus braunii exist, but they were not dealt with in the study). The phylogeny of Botryococcus braunii was also examined in the study. Devarenne and the other scientists isolated genes from pure culture by using reverse transcription. The genes were mapped to confirm phylogenetic placement.
Botryococcus braunii holds special interest as a sustainable (or perhaps more accurately, renewable) fuel source. Producing hydrocarbon oil from algae is a relatively easy operation now. What all of these algae have in common as a fuel source is that large quantities of oil can be produced in a small area of land. Most green algae that are used for this purpose, however, produce vegetable oils. However, Botryococcus braunii produces hydrocarbons that are exactly the same as the ones in petroleum based fuels such as gasoline, kerosene, and diesel. Because of this, Devarenne claims that Botryococcus braunii is not technically a biofuel source, but is instead just a fuel source. His argument is furthered by the fact that many coal and oil sources contain oil from this species of algae. Like many other algae, Botryococcus braunii is capable of accumulating 86% of its dry weight in hydrocarbons. The greatest problem with Botryococcus braunii as a fuel source is that it takes about 4 days to double its growth, while other algae species take 6 to 12 hours.