Botryococcus braunii Showa Transcriptome. Botryococcus braunii Showa

Amongst oleaginous eukaryotic algae, Botryococcus braunii Showa is unique in producing large amounts of liquid hydrocarbons of terpenoid origin. Biosynthetic engineering of terpenoid bio-crude production requires the identification of the genes and the reconstruction of the metabolic pathways responsible for the production of both the hydrocarbons and the other metabolites of the alga that compete for photosynthetic carbon and energy. A de novo assembly of 1,334,609 next-generation pyrosequencing reads afforded a transcriptomic database of 46,422 contigs with an average length of 756 bp. Contigs were annotated with pathway, ontology, and protein domain identifiers. Manual curation allowed the reconstruction of pathways that yield terpenoid storage hydrocarbons from primary metabolites, and pathways that divert photosynthetic carbon into tetraterpenoid carotenoids, diterpenoids, and the prenyl chains of meroterpenoid quinones and chlorophyll.