Project description:Transcriptome analysis of Oleaginous microalgae from the Peruvian Amazon of the genus Ankistrodesmus, Chlorella, and Scenedesmus Transcriptome
Project description:The polysaccharide β-mannan, which is common in terrestrial plants but unknown in microalgae, was recently detected during diatom blooms. We identified a β-mannan polysaccharide utilization locus (PUL) in the genome of the marine Flavobacterium Muricauda sp. MAR_2010_75 which resembles PULs in bacteria from diverse ecosystems. Proteomics showed the β-mannan induced translation of 22 proteins encoded within the PUL.
Project description:Phytoplankton lipids, such as microalgae lipids, are important compounds of increasing interest in bioenergy, food, pharmacy, aquaculture and ecology for their high molecular diversity. There is a taxonomically diverse lipid response under P stress with unresolved questions related to the diversified mechanism behind the lipid responses. A marine microalgae with high EPA content was isolated, named Nannochloropsis sp. PJ12. We reveal a mechanism of phosphorus-induced lipid class remodeling in Nannochloropsis sp. PJ12 based on highly corresponding transcriptome and lipidome data. Phosphorus- deprivation leads to the rapid reduction of phospholipids (PL) and synthesis of the betaine lipids (BL). Phosphorus-complement recovers the content of PL and BL to the original level. The changes are mediated mainly by a glycerophosphoryldiester phosphodiesterases on the transcriptome level. To adapt to low phospholipids, the transcription levels of gene encoding P transporter were upregulated. When Nannochloropsis sp. PJ12 was once again under phosphorus-complement, some of gene encoding P transporter continue to increase on the transcription levels. The novel phospholipid-remodeling scheme opens new avenues for metabolic engineering of lipid composition in algae.
Project description:Limited systems-level understanding of CO2 concentrating mechanism (CCM) and metabolic adaption in response to different CO2-level in wild oleaginous algae has hindered the development of microalgal feedstock and the knowledge of its role in global warming and oceanic acidification. Nannochloropsis are a group of small unicellular microalgae widely distributed in oceans and fresh water, which implies that it plays a crucial role in biogeochemical cycles impinged on global climate change. In addition, Nannochloropsis has been used for flue gas fixation in many large-scale and pilot-scale outdoor cultivation facilities for photosynthetic production of fuels and chemicals. To untangle the intricate genome-wide networks underlying CCM and metabolic adjustment under different CO2 concentrations in Nannochloropsis, we applied high-throughput mRNA-sequencing and reconstructed the structure and dynamics of the genome-wide functional network underlying robust microalgal CCM and in Nannochloropsis oceanica, by tracking the genome-wide, single-base-resolution transcript change for the complete time-courses of different CO2 concentrations.