ABSTRACT: Transcriptome analysis of Oleaginous microalgae from the Peruvian Amazon of the genus Ankistrodesmus, Chlorella, and Scenedesmus Transcriptome
Project description:We demonstrate that low-dose ionizing radiation from X-rays drives metabolic activation in microalgae. We exploited this phenomenon to develop a method for increased lipid yield in stationary phase Chlorella sorokiniana cultures by 25% in just 24 hours, caused by a reproducible metabolic response that includes up-regulation of >30 lipid metabolism genes. This approach avoids the need to modify the strain or cultivation conditions, and does not affect cell viability or biomass.
Project description:The microalga Coccomyxa subellipsoidea C-169 possesses some features that may be valuable for lipid production, and, as demonstrated in this study, can be greatly induced to produce a high amount of fatty acid by CO2 supplementation. Here we have compared the transcriptome of air group (AG, cells cultured under 0.04% CO2) and CO2-supplemented group (CG, cells cultured under 2% CO2), and found that dramatic and collaborative regulation in central metabolic pathways as well as biochemical processes occured in response to CO2 supplementation. This study gains a broad understanding of how CO2 stress regulates gene expression and eventually reveals a fine-tuned strategy adopted by C-169 to sustain rapid cell growth and lipid production, which will be helpful for the implementation of biofuels production from oleaginous microalgae. Transcriptomic profiles of Coccomyxa subellipsoidea C-169 cultured for 4 days under two CO2 levels (0.04% and 2%, v/v) were generated by digital gene expression (DGE) analysis, in triplicate, using Illumina Hiseq2000.
Project description:The microalga Coccomyxa subellipsoidea C-169 possesses some features that may be valuable for lipid production, and, as demonstrated in this study, can be greatly induced to produce a high amount of fatty acid by CO2 supplementation. Here we have compared the transcriptome of air group (AG, cells cultured under 0.04% CO2) and CO2-supplemented group (CG, cells cultured under 2% CO2), and found that dramatic and collaborative regulation in central metabolic pathways as well as biochemical processes occured in response to CO2 supplementation. This study gains a broad understanding of how CO2 stress regulates gene expression and eventually reveals a fine-tuned strategy adopted by C-169 to sustain rapid cell growth and lipid production, which will be helpful for the implementation of biofuels production from oleaginous microalgae.
Project description:Nitrogen limitation is a major regulator to initiate lipid overproduction in oleaginous fungi. To examine the influence of nitrogen starvation, chemiostat cultures of R. toruloides in defined media with abundant ammonium (MM) or minute ammonium (MM-N) were performed to obtain steady-state samples. Then Illumina's digital gene expression (DGE) technology was used for high-throughput transcriptome profiling of these samples.