0000000000365759
AUTHOR
Dipali Singh
Supplementary Fig. 4 A Respiration and photosynthesis in P. tricornutum cells from Investigating mixotrophic metabolism in the model diatom Phaeodactylum tricornutum.
Direct assessment of oxygen consumption by a polarographic approach in both phototrophy (black bar) and mix-otrophy (red bar). B. Fluorescent based-assay to monitoring the changes in respiration using the Redox Dye A in presence of the selected compounds (see methods).
Supplementary Fig. 1 Quantitative analysis of P. tricornutum glycerolipids from Investigating mixotrophic metabolism in the model diatom Phaeodactylum tricornutum.
TAG profile in a total lipid extract from cells grown in replete conditions (A) and deplete conditions (B) in both mixotrophic and phototrophic mode. Glycerolipids are expressed in nmol / mg of dry cells. Each result is the average of two biological replicates ± SD. PHOT: light in N-replete condition; PHOTO-N: light in N-deplete condi-tion; MIX: light+glycerol in N-replete condition; MIX-N: light+glycerol in N-deplete condition.
Supplementary Fig. 2 Membrane lipid composition in P. tricornutum from Investigating mixotrophic metabolism in the model diatom Phaeodactylum tricornutum.
Lipid analysis of cells grow in N-replete conditions and N-deplete conditions in both mixotrophic and phototrophic mode. Each result is the average of two biological replicates ± SD. SQDG, sulfoquinovosyldiacylglycerol; DGDG, digalactosyldiacylglycerol; MGDG, monogalactosyldiacylglycerol; PC, phosphatidylcholine; PHOT: light in N-replete condition; PHOTO-N: light in N-deplete condition; MIX: light+glycerol in N-replete condition; MIX-N: light+glycerol in N-deplete condition.
A systems-wide understanding of photosynthetic acclimation in algae and higher plants
The ability of phototrophs to colonise different environments relies on robust protection against oxidative stress, a critical requirement for the successful evolutionary transition from water to land. Photosynthetic organisms have developed numerous strategies to adapt their photosynthetic apparatus to changing light conditions in order to optimise their photosynthetic yield, which is crucial for life on Earth to exist. Photosynthetic acclimation is an excellent example of the complexity of biological systems, where highly diverse processes, ranging from electron excitation over protein protonation to enzymatic processes coupling ion gradients with biosynthetic activity, interact on drasti…
Investigating mixotrophic metabolism in the model diatom Phaeodactylum tricornutum.
Diatoms are prominent marine microalgae, interesting not only from an ecological point of view, but also for their possible use in biotechnology applications. They can be cultivated in phototrophic conditions, using sunlight as the sole energy source. Some diatoms, however, can also grow in a mixotrophic mode, wherein both light and external reduced carbon contribute to biomass accumulation. In this study, we investigated the consequences of mixotrophy on the growth and metabolism of the pennate diatom Phaeodactylum tricornutum , using glycerol as the source of reduced carbon. Transcriptomics, metabolomics, metabolic modelling and physiological data combine to indicate that glycerol affect…
Supplementary Fig. 3 Quantification of intracellular pyruvate by a fluorescence-based method from Investigating mixotrophic metabolism in the model diatom Phaeodactylum tricornutum
A. Pyruvate standard curve. B. Quantification of intracellular pyruvate in cells grown in phototrophy (PHOT) and mixotrophy (MIX).
Boosting Biomass Quantity and Quality by Improved Mixotrophic Culture of the Diatom Phaeodactylum tricornutum
Diatoms are photoautotrophic unicellular algae and are among the most abundant, adaptable, and diverse marine phytoplankton. They are extremely interesting not only for their ecological role but also as potential feedstocks for sustainable biofuels and high-value commodities such as omega fatty acids, because of their capacity to accumulate lipids. However, the cultivation of microalgae on an industrial scale requires higher cell densities and lipid accumulation than those found in nature to make the process economically viable. One of the known ways to induce lipid accumulation in Phaeodactylum tricornutum is nitrogen deprivation, which comes at the expense of growth inhibition and lower c…
Supplementary Fig. 5 Screening of mixotrophic efficiency by biolog and redox dye assay in P. tricornutum from Investigating mixotrophic metabolism in the model diatom Phaeodactylum tricornutum.
A. OD750 nm changes (relative to phototrophic growth) of P. tricornutum cells grown for 6 days in BiologTM plates P1 and PM2A that contains 190 carbon compounds (see methods). Each data point represents a different com-pound. B. Growth profile of P. tricornutum on few selected compounds (at 20 mM) and a phototrophic control in 100 mL flasks. C. Areas under the growth curves of Supplementary Fig. 5B normalized to the area of the curve of phototrophic growth.