Seawater carbonate chemistry and photosynthetic pigments and photophysiology of polar microalga Chlorella sp.

• Main Authors: Tan, Yong Hao, Lim, Phaik Eem, Beardall, John, Poong, Sze Wan, Phang, Siew Moi
• Format: Dataset
• Language: English
• Published: PANGAEA 2019
• Subjects: Alkalinity; total; standard deviation; Aragonite saturation state; Bicarbonate ion; Bottles or small containers/Aquaria (<20 L); Calcite saturation state; Calculated using CO2SYS; Calculated using seacarb after Nisumaa et al. (2010); Carbon; inorganic; dissolved; Carbonate ion; Carbonate system computation flag; Carbon dioxide; Carotenoids; Carotenoids per cell; Cell biovolume; Cell density; Cell surface area/cell volume; Cell surface area/cell volume ratio; Chlorella sp.; Chlorophyll a; Chlorophyll a per cell; Chlorophyta; Day of experiment; Diameter; Fugacity of carbon dioxide (water) at sea surface temperature (wet air); Growth/Morphology; Growth rate; Laboratory experiment; Laboratory strains; Antarc*; Antarctic; Ocean acidification
• Online Access: https://doi.pangaea.de/10.1594/PANGAEA.916160; https://doi.org/10.1594/PANGAEA.916160

Ocean acidification, due to increased levels of anthropogenic carbon dioxide, is known to affect the physiology and growth of marine phytoplankton, especially in polar regions. However, the effect of acidification or carbonation on cellular metabolism in polar marine phytoplankton still remains an open question. There is some evidence that small chlorophytes may benefit more than other taxa of phytoplankton. To understand further how green polar picoplankton could acclimate to high oceanic CO2, studies were conducted on an Antarctic Chlorella sp. Chlorella sp. maintained its growth rate (∼0.180 /day), photosynthetic quantum yield (Fv/Fm = ∼0.69) and chlorophyll a (0.145 fg/cell) and carotenoid (0.06 fg/cell) contents under high CO2, while maximum rates of electron transport decreased and non-photochemical quenching increased under elevated CO2. GCMS-based metabolomic analysis reveal that this polar Chlorella strain modulated the levels of metabolites associated with energy, amino acid, fatty acid and carbohydrate production, which could favour its survival in an increasingly acidified ocean.