Culture conditions, mass spectrometric measurements and acclimation carbonate chemistry ...

• Main Authors: Kottmeier, Dorothee, Rokitta, Sebastian D, Rost, Björn
• Format: Dataset
• Language: English
• Published: PANGAEA 2016
• Subjects: Phytochange @ AWI AWI_Phytochange; Ocean acidification
• Online Access: https://dx.doi.org/10.1594/pangaea.859864; https://doi.pangaea.de/10.1594/PANGAEA.859864

- A combined increase in seawater [CO2] and [H+] was recently shown to induce a shift from photosynthetic HCO3- to CO2 uptake in Emiliania huxleyi. This shift occurred within minutes, whereas acclimation to ocean acidification (OA) did not affect the carbon source.- To identify the driver of this shift, we exposed low- and high-light acclimated E. huxleyi to a matrix of two levels of dissolved inorganic carbon (1400, 2800 lmol kg-1) and pH (8.15, 7.85) and directly measured cellular O2, CO2 and HCO3 fluxes under these conditions.- Exposure to increased [CO2] had little effect on the photosynthetic fluxes, whereas increased [H+] led to a significant decline in HCO3- uptake. Low-light acclimated cells overcompensated for the inhibition of HCO3- uptake by increasing CO2 uptake. High-light acclimated cells, relying on higher proportions of HCO3- uptake, could not increase CO2 uptake and photosynthetic O2 evolution consequently became carbon-limited.- These regulations indicate that OA responses in photosynthesis ... : Supplement to: Kottmeier, Dorothee; Rokitta, Sebastian D; Rost, Björn (2016): Acidification, not carbonation, is the major regulator of carbon fluxes in the coccolithophore Emiliania huxleyi. New Phytologist, 211(1), 126-137 ...