The nitrogen costs of photosynthesis in a diatom under current and future pCO2, supplement to: Li, Gang; Brown, Christopher M; Jeans, Jennifer A; Donaher, Natalie A; McCarthy, Avery; Campbell, Douglas A (2015): The nitrogen costs of photosynthesis in a diatom under current and future pCO2. New Phytologist, 205(2), 533-543

• Main Authors: Li, Gang, Brown, Christopher M, Jeans, Jennifer A, Donaher, Natalie A, McCarthy, Avery, Campbell, Douglas A
• Format: Dataset
• Language: English
• Published: PANGAEA - Data Publisher for Earth & Environmental Science 2015
• Subjects: Biomass/Abundance/Elemental composition; Bottles or small containers/Aquaria <20 L; Chromista; Growth/Morphology; Laboratory experiment; Laboratory strains; Light; Not applicable; Ochrophyta; Pelagos; Phytoplankton; Primary production/Photosynthesis; Single species; Thalassiosira pseudonana; Species; Irradiance; Treatment; Growth rate; Identification; Cell biovolume; Protein per cell; Nitrogen content per cell; Chlorophyll a per cell; Ratio; Chlorophyll c per cell; Fucoxanthin chlorophyll protein per cell; Photosynthetic protein PsbC; Photosynthetic protein PsbA; Photosynthetic protein PsbD; Photosynthetic protein Rubisco; Cytochrome c1; Temperature, water; Salinity; Carbon, inorganic, dissolved; pH; Partial pressure of carbon dioxide water at sea surface temperature wet air; Alkalinity, total; Bicarbonate ion; Carbonate ion; Carbon dioxide; Phosphate; Silicate; Carbonate system computation flag; Fugacity of carbon dioxide water at sea surface temperature wet air; Aragonite saturation state; Calcite saturation state; Potentiometric; Calculated using CO2SYS; Calculated using seacarb after Nisumaa et al. 2010; Ocean Acidification International Coordination Centre OA-ICC; Avery; McCarthy; Ocean acidification
• Online Access: https://dx.doi.org/10.1594/pangaea.847792; https://doi.pangaea.de/10.1594/PANGAEA.847792

With each cellular generation, oxygenic photoautotrophs must accumulate abundant protein complexes that mediate light capture, photosynthetic electron transport and carbon fixation. In addition to this net synthesis, oxygenic photoautotrophs must counter the light-dependent photoinactivation of Photosystem II (PSII), using metabolically expensive proteolysis, disassembly, resynthesis and re-assembly of protein subunits. We used growth rates, elemental analyses and protein quantitations to estimate the nitrogen (N) metabolism costs to both accumulate the photosynthetic system and to maintain PSII function in the diatom Thalassiosira pseudonana, growing at two pCO2 levels across a range of light levels. The photosynthetic system contains c. 15-25% of total cellular N. Under low growth light, N (re)cycling through PSII repair is only c. 1% of the cellular N assimilation rate. As growth light increases to inhibitory levels, N metabolite cycling through PSII repair increases to c. 14% of the cellular N assimilation rate. Cells growing under the assumed future 750 ppmv pCO2 show higher growth rates under optimal light, coinciding with a lowered N metabolic cost to maintain photosynthesis, but then suffer greater photoinhibition of growth under excess light, coincident with rising costs to maintain photosynthesis. We predict this quantitative trait response to light will vary across taxa. : In order to allow full comparability with other ocean acidification data sets, the R package seacarb (Gattuso et al, 2015) was used to compute a complete and consistent set of carbonate system variables, as described by Nisumaa et al. (2010). In this dataset the original values were archived in addition with the recalculated parameters (see related PI). The date of carbonate chemistry calculation is 2015-07-03.