Carbon and nitrogen fluxes in the marine coccolithophore Emiliania huxleyi grown under different nitrate concentrations
نویسندگان
چکیده
a r t i c l e i n f o Information on interaction of C and N at the cellular level is lacking for ecologically relevant phytoplankton species. We examined the effects of NO 3-availability on C and N fluxes in the widely distributed marine coccolithophore Emiliania huxleyi. Cells were cultured at replete (∼280 μM) and ambient (∼10 μM) NO 3-, the latter representing a typical surface water nitrate concentration of the North Atlantic Ocean during spring. While growth rates and C to N ratios were not altered by the NO 3-availability, organic C and N as well as inorganic C quotas were reduced under ambient NO 3-. Growth at ambient NO 3-caused a higher proportion of fixed C to be allocated to lipids relative to carbohydrates and especially to proteins. Ambient NO 3-grown cells showed lower V max of nitrate reductase (NR) and nitrite reductase (NiR) (ambient/replete: V max NR = 0.64/1.09 fmol min-1 cell-1
منابع مشابه
Interactive comment on “Influence of CO2 and nitrogen limitation on the coccolith volume of Emiliania huxleyi (Haptophyta)” by M. N. Müller et al
The authors report on experimental results of the coccolithophore Emiliania huxleyi that was grown under nutrient replete (+N) and nitrogen limited (-N) conditions, both under a similar range of pCO2 levels / CO2 concentrations in the culture media. Each set of experiments was subjected to three concentrations of CO2 (corresponding to a "preindustrial" lower-than-modern pCO2 of ∼200-280 μatm, a...
متن کاملInteractive comment on “Influence of CO2 and nitrogen limitation on the coccolith volume of Emiliania huxleyi (Haptophyta)” by M. N. Müller et al
The authors report on experimental results of the coccolithophore Emiliania huxleyi that was grown under nutrient replete (+N) and nitrogen limited (-N) conditions, both under a similar range of pCO2 levels / CO2 concentrations in the culture media. Each set of experiments was subjected to three concentrations of CO2 (corresponding to a "preindustrial" lower-than-modern pCO2 of ∼200-280 μatm, a...
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