Fig. 2.

Growth curve of the main batch culture without bubbling or shaking and the time course of photosynthetic ¹⁴C fixation in the coccolithophorid Emiliania huxleyi NIES837. a Algal growth curve of the main culture. The culture (500 ml) was maintained under continuous illumination at 120 μmol photons m⁻² s⁻². At the logarithmic (LP cells) and stationary (SP cells) growth phases, an aliquot (100 ml) of the culture was transferred to a fresh subculture flask for ¹⁴C labeling. b Time courses of changes in ¹⁴C remaining in the medium (open symbols) and ¹⁴C incorporated into cells (closed symbols) in LP (diamonds) and SP cells (triangles). c Time courses of ¹⁴C fixation (calculated as dpm per cell) for LP cells (closed diamonds) and SP cells (closed triangles). The photosynthetic rates were 0.13 and 0.05 dpm cell⁻¹ h⁻¹ in LP and SP cells, respectively. Values are means ± SD of three independent experiments. For details of ¹⁴C-labeling experiments, see the “Materials and Methods.” The temperature was maintained at 20 °C during both culture (a) and ¹⁴C-labeling (b, c)