Figure 3.

Uptake of HCO₃⁻ by high-CO₂-grown cells (H) of WT (▾) and the CMP+ mutant (○, ●) and low-CO₂-grown cells (▴) of WT (H) in the light. Cells were grown with NH₄⁺ (○) or NO₃⁻ (●, ▾, ▴) as the nitrogen source. Uptake was initiated by illumination immediately after the addition of 100 μM H¹⁴CO₃⁻ to the cell suspensions. The amount of HCO₃⁻ taken up by the cells was determined from the total amount of ¹⁴C accumulated in the cell. Assays were done at 30°C and pH 9.0.