Table 1.
Key parameter values used in the numerical simulation of the CCM in Trichodesmium
| Variable | Units | Model value |
|---|---|---|
| Cell radius, Rb | µm | 3 |
| Carboxysome radius, Rc | µm | 0.15 |
| Rubisco reaction rate, kRub | s–1 per active site | 1.92 |
| Rubisco KCO2 | µM | 145 |
| Rubisco KO2 | µM | 600 |
| Rubisco specificity, S | – | 45 |
| Number of Rubisco active sites | – | 54000 |
| Number of carbonic anhydrase active sites | – | 900 |
| Carbonic anhydrase half-maximum constant for CO2, Kca | µM | 104.7 |
| Internal pH | – | 8.3 |
| pKaeff for HCO3–:CO2 | – | 5.84 |
| Carboxysome permeability | cm s–1 | 3 × 10–5 |
| HCO3– uptake velocity, jc | cm s–1 | 2.4 × 10–7 |
| CO2 to HCO3– conversion at membrane | cm s–1 | 0.6 × 10–7 |
The cell radius was measured from a bioimage collected using fluorescence microscopy (Supplementary Fig. S12). Kinetic constants of Rubisco carboxylation (KCO2), oxygenation (KO2), and the specificity factor (S) for a form 1B cyanobacteria were taken from Badger et al. (1998).