Table I.
Measurements of cell characteristics and enzyme activities
The measurements were done on C. reinhardtii cells cultured at low (air) levels of CO2, in the presence of 0.1, 1, or 10 mm NH4+. The values in parentheses indicate the sds obtained from the analysis of three cultures.
| Measurements
|
[NH4+] in the Growth Medium
|
||
|---|---|---|---|
| 0.1 mm | 1.0 mm | 10 mm | |
| Specific growth rate (d-1) | 0.14 (0.06) | 0.52 (0.02) | 0.54 (0.03) |
| Cell surface area (μm2) | 98.2 (18.2) | 113 (19.6) | 152 (9.13) |
| Cell volume (μm3) | 103 (24.7) | 126 (31.3) | 194 (16.6) |
| Total amino acids (fmol cell-1) | 0.13 (0.03) | 0.28 (0.06) | 0.21 (0.08) |
| Total protein (pg cell-1) | 16.8 (0.42) | 33.9 (4.02) | 45.7 (1.34) |
| Starch (pg cell-1) | 55.3 (1.17) | 12.1 (0.59) | 2.06 (0.54) |
| Chlorophyll a (pg cell-1) | 1.08 (0.02) | 3.12 (0.17) | 3.86 (0.41) |
| Chlorophyll b (pg cell-1) | 0.37 (0.03) | 1.17 (0.08) | 1.57 (0.00) |
| N (pg cell-1) | 1.61 (0.20) | 6.49 (0.24) | 8.52 (0.65) |
| C:N (mass ratio) | 12.0 (0.27) | 4.67 (0.05) | 4.80 (0.01) |
| pCA (WAU/106 cells) | 1.37 (0.49 | 6.86 (0.39) | 6.47 (0.30) |
| PEPc activity (fmol cell-1 h-1) | 4.13 (0.56) | 10.0 (2.12) | 22.5 (0.43) |
| PC activity (fmol cell-1 h-1) | 13.5 (2.76) | 43.7 (2.53) | 50.7 (1.53) |
| GS activity (fmol cell-1 h-1) | 0.59 (0.23) | 37.1 (2.65) | 44.8 (3.03) |
| Specific growth rate at 5% (v/v) CO2 (d-1) | 0.14 (0.06) | 0.73 (0.01) | 1.18 (0.02) |