Table 4.
Parameters of PSI Activity Obtained from P700+ Absorption Measurements on Mutant and Wild-Type (Col-0 and Ws-2) Plants
| Pm | Y(I) | Y(ND) | Y(NA) | |
|---|---|---|---|---|
| Col-0 | 0.27 ± 0.03 | 0.67 ± 0.05 | 0.22 ± 0.03 | 0.11 ± 0.01 |
| Ws-2 | 0.29 ± 0.03 | 0.68 ± 0.06 | 0.20 ± 0.02 | 0.12 ± 0.01 |
| stn7-1 | 0.25 ± 0.03 | 0.66 ± 0.04 | 0.18 ± 0.02 | 0.16 ± 0.02 |
| stn8-1 | 0.27 ± 0.01 | 0.67 ± 0.03 | 0.21 ± 0.01 | 0,12 ± 0.01 |
| psal-1 | 0.25 ± 0.02 | 0.62 ± 0.04 | 0.20 ± 0.02 | 0.18 ± 0.02 |
| pete2-1.1 | 0.25 ± 0.01 | 0.59 ± 0.02 | 0.33 ± 0.01 | 0.08 ± 0.01 |
| psae1-3 | 0.12 ± 0.02 | 0.54 ± 0.03 | 0.07 ± 0,01 | 0.39 ± 0.03 |
| psad1-1 | 0.11 ± 0.01 | 0.51 ± 0.03 | 0.08 ± 0.01 | 0.41 ± 0.03 |
| stn7-1 pete2-1.1 | 0.25 ± 0.03 | 0.53 ± 0.02 | 0.24 ± 0.02 | 0.23 ± 0.01 |
| stn7 psad1-1 | 0.11 ± 0.00 | 0.42 ± 0.03 | 0.04 ± 0.00 | 0.54 ± 0.04 |
| stn7 psae1-3 | 0.12 ± 0.01 | 0.45 ± 0.02 | 0.04 ± 0.00 | 0.51 ± 0.03 |
| psal-1 pete2-1 | 0.26 ± 0.01 | 0.55 ± 0.01 | 0.27 ± 0.00 | 0.18 ± 0.01 |
| psal-1 psad1-1 | 0.10 ± 0.01 | 0.46 ± 0.02 | 0.06 ± 0.01 | 0.48 ± 0.02 |
| psal-1 psae1-3 | 0.13 ± 0.01 | 0.48 ± 0.05 | 0.06 ± 0.00 | 0.46 ± 0.04 |
| stn8 pete2-1 | 0.24 ± 0.00 | 0.58 ± 0.01 | 0.34 ± 0.01 | 0.08 ± 0.01 |
| stn8 psad1-1 | 0.12 ± 0.01 | 0.52 ± 0.03 | 0.08 ± 0.01 | 0.40 ± 0.01 |
| stn8 psae1-3 | 0.12 ± 0.00 | 0.55 ± 0.03 | 0.09 ± 0,01 | 0.36 ± 0.01 |
Measurements were performed as described in Methods. Mean values for five plants (±sd) are shown. Pm, the maximal change of the P700 signal upon quantitative transformation of P700 from the fully reduced to the fully oxidized state; Y(I), the photochemical quantum yield of PSI; Y(ND), the fraction of overall P700 that is oxidized in a given state (provides a measure of PSI donor side limitation); Y(NA), the fraction of overall P700 that cannot be oxidized by a saturation pulse in a given state (provides a measure of PSI acceptor side limitation). For further details, see Methods.