Table I.
The difference in isotopic composition between oxygen evolved in photosynthesis by Synechocystis and the source water
The Δflv3 mutant unable to perform photoreduction of O2 was maintained under high CO2 level to eliminate O2 uptake by photorespiration. Note that the data provided for each difference (between the composition in evolving O2 gas and the substrate water) are based on three separate collections and isotopic measurements of O2 evolved (in the gas phase) and two determinations of O2 produced by fluorination of water.
| Experiment No. | δ18O Difference | 17Δ Difference |
|---|---|---|
| ‰ | per meg | |
| 1 | 0.59 ± 0.05 | 11 ± 8 |
| 2 | 0.54 ± 0.07 | 9 ± 8 |
| 3 | 0.27 ± 0.09 | 6 ± 6 |