Table 2.
Na+-Dependent Glutamate Transport inSynechocystis sp. Strain PCC 6803 and gltS andgtr Mutants
| Strain | Genotype | Glutamate uptake (nmol · mg Chl−1) | |||
| 16 mM NaCl | 46 mM NaCl | ||||
| PCC 6803 | Wild type | 271 ± 99 | 301 ± 86 | ||
| CSMJ6 | gltS (slr1145) | 164 ± 39 | 184 ± 50 | ||
| CSX67 | gtrAB (sll1102/sll1103) | 198 ± 57 | 212 ± 39 | ||
| CSX68 | gtrC (sll1104) | 203 ± 47 | 243 ± 66 | ||
| CSMJ20 | gltS gtrAB (slr1145 sll1102/sll1103) | 151 ± 51 | 160 ± 40 | ||
| CSMJ22 | gltS gtrC (slr1145 sll1104) | 107 ± 28 | 131 ± 39 | ||
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↵The assays were performed for 10 min with 10 μM [14C]glutamate in 25 mM Tricine-KOH (pH 8.1) buffer supplemented with the indicated NaCl concentrations. The figures shown are the mean and standard deviation of the data from four or five independent experiments. With no added NaCl, activities were ∼15 nmol · mg Chl−1 for the wild type and negligible for the mutants.
