Table 3.
Equilibrium and kinetics parameters for DNA binding and dissociation upon oxidation for SqrR C9S.
| Keq [x 105 M−1]a | kox [x 10−3 s−1]a | ||
|---|---|---|---|
| GSSH | CSSH | ||
| SqrR reduced | 270 ± 25 (n = 6) | 0.86 ± 0.05 (n = 3) | 3.8 ± 0.1(n = 3) |
| SqrR, GSSH treated | 2.5 ± 0.5 (n = 3) | — | — |
| SqrR, CysSSH treated | 1.8 ± 0.8 (n = 3) | — | — |
a
Errors correspond to standard deviations of the mean for n number of experiments carried out under the same conditions: 25 mM HEPES, pH = 7.0, 400 mM NaCl, 1 mM EDTA, 25°C. The treatment with GSSH or CysSSH corresponds to a 20-fold addition of sulfane sulfur relative to the protein subunit concentration.