Table 1.
DNA-binding and glutathione-binding affinities of PrfA
| DNA-binding affinity (Kd ± s.e.m.) | ||
|---|---|---|
|
| ||
| Phly (nM) | PactA (nM) | |
| Wild type (oxidized) | 888.5 ± 140.3 | ND |
| Wild type (reduced) | 34.2 ± 4.9 | 96.4 ± 7.3 |
| PrfA(C/A)4 | 32.8 ± 5.5 | 124.9 ± 26.3 |
| PrfA* | 40.8 ± 3.3 | 45.4 ± 3.2 |
| Glutathione-binding affinity (Kd ± s.e.m.) | ||
|---|---|---|
|
| ||
| GSH (mM) | GSSG (mM) | |
| Wild type | 4.37 ± 1.2 | NBD |
| PrfA(C/A)4 | 4.74 ± 1.5 | NBD |
DNA-binding affinity for the hly promoter (Phly) and the actA promoter (PactA), as measured by fluorescence anisotropy, and glutathione-binding affinity, as measured by bio-layer interferometry. The affinity of oxidized PrfA to PactA was not determined (ND). DNA-binding affinities of PrfA(C/A)4 and PrfA* were unaffected by oxidation. For oxidized glutathione (GSSG) no measurable binding was detected (NBD).