Table 1 Effects of FXN and ISCU on the single turnover kinetic parameters.
From: Mammalian frataxin directly enhances sulfur transfer of NFS1 persulfide to both ISCU and free thiols
Proteins and complexes | Reductant |
| kT (s−1) |
|
|---|---|---|---|---|
NI | DTT | 2.9±0.5 | NA | NA |
NI+F | DTT | 2.9±0.5 | NA | NA |
NIU | DTT | 0.6±0.2 | 0.0017±0.0002 | 0.23±0.1 |
NIUF | DTT | 14±4 | >0.09* | 0.30±0.1 |
NIUF | GSH | 0.1±0.05 | >0.09* | ≈ 0 |
(M−1 s−1)
(M−1 s−1)- DTT, dithiothreitol; FXN, frataxin; GSH, glutathione; NA, not applicable.
, kT and 
represent the rate constants of NFS1 persulfide reduction, NFS1 persulfide transfer to ISCU and ISCU persulfide reduction, respectively, determined using maleimide-peptide assays. Each data set was fitted using second-order and first-order rate equations for reduction and transfer, respectively (see Methods). The values represent the mean of three independent experiments with associated s.e.- *Indicate the minimum value that can be determined in that case using the maleimide-peptide assay.
, kT and 
represent the rate constants of NFS1 persulfide reduction, NFS1 persulfide transfer to ISCU and ISCU persulfide reduction, respectively, determined using maleimide-peptide assays. Each data set was fitted using second-order and first-order rate equations for reduction and transfer, respectively (see Methods). The values represent the mean of three independent experiments with associated s.e.