Table 2.
Reductase assays and kinetic constants
| Assay | Protein | Km[GSH], mM | Vmax, μmol⋅min−1⋅mg−1 |
|---|---|---|---|
| APS | APR1p | 0.6 | 0.18 |
| APR2p | 1.2* | 3.10 | |
| APR3p | 0.9* | 0.21 | |
| HED | APR1p | 1.2 | 21.2 |
| C | 1.2 | 60.5 | |
| R | NA | NA | |
| Cystine | APR1p | 1.2 | 41.1 |
| C | 1.1* | 54.3 | |
| R | NA | NA | |
| DHA | APR1p | 1.1* | 52.8 |
| C | 1.2* | 62.4 | |
| R | NA | NA |
Assay refers to the substrate reduced; Km[GSH] was measured at saturating level of the second substrate indicated in the assay column. Vmax is in μmol⋅min−1 per mg of protein; NA, no activity or unable to be calculated. All values were calculated from four independent data sets. ∗ indicates SD 10–20% of value; all others less than 10% of value.