TABLE 1.
Summary of the purification of recombinant NerA
| Purification stepa | Total vol (ml) | Protein concn (mg/ml) | Total protein (mg) | Enzyme activity (U/ml) | Total enzyme activity (U) | Sp act (U/mg) | Yield (%) | Purification (n-fold) |
|---|---|---|---|---|---|---|---|---|
| Cell extract | 65 | 7.24 | 471 | 6.35 | 413 | 0.88 | 100 | 1 |
| Affinity chromatography | 37 | 3.70 | 137 | 7.07 | 262 | 1.91 | 63 | 2.2 |
| Ion-exchange chromatography | 8.5 | 7.14 | 60.7 | 21.4 | 182 | 2.99 | 44 | 3.4 |
| HIC peak 1 | 27.5 | 0.82 | 22.6 | 2.52 | 69.3 | 3.07 | 17 | 3.5 |
| HIC peak 2 | 20 | 0.85 | 17.0 | 0.001 | 0.02 | 0.001 | —b | —b |
a
HIC, hydrophobic-interaction chromatography.
b
This fraction is the protein lacking FMN and therefore lacking enzyme activity (see text).