Table I.
Kinetic parameters for pAtDEF1 and 2 with two spectrophotometric assays for peptide deformylase activity
| Protein Source/Substrate Used | Vmax | Apparent Km | Kcat | Kcat/Km |
|---|---|---|---|---|
| μmols min−1 mg protein−1 ± se | μm ± se | s−1 | m−1 s−1 | |
| pAtDEF1 | ||||
| f-MLρ-NA | 0.11 ± 0.01 | 240 ± 34 | 0.044 | 1.8 × 102 |
| f-MAS | 0.20 ± 0.01 | 710 ± 120 | 0.078 | 1.1 × 102 |
| pAtDEF2 | ||||
| f-MLρ-NA | 20 ± 0.3 | 130 ± 4 | 8.7 | 6.8 × 104 |
| f-MAS | 1.3 ± 0.1 | 3,200 ± 370 | 0.54 | 1.7 × 102 |
| E. coli | ||||
| f-MLρ-NAa | – | 20.3 | 38 | 1.9 × 106 |
| f-MASb | – | 3,900 | 210 | 5.4 × 104 |
f-MLρ-NA, N-formyl-Met-Leu-ρ-nitroanilide substrate coupled with Aeromonas proteolytica aminopeptidase. f-MAS, N-formyl-Met-Ala-Ser substrate coupled with β-NAD+ and yeast formate dehydrogenase.