TABLE 2.
Catalytic properties of 2-phenanthroate:CoA ligase from culture TRIP and the purified recombinant enzyme from E. colia
| Parameter | Specific activity of phenanthroate:CoA ligase (nmol min−1 mg−1) |
|
|---|---|---|
| Cell-free extract | Heterologously expressed | |
| Substrate | ||
| 1 mM 2-phenanthroic acid | 2,482 ± 526 | 180.4 ± 30.8 |
| 1 mM 3-phenanthroic acid | 518 ± 89 | 2.4 ± 0.19 |
| 1 mM 4-phenanthroic acid | 27 ± 1 | ND |
| 1 mM 1-phenanthroic acid | 22 ± 5 | ND |
| 1 mM 9-phenanthroic acid | 0 | ND |
| Nucleotide | ||
| 5 mM ADP | 5,783 ± 1,279 | 152.1 ± 26.7 |
| 5 mM ATP | 4,914 ± 303 | 203.8 ± 15.9 |
| 5 mM CTP | 2,578 ± 1,262 | 2.1 ± 0.1 |
| 5 mM UTP | 1,192 ± 880 | 0.67 ± 0.08 |
| 5 mM GTP | 739 ± 186 | 0.6 ± 0.09 |
| Without nucleotides | 170 ± 136 | 0 |
a
ND, not detected. The values represent the mean and variance of three replicate enzyme assays.