TABLE 1.
Induction of β-galactosidase expression in P. putida S12(pKRZ-srp) by solvents
| Chemical | Concn (mM) | β-Galactosidase activitya (nmol min−1 mg of protein−1) | Induction (fold) |
|---|---|---|---|
| None | 3.8 ± 0.1 | 1.0 | |
| Aromatic solvents | |||
| Toluene | 1.0 | 13.3 ± 0.4 | 3.5 |
| 2.0 | 36.5 ± 0.6 | 9.6 | |
| 3.0 | 48.6 ± 5.4 | 12.8 | |
| 4.0 | 57.0 ± 7.5 | 15.0 | |
| 5.0 | 59.1 ± 3.3 | 15.6 | |
| 6.0 | 64.3 ± 6.6 | 16.9 | |
| Benzene | 3.0 | 36.6 ± 0.9 | 9.6 |
| Styrene | 3.0 | 32.2 ± 3.4 | 8.5 |
| p-Xylene | 3.0 | 36.0 ± 4.9 | 9.5 |
| Ethylbenzene | 3.0 | 47.3 ± 4.1 | 12.4 |
| Propylbenzene | 3.0 | 59.0 ± 2.0 | 15.5 |
| Aliphatic solvents | |||
| Pentane | 1.0 | 30.1 ± 0.8 | 7.9 |
| Hexane | 1.0 | 25.2 ± 0.7 | 6.6 |
| Heptane | 1.0 | 34.2 ± 1.2 | 9.0 |
| Octane | 1.0 | 26.8 ± 0.1 | 7.1 |
| Nonane | 1.0 | 23.7 ± 1.0 | 6.2 |
| Alcohols | |||
| 1-Propanol | 3.0 | 22.2 ± 1.2 | 5.8 |
| 1-Butanol | 3.0 | 25.1 ± 0.5 | 6.6 |
| 1-Pentanol | 3.0 | 38.1 ± 1.2 | 10.0 |
| 1-Hexanol | 3.0 | 60.3 ± 2.1 | 15.9 |
| 1-Heptanol | 3.0 | 66.1 ± 0.2 | 17.4 |
| 1-Octanol | 3.0 | 46.2 ± 1.2 | 12.2 |
a
P. putida S12(pKRZ-srp) cells were grown to late exponential phase (optical density of 1.0 at 600 nm) in LB broth. β-Galactosidase was determined in cell extracts by the method of Miller (16).