TABLE 1.
Abilities of antibiotics to activate malA-lacZ in B. thailandensis
| Antibiotic (μg/ml)a | Antibiotic class | Relative malA-lacZ activityb |
|---|---|---|
| None | 1 | |
| Trimethoprim (15)c | THF pathway inhibitord | 9.7 (0.4) |
| Kanamycin (115) | Ribosomal inhibitor | 0.5 (0.1) |
| Zeocin (1,200) | DNA intercalator | 1.5 (0) |
| Mitomycin C (10) | DNA cross-linker | 4.3 (0.1) |
| Sulfamethoxazole (3,000) | THF pathway inhibitor | 10 (0.7) |
| Malleilactone (15) | Unknown | 12.3 (1.5) |
a
The concentration of antibiotic used is indicated in parentheses, and in each case, the concentration resulted in a 70 to 80% reduction in the growth yield, as determined by the OD600 taken at the time of β-galactosidase measurement.
b
Growth-adjusted β-galactosidase activity relative to that of the untreated control. The β-galactosidase activity and OD600 were determined after 24 h. The values are the means of the results of two independent experiments, with the range indicated in parentheses.
c
Trimethoprim was previously shown to activate malA-lacZ (11).
d
THF pathway, tetrahydrofolate reductase pathway.