TABLE 5.
Role of intracellular ILV synthesis and BCAA permeases in CodY activitya
| Strain | Relevant genotype | Fusion type | β-Galactosidase activity (Miller units) |
||
|---|---|---|---|---|---|
| No additions | ILV | ILV + 13 aa | |||
| BB2676 | Wild type | dppA-lacZ | 90.3 | 37.3 | 5.79 |
| BB3152 | liv | NG | 36.2 | 4.56 | |
| BB2505 | Wild type | bcaP-lacZ | 55.9 | 7.47 | 0.14 |
| BB3150 | liv | NG | 8.09 | 0.13 | |
| BB3113 | bcaP braB brnQ | 53.5 | 17.7 | 13.6 | |
| BB3283 | bcaPp10/14 | ND | 3.63 | 0.13 | |
| BB2770 | Wild type | ybgE-lacZ | 19.2 | 3.49 | 1.12 |
| BB2870 | liv | NG | 3.25 | 0.87 | |
| BB3114 | bcaP braB brnQ | 22.8 | 6.25 | 9.76 | |
| BB3284 | bcaPp10/14 | ND | 2.24 | 1.00 | |
a
Cells were grown in TSS glucose-ammonium medium with or without mixtures of ILV (200 μg/ml) and 13 amino acids. The β-galactosidase specific activity was assayed and is expressed in Miller units. All values are averages from at least two experiments, and the mean errors did not exceed 30%. The data for strains BB2505 and BB2770 were taken from previous publications (22, 23). NG, no growth; ND, not determined.