TABLE 4.
Expression of psrA-lacZ, aefR-lacZ, and rpoS-lacZ fusions in E. coli strain MC4100 in the presence of psrA
| Bacterial constructa | Relevant characteristic | β-Galactosidase activity (mean ± SD)b |
|---|---|---|
| MC4100(pMMB66EHΩ, pMP220) | Vectors | 29 ± 6 |
| MC4100(pAKC1254, pMP220) | psrA + vector | 30 ± 3 |
| MC4100(pMMB66EHΩ, pAKC1257) | Vector + psrA-lacZ | 430 ± 17 |
| MC4100(pAKC1254, pAKC1257) | psrA + psrA-lacZ | 67 ± 8 |
| MC4100(pMMB66EHΩ, pAKC1258) | Vector + aefR-lacZ | 828 ± 33 |
| MC4100(pAKC1254, pAKC1258) | psrA + aefR-lacZ | 360 ± 12 |
| MC4100(pMMB66EHΩ, pAKC1259) | Vector + rpoS-lacZ | 101 ± 12 |
| MC4100(pAKC1254, pAKC1259) | psrA + rpoS-lacZ | 258 ± 21 |
a
Assays were performed with cultures grown in LB medium plus spectinomycin and tetracycline to a Klett value of ca. 500.
b
Expressed as Miller units.