TABLE 2.
Effects of dam and damX mutations on the expression of cea::lac and stdA::lac fusions
| Genotypea | β-Galactosidase activityb |
|
|---|---|---|
| cea::lacZ | sdtA::lacZ | |
| Wild type | 54.75 ± 2 | <1 |
| ΔdamX1 | 57.49 ± 2 | 15 ± 1 |
| ΔdamX2 | 55.36 ± 3 | <1 |
| Δdam-230 | 727.38 ± 63 | 1273 ± 88 |
a
The strains were SV4933 (ATCC 14028/pGE108), SV5119 (ΔdamX1/pGE108), SV5488 (ΔdamX2/pGE108), SV4930 (Δdam-230 /pGE108), SV5206 (stdA::lacZ), SV5287 (stdA::lacZ ΔdamX1), SV5486 (stdA::lacZ ΔdamX2), and SV5208 (stdA::lacZ Δdam-230). Strains SV4930 and SV4933 were described in reference 18. Strains SV5206 and SV5208 were described in reference 7.
b
Strains were grown in LB at 37°C with shaking. Aliquots for β-galactosidase analysis were extracted at an OD660 of 0.8. β-Galactosidase activities were assayed using the CHCl3-sodium dodecyl sulfate permeabilization procedure (14). Data are averages and standard deviations from 3 experiments.