TABLE 2.
Relative promoter activities of nine motility genes determined in two regulatory mutant strains
| Plasmid (lacZ fusion) | Relative promoter activitya
|
Hierarchical classc | |
|---|---|---|---|
| In RU11/555 (Δrem) | In RU11/814 (ΔvisNR) | ||
| pRU2266 (visN)b | 0.96 | 0.93 | IA |
| pRU2361 (rem) | 1.24 | 0.02 | IB |
| pRU2265 (fliF) | 0.03 | 0.02 | II |
| pRU2269 (motA)b | 0.02 | 0.01 | II |
| pRU2271 (orf20)b | 0.02 | 0.01 | II |
| pRU2273 (flgB)b | 0 | 0 | II |
| pRU2278 (orf38)b | 0 | 0.03 | II |
| pRU2250 (icpA = tlpA)b | 0.03 | 0.01 | III |
| pRU2274 (flaA) | 0.17 | 0.05 | III |
Relative activities are expressed as the ratio of β-galactosidase activities (36) in a given mutant background to the wild-type background (set at 1.0). Transcription from nine promoters (leftmost column) was determined during early exponential growth via plasmid-borne lacZ fusions. Cells diluted in RB were layered on Bromfield agar plates and grown to an OD600 of 0.15 to 0.25 (see Materials and Methods). Results from three independent experiments were averaged, with standard deviations of less than 7%.
The operons indicated by their first genes (boldface type) have the following gene contents: visN visR; motA fliMNG; orf20 flgF fliI orf23; flgB flgC fliE flgGAI motE flgH fliLP; orf38 motBC fliK; icpA (tlpA) orf2 cheY1AWRBY2D orf10 (15, 55).
Classification is according to Sourjik et al. (52) and this work.