Table 2.
β-glucuronidase activity of strains containing a PexoY-GUS transcriptional fusion
| Genotype | Activity (Miller units) |
Normalized to appropriate WT control |
|---|---|---|
| WT | 5.2 ± 0.2 | 1.0 |
| exoS(I87V) | 55.2 ± 1.0 | 10.7 |
| exoS(G268S) | 57.1 ± 9.6 | 11.0 |
| exoR(S156Y) | 64.2 ± 5.5 | 12.4 |
| exoR(G76C) | 67.2 ± 11.5 | 13.0 |
| chvI(K214T) | 2.3 ± 0.2 | 0.4 |
| chvI(K214T) exoS(I87V) | 5.9 ± 0.7 | 1.1 |
| chvI(K214T) exoS(G268S) | 4.4 ± 0.4 | 0.8 |
| chvI(K214T) exoR(S156Y) | 6.5 ± 0.4 | 1.3 |
| chvI(K214T) exoR(G76C) | 6.6 ± 0.6 | 1.3 |
| WT + pexoS | 3.9 ± 0.5 | 1.0 |
| exoS(I87V) + pexoS | 11.9 ± 1.8 | 3.1 |
| exoS(G268S) + pexoS | 10.2 ± 0.2 | 2.6 |
| WT + pexoR | 2.8 ± 0.4 | 1.0 |
| exoR(S156Y) + pexoR | 2.6 ± 0.7 | 0.9 |
| exoR(G76C) + pexoR | 3.4 ± 0.4 | 1.2 |
All normalizations are to WT except for strains with pexoS (normalized to WT + pexoS) and strains with pexoR (normalized to WT + pexoR). Means and standard deviations are shown for two independent cultures grown in LB and assayed in duplicate for each genotype. The experiment was performed three times with similar results. All strains contained integrated PexoY::uidA (pEC339). pexoS (pEC70) and pexoR (pDW85) are low-copy plasmids with exoS or exoR expressed from its native promoter.