Table 4.
Susceptibility of B. ovis PA and selected mutants to polymyxin B and Na deoxycholate.
| % Survival after exposure toa: |
||
|---|---|---|
| Brucella ovis strainsb | Polymyxin B (1 mg/ml) | Na deoxycholate (0.1 mg/ml) |
| B. ovis PA | 69.03 6.12 | 86.25 5.74 |
| Single mutants | ||
| Δomp31 | 27.47 3.04* | 83.74 3.09 |
| Δomp25 | 65.84 7.17 | 92.94 4.06 |
| Δomp25c-k | 65.99 4.72 | 95.89 7.15 |
| Δcgs | 77.96 11.80 | 79.82 9.07 |
| ΔbacA | 84.10 5.49* | 87.38 8.28 |
| Δomp10 | 62.04 3.46 | 91.20 4.22 |
| Δomp19 | 67.27 7.05 | 83.19 7.75 |
| ΔugpB | 77.59 11.67 | 90.66 9.42 |
| Double mutants | ||
| Δomp31Δomp19 | 25.68 2.94* | 90.49 7.79 |
| Δomp31ΔugpB | 20.66 0.57* | 92.65 3.64 |
| Δomp31Δcgs | 31.20 14.30* | 32.14 1.27* |
| Δomp25Δcgs | 61.71 7.30 | 92.35 5.18 |
| Δomp25Δomp25c | 45.23 5.10* | 91.36 9.59 |
| Δomp10Δomp31 | 33.31 4.58* | 84.66 6.36 |
| Δomp10ΔugpB | 64.22 5.36 | 77.93 9.26 |
| ΔbacAΔomp31 | 88.06 18.61* | 86.90 5.51 |
| Triple mutants | ||
| Δomp10ΔugpBΔomp31 | 30.50 9.94* | 88.52 6.22 |
| Δomp10Δomp31Δomp25c | 1.65 0.36* | 76.74 9.37 |
| Δomp31Δomp10Δomp25c | 7.19 4.38* | 80.40 7.49 |
| Δomp31ΔcgsΔomp10 | 37.84 9.43* | 33.63 1.78* |
| Δomp31ΔcgsΔomp19 | 33.30 3.68* | 34.39 2.94* |
aResults are expressed as the mean ± SD of three assays. Statistically significant differences (P < 0.05), compared to the parental strain, are marked with an asterisk. bSee legend to Figure 1 for strain characteristics.