TABLE 4.
Extracellular pH values of the medium after 15 or 30 min of exposure of H. pylori strains in PBS at an initial pH of 2.2 in the presence of 5 or 10 mM urea
| Strain | pH valuea
|
|||
|---|---|---|---|---|
| 15 min and 5 mM urea | 30 min and 5 mM urea | 15 min and 10 mM urea | 30 min and 10 mM urea | |
| SS1 | 3.94 (0.85) | 5.26 (0.42) | 6.21 (0.13) | 6.40 (0.08) |
| SS1 Δ(β-CA-HP) | 2.75 (0.14) | 4.41 (1.00) | 2.97 (0.34) | 6.32 (0.25) |
| SS1 Δ(α-CA-HP) | 2.56 (0.10) | 3.12 (0.39) | 2.57 (0.01) | 4.94 (0.84) |
| SS1 Δ(α+β-CA-HP) | 2.61 (0.25) | 3.24 (0.91) | 2.53 (0.03) | 4.41 (1.17) |
| N6 | 5.04 (0.26) | 5.61 (0.43) | 6.37 (0.06) | 6.60 (0.12) |
| N6 Δ(β-CA-HP) | 4.24 (1.51) | 5.63 (0.31) | 6.28 (0.16) | 6.55 (0.12) |
| N6 Δ(α-CA-HP) | 2.92 (0.12) | 5.46 (0.23) | 4.69 (1.47) | 6.58 (0.11) |
| N6 Δ(α+β-CA-HP) | 2.93 (0.33) | 4.50 (0.50) | 3.92 (1.39) | 6.44 (0.10) |
| X47-2AL | 2.58 (0.10) | 2.86 (0.28) | 2.62 (0.17) | 5.75 (0.32) |
| X47-2AL Δ(β-CA-HP) | 2.43 (0.10) | 2.86 (0.44) | 2.52 (0.12) | 5.70 (0.26) |
| X47-2AL Δ(α-CA-HP) | 2.39 (0.04) | 2.58 (0.07) | 2.42 (0.05) | 2.98 (0.46) |
| X47-2AL Δ(α+β-CA-HP) | 2.41 (0.01) | 2.52 (0.17) | 2.47 (0.04) | 3.18 (0.76) |
| 26695 | 2.57 (0.07) | 3.78 (0.24) | 2.68 (0.24) | 6.01 (0.17) |
| 26695 Δ(β-CA-HP) | 2.42 (0.06) | 3.33 (0.49) | 2.48 (0.10) | 5.25 (1.45) |
| 26695 Δ(α-CA-HP) | 2.39 (0.10) | 2.68 (0.06) | 2.47 (0.06) | 2.89 (0.24) |
| 26695 Δ(α+β-CA-HP) | 2.42 (0.09) | 2.70 (0.21) | 2.51 (0.03) | 3.11 (0.50) |
a
Values significantly different from the wild-type value are indicated by bold type (P < 0.05, Student t test). The data are results from at least three independent experiments. The values in parentheses are standard deviations.