TABLE 3.
Serum resistance associated with O157 polysaccharide
| Strains | Percentage of viable E. colia
|
||
|---|---|---|---|
| Time 0 | Time 1 h | Time 1 h (heat-inactivated) | |
|
| |||
| % | % | % | |
| Wild-type O157:H7 4304 | 100 | 96.6 | 97 |
| ΔmsbB1, ΔmsbB2 | 100 | 30 | 88.3 |
| ΔmsbB1, ΔmsbB2, pagP::aacC1 | 100 | 90.6 | 98.3 |
| Wild-type K-12 MC1061 | 100 | 27.4 | 76 |
a
The numbers of E. coli were calculated as mean values of at least two independent experiments with the same nonimmune calf serum as described under “Experimental Procedures,” and percentages were determined in relation to the time 0 viable counts.