Volume 10, Number 8—August 2004
Dispatch
Human Escherichia coli O157:H7 Genetic Marker in Isolates of Bovine Origin
Table 2
Shiga toxin production by Escherichia coli O157:H7 by Q allele
| Assay |
Response |
|||
|---|---|---|---|---|
| Q allele | Median | Minimum | Maximum | |
| OD600nm noninduced |
Q933 |
0.442 |
0.153 |
2.814 |
| Q21 |
0.170 |
0.120 |
0.413 |
|
| OD600nm induced |
Q933 |
1.228 |
0.172 |
2.896 |
| Q21 |
0.165 |
0.084 |
1.210 |
|
| Fold increase in OD600nm after inductiona | Q933 |
2.2 |
0.3 |
7.7 |
| Q21 | 0.9 | 0.4 | 5.1 | |
a(ODinduced)/(ODnoninduced). The maximum and minimum optical density readings at 600 nm listed in each row are not necessarily from the same isolate; therefore, the maximum- and minimum-fold increase cannot be calculated directly from the table.


