Table 1.
Toxin | Amino Acids at Position 291 and 297, Respectively | Log Specific Activity, CD50/mg | CD50 95% Confidence Interval | LD50, ng | LD50 95% Confidence Interval, ng |
---|---|---|---|---|---|
Stx2c/c | F, K | 7.0 | 6.5–7.5 | 14 | 5.1–38 |
Stx2d/d | S, E | 7.0 | 5.5–7.0 | 1.8 | 0.94–3.0 |
Stx2c/d | F, E | 6.3 * | 7.0–7.9 | 24 | 12–49 |
Stx2d/c | S, K | 7.4 | 6.8–7.1 | 2.5 | 1.5–3.9 |
* The specific activity of Stx2c/d was significantly reduced compared to the three other toxins, p ≤ 0.025 as determined by analysis of variance followed by unpaired t tests.