TABLE 2.
Toxicity of Cry2Aa1 and the mutant proteins against L. dispar larvaea
| Protein | LC50 (ng/cm2)
|
||
|---|---|---|---|
| No digestion | Digestion with:
|
||
| Gut juice | Chymotrypsin | ||
| Cry2Aa1 | 5.6 (2.1–8.7) | NDb | ND |
| L144A | 3.1 (0.9–5.8) | 5.2 (1.1–9.5) | 5.8 (4.2–7.1) |
| L144D | 6.4 (3.5–9.1) | 4.2 (0.5–7.7) | 6.9 (2.9–10.5) |
| L144G | 4.8 (1.3–8.1) | 8.0 (5.2–11.4) | 7.7 (2.1–12.8) |
| L144H | 8.8 (4.5–12.3) | 18.4 (9.7–25.3) | 19.6 (10.4–29.1) |
| L144V | 6.3 (4.7–7.4) | 2.8 (0.7–5.2) | 7.1 (5.0–9.7) |
a
The proteins were digested with midgut extract (1:50 [vol/vol]) or chymotrypsin (20% [wt/wt]) for 1 h before the treatment was administered to the insect larvae. Confidence intervals (95%) are given in parentheses.
b
ND, not detectable (no mortality was observed for protein concentrations in the range of 5 to 5,000 ng/cm2).