TABLE 4.
Dissociation constants (Kd) and concentration of binding sites (Rt) for binding of Cry1A proteins to BBMV from H. zeaa
| B. thuringiensis toxin | Sample (generation of selection)b | Kd ± SD (nM) | Rt ± SD (pmol/mg)c |
|---|---|---|---|
| Cry1Ac | SC | 1.1 ± 0.1 | 17.0 ± 0.9 |
| AR (4) | 0.50 ± 0.3 | 22.3 ± 4.9 | |
| AR (7) | 0.4 ± 0.1 | 28 ± 15 | |
| AR (11) | 2.9 ± 0.1 | 49 ± 3 | |
| Cry1Aa | SC | 3.2 ± 0.4 | 2.7 ± 0.7 |
| AR (7) | 3.8 ± 0.1 | 4.1 ± 0.7 | |
| AR (11) | 3.2 ± 0.3 | 5.0 ± 1.2 |
a
Values are the means of two replicates for resistant insects and four replicates for the SC strain (using two independently labeled Cry1Ac and Cry1Aa batches).
b
SC, susceptible colony; AR, Cry1Ac-resistant colony.
c
Expressed as pmol per milligram of total vesicle protein.