Table I.
Construction of Recombinant Wild-Type and Chimeric Toxins
| Clone | Toxin or chimera | A1 subunit | Junction | A2 subunit B subunit | ||||
|---|---|---|---|---|---|---|---|---|
| pMGJ148 | CT (native) | CTA1 | CGNAP R*SSMSNTC | CTA2-CTB | ||||
| 187 199 | ||||||||
| pMGJ179 | CTA/LTIIbB | CTA1 | CGNAP R*SSMDTTC | LTIIbA2-LTIIbB | ||||
| 187 197 | ||||||||
| pMGJ183 | LTIIb(S193M) | LTIIbA1 | CLPNN*KASMDTTC | LTIIb A2-LTIIbB | ||||
| 185 197 | ||||||||
| pMGJ184 | LTIIbA/CTB | LTIIbA1 | CLPNN*KASMSNTC | CT A2-CTB | ||||
| 185 199 | ||||||||
| pMGJ187 | LTIIbA/CTB | LTIIbA1 | KKYIKRQIFF | LTIIbA2::CTA2-CTB | ||||
| 213 224 |
Amino acid sequences of the junctions formed between A1 and A2 peptides are shown in letter code. Numbers beneath cysteines indicate the position in the native protein. In the native protein these cysteines are linked by disulfhydryl bond.
*
above the letter codes identifies the serine-protease cleavage site linking the A1 and A2 peptides. The cleavage site for pMGJ187 is the same as for native LTIIb and the fusion joint (underlined) is within the A2 domain instead of between the A1 and A2 domains.