Survival of L. oleracea larvae following injection of purified recombinant proteins. Survival was recorded for fifth stadium L. oleracea larvae following injections of recombinant GNA or ButaIT/GNA. Control insects were injected with phosphate buffered saline (PBS; n = 40). GNA was injected at a dose of 20 μg which equates to approx. 500 μg GNA/g insect (n = 20); ButaIT/GNA was injected at two different concentrations; 4 μg which equates to approx. 100 μg fusion protein or 30 μg toxin/g insect (n = 25), and 20 μg which equates to approx. 450 μg of fusion protein or 135 μg toxin/g insect (n = 10).