Panel A, analysis of hemolytic activity of activated Cyt1Aa protein or its N- and C-terminal domains against red blood cells as described in experimental procedures. ■, Cyt1Aa toxin; ◇, N-terminal domain; X, C-terminal domain; and ◆. P-20 protein. Panel B, analysis of the effect of N- and C- terminal fragments at different molar ratios on Cyt1Aa hemolytic activity. The fragments were pre-mixed with a Cyt1Aa protein concentration that gave 80 % hemolytic activity (60 ng/ml). Panel C, analysis of the effect of N- and C- terminal fragments at different molar ratios on Cyt1Aa insecticidal activity against A. aegypti larvae. The fragments were pre-mixed with a Cyt1Aa protein concentration that that kill 80 % of the larvae (1.2 µg/ml). Each value in panel B and C represents the mean ±SD of four independent experiments. A t-test was used to analyze statistical differences of mean values of percentage of hemolysis or percentage of mortality induced by the toxin:fragment mixtures compared with the control (only toxin 1:0 ratio). Bars labeled with different letters indicated that differences were statistically significant. Black bars, mixtures of Cyt1Aa with N-terminal fragment; white bars, mixtures of Cyt1Aa with C-terminal fragment and dashed bars represent the mixture of p20 protein with Cyt1Aa.