Fig 3. The trypanosome refractory phenotype exhibited by Gmm^Apo/Kco_Z flies is not directly caused by reactive oxygen intermediates.

(A) Percentage of Gmm^Apo, Gmm^Apo/Sgm and Gmm^Apo/Kco_Z flies harboring midgut infections with bloodstream form (BSF) YTAT 1.1 trypanosomes. Statistical analysis was performed using a GLM followed by multiple comparisons and Tukey contrasts, and different letters represents statistical significance between treatments and controls. (B) Mid-log phase cultures of Kco_Z and Sodalis synthesize similar quantities of H₂O₂ (p = 0.6; paired t-test). Measurements were taken from 7 distinct clonal populations of each bacterium. (C) Percentage of Gmm^Apo and Gmm^Apo/Kco_Z flies infected with BSF YTAT 1.1 trypanosomes after being fed blood meals containing antioxidant vitamin C over the course of the 14 day experiment. Despite exposure of both tsetse groups to the ROI-suppressing vitamin, Gmm^Apo/Kco_Z flies were still significantly more refractory to trypanosome infection than were Gmm^Apo individuals (p = 0.002; GLM Wald test). In (A), (B) and (C) different letters represents statistical significance between treatments and treatments and controls.