Figure 5. Exposure of CATP knockdown strain to hydrogen peroxide.

(A) Quantification of the sensitivity to H₂O₂ in P. brasiliensis yeast cells. Yeast cells were exposed to increasing concentrations of this compound and the inhibition zone was determined as the area lacking yeast cell growth. (Top) Data presented correspond to the average for three replicate tests, with error bars representing standard deviations. (Bottom) Images of P. brasiliensis growth around H₂O₂ saturated disks. Saturated filter disks without H₂O₂ as control, and 0.5 to 8 M H₂O₂. (B) Determination of the ability of P. brasiliensis yeast cells to degrade H₂O₂. Extracellular, cell wall and cytoplasmic fractions from PbWT, PbEV and PbCATP-aRNA strains were collected. Relative H₂O₂ destruction was measured as the decrease in the absorbance at 240 nm. Results are the mean of three individual experiments.