Removing influences of GSH on methylation. The left and right panels both reproduce the experimental data,  red and  green, and blue model curve for MMAs + DMAs with varying amounts of GSH from the right panel of Figure 4. The black curve in the left panel shows what the model fit would be if we removed from the model the excitatory influence of GSH on AS3MT. The black curve in the right panel shows what our model fit would be if we removed the binding of arsenicals to GSH from the model. Clearly, neither black curve fits the data. Both influences of GSH (blue curve) are necessary to explain the experimental data.