Figure 6. Impact of recombinant AIF on the arylating capacity of menadione.

To assess the arylating activity of menadione and evaluate the capacity of AIF to stimulate the formation of thioester bonds between menadione and GSH, menadione (250 μM) was directly added to an aqueous solution of GSH (100mM) in the absence or presence of recombinant purified AIF (40 μg/ml). Emission spectra were analyzed after excitation at 340 nm. The combination of menadione with GSH (purple line) produced fluorescence. The addition of recombinant AIF stimulated the arylating capacity of menadione that could be measured by the enhancement of the fluorescence (orange line). No fluorescence was detected for menadione, GSH alone or the combination of menadione with AIF alone.