FIGURE 5.

Identification of protein persulfides using 1,5-IAEDANS. A, persulfuration of DsrE2. The protein was reduced with DTT before incubation with sulfide, dialyzed, and treated with 1,5-IAEDANS and DTT as described under “Experimental Procedures.” Aliquots containing 200 pmol of protein were separated via SDS-PAGE (15%). B, persulfuration of DsrC after incubation with persulfidic Rhd_2599. 200 pmol of DsrC were added to 200 pmol of Rhd_2599, which had before been incubated with thiosulfate. After treatment with fluorescent 1,5-IAEDANS, the protein solution was analyzed via SDS-PAGE (15%). The upper images show the gels under UV light, and the lower images show the gels after staining with Coomassie. The molecular mass (MW) of the marker proteins is given in kDa.