FIGURE 9.

Immunospin trapping of protein thiyl radical in the peroxynitrite reaction with Fe-SODB. A, control or thiol-blocked NEM-treated Fe-SODB (50 μm) was exposed to peroxynitrite (0–20 μm) in sodium phosphate buffer (100 mm, pH 7.4) in the presence of the spin trap DMPO (100 mm). Immunoreactive proteins were detected with anti-DMPO nitrone antibody (green) and specific anti-Fe-SODB antibody (red). Merged bands are shown in yellow. B, two-dimensional gel electrophoresis of T. cruzi Fe-SODB (8 μm) treated with peroxynitrite (300 μm) in sodium phosphate buffer (0.2 m) at pH 7.4 and 25 °C in the presence and absence of DMPO (100 mm). Two-dimensional gel electrophoresis was performed as described under “Experimental Procedures.”