S-nitrosylation of FBPase mutants in the Cys of the redox regulatory domain. A, S-nitrosylation assays with single mutants C153S, C173S, and C178S. B, S-nitrosylation assays with double (C153S C173S, C153S C178S, and C173S C178S) and triple (C153S C173S C178S) mutants. Experimental conditions were the same as the shown in the legend of Fig. 1. C, amino acid sequence of the redox regulatory domain indicating the mutated cysteines. S-nitrosylation assays are described in the Section 2. Membranes were incubated with antibodies anti-biotin (SNO-FBPase) or anti-cFBP1 (FBPase). 100 ng of recombinant FBPase were loaded per lane.