Figure 3.

The Cys137 residue is crucial for the persulfidation of CSE. (a–c) Recombinant CSE variants CSE (C109S), CSE (C172S) and CSE (C137S) were incubated with diamide (Dia) and Na₂S for persulfidation according to the legend of Figure 1. (d) Recombinant CSE (C137S) protein (1 mg/mL) was incubated with 50 µM H₂O₂ and 250 µM Na₂S for persulfidation. DTT was used to reduce the persulfidated CSE. After the complete removal of DTT using a desalting column, the proteins were reoxidized by bubbling air through the solution. The data points and errors are the means ± SDs (n = 4).