To identify proteins that interact with the yeast Tsa1 peroxiredoxin, we utilized an N-terminal Myc-tagged version of Tsa1 with a mutation in its resolving cysteineresidue (Tsa1-C171S) to trap and detect redox-dependent interactions. Yeast cells were left untreated, or treated with AZC or hydrogen peroxide prior to immunoprecipitation and mass spectrometry used to identify co-immunoprecipitating proteins.