Contributes to oxidative stress resistance by reducing cysteine-sulfinic acid formed under exposure to oxidants in the peroxiredoxin TSA1. May catalyze the reduction in a multi-step process by acting both as a specific phosphotransferase and as thioltransferase. [protein]-dithiol + ATP + S-hydroxy-S-oxy-L-cysteinyl-[peroxiredoxin] = [protein]-disulfide + ADP + phosphate + S-hydroxy-L-cysteinyl-[peroxiredoxin] By hydrogen peroxide. Forms a transient disulfide bond with TSA1 during the reduction of cysteine sulfinic acid (-SO2H). Present with 538 molecules/cell in log phase SD medium. Belongs to the sulfiredoxin family.