This is the C-terminal domain of 1-Cys peroxiredoxin (1-cysPrx),a member of the peroxiredoxin superfamily which protect cellsagainst membrane oxidation through glutathione (GSH)-dependentreduction of phospholipid hydroperoxides to correspondingalcohols [1]. The C-terminal domain is crucial for providing theextra cysteine necessary for dimerisation of the whole molecule.Loss of the enzyme's peroxidase activity is associated withoxidation of the catalytic cysteine, upstream of this domain;and glutathionylation, presumably through its disruption ofprotein structure, facilitates access for GSH, resulting inspontaneous reduction of the mixed disulfide to the sulfhydryland consequent activation of the enzyme [2]. C-terminal domain of 1-Cys peroxiredoxin 1-cysPrx_C