Peroxiredoxin-6 is a member of the thiol-specific antioxidant protein family. This protein is a bifunctional enzyme with two distinct active sites. It is involved in redox regulation of the cell; it can reduce H(2)O(2) and short chain organic, fatty acid, and phospholipid hydroperoxides. It may play a role in the regulation of phospholipid turnover as well as in protection against oxidative injury. Kim et al. (1997) isolated a calcium-independent lysosomal PLA2 from a human myeloblast cell line. The predicted 224aa protein contained the PLA2 catalytic motif, but no other significant homology to known phospholipases. Expressed protein had significant PLA2 activity on several substrates.