Thiol-specific peroxidase that catalyzes the reduction of hydrogen peroxide and organic hydroperoxides to water and alcohols, respectively (, ). Can reduce H(2)O(2) and short chain organic, fatty acid, and phospholipid hydroperoxides . Also has phospholipase activity, can therefore either reduce the oxidized sn-2 fatty acyl group of phospholipids (peroxidase activity) or hydrolyze the sn-2 ester bond of phospholipids (phospholipase activity) (, ). These activities are dependent on binding to phospholipids at acidic pH and to oxidized phospholipds at cytosolic pH . Plays a role in cell protection against oxidative stress by detoxifying peroxides and in phospholipid homeostasis . Exhibits acyl-CoA-dependent lysophospholipid acyltransferase which mediates the conversion of lysophosphatidylcholine (1-acyl-sn-glycero-3-phosphocholine or LPC) into phosphatidylcholine (1,2-diacyl-sn-glycero-3-phosphocholine or PC) . Shows a clear preference for LPC as the lysophospholipid and for palmitoyl CoA as the fatty acyl substrate .
Subcellular locations: Cytoplasm, Lysosome
Also found in lung secretory organelles (lamellar bodies).