FUNCTION: Involved in redox regulation of the cell. Can reduce H(2)O(2) and short chain organic, fatty acid, and phospholipid hydroperoxides. May play a role in the regulation of phospholipid turnover as well as in protection against oxidative injury. * CATALYTIC ACTIVITY: Donor + H2O2 = oxidized donor + 2 H2O. * SUBUNIT: Homodimer. * SUBCELLULAR LOCATION: Cytoplasmic, lysosomal and also found in lung secretory organelles (By similarity). * MISCELLANEOUS: The active site is the redox-active Cys-46 oxidized to Cys-SOH. Cys-SOH may rapidly react with a Cys-SH of the other subunit to form an intermolecular disulfide with a concomitant homodimer formation. The enzyme may be subsequently regenerated by reduction of the disulfide by thioredoxin. * MISCELLANEOUS: Irreversibly inactived by overoxidation of Cys-46 (to Cys-SO3H) upon oxidative stress. * SIMILARITY: BELONGS TO THE AHPC/TSA FAMILY. REHYDRIN SUBFAMILY. |
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16-JAN-03
Last Update 13-Mar-03