Glutathione transferase in helminths.

The helminth glutathione (GSH) transferases are present as isoenzymes but fail to show a clear biochemical homology to any of the three mammalian GSH transferase families. GSH transferase is one of the major detoxification systems found in helminths, particularly high levels being found in cestodes and digeneans. Helminth GSH transferases bind a range of anthelmintics but there is limited evidence that the enzymes can conjugate anthelmintics with glutathione. Other natural substrates of helminth GSH transferase may be secondary products of lipid peroxidation including lipid hydroperoxides and reactive carbonyls. Lipid peroxidation can arise via free radicals produced by host immuno-effector cells and helminth GSH transferase may help form a defence system against immune-mediated damage. GSH transferase has also been identified as a protective antigen in schistosomiasis.