Molecular cloning of cDNA coding for rat plasma glutathione peroxidase.

The plasma glutathione peroxidase (PGSH-PO), which is different from erythrocyte glutathione peroxidase (EGSH-PO) in immunochemical property and substrate specificity, was purified from male Wistar rat serum. The amino acid sequence of 5 independent peptides were determined and a cDNA clone for this enzyme was isolated from placental cDNA library. The nucleotide sequence of the cDNA revealed that, similar to EGSH-PO cDNA, the seleno-cysteine was genetically encoded by "TGA" codon. On comparing the nucleotide sequences of EGSH-PO and PGSH-PO, no significant homology was found in the vicinities of "TGA" codons of both enzymes.