A CDNA CLONE OF EEL LIVER GLUTAMATE-DEHYDROGENASE AND ITS DEDUCED AMINO-ACID-SEQUENCE

A cDNA clone of eel liver glutamate dehydrogenase (GDH) from an eel liver cDNA library was obtained by using the cDNA of human liver GDH as a probe for screening. The amino acid sequence deduced from the nucleotide sequence of the obtained cDNA consisted of 463 amino acids and contained the C-terminal, but did not contain the N-terminal. The sequence corresponds to that from the 43rd to 505th position from the N-terminal of human liver GDH and the homology between eel and human was 89%. The sequence around essential Lys for enzyme activity, which corresponds to the sequence from Va1103 to Pro137 of human liver GDH, is identical between liver GDHs from eel, tuna, human, bovine, rat, and chicken. Eel GDH has six Cys residues and their positions are conserved in all the liver GDHs described above. Considering the 39 amino acid sequence from the N-terminal, which was determined from the purified enzyme previously, the predicted complete primary structure of eel liver GDH was described.