The α-subunit primary structure of cyclic GMP phosphodiesterase has been determined by parallel analysis of the protein amino acid sequence and the corresponding cDNA nucleotide sequence. The enzyme α-subunit contains 858 amino acid residues, its N-terminal amino group being acetylated. The partial primary structure of the enzyme, β-subunit has also been elucidated. A significant homology has been found between the α- and β-subunits of cGMP phosphodiesterase.
