. "cGMP is required to activate this enzyme." . "The enzyme occurs as a dimer in higher eukaryotes." . "The C-terminal region of each polypeptide chain contains the catalytic domain that includes the ATP and protein substrate binding sites." . "This domain catalyzes the phosphorylation by ATP to specific serine or threonine residues in protein substrates." . "The enzyme also has two allosteric cGMP-binding sites (sites A and B)." . "Binding of cGMP causes a conformational change that is associated with activation of the kinase." . . . "cGMP-dependent protein kinase" . "PKG" . "PKG II" . "3':5'-cyclic GMP-dependent protein kinase" . "cGMP-dependent protein kinase I-beta" . "Guanosine 3':5'-cyclic monophosphate-dependent protein kinase" . "PKG 1-alpha" . "PKG 1-beta" . . "ATP + a protein = ADP + a phosphoprotein." . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .