Fig. 1.

Three pathways of S = adenosyl-L-methionine (SAMe) metabolism and the 1- carbon cycle. The transmethylation pathway (light blue), trans-sulfuration pathway (brown), and transaminopropylation pathway (purple); 1- carbon cycle: the folate cycle (green) and methionine cycle (dark blue). THF = tetrahydrafolate; 5-MTHF = 5-methyltetrahydrafolate; 5, 10 - methylenetetrahydrofolate; Hcy = homocysteine; Cys = cysteine; GSH = glutathione; Gly - Glycine; Met = Methione; SAH = Sadenosylhomocysteine; dSAM = decarboxylated S - adenosyl - L - methionine