x1 = H2_HMPt x2 = ATP x3 = H2_HMPterinPP x4 = AMP x5 = p_ABA x6 = PPi x7 = H2_Pteroate x8 = L_Glutamate x9 = Phosphate x10 = ADP x11 = DHF x12 = L_serine x13 = Glycine x14 = NADP x15 = NADPH x16 = THF x17 = CH2_THF