x1 = PII
x2 = UTP
x3 = PIIUMP
x4 = PPi
x5 = GLN
x6 = PIIUMP2
x7 = PIIUMP3
x8 = UMP
x9 = GS
x10 = AMP
x11 = NH4
x12 = KG
x13 = NADPH
x14 = GLU
x15 = NADP
x16 = AZGLU
x17 = ATP
x18 = ADP
x19 = AZglu
x20 = AZGLN
x21 = AZgln
x22 = P_i