x1 = E1
x2 = E2
x3 = KKK
x4 = P_KKK
x5 = KK
x6 = P_KK
x7 = PP_KK
x8 = K
x9 = P_K
x10 = PP_K
x11 = KPase
x12 = KKPase
x13 = E1_KKK
x14 = E2_P_KKK
x15 = P_KKK_KK
x16 = P_KKK_P_KK
x17 = PP_KK_K
x18 = PP_KK_P_K
x19 = KKPase_PP_KK
x20 = KKPase_P_KK
x21 = KPase_PP_K
x22 = KPase_P_K
x23 = K_PP_norm
x24 = KK_PP_norm
x25 = KKK_P_norm
x26 = rel_K_PP_max