isochorismate + 2-oxoglutarate + H(+) = 5-enolpyruvoyl-6-hydroxy-2-succinyl-cyclohex-3-ene-1-carboxylate + CO2
isochorismate + 2-oxoglutarate + h(+) = 5-enolpyruvoyl-6-hydroxy-2-succinyl-cyclohex-3-ene-1-carboxylate + co2