FIG. 5.

¹H NMR spectroscopic time course analysis of the Irp9 reaction at 10°C using 5 μM Irp9 acting on an equilibrium mixture of chorismate and isochorismate formed from chorismate (2 mM) by the action of EntC, which was removed prior to the addition of Irp9 after 3 min (A), after 40 min (B), and at completion after 90 min (C). The signals for isochorismate in solution disappear faster than those for chorismate. Eventually, both are converted to salicylate. The abbreviations C, I, and S indicate protons from chorismate, isochorismate, and salicylate, respectively.