FIG 4.
Toxicity of limonene at different degrees of oxidation. (A) Specific growth rate plotted against the limonene concentration for nonoxidized, anaerobically stored limonene (left) and fully oxidized limonene (exposed to air and light for 3 weeks) (right). (Top) Wild-type BW25113; (bottom) a ΔahpC strain expressing AhpCL177Q. (B) Limonene toxicity, defined as the inverse of the shaded areas in panel A, plotted against the limonene hydroperoxide content (LC-TOF-MS peak area, in arbitrary units). Each point represents 1 of 13 limonene bottles subjected to various degrees of oxidation. Blue points, wild-type BW25113; green points, a ΔahpC strain expressing AhpCL177Q.