Fig. 2.

Compartment specific ascorbate labeling within leaf mesophyll cells of Pseudomonas syringae-inoculated Arabidopsis thaliana Col-0 plants. Measurements were performed 0 (=control, C, represented by the dotted line), 12, 24, and 48 h postinoculation with the virulent strain Pseudomonas syringae pv. tomato DC3000 (black squares) and avirulent strain Pseudomonas syringae pv. tomato DC3000 AvrRpm1 (black circles). Data show means with standard errors and document the amount of gold particles bound to ascorbate per square micrometer in the respective cell compartment. n > 20 for peroxisomes and vacuoles and n > 60 for other cell structures. Different lowercase letters indicate significant differences between the data points. Significant differences were calculated with the Kruskal-Wallis test followed by post-hoc comparison according to Conover at P < 0.05.