Fig. 3 in Roles of cell wall peroxidases in plant development

Fig. 3. CIII Prx-mediated redox electron transfer and positioning of pharmacological inhibitors and chromogenic/fluorogenic probes and substrates. The different steps of the enzyme-mediated redox electron transfer from O2 allowing aromatic ring oxidation (peroxidative cycle on the left) and OH. production (hydroxylic cycle on the right) by CIII Prxs are represented in black. NADPH oxidase (RBOH), superoxide dismutase (SOD) and CIII Prxs are positioned and underlined in blue and orange, respectively. Pharmacological inhibitors (in red) are positioned from the top to the bottom as follows. DPI: diphenyleneiodonium, NADPH oxidase (RBOH) inhibitor; SHAM: salicylhydroxamic acid, CIII Prx inhibitor; KCN: potassium cyanide, CIII Prx inhibitor; MnDFA: manganese desferal, O.― scavenger; DDC: diethyldithiocarbamic 2 acid, superoxide dismutase (SOD) inhibitor; KI: potassium iodide, H2O2 scavenger; Benzoate, OH. scavenger; Note that KCN and SHAM inhibit all CIII Prx isoforms. Chromogenic/fluorogenic substrates and probes (in green) are positioned from the top to the bottom as follows. NBT: nitroblue tetrazolium, chromogenic probe for O . ― ; 4 CN: 4-chloronaphtol; DAB: diaminobenzidine; guaiacol and O-dianisidine are 2 chromogenic probes for H2O2 and/or substrates for CIII Prxs depending on the addition of exogenous CIII Prx and/or H O, respectively. HPF: 30-(p-hydroxyphenyl) 2 2 fluorescein is a fluorogenic probe for H2O2 and/or substrate for CIII Prxs depending on the addition of exogenous CIII Prx and/or H2O2, respectively. Note that chromogenic/fluorogenic CIII Prx substrates are substrates for all CIII Prx isoforms.