Салицилгидроксамат Усиливает НАДН-оксидазную Активность Пероксидазы В Суспензиях Митохондрий И Хлоропластов Гороха

Salicylhydroxamic acid (SHAM), an inhibitor of the alternative oxidase in plant mitochondria, accelerated the NADH-oxidase activity in suspensions of mitochondria and chloroplasts, obtained by their isolation from the roots or leaves of pea, respectively. The reaction was suppressed by washing mitochondria and chloroplasts. It also proceeded in supernatants where the organelles were removed by centrifugation. The reaction was sensitive to CN– and propyl gallate, an antioxidant. In addition to SHAM, NADH oxidation was stimulated by 2,4-dichlorophenol or phenol, but not by salicylic acid. The acceleration of NADH oxidation by the phenolic compounds occurred in the presence of commercial horseradish peroxidase. It is due to the involvement of these compounds in the NADH-dependent peroxidase reaction. 2,4-Dichlorophenol and SHAM enhanced significantly destruction of nuclei in guard cells of the epidermis from pea leaves induced by generation of reactive oxygen species under oxidation of exogenous NADH by means of the apoplastic peroxidase.