INHIBITION OF APPLE FRUIT 1-AMINOCYCLOPROPANE-1-CARBOXYLIC ACID OXIDASE ACTIVITY AND RESPIRATION BY ACETYLSALICYLIC-ACID

Acetylsalicylic acid (aspirin) inhibited ethylene production of apple (Malus domestica Borkh. cv. Granny Smith) fruit discs in a concentrati on and time-dependent fashion. Activity of 1-aminocyclopropane-1-carbo xylic acid (ACC) oxidase was inhibited both in vivo and in vitro by ac etylsalicylic acid, both V-max and K-m decreased as acetylsalicylic ac id concentration increased. The apparent Ki was 0.12 mmol . L(-1). We conclude acetylsalicylic acid inhibits ethylene production by inhibiti ng ACC oxidase activity. For unknown reasons, acetylsalicylic acid als o inhibited fruit respiration.