Stimulation of Ethylene Production in Bean Leaf Discs by the Pseudomonad Phytotoxin Coronatine

摘要: Coronatine is a toxin produced by Pseudomonas syringae pv. glycinea which induces the same chlorotic response in bean leaves as does infection bacterial pathogen. Although structure of coronatine known, biological mode action not. One possible clue to its activity ethyl-substituted cyclopropane side chain molecule. This part (1-amino-2-ethycyclopropane-1-carboxylic acid or AEC) an analog ethylene precursor 1-aminocyclopropane-1-carboxylic (ACC). When was applied leaf discs solution, intact through prick application, substantial stimulation production measured. concomitant with increase ACC content tissue, and occurred under conditions did toxin. The inhibited aminoethoxyvinylglycine, inhibitor synthesis. These results, along those experiments using l-[U- 14 C]methionine, indicated that involved de novo via methionine pathway. whole, unhydrolyzed molecule probably necessary elicit both chlorosis responses since neither hydrolysis product (coronafacic coronamic AEC]) effective alone. A naturally occurring coronatine, coronafacoylvaline, also stimulated caused chlorosis. However, unrelated pseudomonad phytotoxin phaseolotoxin, causes chlorosis, not stimulate production. Ethylene thus may have specific role toxic syndrome.