A NARURALLY-OCCURRING STRUCTURAL ANALOGUE OF THE PHYTOTOXIN CORONATINE

Article abstract of DOI:10.1016/S0031-9422(00)85028-1

Chlorosis-inducing compounds in liquid cultures of the phytopathogenic bacterium Pseudomonas syringae pv. atropurpurea have been investigated.In addition to coronatine as previously reported, a new compound was discovered.This give a mass-spectral fragmentation pattern which indicated that it was, like coronatine, an amide of coronafacic acid.Acid-hydrolysis of the new toxin liberated the amino acid valine.This observation, together with mass spectral and MNR data, established the structure of the new toxin as N-coronafacoylvaline.Some implications to biosynthesis are discussed.Along with the two chlorosis-inducing compounds, the biologically inactive coronafacic acid was also isolated from the growth medium.Key Word Index - Pseudomonas syringae pv. atropurpurea; toxin; leaf chlorosis; coronatine; N-coronafacoylvaline; coronafacic acid.