Rhizobitoxine is synthesized by the legume symbiont Bradyrhizobium elkanii
and the plant pathogen Burkholderia andropogonis. Rhizobitoxine competitive
ly inhibited 1-aminocyclopropane-1-carboxylate (ACC) synthase bLE-ACS2 from
the tomato, a key enzyme in the pathway of ethylene biosynthesis. Based on
this inhibition of ACC synthase, we have developed a new assay for rhizobi
toxine.