Bean halo-blight toxin

摘要: Pseudomonas phaseolicola causes a disease of beans commonly called halo blight. The is chlorotic zone which appears in the leaf round each infection site. It has been interpreted as effect toxin produced at, and diffusing away from, characteristically contains relatively large amount amino acid ornithine1. When Ps. was grown defined liquid culture medium at 18°C filter-sterilised medium, when applied to bean leaves, caused chlorosis symptom disease2. From such media I have isolated substance, 80–90% pure, which, introduced level 100 ng per g fresh weight, both accumulation ornithine. report here highly unusual structure this compound. Its extreme lability presence weak acids made its isolation difficult, but helped resolution structure.