title: Preparation of a beta-amanitin-concanavalin A conjugate of low toxicity.
abstract: Pure beta-amanitin was isolated by combined adsorption chromatography of a crude methanol extract from Amanita phalloides on Sephasorb HP Ultrafine and Sephadex LH-20. The beta-amanitin was coupled to concanavalin A by the carbodiimide method. The conjugate was purified by fractionation on a column of Sephadex G-75. The molar ratio beta-amanitin to concanavalin A in this conjugate was 4.14. The purified conjugate was tested by thin-layer chromatography and showed characteristic (for amatoxins) bright purple staining but different mobility. The ultraviolet spectrum of the conjugate was different from the spectra of the native beta-amanitin and the native concanavalin A. The toxicity of the conjugate was determined by in vivo toxicological studies and was four-fold lower than that of the native beta-amanitin. These results suggest that this conjugate may be used for immunization procedures and for the production of amatoxin-specific antibodies.
mesh_terms: D000546:Amanitins / Q000032:analysis / Q000633:toxicity; D000818:Animals; D002855:Chromatography, Thin Layer; D003208:Concanavalin A; D005779:Immunodiffusion; D013056:Spectrophotometry, Ultraviolet
chemical_list: D000546:Amanitins; D003208:Concanavalin A; C049197:beta-amanitin