Cytotoxic proteins of Amanita virosa Secr. mushroom: Purification, characteristics and action towards mammalian cells

Abstract

A new hemolytic lectin was purified from the fruit bodies of Amanita virosa Secr. mushroom by the affinity chromatography on the cross-linked ovomucin. This lectin destroyed erythrocytes of human and animals of various species, and its hemolytic activity decreased in the row: rabbit > rat > human > dog. The erythrocytes of sheep, cow and carp were resistant to such hemolytic action of the lectin (1 mg/mL). The lectin-mediated hemolysis was blocked by the polyethylene glycol with molecular mass over 1350. A. virosa lectin, unlike Amanita phalloides lectin, did not interact with tested monosaccharides. However, the 4-nitrophenyl derivates of the monosaccharides inhibited the action of A. virosa lectin which did not prefer targeting O-type glycoproteins over the N-type glycoproteins. Murine leukemia cells of L1210 line and human leukemia T-cells of CEM T4 and Jurkat lines were shown to be sensitive to toxic effect of the lectin and another protein toxovirin isolated from A. virosa fruit bodies It was found that toxovirin possessed an enzymatic activity of l-amino acid oxidase. Since both toxic proteins – the lectin and toxovirin – are sensitive to an elevated temperature, it is suggested that they play a significant role in human poisoning only when the unbaked mushroom is eaten.