Poisoning Amanita

PM] wieland, T., Peptides of Poisonous Amanita Mushrooms, Springer New York, (1986). 

Figure 28.16. RNA Polymerase Poison. Amanita phalloides, a poisonous mushroom that produces a-amanitin. [After G. Lincoff and D. H. Mitchel, Toxic and Hallucinogenic Mushroom Poisoning (Van Nostrand Reinhold, 1977), p. 30.]...

Eukaryotic RNA polymerases - Eukaryotes contain three distinct RNA polymerases, one each for the synthesis of the three larger rRNAs, mRNA, and small RNAs (tRNA plus the 5S species of rRNA). These are called RNA polymerases I (see here), II (here), and III (here), respectively. The enzymes differ in their sensitivity to inhibition by oi-amanitin (Figure 26.4b), a toxin from the poisonous Amanita mushroom. RNA polymerase II is inhibited at low concentrations, RNA polymerase III is inhibited at high concentrations, and RNA polymerase I is quite resistant. 

O. 5 mg kg causes fiill protection of mice from death by phalloidin phallotoxins) after injection about 1 h before or, at the latest, simultaneously with 5 mg kg of the toxin. Antamanide is a competitive inhibitor of the transport system for phallotoxins and amatoxins in the parenchyma cells of the liver [Ih. Wieland, Peptides of Poisonous Amanita Mushrooms, Springer Series in Molecular Biology, Springer Ver-lag, Berlin, New York, 1986 K. Munster etal., Biochem. Biophys. Acta 1986, 860,91]. 

The history of the major achievements concerning the isolation, structure elucidation, chemistry, and biological activity of the cyclic peptide principles of A. phalloides was comprehensively covered mainly by T. Wieland, a man of great merit particularly in this branch of natural products research. He dealt with the subject in several review articles 10,87,94,98-101) and more recently in an excellent book on the peptides of poisonous Amanita mushrooms 86). The number of references cited in the book exceeded 750, which gives a rough idea of the proportion of research carried out by chemists on this topic. The scope of the present chapter enables us only to summarize briefly the final results of these interesting studies. 

Th. Wieland, Peptides of poisonous Amanita mushrooms. A. Rich ed.. Springer Verlag, Berlin Heidelberg New York 1986... 

Contents Introduction. - Mushrooms Causing Death in Rare Cases. Deadly Poisonous Amanita Mushrooms and Their Constituents. - Toadstools Accumulating Amatoxins. - Poisoning by Amatoxins. - Two Centuries of Amanita Research. - Recognition,... 

The poison present in the fungus most commonly responsible for cases of poisoning. Amanita phalloides, is a peptide known as phalloidin. On hydrolysis, it gives cystine and alanine, but, in addition, allohydroxy-L-proline, a diastereoisomer of the form of proline found in proteins. 

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