Fungal toxin synthesis

Cundliffe, E., Cannon, M., and Davies, J. (1974). Mechanism of inhibition of eukaryotic protein synthesis b trichothecene fungal toxins. Proc. Natl. Acad. Sci. USA 71, 30-34. 

S)-(+)-Carvone (17) has itself served as the starting material in the synthesis of the tricyclic lactone, eucannabinolide (18)(ref.17) and in that of the wheat plant fungal toxin helminthospoal (19) (ref.18). By contrast,(R)-(-)-carvone has been engaged as the intermediate for the formation of the epoxydilactone, picrotoxinin (20) (ref.19). 

Several specific enzyme activities associated with precursor conversions in the aflatoxin pathway " " have been partially purified (Fig.l 1.1) whereas others such as methyltransferases " have been purified to homogeneity. Several other enzymes involved in aflatoxin biosynthesis, such as a reductase and a cyclase, " have also been purified from A. parasiticus. A desaturase that converts VERA to VERB has been found in cell-free fungal extracts. Matsushima et al. have purified and characterized two versiconal hemiacetal acetate reductases involved in toxin synthesis, whereas Kusumoto and Hsieh purified to homogeneity an esterase that converts VHA to versiconal. ... 

The relative stereochemistry of the fungal toxins AK-I and -II was established by the synthesis of the pair of epoxides (32) from L-... 

Weinreb and co-workers have applied the im/Wu-Diels-Alder reaction to a synthesis of streptonigrin (81), and also the intramolecular variant of the same reaction in a neat synthesis of the fungal toxin slaframine (82). In addition, full details of Martin s formal synthesis of lycorine (85), based on the intramolecular Diels-Alder reaction (83) -> (84), have now been published. ... 

CuNDLiFFE, E., and J. E. Davies Inhibition of initiation, elongation and termination of eukaryotic protein synthesis by trichothecene fungal toxins. Antimicrob. Agents Chemother. 11, 491 (1977). 

The synthesis of the fungal wheat plant toxin helminthosporal is referred to in Sections 3.1 and 5.2 of Part One. 

Trichothecene mycotoxin Toxin produced by fungal molds it inhibits protein synthesis, impairs DNA synthesis, and interferes with cell membrane structure and function. 

A microreview on recent advances in the total synthesis of chloro-sulfolipids has been published by Nilewski and Carreira a comprehensive section has been devoted to /-based configuration analysis of these compounds. A review on relationship between stereochemistry and biological activity of fungal phytotoxins has been written by Evidente et al The authors indicate that in many cases NMR spectroscopy, in particular /hh and /hc couplings, was a useful source of information on the relative and/or absolute configuration of these toxins produced by pathogenic fungi. 

Figure I Primary structure of bacterial (I) and fungal (II) peptide antibiotics that are synthesized by the noniibosomal thiotemplatc mechanism. (I) (a) gramicidin S, (b) tyrocidine, (c) surfactin. (d) bacitracin (II) (a) HC-toxin, (b) enniatin A. (c) cyclosporin A. The amino acid sequence of the peptides is shown, as are the names of the enzymes that catalyze synthesis. The otder of incorporation is indicated by the anows, beginning with the amino acid shown below the name of the enzyme subunit.

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