Illudin S

The illudins are a family of sesquiterpenes with antitumor antibiotic properties produced by some mushrooms. In their isolated form, illudins show selective toxicity for myelocytic leukemia and other carcinoma cells.

Illudin is highly toxic, with little apparent therapeutic value in its natural form. It is thought responsible for the ill effects caused by various Omphalotus species like O. olearius and O. illudens (Jack 'o' Lantern mushrooms), and O. nidiformis (Australian ghost fungus).

Inside cells, illudin is chemically changed to react with DNA, thus creating an unknown type of DNA damage that blocks the transcription process. This block can only be relieved by the DNA repair system nucleotide excision repair. Damages in non-transcribed DNA areas are ignored. This property was exploited by the company MGI Pharma to develop an illudin-derivative called Irofulven for use as an anti-cancer medicine. Its application is still in the experimental phase.

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