Ethionine is an antimetabolite and methionine antagonist. It prevents amino acid incorporation into proteins and interferes with cellular use of adenosine triphosphate (ATP). Because of these pharmacological effects, ethionine is highly toxic and is a potent carcinogen.[1]
Ethionine has been found to naturally occur in the edible pulp of the durian fruit, and postulated to be a biosynthetic precursor for ethanethiol and other strong odorants found in the fruit.[2]
References
^Narayan Shivapurkar, Mary J. Wilson and Lionel A. Poirier (1984). "Hypomethylation of DNA in ethionine-fed rats". Carcinogenesis. 5 (8): 989–992. doi:10.1093/carcin/5.8.989. PMID6744518.
^Nadine S. Fischer and Martin Steinhaus (2020). "Identification of an Important Odorant Precursor in Durian: First Evidence of Ethionine in Plants". Journal of Agricultural and Food Chemistry. 68 (38): 10397–10402. doi:10.1021/acs.jafc.9b07065. PMID31825619. S2CID209329891.