Parkeol Explained

Parkeol is a relatively uncommon sterol secondary metabolite found mostly in plants, particularly noted in Butyrospermum parkii (now called Vitellaria paradoxa, or the shea tree).^[1] It can be synthesized as a minor product by several oxidosqualene cyclase enzymes, and is the sole product of the enzyme parkeol synthase.^[2]

Parkeol is the dominant sterol found in the planctomycete Gemmata obscuriglobus, a rare example of a sterol-synthesizing prokaryote. The only other sterol identified in this organism is lanosterol, a key component of the sterol biosynthetic pathway in animals and fungi; this relatively limited sterol repertoire may resemble the early evolution of sterol synthesis, which is ubiquitous in eukaryotes.^[3]

Notes and References

1. Itoh. Toshihiro. Uetsuki. Toshimitsu. Tamura. Toshitake. Matsumoto. Taro. Characterization of triterpene alcohols of seed oils from some species of theaceae, phytolaccaceae and sapotaceae. Lipids. June 1980. 15. 6. 407–411. 10.1007/BF02534064. 25505422.
2. Ito. R. Mori. K. Hashimoto. I. Nakano. C. Sato. T. Hoshino. T. Triterpene cyclases from Oryza sativa L.: cycloartenol, parkeol and achilleol B synthases.. Organic Letters. 20 May 2011. 13. 10. 2678–81. 21526825. 10.1021/ol200777d.
3. Pearson. A. Budin. M. Brocks. JJ. Phylogenetic and biochemical evidence for sterol synthesis in the bacterium Gemmata obscuriglobus.. Proceedings of the National Academy of Sciences of the United States of America. 23 December 2003. 100. 26. 15352–7. 14660793. 10.1073/pnas.2536559100. 307571. 2003PNAS..10015352P. free.