This view shows enzymes only for those organisms listed below, in the list of taxa known to possess the pathway. If an enzyme name is shown in bold, there is experimental evidence for this enzymatic activity.
|Superclasses:||Biosynthesis → Secondary Metabolites Biosynthesis → Terpenoids Biosynthesis → Triterpenoids Biosynthesis|
Expected Taxonomic Range: Viridiplantae
Thousands of nonsteroidal triterpenes have been identified and, in spite of their elusive functions, the ubiquity of these compounds among higher plants implies that they are essential. Lupeol is a pentacyclic triterpene present in plants but not fungi and animals. Lupeol displays anti-inflammatory properties when administered to rats, yet, unlike other non-steroidal anti-inflammatory drugs, had no antinociceptive, anti-pyretic and ulcerogenic actions [Geetha01]. Lupeol was also reported to be involved in apoptosis [Aratanechemuge04].
Key Notes on the Enzymes:
Lupeol is synthesized by oxidosqualene cyclases from oxidosqualene. These enzymes catalyze the cyclization, rearrangement and deprotonation of oxidosqualene to simultaneously form a variety of triterpene compounds in varying amounts. The first lupeol synthase identified from Arabidopsis thaliana col was thus shown to catalyze the formation of -not only- lupeol but lupan-3β,20-diol, β-amyrin, germanicol, taraxasterol and Ψ-taraxasterol [Segura00].
Unification Links: AraCyc:PWY-112
Aratanechemuge04: Aratanechemuge Y, Hibasami H, Sanpin K, Katsuzaki H, Imai K, Komiya T (2004). "Induction of apoptosis by lupeol isolated from mokumen (Gossampinus malabarica L. Merr) in human promyelotic leukemia HL-60 cells." Oncol Rep 11(2);289-92. PMID: 14719056
Basyuni06: Basyuni M, Oku H, Inafuku M, Baba S, Iwasaki H, Oshiro K, Okabe T, Shibuya M, Ebizuka Y (2006). "Molecular cloning and functional expression of a multifunctional triterpene synthase cDNA from a mangrove species Kandelia candel (L.) Druce." Phytochemistry 67(23);2517-24. PMID: 17078982
Guhling06: Guhling O, Hobl B, Yeats T, Jetter R (2006). "Cloning and characterization of a lupeol synthase involved in the synthesis of epicuticular wax crystals on stem and hypocotyl surfaces of Ricinus communis." Arch Biochem Biophys 448(1-2);60-72. PMID: 16445885
HusselsteinMull01: Husselstein-Muller T, Schaller H, Benveniste P (2001). "Molecular cloning and expression in yeast of 2,3-oxidosqualene-triterpenoid cyclases from Arabidopsis thaliana." Plant Mol Biol 45(1);75-92. PMID: 11247608
Shibuya07: Shibuya M, Xiang T, Katsube Y, Otsuka M, Zhang H, Ebizuka Y (2007). "Origin of structural diversity in natural triterpenes: direct synthesis of seco-triterpene skeletons by oxidosqualene cyclase." J Am Chem Soc 129(5);1450-5. PMID: 17263431
Zhang03b: Zhang H, Shibuya M, Yokota S, Ebizuka Y (2003). "Oxidosqualene cyclases from cell suspension cultures of Betula platyphylla var. japonica: molecular evolution of oxidosqualene cyclases in higher plants." Biol Pharm Bull 26(5);642-50. PMID: 12736505
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