parkeol

lanost-9(11)-en-3 beta-ol (3S,5R,8S,10S,13R,14S,17R)-4,4,10,13,14- pentamethyl-17-[(2R)-6-methylhept-5-en-2-yl]-2,3,5,6,7,8,12,15,16,17-decahydro-1H-cyclopenta[a]phenanthren-3-ol PubMed: Identification of key amino acid residues determining product specificity of 2,3-oxidosqualene cyclase in Oryza species. PubMed: Deficiency of a triterpene pathway results in humidity-sensitive genic male sterility in rice. PubMed: Control of the 1,2-rearrangement process by oxidosqualene cyclases during triterpene biosynthesis. PubMed: Catalytic mechanism and product specificity of oxidosqualene-lanosterol cyclase: a QM/MM study. PubMed: Protein engineering of Saccharomyces cerevisiae oxidosqualene-lanosterol cyclase into parkeol synthase. PubMed: Divergent evolution of oxidosqualene cyclases in plants. PubMed: Triterpene cyclases from Oryza sativa L.: cycloartenol, parkeol and achilleol B synthases. PubMed: Triterpene alcohol and fatty acid composition of shea nuts from seven African countries. PubMed: Protostadienol synthase from Aspergillus fumigatus: functional conversion into lanosterol synthase. PubMed: Formation of triterpenoids throughout Olea europaea fruit ontogeny. PubMed: Site-saturated mutagenesis of histidine 234 of Saccharomyces cerevisiae oxidosqualene-lanosterol cyclase demonstrates dual functions in cyclization and rearrangement reactions. PubMed: Tryptophan 232 within oxidosqualene-lanosterol cyclase from Saccharomyces cerevisiae influences rearrangement and deprotonation but not cyclization reactions. PubMed: Plant lanosterol synthase: divergence of the sterol and triterpene biosynthetic pathways in eukaryotes. PubMed: Phylogenetic and biochemical evidence for sterol synthesis in the bacterium Gemmata obscuriglobus. PubMed: Directed evolution experiments reveal mutations at cycloartenol synthase residue His477 that dramatically alter catalysis. PubMed: Oxidosqualene Cyclase Residues that Promote Formation of Cycloartenol, Lanosterol, and Parkeol We are grateful to Bridget M. Joubert for advice regarding mutagenesis. We thank Elizabeth A. Hart for an authentic parkeol standard, and for chromatographic and spectroscopic information. This research was funded by the National Institutes of Health (grant no. AI 41598) and the Robert A. Welch Foundation (grant no. C-1323). M.M.M. was an American Society of Pharmacognosy Undergraduate Fellow. M.J.R.S. was a Robert A. Welch Fellow and was supported by an NIH Biotechnology Training Grant (grant no. T32 GM08362). PubMed: Steric bulk at cycloartenol synthase position 481 influences cyclization and deprotonation. PubMed: In vivo and in vitro biosynthesis of saponins in sea cucumbers. PubMed: Biosynthetic studies of marine lipids. 42. Biosynthesis of steroid and triterpenoid metabolites in the sea cucumber Eupentacta fraudatrix. PubMed: Sterol biosynthesis via cycloartenol and other biochemical features related to photosynthetic phyla in the amoeba Naegleria lovaniensis and Naegleria gruberi. PubMed: Biogenetic-type total synthesis. 24,25-Dihydrolanosterol, 24,25-dihydro- 13(17) -protosterol, isoeuphenol, (-)-isotirucallol, and parkeol. PubMed: The conversion of parkeol into its 24,25-epoxide by tissue cultures of Nicotiana tabacum. PubMed: [Synthesis of labeled tetracyclic triterpenes. I. Lanosterol, cycloartenol, parkeol and 31-norcycloartenol(25-14C) or (26,27-D). II. Lanosterol and cycloartenol (2-T)]. PubMed: Studies in phytosterol biosynthesis. Mechanism of biosynthesis of cycloartenol.