62235-06-7Relevant articles and documents
Substrate Requirements for Lepidopteran Farnesol Dehydrogenase
Sen, Stephanie E.,Garvin, Gail M.
, p. 820 - 825 (1995)
Farnesol dehydrogenase of the lepidopteran Manduca sexta shows surprisingly high substrate specificity, as inferred from the binding of substrate analogs and (potential) alternative substrates.The enzyme is not a simple alcohol dehydrogenase, as ethanol and octanol are not substrates for this enzyme.The enzyme also does not appear to be related to Drosophila alcohol dehydrogenase since secondary alcohols are much poorer inhibitors.Several farnesol analogs with modified carbon skeletons have been tested for their ability to function as inhibitors of farnesoldehydrogenase.Substrate competition studies indicate that the enzyme is highly specific for alcohols with Δ-2,3 unsaturation, trans allylic olefin geometry, and alkyl chain hydrophobicity corresponding to at least three isoprene units.These results suggest that farnesol dehydrogenase is a unique dehydrogenase that should be further examined as a potential target for anti juvenoid development.Keywords: Farnesol dehydrogenase; juvenile hormone biosynthesis; Manduca sexta; substrate analogs
Herbivore-induced and floral homoterpene volatiles are biosynthesized by a single P450 enzyme (CYP82G1) in Arabidopsis
Lee, Sungbeom,Badieyan, Somayesadat,Bevan, David R.,Herde, Marco,Gatz, Christiane,Tholl, Dorothea
scheme or table, p. 21205 - 21210 (2011/10/04)
Terpene volatiles play important roles in plant-organism interactions as attractants of pollinators or as defense compounds against herbivores. Among the most common plant volatiles are homoterpenes, which are often emitted from night-scented flowers and from aerial tissues upon herbivore attack. Homoterpene volatiles released from herbivore-damaged tissue are thought to contribute to indirect plant defense by attracting natural enemies of pests. Moreover, homoterpenes have been demonstrated to induce defensive responses in plant-plant interaction. Although early steps in the biosynthesis of homoterpenes have been elucidated, the identity of the enzyme responsible for the direct formation of these volatiles has remained unknown. Here, we demonstrate that CYP82G1 (At3g25180), a cytochrome P450 monooxygenase of the Arabidopsis CYP82 family, is responsible for the breakdown of the C20-precursor (E,E)-geranyllinalool to the insect-induced C16-homoterpene (E,E)-4,8,12-trimethyltrideca-1,3,7,11-tetraene (TMTT). Recombinant CYP82G1 shows narrow substrate specificity for (E,E)- geranyllinalool and its C 15-analog (E)-nerolidol, which is converted to the respective C 11-homoterpene (E)-4,8-dimethyl-1,3,7-nonatriene (DMNT). Homology-based modeling and substrate docking support an oxidative bond cleavage of the alcohol substrate via syn-elimination of the polar head, together with an allylic C-5 hydrogen atom. CYP82G1 is constitutively expressed in Arabidopsis stems and inflorescences and shows highly coordinated herbivoreinduced expression with geranyllinalool synthase in leaves depending on the F-box protein COI-1. CYP82G1 represents a unique characterized enzyme in the plant CYP82 family with a function as a DMNT/TMTT homoterpene synthase.
Olefination and hydroxymethylation of aldehydes using Knochel's (dialkoxyboryl)methylcopper reagents
Sakai, Masaaki,Saito, Syunn,Kanai, Gen,Suzuki, Akira,Miyaura, Norio
, p. 915 - 924 (2007/10/03)
The in-situ preparation of [(Me2C)2O2BCH2]Cu(CN)ZnI (3) from Knochel's (dialkoxyboryl)-methylzinc reagent (2) and CuCN·2LiCl in THF, followed by its addition to aldehyde in the presence of boron trifluoride etherate yielded rather stable β-hydroxyalkylboronates (5). The thermal dehydroxyboronation or the alkaline hydrogen peroxide oxidation of 5 gave the corresponding alkenes (6) or 1,2-alkanediols (7) in high yields. The reaction provides a simple procedure for the olefination or the hydroxymethylation of aldehydes.