Sesquiterpene lactones from Artemisia lucentica

Marco, J. Alberto; Sanz‐Cervera, Juan F.; García-Lliso, Vicente; Batlle, Natalia

doi:10.1016/s0031-9422(97)00029-0

Cited by 22 publications

(17 citation statements)

References 21 publications

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“…The epimeric 3-hydroxycamphors were shown to be resolved when analysed by enantioselective GC (cyclodextrin), with 5 eluting first.Pool 2 was found to contain only 6-endo-hydroxycamphor 7, characteristically displaying a hydroxmethine at  H 4.14 ppm (ddd J 9.5, 2.5, 1 Hz, H6), the smallest coupling corresponding to long range coupling to H4. This assignment was confirmed by the correspondence of 1 H and 13 C data with literature data (ESI) [28,34].…”

supporting

confidence: 79%

An in vivo cytochrome P450cin (CYP176A1) catalytic system for metabolite production

Slessor¹,

Hawkes²,

Farlow³

et al. 2012

Journal of Molecular Catalysis B: Enzymatic

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Cytochrome P450 cin (CYP176A1) is a bacterial P450 isolated from Citrobacter braakii that catalyses the hydroxylation of 1,8-cineole to (1R)-6β-hydroxycineole. P450 cin uses two redox partners in vitro for catalysis: cindoxin, its physiological FMN-containing redox partner, and Escherichia coli flavodoxin reductase. Here we report the construction of a tricistronic plasmid that expresses P450 cin , cindoxin and E. coli flavodoxin reductase and a bicistronic plasmid that encodes only P450 cin and cindoxin. E. coli transformed with the bicistronic vector effectively catalysed the oxidation of 1,8-cineole, with the endogenous E. coli flavodoxin reductase presumably acting as the terminal electron transfer protein. This in vivo system was capable of producing enantiomerically pure (1R)-6β-hydroxycineole in yields of ~1 g/L culture, thus providing a simple, one-step synthesis of this compound. In addition, the metabolism of (1R)-and (1S)-camphor, structural homologues of 1,8-cineole was also evaluated in order to investigate the ability of this in vivo system to produce compounds for mechanistic studies. Significant quantities of five of the six possible secondary alcohols arising from methylene oxidation of both (1R)-and (1S)-camphor were isolated and structurally characterised. The similarity of the (1R)-and (1S)camphor product profiles highlight the importance of the inherent reactivity of the substrate in determining the regiochemistry of oxidation in the absence of any specific enzyme-substrate binding interactions.

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supporting

confidence: 79%

An in vivo cytochrome P450cin (CYP176A1) catalytic system for metabolite production

Slessor¹,

Hawkes²,

Farlow³

et al. 2012

Journal of Molecular Catalysis B: Enzymatic

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“…The genus Artemisia has been the object of numerous chemical studies (Marco et al, 1994a(Marco et al, , 1994bYasphe et al, 1987;Kim, 1996;Kil et al, 1991). There are large amounts of monoterpenoids and their derivates in Artemisia species (Ahmad and Misra, 1994).…”

mentioning

confidence: 99%

Variation of monoterpenoids inartemisia feddei andArtemisia scoparia

Kim

1997

J. Plant Biol.

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The composition and concentration of monoterpenoids in the leaves and stems of Artemisia feddei and Artemisia scoparia were determined, and seasonal variation in the monoterpenoids of Artemisia species were investigated. The two species possessed different compositions and concentrations of monoterpenoids. The total amount of monoterpenoid in A. scoparia was always higher than that of A. feddei, and the monoterpenoid yields of leaves were higher than stem yields in both species as compounds formed. The major constituents of A. scoparia were 25 while A. feddei consisted of 26 compounds. Sixteen common monoterpenoid compounds were found in both plants. Large differences in the relative amounts of the monoterpenoids were found between species and seasons. Extremely large differences in the relative amounts of naphtalene, sabinene, ~-pinene, cyclohexene, and octatrine were found in the leaf monoterpenoids of the two species. The largest differences in relative amounts of stem monoterpenoids were in s abinene and lS-pinene levels.

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“…Camphor ( 38 ) was also identified as a substrate for CYP154E1, although conversion was low (5 %) and with a single reaction product. The EI mass spectrum did not match hydroxylation at the 5‐position (as described for CYP101 enzymes) but displayed high similarity (match factor 791) to a published mass spectrum of 6‐hydroxy camphor 17…”

Section: Resultsmentioning

confidence: 80%

Cluster Screening: An Effective Approach for Probing the Substrate Space of Uncharacterized Cytochrome P450s

2013

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Cytochrome P450 monooxygenases (P450s) are versatile enzymes with high potential for biocatalysis. The number of newly annotated P450 genes has been increasing constantly, and these thus represent a rich resource for new biocatalysts. However, the substrate scopes of newly identified P450s are often not known, and thus their exploitation is difficult. Herein we describe an approach, named "cluster screening", and its application for the primary characterization of two P450s: CYP154E1 and CYP154A8. A library comprising 51 compounds was designed and organized into nine groups according to their chemical properties. The activities of both P450s in vitro were maintained with suitable nonphysiological redox partners, and the cluster library was screened with these enzymes for product formation. From this library, 30 compounds tested positive for CYP154E1 and 23 were positive for CYP154A8. Cluster screening distinguishes subtle differences in activity and selectivity of enzymes as closely related as those of the same P450 family. For example, the alkaloid pergolide mesylate was converted by CYP154E1 (4 %) but not by CYP154A8. A building block of vitamin D3 , Grundmann's ketone, was converted by both enzymes, although conversion was higher with CYP154E1 (100 vs 53%).

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Sesquiterpene lactones from Artemisia lucentica

Cited by 22 publications

References 21 publications

An in vivo cytochrome P450cin (CYP176A1) catalytic system for metabolite production

An in vivo cytochrome P450cin (CYP176A1) catalytic system for metabolite production

Variation of monoterpenoids inartemisia feddei andArtemisia scoparia

Cluster Screening: An Effective Approach for Probing the Substrate Space of Uncharacterized Cytochrome P450s

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