Atropa belladonna
Datura
Engineering tropane biosynthetic pathway in Hyoscyamus niger hairy root cultures. (1/10)
Scopolamine is a pharmaceutically important tropane alkaloid extensively used as an anticholinergic agent. Here, we report the simultaneous introduction and overexpression of genes encoding the rate-limiting upstream enzyme putrescine N-methyltransferase (PMT) and the downstream enzyme hyoscyamine 6 beta-hydroxylase (H6H) of scopolamine biosynthesis in transgenic henbane (Hyoscyamus niger) hairy root cultures. Transgenic hairy root lines expressing both pmt and h6h produced significantly higher (P < 0.05) levels of scopolamine compared with the wild-type and transgenic lines harboring a single gene (pmt or h6h). The best line (T(3)) produced 411 mg/liter scopolamine, which was over nine times more than that in the wild type (43 mg/liter) and more than twice the amount in the highest scopolamine-producing h6h single-gene transgenic line H(11) (184 mg/liter). To our knowledge, this is the highest scopolamine content achieved through genetic engineering of a plant. We conclude that transgenic plants harboring both pmt and h6h possessed an increased flux in the tropane alkaloid biosynthetic pathway that enhanced scopolamine yield, which was more efficient than plants harboring only one of the two genes. It seems that the pulling force of the downstream enzyme (the faucet enzyme) H6H plays a more important role in stimulating scopolamine accumulation in H. niger whereas the functioning of the upstream enzyme PMT is increased proportionally. This study provides an effective approach for large-scale commercial production of scopolamine by using hairy root culture systems as bioreactors. (+info)Amino acid sequences of ferredoxins from Atropa belladonna and Hyoscyamus niger: their similarities to those in other tropane-alkaloid-containing plants. (2/10)
The complete amino acid sequences of [2Fe-2S] ferredoxin from Atropa belladonna and Hyoscyamus niger have been determined by automated Edman degradation of the entire S-carboxymethylcysteinyl proteins and of the peptides obtained by enzymatic digestion. These two ferredoxins exhibited 1-8 differences in their amino acid sequences compared to those of other tropane-alkaloid-containing plants (Scopolia japonica, Datura stramonium, D. metel, and D. arborea), and only 1 or 4 differences compared to S. japonica and D. arborea. In contrast, 9-23 differences were observed among the other solanaceous ferredoxins. This suggests that tropane-alkaloid-containing plants are closely related taxonomically. (+info)Stereochemistry and deuterium isotope effects associated with the cyclization-rearrangements catalyzed by tobacco epiaristolochene and hyoscyamus premnaspirodiene synthases, and the chimeric CH4 hybrid cyclase. (3/10)
Tobacco epiaristolochene and hyoscyamus premnaspirodiene synthases (TEAS and HPS) catalyze the cyclizations and rearrangements of (E,E)-farnesyl diphosphate (FPP) to the corresponding bicyclic sesquiterpene hydrocarbons. The complex mechanism proceeds through a tightly bound (R)-germacrene A intermediate and involves partitioning of a common eudesm-5-yl carbocation either by angular methyl migration, or by C-9 methylene rearrangement, to form the respective eremophilane and spirovetivane structures. In this work, the stereochemistry and timing of the proton addition and elimination steps in the mechanism were investigated by synthesis of substrates bearing deuterium labels in one or both terminal methyl groups, and in the pro-S and pro-R methylene hydrogens at C-8. Incubations of the labeled FPPs with recombinant TEAS and HPS, and with the chimeric CH4 hybrid cyclase having catalytic activities of both TEAS and HPS, and of unlabeled FPP in D2O, together with gas chromatography-mass spectrometry (GC-MS) and/or NMR analyses of the labeled products gave the following results: (1) stereospecific CH3-->CH2 eliminations at the cis-terminal methyl in all cases; (2) similar primary kinetic isotope effects (KIE) of 4.25-4.64 for the CH3-->CH2 eliminations; (3) a significant intermolecular KIE (1.33+/-0.03) in competitive cyclizations of unlabeled FPP and FPP-d6 to premnaspirodiene by HPS; (4) stereoselective incorporation of label from D2O into the 1beta position of epiaristolochene; (5) stereoselective eliminations of the 1beta and 9beta protons in formation of epiaristolochene and its delta(1(10)) isomer epieremophilene by TEAS and CH4; and (6) predominant loss of the 1alpha proton in forming the cyclohexene double bond of premnaspirodiene by HPS and CH4. The results are explained by consideration of the conformations of individual intermediates, and by imposing the requirement of stereoelectronically favorable proton additions and eliminations. (+info)Some Lithuanian ethnobotanical taxa: a linguistic view on thorn apple and related plants. (4/10)
BACKGROUND: The perception and use of plants correspond with common plant names. The study of plant names may give insight into historical and recent use of plants. METHODS: Plant names in dictionaries and folklore have been evaluated. A etymological analysis of the names is provided. Onomasiological and semasiological aspects have been considered. Therefore, species named with names related to each other have been selected. RESULTS: Plant names containing the stem dag- or deg- may belong to either of two categories: incenses or thorny plants. Plants named in durn- have been in use as psychopharmaca. The name rymo points not to Rome but to the use of plants as anodyne or psychopharmaca. (+info)Hyosgerin, a new optically active coumarinolignan, from the seeds of Hyoscyamus niger. (5/10)
Hyosgerin, a new optically active coumarinolignan, has been isolated and characterized along with three other coumarinolignans, venkatasin, cleomiscosin A and cleomiscosin B, from the seeds of Hyoscyamus niger L. The structure was determined on the basis of spectroscopic analysis and chemical conversion. The optical properties and absolute stereochemistry of these coumarinolignans have also been studied and discussed. (+info)Functional genomic analysis of alkaloid biosynthesis in Hyoscyamus niger reveals a cytochrome P450 involved in littorine rearrangement. (6/10)
Tropane alkaloids are valuable pharmaceutical drugs derived from solanaceous plants such as Hyoscyamus niger (black henbane). The biosynthesis of these molecules, including the nature of the enigmatic rearrangement of (R)-littorine to (S)-hyoscyamine, is not completely understood. To test the hypothesis that a cytochrome P450 enzyme is involved in this rearrangement, we used virus-induced gene silencing to silence a cytochrome P450, CYP80F1, identified from H. niger roots by EST sequencing. Silencing CYP80F1 resulted in reduced hyoscyamine levels and the accumulation of littorine. Hyoscyamine was observed in CYP80F1-expressing tobacco hairy roots supplied with (R)-littorine. Expression in yeast confirmed that CYP80F1 catalyzes the oxidation of (R)-littorine with rearrangement to form hyoscyamine aldehyde, a putative precursor to hyoscyamine, and without rearrangement to form 3'-hydroxylittorine. Our data strongly support the involvement of CYP80F1 in the rearrangement of littorine to hyoscyamine. (+info)Functional characterization of premnaspirodiene oxygenase, a cytochrome P450 catalyzing regio- and stereo-specific hydroxylations of diverse sesquiterpene substrates. (7/10)
Solavetivone, a potent antifungal phytoalexin, is derived from a vetispirane-type sesquiterpene, premnaspirodiene, by a putative regio- and stereo-specific hydroxylation, followed by a second oxidation to yield the alpha,beta-unsaturated ketone. Mechanistically, these reactions could occur via a single, multifunctional cytochrome P450 or some combination of cytochrome P450s and a dehydrogenase. We report here the characterization of a single cytochrome P450 enzyme, Hyoscyamus muticus premnaspirodiene oxygenase (HPO), that catalyzes these successive reactions at carbon 2 (C-2) of the spirane substrate. HPO also catalyzes the equivalent regio-specific (C-2) hydroxylation of several eremophilane-type (decalin ring system) sesquiterpenes, such as with 5-epi-aristolochene. Moreover, HPO displays interesting comparisons to other sesquiterpene hydroxylases. 5-Epi-aristolochene di-hydroxylase (EAH) differs catalytically from HPO by introducing hydroxyl groups first at C-1, then C-3 of 5-epi-aristolochene. HPO and EAH also differ from one another by 91-amino acid differences, with four of these differences mapping to putative substrate recognition regions 5 and 6. These four positions were mutagenized alone and in various combinations in both HPO and EAH and the mutant enzymes were characterized for changes in substrate selectivity, reaction product specificity, and kinetic properties. These mutations did not alter the regio- or stereo-specificity of either HPO or EAH, but specific combinations of the mutations did improve the catalytic efficiencies 10-15-fold. Molecular models and comparisons between HPO and EAH provide insights into the catalytic properties of these enzymes of specialized metabolism in plants. (+info)Flow cytometric investigations of diploid and tetraploid plants and in vitro cultures of Datura stramonium and Hyoscyamus niger. (8/10)
(+info)Hyoscyamus is the genus name for a group of plants commonly known as Henbane. These plants belong to the Solanaceae family, which also includes nightshade, tobacco, and potato. Hyoscyamus niger, or black henbane, is the species most commonly referred to in a medical context.
The plants contain various alkaloids, including scopolamine, hyoscine (also known as atropine), and hyoscyamine. These substances can have medicinal applications but are also highly toxic in large amounts. They can affect the nervous system, causing delirium, hallucinations, and other symptoms.
In a medical context, 'Hyoscyamus' may also refer to medications that contain alkaloids derived from these plants. These are used primarily to treat gastrointestinal disorders, as they can reduce gastric secretions and have antispasmodic effects. However, due to their potential for serious side effects, including hallucinations and cardiac problems, these medications are typically used only when other treatments have not been effective.
'Atropa belladonna' is a plant species that is commonly known as deadly nightshade. It belongs to the family Solanaceae and is native to Europe, North Africa, and Western Asia. The plant contains powerful toxic alkaloids, including atropine, scopolamine, and hyoscyamine, which can have various pharmacological effects on the human body.
Atropa belladonna has been used in medicine for its anticholinergic properties, which include blocking the action of the neurotransmitter acetylcholine in the nervous system. This effect can be useful in treating conditions such as Parkinson's disease, gastrointestinal disorders, and respiratory problems. However, due to its high toxicity, the use of Atropa belladonna and its alkaloids is closely regulated and requires medical supervision.
It is important to note that all parts of the plant, including the berries and leaves, are highly toxic and can cause serious harm or death if ingested or otherwise introduced to the body. Therefore, it is essential to exercise caution when handling this plant and to seek immediate medical attention if exposure occurs.
'Datura' is a genus of plants that belong to the family Solanaceae, also known as nightshades. These plants are native to North and South America but have been introduced and naturalized in many parts of the world. Some common names for plants in this genus include Jimson weed, thorn apple, and angel's trumpet.
Datura species contain a variety of toxic alkaloids, including scopolamine, atropine, and hyoscyamine, which can have hallucinogenic effects when ingested. However, these plants are also highly poisonous and can cause serious harm or death if consumed. Ingesting even small amounts can result in symptoms such as dilated pupils, dry mouth, rapid heartbeat, confusion, agitation, and delirium.
It is worth noting that Datura is sometimes used in traditional medicine practices, but it should only be administered under the close supervision of a qualified healthcare provider, as improper use can lead to severe adverse effects.
"Solanaceae" is not a medical term but a taxonomic category in biology, referring to the Nightshade family of plants. This family includes several plants that have economic and medicinal importance, as well as some that are toxic or poisonous. Some common examples of plants in this family include:
- Solanum lycopersicum (tomato)
- Solanum tuberosum (potato)
- Capsicum annuum (bell pepper and chili pepper)
- Nicotiana tabacum (tobacco)
- Atropa belladonna (deadly nightshade)
- Hyoscyamus niger (henbane)
While Solanaceae isn't a medical term itself, certain plants within this family have medical significance. For instance, some alkaloids found in these plants can be used as medications or pharmaceutical precursors, such as atropine and scopolamine from Atropa belladonna, hyoscine from Hyoscyamus niger, and capsaicin from Capsicum species. However, it's important to note that many of these plants also contain toxic compounds, so they must be handled with care and used only under professional supervision.