Strictosidine synthase, an indispensable enzyme involved in the biosynthesis of terpenoid indole and β-carboline alkaloids / 中国天然药物

Terpenoid indole (TIAs) and β-carboline alkaloids (BCAs), such as suppressant reserpine, vasodilatory yohimbine, and antimalarial quinine, are natural compounds derived from strictosidine. These compounds can exert powerful pharmacological effects but be obtained from limited source in nature. the whole biosynthetic pathway of TIAs and BCAs, The Pictet-Spengler reaction catalyzed by strictosidine synthase (STR; EC: 4.3.3.2) is the rate-limiting step. Therefore, it is necessary to investigate their biosynthesis pathways, especially the role of STR, and related findings will support the biosynthetic generation of natural and unnatural compounds. This review summarizes the latest studies concerning the function of STR in TIA and BCA biosynthesis, and illustrates the compounds derived from strictosidine. The substrate specificity of STR based on its structure is also summarized. Proteins that contain six-bladed four-stranded β-propeller folds in many organisms, other than plants, are listed. The presence of these folds may lead to similar functions among organisms. The expression of STR gene can greatly influence the production of many compounds. STR is mainly applied to product various valuable drugs in plant cell suspension culture and biosynthesis in other carriers.

Biosíntesis de alcaloides bencilisoquinolínicos / Benzylisoquinoline alkaloid biosynthesis / Biossíntese de alcalóides benzilisoquinolinas

Los alcaloides bencilisoquinolínicos (ABI) son metabolitos especializados con una distribución filogenética antigua pero conservadatodavía en clados modernos. Varios de ellos, como la morfina, sanguinerina y berberina tienen importancia en la medicina moderna. Enesta revisión se analizan los aspectos más sobresalientes del estado actual de la biosíntesis de ABI. Se han realizado estudios que hanpermitido conocer la biosíntesis de 22 de estos metabolitos nitrogenados. En su formación participan 43 enzimas agrupadas en oxidoreductasas,transferasas y liasas, que en algunos casos representan ejemplos atípicos de la forma en la que se originó la diversificación delmetabolismo secundario, entre ellos proteínas citocromo P450 (CYP450) con actividades catalíticas para la ruta de los ABI, o la enzimanorcoclaurina sintasa (NCS) que esta emparentada con proteínas alergénicas de defensa. Así mismo, hay avances genéticos en los quese ha podido caracterizar 30 enzimas, permitiendo conocer procesos de regulación. Otro aspecto interesante es la compartimentaciónde los sitios de biosíntesis y acumulación de ABI ya que en varios casos están separados espacialmente y en distintas especies o en lamisma pueden participar varios tipos de células. Ello ha sugerido el transporte intra e intercelular de los alcaloides, los precursores yde las enzimas, se ha documentado el transporte de berberina entre el citoplasma y las vacuolas del almacenamiento. El panorama de labiosíntesis de ABI se ha construido con los estudios de ejemplares de importancia farmacológica...

The benzylisoquinoline alkaloids (BIA) are specialized metabolites with an ancient phylogeneticdistribution, but still preserved in modern clades. Some of them, such as morphine, sanguinerine or berberine, are important for modernmedicine. This review discusses the highlights of the current state of the biosynthesis of BIA. There have been studies that show thebiosynthesis of 22 of these nitrogenous metabolites. In their formation there are 43 enzymes grouped into oxidoreductases, transferasesand lyases, which in some cases represent atypical examples of the manner in which the secondary metabolism diversification wasoriginated. Two of these examples are the cytochrome proteins P450 (P450), with catalytic activities for ABI route, or the norcoclaurinesynthase enzyme (NCS), which share substantial identity with defense allergenic proteins. Likewise, there are genetic advances thathave produced the characterization of 30 enzymes, allowing knowledge of regulatory processes. Another interesting aspect is thecompartmentation of the biosynthesis sites and accumulation of BIA, since in several cases they are spatially separated and in differentspecies, or in the same species several types of cells may be involved. This has suggested intra and intercellular transport of alkaloids,precursors and enzymes, and it has been documented berberine transport between the cytoplasm and the vacuoles of storage. The picturefor the biosynthesis of BIA has been constructed with exemplary studies of alkaloids with pharmacological importance...

Os alcalóides benzilisoquinolinas (ABI) são metabólitos especializados com umadistribuição filogenética antiga, mas ainda preservada em clados modernos. Vários deles, como a morfina, sanguinarina e berberina sãoimportantes na medicina moderna. Neste artigo, se analisam os aspectos mais destacados do estado atual da biossíntese de ABI; há estudosque tem permitido conhecer a biossíntese de 22 desses metabólitos nitrogenados. Na sua síntese participam 43 enzimas agrupadas emoxidoreductases, transferases, liases e, em alguns casos, representam exemplos atípicos da forma pela qual se originou a diversificaçãodo metabolismo secundário, incluindo as proteínas do citocromo P450 (CYP450), com atividades catalíticas para a rota dos ABI, ou aenzima norcoclaurina sintase (NCS), que está relacionada com proteínas alergênicas de defesa. Da mesma forma, há avanços genéticosna caracterização de 30 enzimas, permitindo conhecer processos de regulação. Outro aspecto interessante é a compartimentalização dossítios de biossíntese e acumulação de ABI uma vez que em muitos casos estão separados espacialmente e em diferentes espécies, ou namesma podem participar vários tipos de células. Isto há sugerido o transporte intra e intercelular de alcalóides, precursores das enzimas;tem sido documentado o transporte de berberina entre o citoplasma e os vacúolos de armazenamento. A perspectiva na biossíntese deABI foi construída com os estudos de exemplares de importância farmacológica...

Taxus globosa S. cell lines: initiation, selection and characterization in terms of growth, and of baccatin III and paclitaxel production

Of the initial six cell lines originating from explants of Taxus globosa, or Mexican yew (stem internode, leaves and meristematic tissue), three were selected for their microbial and oxidation resistance, two from leaves and the other from stem internode. A study of their behavior, both in terms of cell growth, and of baccatin III and paclitaxel production, was developed in suspension cultures with an initially standardized biomass (fresh weight 0.23 g/L) using modified Gamborg's B5 medium, and an elicitor (methyl jasmonate), on either the first or seventh day of culture, at several levels (0, 0.1, 1, 10, 100 microM). In most of the conditions used, the three cell lines showed growth associated baccatin III production. The cell line from stem internode was the highest producer of baccatin III using 1 microM elicit or, sampling at 10 days.

[Review on new techniques in tropane alkaloids production]

Increasing from day to day tendency of human societies to plant based drug usage increased demand of secondary metabolite application. Although artificial production of these compounds greatly progressed, but the only way to achieve these fine medicinal compounds has been to extract them from plant resources. Alkaloid field, although very old, is still in its infancy with regard to being fully understood, and biotechnologically exploited. Up to now, approximately 5000 different alkaloids, in 15% of plants that belong to 150 families, have been recognized, that tropane alkaloids such as hyosyamine, scopolamine, atropine and cocaine, with a broad medical usage are a class of them. Industrial tropane alkaloid production by modern techniques such as cell and tissue culture, somatic hybridization, metabolic engineering and commercial large scale culture, is highly concerned nowadays and in this review, the authors have tried to point out some of the results obtained by application of these techniques

Enzymology of indole alkaloid biosynthesis in Catharanthus roseus.

Indole alkaloids in Catharanthus roseus have been in focus because of their medicinal value. These alkaloids consist of an indole moiety provided by tryptamine and a terpenoid portion provided by the secologanin. The most important catharanthus alkaloids are vinblastine (VLB), vincristine (VCR) and ajmalicine. VLB and VCR are clinically useful anticancer agents whereas ajmalicine is used for the treatment of circulatory diseases. VCR and VLB are the most expensive because of their low abundance in the plant, and are formed by the coupling of monomeric indole alkaloids vindoline and catharanthine, catalysed by peroxidases. The pathway that lead to monomeric indole alkaloids involves more than 20 enzymes of which 16 enzymes have been isolated and characterized biochemically, and only three at the molecular level. The present state of knowledge on enzymes and genes involved in indole alkaloid biosynthesis and various aspects of their regulation has been discussed.

Acción del hongo Helminthosporium sacharii en la acumulación de alcaloides en suspensiones celulares de Catharanthus roseus G Don / Helminthosporium sacharii fungus action in alkaloid accumulation in cell suspension of Catharanthus roseus G Don

Se ha demostrado que cuando se produce un estrés en las células vegetales, se estimula o induce la producción de metabolitos secundarios; para lograr estos fines se han empleado, fundamentalmente, agentes químicos y biológicos. En el presente trabajo se adicionó un homogeneizado del hongo Helminthosporium sacharii a una suspensión celular de Catharanthus roseus (L) G Don, para observar su efecto sobre la estimulación de la producción de alcaloides en dicha especie vegetal. Se realizaron diversas determinaciones químicas y biológicas en el momento de la inoculación del hongo, y a los 4, 8 y 12 días posteriores a su inoculación. Los resultados evidenciaron un ligero incremento de la producción de alcaloides por la suspensión de C. roseus inoculada, observándose que la tetrahidroalstonina fue el alcaloide mayormente producido en todos los tiempos de incubación