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1.
IJU Case Rep ; 7(5): 351-354, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-39224683

RESUMEN

Introduction: Spontaneous bladder rupture is a potentially life-threatening condition. Its treatment often requires invasive strategies, mainly surgical closure, or cystectomy. We present a case where we successfully treated bladder rupture employing a less invasive technique of transurethral debridement and hyperbaric oxygen therapy. Case presentation: A woman in her 80s presenting with lower abdominal pain was suspected of vesicoenteric fistula. Subsequent investigations confirmed bladder rupture to the abdominal wall, which eventually developed into a vesicocutaneous fistula. To minimize the invasiveness of treatment, a combined strategy of transurethral debridement of the fistula, and hyperbaric oxygen therapy was taken, resulting in successful outcome. Conclusion: Our approach was unique for its tolerability in comparison to conventional surgical approaches taken towards this condition.

2.
J Nat Med ; 2024 Aug 22.
Artículo en Inglés | MEDLINE | ID: mdl-39174720

RESUMEN

Uncaria rhynchophylla (Miq.) Miq. (Rubiaceae) is widely used as a botanical raw material for traditional Japanese and Chinese medicines. However, not all of its potentially bioactive constituents have been isolated and characterized. Herein, one new indole alkaloid triglucoside (1), nine known alkaloids (2-10) and thirteen known non-alkaloids (11-23) were isolated from the aqueous extract of Uncaria rhynchophylla hook and structurally characterized 1H and 13C NMR and high-resolution electrospray ionization mass spectrometry. The absolute configurations of isolated compounds (1, 2 and 3) were determined by the X-ray diffraction analysis of their single crystals obtained using a micro-drop crystallization technique. This technique allows single crystals to be obtained from samples as small as 50 µg, thus providing detailed structural information even on minor constituents and enabling the accurate quality monitoring of botanical raw materials more accurately.

3.
J Clin Exp Hematop ; 64(3): 183-190, 2024 Sep 28.
Artículo en Inglés | MEDLINE | ID: mdl-39085130

RESUMEN

Kikuchi-Fujimoto disease (KFD), also known as histiocytic necrotizing lymphadenitis, is a rare condition characterized by benign localized lymphadenopathy and clinical symptoms such as fever, sore throat, odynophagia, and leukopenia. Though the etiology of KFD is unknown, this condition is similar to viral infection, including increased infiltration of activated plasmacytoid dendritic cells. KFD exhibits three histological phases that reflect its progression status: proliferative, necrotic, and xanthomatous lesions. The expression loss of pan T-cell markers, such as CD2, CD5, and CD7, of infiltrating T-cells is observed in KFD cases, complicating the distinction from T-cell lymphoma. However, reports on the loss of their expression in KFD have been limited. Furthermore, the precise population of the T-cell subset in KFD is still unclear. Here, we focused on surface markers and transcription factors for T-cell differentiation and analyzed them immunohistochemically in 46 KFD cases. We observed diminished CD5 expression of CD8-positive (CD5dim CD8+) T-cells in the proliferative lesion of KFD cases. Furthermore, these CD5dim CD8+ T-cells expressed T-BET, a master regulator of type 1 helper T-cells. The upregulation of T-BET and downregulation of CD5 in CD8+ T-cells causes dysregulated activation and proliferation of CD8+ T-cells, potentially contributing to the unique histopathological features of KFD. Recognizing the frequent infiltration of T-BET-positive CD5dim CD8+ T-cells in KFD is important for distinguishing it from mature T-cell lymphoma. Our findings suggest that the immune response in KFD shares similarities with viral infections and highlight the importance of characterizing T-BET-positive CD5dim CD8+ T-cell populations for understanding KFD pathogenesis.


Asunto(s)
Antígenos CD5 , Linfocitos T CD8-positivos , Linfadenitis Necrotizante Histiocítica , Proteínas de Dominio T Box , Linfadenitis Necrotizante Histiocítica/patología , Linfadenitis Necrotizante Histiocítica/diagnóstico , Linfadenitis Necrotizante Histiocítica/metabolismo , Humanos , Antígenos CD5/metabolismo , Linfocitos T CD8-positivos/inmunología , Linfocitos T CD8-positivos/patología , Linfocitos T CD8-positivos/metabolismo , Proteínas de Dominio T Box/metabolismo , Adulto , Masculino , Femenino , Persona de Mediana Edad , Anciano
4.
Hinyokika Kiyo ; 70(5): 117-122, 2024 May.
Artículo en Japonés | MEDLINE | ID: mdl-38966921

RESUMEN

A 62-year-old male presenting with gross hematuria and right renal mass was referred to our Urology Department. Computed tomography revealed a right renal mass, with multiple pulmonary lesions. He underwent right nephrectomy for highly suspected renal cell carcinoma with pulmonary metastases (cT3aN0M1). The pathological diagnosis was clear cell renal cell carcinoma, pT1b. Following surgery, he was treated with multiple regimens of chemotherapy, ranging from interferon alpha, multiple tyrosine kinase inhibitors such as sorafenib, axitinib, pazopanib and cabozantinib, everolimus, and nivolumab, all of which were discontinued after its induction, either due to adverse events or progressive disease. He was finally administered Sunitinib as the 8th line "last-ditch" treatment, which resulted in significant tumor shrinkage. No disease progression has been observed 25 months after initiating sunitinib administration.


Asunto(s)
Antineoplásicos , Carcinoma de Células Renales , Indoles , Neoplasias Renales , Pirroles , Sunitinib , Humanos , Sunitinib/uso terapéutico , Masculino , Neoplasias Renales/tratamiento farmacológico , Neoplasias Renales/patología , Neoplasias Renales/diagnóstico por imagen , Persona de Mediana Edad , Indoles/uso terapéutico , Pirroles/uso terapéutico , Carcinoma de Células Renales/tratamiento farmacológico , Carcinoma de Células Renales/secundario , Carcinoma de Células Renales/diagnóstico por imagen , Antineoplásicos/uso terapéutico , Neoplasias Pulmonares/tratamiento farmacológico , Neoplasias Pulmonares/secundario , Neoplasias Pulmonares/patología , Nefrectomía , Tomografía Computarizada por Rayos X
6.
Acta Virol ; 67(1): 13-23, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36950882

RESUMEN

High-throughput RNA sequencing (RNA-seq) analysis of samples from Mallotus japonicus, a traditional medicinal plant, yielded two novel RNA viruses tentatively named Mallotus japonicus virus A (MjVA) and Mallotus japonicus virus B (MjVB). The MjVA and MjVB genomes encode proteins showing amino acid sequence similarities to those of poleroviruses (the genus Polerovirus, the family Solemoviridae) and amalgaviruses (the genus Amalgavirus, the family Amalgaviridae), respectively. The MjVA genome contains seven highly overlapping open reading frames, which are translated to seven proteins through various translational mechanisms, including -1 programmed ribosomal frameshifting (PRF) at the slippery motif GGGAAAC, non-AUG translational initiation, and stop codon readthrough. The MjVB genome encodes two proteins; one of which is translated by +1 PRF mechanism at the slippery motif UUUCGN. The abundance analysis of virus-derived RNA fragments revealed that MjVA is highly concentrated in plant parts with well-developed phloem tissues as previously demonstrated in other poleroviruses, which are transmitted by phloem feeders, such as aphids. MjVB, an amalgavirus generally transmitted by seeds, is distributed in all samples at low concentrations. Thus, this study demonstrates the effectiveness and usefulness of RNA-seq analysis of plant samples for the identification of novel RNA viruses and analysis of their tissue distribution. Keywords: Polerovirus; Amalgavirus; Mallotus japonicus; RNA virus; viral genome; programmed ribosomal frameshifting.


Asunto(s)
Luteoviridae , Mallotus (Planta) , Virus ARN , Luteoviridae/genética , Mallotus (Planta)/genética , Filogenia , ARN Viral/genética , Secuenciación de Nucleótidos de Alto Rendimiento , Sistemas de Lectura Abierta , Genoma Viral , Enfermedades de las Plantas
7.
Plant Cell Physiol ; 64(1): 64-79, 2023 Feb 16.
Artículo en Inglés | MEDLINE | ID: mdl-36218384

RESUMEN

White Kwao Krua (Pueraria candollei var. mirifica), a Thai medicinal plant, is a rich source of phytoestrogens, especially isoflavonoids and chromenes. These phytoestrogens are well known; however, their biosynthetic genes remain largely uncharacterized. Cytochrome P450 (P450) is a large protein family that plays a crucial role in the biosynthesis of various compounds in plants, including phytoestrogens. Thus, we focused on P450s involved in the isoflavone hydroxylation that potentially participates in the biosynthesis of miroestrol. Three candidate P450s were isolated from the transcriptome libraries by considering the phylogenetic and expression data of each tissue of P. mirifica. The candidate P450s were functionally characterized both in vitro and in planta. Accordingly, the yeast microsome harboring PmCYP81E63 regiospecifically exhibited either 2' or 3' daidzein hydroxylation and genistein hydroxylation. Based on in silico calculation, PmCYP81E63 had higher binding energy with daidzein than with genistein, which supported the in vitro result of the isoflavone specificity. To confirm in planta function, the candidate P450s were then transiently co-expressed with isoflavone-related genes in Nicotiana benthamiana. Despite no daidzein in the infiltrated N. benthamiana leaves, genistein and hydroxygenistein biosynthesis were detectable by liquid Chromatography with tandem mass spectrometry (LC-MS/MS). Additionally, we demonstrated that PmCYP81E63 interacted with several enzymes related to isoflavone biosynthesis using bimolecular fluorescence complementation studies and a yeast two-hybrid analysis, suggesting a scheme of metabolon formation in the pathway. Our findings provide compelling evidence regarding the involvement of PmCYP81E63 in the early step of the proposed miroestrol biosynthesis in P. mirifica.


Asunto(s)
Isoflavonas , Pueraria , Fitoestrógenos , Pueraria/química , Pueraria/genética , Pueraria/metabolismo , Cromatografía Liquida , Hidroxilación , Genisteína , Filogenia , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Espectrometría de Masas en Tándem , Isoflavonas/metabolismo , Sistema Enzimático del Citocromo P-450/genética , Sistema Enzimático del Citocromo P-450/metabolismo
8.
DNA Res ; 29(6)2022 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-36535891

RESUMEN

A high-quality genome assembly is imperative to explore the evolutionary basis of characteristic attributes that define chemotype and provide essential resources for a molecular breeding strategy for enhanced production of medicinal metabolites. Here, using single-molecule high-fidelity (HiFi) sequencing reads, we report chromosome-scale genome assembly for Chinese licorice (Glycyrrhiza uralensis), a widely used herbal and natural medicine. The entire genome assembly was achieved in eight chromosomes, with contig and scaffold N50 as 36.02 and 60.2 Mb, respectively. With only 17 assembly gaps and half of the chromosomes having no or one assembly gap, the presented genome assembly is among the best plant genomes to date. Our results showed an advantage of using highly accurate long-read HiFi sequencing data for assembling a highly heterozygous genome including its complexed repeat content. Additionally, our analysis revealed that G. uralensis experienced a recent whole-genome duplication at approximately 59.02 million years ago post a gamma (γ) whole-genome triplication event, which contributed to its present chemotype features. The metabolic gene cluster analysis identified 355 gene clusters, which included the entire biosynthesis pathway of glycyrrhizin. The genome assembly and its annotations provide an essential resource for licorice improvement through molecular breeding and the discovery of valuable genes for engineering bioactive components and understanding the evolution of specialized metabolites biosynthesis.


Asunto(s)
Glycyrrhiza uralensis , Glycyrrhiza uralensis/genética , Glycyrrhiza uralensis/metabolismo , Cromosomas , Genoma de Planta , Vías Biosintéticas , Familia de Multigenes
9.
Plant Biotechnol (Tokyo) ; 39(3): 281-289, 2022 Sep 25.
Artículo en Inglés | MEDLINE | ID: mdl-36349240

RESUMEN

Marasmin [S-(methylthiomethyl)-L-cysteine-4-oxide] is a pharmaceutically valuable sulfur-containing compound produced by the traditional medicinal plant, Tulbaghia violacea. Here, we report the identification of an S-oxygenase, TvMAS1, that produces marasmin from its corresponding sulfide, S-(methylthiomethyl)-L-cysteine. The amino acid sequence of TvMAS1 showed high sequence similarity to known flavin-containing S-oxygenating monooxygenases in plants. Recombinant TvMAS1 catalyzed regiospecific S-oxygenation at S4 of S-(methylthiomethyl)-L-cysteine to yield marasmin, with an apparent K m value of 0.55 mM. TvMAS1 mRNA accumulated with S-(methylthiomethyl)-L-cysteine and marasmin in various organs of T. violacea. Our findings suggest that TvMAS1 catalyzes the S-oxygenation reaction during the last step of marasmin biosynthesis in T. violacea.

10.
J Nat Med ; 76(4): 803-810, 2022 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-35691991

RESUMEN

S-Alk(en)ylcysteine sulfoxides (CSOs), such as methiin, alliin, and isoalliin, are health-beneficial natural products biosynthesized in the genus Allium. Here, we report the induction of multiple callus tissue lines from three Allium vegetables, onion (A. cepa), Welsh onion (A. fistulosum), and Chinese chive (A. tuberosum), and their ability to accumulate CSOs. Callus tissues were initiated and maintained in the presence of picloram and 2-isopentenyladenine as auxin and cytokinin, respectively. For all plant species tested, the callus tissues almost exclusively accumulated methiin as CSO, while the intact plants contained a substantial amount of isoalliin together with methiin. These results suggest that the cellular developmental conditions and the regulatory mechanisms required for the biosynthesis of methiin are different from those of alliin and isoalliin. The methiin content in the callus tissues of onion and Welsh onion was much higher compared to that in the intact plants, and its cellular concentration could be estimated as 1.9-21.7 mM. The activity of alliinase that degrades CSOs in the callus tissues was much lower than that of the intact plants for onion and Welsh onion, but at similar levels as in the intact plants for Chinese chive. Our findings that the callus tissues of onion and Welsh onion showed high methiin content and low alliinase activity highlighted their potential as a plant-based system for methiin production.


Asunto(s)
Allium , Productos Biológicos , Cebollas/metabolismo , Sulfóxidos
11.
Bioorg Med Chem Lett ; 59: 128554, 2022 03 01.
Artículo en Inglés | MEDLINE | ID: mdl-35051575

RESUMEN

Motilin is a 22-amino-acid gastrointestinal (GI) hormone and is involved in the regulation of GI motility through binding to GPR38, the motilin receptor which is expressed on smooth muscle cells in the GI tract. Therefore, GPR38 agonists are expected to be novel gastrointestinal prokinetic agents for the treatment of functional gastrointestinal disorders such as gastroparesis and chronic constipation. We identified a series of N-methylanilide derivatives as novel non-macrolide GPR38 agonists. Among them, 12 di-l-tartrate (DS-3801b) was selected as a clinical candidate for further evaluation.


Asunto(s)
Compuestos de Anilina/farmacología , Ciclohexanos/farmacología , Descubrimiento de Drogas , Fármacos Gastrointestinales/farmacología , Gastroparesia/tratamiento farmacológico , Piperazinas/farmacología , Receptores Acoplados a Proteínas G/agonistas , Compuestos de Anilina/química , Animales , Ciclohexanos/síntesis química , Ciclohexanos/química , Relación Dosis-Respuesta a Droga , Fármacos Gastrointestinales/síntesis química , Fármacos Gastrointestinales/química , Gastroparesia/metabolismo , Humanos , Estructura Molecular , Piperazinas/síntesis química , Piperazinas/química , Conejos , Receptores Acoplados a Proteínas G/metabolismo , Relación Estructura-Actividad
12.
Int J Mol Sci ; 22(16)2021 Aug 17.
Artículo en Inglés | MEDLINE | ID: mdl-34445541

RESUMEN

Mallotus japonicus is a valuable traditional medicinal plant in East Asia for applications as a gastrointestinal drug. However, the molecular components involved in the biosynthesis of bioactive metabolites have not yet been explored, primarily due to a lack of omics resources. In this study, we established metabolome and transcriptome resources for M. japonicus to capture the diverse metabolite constituents and active transcripts involved in its biosynthesis and regulation. A combination of untargeted metabolite profiling with data-dependent metabolite fragmentation and metabolite annotation through manual curation and feature-based molecular networking established an overall metabospace of M. japonicus represented by 2129 metabolite features. M. japonicus de novo transcriptome assembly showed 96.9% transcriptome completeness, representing 226,250 active transcripts across seven tissues. We identified specialized metabolites biosynthesis in a tissue-specific manner, with a strong correlation between transcripts expression and metabolite accumulations in M. japonicus. The correlation- and network-based integration of metabolome and transcriptome datasets identified candidate genes involved in the biosynthesis of key specialized metabolites of M. japonicus. We further used phylogenetic analysis to identify 13 C-glycosyltransferases and 11 methyltransferases coding candidate genes involved in the biosynthesis of medicinally important bergenin. This study provides comprehensive, high-quality multi-omics resources to further investigate biological properties of specialized metabolites biosynthesis in M. japonicus.


Asunto(s)
Regulación de la Expresión Génica de las Plantas , Redes Reguladoras de Genes , Mallotus (Planta)/metabolismo , Metaboloma , Proteínas de Plantas/metabolismo , Transcriptoma , Perfilación de la Expresión Génica , Mallotus (Planta)/genética , Mallotus (Planta)/crecimiento & desarrollo , Especificidad de Órganos , Filogenia , Hojas de la Planta/genética , Hojas de la Planta/crecimiento & desarrollo , Hojas de la Planta/metabolismo , Proteínas de Plantas/genética , Raíces de Plantas/genética , Raíces de Plantas/crecimiento & desarrollo , Raíces de Plantas/metabolismo
13.
Nat Commun ; 12(1): 405, 2021 01 15.
Artículo en Inglés | MEDLINE | ID: mdl-33452249

RESUMEN

Plant genomes remain highly fragmented and are often characterized by hundreds to thousands of assembly gaps. Here, we report chromosome-level reference and phased genome assembly of Ophiorrhiza pumila, a camptothecin-producing medicinal plant, through an ordered multi-scaffolding and experimental validation approach. With 21 assembly gaps and a contig N50 of 18.49 Mb, Ophiorrhiza genome is one of the most complete plant genomes assembled to date. We also report 273 nitrogen-containing metabolites, including diverse monoterpene indole alkaloids (MIAs). A comparative genomics approach identifies strictosidine biogenesis as the origin of MIA evolution. The emergence of strictosidine biosynthesis-catalyzing enzymes precede downstream enzymes' evolution post γ whole-genome triplication, which occurred approximately 110 Mya in O. pumila, and before the whole-genome duplication in Camptotheca acuminata identified here. Combining comparative genome analysis, multi-omics analysis, and metabolic gene-cluster analysis, we propose a working model for MIA evolution, and a pangenome for MIA biosynthesis, which will help in establishing a sustainable supply of camptothecin.


Asunto(s)
Camptotecina/biosíntesis , Evolución Molecular , Genoma de Planta/genética , Proteínas de Plantas/genética , Rubiaceae/metabolismo , Vías Biosintéticas/genética , Cromosomas de las Plantas/genética , Mapeo Contig , Genómica , Proteínas de Plantas/metabolismo , Raíces de Plantas/metabolismo , Plantas Medicinales/genética , Plantas Medicinales/metabolismo , Rubiaceae/genética , Alcaloides de la Vinca/biosíntesis
14.
Chem Pharm Bull (Tokyo) ; 68(5): 487-490, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32378547

RESUMEN

Preasperterpenoid A, featuring a 5/7/(3)6/5 pentacyclic structure, is a C25 sesterterpenoid produced by Penicillium verruculosum. The results of density functional calculations on putative biosynthetic carbocation cyclization/rearrangements leading to preasperterpenoid A revealed a highly concerted four-step cyclization mechanism. Interestingly, two secondary carbocation structures were obtained as minima, but appeared almost as shoulders in the energy profile, and may represent essentially transient structures during the highly concerted reaction.


Asunto(s)
Teoría Funcional de la Densidad , Talaromyces/química , Conformación Molecular , Estereoisomerismo , Talaromyces/metabolismo
15.
DNA Res ; 27(2)2020 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-32426807

RESUMEN

Cornus officinalis, an important traditional medicinal plant, is used as major constituents of tonics, analgesics, and diuretics. While several studies have focused on its characteristic bioactive compounds, little is known on their biosynthesis. In this study, we performed LC-QTOF-MS-based metabolome and RNA-seq-based transcriptome profiling for seven tissues of C. officinalis. Untargeted metabolome analysis assigned chemical identities to 1,215 metabolites and showed tissue-specific accumulation for specialized metabolites with medicinal properties. De novo transcriptome assembly established for C. officinalis showed 96% of transcriptome completeness. Co-expression analysis identified candidate genes involved in the biosynthesis of iridoids, triterpenoids, and gallotannins, the major group of bioactive metabolites identified in C. officinalis. Integrative omics analysis identified 45 cytochrome P450s genes correlated with iridoids accumulation in C. officinalis. Network-based integration of genes assigned to iridoids biosynthesis pathways with these candidate CYPs further identified seven promising CYPs associated with iridoids' metabolism. This study provides a valuable resource for further investigation of specialized metabolites' biosynthesis in C. officinalis.


Asunto(s)
Cornus/genética , Metaboloma , Transcriptoma , Cornus/metabolismo , Sistema Enzimático del Citocromo P-450/genética , Sistema Enzimático del Citocromo P-450/metabolismo , Genómica/métodos , Taninos Hidrolizables/metabolismo , Iridoides/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Triterpenos/metabolismo
16.
BMC Plant Biol ; 19(1): 581, 2019 Dec 26.
Artículo en Inglés | MEDLINE | ID: mdl-31878891

RESUMEN

BACKGROUND: Pueraria candollei var. mirifica, a Thai medicinal plant used traditionally as a rejuvenating herb, is known as a rich source of phytoestrogens, including isoflavonoids and the highly estrogenic miroestrol and deoxymiroestrol. Although these active constituents in P. candollei var. mirifica have been known for some time, actual knowledge regarding their biosynthetic genes remains unknown. RESULTS: Miroestrol biosynthesis was reconsidered and the most plausible mechanism starting from the isoflavonoid daidzein was proposed. A de novo transcriptome analysis was conducted using combined P. candollei var. mirifica tissues of young leaves, mature leaves, tuberous cortices, and cortex-excised tubers. A total of 166,923 contigs was assembled for functional annotation using protein databases and as a library for identification of genes that are potentially involved in the biosynthesis of isoflavonoids and miroestrol. Twenty-one differentially expressed genes from four separate libraries were identified as candidates involved in these biosynthetic pathways, and their respective expressions were validated by quantitative real-time reverse transcription polymerase chain reaction. Notably, isoflavonoid and miroestrol profiling generated by LC-MS/MS was positively correlated with expression levels of isoflavonoid biosynthetic genes across the four types of tissues. Moreover, we identified R2R3 MYB transcription factors that may be involved in the regulation of isoflavonoid biosynthesis in P. candollei var. mirifica. To confirm the function of a key-isoflavone biosynthetic gene, P. candollei var. mirifica isoflavone synthase identified in our library was transiently co-expressed with an Arabidopsis MYB12 transcription factor (AtMYB12) in Nicotiana benthamiana leaves. Remarkably, the combined expression of these proteins led to the production of the isoflavone genistein. CONCLUSIONS: Our results provide compelling evidence regarding the integration of transcriptome and metabolome as a powerful tool for identifying biosynthetic genes and transcription factors possibly involved in the isoflavonoid and miroestrol biosyntheses in P. candollei var. mirifica.


Asunto(s)
Isoflavonas/biosíntesis , Pueraria/genética , Esteroides/biosíntesis , Transcriptoma , Perfilación de la Expresión Génica , Estudios de Asociación Genética , Secuenciación de Nucleótidos de Alto Rendimiento , Isoflavonas/genética , Fitoestrógenos/metabolismo , Pueraria/metabolismo
17.
Plant J ; 100(3): 505-521, 2019 11.
Artículo en Inglés | MEDLINE | ID: mdl-31364191

RESUMEN

Lysine decarboxylase converts l-lysine to cadaverine as a branching point for the biosynthesis of plant Lys-derived alkaloids. Although cadaverine contributes towards the biosynthesis of Lys-derived alkaloids, its catabolism, including metabolic intermediates and the enzymes involved, is not known. Here, we generated transgenic Arabidopsis lines by expressing an exogenous lysine/ornithine decarboxylase gene from Lupinus angustifolius (La-L/ODC) and identified cadaverine-derived metabolites as the products of the emerged biosynthetic pathway. Through untargeted metabolic profiling, we observed the upregulation of polyamine metabolism, phenylpropanoid biosynthesis and the biosynthesis of several Lys-derived alkaloids in the transgenic lines. Moreover, we found several cadaverine-derived metabolites specifically detected in the transgenic lines compared with the non-transformed control. Among these, three specific metabolites were identified and confirmed as 5-aminopentanal, 5-aminopentanoate and δ-valerolactam. Cadaverine catabolism in a representative transgenic line (DC29) was traced by feeding stable isotope-labeled [α-15 N]- or [ε-15 N]-l-lysine. Our results show similar 15 N incorporation ratios from both isotopomers for the specific metabolite features identified, indicating that these metabolites were synthesized via the symmetric structure of cadaverine. We propose biosynthetic pathways for the metabolites on the basis of metabolite chemistry and enzymes known or identified through catalyzing specific biochemical reactions in this study. Our study shows that this pool of enzymes with promiscuous activities is the driving force for metabolite diversification in plants. Thus, this study not only provides valuable information for understanding the catabolic mechanism of cadaverine but also demonstrates that cadaverine accumulation is one of the factors to expand plant chemodiversity, which may lead to the emergence of Lys-derived alkaloid biosynthesis.


Asunto(s)
Arabidopsis/metabolismo , Cadaverina/metabolismo , Carboxiliasas/metabolismo , Lupinus/enzimología , Metaboloma , Nitrógeno/metabolismo , Alcaloides/metabolismo , Arabidopsis/genética , Vías Biosintéticas , Carboxiliasas/genética , Expresión Génica , Lupinus/genética , Lisina/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Plantas Modificadas Genéticamente , Transgenes
18.
New Phytol ; 224(2): 848-859, 2019 10.
Artículo en Inglés | MEDLINE | ID: mdl-31436868

RESUMEN

Catharanthus roseus is a medicinal plant well known for producing bioactive compounds such as vinblastine and vincristine, which are classified as terpenoid indole alkaloids (TIAs). Although the leaves of this plant are the main source of these antitumour drugs, much remains unknown on how TIAs are biosynthesised from a central precursor, strictosidine, to various TIAs in planta. Here, we have succeeded in showing, for the first time in leaf tissue of C. roseus, cell-specific TIAs localisation and accumulation with 10 µm spatial resolution Imaging mass spectrometry (Imaging MS) and live single-cell mass spectrometry (single-cell MS). These metabolomic studies revealed that most TIA precursors (iridoids) are localised in the epidermal cells, but major TIAs including serpentine and vindoline are localised instead in idioblast cells. Interestingly, the central TIA intermediate strictosidine also accumulates in both epidermal and idioblast cells of C. roseus. Moreover, we also found that vindoline accumulation increases in laticifer cells as the leaf expands. These discoveries highlight the complexity of intercellular localisation in plant specialised metabolism.


Asunto(s)
Catharanthus/citología , Catharanthus/metabolismo , Metabolómica , Hojas de la Planta/citología , Alcaloides de Triptamina Secologanina/metabolismo , Técnicas de Cultivo de Célula , Análisis de Componente Principal
19.
Beilstein J Org Chem ; 15: 1890-1897, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31467610

RESUMEN

We previously showed that the regio- and stereoselectivity in terpene-forming reactions are determined by the conformations of the carbocation intermediates, which reflect the initial conformation of the substrate, geranylfarnesyl diphosphate (GFPP). However, it remains unclear how the initial conformation of GFPP is controlled, and which part(s) of the GFPP molecule are important for its fixation inside the substrate-binding pocket. Here, we present the first detailed analysis of the inherent atomic mobility in carbocation intermediates during sesterterpene biosynthesis. We identified two methyl groups as the least mobile of all the carbons of the carbocation intermediates in the first half of the cyclization cascade. Our analysis suggests that these two methyl groups are critical for the preorganization of GFPP in the biosynthetic pathways leading to sesterfisherol and quiannulatene.

20.
Front Plant Sci ; 10: 802, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31293608

RESUMEN

This review describes the application of computational chemistry to plant secondary metabolism, focusing on the biosynthetic mechanisms of terpene/terpenoid, alkaloid, flavonoid, and lignin as representative examples. Through these biosynthetic studies, we exhibit several computational methods, including density functional theory (DFT) calculations, theozyme calculation, docking simulation, molecular dynamics (MD) simulation, and quantum mechanics/molecular mechanics (QM/MM) calculation. This review demonstrates how modern computational chemistry can be employed as an effective tool for revealing biosynthetic mechanisms and the potential of computational chemistry-for example, elucidating how enzymes regulate regio- and stereoselectivity, finding the key catalytic residue of an enzyme, and assessing the viability of hypothetical pathways. Furthermore, insights for the next research objective involving application of computational chemistry to plant secondary metabolism are provided herein. This review will be helpful for plant scientists who are not well versed with computational chemistry.

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