Your browser doesn't support javascript.
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 872
Filtrar
1.
Nat Chem Biol ; 16(4): 383-386, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32066966

RESUMO

Cycloaddition reactions generate chemical complexity in a single step. Here we report the crystal structures of three homologous plant-derived cyclases involved in the biosynthesis of iboga and aspidosperma alkaloids. These enzymes act on the same substrate, named angryline, to generate three distinct scaffolds. Mutational analysis reveals how these highly similar enzymes control regio- and stereo-selectivity.


Assuntos
Alcaloides/biossíntese , Aspidosperma/química , Tabernaemontana/química , Alcaloides/química , Carbazóis/química , Reação de Cicloadição/métodos , Alcaloides Indólicos/química , Plantas/química
2.
Plant Mol Biol ; 102(4-5): 477-499, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31902069

RESUMO

KEY MESSAGE: The study carry out comprehensive transcriptome analysis of C. deltoidea and exploration of BIAs biosynthesis and accumulation based on UHPLC-MS/MS and combined sequencing platforms. Coptis deltoidea is an important medicinal plant with a long history of medicinal use, which is rich in benzylisoquinoline alkaloids (BIAs). In this study, Ultra performance liquid chromatography-electrospray ionization tandem mass spectrometry (UHPLC-ESI-MS/MS) and combined sequencing platforms were performed for exploration of BIAs biosynthesis, accumulation and comprehensive transcriptome analysis of C. deltoidea. By metabolism profiling, the accumulation of ten BIAs was analyzed using UHPLC-MS/MS and different contents were observed in different organs. From transcriptome sequencing result, we applied single-molecule real-time (SMRT) sequencing to C. deltoidea and generated a total of 75,438 full-length transcripts. We proposed the candidate biosynthetic pathway of tyrosine, precursor of BIAs, and identified 64 full length-transcripts encoding enzymes putatively involved in BIAs biosynthesis. RNA-Seq data indicated that the majority of genes exhibited relatively high expression level in roots. Transport of BIAs was also important for their accumulation. Here, 9 ABC transporters and 2 MATE transporters highly homologous to known alkaloid transporters related with BIAs transport in roots and rhizomes were identified. These findings based on the combined sequencing platforms provide valuable genetic information for C. deltoidea and the results of transcriptome combined with metabolome analysis can help us better understand BIAs biosynthesis and transport in this medicinal plant. The information will be critical for further characterization of C. deltoidea transcriptome and molecular-assisted breeding for this medicinal plant with scarce resources.


Assuntos
Alcaloides/biossíntese , Benzilisoquinolinas/química , Coptis/genética , Coptis/metabolismo , Transcriptoma , Cromatografia Líquida de Alta Pressão , Perfilação da Expressão Gênica , Regulação da Expressão Gênica de Plantas , Filogenia , Folhas de Planta/metabolismo , Raízes de Plantas/metabolismo , Plantas Medicinais/metabolismo , Rizoma/metabolismo , Análise de Sequência de DNA , Espectrometria de Massas por Ionização por Electrospray , Espectrometria de Massas em Tandem
3.
Appl Biochem Biotechnol ; 190(1): 73-89, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31301009

RESUMO

Curvulamine, a novel scaffold alkaloid with remarkable selective antibacterial activity, is produced by marine fungus Curvularia sp. IFB-Z10. However, its deep pharmaceutical research and application are severely restricted by the low yield, which needs to be solved urgently. The purpose of this study was to improve curvulamine production via precursors co-addition strategy and further reveal the regulation mechanism. In this work, the optimal precursors co-addition conditions were firstly obtained, and curvulamine production achieved 166.74 mg/L with the supply of 250 mg/L alanine and 200 mg/L proline at 60 h, which was 4.08 times that of control. It was observed that under alanine and proline stimulation, fungus exhibited the morphology of a small-diameter compact pellet. Furthermore, the organic acid levels in central carbon metabolism (CCM) were declined with precursors supplement. Besides, precursors also induced the critical biosynthetic gene transcriptions. The above findings collectively promoted curvulamine synthesis. Finally, Curvularia sp. IFB-Z10 fermentation process was successfully established by feeding alanine and proline at 0.021 g/L/h and 0.017 g/L/h rate from 60 to 72 h, and curvulamine production reached 133.58 mg/L in a 5-L bioreactor. The information acquired would facilitate the enhancement of curvulamine yield in submerged fermentation and the research on synthesis regulation of other alkaloids.


Assuntos
Alcaloides/biossíntese , Ascomicetos/metabolismo , Aminoácidos/metabolismo , Ascomicetos/genética , Ascomicetos/crescimento & desenvolvimento , Reatores Biológicos , Metabolismo dos Carboidratos , Divisão Celular , Fermentação , Genes Fúngicos , Nitrogênio/metabolismo , Transcrição Genética
4.
Fitoterapia ; 140: 104412, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31698060

RESUMO

Aconitum carmichaelii has been used in traditional Chinese medicine for treating various diseases for several thousand years. Based on the biosynthetic pathway of some alkaloids such as C19-diterpenoid alkaloids and obvious differences in alkaloid content between leaves of two A. carmichaelii varieties has been reported, we performed leaves transcriptome analysis of two A. carmichaelii varieties. Besides we characterized the biosynthetic pathway of salsolinol. A total of 56 million raw reads (8.28 G) and 55 million clean reads (8.24 G) were obtained from two varieties (Z175 and R184) leaves transcriptome, respectively, and 176,793 unigenes were annotated. 281 and 843 unigenes are involved in the salsolinol biosynthetic pathway and the formation of C19-diterpenoid alkaloids respectively. And including 34 and 24 unigenes are the differentially expressed genes (DEGs) in the biosynthesis pathway for C19-diterpenoid alkaloids and salsolinol between Z175 and R184 respectively, which were target genes to explore differences in C19-diterpenoid alkaloid and salsolinol biosynthesis in Z175 and R184. Thus genes involved in alkaloid biosynthesis and accumulation differ between varieties leaves. The mechanisms underlying the differences and their relevance require further exploration. The results expand our knowledge of alkaloids biosynthesis in A. carmichaelii leaves, and provide a theoretical basis for analysis differences in alkaloids biosynthesis patterns in different varieties.


Assuntos
Aconitum/química , Vias Biossintéticas , Isoquinolinas/química , Transcriptoma , Alcaloides/biossíntese , China , Diterpenos/química , Perfilação da Expressão Gênica , Compostos Fitoquímicos/isolamento & purificação , Compostos Fitoquímicos/farmacologia , Folhas de Planta/química , Plantas Medicinais/química
5.
Plant Sci ; 290: 110293, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31779893

RESUMO

Class I TGA transcription factors (TFs) are known to participate in plant resistance responses, however, their regulatory functions in the biosynthesis of secondary metabolites were rarely revealed. In this study, a class I TGA TF, TwTGA1, from Tripterygium wilfordii Hook.f. was cloned and characterized. Overexpression of TwTGA1 in T. wilfordii Hook.f. cells increased the production of triptolide and two sesquiterpene pyridine alkaloids, which was further enhanced by methyl jasmonate (MeJA) treatment. RNA interference of TwTGA1 showed no significant effects on the production of these metabolites, indicating the existence of other TGA partner(s) with overlapping functions. Heterologous expression of TwTGA1 in tobacco By-2 cells promoted the biosynthesis of pyridine alkaloids. Under the elicitation of MeJA, the contents of nonpyrrolidine alkaloids further increased but not for nicotine. TwTGA1 could induce the expression of Putrescine N-methyltransferase (PMT) and N-methylputrescine oxidase 1 (MPO1) through binding to their promoters. Finally, transient expression of TwTGA1 in leaves of Catharanthus roseus changed both the profiles of vinca alkaloids (increased contents of serpentine and catharanthine, but decreased that of vinblastine) and the expressions of biosynthesis-related genes. The metabolic and transcriptional data indicated a relationship between jasmonic acid signaling pathway and the functions of TwTGA1.


Assuntos
Regulação da Expressão Gênica de Plantas , Proteínas de Plantas/genética , Fatores de Transcrição/genética , Tripterygium/genética , Alcaloides/biossíntese , Sequência de Aminoácidos , Catharanthus/metabolismo , Diterpenos/metabolismo , Compostos de Epóxi/metabolismo , Fenantrenos/metabolismo , Filogenia , Proteínas de Plantas/química , Proteínas de Plantas/metabolismo , Plantas Geneticamente Modificadas/metabolismo , Metabolismo Secundário , Alinhamento de Sequência , Fatores de Transcrição/química , Fatores de Transcrição/metabolismo , Tripterygium/metabolismo
6.
Proc Natl Acad Sci U S A ; 117(2): 1174-1180, 2020 01 14.
Artigo em Inglês | MEDLINE | ID: mdl-31882449

RESUMO

Indolizidine alkaloids such as anticancer drugs vinblastine and vincristine are exceptionally attractive due to their widespread occurrence, prominent bioactivity, complex structure, and sophisticated involvement in the chemical defense for the producing organisms. However, the versatility of the indolizidine alkaloid biosynthesis remains incompletely addressed since the knowledge about such biosynthetic machineries is only limited to several representatives. Herein, we describe the biosynthetic gene cluster (BGC) for the biosynthesis of curvulamine, a skeletally unprecedented antibacterial indolizidine alkaloid from Curvularia sp. IFB-Z10. The molecular architecture of curvulamine results from the functional collaboration of a highly reducing polyketide synthase (CuaA), a pyridoxal-5'-phosphate (PLP)-dependent aminotransferase (CuaB), an NADPH-dependent dehydrogenase (CuaC), and a FAD-dependent monooxygenase (CuaD), with its transportation and abundance regulated by a major facilitator superfamily permease (CuaE) and a Zn(II)Cys6 transcription factor (CuaF), respectively. In contrast to expectations, CuaB is bifunctional and capable of catalyzing the Claisen condensation to form a new C-C bond and the α-hydroxylation of the alanine moiety in exposure to dioxygen. Inspired and guided by the distinct function of CuaB, our genome mining effort discovers bipolamines A-I (bipolamine G is more antibacterial than curvulamine), which represent a collection of previously undescribed polyketide alkaloids from a silent BGC in Bipolaris maydis ATCC48331. The work provides insight into nature's arsenal for the indolizidine-coined skeletal formation and adds evidence in support of the functional versatility of PLP-dependent enzymes in fungi.


Assuntos
Alcaloides/biossíntese , Ascomicetos/enzimologia , Ascomicetos/metabolismo , Indolizidinas/metabolismo , Policetídeo Sintases/metabolismo , Fosfato de Piridoxal/metabolismo , Alcaloides/genética , Alcaloides/isolamento & purificação , Antibacterianos/metabolismo , Ascomicetos/genética , Aspergillus oryzae/genética , Aspergillus oryzae/metabolismo , Catálise , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Genes Fúngicos/genética , Hidroxilação , Proteínas de Membrana Transportadoras/genética , Proteínas de Membrana Transportadoras/metabolismo , Oxigenases de Função Mista/genética , Oxigenases de Função Mista/metabolismo , Família Multigênica , Filogenia , Policetídeo Sintases/classificação , Policetídeo Sintases/genética , Policetídeos , Fosfato de Piridoxal/genética , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Transaminases/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo
7.
BMC Plant Biol ; 19(1): 560, 2019 Dec 18.
Artigo em Inglês | MEDLINE | ID: mdl-31852435

RESUMO

BACKGROUND: Croton draco is an arboreal species and its latex as well as some other parts of the plant, are traditionally used in the treatment of a wide range of ailments and diseases. Alkaloids, such as magnoflorine, prevent early atherosclerosis progression while taspine, an abundant constituent of latex, has been described as a wound-healer and antitumor-agent. Despite the great interest for these and other secondary metabolites, no omics resources existed for the species and the biosynthetic pathways of these alkaloids remain largely unknown. RESULTS: To gain insights into the pathways involved in magnoflorine and taspine biosynthesis by C. draco and identify the key enzymes in these processes, we performed an integrated analysis of the transcriptome and metabolome in the major organs (roots, stem, leaves, inflorescences, and flowers) of this species. Transcript profiles were generated through high-throughput RNA-sequencing analysis while targeted and high resolution untargeted metabolomic profiling was also performed. The biosynthesis of these compounds appears to occur in the plant organs examined, but intermediaries may be translocated from the cells in which they are produced to other cells in which they accumulate. CONCLUSIONS: Our results provide a framework to better understand magnoflorine and taspine biosynthesis in C. draco. In addition, we demonstrate the potential of multi-omics approaches to identify candidate genes involved in the biosynthetic pathways of interest.


Assuntos
Alcaloides/biossíntese , Aporfinas/metabolismo , Croton/metabolismo , Metaboloma , Transcriptoma , Vias Biossintéticas
8.
Nat Commun ; 10(1): 4702, 2019 10 16.
Artigo em Inglês | MEDLINE | ID: mdl-31619678

RESUMO

Black pepper (Piper nigrum), dubbed the 'King of Spices' and 'Black Gold', is one of the most widely used spices. Here, we present its reference genome assembly by integrating PacBio, 10x Chromium, BioNano DLS optical mapping, and Hi-C mapping technologies. The 761.2 Mb sequences (45 scaffolds with an N50 of 29.8 Mb) are assembled into 26 pseudochromosomes. A phylogenomic analysis of representative plant genomes places magnoliids as sister to the monocots-eudicots clade and indicates that black pepper has diverged from the shared Laurales-Magnoliales lineage approximately 180 million years ago. Comparative genomic analyses reveal specific gene expansions in the glycosyltransferase, cytochrome P450, shikimate hydroxycinnamoyl transferase, lysine decarboxylase, and acyltransferase gene families. Comparative transcriptomic analyses disclose berry-specific upregulated expression in representative genes in each of these gene families. These data provide an evolutionary perspective and shed light on the metabolic processes relevant to the molecular basis of species-specific piperine biosynthesis.


Assuntos
Alcaloides/biossíntese , Genoma de Planta , Piper nigrum/genética , Aciltransferases/genética , Benzodioxóis , Carboxiliases/genética , Mapeamento Cromossômico , Cromossomos , Sistema Enzimático do Citocromo P-450/genética , Perfilação da Expressão Gênica , Genômica , Glicosiltransferases/genética , Filogenia , Piperidinas , Alcamidas Poli-Insaturadas
9.
Food Chem ; 301: 125285, 2019 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-31387039

RESUMO

A method was developed and validated for determination of tryptoquialanines A and C in orange samples on epicarp (exterior peel), mesocarp (white peel), and endocarp (fruit juice) based on QuEChERS extraction and LC-MS/MS analysis. The method showed an excellent linearity over a range of 5-400 µg kg-1, with r2 ≥ 0.998. The limits of detection (LOD) and quantification (LOQ) were 5 and 10 µg kg-1, respectively. Recoveries showed values between 57 and 101%, with RSD ≤ 12%. Analysis of infected oranges showed diffusion of the alkaloids between the orange layers after 4 days post infection in concentrations > LOQ. Mycotoxin diffusion to healthy oranges after direct contact with infected oranges for 48 h, showed alkaloid concentrations ≥10 µg kg-1 on epicarp layer. The developed method can be easily applied for quality control in routine analysis of orange fruit due to the high risk that these tremorgenic alkaloids represent to human health.


Assuntos
Alcaloides/análise , Cromatografia Líquida/métodos , Citrus sinensis/microbiologia , Frutas/microbiologia , Penicillium/metabolismo , Espectrometria de Massas em Tandem/métodos , Alcaloides/biossíntese , Citrus sinensis/química , Frutas/química , Limite de Detecção , Micotoxinas/análise
10.
Chemistry ; 25(49): 11574-11580, 2019 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-31407847

RESUMO

The so-called Securinega alkaloids constitute a class of tetracyclic biologically active specialised metabolites isolated principally from subtropical plants belonging to the Phyllanthaceae family. Following a strategy based on alternative hypotheses for their biosynthesis, an easy and time-efficient divergent synthesis enabled access to twelve of those alkaloids featuring (neo)(nor)securinane skeletons. Moreover, this work permitted to reassign the absolute configurations of (+)-virosine B and (-)-episecurinol A.


Assuntos
Alcaloides/biossíntese , Alcaloides/química , Euphorbiaceae/química , Euphorbiaceae/metabolismo , Mesilatos/química , Conformação Molecular , Estereoisomerismo
11.
Chem Commun (Camb) ; 55(58): 8390-8393, 2019 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-31257394

RESUMO

Diverse bioactive alkaloids with a tryptophan 2,5-diketopiperazine (DKP) core and an annulated structure forming a methylated pyrroloindoline-DKP assembly have been isolated from various microbial sources. However, little is known about their biosynthesis. In this study, a novel indole C3 methyltransferase from Streptomyces sp. HPH0547 was discovered and characterized. Structural elucidation of the products revealed that this enzyme catalyzed unique pyrroloindoline cyclization in tryptophan-containing cyclodipeptides. This is the first C3 methyltransferase reported to catalyze pyrroloindoline cyclization in cyclic dipeptides, which provides a feasible and simple method to access diverse alkaloids.


Assuntos
Alcaloides/biossíntese , Proteínas de Bactérias/metabolismo , Dipeptídeos/biossíntese , Metiltransferases/metabolismo , Peptídeos Cíclicos/biossíntese , Streptomyces/enzimologia , Ciclização , Dicetopiperazinas/metabolismo , Modelos Químicos , Especificidade por Substrato , Triptofano/química , Triptofano/metabolismo
12.
Gene ; 712: 143962, 2019 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-31288057

RESUMO

Veratrum nigrum is protected plant of Melanthiaceae family, able to synthetize unique steroidal alkaloids important for pharmacy. Transcriptomes from leaves, stems and rhizomes of in vitro maintained V. nigrum plants were sequenced and annotated for genes and markers discovery. Sequencing of samples derived from the different organs resulted in a total of 108,511 contigs with a mean length of 596 bp. Transcripts derived from leaf and stalk were annotated at 28%, and 38% in Nr nucleotide database, respectively. The sequencing revealed 949 unigenes related with lipid metabolism, including 73 transcripts involved in steroids and genus-specific steroid alkaloids biosynthesis. Additionally, 3203 candidate SSRs markers we identified in unigenes with average density of one SSR locus every 6.2 kb sequence. Unraveling of biochemical machinery of the pathway responsible for steroidal alkaloids will open possibility to design and optimize biotechnological process. The transcriptomic data provide valuable resources for biochemical, molecular genetics, comparative transcriptomics, functional genomics, ecological and evolutionary studies of V. nigrum.


Assuntos
Alcaloides/biossíntese , Regulação da Expressão Gênica de Plantas , Esteroides/biossíntese , Transcriptoma , Veratrum/metabolismo , Mapeamento de Sequências Contíguas , DNA Complementar/metabolismo , Biblioteca Gênica , Ontologia Genética , Marcadores Genéticos , Sequenciamento de Nucleotídeos em Larga Escala , Repetições de Microssatélites , Anotação de Sequência Molecular , Análise de Sequência com Séries de Oligonucleotídeos , Folhas de Planta/metabolismo , Proteínas de Plantas/metabolismo , Raízes de Plantas/metabolismo , Análise de Sequência de RNA
13.
Molecules ; 24(12)2019 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-31208056

RESUMO

The strain Streptomyces osmaniensis CA-244599 isolated from the Comoros islands was submitted to liquid-state fermentation coupled to in situ solid-phase extraction with amberlite XAD-16 resin. Elution of the trapped compounds on the resin beads by ethyl acetate afforded seven metabolites, osmanicin (1), streptazolin (2), streptazone C (3), streptazone B1 (4), streptenol C (5), nocardamine (6) and desmethylenylnocardamine (7). Osmanicin (1) is a newly reported unusual scaffold combining streptazolin (2) and streptazone C (3) through a Diels-Alder type reaction. Experimental evidence excluded the spontaneous formation of 1 from 2 and 3. The isolated compounds were evaluated for their ability to inhibit elastase using normal human diploid fibroblasts. Compound 1 exhibited the most potent activity with an IC50 of 3.7 µM.


Assuntos
Alcaloides/farmacologia , Fibroblastos/efeitos dos fármacos , Fibroblastos/metabolismo , Elastase Pancreática/antagonistas & inibidores , Policetídeos/farmacologia , Streptomyces/química , Alcaloides/biossíntese , Alcaloides/química , Alcaloides/isolamento & purificação , Vias Biossintéticas , Sobrevivência Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Fermentação , Humanos , Espectroscopia de Ressonância Magnética , Modelos Moleculares , Conformação Molecular , Estrutura Molecular , Policetídeos/química , Policetídeos/isolamento & purificação , Policetídeos/metabolismo , RNA Ribossômico 16S/genética , Streptomyces/classificação , Streptomyces/genética
14.
Appl Microbiol Biotechnol ; 103(14): 5867-5878, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31119352

RESUMO

Huperzine A (HupA) is a potent acetylcholinesterase (AChE) inhibitor of a great consideration as a prospective drug candidate for Alzheimer's disease treatment. Production of HupA by endophytes offers an alternative challenge to reduce the massive plant harvest needed to meet the increasing demand of HupA. In the current study, some endophytic fungal and actinobacterial isolates from the Chinese herb, Huperzia serrata, underwent liquid fermentation, alkaloid extraction, and screening for AChE inhibition and HupA production. Among these isolates, Alternaria brassicae AGF041 strain was the only positive strain for HupA production with the maximum AChE inhibition of 75.5%. Chromatographic analyses verified the identity of the produced HupA. The HupA production was efficiently maximized up to 42.89 µg/g of dry mycelia, after optimization of thirteen process parameters using multifactorial statistical approaches, Plackett-Burman and central composite designs. The statistical optimization resulted in a 40.8% increase in HupA production. This is the first report to isolate endophytic actinobacteria with anti-AChE activity from H. serrata, and to identify an endophytic fungus A. brassicae as a new promising start strain for a higher HupA yield.


Assuntos
Alcaloides/biossíntese , Alternaria/metabolismo , Inibidores da Colinesterase/metabolismo , Fermentação , Huperzia/microbiologia , Cromatografia Líquida de Alta Pressão , Cromatografia em Camada Delgada , Micélio , Estudos Prospectivos , Sesquiterpenos
15.
Mol Biotechnol ; 61(7): 498-505, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31119478

RESUMO

Taxoid 10ß-O-acetyltransferase (DBAT) is the key enzyme to produce baccatin III, a key precursor in paclitaxel synthesis, by acetyl group transfer from acetyl-CoA to the C10 hydroxyl of 10-deacetylbaccatin III. In this study, the recombinant DBAT (rDBAT) was immobilized by cross-linked enzyme aggregates (CLEAs). To further optimize the enzyme recovery, single-factor experiment and response surface methodology were applied. 60% ammonium sulfate as precipitant, 0.05% glutaraldehyde as fixing agent, pH 7.0, 2 h as cross-linking time, 30 °C as cross-linking temperature were confirmed to be the optimum conditions to prepare the CLEAs-rDBAT in single-factor experiment. In addition, 62% for ammonium sulfate saturation, 0.15% for glutaraldehyde, and pH 6.75 were confirmed to be the optimum conditions with averagely 73.9% activity recovery in 3 replications, which was consistent with the prediction of response surface methodology. After cross-linking, the optimum temperature of CLEAs-rDBAT rose up to 70 °C and CLEAs-rDBAT could be recycled for three times.


Assuntos
Acetiltransferases/biossíntese , Alcaloides/biossíntese , Enzimas Imobilizadas/biossíntese , Proteínas Recombinantes/biossíntese , Acetiltransferases/genética , Alcaloides/genética , Reagentes para Ligações Cruzadas , Paclitaxel/biossíntese , Taxoides
16.
Mar Drugs ; 17(4)2019 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-30934741

RESUMO

Vibrio diabolicus A1SM3 strain was isolated from a sediment sample from Manaure Solar Saltern in La Guajira and the produced crude extracts have shown antibacterial activity against methicillin-resistant Staphylococcus aureus and cytotoxic activity against human lung cell line. Thus, the aim of this research was to identify the main compound responsible for the biological activity observed and to systematically study how each carbon and nitrogen source in the growth media, and variation of the salinity, affect its production. For the characterization of the bioactive metabolites, 15 fractions obtained from Vibrio diabolicus A1SM3 crude extract were analyzed by HPLC-MS/MS and their activity was established. The bioactive fractions were dereplicated with Antibase and Marinlit databases, which combined with nuclear magnetic resonance (NMR) spectra and fragmentation by MS/MS, led to the identification of 2,2-di(3-indolyl)-3-indolone (isotrisindoline), an indole-derivative antibiotic, previously isolated from marine organisms. The influence of the variations of the culture media in isotrisindoline production was established by molecular network and MZmine showing that the media containing starch and peptone at 7% NaCl was the best culture media to produce it. Also, polyhydroxybutyrates (PHB) identification was established by MS/MS mainly in casamino acids media, contributing to the first report on PHB production by this strain.


Assuntos
Antibacterianos/biossíntese , Antibacterianos/farmacologia , Antineoplásicos/metabolismo , Antineoplásicos/farmacologia , Técnicas Bacteriológicas/métodos , Vibrio/química , Vibrio/metabolismo , Alcaloides/biossíntese , Alcaloides/isolamento & purificação , Alcaloides/farmacologia , Antibacterianos/isolamento & purificação , Antineoplásicos/isolamento & purificação , Organismos Aquáticos/microbiologia , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Misturas Complexas/química , Misturas Complexas/isolamento & purificação , Meios de Cultura , Humanos , Hidroxibutiratos/química , Hidroxibutiratos/farmacologia , Isoindóis/isolamento & purificação , Isoindóis/metabolismo , Modelos Moleculares , Poliésteres/química , Poliésteres/farmacologia , Poli-Hidroxialcanoatos/química , Poli-Hidroxialcanoatos/farmacologia , Salinidade
17.
Molecules ; 24(4)2019 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-30813289

RESUMO

Tropane alkaloids (TA) are valuable secondary plant metabolites which are mostly found in high concentrations in the Solanaceae and Erythroxylaceae families. The TAs, which are characterized by their unique bicyclic tropane ring system, can be divided into three major groups: hyoscyamine and scopolamine, cocaine and calystegines. Although all TAs have the same basic structure, they differ immensely in their biological, chemical and pharmacological properties. Scopolamine, also known as hyoscine, has the largest legitimate market as a pharmacological agent due to its treatment of nausea, vomiting, motion sickness, as well as smooth muscle spasms while cocaine is the 2nd most frequently consumed illicit drug globally. This review provides a comprehensive overview of TAs, highlighting their structural diversity, use in pharmaceutical therapy from both historical and modern perspectives, natural biosynthesis in planta and emerging production possibilities using tissue culture and microbial biosynthesis of these compounds.


Assuntos
Alcaloides/biossíntese , Alcaloides/farmacologia , Erythroxylaceae/química , Solanaceae/química , Alcaloides/química , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Humanos , Estrutura Molecular , Extratos Vegetais/biossíntese , Extratos Vegetais/farmacologia , Metabolismo Secundário , Tropanos/síntese química , Tropanos/química , Tropanos/farmacologia
18.
Alkaloids Chem Biol ; 82: 147-304, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30850031

RESUMO

This chapter presents an overview of the chemistry and pharmacology of the alkaloids found in species of the Lauraceae family. The occurrence of alkaloids from Lauraceae species as well as their chemical structures is summarized in informative and easy-to-understand tables. Within the Lauraceae family, the genera Ocotea (195), Litsea (180), Cryptocarya (133), and Neolitsea (110) have led to the greater number of publications regarding alkaloids content. Valuable and comprehensive information about the structure of these alkaloids is provided. The alkaloids of the aporphine type, found in 22 of the 23 genera, represent the predominant group in this family. Many of the isolated alkaloids exhibit unique structures. From plants of this family, 22 different types of skeletons have been isolated, among them only the purine alkaloids are classified as pseudoalkaloids, and the types phenethylamines, phenethylcinnamides, and phthalidoisoquinoline are classified as protoalkaloids. The chapter is presented as a contribution for the scientific community, mainly to enable the search for alkaloids in species belonging to the Lauraceae family.


Assuntos
Alcaloides/química , Lauraceae/química , Alcaloides/biossíntese , Lauraceae/metabolismo , Estrutura Molecular
20.
ACS Chem Biol ; 14(2): 176-181, 2019 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-30649848

RESUMO

Bacterial aminophenylpyrrole-derived alkaloids (APPAs) represent high value lead compounds. Pyrrolnitrin, which was developed into globally important fungicides, is the only reported APPA produced by Proteobacteria. Recently, various APPAs showing diverse bioactivities were discovered from Bacteroidetes. Here, a bioinformatics and phylogenetic approach enabled the elucidation of the biosynthesis of the highly diverse APPAs in Cytophagales bacteria and their chemical diversification strategy. The biosynthetic gene clusters were identified in producer strains, and the biosynthesis was experimentally validated by heterologous expression experiments in E. coli. First, one enzyme-dependent biosynthetic step yields the tryptophan-derived precursor 3-(2'-aminophenyl)-pyrrole. Second, a spontaneous Pictet-Spengler-like coupling reaction enables the bacterial producer strains to create a library of tricyclic alkaloids, since several aldehydes can be applied as substrates. The diversity of this natural products class is further enlarged by the catalytic action of a methyltransferase, which adds one or more methyl groups to the aminophenyl intermediate.


Assuntos
Alcaloides/biossíntese , Alcaloides/química , Pirróis/química , Bactérias/metabolismo , Estrutura Molecular
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA