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1.
Mol Microbiol ; 122(1): 68-80, 2024 07.
Artigo em Inglês | MEDLINE | ID: mdl-38845079

RESUMO

Iron is an essential element for microbial survival and secondary metabolism. However, excess iron availability and overloaded secondary metabolites can hinder microbial growth and survival. Microorganisms must tightly control iron homeostasis and secondary metabolism. Our previous studies have found that the stringent starvation protein A (SspA) positively regulates prodiginine biosynthesis by activating iron uptake in Pseudoalteromonas sp. strain R3. It is believed that the interaction between SspA and the small nucleotide ppGpp is important for iron to exert regulation functions. However, the roles of ppGpp in iron absorption and prodiginine biosynthesis, and the underlying relationship between ppGpp and SspA in strain R3 remain unclear. In this study, we found that ppGpp accumulation in strain R3 could be induced by limiting iron. In addition, ppGpp not only positively regulated iron uptake and prodiginine biosynthesis via increasing the SspA level but also directly repressed iron uptake and prodiginine biosynthesis independent of SspA, highlighting the finding that ppGpp can stabilize both iron levels and prodiginine production. Notably, the abolishment of ppGpp significantly increased prodiginine production, thus providing a theoretical basis for manipulating prodiginine production in the future. This dynamic ppGpp-mediated interaction between iron uptake and prodiginine biosynthesis has significant implications for understanding the roles of nutrient uptake and secondary metabolism for the survival of bacteria in unfavorable environments.


Assuntos
Proteínas de Bactérias , Regulação Bacteriana da Expressão Gênica , Ferro , Prodigiosina , Pseudoalteromonas , Pseudoalteromonas/metabolismo , Pseudoalteromonas/genética , Ferro/metabolismo , Prodigiosina/metabolismo , Prodigiosina/biossíntese , Prodigiosina/análogos & derivados , Proteínas de Bactérias/metabolismo , Proteínas de Bactérias/genética , Homeostase , Metabolismo Secundário
2.
Eur J Pharmacol ; 974: 176608, 2024 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-38663542

RESUMO

Prodiginines have been studied extensively for their anticancer activity, however, the majority of the research has focused on prodigiosin. In this study, cycloheptylprodigiosin (S-1) is extracted from marine bacterium Spartinivicinus ruber MCCC 1K03745T, and its anticancer property was investigated. It exhibits remarkable cytotoxicity against a panel of human lung cancer cell lines, with the IC50 values ranging from 84.89 nM to 661.2 nM. After 6 h of treatment, S-1 gradually accumulates on mitochondria and lysosomes. While lower doses of S-1 induce cell cycle arrest, treatment with higher doses results in cell death in apoptotic independent manner in both NCI-H1299 and NCI-H460 cell lines. Interestingly, treatment with S-1 leads to the accumulation of LC3B-II via pathways that vary among different cell lines. In addition to its role as an autophagy inhibitor, S-1 also promotes autophagy initiation as demonstrated by the increment of EGFP fragment in the EGFP-LC3 degradation assay, however, inhibition of autophagy does not rescue cells from death induced by S-1. Mechanistically, S-1 impairs autophagic flux through disrupting acidic lysosomal pH and blocking the maturation of cathepsin D. Moreover, treatment with S-1 enhanced secretion of both pro- and mature forms of cathepsin D, coincident with disintegration of trans-Golgi network. Interestingly, S-1 does not induce ferroptosis, pyroptosis or necroptosis in NCI-H1299 cells. However, treatment of NCI-H460 cells with S-1 induces methuosis, which can be suppressed by Rac1 inhibitor EHT 1864. Our data demonstrate that S-1 is an effective anticancer agent with potential therapeutic application.


Assuntos
Antineoplásicos , Carcinoma Pulmonar de Células não Pequenas , Catepsina D , Complexo de Golgi , Neoplasias Pulmonares , Prodigiosina , Humanos , Linhagem Celular Tumoral , Prodigiosina/farmacologia , Prodigiosina/análogos & derivados , Catepsina D/metabolismo , Carcinoma Pulmonar de Células não Pequenas/patologia , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Carcinoma Pulmonar de Células não Pequenas/metabolismo , Antineoplásicos/farmacologia , Complexo de Golgi/efeitos dos fármacos , Complexo de Golgi/metabolismo , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/patologia , Neoplasias Pulmonares/metabolismo , Autofagia/efeitos dos fármacos , Apoptose/efeitos dos fármacos , Lisossomos/efeitos dos fármacos , Lisossomos/metabolismo , Morte Celular/efeitos dos fármacos , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo
3.
Mol Biol Rep ; 48(8): 5965-5975, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34331180

RESUMO

BACKGROUND: Prodiginines are bacterial red polypyrrole pigments and multifaceted secondary metabolites. These agents have anti-proliferative, immunosuppressive, antimicrobial, and anticancer effects. Recent analysis revealed that prodigiosin hypersensitizes Serratia marcescens to gamma radiation. In the present study, we report the cytotoxicity and genotoxicity properties of undecylprodigiosin and butylcycloheptylprodigiosin in the presence and absence of radiation through the MTT and alkaline comet experiments. METHODS AND RESULTS: Findings demonstrated that undecylprodigiosin was at least a fivefold more cytotoxic at low radiation doses (1 and 3 Gy) on both MCF7 and HDF lines rather than in the absence or high radiation doses (5 Gy) (P value < 0.05). Although butylcycloheptylprodigiosin toxicity on MCF7 and HDF was dose-dependent, it was not influenced by any radiation doses (P value > 0.05). Comet findings confirmed that these compounds' genotoxicity is only dose-dependent. Radiation had no significant effects on DNA damage on any of the cells (P value > 0.05). CONCLUSIONS: In general, it can be concluded that the prodiginines are cytotoxic agents that act as a double-edged sword, radiosensitizers and radio-protective, respectively at low and high radiation doses in cancer treatment process. As the results they could be used in antitumor therapies very soon.


Assuntos
Neoplasias/terapia , Prodigiosina/análogos & derivados , Anti-Infecciosos , Antineoplásicos , Linhagem Celular , Dano ao DNA , Humanos , Imunossupressores , Células MCF-7 , Fármacos Fotossensibilizantes/farmacologia , Prodigiosina/metabolismo , Prodigiosina/farmacologia
4.
J Med Chem ; 64(12): 8739-8754, 2021 06 24.
Artigo em Inglês | MEDLINE | ID: mdl-34111350

RESUMO

Highly efficient and straightforward synthetic routes toward the first total synthesis of 2-(p-hydroxybenzyl)-prodigiosins (2-5), isoheptylprodigiosin (6), and geometric isomers of tambjamine MYP1 ((E/Z)-7) have been developed. The crucial steps involved in these synthetic routes are the construction of methoxy-bipyrrole-carboxaldehydes (MBCs) and a 20-membered macrocyclic core and a regioselective demethylation of MBC analogues. These new synthetic routes enabled us to generate several natural prodiginines 24-27 in larger quantity. All of the synthesized natural products exhibited potent asexual blood-stage antiplasmodial activity at low nanomolar concentrations against a panel of Plasmodium falciparum parasites, with a great therapeutic index. Notably, prodiginines 6 and 24-27 provided curative in vivo efficacy against erythrocytic Plasmodium yoelii at 25 mg/kg × 4 days via oral route in a murine model. No overt clinical toxicity or behavioral change was observed in any mice treated with prodiginines and tambjamines.


Assuntos
Antimaláricos/uso terapêutico , Prodigiosina/análogos & derivados , Prodigiosina/uso terapêutico , Pirróis/uso terapêutico , Animais , Antimaláricos/síntese química , Antimaláricos/toxicidade , Feminino , Células Hep G2 , Humanos , Camundongos , Estrutura Molecular , Testes de Sensibilidade Parasitária , Plasmodium falciparum/efeitos dos fármacos , Plasmodium yoelii/efeitos dos fármacos , Prodigiosina/toxicidade , Pirróis/síntese química , Pirróis/toxicidade , Estereoisomerismo , Relação Estrutura-Atividade
5.
J Appl Genet ; 62(1): 165-182, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33415709

RESUMO

Genetic manipulation of the undecylprodigiosin-producing strains and engineered culture medium approaches were applied as the most economical induction strategy for improving production. The hyper-producing recombinant strain ALAA-R20 was obtained after applying protoplast fusion strategy between the potent producer marine endophytic strains Streptomyces sp. ESRAA-10 (P1) and Streptomyces sp. ESRAA-31 (P2) of Dendronephthya hemprichi. Recombinant strain ALAA-R20 produced undecylprodigiosin yield higher than its parental strains ESRAA-10 and ESRAA-31 by 82.45% and 105.52% under submerged fermentation using modified R2YE medium. In order to reduce the costs of producing undecylprodigiosin, a solid-state fermentation (SSF) was applied. Scaled-up of optimized SSF parameters consisting of groundnut oil cake (GOC) sized to 3 mm, initial moisture content 80% with a mixture of dairy mill and fruit processing wastewaters (1:1), pH 7.0, inoculum size equal to 3 × 105 spores/g dry substrate (gds), incubation temperature 30 °C, and 7-day incubation period yielded the highest yield of 181.78 mg/gds of undecylprodigiosin by the recombinant strain Streptomyces sp. ALAA-R20. Extraction and purification of the pigment using the chromatographic techniques as well as mass spectral analysis exhibited maximum absorbance at 539 nm which is physiological property of the undecylprodigiosin. Undecylprodigiosin was stable over a wide temperature ranged from - 20 to 35 °C even after storage for 6 months. The maximum yield and stability of pigment was obtained at the acidic pH (acidified methanol, pH 4.0). Undecylprodigiosin obtained from the recombinant strain Streptomyces sp. ALAA-R20 demonstrated strong antimicrobial activity against all multidrug-resistant bacterial and fungal strains tested with minimum inhibitory, minimum bactericidal, and minimum fungicidal concentrations ranged between 0.5 and 4.0, 0.5 to 4.0, and 1.0 to 8.0 µg/mL, respectively. It also showed complete inhibition of cancer cells; HCT-116, HepG-2, MCF-7 and A-549 at 5, 8, 4, and 7 µM with IC50 equal to 2.0, 4.7, 1.2, and 2.8 µM, respectively.


Assuntos
Meios de Cultura , Prodigiosina/análogos & derivados , Streptomyces , Fermentação , Microrganismos Geneticamente Modificados/metabolismo , Prodigiosina/biossíntese , Streptomyces/genética , Streptomyces/metabolismo
6.
Eur J Pharmacol ; 889: 173592, 2020 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-32979354

RESUMO

Prodiginines and tambjamines are anion-selective ionophores capable of facilitating the transport of anions across the plasma membrane in mammalian cells. One of the potential applications of these anionophores is the possibility of employing them as a substitutive therapy for pathologies involving anion channels, as in cystic fibrosis. We have studied the interaction of a large anion as gluconate with three prodiginine- and two tambjamine-like compounds. Apparent dissociation constants for the chloride, iodide and gluconate complexes were estimated from iodide influx experiments in mammalian cells exposed to different extracellular anion combinations. Our experiments indicate that gluconate is not transported by the prodiginines, leaving the anionophores free to transport chloride and iodide. Conversely, gluconate would be transported to some extent by the tambjamines, competing with halides for the anionophores, and consequently reducing their flux. This might be related to the different structural features of both families of compounds. These data have important implications for the selection of impermeable anions in the analysis of the anionophore mechanism.


Assuntos
Proteínas de Transporte de Ânions/metabolismo , Prodigiosina/análogos & derivados , Pirróis/metabolismo , Animais , Proteínas de Transporte de Ânions/química , Gluconatos/metabolismo , Transporte de Íons/fisiologia , Prodigiosina/química , Prodigiosina/metabolismo , Pirróis/química , Ratos , Ratos Endogâmicos F344
7.
Int J Mol Sci ; 21(17)2020 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-32899258

RESUMO

Atherosclerosis is a chronic inflammatory disease, whose progression and stability are modulated, among other factors, by an innate and adaptive immune response. Prodiginines are bacterial secondary metabolites with antiproliferative and immunomodulatory activities; however, their effect on the progression or vulnerability of atheromatous plaque has not been evaluated. This study assessed the therapeutic potential of prodigiosin and undecylprodigiosin on inflammatory marker expression and atherosclerosis. An in vitro and in vivo study was carried out. Migration, low-density lipoprotein (LDL) uptake and angiogenesis assays were performed on cell types involved in the pathophysiology of atherosclerosis. In addition, male LDL receptor null (Ldlr-/-) C57BL/6J mice were treated with prodigiosin or undecylprodigiosin for 28 days. Morphometric analysis of atherosclerotic plaques, gene expression of atherogenic factors in the aortic sinus and serum cytokine quantification were performed. The treatments applied had slight effects on the in vitro tests performed, highlighting the inhibitory effect on the migration of SMCs (smooth muscle cells). On the other hand, although no significant difference in atherosclerotic plaque progression was observed, gene expression of IL-4 and chemokine (C-C motif) ligand 2 (Ccl2) was downregulated. In addition, 50 µg/Kg/day of both treatments was sufficient to inhibit circulating tumor necrosis factor alpha (TNF-α), interleukin-2 (IL-2) and interferon-gamma (IFN-γ) in serum. These results suggested that prodigiosin and undecylprodigiosin modulated inflammatory markers and could have an impact in reducing atherosclerotic plaque vulnerability.


Assuntos
Aterosclerose/imunologia , Regulação da Expressão Gênica/efeitos dos fármacos , Imunidade/efeitos dos fármacos , Prodigiosina/análogos & derivados , Receptores de LDL/fisiologia , Animais , Aterosclerose/tratamento farmacológico , Aterosclerose/patologia , Citocinas/metabolismo , Imunossupressores/farmacologia , Lipídeos/sangue , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Prodigiosina/farmacologia
8.
Eur J Pharmacol ; 888: 173465, 2020 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-32814079

RESUMO

Melanoma is a type of skin cancer with an elevated incidence of metastasis and chemoresistance. Such features hamper treatment success of these neoplasms, demanding the search for new therapeutic options. Using a two-step resin-based approach, we recently demonstrated that cytotoxic prodiginines bind to the inhibitor of apoptosis protein, survivin. Herein, we explore the role of survivin in melanoma and whether its modulation is related to the antimelanoma properties of three cytotoxic prodiginines (prodigiosin, cyclononylprodigiosin, and nonylprodigiosin) isolated from marine bacteria. In melanoma patients and cell lines, survivin is overexpressed, and higher levels negatively impact survival. All three prodiginines caused a decrease in cell growth with reduced cytotoxicity after 24 h compared to 72 h treatment, suggesting that low concentrations promote cytostatic effects in SK-Mel-19 (BRAF mutant) and SK-Mel-28 (BRAF mutant), but not in SK-Mel-147 (NRAS mutant). An increase in G1 population was observed after 24 h treatment with prodigiosin and cyclononylprodigiosin in SK-Mel-19. Further studies indicate that prodigiosin induced apoptosis and DNA damage, as detected by increased caspase-3 cleavage and histone H2AX phosphorylation, further arguing for the downregulation of survivin. Computer simulations suggest that prodigiosin and cyclononylprodigiosin bind to the BIR domain of survivin. Moreover, knockdown of survivin increased long-term toxicity of prodigiosin, as observed by reduced clonogenic capacity, but did not alter short-term cytotoxicity. In summary, prodiginine treatment provoked cytostatic rather than cytotoxic effects, cell cycle arrest at G0/G1 phase, induction of apoptosis and DNA damage, downregulation of survivin, and decreased clonogenic capacity in survivin knockdown cells.


Assuntos
Melanoma/metabolismo , Prodigiosina/análogos & derivados , Prodigiosina/farmacologia , Survivina/antagonistas & inibidores , Survivina/biossíntese , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/fisiologia , Dano ao DNA/efeitos dos fármacos , Dano ao DNA/fisiologia , Relação Dose-Resposta a Droga , Regulação para Baixo/efeitos dos fármacos , Regulação para Baixo/fisiologia , Humanos , Melanoma/tratamento farmacológico , Prodigiosina/uso terapêutico , Survivina/genética
9.
Cells ; 9(8)2020 07 22.
Artigo em Inglês | MEDLINE | ID: mdl-32708048

RESUMO

Resistance of cancer cells to tumor necrosis factor-related apoptosis-inducing ligand (TRAIL)-induced apoptosis represents the major hurdle to the clinical use of TRAIL or its derivatives. The discovery and development of lead compounds able to sensitize tumor cells to TRAIL-induced cell death is thus likely to overcome this limitation. We recently reported that marine actinomycetes' crude extracts could restore TRAIL sensitivity of the MDA-MB-231 resistant triple negative breast cancer cell line. We demonstrate in this study, that purified secondary metabolites originating from distinct marine actinomycetes (sharkquinone (1), resistomycin (2), undecylprodigiosin (3), butylcyclopentylprodigiosin (4), elloxizanone A (5) and B (6), carboxyexfoliazone (7), and exfoliazone (8)), alone, and in a concentration-dependent manner, induce killing in both MDA-MB-231 and HCT116 cell lines. Combined with TRAIL, these compounds displayed additive to synergistic apoptotic activity in the Jurkat, HCT116 and MDA-MB-231 cell lines. Mechanistically, these secondary metabolites induced and enhanced procaspase-10, -8, -9 and -3 activation leading to an increase in PARP and lamin A/C cleavage. Apoptosis induced by these compounds was blocked by the pan-caspase inhibitor QvD, but not by a deficiency in caspase-8, FADD or TRAIL agonist receptors. Activation of the intrinsic pathway, on the other hand, is likely to explain both their ability to trigger cell death and to restore sensitivity to TRAIL, as it was evidenced that these compounds could induce the downregulation of XIAP and survivin. Our data further highlight that compounds derived from marine sources may lead to novel anti-cancer drug discovery.


Assuntos
Actinobacteria/metabolismo , Organismos Aquáticos/metabolismo , Regulação para Baixo/efeitos dos fármacos , Descoberta de Drogas/métodos , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Metabolismo Secundário/fisiologia , Survivina/metabolismo , Ligante Indutor de Apoptose Relacionado a TNF/farmacologia , Proteínas Inibidoras de Apoptose Ligadas ao Cromossomo X/metabolismo , Apoptose/efeitos dos fármacos , Benzopirenos/metabolismo , Benzopirenos/farmacologia , Caspase 8/genética , Sobrevivência Celular/efeitos dos fármacos , Deleção de Genes , Células HCT116 , Humanos , Células Jurkat , Oxazinas/metabolismo , Oxazinas/farmacologia , Prodigiosina/análogos & derivados , Prodigiosina/metabolismo , Prodigiosina/farmacologia , Quinonas/metabolismo , Quinonas/farmacologia
10.
Drug Discov Today ; 25(5): 828-836, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32251776

RESUMO

Prodigiosin (PG), a red tripyrrole pigment, belongs to a member of the prodiginine family and is normally secreted by various sources including Serratia marcescens and other Gram-negative bacteria. The studies of PG have received innovative devotion as a result of reported antimicrobial, larvicidal and anti-nematoid immunomodulation and antitumor properties, owing to its antibiotic and cytotoxic activities. This review provides a comprehensive summary of research undertaken toward the isolation and structural elucidation of the prodiginine family of natural products. Additionally, the current evidence-based understanding of the biological activities and medicinal potential of PG is employed to determine the efficacy, with some reports of information related to pharmacokinetics, pharmacodynamics and toxicology.


Assuntos
Prodigiosina/biossíntese , Prodigiosina/farmacologia , Animais , Produtos Biológicos/farmacologia , Humanos , Prodigiosina/análogos & derivados , Serratia marcescens/metabolismo
11.
Cell Chem Biol ; 26(8): 1133-1142.e4, 2019 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-31155509

RESUMO

Identification of RNA-interacting pharmacophores could provide chemical probes and, potentially, small molecules for RNA-based therapeutics. Using a high-throughput differential scanning fluorimetry assay, we identified small-molecule natural products with the capacity to bind the discrete stem-looped structure of pre-miR-21. The most potent compound identified was a prodiginine-type compound, butylcycloheptyl prodiginine (bPGN), with the ability to inhibit Dicer-mediated processing of pre-miR-21 in vitro and in cells. Time-dependent RT-qPCR, western blot, and transcriptomic analyses showed modulation of miR-21 expression and its target genes such as PDCD4 and PTEN upon treatment with bPGN, supporting on-target inhibition. Consequently, inhibition of cellular proliferation in HCT-116 colorectal cancer cells was also observed when treated with bPGN. The discovery that bPGN can bind and modulate the expression of regulatory RNAs such as miR-21 helps set the stage for further development of this class of natural product as a molecular probe or therapeutic agent against miRNA-dependent diseases.


Assuntos
Produtos Biológicos/farmacologia , MicroRNAs/antagonistas & inibidores , Prodigiosina/análogos & derivados , Sítios de Ligação/efeitos dos fármacos , Produtos Biológicos/química , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Células HCT116 , Humanos , MicroRNAs/metabolismo , Estrutura Molecular , Imagem Óptica , Prodigiosina/química , Prodigiosina/farmacologia , Relação Estrutura-Atividade , Células Tumorais Cultivadas
12.
Appl Microbiol Biotechnol ; 103(7): 2873-2887, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30761415

RESUMO

Prodiginines are a large family of tripyrrole alkaloids that contain natural members produced by various bacteria and non-natural members obtained from chemical synthesis, enzymatic synthesis, and mutasynthesis. These compounds have attracted a great deal of attention due to their wide range of fascinating properties including anti-infective, anticancer, and immunosuppressive activities. In consideration of the great need for novel and effective anti-infective agents, this review is mainly focused on the current status of research on the anti-infective properties of prodiginines, highlighting their antibacterial, antifungal, antiprotozoal, anti-larval, and antiviral activities. Additionally, the multiple mechanisms by which prodiginines exert their anti-infective effects will also be discussed.


Assuntos
Anti-Infecciosos/farmacologia , Prodigiosina/análogos & derivados , Animais , Antibacterianos/farmacologia , Antifúngicos/farmacologia , Antiprotozoários/farmacologia , Antivirais/farmacologia , Bactérias/efeitos dos fármacos , Fungos/efeitos dos fármacos , Imunossupressores/farmacologia , Controle de Mosquitos , Parasitos/efeitos dos fármacos , Prodigiosina/farmacologia , Vírus/efeitos dos fármacos
13.
DNA Cell Biol ; 37(6): 535-542, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29672160

RESUMO

The search for new chemotherapeutics unaffected by efflux pumps would significantly increase life expectancy in patients with malignant cancers. In this study, butylcycloheptylprodigiosin and undecylprodigiosin were HPLC-purified and verified, using nuclear magnetic resonance spectroscopy. Cell cytotoxicity and transportation kinetics on multiple-drug resistance (MDR) cells were evaluated. Daunorubicin and butylcycloheptylprodigiosin were less toxic in the MDR1 overexpressing line, but undecylprodigiosin revealed potent toxicity toward MDR1 and BCRP expressing malignant cells. There was no noticeable change in MDR1 and BCRP transcripts during 3 days of treatment with prodiginines. While daunorubicin and mitoxantrone uptake from the cell environment significantly decreased with increasing multidrug resistance up to 46% and 62%, respectively, the accumulation of undecylprodigiosin and to a lesser extent butylcycloheptylprodigiosin in the resistance cells occurred cell- and dose-dependently via a passive diffusion process and were almost equally sensitive to the parent lines. The efflux of xenobiotics commenced immediately with different kinetics in various cells. A greater amount of daunorubicin and mitoxantrone were rapidly thrown out of their corresponding MDR cells in the absence of the specific inhibitor (3.01 and 1.81 dF/min, respectively) and represented functional efflux pumps. MDR pumps did not apparently influence undecylprodigiosin efflux patterns; but butylcycloheptylprodigiosin was partially removed from EPG85.257RDB cells at the rate of 2.66 and 1.41 dF/min in the absence and presence of verapamil, respectively.


Assuntos
Membro 1 da Subfamília B de Cassetes de Ligação de ATP/metabolismo , Membro 2 da Subfamília G de Transportadores de Cassetes de Ligação de ATP/metabolismo , Resistência a Múltiplos Medicamentos/efeitos dos fármacos , Proteínas de Neoplasias/metabolismo , Prodigiosina/análogos & derivados , Antineoplásicos/farmacologia , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Humanos , Células MCF-7 , Estrutura Molecular , Neoplasias/metabolismo , Neoplasias/patologia , Prodigiosina/química , Prodigiosina/farmacologia , Streptomyces/química
14.
Nat Prod Rep ; 35(7): 622-632, 2018 07 18.
Artigo em Inglês | MEDLINE | ID: mdl-29651484

RESUMO

Covering: up to the end of 2017 The roles played by Rieske non-heme iron-dependent oxygenases in natural product biosynthesis are reviewed, with particular focus on experimentally characterised examples. Enzymes belonging to this class are known to catalyse a range of transformations, including oxidative carbocyclisation, N-oxygenation, C-hydroxylation and C-C desaturation. Examples of such enzymes that have yet to be experimentally investigated are also briefly described and their likely functions are discussed.


Assuntos
Produtos Biológicos/metabolismo , Complexo III da Cadeia de Transporte de Elétrons/química , Oxigenases/química , Oxigenases/metabolismo , Ciclização , Complexo III da Cadeia de Transporte de Elétrons/metabolismo , Heme , Compostos Heterocíclicos com 3 Anéis/química , Compostos Heterocíclicos com 3 Anéis/metabolismo , Hidroxilação , Prodigiosina/análogos & derivados , Prodigiosina/biossíntese , Prodigiosina/química , Pirróis/química , Pirróis/metabolismo , Pirrolnitrina/biossíntese , Compostos de Espiro/metabolismo
15.
Phytochemistry ; 145: 57-67, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29091816

RESUMO

Alphaproteobacterium strain MOLA1416, related to Mycoplana ramosa DSM 7292 and Chelativorans intermedius CC-MHSW-5 (93.6% 16S rRNA sequence identity) was isolated from the marine lichen, Lichina pygmaea and its chemical composition was characterized by a metabolomic network analysis using LC-MS/MS data. Twenty-five putative different compounds were revealed using a dereplication workflow based on MS/MS signatures available through GNPS (https://gnps.ucsd.edu/). In total, ten chemical families were highlighted including isocoumarins, macrolactones, erythrinan alkaloids, prodiginines, isoflavones, cyclohexane-diones, sterols, diketopiperazines, amino-acids and most likely glucocorticoids. Among those compounds, two known metabolites (13 and 26) were isolated and structurally identified and metabolite 26 showed a high cytotoxic activity against B16 melanoma cell lines with an IC50 0.6 ± 0.07 µg/mL.


Assuntos
Alphaproteobacteria/química , Líquens/microbiologia , Melanoma Experimental/tratamento farmacológico , Oligopeptídeos/química , Prodigiosina/análogos & derivados , Alphaproteobacteria/isolamento & purificação , Alphaproteobacteria/metabolismo , Animais , Linhagem Celular , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Humanos , Líquens/metabolismo , Melanoma Experimental/patologia , Camundongos , Estrutura Molecular , Oligopeptídeos/isolamento & purificação , Prodigiosina/química , Prodigiosina/isolamento & purificação , Prodigiosina/farmacologia , Relação Estrutura-Atividade
16.
Microb Pathog ; 110: 214-224, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28648623

RESUMO

Owing to the importance of endophytes, current research was aimed to purify the secondary metabolites from targeted source. Ferula sumbul, a lipophilic extract of the endophyte was prepared in 10% methanol and partitioned with ethyl acetate and bioassay guided isolation was carried using standard protocols against bacterial, fungal and cancer cells. The active fractions consisted of three new metabolites (2-methyl-3-nonyl prodiginine, Bis (2-ethylhexyl) phthalate, and a meroterpenoid, Preaustinoid A). Their structures were confirmed with LCMS/MS. The purified metabolites showed valuable results against tested activities which concluded that these compounds have great potential and these may be applicable to textile (dyeing), pharmaceutical (drug, infectious agents) and food (preservatives) industries. This study reveals the potential of E. nigrum as an important source of bioactive compounds including 2-methyl-3-nonyl prodiginine, Bis (2-ethylhexyl) phthalate, and Preaustinoid A. This is first report of isolation of prodiginines as well as meroterpenoid and Bis (2-ethylhexyl) phthalate from Epicoccum nigrum.


Assuntos
Anti-Infecciosos/química , Antineoplásicos/química , Ascomicetos/metabolismo , Endófitos/metabolismo , Ferula/microbiologia , Anti-Infecciosos/isolamento & purificação , Anti-Infecciosos/farmacologia , Antineoplásicos/isolamento & purificação , Antineoplásicos/farmacologia , Ascomicetos/química , Bactérias/efeitos dos fármacos , Linhagem Celular Tumoral/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Endófitos/química , Endófitos/classificação , Fungos/efeitos dos fármacos , Humanos , Concentração Inibidora 50 , Melanoma , Ácidos Ftálicos/química , Ácidos Ftálicos/farmacologia , Filogenia , Raízes de Plantas/microbiologia , Prodigiosina/análogos & derivados , Prodigiosina/química , Prodigiosina/farmacologia , Terpenos/química , Terpenos/farmacologia
17.
Appl Environ Microbiol ; 83(6)2017 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-28062460

RESUMO

Gram-positive Streptomyces bacteria produce thousands of bioactive secondary metabolites, including antibiotics. To systematically investigate genes affecting secondary metabolism, we developed a hyperactive transposase-based Tn5 transposition system and employed it to mutagenize the model species Streptomyces coelicolor, leading to the identification of 51,443 transposition insertions. These insertions were distributed randomly along the chromosome except for some preferred regions associated with relatively low GC content in the chromosomal core. The base composition of the insertion site and its flanking sequences compiled from the 51,443 insertions implied a 19-bp expanded target site surrounding the insertion site, with a slight nucleic acid base preference in some positions, suggesting a relative randomness of Tn5 transposition targeting in the high-GC Streptomyces genome. From the mutagenesis library, 724 mutants involving 365 genes had altered levels of production of the tripyrrole antibiotic undecylprodigiosin (RED), including 17 genes in the RED biosynthetic gene cluster. Genetic complementation revealed that most of the insertions (more than two-thirds) were responsible for the changed antibiotic production. Genes associated with branched-chain amino acid biosynthesis, DNA metabolism, and protein modification affected RED production, and genes involved in signaling, stress, and transcriptional regulation were overrepresented. Some insertions caused dramatic changes in RED production, identifying future targets for strain improvement.IMPORTANCE High-GC Gram-positive streptomycetes and related actinomycetes have provided more than 100 clinical drugs used as antibiotics, immunosuppressants, and antitumor drugs. Their genomes harbor biosynthetic genes for many more unknown compounds with potential as future drugs. Here we developed a useful genome-wide mutagenesis tool based on the transposon Tn5 for the study of secondary metabolism and its regulation. Using Streptomyces coelicolor as a model strain, we found that chromosomal insertion was relatively random, except at some hot spots, though there was evidence of a slightly preferred 19-bp target site. We then used prodiginine production as a model to systematically survey genes affecting antibiotic biosynthesis, providing a global view of antibiotic regulation. The analysis revealed 348 genes that modulate antibiotic production, among which more than half act to reduce production. These might be valuable targets in future investigations of regulatory mechanisms, for strain improvement, and for the activation of silent biosynthetic gene clusters.


Assuntos
Antibacterianos/biossíntese , Elementos de DNA Transponíveis/genética , Prodigiosina/análogos & derivados , Metabolismo Secundário/genética , Streptomyces coelicolor/genética , Transposases/genética , Composição de Bases/genética , Sequência de Bases , Regulação Bacteriana da Expressão Gênica , Biblioteca Gênica , Mutagênese Insercional , Prodigiosina/biossíntese
20.
Exp Toxicol Pathol ; 69(1): 55-62, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-27843060

RESUMO

It is known that some bacterial species are more resilient to different kinds of irradiation due to the naturally developed protective mechanisms and compounds such as pigments. On the other hand, reasoned tissue engineering using plasma remains a critical task and requires very precise control of plasma parameters in order to mitigate its potential detrimental effects. Here we isolated a natural protective agent, microbially produced undecylprodigiosin ((5'Z)-4'-methoxy-5'-[(5-undecyl-1H-pyrrol-2-yl)methylene]-1H,5'H-2,2'-bipyrrole), and investigated its effects on human blood cells independently and in combination with plasma. Two approaches were applied; the first, undecylprodigiosin (UP pigment) was added to the blood cultures, which then were exposed to plasma (pre-treatment); and the second- the blood cultures were exposed to plasma and then treated with pigment (post-treatment). The interactions of plasma and UP pigment with blood cells were investigated by conducting a series of biological tests providing the information regarding their genotoxicity, cytotoxicity and redox modulating activities. The exposure of cells to plasma induced oxidative stress as well as certain genotoxic and cytotoxic effects seen as elevated micronuclei incidence, decreased cell proliferation and enhanced apoptosis. In blood cultures treated with UP pigment alone, we found that both cytotoxic and protective effects could be induced depending on the concentration used. The highest UP pigment concentration increased lipid peroxidation and the incidence of micronuclei by more than 70% with maximal suppression of cell proliferation. On the contrary, we found that the lowest UP pigment concentration displayed protective effects. In combined treatments with plasma and UP pigment, we found that UP pigment could provide spatial shielding to plasma exposure. In the pre-treatment approach, the incidence of micronuclei was reduced by 35.52% compared to control while malondialdehyde level decreased by 36% indicating a significant mitigation of membrane damage induced by plasma. These results open perspectives for utilizing UP pigment for protection against overexposures in the field of plasma medicine.


Assuntos
Antioxidantes/farmacologia , Células Sanguíneas/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Prodigiosina/análogos & derivados , Protetores contra Radiação/farmacologia , Células Sanguíneas/efeitos da radiação , Dano ao DNA/efeitos dos fármacos , Humanos , Técnicas In Vitro , Peroxidação de Lipídeos/efeitos dos fármacos , Prodigiosina/farmacologia
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