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Aralia continentalis has been used in Korea as a folk remedy for arthralgia, rheumatism, and inflammation. However, its anti-lymphoma effect remains uncharacterized. Here, we demonstrate that A. continentalis extract and its three diterpenes efficiently kill B-lymphoma cells. Our in vitro and in vivo results suggest that the cytotoxic activities of continentalic acid, a major diterpene from A. continentalis extract, are specific towards cancer cells while leaving normal murine cells and tissues unharmed. Mechanistically, continentalic acid represses the expression of pro-survival Bcl-2 family members, such as Mcl-1 and Bcl-xL. It dissociates the mitochondrial membrane potential, leading to the stimulation of effector caspase 3/7 activities and, ultimately, cell death. Intriguingly, this agent therapeutically synergizes with roflumilast, a pan-PDE4 inhibitor that has been successfully repurposed for the treatment of aggressive B-cell malignancies in recent clinical tests. Our findings unveiled that A. continentalis extract and three of the plant's diterpenes exhibit anti-cancer activities. We also demonstrate the synergistic inhibitory effect of continentalic acid on the survival of B-lymphoma cells when combined with roflumilast. Taken in conjunction, continentalic acid may hold significant potential for the treatment of B-cell lymphoma.
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Antineoplásicos/farmacologia , Diterpenos/farmacologia , Linfoma de Células B/tratamento farmacológico , Animais , Apoptose/efeitos dos fármacos , Aralia/química , Linhagem Celular Tumoral , Humanos , Linfoma de Células B/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Camundongos Nus , Extratos Vegetais/farmacologia , Raízes de Plantas/química , República da CoreiaRESUMO
The members of the Burkholderia genus are characterized by high versatility and adaptability to various ecological niches. With the availability of the genome sequences of numerous species of Burkholderia, many studies have been conducted to elucidate the unique features of this exceptional group of bacteria. Genomic and metabolic plasticity are common among Burkholderia species, as evidenced by their relatively large multi-replicon genomes that are rich in insertion sequences and genomic islands and contain a high proportion of coding regions. Such unique features could explain their adaptability to various habitats and their versatile lifestyles, which are reflected in a multiplicity of species including free-living rhizospheric bacteria, plant endosymbionts, legume nodulators, and plant pathogens. The phytopathogenic Burkholderia group encompasses several pathogens representing threats to important agriculture crops such as rice. Contrarily, plant-beneficial Burkholderia have also been reported, which have symbiotic and growth-promoting roles. In this review, the taxonomy of Burkholderia is discussed emphasizing the recent updates and the contributions of genomic studies to precise taxonomic positioning. Moreover, genomic and functional studies on Burkholderia are reviewed and insights are provided into the mechanisms underlying the virulence and benevolence of phytopathogenic and plant-beneficial Burkholderia, respectively, on the basis of cutting-edge knowledge.
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Burkholderia/genética , Produtos Agrícolas/microbiologia , Genoma Bacteriano , Interações Hospedeiro-Patógeno , Burkholderia/classificação , Burkholderia/patogenicidade , Filogenia , SimbioseRESUMO
Members of the genus Burkholderia occupy remarkably diverse niches, with genome sizes ranging from ~3.75 to 11.29 Mbp. The genome of Burkholderia glumae ranges in size from ~5.81 to 7.89 Mbp. Unlike other plant pathogenic bacteria, B. glumae can infect a wide range of monocot and dicot plants. Comparative genome analysis of B. glumae strains can provide insight into genome variation as well as differential features of whole metabolism or pathways between multiple strains of B. glumae infecting the same host. Comparative analysis of complete genomes among B. glumae BGR1, B. glumae LMG 2196, and B. glumae PG1 revealed the largest departmentalization of genes onto separate replicons in B. glumae BGR1 and considerable downsizing of the genome in B. glumae LMG 2196. In addition, the presence of large-scale evolutionary events such as rearrangement and inversion and the development of highly specialized systems were found to be related to virulence-associated features in the three B. glumae strains. This connection may explain why this bacterium broadens its host range and reinforces its interaction with hosts.
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Evolução Biológica , Burkholderia/genética , Genoma Bacteriano , Genômica , Burkholderia/classificação , Burkholderia/metabolismo , Rearranjo Gênico , Estudo de Associação Genômica Ampla , Genômica/métodos , Redes e Vias Metabólicas , Doenças das Plantas/microbiologia , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Virulência/genéticaRESUMO
Three new triterpene glycosides ursan-3ß,19α,22ß-triol-3-O-ß-D-glucopyranosyl (2'â1â³)-ß-D-glucopyranoside (1), ursan-3α,11ß-diol-3-O-α-D-glucopyranosyl-(6'â1â³)-α-D-glucopyranosyl-(6â³â1â´)-α-D-glucopyranosyl-(6â´â1â´')-α-D-glucopyranoside (2) and lanost-5,24-dien-3ß-ol-3-O-ß-D-glucopyranosyl-(6'â1â³)-ß-D-glucopyranosyl-(6â³â1â´)-ß-D-glucopyranoside (3), together with one known compound were isolated and identified from the marc of red ginseng. Their structures were elucidated by spectroscopic data analysis. Compounds (1-3) were investigated for anti-inflammatory effects using the RAW 264.7 macrophage cell line. In the cell proliferation assay, lipopolysaccharide stimulation decreased cell proliferation of RAW 264.7 macrophage cells, but the suppression of cell proliferation was significantly protected by treatment with compounds 2 and 3. Compounds 2 and 3 had a suppressive effect on the production of nitric oxide (NO), and they inhibited mRNA expression of proinflammatory mediators such as inducible nitric oxide synthase, and cyclooxygenase-2, and proinflammatory cytokines such as two interleukins and tumor necrosis factor-α. These findings suggest that compounds 2 and 3 have potential anti-inflammatory activities.
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Anti-Inflamatórios/farmacologia , Glicosídeos/farmacologia , Macrófagos/efeitos dos fármacos , Panax/química , Triterpenos/farmacologia , Animais , Anti-Inflamatórios/química , Anti-Inflamatórios/isolamento & purificação , Sobrevivência Celular/efeitos dos fármacos , Ciclo-Oxigenase 2/metabolismo , Citocinas/antagonistas & inibidores , Citocinas/imunologia , Citocinas/metabolismo , Relação Dose-Resposta a Droga , Glicosídeos/química , Glicosídeos/isolamento & purificação , Lipopolissacarídeos/antagonistas & inibidores , Lipopolissacarídeos/farmacologia , Macrófagos/imunologia , Macrófagos/metabolismo , Camundongos , Conformação Molecular , Óxido Nítrico/antagonistas & inibidores , Óxido Nítrico/biossíntese , Óxido Nítrico Sintase Tipo II/antagonistas & inibidores , Óxido Nítrico Sintase Tipo II/metabolismo , Relação Estrutura-Atividade , Triterpenos/química , Triterpenos/isolamento & purificaçãoRESUMO
A new method is presented for synthesizing arbutin glycosides using α-glucosidase (AglA) from Thermoplasma acidophilum and its glycosynthase mutant. An α-glycosynthase was constructed by substituting the catalytic nucleophile with the non-nucleophile glycine. Enzyme activity was then recovered using an external nucleophile. The transglycosylation reaction of AglA using maltose as a donor and arbutin as an acceptor produced arbutin coupled with a glucose moiety. The products were isolated and further analysed using preparative recycling HPLC. Arbutin glycosides linked to C-3, C-4, and C-6 were identified using NMR. The transglycosylation products of AglA were used as substrates for the enzyme reaction, which were hydrolyzed back again and reduced final yields. The glycosynthase mutant produced one main arbutin glycoside linked to C-4 with a yield of 38 % without further observed hydrolysis.
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Arbutina/metabolismo , Glicoconjugados/metabolismo , Thermoplasma/enzimologia , alfa-Glucosidases/metabolismo , Biotransformação , Cromatografia Líquida de Alta Pressão , Espectroscopia de Ressonância Magnética , Maltose/metabolismo , Proteínas Mutantes/genética , Proteínas Mutantes/isolamento & purificação , Proteínas Mutantes/metabolismo , Thermoplasma/genética , alfa-Glucosidases/genética , alfa-Glucosidases/isolamento & purificaçãoRESUMO
In this study, waxy corn starch was modified with 230 U or 460 U of amylosucrase (AS) from Neisseria polysaccharea (NP) to elongate the glucan. The amylose content of the AS-modified starches was determined using iodine and concanavalin A (Con A) methods, and their in vivo digestion, thermal, swelling, and pasting properties were evaluated. The amylose content of AS-treated starches was not significantly different (p > 0.05) when using the Con A method but was significantly higher than that of non-AS-treated samples when using the iodine method. In vivo, rats fed AS-treated starch had significantly lower blood glucose levels at 15 min than other rats; rats fed 460 U AS had lower blood glucose levels at 30 and 60 min than non-AS-treated rats. DSC analysis revealed that AS-treated starches exhibited higher initial, melting, and completion temperatures. Minimal volume expansion was observed by swelling factor analysis, while a Rapid Visco Analyzer assessment revealed that they had higher pasting onset temperatures, lower peak viscosities, and no trough viscosity compared to native starch. The elongated glucans in AS-treated starch reinforced their crystalline structure and increased slowly digestible and enzyme-resistant starch content. Overall, AS-treated starch showed unique thermal properties and a reduced blood glucose index upon administration. This distinctive characteristic of NPAS-treated starch makes it a good candidate food or non-food material for cosmetic products, medical materials, and adhesives.
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Traditional Korean fermented soy paste (doenjang) has various health benefits; however, its intense umami flavor might interfere with global acceptance. Herbs-supplemented (HS) doenjang, coriander (CS), Korean mint (KMS), and peppermint (PMS), during fermentation was evaluated for its organoleptic properties. The levels of most free amino acids in HS doenjang, known to impart intense flavor, were decreased, including aspartic acid and glutamine. γ-Aminobutyric acid levels increased, whereas 2-pentylfuran levels significantly decreased in KMS and PMS doenjang (p < 0.05). The decrease in the levels of total free sugars, especially glucose, acetic acid, and fumaric acid, and the increase in lactic acid levels reflected in the desirable sour taste. Sensory evaluation corresponded to these alterations, judged superior most of sensorial attributes both by the Korean and foreigner panel particularly in KMS doenjang. Changed amount of chemical components, e.g. asparagine and glutamine of HS doenjang decreased strong umami flavor, it further affected sensory properties.
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Triclosan (TCS) is a widely used antimicrobial agent found at high concentrations in biosolids produced during municipal wastewater treatment. The effect of adding TCS, in the presence or absence of biosolids, on the composition of an agricultural soil microbial community was measured using phospholipid fatty acid analysis (PLFA). Most changes observed in microbial community composition were attributable to the addition of biosolids or to the passage of time, with smaller changes due to TCS exposure, regardless of the presence of biosolids. TCS slightly reduced the relative abundance of Gram-positive and Gram-negative bacteria and fungi, with or without biosolids. Bacteria were more sensitive than eukaryotes, consistent with the mode of action of TCS, which selectively targets fatty acid synthesis and disrupts cell membranes of bacteria. TCS slightly increased biomarkers of microbial stress, but stress biomarkers were lower in all biosolid treated soils, presumably due to increased availability of nutrients mitigating potential TCS toxicity.
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Agricultura , Triclosan/toxicidade , Bactérias/efeitos dos fármacos , Bactérias/metabolismo , Ácidos Graxos/química , Ácidos Graxos/metabolismo , Fungos/efeitos dos fármacos , Fungos/metabolismo , Fosfolipídeos/química , Fosfolipídeos/metabolismo , Solo/química , Poluentes do Solo/toxicidadeRESUMO
Doenjang (fermented soybean paste) and ganjang (soy sauce) are traditional fermented foods that are widely consumed in Korea. The oligosaccharides found in soybean and its fermented foods have great potential to improve the quality of foods; however, their structural details have not been well studied. In this study, we used advanced mass spectrometry and gas chromatography to analyze oligosaccharides and their monomeric composition in two fermented soybean products. In both foods, oligosaccharides with a degree of polymerization ranging from 3 to 7 were found. Their constituent monosaccharides were characterized; galactose, xylose, arabinose, and rhamnose were the predominant constituents of the oligosaccharides, and fucose, fructose, mannose, glucose, and N-acetylglucosamine were also found. The great structural diversity of the oligosaccharides found suggests that soybean carbohydrates are hydrolyzed and/or transformed during fermentation and may yield novel oligosaccharides.
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Alimentos Fermentados , Alimentos de Soja , Glycine max/química , Cromatografia Gasosa-Espectrometria de Massas , Oligossacarídeos , Fermentação , Espectrometria de Massas , Alimentos de Soja/análise , Alimentos Fermentados/análise , República da CoreiaRESUMO
The viable community of microorganisms in the rhizosphere significantly impacts the physiological development and vitality of plants. The assembly and functional capacity of the rhizosphere microbiome are greatly influenced by various factors within the rhizosphere. The primary factors are the host plant genotype, developmental stage and status, soil properties, and resident microbiota. These factors drive the composition, dynamics, and activity of the rhizosphere microbiome. This review addresses the intricate interplay between these factors and how it facilitates the recruitment of specific microbes by the host plant to support plant growth and resilience under stress. This review also explores current methods for engineering and manipulating the rhizosphere microbiome, including host plant-mediated manipulation, soil-related methods, and microbe-mediated methods. Advanced techniques to harness the plant's ability to recruit useful microbes and the promising use of rhizo-microbiome transplantation are highlighted. The goal of this review is to provide valuable insights into the current knowledge, which will facilitate the development of cutting-edge strategies for manipulating the rhizosphere microbiome for enhanced plant growth and stress tolerance. The article also indicates promising avenues for future research in this field.
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Three types of doenjang, a fermented soybean paste, were prepared by adding coriander (CR), Korean mint (KM), and peppermint (PM) and compared to the control group (CN) by studying their metabolite profiles and antioxidant activities followed by different fermentation periods (1, 30, and 150 days, respectively). The primary metabolome was analyzed by GC-TOF-MS, and 36 of metabolites were identified in four types of doenjang samples (CN, CR, KM, and PM). Samples were clustered based on the herb type and fermentation period in PCA and PLS-DA analysis. For the secondary metabolome analysis, UHPLC-Q-orbitrap-MS was used, and 26 metabolites were identified. The statistical analysis showed that the samples were clustered by herb type rather than fermentation period, and the samples containing KM and PM were located in the same group. The DPPH assay showed that PM-containing doenjang had the highest antioxidant activity. Correlation analysis indicated that organic acids such as lactic acid, malonic acid, succinic acid, uracil, vanillic acid, and quinic acid showed positive correlation with the DPPH activity. Overall, our results demonstrated that incorporating herbs in doenjang during fermentation caused significant shifts (p-value < 0.05) in the doenjang metabolites and antioxidant activity. Hence, herbs could be utilized for enhancing doenjang fermentation.
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Food fermentation has been practised since ancient times to improve sensory properties and food preservation. This review discusses the process of fermentation, which has undergone remarkable improvement over the years, from relying on natural microbes and spontaneous fermentation to back-slopping and the use of starter cultures. Modern biotechnological approaches, including genome editing using CRISPR/Cas9, have been investigated and hold promise for improving the fermentation process. The invention of next-generation sequencing techniques and the rise of meta-omics tools have advanced our knowledge on the characterisation of microbiomes involved in food fermentation and their functional roles. The contribution and potential advantages of meta-omics technologies in understanding the process of fermentation and examples of recent studies utilising multi-omics approaches for studying food-fermentation microbiomes are reviewed. Recent technological advances in studying food fermentation have provided insights into the ancient wisdom in the practice of food fermentation, such as the choice of substrates and fermentation conditions leading to desirable properties. This review aims to stimulate research on the process of fermentation and the associated microbiomes to produce fermented food efficiently and sustainably. Prospects and the usefulness of recent advances in molecular tools and integrated multi-omics approaches are highlighted.
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The microflora of Korean soy sauce (gangjang) play an important role in maintaining its quality and safety. Hence, it is important to study the microflora and the possible approaches to improve their composition. In this study, the effect of adding coriander during soy sauce fermentation on the microflora and biogenic amines was evaluated using metagenomics and 1H NMR analyses, respectively. The ß-diversity showed a clear distinction between the microbiota of the coriander and control groups. Microbial composition analysis revealed noticeable shifts, as Firmicutes abundance was significantly higher in the coriander group (91.77%) than that in the control (38.78%). The dominant bacterial family in the coriander group was the Bacillaceae (57.94%), while Halomonadaceae was dominant in the control group (49.77%). At the species level, Chromohalobacter beijerinckii dominated the microbial community in the control group (49.54%), but not (4.43%) in the coriander group. Moreover, there was a negative correlation between the Bacillaceae and several other bacterial families, including Halomonadaceae, which indicated a possible antagonism and partly explained the reduction in Chromohalobacter abundance in the coriander group. The levels of the biogenic amines histamine, putrescine, and tyramine, which are considered potential health risk factors, were significantly lower in the coriander soy sauce than those in the control sauce. The results of this study suggest that the addition of coriander during Korean soy sauce fermentation is beneficial, as coriander significantly reduces the levels of biogenic amines and the bacteria that produce them.
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Dracocephalum palmatum Stephan (DPS), a medicinal plant used by Russian nomads, has been known to exhibit antioxidant properties. However, to the best of our knowledge, its anticancer effect has not been elucidated. The present study aimed to evaluate the tumorsuppressive effect of DPS extract (DPSE) in diffuse large B cell lymphoma (DLBCL) and the underlying mechanism. MTS assays and Annexin V staining were performed to assess the antiproliferative and apoptotic effects of DPSE, respectively. To reveal the underlying mechanisms, the levels of pro and antiapoptotic Bcl2 members were analyzed by western blotting. Rescue experiments were performed to investigate the potential involvement of Myc in DPSEinduced tumorinhibitory effects. Additionally, highperformance liquid chromatography analysis was performed to analyze the components with anticancer effects. Exposure of multiple DLBCL cell lines to DPSE significantly decreased cell viability and increased apoptosis, whereas it had no effect on the survival of normal cells in vitro and in vivo. This indicates that its cytotoxic effect may be specific to cancer cells. Mechanistically, cell death induced by DPSE was dependent on the activation of caspase3/7 and the disruption of mitochondrial membrane potential. Treatment with the extract ameliorated the expression of antiapoptotic Bcl2 members BclxL and Mcl1, and upregulated that of proapoptotic Bcl2 members Bax and Bak. These modulations led to the disruption of mitochondrial membrane potential, which culminated in the activation of executioner caspases3 and 7. Notably, overexpression of Myc inhibited DPSEinduced cell killing, indicating the involvement of Myc in this process. Given that dysregulation of Myc is strongly associated with the pathobiology of DLBCL, the present study highlights the potential therapeutic efficacy of DPSE in patients with DLBCL with aberrant Myc expression. Furthermore, fractionation of DPSE by thin layer chromatography and liquid chromatography/mass spectrometrybased investigation of the fraction with bioactive compounds demonstrated that flavonoids may be responsible for most, if not all, of the antilymphoma effect. Efforts to identify the bioactive flavonoids is currently underway.
Assuntos
Antineoplásicos Fitogênicos/farmacologia , Lamiaceae/química , Linfoma Difuso de Grandes Células B/tratamento farmacológico , Extratos Vegetais/farmacologia , Proteínas Proto-Oncogênicas c-myc/antagonistas & inibidores , Animais , Antineoplásicos Fitogênicos/isolamento & purificação , Antineoplásicos Fitogênicos/uso terapêutico , Apoptose/efeitos dos fármacos , Caspases/metabolismo , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Humanos , Leucócitos Mononucleares , Linfoma Difuso de Grandes Células B/patologia , Masculino , Camundongos , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Extratos Vegetais/isolamento & purificação , Extratos Vegetais/uso terapêutico , Cultura Primária de Células , Proteínas Proto-Oncogênicas c-myc/metabolismo , Testes de Toxicidade Aguda , Ensaios Antitumorais Modelo de XenoenxertoRESUMO
This study investigated the impact of supplementing radish kimchi with slices of gizzard shad, Konosirus punctatus (boneless - BLGS, or whole - WGS) on the kimchi's chemical and microbial composition for different fermentation durations. Higher levels of amino nitrogen (N), calcium (Ca) and phosphorus (P) were observed in the supplemented kimchi groups compared to those in the control and further, Ca and P levels were highest in the WGS kimchi group. Microbial composition analysis revealed noticeable differences between the three groups at different fermentation durations. The predominant species changed from Leuconostoc rapi to Lactobacillus sakei at the optimal- and over-ripening stages in the control kimchi group. The predominant species in the BLGS kimchi group was L. rapi at all stages of fermentation, whereas the predominant species in the WGS kimchi group was L. rapi at the optimal-ripening stage, and both L. sakei and L. rapi at the over-ripening stage. Significant correlations were observed by analysis of the Spearman's rank between and within the chemical and microbial composition over fermentation durations. Altogether, gizzard shad supplementation may be used to optimize the desired microbial population to obtain the preferable fresh kimchi flavour by the release of certain inorganic elements and amino N.
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Suplementos Nutricionais , Fermentação , Alimentos Fermentados/análise , Alimentos Fermentados/microbiologia , Peixes , Raphanus , Alimentos Marinhos , Animais , Cálcio/análise , Microbiologia de Alimentos/métodos , Concentração de Íons de Hidrogênio , Latilactobacillus sakei/fisiologia , Leuconostoc/fisiologia , Nitrogênio/análise , Fósforo/análiseRESUMO
Two thermophilic 1,4-α-glucan branching enzymes (GBEs), CbGBE from Caldicellulosiruptor bescii and PhGBE from Pyrococcus horikoshii, which belong to the glycoside hydrolase family 13 and 57 respectively, were cloned and expressed in Escherichia coli. Two GBEs were identified to have α-1,6 branching activity against various substrates, but substrate specificity was distinct. Starch was modified by two GBEs and their in vitro digestibility and structural properties were investigated. Short-branched A chains with a degree of polymerization (DP) of 6-12 increased with CbGBE-modified starch, increasing the proportion of slow digestible and resistant starch (RS) fractions. PhGBE-modified starch resulted in an increase in the RS fraction only by a slight increase in part of A chains (DP, 6-9). Compared to the proportion of control not treated with GBE, the proportion of α-1,6 linkages in CbGBE- and PhGBE-modified starch increased by 3.1 and 1.6 times. 13C cross polarization/magic angle sample spinning (CP/MAS) NMR and XRD pattern analysis described that GBE-modified starches reconstructed double helices but not the crystalline structure. Taken together, CbGBE and PhGBE showed distinct branching activities, resulting in different α-1,6 branching ratios and chain length distribution, and double helices amount of starch, ultimately affecting starch digestibility. Therefore, these GBEs can be used to produce customized starches with controlled digestion rates.
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Non-alcoholic fatty liver disease (NAFLD) is one of the most common liver disorders. Possible links have been recently found between the gut-microbiota and the host metabolism in development of NAFLD and obesity. Therefore, understanding the changes in intestinal microbiota during the progression of NAFLD, is important. In this study, the effect of Kombucha tea (KT), obtained by microbial fermentation of sugared black tea, was investigated on gut-microbiota during the progression of NAFLD. The results indicated a decrease in Erysipelotrichia class by treatment with KT in comparison to the methionine/choline-deficient (MCD)-fed db/db mice. Allobaculum, Turicibacter, and Clostridium genera, were only detected in MCD-fed db/db mice and were decreased after treatment with KT, whereas Lactobacillus was more abundant in MCD + KT-fed mice than in MCD only-fed mice and Mucispirillum, was found only in the MCD + KT-fed mice group. Our results demonstrated that the change of intestinal microbiota was influenced by KT intake, contributing to combat NAFLD.
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A large body of evidence suggests that B-cell lymphomas with enhanced Myc expression are associated with an aggressive phenotype and poor prognosis, which makes Myc a compelling therapeutic target. Phosphodiesterase 4B (PDE4B), a main hydrolyzer of cyclic AMP (cAMP) in B cells, was shown to be involved in cell survival and drug resistance in diffuse large B cell lymphomas (DLBCL). However, the interrelationship between Myc and PDE4B remains unclear. Here, we first demonstrate the presence of the Myc-PDE4B feed-forward loop, in which Myc and PDE4B mutually reinforce the expression of each other. Next, the combined targeting of Myc and PDE4 synergistically prevented the proliferation and survival of B lymphoma cells in vitro and in a mouse xenograft model. We finally recapitulated this combinatorial effect in Eµ-myc transgenic mice; co-inhibition of Myc and PDE4 suppressed lymphomagenesis and restored B cell development to the wild type level that was associated with marked reduction in Myc levels, unveiling the critical role of the Myc-PDE4B amplification loop in the regulation of Myc expression and the pathogenesis of B cell lymphoma. These findings suggest that the disruption of the Myc-PDE4B circuitry can be exploited in the treatment of B cell malignancies.
Assuntos
Nucleotídeo Cíclico Fosfodiesterase do Tipo 4/genética , Regulação Neoplásica da Expressão Gênica , Linfoma de Células B/genética , Linfoma de Células B/mortalidade , Proteínas Proto-Oncogênicas c-myc/genética , Animais , Biomarcadores Tumorais , Linhagem Celular Tumoral , AMP Cíclico/metabolismo , Nucleotídeo Cíclico Fosfodiesterase do Tipo 4/metabolismo , Modelos Animais de Doenças , Humanos , Imuno-Histoquímica , Linfoma de Células B/metabolismo , Linfoma de Células B/patologia , Linfoma Difuso de Grandes Células B/genética , Linfoma Difuso de Grandes Células B/metabolismo , Linfoma Difuso de Grandes Células B/mortalidade , Linfoma Difuso de Grandes Células B/patologia , Camundongos Transgênicos , Prognóstico , Ligação Proteica , Proteínas Proto-Oncogênicas c-myc/metabolismoRESUMO
Type VI secretion system (T6SS) has been discovered in a variety of gram-negative bacteria as a versatile weapon to stimulate the killing of eukaryotic cells or prokaryotic competitors. Type VI secretion effectors (T6SEs) are well known as key virulence factors for important pathogenic bacteria. In many Burkholderia species, T6SS has evolved as the most complicated secretion pathway with distinguished types to translocate diverse T6SEs, suggesting their essential roles in this genus. Here we attempted to detect and characterize T6SSs and potential T6SEs in target genomes of plant-associated and environmental Burkholderia species based on computational analyses. In total, 66 potential functional T6SS clusters were found in 30 target Burkholderia bacterial genomes, of which 33% possess three or four clusters. The core proteins in each cluster were specified and phylogenetic trees of three components (i.e., TssC, TssD, TssL) were constructed to elucidate the relationship among the identified T6SS clusters. Next, we identified 322 potential T6SEs in the target genomes based on homology searches and explored the important domains conserved in effector candidates. In addition, using the screening approach based on the profile hidden Markov model (pHMM) of T6SEs that possess markers for type VI effectors (MIX motif) (MIX T6SEs), 57 revealed proteins that were not included in training datasets were recognized as novel MIX T6SE candidates from the Burkholderia species. This approach could be useful to identify potential T6SEs from other bacterial genomes.
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Sulfolobus species can grow on a variety of organic compounds as carbon and energy sources. These species degrade glucose to pyruvate by the modified branched Entner-Doudoroff pathway. We attempted to determine the differentially expressed genes (DEGs) under sugar-limited and sugar-rich conditions. RNA sequencing (RNA-seq) was used to quantify the expression of the genes and identify those DEGs between the S. acidocaldarius cells grown under sugar-rich (YT with glucose) and sugar-limited (YT only) conditions. The functions and pathways of the DEGs were examined using gene ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analyses. Quantitative real-time PCR (qRT-PCR) was performed to validate the DEGs. Transcriptome analysis of the DSM 639 strain grown on sugar-limited and sugar-rich media revealed that 853 genes were differentially expressed, among which 481 were upregulated and 372 were downregulated under the glucose-supplemented condition. In particular, 70 genes showed significant changes in expression levels of ≥ twofold. GO and KEGG enrichment analyses revealed that the genes encoding components of central carbon metabolism, the respiratory chain, and protein and amino acid biosynthetic machinery were upregulated under the glucose condition. RNA-seq and qRT-PCR analyses indicated that the sulfur assimilation genes (Saci_2197-2204) including phosphoadenosine phosphosulfate reductase and sulfite reductase were significantly upregulated in the presence of glucose. The present study revealed metabolic networks in S. acidocaldarius that are induced in a glucose-dependent manner, improving our understanding of biomass production under sugar-rich conditions.