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1.
PLoS Genet ; 16(8): e1008783, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32813693

RESUMO

Pseudomonas aeruginosa and Candida albicans are opportunistic pathogens whose interactions involve the secreted products ethanol and phenazines. Here, we describe the role of ethanol in mixed-species co-cultures by dual-seq analyses. P. aeruginosa and C. albicans transcriptomes were assessed after growth in mono-culture or co-culture with either ethanol-producing C. albicans or a C. albicans mutant lacking the primary ethanol dehydrogenase, Adh1. Analysis of the RNA-Seq data using KEGG pathway enrichment and eADAGE methods revealed several P. aeruginosa responses to C. albicans-produced ethanol including the induction of a non-canonical low-phosphate response regulated by PhoB. C. albicans wild type, but not C. albicans adh1Δ/Δ, induces P. aeruginosa production of 5-methyl-phenazine-1-carboxylic acid (5-MPCA), which forms a red derivative within fungal cells and exhibits antifungal activity. Here, we show that C. albicans adh1Δ/Δ no longer activates P. aeruginosa PhoB and PhoB-regulated phosphatase activity, that exogenous ethanol complements this defect, and that ethanol is sufficient to activate PhoB in single-species P. aeruginosa cultures at permissive phosphate levels. The intersection of ethanol and phosphate in co-culture is inversely reflected in C. albicans; C. albicans adh1Δ/Δ had increased expression of genes regulated by Pho4, the C. albicans transcription factor that responds to low phosphate, and Pho4-dependent phosphatase activity. Together, these results show that C. albicans-produced ethanol stimulates P. aeruginosa PhoB activity and 5-MPCA-mediated antagonism, and that both responses are dependent on local phosphate concentrations. Further, our data suggest that phosphate scavenging by one species improves phosphate access for the other, thus highlighting the complex dynamics at play in microbial communities.


Assuntos
Antibiose , Candida albicans/fisiologia , Etanol/metabolismo , Fosfatos/metabolismo , Pseudomonas aeruginosa/fisiologia , Álcool Desidrogenase/genética , Álcool Desidrogenase/metabolismo , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Pseudomonas aeruginosa/metabolismo , Transdução de Sinais , Transcriptoma
2.
Nat Commun ; 11(1): 3803, 2020 07 30.
Artigo em Inglês | MEDLINE | ID: mdl-32732991

RESUMO

Microbial communities comprised of phototrophs and heterotrophs hold great promise for sustainable biotechnology. Successful application of these communities relies on the selection of appropriate partners. Here we construct four community metabolic models to guide strain selection, pairing phototrophic, sucrose-secreting Synechococcus elongatus with heterotrophic Escherichia coli K-12, Escherichia coli W, Yarrowia lipolytica, or Bacillus subtilis. Model simulations reveae metabolic exchanges that sustain the heterotrophs in minimal media devoid of any organic carbon source, pointing to S. elongatus-E. coli K-12 as the most active community. Experimental validation of flux predictions for this pair confirms metabolic interactions and potential production capabilities. Synthetic communities bypass member-specific metabolic bottlenecks (e.g. histidine- and transport-related reactions) and compensate for lethal genetic traits, achieving up to 27% recovery from lethal knockouts. The study provides a robust modelling framework for the rational design of synthetic communities with optimized growth sustainability using phototrophic partners.


Assuntos
Bacillus subtilis/metabolismo , Escherichia coli/metabolismo , Processos Heterotróficos/fisiologia , Processos Fototróficos/fisiologia , Synechococcus/metabolismo , Yarrowia/metabolismo , Aldeídos/metabolismo , Bacillus subtilis/genética , Reatores Biológicos/microbiologia , Escherichia coli/genética , Etanol/metabolismo , Formaldeído/metabolismo , Metanol/metabolismo , Microbiota/fisiologia , Modelos Biológicos , Ácido Succínico/metabolismo , Synechococcus/genética , Yarrowia/genética
3.
Int J Food Microbiol ; 333: 108796, 2020 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-32771820

RESUMO

The objective of this study was to investigate the role of yeasts in the wet fermentation of coffee beans and their contribution to coffee quality using a novel approach. Natamycin (300 ppm) was added to the fermentation mass to suppress yeast growth and their metabolic activities, and the resultant microbial ecology, bean chemistry and sensory quality were analyzed and compared to non-treated spontaneous fermentation we reported previously. The yeast community was dominated by Hanseniaspora uvarum and Pichia kudriavzevii and grew to a maximum population of about 5.5 log CFU/g in the absence of Natamycin, while when Natamycin was added yeasts were suppressed. The major bacterial species in both the spontaneous and yeast-suppressed fermentations included the lactic acid bacteria Leuconostoc mesenteroides and Lactococcus lactis, the acetic acid bacteria Gluconobacter cerinus and Acetobacter persici and the Enterobacteriaceae Enterobacter, Citrobacter and Erwinia. For both fermentations, the mucilage layers were completely degraded by the end of the process and the absence of yeast activities had no significant impact on mucilage degradation. During fermentation, reducing sugars were consumed while lactic acid was accumulated inside the beans, and its concentration was significantly higher in the spontaneous fermentation (3 times) than that where yeasts were suppressed by Natamycin. Glycerol was detected with a concentration of 0.08% in the absence of Natamycin and was not identified when Natamycin was added. Green beans fermented with yeast growth contained a higher amount of isoamyl alcohol (21 times), ethanol (3.7 times), acetaldehyde (8 times), and ethyl acetate (25 times) compared to beans fermented in the absence of yeast activities, which remained higher in the former after roasting. Beans fermented without yeast activities had a mild fruity aroma, and lower sensory scores of fragrances (7.0), flavor (6.5), acidity (6.3), body (7.0) and overall score (6.5) compared to the former. These findings demonstrated the crucial roles of yeasts in wet fermentation of coffee beans and for producing high quality coffee.


Assuntos
Bactérias/metabolismo , Café/metabolismo , Fermentação/fisiologia , Hanseniaspora/metabolismo , Pichia/metabolismo , Leveduras/metabolismo , Acetaldeído/metabolismo , Acetatos/metabolismo , Ácido Acético/metabolismo , Anti-Infecciosos/farmacologia , Bactérias/classificação , Reatores Biológicos/microbiologia , Café/microbiologia , Etanol/metabolismo , Ácido Láctico/metabolismo , Natamicina/farmacologia , Odorantes/análise , Pentanóis/metabolismo , Paladar
4.
Chemosphere ; 258: 127320, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32554008

RESUMO

Microorganisms play important roles in the degradation of volatile organic compounds. Aeromonas salmonicida strain (AEP-3) generated from biomass in the citric acid fermentation industry was screened and subjected to denaturing gradient gel electrophoresis (DGGE) fingerprinting and 16S rDNA gene sequencing. The growth conditions of AEP-3 in Luria-Bertani broth were optimized at 25 °C and approximately pH 7. AEP-3 was used to degrade ethyl formate, propionic aldehyde, or acetone alone and their mixture. The concentrations of ethyl formate, propionic aldehyde, and acetone were below 7500, 600, and 800 mg L-1, respectively, and their maximum degradation efficiencies were 100%, 92.41%, and 34.75%. AEP-3 first degraded acetone and propionic aldehyde in the mixture, followed by ethyl formate. The degradation pathways of these organic compounds in the mixture and their substrate interactions during degradation were explored. Propionic aldehyde was first converted into propionic acid in the metabolic process and was involved in the subsequent carboxylic acid cycle. By contrast, ethyl formate was first hydrolyzed into formic acid and ethanol. Then, formic acid participated in the cyclic metabolism of carboxylic acid, whereas, ethanol was hydrolyzed into acetaldehyde and acetic acid through alcohol and aldehyde dehydrogenase. Additionally, acetone directly interacted with nitrate in the medium under the action of hydrogen ions and produced carbon dioxide, water, and nitrogen. Overall, this study provides a new degrading bacterium biodegradability toward the exhaust gas of citric acid fermentation.


Assuntos
Acetona/metabolismo , Aeromonas salmonicida/metabolismo , Ésteres do Ácido Fórmico/metabolismo , Acetaldeído , Ácido Acético/metabolismo , Biodegradação Ambiental , Biomassa , Ácido Cítrico/metabolismo , Etanol/metabolismo , Fermentação , Formiatos , Propionatos/metabolismo
5.
Int J Food Microbiol ; 329: 108651, 2020 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-32512285

RESUMO

In Latin, 'pulcherrima' is a superlative form of an adjective that translates as beautiful. Apart from being 'the most beautiful' yeast, Metschnikowia pulcherrima has a remarkable potential in production of wines with lower ethanol content. The oenological performance of six M. pulcherrima strains was hereby tested in sequential cultures with Saccharomyces cerevisiae. The best-performing strain MP2 was further characterised in fermentations with different S. cerevisiae inoculation delays in both white grape juice and Chemically Defined Grape Juice Medium (CDGJM). The analysis of main metabolites, undertaken prior to sequential inoculations and upon fermentation completion, highlighted metabolic interactions and carbon sinks other than ethanol in MP2 treatments. Depending on the inoculation delay, MP2 white wines contained between 0.6% and 1.2% (v/v) less ethanol than the S. cerevisiae monoculture, with even larger decreases detected in the CDGJM. The MP2 treatments also contained higher concentrations of TCA cycle by-products (i.e. fumarate and succinate) and glycerol, and lower concentrations of acetic acid. The analysis of volatile compounds showed increased production of acetate esters and higher alcohols in all MP2 wines, alongside other compositional alterations arising from the S. cerevisiae inoculation delay.


Assuntos
Fermentação , Microbiologia de Alimentos/métodos , Metschnikowia/metabolismo , Saccharomyces cerevisiae/metabolismo , Vinho/microbiologia , Ácido Acético/metabolismo , Etanol/metabolismo , Glicerol/metabolismo , Fatores de Tempo , Vitis/metabolismo , Vitis/microbiologia , Vinho/análise
6.
Mol Pharmacol ; 98(2): 120-129, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32499331

RESUMO

Alcohol dehydrogenases (ADHs) and aldehyde dehydrogenases (ALDHs) are vital enzymes involved in the metabolism of a variety of alcohols. Differences in the expression and enzymatic activity of human ADHs and ALDHs correlate with individual variability in metabolizing alcohols and drugs and in the susceptibility to alcoholic liver disease. MicroRNAs (miRNAs) function as epigenetic modulators to regulate the expression of drug-metabolizing enzymes. To characterize miRNAs that target ADHs and ALDHs in human liver cells, we carried out a systematic bioinformatics analysis to analyze free energies of the interaction between miRNAs and their cognate sequences in ADH and ALDH transcripts and then calculated expression correlations between miRNAs and their targeting ADH and ALDH genes using a public data base. Candidate miRNAs were selected to evaluate bioinformatic predictions using a series of biochemical assays. Our results showed that 11 miRNAs have the potential to modulate the expression of two ADH and seven ALDH genes in the human liver. We found that hsa-miR-1301-3p suppressed the expression of ADH6, ALDH5A1, and ALDH8A1 in liver cells and blocked their induction by ethanol. In summary, our results revealed that hsa-miR-1301-3p plays an important role in ethanol metabolism by regulating ADH and ALDH gene expression. SIGNIFICANCE STATEMENT: Systematic bioinformatics analysis showed that 11 microRNAs might play regulatory roles in the expression of two alcohol dehydrogenase (ADH) and seven aldehyde dehydrogenase (ALDH) genes in the human liver. Experimental evidences proved that hsa-miR-1301-3p suppressed the expression of ADH6, ALDH5A1, and ALDH8A1 in liver cells and decreased their inducibility by ethanol.


Assuntos
Álcool Desidrogenase/genética , Aldeído Desidrogenase/genética , Fígado/metabolismo , MicroRNAs/genética , Succinato-Semialdeído Desidrogenase/genética , Acetaldeído/metabolismo , Acetatos/metabolismo , Linhagem Celular , Etanol/metabolismo , Regulação da Expressão Gênica , Células HEK293 , Células Hep G2 , Humanos , Redes e Vias Metabólicas
7.
Artigo em Inglês | MEDLINE | ID: mdl-32560357

RESUMO

Assessments in blood and saliva suggests that the amount of ethanol present in the first hours after alcohol consumption and into the following morning is associated with hangover severity. The current analysis determines how ethanol elimination rate is related to hangover severity reported throughout the day. n = 8 subjects participated in two studies. The first was a naturalistic study comprising an evening of alcohol consumption. Hangover severity was assessed hourly from 10 a.m. to 4 p.m., using a 1-item hangover severity scale ranging from 0 (absent) to 10 (extreme). The second study comprised a highly controlled alcohol challenge to reach a breath alcohol concentration (BrAC) of 0.05%. Breathalyzer tests were conducted every 5 min until BrAC reached zero. The ethanol elimination rate, expressed in BrAC%/hour, was computed by dividing the peak BrAC (%) by the time to BrAC of zero (h). At 11:00, 13:00, and 14:00, there were significant negative partial correlations, controlling for estimated BrAC, between ethanol elimination rate and hangover severity. The findings suggest that drinkers with a faster ethanol elimination rate experience less severe hangovers. The observations should be confirmed in a larger sample of subjects who participate in a single study that assesses both hangover severity and ethanol elimination rate.


Assuntos
Intoxicação Alcoólica , Etanol , Consumo de Bebidas Alcoólicas , Intoxicação Alcoólica/complicações , Testes Respiratórios , Etanol/metabolismo , Humanos , Adulto Jovem
8.
Arch Microbiol ; 202(7): 1889-1898, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32448963

RESUMO

Alcohol consumption exacerbates the pathogenesis of hepatitis C virus (HCV) infection and aggravates disease consequences in alcohol-abusing patients. Although the exact reasons by which alcohol consumption affects several cellular pathways in liver cells are not clear, they might be partially attributed to the ability of alcohol to further suppress the innate immunity, modulation of autophagy and also its relationship with reactive oxygen species (ROS) generation. To evaluate these issues, Huh7 cells harboring HCV replicon and Cytochrome p450 (CYP2E1) plasmid were exposed to ethanol and mRNA expression of Beclin-1, interferon-stimulated gene15 (ISG15) genes and HCV NS5B for two different times were relatively quantitated. ROS was determined by flow cytometry. The results showed that alcohol treatment in a short time caused an increase in HCV NS5B and Beclin-1 mRNA and decreased ISG 15 mRNA. Long-lasting alcohol treatment increased ROS production in Huh-7 cells and HCV replication was reduced. In conclusion, acute alcohol treatment might contribute to increase HCV replication by interference in innate immunity and induction of autophagy. Chronic alcohol treatment caused oxidative stress, which disrupts autophagy and thereby increased the rate of Huh7 cell injury.


Assuntos
Etanol/toxicidade , Hepacivirus/fisiologia , Hepatite C/virologia , Estresse Oxidativo/efeitos dos fármacos , Replicação Viral/efeitos dos fármacos , Autofagia , Linhagem Celular Tumoral , Etanol/metabolismo , Hepatite C/imunologia , Humanos , Imunidade Inata
9.
Nat Commun ; 11(1): 2555, 2020 05 22.
Artigo em Inglês | MEDLINE | ID: mdl-32444624

RESUMO

Fetal alcohol exposure (FAE) is the leading preventable developmental cause of cognitive dysfunction. Even in the absence of binge drinking, alcohol consumption during pregnancy can leave offspring deficient. However, the mechanisms underlying these deficiencies are unknown. Using a mouse model of gestational ethanol exposure (GEE), we show increased instrumental lever-pressing and disruption of efficient habitual actions in adults, indicative of disrupted cognitive function. In vivo electrophysiology reveals disrupted action encoding in dorsolateral striatum (DLS) associated with altered habit learning. GEE mice exhibit decreased GABAergic transmission onto DLS projection neurons, including inputs from parvalbumin interneurons, and increased endocannabinoid tone. Chemogenetic activation of DLS parvalbumin interneurons reduces the elevated lever pressing of GEE mice. Pharmacologically increasing endocannabinoid tone mimics GEE effects on cognition and synaptic transmission. These findings show GEE induces long-lasting deficits in cognitive function that may contribute to human FAE, and identify potential mechanisms for future therapeutic targeting.


Assuntos
Corpo Estriado/fisiopatologia , Etanol/efeitos adversos , Exposição Materna/efeitos adversos , Efeitos Tardios da Exposição Pré-Natal/psicologia , Animais , Cognição/efeitos dos fármacos , Corpo Estriado/metabolismo , Corpo Estriado/fisiologia , Etanol/metabolismo , Feminino , Desenvolvimento Fetal , Humanos , Masculino , Camundongos Endogâmicos C57BL , Linhagem , Gravidez , Efeitos Tardios da Exposição Pré-Natal/etiologia , Efeitos Tardios da Exposição Pré-Natal/fisiopatologia
11.
Traffic Inj Prev ; 21(5): 295-297, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32255712

RESUMO

Objective: Auto-Brewery Syndrome is defined as the production of ethanol by microorganisms becoming dominant when inhabiting the gastrointestinal system or through the impairment of flora because of carbohydrate-rich nutrition, and the elevation of levels of measured ethanol. This study aimed to consider medicolegal approaches to individuals with Auto-Brewery Syndrome.Methods: A 38-year-old male patient who was involved in a traffic accident about two months ago and whose driving license was taken away due to his blood alcohol level measuring above the legal limits was referred to our department for the detection of any condition which might cause the elevation of blood alcohol levels without alcohol intake, in consequence of his objection submitted to the judicial authorities claiming that he had not drunk alcohol on the day of the event.Results: After the informed consent of the individual was obtained, he was admitted under supervision to an inpatient unit with a visitor ban in a manner which inhibited his intake of alcohol, and during admission his blood alcohol levels were measured at intervals. His blood alcohol level was measured as 160 mg/dl at the time of admission for monitoring and as 141 mg/dl, 322 mg/dl, 208 mg/dl and 279 mg/dl after two hours, six hours, 12 hours and 20 hours, respectively. His liver function test results were high and neurological examination was normal. The individual was diagnosed with Auto-Brewery Syndrome.Conclusion: Various gastrointestinal system abnormalities such as through laparotomy, gastrectomy are reported in most of Auto-Brewery syndrome cases. There are cases, although rare, where gastrointestinal disorders are not detected and secondary disorders of normal intestinal flora due to frequent antibiotic use seem to be a factor. Such a condition is present in the current case. Those who are aware of this condition may falsely rely on it as a method to avoid penalties. On the other hand, genuine patients suffering from this condition may be caught by traffic control and become victims of the condition. For that reason, a meticulous and planned approach should be taken to verify the condition and to ensure that it is not overlooked.


Assuntos
Acidentes de Trânsito/legislação & jurisprudência , Intoxicação Alcoólica/diagnóstico , Condução de Veículo/legislação & jurisprudência , Concentração Alcoólica no Sangue , Adulto , Intoxicação Alcoólica/metabolismo , Etanol/metabolismo , Fermentação , Humanos , Masculino , Síndrome
12.
World J Microbiol Biotechnol ; 36(4): 59, 2020 Mar 31.
Artigo em Inglês | MEDLINE | ID: mdl-32236784

RESUMO

An endogenous homoethanol pathway (glucose/1.2 xylose => 2 pyruvate => 2 ethanol) was previously engineered in Escherichia coli SZ410 via eliminating acid-producing pathways and anaerobic expression of the pyruvate dehydrogenase complex (aceEF-lpd operon). This ethanologenic derivative was subsequently engineered through adaptive evolution and partial deletion of the RNase G, resulting in an improved strain of E. coli RM10 for ethanol production using C6 and C5 sugars. Nevertheless, compared to the ethanol tolerance and/or ethanol titer achieved by industrial yeast, further incremental improvement of RM10 was needed for ethanol production using cellulosic biomass derived C6 and C5 sugars. In this study, the role of aldB gene (encoding for acetaldehyde dehydrogenase, AldB, which oxidizes acetaldehyde to acetic acid) was evaluated for ethanol/acetaldehyde tolerance and xylose fermentation by RM10. Deletion of aldB gene decreased ethanol tolerance, fermentative cell growth and ethanol production from xylose; while overexpression of aldB gene improved fermentative cell growth, and increased ethanol production from xylose. The improvement is likely attributed to preventing acetaldehyde accumulation (a toxic intermediate of homoethanol pathway) via AldB catalyzed oxidation.


Assuntos
Aldeído Oxirredutases/metabolismo , Escherichia coli/crescimento & desenvolvimento , Etanol/metabolismo , Xilose/metabolismo , Aldeído Oxirredutases/genética , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Endorribonucleases/genética , Escherichia coli/genética , Escherichia coli/metabolismo , Proteínas de Escherichia coli/genética , Proteínas de Escherichia coli/metabolismo , Fermentação , Deleção de Genes
13.
Food Chem ; 321: 126691, 2020 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-32251922

RESUMO

Low-alcohol Huangjiu (LAH), which contains reduced contents of ethanol and higher alcohols, is prepared by diluting original Huangjiu that has a high ethanol content, which leads to a weakened flavor (i.e., acidity). To increase acidity and reduce higher alcohols level in LAH, the gene ALD6 encoding aldehyde dehydrogenase was expressed in yeast HJ-1 under the control of the pPGK1 promoter and terminators with varying activities (tGIC1, tPGK1 and tCPS1) by scarless replacement at BAT2 locus, yielding the engineered strains HJΔB-AG, HJΔB-AP, and HJΔB-AC. The acetate concentration produced by HJΔB-AG, HJΔB-AP, and HJΔB-AC was 1.26-, 1.84-, and 2.51-fold of that of HJ-1, respectively. Furthermore, the concentration of higher alcohols produced by HJΔB-AG, HJΔB-AP, and HJΔB-AC decreased by 39.91%, 45.55%, and 52.80%, respectively. This study resulted in the creation of promising recombinant yeast strains and introduced a method that can be used for the high-quality production of LAH by acid-producing Saccharomyces cerevisiae.


Assuntos
Etanol/metabolismo , Microrganismos Geneticamente Modificados , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Vinho/microbiologia , Acetatos/metabolismo , Álcoois , Aldeído Oxirredutases/genética , Aldeído Oxirredutases/metabolismo , Fermentação , Microbiologia de Alimentos , Regiões Promotoras Genéticas , Proteínas de Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/metabolismo , Regiões Terminadoras Genéticas , Transaminases/genética , Transaminases/metabolismo
14.
Arch Microbiol ; 202(7): 1729-1739, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32328754

RESUMO

We isolated two Candida pseudointermedia strains from the Atlantic rain forest in Brazil, and analyzed cellobiose metabolization in their cells. After growth in cellobiose medium, both strains had high intracellular ß-glucosidase activity [~ 200 U (g cells)-1 for 200 mM cellobiose and ~ 100 U (g cells)-1 for 2 mM pNPßG] and negligible periplasmic cellobiase activity. During batch fermentation, the strain with the best performance consumed all the available cellobiose in the first 18 h of the assay, producing 2.7 g L-1 of ethanol. Kinetics of its cellobiase activity demonstrated a high-affinity hydrolytic system inside cells, with Km of 12.4 mM. Our data suggest that, unlike other fungal species that hydrolyze cellobiose extracellularly, both analyzed strains transport it to the cytoplasm, where it is then hydrolyzed by high-affinity intracellular ß-glucosidases. We believe this study increases the fund of knowledge regarding yeasts from Brazilian microbiomes.


Assuntos
Candida/enzimologia , Celobiose/metabolismo , Madeira/metabolismo , Madeira/microbiologia , beta-Glucosidase/metabolismo , Brasil , Candida/isolamento & purificação , Candida/metabolismo , Metabolismo dos Carboidratos , Etanol/metabolismo , Fermentação , Hidrólise , Cinética
15.
Nat Commun ; 11(1): 1937, 2020 04 22.
Artigo em Inglês | MEDLINE | ID: mdl-32321909

RESUMO

The fiber in corn kernels, currently unutilized in the corn to ethanol process, represents an opportunity for introduction of cellulose conversion technology. We report here that Clostridium thermocellum can solubilize over 90% of the carbohydrate in autoclaved corn fiber, including its hemicellulose component glucuronoarabinoxylan (GAX). However, Thermoanaerobacterium thermosaccharolyticum or several other described hemicellulose-fermenting thermophilic bacteria can only partially utilize this GAX. We describe the isolation of a previously undescribed organism, Herbinix spp. strain LL1355, from a thermophilic microbiome that can consume 85% of the recalcitrant GAX. We sequence its genome, and based on structural analysis of the GAX, identify six enzymes that hydrolyze GAX linkages. Combinations of up to four enzymes are successfully expressed in T. thermosaccharolyticum. Supplementation with these enzymes allows T. thermosaccharolyticum to consume 78% of the GAX compared to 53% by the parent strain and increases ethanol yield from corn fiber by 24%.


Assuntos
Clostridiales/metabolismo , Técnicas de Cocultura/métodos , Etanol/metabolismo , Microbiologia Industrial/métodos , Thermoanaerobacterium/metabolismo , Zea mays/microbiologia , Celulose/metabolismo , Clostridiales/genética , Fermentação , Temperatura Alta , Thermoanaerobacterium/genética , Xilanos/metabolismo , Zea mays/metabolismo
16.
Xenobiotica ; 50(10): 1180-1201, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32338108

RESUMO

Ethanol, as a small-molecule organic compound exhibiting both hydrophilic and lipophilic properties, quickly pass through the biological barriers. Over 95% of absorbed ethanol undergoes biotransformation, the remaining amount is excreted unchanged, mainly with urine and exhaled air.The main route of ethyl alcohol metabolism is its oxidation to acetaldehyde, which is converted into acetic acid with the participation of cytosolic NAD+ - dependent alcohol (ADH) and aldehyde (ALDH) dehydrogenases. Oxidative biotransformation pathways of ethanol also include reactions catalyzed by the microsomal ethanol oxidizing system (MEOS), peroxisomal catalase and aldehyde (AOX) and xanthine (XOR) oxidases. The resulting acetic acid can be activated to acetyl-CoA by the acetyl-CoA synthetase (ACS).It is also possible, to a much smaller extent, non-oxidative routes of ethanol biotransformation including its esterification with fatty acids by ethyl fatty acid synthase (FAEES), re-esterification of phospholipids, especially phosphatidylcholines, with phospholipase D (PLD), coupling with sulfuric acid by alcohol sulfotransferase (SULT) and with glucuronic acid using UDP-glucuronyl transferase (UGT, syn. UDPGT).The intestinal microbiome plays a significant role in the ethanol biotransformation and in the initiation and progression of liver diseases stimulated by ethanol and its metabolite - acetaldehyde, or by lipopolysaccharide and ROS.


Assuntos
Biotransformação/fisiologia , Etanol/metabolismo , Acetaldeído , Catalase/metabolismo , Humanos , Taxa de Depuração Metabólica , Redes e Vias Metabólicas , Microssomos Hepáticos/metabolismo , Oxirredução
17.
Braz J Med Biol Res ; 53(4): e9200, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32267309

RESUMO

The consumption of alcoholic beverages influences carbohydrate and lipid metabolism, although it is not yet clear whether metabolism during physical exercise at different intensities is also affected. This was the objective of the present study. Eight young and healthy volunteers performed a treadmill test to identify the running speed corresponding to a lactate concentration of 4 mM (S4mM). At least 48 h later, they were subjected to two experimental trials (non-alcohol or alcohol) in which they performed two 1-km running sessions at the following intensities: 1) S4mM; 2) 15% above S4mM. In both trials, blood lactate, triglycerides, and glucose concentrations were measured before and after exercise. The acute alcohol intake increased triglycerides, but not lactate concentration under resting conditions. Interestingly, alcohol intake enhanced the exercise-induced increase in lactate concentration at the two intensities: S4mM (non-alcohol: 4.2±0.3 mM vs alcohol: 4.8±0.9 mM; P=0.003) and 15% above S4mM trial (P=0.004). When volunteers ingested alcohol, triglycerides concentration remained increased after treadmill running (e.g., at S4mM - at rest; non-alcohol: 0.2±0.5 mM vs alcohol: 1.3±1.3 mM; P=0.048). In contrast, glucose concentration was not modified by either alcohol intake, exercise, or their combination. We concluded that an acute alcohol intake changed lactate and lipid metabolism without affecting blood glucose concentration. In addition, the increase in lactate concentration caused by alcohol was specifically observed when individuals exercised, whereas augmented triglycerides concentration was already observed before exercise and was sustained thereafter.


Assuntos
Consumo de Bebidas Alcoólicas/sangue , Bebidas Alcoólicas/análise , Glicemia/metabolismo , Etanol/metabolismo , Ácido Láctico/sangue , Resistência Física/efeitos dos fármacos , Adulto , Desempenho Atlético/fisiologia , Glicemia/análise , Teste de Esforço , Humanos , Masculino , Resistência Física/fisiologia , Triglicerídeos/sangue , Adulto Jovem
18.
Nat Commun ; 11(1): 1998, 2020 04 24.
Artigo em Inglês | MEDLINE | ID: mdl-32332730

RESUMO

Alcohol consumption is a consistent protective factor for the development of autoimmune diseases such as rheumatoid arthritis (RA). The underlying mechanism for this tolerance-inducing effect of alcohol, however, is unknown. Here we show that alcohol and its metabolite acetate alter the functional state of T follicular helper (TFH) cells in vitro and in vivo, thereby exerting immune regulatory and tolerance-inducing properties. Alcohol-exposed mice have reduced Bcl6 and PD-1 expression as well as IL-21 production by TFH cells, preventing proper spatial organization of TFH cells to form TFH:B cell conjugates in germinal centers. This effect is associated with impaired autoantibody formation, and mitigates experimental autoimmune arthritis. By contrast, T cell independent immune responses and passive models of arthritis are not affected by alcohol exposure. These data clarify the immune regulatory and tolerance-inducing effect of alcohol consumption.


Assuntos
Consumo de Bebidas Alcoólicas/imunologia , Artrite Experimental/imunologia , Artrite Reumatoide/imunologia , Etanol/farmacologia , Linfócitos T Auxiliares-Indutores/efeitos dos fármacos , Ácido Acético/metabolismo , Ácido Acético/farmacologia , Animais , Artrite Experimental/prevenção & controle , Artrite Reumatoide/prevenção & controle , Autoanticorpos/imunologia , Autoimunidade/efeitos dos fármacos , Linfócitos B/efeitos dos fármacos , Linfócitos B/imunologia , Colágeno/administração & dosagem , Colágeno/imunologia , Etanol/metabolismo , Feminino , Humanos , Camundongos , Fatores de Proteção , Tolerância a Antígenos Próprios/efeitos dos fármacos , Linfócitos T Auxiliares-Indutores/imunologia
19.
J Food Sci ; 85(4): 1070-1081, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32125714

RESUMO

Wines produced from grapes cultivated in cool climate areas are characterized by high levels of organic acids. One method to correct this is malolactic fermentation (MLF). The aim of this study was to determine the effectiveness of different strains of Oenococcus oeni bacteria (Viniflora CH11, Viniflora CH16, Viniflora CH35, Viniflora Oenos, SIHA LACT Oeno) during the biological acidity reduction process. Red wine from Rondo and Regent cultivars was obtained by ethanol fermentation of the pulp, at 20 °C for 14 days. The profile of organic acids was examined with a particular focus on changes in the content of l-malic and l-lactic acids. Additionally, the impact on profile and quantity of phenolic compounds and antioxidant capacity was measured. The results showed that MLF had a positive influence on content of organic acids through the reduction of l-malic acid content with a simultaneous increase of the amount of l-lactic acid. The best effect was obtained with the CH11 and CH35 bacterial strains. The biological acidity reduction process had no significant (P > 0.05) impact on phenolic content or antioxidant capacity. However, the wine making process (ethanol fermentation, maturation) contributed to the reduction of polyphenols and in consequence lower antioxidant capacity of the final tested wines. PRACTICAL APPLICATION: The present study provides useful information on the impact of different Oenococcus oeni bacterial strains on MLF in red wines, reduction of l-malic to l-lactic acid, and stability of phenolic compounds during MLF and the maturation period. Also, this article provides information about phenolic compounds and antioxidant capacity during malolactic fermentation and maturity of red wines made from hybrids of Vitis vinifera such as Rondo and Regent cultivars.


Assuntos
Ácido Láctico/metabolismo , Malatos/metabolismo , Oenococcus/metabolismo , Fenóis/metabolismo , Vitis/microbiologia , Etanol/análise , Etanol/metabolismo , Fermentação , Ácido Láctico/análise , Malatos/análise , Oenococcus/classificação , Oenococcus/genética , Oenococcus/isolamento & purificação , Fenóis/análise , Vitis/química , Vinho/análise , Vinho/microbiologia
20.
Arch Biochem Biophys ; 686: 108329, 2020 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-32151565

RESUMO

In the body, alcohol dehydrogenase rapidly converts ethanol to its toxic metabolite, acetaldehyde, which is further metabolized to non-toxic acetic acid by aldehyde dehydrogenase (ALDH). 6-(methylsulfinyl)hexyl isothiocyanate (6-MSITC), a major bioactive compound in Wasabi (Wasabia japonica) has various physiological effects such as anti-oxidative, anti-inflammatory and anti-cancer effects. However, the effect of 6-MSITC on alcohol metabolism has not been studied. In this study, we investigated the effects of 6-MSITC on hepatic ALDH activity and protein expression both in vitro and in vivo. 6-MSITC inhibited ethanol- and acetaldehyde-induced cytotoxicity. Treatment with 6-MSITC to HepG2 cells enhanced ALDH activity through the induction of mitochondrial ALDH2 expression, but not cytosolic ALDH1A1. Knockdown of Nrf2 canceled the 6-MSITC-induced ALDH2 expression, indicating that Nrf2 regulated ALDH2 expression. Moreover, 6-MSITC increased the nuclear translocation of Nrf2 and the expression levels of HO-1 and SOD2, Nrf2-regulated phase II drug-metabolizing enzymes. Oral administration of 6-MSITC increased the mitochondrial ALDH2 activity and its expression in the liver of C57BL/6J mice. These results suggested that 6-MSITC is possible to protect acetaldehyde toxicity in hepatocytes by induction of mitochondrial ALDH2 expression through Nrf2/ARE pathway.


Assuntos
Acetaldeído/metabolismo , Aldeído-Desidrogenase Mitocondrial/metabolismo , Antineoplásicos/farmacologia , Hepatócitos/metabolismo , Isotiocianatos/farmacologia , Acetaldeído/toxicidade , Alanina Transaminase/metabolismo , Álcool Desidrogenase/metabolismo , Aldeído-Desidrogenase Mitocondrial/genética , Animais , Aspartato Aminotransferases/metabolismo , Etanol/metabolismo , Regulação da Expressão Gênica/efeitos dos fármacos , Técnicas de Silenciamento de Genes , Heme Oxigenase-1/metabolismo , Células Hep G2 , Humanos , Fígado/metabolismo , Masculino , Camundongos Endogâmicos C57BL , Fator 2 Relacionado a NF-E2/metabolismo , Fosforilação , Superóxido Dismutase/metabolismo
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