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Sánchez Alfonso, Andrea Catherine - One of the best experts on this subject based on the ideXlab platform.
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Selección de los marcadores cultivables y moleculares útiles para diferenciar el origen de la contaminación fecal en el Río Bogotá
Maestría en Ciencias Biológicas, 2017Co-Authors: Sánchez Alfonso, Andrea CatherineAbstract:La detección de microorganismos patógenos intestinales en el agua se dificulta debido al alto costo de las pruebas y al tiempo de análisis. Como alternativa, se utilizan microorganismos indicadores, los cuales no diferencian si la contaminación es de origen fecal humano o animal, ya que hacen parte del tracto digestivo de ambos. Para discriminar el origen de la contaminación fecal, se ha propuesto el uso de marcadores dependientes de cultivo y moleculares que pueden presentar especificidad geográfica, por lo que es necesario identificar aquellos aplicables en nuestro medio. El objetivo de este trabajo fue seleccionar los marcadores cultivables y moleculares para diferenciar el origen de la contaminación fecal en el río Bogotá. Para diferenciar la contaminación de origen porcino, se aisló una cepa a partir de contenido intestinal de porcino identificada como Bacteroides fragilis PZ8. Se evaluaron indicadores no discriminantes: coliformes totales, E. coli, colifagos somáticos y fagos que infectan la cepa de Bacteroides fragilis RYC2056, indicadores discriminantes: fagos que infectan las cepas de Bacteroides thetaiotaomicron GA17 y Bacteroides fragilis PZ8 y marcadores moleculares discriminantes: Bacteroidetes HF183F y CF128F, Bifidobacterium adolescentis (ADO) y Bifidobacterium dentium (DEN), mediante PCR, en agua residual proveniente de plantas de beneficio de ganado bovino y porcino, de Plantas de Tratamiento de Agua Residual Doméstica (PTARD) y del río Bogotá. Se evidenció que las cepas de Bacteroides GA17 y PZ8 tienen potencial para discriminar la contaminación fecal humana y de porcino respectivamente, en las aguas evaluadas. Con la relación entre colifagos somáticos y fagos que infectan la cepa GA17, de dos unidades, se evidenció que la contaminación del río Bogotá es principalmente de origen humano. Los marcadores moleculares HF183F, ADO y DEN indicaron la presencia de contaminación humana y el marcador CF128F, la presencia de contaminación bovina en las aguas evaluadas. Los resultados obtenidos permiten concluir que los marcadores seleccionados son potencialmente útiles para discriminar el origen de la contaminación fecal en el río Bogotá.The detection of intestinal pathogenic microorganisms in water is difficult due to the high cost of testing and the time of analysis. As an alternative, indicator microorganisms are used, which do not differentiate if the contamination is of human or animal fecal origin. To discriminate the origin of fecal contamination, it has been proposed the use of culture-dependent and molecular markers that may present geographic specificity, so it is necessary to identify those applicable in our environment. The objective of this work was to select the cultivable and molecular markers to differentiate the origin of the fecal contamination in the Bogotá river. For this a strain was isolated from porcine intestinal contents identified as Bacteroides fragilis PZ8. Non-discriminatory indicators as: total coliforms, E. coli, somatic coliphages and Bacteroides fragilis phages strain RYC2056, discriminant indicators: Bacteroides thetaiotaomicron strain GA17 and Bacteroides fragilis PZ8 phages, and molecular markers: HF183F, CF128F and Bifidobacterium adolescentis (ADO) and Bifidobacterium dentium (DEN), by PCR, in wastewater from bovine and porcine abattoir, wastewater treatment plants (WWTP) and Bogotá river. It was evidenced that strains GA17 and PZ8 have the potential to discriminate human and porcine fecal contamination, respectively, in the evaluated waters. The relationship between somatic coliphages and phage strain GA17 of two units, showed that the contamination of the Bogotá river is mainly of human origin. The molecular markers HF183F, ADO and DEN indicated the presence of human contamination and the marker CF128F, the presence of bovine contamination in the evaluated waters. The selected markers are potentially useful to discriminate the origin of fecal contamination in the Bogotá river
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Selección de los marcadores cultivables y moleculares útiles para diferenciar el origen de la contaminación fecal en el Río Bogotá
'Universidad Nacional Hermilio Valdizan - Facultad de Ciencias de la Educacion', 2017Co-Authors: Sánchez Alfonso, Andrea CatherineAbstract:La detección de microorganismos patógenos intestinales en el agua se dificulta debido al alto costo de las pruebas y al tiempo de análisis. Como alternativa, se utilizan microorganismos indicadores, los cuales no diferencian si la contaminación es de origen fecal humano o animal, ya que hacen parte del tracto digestivo de ambos. Para discriminar el origen de la contaminación fecal, se ha propuesto el uso de marcadores dependientes de cultivo y moleculares que pueden presentar especificidad geográfica, por lo que es necesario identificar aquellos aplicables en nuestro medio. El objetivo de este trabajo fue seleccionar los marcadores cultivables y moleculares para diferenciar el origen de la contaminación fecal en el río Bogotá. Para diferenciar la contaminación de origen porcino, se aisló una cepa a partir de contenido intestinal de porcino identificada como Bacteroides fragilis PZ8. Se evaluaron indicadores no discriminantes: coliformes totales, E. coli, colifagos somáticos y fagos que infectan la cepa de Bacteroides fragilis RYC2056, indicadores discriminantes: fagos que infectan las cepas de Bacteroides thetaiotaomicron GA17 y Bacteroides fragilis PZ8 y marcadores moleculares discriminantes: Bacteroidetes HF183F y CF128F, Bifidobacterium adolescentis (ADO) y Bifidobacterium dentium (DEN), mediante PCR, en agua residual proveniente de plantas de beneficio de ganado bovino y porcino, de Plantas de Tratamiento de Agua Residual Doméstica (PTARD) y del río Bogotá. Se evidenció que las cepas de Bacteroides GA17 y PZ8 tienen potencial para discriminar la contaminación fecal humana y de porcino respectivamente, en las aguas evaluadas. Con la relación entre colifagos somáticos y fagos que infectan la cepa GA17, de dos unidades, se evidenció que la contaminación del río Bogotá es principalmente de origen humano. Los marcadores moleculares HF183F, ADO y DEN indicaron la presencia de contaminación humana y el marcador CF128F, la presencia de contaminación bovina en las aguas evaluadas. Los resultados obtenidos permiten concluir que los marcadores seleccionados son potencialmente útiles para discriminar el origen de la contaminación fecal en el río Bogotá.The detection of intestinal pathogenic microorganisms in water is difficult due to the high cost of testing and the time of analysis. As an alternative, indicator microorganisms are used, which do not differentiate if the contamination is of human or animal fecal origin. To discriminate the origin of fecal contamination, it has been proposed the use of culture-dependent and molecular markers that may present geographic specificity, so it is necessary to identify those applicable in our environment. The objective of this work was to select the cultivable and molecular markers to differentiate the origin of the fecal contamination in the Bogotá river. For this a strain was isolated from porcine intestinal contents identified as Bacteroides fragilis PZ8. Non-discriminatory indicators as: total coliforms, E. coli, somatic coliphages and Bacteroides fragilis phages strain RYC2056, discriminant indicators: Bacteroides thetaiotaomicron strain GA17 and Bacteroides fragilis PZ8 phages, and molecular markers: HF183F, CF128F and Bifidobacterium adolescentis (ADO) and Bifidobacterium dentium (DEN), by PCR, in wastewater from bovine and porcine abattoir, wastewater treatment plants (WWTP) and Bogotá river. It was evidenced that strains GA17 and PZ8 have the potential to discriminate human and porcine fecal contamination, respectively, in the evaluated waters. The relationship between somatic coliphages and phage strain GA17 of two units, showed that the contamination of the Bogotá river is mainly of human origin. The molecular markers HF183F, ADO and DEN indicated the presence of human contamination and the marker CF128F, the presence of bovine contamination in the evaluated waters. The selected markers are potentially useful to discriminate the origin of fecal contamination in the Bogotá river.Magíster en Ciencias BiológicasMaestrí
Francesca Turroni - One of the best experts on this subject based on the ideXlab platform.
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decoding the genomic variability among members of the Bifidobacterium dentium species
Microorganisms, 2020Co-Authors: Gabriele Andrea Lugli, Christian Milani, Francesca Turroni, Chiara Tarracchini, Giulia Alessandri, Leonardo Mancabelli, Vera Neuzilbunesova, Lorena Ruiz, Abelardo MargollesAbstract:Members of the Bifidobacterium dentium species are usually identified in the oral cavity of humans and associated with the development of plaque and dental caries. Nevertheless, they have also been detected from fecal samples, highlighting a widespread distribution among mammals. To explore the genetic variability of this species, we isolated and sequenced the genomes of 18 different B. dentium strains collected from fecal samples of several primate species and an Ursus arctos. Thus, we investigated the genomic variability and metabolic abilities of the new B. dentium isolates together with 20 public genome sequences. Comparative genomic analyses provided insights into the vast metabolic repertoire of the species, highlighting 19 glycosyl hydrolases families shared between each analyzed strain. Phylogenetic analysis of the B. dentium taxon, involving 1140 conserved genes, revealed a very close phylogenetic relatedness among members of this species. Furthermore, low genomic variability between strains was also confirmed by an average nucleotide identity analysis showing values higher than 98.2%. Investigating the genetic features of each strain, few putative functional mobile elements were identified. Besides, a consistent occurrence of defense mechanisms such as CRISPR–Cas and restriction–modification systems may be responsible for the high genome synteny identified among members of this taxon.
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The Genome Sequence of Bifidobacterium moukalabense DSM 27321 Highlights the Close Phylogenetic Relatedness with the Bifidobacterium dentium Taxon.
Genome announcements, 2014Co-Authors: Gabriele Andrea Lugli, Sabrina Duranti, Alice Viappiani, Christian Milani, Francesca Turroni, D. Van Sinderen, Marta Mangifesta, Marco VenturaAbstract:ABSTRACT Bifidobacterium moukalabense DSM 27321 is the reference strain for a recently described new bifidobacterial species that has been isolated from a wild west lowland gorilla. Here, we report the whole-genome sequence of DSM 27321, which supports very close phylogenetic relatedness with members of the Bifidobacterium adolescentis phylogenetic group and, in particular, the Bifidobacterium dentium taxon.
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The Bifidobacterium dentium Bd1 Genome Sequence Reflects Its Genetic Adaptation to the Human Oral Cavity
2013Co-Authors: Marco Ventura, Francesca Turroni, Maria Mantzourani, Vanessa Giubellini, Aldert Zomer, Elena Foroni, Carlos Canchaya, Marcus J Claesson, Laura MulasAbstract:Bifidobacteria, one of the relatively dominant components of the human intestinal microbiota, are considered one of the key groups of beneficial intestinal bacteria (probiotic bacteria). However, in addition to health-promoting taxa, the genus Bifidobacterium also includes Bifidobacterium dentium, an opportunistic cariogenic pathogen. The genetic basis for the ability of B. dentium to survive in the oral cavity and contribute to caries development is not understood. The genome of B. dentium Bd1, a strain isolated from dental caries, was sequenced to completion to uncover a single circular 2,636,368 base pair chromosome with 2,143 predicted open reading frames. Annotation of the genome sequence revealed multiple ways in which B. dentium has adapted to the oral environment through specialized nutrient acquisition, defences against antimicrobials, and gene products that increase fitness and competitiveness within the oral niche. B. dentium Bd1 wa
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Genetic analysis and morphological identification of pilus-like structures in members of the genus Bifidobacterium
2011Co-Authors: E. Foroni, Alice Viappiani, Francesca Turroni, Francesca Bottacini, F. Serafini, D. Amidani, O’connell M. Motherway, Z. Zhang, C. RivettiAbstract:Background: Cell surface pili in Gram positive bacteria have been reported to orchestrate the colonization of host tissues, evasion of immunity and the development of biofilms. So far, little if any information is available on the presence of pilus-like structures in human gut commensals like bifidobacteria. Results and discussion: In this report, Atomic Force Microscopy (AFM) of various bifidobacterial strains belonging to Bifidobacterium bifidum, Bifidobacterium longum subsp. longum, Bifidobacterium dentium, Bifidobacterium adolescentis and Bifidobacterium animalis subsp. lactis revealed the existence of appendages resembling pilus-like structures. Interestingly, these microorganisms harbour two to six predicted pilus gene clusters in their genome, with each organized in an operon encompassing the major pilin subunit-encoding gene (designated fimA or fimP) together with one or two minor pilin subunit-encoding genes (designated as fimB and/or fimQ), and a gene encoding a sortase enzyme (strA). Quantitative Real Time (qRT)-PCR analysis and RT-PCR experiments revealed a polycistronic mRNA, encompassing the fimA/P and fimB/Q genes, which are differentially expressed upon cultivation of bifidobacteria on various glycans
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PROCEEDINGS Open Access Genetic analysis and morphological identification of pilus-like structures in members of the genus
2011Co-Authors: Elena Foroni, Francesca Turroni, Francesca Bottacini, F. Serafini, D. Amidani, Marco VenturaAbstract:Background: Cell surface pili in Gram positive bacteria have been reported to orchestrate the colonization of host tissues, evasion of immunity and the development of biofilms. So far, little if any information is available on the presence of pilus-like structures in human gut commensals like bifidobacteria. Results and discussion: In this report, Atomic Force Microscopy (AFM) of various bifidobacterial strains belonging to Bifidobacterium bifidum, Bifidobacterium longum subsp. longum, Bifidobacterium dentium, Bifidobacterium adolescentis and Bifidobacterium animalis subsp. lactis revealed the existence of appendages resembling pilus-like structures. Interestingly, these microorganisms harbour two to six predicted pilus gene clusters in their genome, with each organized in an operon encompassing the major pilin subunit-encoding gene (designated fimA or fimP) together with one or two minor pilin subunit-encoding genes (designated as fimB and/or fimQ), and a gene encoding a sortase enzyme (strA). Quantitative Real Time (qRT)-PCR analysis and RT-PCR experiments revealed a polycistronic mRNA, encompassing the fimA/P and fimB/Q genes, which are differentially expressed upon cultivation of bifidobacteria on various glycans
Marco Ventura - One of the best experts on this subject based on the ideXlab platform.
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The Genome Sequence of Bifidobacterium moukalabense DSM 27321 Highlights the Close Phylogenetic Relatedness with the Bifidobacterium dentium Taxon.
Genome announcements, 2014Co-Authors: Gabriele Andrea Lugli, Sabrina Duranti, Alice Viappiani, Christian Milani, Francesca Turroni, D. Van Sinderen, Marta Mangifesta, Marco VenturaAbstract:ABSTRACT Bifidobacterium moukalabense DSM 27321 is the reference strain for a recently described new bifidobacterial species that has been isolated from a wild west lowland gorilla. Here, we report the whole-genome sequence of DSM 27321, which supports very close phylogenetic relatedness with members of the Bifidobacterium adolescentis phylogenetic group and, in particular, the Bifidobacterium dentium taxon.
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The Bifidobacterium dentium Bd1 Genome Sequence Reflects Its Genetic Adaptation to the Human Oral Cavity
2013Co-Authors: Marco Ventura, Francesca Turroni, Maria Mantzourani, Vanessa Giubellini, Aldert Zomer, Elena Foroni, Carlos Canchaya, Marcus J Claesson, Laura MulasAbstract:Bifidobacteria, one of the relatively dominant components of the human intestinal microbiota, are considered one of the key groups of beneficial intestinal bacteria (probiotic bacteria). However, in addition to health-promoting taxa, the genus Bifidobacterium also includes Bifidobacterium dentium, an opportunistic cariogenic pathogen. The genetic basis for the ability of B. dentium to survive in the oral cavity and contribute to caries development is not understood. The genome of B. dentium Bd1, a strain isolated from dental caries, was sequenced to completion to uncover a single circular 2,636,368 base pair chromosome with 2,143 predicted open reading frames. Annotation of the genome sequence revealed multiple ways in which B. dentium has adapted to the oral environment through specialized nutrient acquisition, defences against antimicrobials, and gene products that increase fitness and competitiveness within the oral niche. B. dentium Bd1 wa
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PROCEEDINGS Open Access Genetic analysis and morphological identification of pilus-like structures in members of the genus
2011Co-Authors: Elena Foroni, Francesca Turroni, Francesca Bottacini, F. Serafini, D. Amidani, Marco VenturaAbstract:Background: Cell surface pili in Gram positive bacteria have been reported to orchestrate the colonization of host tissues, evasion of immunity and the development of biofilms. So far, little if any information is available on the presence of pilus-like structures in human gut commensals like bifidobacteria. Results and discussion: In this report, Atomic Force Microscopy (AFM) of various bifidobacterial strains belonging to Bifidobacterium bifidum, Bifidobacterium longum subsp. longum, Bifidobacterium dentium, Bifidobacterium adolescentis and Bifidobacterium animalis subsp. lactis revealed the existence of appendages resembling pilus-like structures. Interestingly, these microorganisms harbour two to six predicted pilus gene clusters in their genome, with each organized in an operon encompassing the major pilin subunit-encoding gene (designated fimA or fimP) together with one or two minor pilin subunit-encoding genes (designated as fimB and/or fimQ), and a gene encoding a sortase enzyme (strA). Quantitative Real Time (qRT)-PCR analysis and RT-PCR experiments revealed a polycistronic mRNA, encompassing the fimA/P and fimB/Q genes, which are differentially expressed upon cultivation of bifidobacteria on various glycans
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the Bifidobacterium dentium bd1 genome sequence reflects its genetic adaptation to the human oral cavity
PLOS Genetics, 2009Co-Authors: Marco Ventura, Francesca Turroni, Maria Mantzourani, Vanessa Giubellini, Aldert Zomer, Elena Foroni, Francesca Bottacini, Carlos Canchaya, Marcus J Claesson, Laura MulasAbstract:Bifidobacteria, one of the relatively dominant components of the human intestinal microbiota, are considered one of the key groups of beneficial intestinal bacteria (probiotic bacteria). However, in addition to health-promoting taxa, the genus Bifidobacterium also includes Bifidobacterium dentium, an opportunistic cariogenic pathogen. The genetic basis for the ability of B. dentium to survive in the oral cavity and contribute to caries development is not understood. The genome of B. dentium Bd1, a strain isolated from dental caries, was sequenced to completion to uncover a single circular 2,636,368 base pair chromosome with 2,143 predicted open reading frames. Annotation of the genome sequence revealed multiple ways in which B. dentium has adapted to the oral environment through specialized nutrient acquisition, defences against antimicrobials, and gene products that increase fitness and competitiveness within the oral niche. B. dentium Bd1 was shown to metabolize a wide variety of carbohydrates, consistent with genome-based predictions, while colonization and persistence factors implicated in tissue adhesion, acid tolerance, and the metabolism of human saliva-derived compounds were also identified. Global transcriptome analysis demonstrated that many of the genes encoding these predicted traits are highly expressed under relevant physiological conditions. This is the first report to identify, through various genomic approaches, specific genetic adaptations of a Bifidobacterium taxon, Bifidobacterium dentium Bd1, to a lifestyle as a cariogenic microorganism in the oral cavity. In silico analysis and comparative genomic hybridization experiments clearly reveal a high level of genome conservation among various B. dentium strains. The data indicate that the genome of this opportunistic cariogen has evolved through a very limited number of horizontal gene acquisition events, highlighting the narrow boundaries that separate commensals from opportunistic pathogens.
Melinda A. Engevik - One of the best experts on this subject based on the ideXlab platform.
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the metabolic profile of Bifidobacterium dentium reflects its status as a human gut commensal
BMC Microbiology, 2021Co-Authors: Melinda A. Engevik, Anne Hall, Heather A Danhof, Kristen A Engevik, Thomas D Horvath, Sigmund J HaidacherAbstract:Bifidobacteria are commensal microbes of the mammalian gastrointestinal tract. In this study, we aimed to identify the intestinal colonization mechanisms and key metabolic pathways implemented by Bifidobacterium dentium. B. dentium displayed acid resistance, with high viability over a pH range from 4 to 7; findings that correlated to the expression of Na+/H+ antiporters within the B. dentium genome. B. dentium was found to adhere to human MUC2+ mucus and harbor mucin-binding proteins. Using microbial phenotyping microarrays and fully-defined media, we demonstrated that in the absence of glucose, B. dentium could metabolize a variety of nutrient sources. Many of these nutrient sources were plant-based, suggesting that B. dentium can consume dietary substances. In contrast to other bifidobacteria, B. dentium was largely unable to grow on compounds found in human mucus; a finding that was supported by its glycosyl hydrolase (GH) profile. Of the proteins identified in B. dentium by proteomic analysis, a large cohort of proteins were associated with diverse metabolic pathways, indicating metabolic plasticity which supports colonization of the dynamic gastrointestinal environment. Taken together, we conclude that B. dentium is well adapted for commensalism in the gastrointestinal tract.
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human derived Bifidobacterium dentium modulates the mammalian serotonergic system and gut brain axis
Cellular and molecular gastroenterology and hepatology, 2021Co-Authors: Melinda A. Engevik, Anne Hall, Zhongcheng Shi, Alexandra Changgraham, Heather A Danhof, Berkley Luck, Chonnikant Visuthranukul, Faith D Ihekweazu, Amy C Engevik, Bradley T. EndresAbstract:Background & Aims The human gut microbiota can regulate production of serotonin (5-hydroxytryptamine [5-HT]) from enterochromaffin cells. However, the mechanisms underlying microbial-induced serotonin signaling are not well understood. Methods Adult germ-free mice were treated with sterile media, live Bifidobacterium dentium, heat-killed B dentium, or live Bacteroides ovatus. Mouse and human enteroids were used to assess the effects of B dentium metabolites on 5-HT release from enterochromaffin cells. In vitro and in vivo short-chain fatty acids and 5-HT levels were assessed by mass spectrometry. Expression of tryptophan hydroxylase, short-chain fatty acid receptor free fatty acid receptor 2, 5-HT receptors, and the 5-HT re-uptake transporter (serotonin transporter) were assessed by quantitative polymerase chain reaction and immunostaining. RNA in situ hybridization assessed 5-HT–receptor expression in the brain, and 5-HT–receptor–dependent behavior was evaluated using the marble burying test. Results B dentium mono-associated mice showed increased fecal acetate. This finding corresponded with increased intestinal 5-HT concentrations and increased expression of 5-HT receptors 2a, 4, and serotonin transporter. These effects were absent in B ovatus-treated mice. Application of acetate and B dentium–secreted products stimulated 5-HT release in mouse and human enteroids. In situ hybridization of brain tissue also showed significantly increased hippocampal expression of 5-HT–receptor 2a in B dentium–treated mice relative to germ-free controls. Functionally, B dentium colonization normalized species-typical repetitive and anxiety-like behaviors previously shown to be linked to 5-HT–receptor 2a. Conclusions These data suggest that B dentium, and the bacterial metabolite acetate, are capable of regulating key components of the serotonergic system in multiple host tissues, and are associated with a functional change in adult behavior.
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Bifidobacterium dentium-derived y-glutamylcysteine suppresses ER-mediated goblet cell stress and reduces TNBS-driven colonic inflammation
'Informa UK Limited', 2021Co-Authors: Melinda A. Engevik, Alexandra L. Chang-graham, Beatrice Herrmann, Wenly Ruan, Zhongcheng Shi, Kristen A Engevik, Berkley Luck, Amy C Engevik, Faith Ihekweazu, Magdalena EsparzaAbstract:Endoplasmic reticulum (ER) stress compromises the secretion of MUC2 from goblet cells and has been linked with inflammatory bowel disease (IBD). Although Bifidobacterium can beneficially modulate mucin production, little work has been done investigating the effects of Bifidobacterium on goblet cell ER stress. We hypothesized that secreted factors from Bifidobacterium dentium downregulate ER stress genes and modulates the unfolded protein response (UPR) to promote MUC2 secretion. We identified by mass spectrometry that B. dentium secretes the antioxidant γ-glutamylcysteine, which we speculate dampens ER stress-mediated ROS and minimizes ER stress phenotypes. B. dentium cell-free supernatant and γ-glutamylcysteine were taken up by human colonic T84 cells, increased glutathione levels, and reduced ROS generated by the ER-stressors thapsigargin and tunicamycin. Moreover, B. dentium supernatant and γ-glutamylcysteine were able to suppress NF-kB activation and IL-8 secretion. We found that B. dentium supernatant, γ-glutamylcysteine, and the positive control IL-10 attenuated the induction of UPR genes GRP78, CHOP, and sXBP1. To examine ER stress in vivo, we first examined mono-association of B. dentium in germ-free mice which increased MUC2 and IL-10 levels compared to germ-free controls. However, no changes were observed in ER stress-related genes, indicating that B. dentium can promote mucus secretion without inducing ER stress. In a TNBS-mediated ER stress model, we observed increased levels of UPR genes and pro-inflammatory cytokines in TNBS treated mice, which were reduced with addition of live B. dentium or γ-glutamylcysteine. We also observed increased colonic and serum levels of IL-10 in B. dentium- and γ-glutamylcysteine-treated mice compared to vehicle control. Immunostaining revealed retention of goblet cells and mucus secretion in both B. dentium- and γ-glutamylcysteine-treated animals. Collectively, these data demonstrate positive modulation of the UPR and MUC2 production by B. dentium-secreted compounds
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Bifidobacterium dentium fortifies the intestinal mucus layer via autophagy and calcium signaling pathways
Mbio, 2019Co-Authors: Berkley Luk, Melinda A. Engevik, Anne Hall, Beatrice Herrmann, Alexandra Changgraham, Wenly RuanAbstract:Much remains unknown about how the intestinal microbiome interfaces with the protective intestinal mucus layer. Bifidobacterium species colonize the intestinal mucus layer and can modulate mucus production by goblet cells. However, select Bifidobacterium strains can also degrade protective glycans on mucin proteins. We hypothesized that the human-derived species Bifidobacterium dentium would increase intestinal mucus synthesis and expulsion, without extensive degradation of mucin glycans. In silico data revealed that B. dentium lacked the enzymes necessary to extensively degrade mucin glycans. This finding was confirmed by demonstrating that B. dentium could not use naive mucin glycans as primary carbon sources in vitro To examine B. dentium mucus modulation in vivo, Swiss Webster germfree mice were monoassociated with live or heat-killed B. dentium Live B. dentium-monoassociated mice exhibited increased colonic expression of goblet cell markers Kruppel-like factor 4 (Klf4), Trefoil factor 3 (Tff3), Relm-β, Muc2, and several glycosyltransferases compared to both heat-killed B. dentium and germfree counterparts. Likewise, live B. dentium-monoassociated colon had increased acidic mucin-filled goblet cells, as denoted by Periodic Acid-Schiff-Alcian Blue (PAS-AB) staining and MUC2 immunostaining. In vitro, B. dentium-secreted products, including acetate, were able to increase MUC2 levels in T84 cells. We also identified that B. dentium-secreted products, such as γ-aminobutyric acid (GABA), stimulated autophagy-mediated calcium signaling and MUC2 release. This work illustrates that B. dentium is capable of enhancing the intestinal mucus layer and goblet cell function via upregulation of gene expression and autophagy signaling pathways, with a net increase in mucin production.IMPORTANCE Microbe-host interactions in the intestine occur along the mucus-covered epithelium. In the gastrointestinal tract, mucus is composed of glycan-covered proteins, or mucins, which are secreted by goblet cells to form a protective gel-like structure above the epithelium. Low levels of mucin or alterations in mucin glycans are associated with inflammation and colitis in mice and humans. Although current literature links microbes to the modulation of goblet cells and mucins, the molecular pathways involved are not yet fully understood. Using a combination of gnotobiotic mice and mucus-secreting cell lines, we have identified a human-derived microbe, Bifidobacterium dentium, which adheres to intestinal mucus and secretes metabolites that upregulate the major mucin MUC2 and modulate goblet cell function. Unlike other Bifidobacterium species, B. dentium does not extensively degrade mucin glycans and cannot grow on mucin alone. This work points to the potential of using B. dentium and similar mucin-friendly microbes as therapeutic agents for intestinal disorders with disruptions in the mucus barrier.
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Bifidobacterium dentium Fortifies the Intestinal Mucus Layer via Autophagy and Calcium Signaling Pathways
'American Society for Microbiology', 2019Co-Authors: Melinda A. Engevik, Berkley Luk, Alexandra L. Chang-graham, Anne Hall, Beatrice Herrmann, Wenly Ruan, Bradley T. Endres, Zhongcheng Shi, Kevin W. Garey, Joseph M. HyserAbstract:Microbe-host interactions in the intestine occur along the mucus-covered epithelium. In the gastrointestinal tract, mucus is composed of glycan-covered proteins, or mucins, which are secreted by goblet cells to form a protective gel-like structure above the epithelium. Low levels of mucin or alterations in mucin glycans are associated with inflammation and colitis in mice and humans. Although current literature links microbes to the modulation of goblet cells and mucins, the molecular pathways involved are not yet fully understood. Using a combination of gnotobiotic mice and mucus-secreting cell lines, we have identified a human-derived microbe, Bifidobacterium dentium, which adheres to intestinal mucus and secretes metabolites that upregulate the major mucin MUC2 and modulate goblet cell function. Unlike other Bifidobacterium species, B. dentium does not extensively degrade mucin glycans and cannot grow on mucin alone. This work points to the potential of using B. dentium and similar mucin-friendly microbes as therapeutic agents for intestinal disorders with disruptions in the mucus barrier.Much remains unknown about how the intestinal microbiome interfaces with the protective intestinal mucus layer. Bifidobacterium species colonize the intestinal mucus layer and can modulate mucus production by goblet cells. However, select Bifidobacterium strains can also degrade protective glycans on mucin proteins. We hypothesized that the human-derived species Bifidobacterium dentium would increase intestinal mucus synthesis and expulsion, without extensive degradation of mucin glycans. In silico data revealed that B. dentium lacked the enzymes necessary to extensively degrade mucin glycans. This finding was confirmed by demonstrating that B. dentium could not use naive mucin glycans as primary carbon sources in vitro. To examine B. dentium mucus modulation in vivo, Swiss Webster germfree mice were monoassociated with live or heat-killed B. dentium. Live B. dentium-monoassociated mice exhibited increased colonic expression of goblet cell markers Krüppel-like factor 4 (Klf4), Trefoil factor 3 (Tff3), Relm-β, Muc2, and several glycosyltransferases compared to both heat-killed B. dentium and germfree counterparts. Likewise, live B. dentium-monoassociated colon had increased acidic mucin-filled goblet cells, as denoted by Periodic Acid-Schiff-Alcian Blue (PAS-AB) staining and MUC2 immunostaining. In vitro, B. dentium-secreted products, including acetate, were able to increase MUC2 levels in T84 cells. We also identified that B. dentium-secreted products, such as γ-aminobutyric acid (GABA), stimulated autophagy-mediated calcium signaling and MUC2 release. This work illustrates that B. dentium is capable of enhancing the intestinal mucus layer and goblet cell function via upregulation of gene expression and autophagy signaling pathways, with a net increase in mucin production
Pedro Mena - One of the best experts on this subject based on the ideXlab platform.
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differential catabolism of an anthocyanin rich elderberry extract by three gut microbiota bacterial species
Journal of Agricultural and Food Chemistry, 2020Co-Authors: Letizia Bresciani, Donato Angelino, Eugenio I Vivas, Robert L Kerby, Cristina Garciaviguera, Daniele Del Rio, Federico E Rey, Pedro MenaAbstract:Elderberries are good sources of anthocyanins, which are poorly absorbed in the upper gastrointestinal tract but extensively transformed into phenolic metabolites at the colonic level. Because different gut microbiota strains have different metabolism, the catabolism of anthocyanins may lead to interindividual differences in metabolite production. In this work, an anthocyanin-rich elderberry extract was incubated with three single gut microbial strains (Enterobacter cancerogenous, Bifidobacterium dentium, and Dorea longicatena) up to 4 days, to assess differences in their phenolic metabolism. All of the strains degraded the elderberry anthocyanins, but the metabolic pathways followed were different. Although some metabolites were common for all of the strains, a wide disparity was observed in the kind and amount of several phenolic metabolites produced by each species. These in vitro preliminary results may be of help in the interpretation of the bioavailability of anthocyanins and give a clue to understand interindividual variability in metabolite production.
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Differential Catabolism of an Anthocyanin-Rich Elderberry Extract by Three Gut Microbiota Bacterial Species
2019Co-Authors: Letizia Bresciani, Donato Angelino, Eugenio I Vivas, Robert L Kerby, Daniele Del Rio, Federico E Rey, Cristina García-viguera, Pedro MenaAbstract:Elderberries are good sources of anthocyanins, which are poorly absorbed in the upper gastrointestinal tract but extensively transformed into phenolic metabolites at the colonic level. Because different gut microbiota strains have different metabolism, the catabolism of anthocyanins may lead to interindividual differences in metabolite production. In this work, an anthocyanin-rich elderberry extract was incubated with three single gut microbial strains (Enterobacter cancerogenous, Bifidobacterium dentium, and Dorea longicatena) up to 4 days, to assess differences in their phenolic metabolism. All of the strains degraded the elderberry anthocyanins, but the metabolic pathways followed were different. Although some metabolites were common for all of the strains, a wide disparity was observed in the kind and amount of several phenolic metabolites produced by each species. These in vitro preliminary results may be of help in the interpretation of the bioavailability of anthocyanins and give a clue to understand interindividual variability in metabolite production