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Abelardo Margolles - One of the best experts on this subject based on the ideXlab platform.

  • Insights into the Ropy Phenotype of the Exopolysaccharide-Producing Strain Bifidobacterium animalis subsp. lactis A1dOxR
    Applied and environmental microbiology, 2013
    Co-Authors: Claudio Hidalgo-cantabrana, Miguel Gueimonde, Clara G. De Los Reyes-gavilán, Abelardo Margolles, Borja Sánchez, Deborah Moine, Bernard Berger, Patricia Ruas-madiedo
    Abstract:

    The proteome of the ropy strain Bifidobacterium animalis subsp. lactis A1dOxR, compared to that of its nonropy isogenic strain, showed an overproduction of a protein involved in rhamnose biosynthesis. Results were confirmed by gene expression analysis, and this fact agreed with the high rhamnose content of the ropy exopolysaccharide.

  • Selection of a Bifidobacterium animalis subsp. lactis Strain with a Decreased Ability To Produce Acetic Acid
    Applied and environmental microbiology, 2012
    Co-Authors: Abelardo Margolles, Borja Sánchez
    Abstract:

    We have characterized a new strain, Bifidobacterium animalis subsp. lactis CECT 7953, obtained by random UV mutagenesis, which produces less acetic acid than the wild type (CECT 7954) in three different experimental settings: De Man-Rogosa-Sharpe broth without sodium acetate, resting cells, and skim milk. Genome sequencing revealed a single Phe-Ser substitution in the acetate kinase gene product that seems to be responsible for the strain's reduced acid production. Accordingly, acetate kinase specific activity was lower in the low acetate producer. Strain CECT 7953 produced less acetate, less ethanol, and more yoghourt-related volatile compounds in skim milk than the wild type did. Thus, CECT 7953 shows promising potential for the development of dairy products fermented exclusively by a bifidobacterial strain.

  • Genetic basis of tetracycline resistance in Bifidobacterium animalis subsp. lactis.
    Applied and environmental microbiology, 2010
    Co-Authors: Miguel Gueimonde, Clara G. De Los Reyes-gavilán, Ana Belén Flórez, Angela H.a.m. Van Hoek, Birgitte Stuer-lauridsen, Per Strøman, Abelardo Margolles
    Abstract:

    All strains of Bifidobacterium animalis subsp. lactis described to date show medium level resistance to tetracycline. Screening of 26 strains from a variety of sources revealed the presence of tet(W) in all isolates. A transposase gene upstream of tet(W) was found in all strains, and both genes were cotranscribed in strain IPLAIC4. Mutants with increased tetracycline resistance as well as tetracycline-sensitive mutants of IPLAIC4 were isolated and genetically characterized. The native tet(W) gene was able to restore the resistance phenotype to a mutant with an alteration in tet(W) by functional complementation, indicating that tet(W) is necessary and sufficient for the tetracycline resistance seen in B. animalis subsp. lactis.

  • Technological and probiotic selection criteria of a bile-adapted Bifidobacterium animalis subsp. lactis strain
    International Dairy Journal, 2010
    Co-Authors: Borja Sánchez, Abelardo Margolles, Clara G. De Los Reyes-gavilán, María Fernández-garcía, Patricia Ruas-madiedo
    Abstract:

    The technological and probiotic properties of the bile-adapted strain Bifidobacterium animalis subsp. lactis 4549dOx have been studied in comparison with its parental strain IPLA4549. The survival of the bile-adapted derivative to the simulated gastrointestinal transit was significantly higher than that of the parental strain, except in the presence of 10% skimmed milk. The adherence of strain 4549dOx to the intestinal cell line HT29-MTX almost duplicated that of strain IPLA4549. However, both strains had similar behaviour throughout the shelf-life of fermented milk. In conclusion, the bile-adapted strain 4549dOx presented advantages for its inclusion in dairy probiotic foods.

  • Bile affects the synthesis of exopolysaccharides by Bifidobacterium animalis.
    Applied and environmental microbiology, 2008
    Co-Authors: Patricia Ruas-madiedo, Miguel Gueimonde, Fabrizio Arigoni, Clara G. De Los Reyes-gavilán, Abelardo Margolles
    Abstract:

    By using cryo-scanning electron microscopy and quantification with lectin-conjugated probes, we have detected the production of exopolysaccharides (EPS) in Bifidobacterium animalis subsp. lactis in the presence of bile. In addition, the expression of gtf01207, which codifies a putative priming glycosyltransferase involved in EPS synthesis, was induced by bile.

Nan Shang - One of the best experts on this subject based on the ideXlab platform.

  • Complete genome sequence of Bifidobacterium animalis RH, a probiotic bacterium producing exopolysaccharides ☆
    Journal of biotechnology, 2014
    Co-Authors: Lei Liu, Yuxuan Qin, Wang Yang, Nan Shang
    Abstract:

    Abstract Bifidobacterium animalis RH is a probiotic bacterium producing exopolysaccharides, which was isolated from the feces of Bama centenarians in Guangxi, China. The genome consists of one chromosome (1,931,057 bp) with no plasmid. The genomic sequence indicated that this strain includes a gene cluster involved in exopolysaccharides (EPS) biosynthesis. Genome sequencing information provides the basis for analysis of molecular mechanisms responsible for regulation of production of EPS.

  • Structure characterization of an exopolysaccharide produced by Bifidobacterium animalis RH
    Carbohydrate polymers, 2012
    Co-Authors: Nan Shang
    Abstract:

    An exopolysaccharide fraction (EPSb) produced by Bifidobacterium animalis RH isolated from the feces of centenarians was purified to illustrate its structure and conformational characterization. Results from Fourier-transform infrared spectrometry, gel permeation chromatography, high-pH anion-exchange chromatography with pulsed amperometric detection, periodate oxidation and Smith degradation, methylation and gas chromatography-mass spectrometry, and nuclear magnetic response analysis indicated that EPSb (M(w)=21.3 kDa) was composed of rhamnose (Rha), arabinose (Ara), galactose (Gal), glucose (Glc), and mannose (Man) in a molar ratio of 0.4:0.3:1.6:0.8:1.2. This compound had a backbone of (1→3,4)-linked Man, (1→4)-linked Rha, (1→4)-linked Gal, and (1→4)-linked Glc. It was branched with Gal and terminated with Gal and Glc residues. The molecular structure of EPSb was observed via atomic force microscopy. EPSb showed spherical lumps and a ring-like network. Conformational analysis revealed the non-triple helical conformation of EPSb.

  • In vitro and in vivo antioxidant activity of exopolysaccharide fractions from Bifidobacterium animalis RH.
    Anaerobe, 2011
    Co-Authors: Nan Shang
    Abstract:

    The aim of the study was to purify the exopolysaccharides (EPS) produced from Bifidobacterium animalis RH, which was isolated from the feces of Bama centenarians in Guangxi of China, and evaluate their antioxidant activities in vitro and in vivo. 2 fractions, a neutral EPS fraction (EPSa) and an acidic EPS fraction (EPSb), were obtained and compared for antioxidative activity. In vitro, they both showed remarkable inhibition effect on lipid peroxidation and strong DPPH radical scavenging activity, hydroxyl radical scavenging activity, superoxide radical scavenging activity, in which the last two were measured by the electron spin resonance (ESR). In vivo, EPSa and EPSb were orally administrated for 30 days in a d-galactose induced aged mice model. As results, they both could significantly increase the activities of SOD, CAT and total antioxidant capacity (TAOC) in serums and glutathione GST in livers. They also could inhibit significantly the formation of MDA in serums and livers, and reduce the activity of MAO and lipofuscin accumulation in mice brain. Moreover, EPSb exhibited much higher antioxidant activities than EPSa in vitro and in vivo. The results suggested that EPS fractions of Bifidobacterium animalis RH had direct and potent antioxidant activities.

  • In vitro and in vivo antioxidant activity of Bifidobacterium animalis 01 isolated from centenarians.
    Current microbiology, 2010
    Co-Authors: Qian Shen, Nan Shang
    Abstract:

    Several studies reported the antioxidant activity of bifidobacteria using assays in vitro. In present study, the in vitro and in vivo antioxidant activity of Bifidobacterium animalis 01 was investigated. Culture supernatant, intact cells, and intracellular cell-free extracts of B. animalis 01 were involved in this study. The antioxidant assays in vitro included lipid peroxidation assay, 1,1-diphenyl-2-picrylhydrazyl (DPPH) assay, hydroxyl radical (•OH) assay and superoxide anion (\( {\text{O}}_{2}^{ - } \)) assay. The antioxidant assays in vivo were conducted using mice model. Activities of antioxidative enzymes, malondialdehyde (MDA) content in serums and livers of aging mice were evaluated. Monoamine oxidase (MAO) activity and lipofuscin level in brains of aging mice were also characterized. Results showed that culture supernatant, intact cells and intracellular cell-free extracts of B. animalis 01 could effectively scavenge free radicals, significantly enhance mice’s activities of antioxidative enzymes and reduce mice’s MDA content, lipofuscin level and MAO activity. Our results indicated that B. animalis 01 has the potential to be developed into a dietary antioxidant supplements.

  • Accumulation and species distribution of selenium in Se-enriched bacterial cells of the Bifidobacterium animalis 01
    Food Chemistry, 2009
    Co-Authors: Bowen Zhang, Nan Shang, Kang Zhou, Jinlan Zhang, Qian Chen, Guorong Liu, Wei Qin, Fengxiang Lin
    Abstract:

    Abstract Bifidobacterium animalis 01 (B. animalis 01) could absorb 16.7–39.6% of inorganic selenium in the medium and transform most of it into organic selenium. Most of the organic selenium (50.7–63.0%) was found in the protein fraction, 9.62–18.7% in the polysaccharide fraction, 0.273–0.754% in the nucleic acid fraction, and 20.8–30.9% in other components. Furthermore, the selenium content of different protein extractions was in the following order: Alkaline-soluble protein-bound Se (46.5–53.4%) > Water-soluble protein-bound Se (27.4–30.8%) > Salt-soluble protein-bound Se (7.79–11.9%) > Alcohol-soluble protein-bound Se (not detected). Additionally, the molecular mass of most proteins or protein subunits containing selenium was about 10–20 kDa. Analysis by LC–MS showed that selenomethionine (SeMet) is the major selenocompound in protein.

Borja Sánchez - One of the best experts on this subject based on the ideXlab platform.

  • A peptidome-based phylogeny pipeline reveals differential peptides at the strain level within Bifidobacterium animalis subsp. lactis
    Food microbiology, 2016
    Co-Authors: Aitor Blanco-míguez, Alberto Gutiérrez-jácome, Florentino Fdez-riverola, Anália Lourenço, Borja Sánchez
    Abstract:

    Bifidobacteria are gut commensal microorganisms belonging to the Actinobacteria group. Some specific strains of Bifidobacterium animalis subsp. lactis are used in functional foods as they are able to exert health-promoting effects in the human host. Due to the limited genetic variability within this subspecies, it is sometimes difficult for a manufacturer to properly track its strain once included in dairy products or functional foods. In this paper, we present a peptidome-based analysis in which the proteomes of a set of B. animalis subsp. lactis strains were digested in silico with human gut endopeptidases. The molecular masses were compared along all the strains to detect strain-specific peptides. These peptides may be interesting towards the development of methodologies for strain identification in the final product.

  • Insights into the Ropy Phenotype of the Exopolysaccharide-Producing Strain Bifidobacterium animalis subsp. lactis A1dOxR
    Applied and environmental microbiology, 2013
    Co-Authors: Claudio Hidalgo-cantabrana, Miguel Gueimonde, Clara G. De Los Reyes-gavilán, Abelardo Margolles, Borja Sánchez, Deborah Moine, Bernard Berger, Patricia Ruas-madiedo
    Abstract:

    The proteome of the ropy strain Bifidobacterium animalis subsp. lactis A1dOxR, compared to that of its nonropy isogenic strain, showed an overproduction of a protein involved in rhamnose biosynthesis. Results were confirmed by gene expression analysis, and this fact agreed with the high rhamnose content of the ropy exopolysaccharide.

  • Selection of a Bifidobacterium animalis subsp. lactis Strain with a Decreased Ability To Produce Acetic Acid
    Applied and environmental microbiology, 2012
    Co-Authors: Abelardo Margolles, Borja Sánchez
    Abstract:

    We have characterized a new strain, Bifidobacterium animalis subsp. lactis CECT 7953, obtained by random UV mutagenesis, which produces less acetic acid than the wild type (CECT 7954) in three different experimental settings: De Man-Rogosa-Sharpe broth without sodium acetate, resting cells, and skim milk. Genome sequencing revealed a single Phe-Ser substitution in the acetate kinase gene product that seems to be responsible for the strain's reduced acid production. Accordingly, acetate kinase specific activity was lower in the low acetate producer. Strain CECT 7953 produced less acetate, less ethanol, and more yoghourt-related volatile compounds in skim milk than the wild type did. Thus, CECT 7953 shows promising potential for the development of dairy products fermented exclusively by a bifidobacterial strain.

  • Technological and probiotic selection criteria of a bile-adapted Bifidobacterium animalis subsp. lactis strain
    International Dairy Journal, 2010
    Co-Authors: Borja Sánchez, Abelardo Margolles, Clara G. De Los Reyes-gavilán, María Fernández-garcía, Patricia Ruas-madiedo
    Abstract:

    The technological and probiotic properties of the bile-adapted strain Bifidobacterium animalis subsp. lactis 4549dOx have been studied in comparison with its parental strain IPLA4549. The survival of the bile-adapted derivative to the simulated gastrointestinal transit was significantly higher than that of the parental strain, except in the presence of 10% skimmed milk. The adherence of strain 4549dOx to the intestinal cell line HT29-MTX almost duplicated that of strain IPLA4549. However, both strains had similar behaviour throughout the shelf-life of fermented milk. In conclusion, the bile-adapted strain 4549dOx presented advantages for its inclusion in dairy probiotic foods.

  • Cell envelope changes in Bifidobacterium animalis ssp. lactis as a response to bile.
    FEMS microbiology letters, 2007
    Co-Authors: Lorena Ruiz, Patricia Ruas-madiedo, Clara G. De Los Reyes-gavilán, Borja Sánchez, Abelardo Margolles
    Abstract:

    Bifidobacterium animalis ssp. lactis is a probiotic frequently used as adjunct culture in fermented dairy products. In order to ensure its proper function at the intestinal level, this bacterium has to be tolerant to physiological concentrations of bile. This study examined the influence of bile on the fatty acid composition and the membrane characteristics of B. animalis IPLA 4549 and its mutant with acquired resistance to bile, B. animalis 4549dOx. Bile adaptation triggers in B. animalis 4549dOx a decrease in membrane fluidity and in the protein : phospholipid ratio, as well as a shift in the fatty acid composition of the cell. Remarkably, the presence of bile in the growth medium induced similar changes in both B. animalis cells. Furthermore, transmission electron microscopy analysis showed that bile promotes a severe distortion of the cell surface. This study provides new insights of the action of bile on the cell envelope of bifidobacteria.

Marco Candela - One of the best experts on this subject based on the ideXlab platform.

Mitsuharu Matsumoto - One of the best experts on this subject based on the ideXlab platform.

  • Bifidobacterium animalis subsp. lactis LKM512 reduces levels of intestinal trimethylamine produced by intestinal microbiota in healthy volunteers: A double-blind, placebo-controlled study
    Journal of Functional Foods, 2017
    Co-Authors: Mitsuharu Matsumoto, Yusuke Kitada, Yumi Shimomura, Yuji Naito
    Abstract:

    Abstract Previous clinical studies on the prevention of atherosclerosis with probiotics aimed only for the reduction of blood lipids. The aim of this study was to investigate the effect of probiotic Bifidobacterium animalis subsp. lactis LKM512 on colonic trimethylamine (TMA) and atherosclerosis-related markers in healthy subjects. Twenty-seven subjects (average age, 47.1 years) were assigned to receive probiotics or placebo for 12 weeks. At week 12, the fecal TMA concentration and BMI in the probiotics group was lower than that in the placebo group ( p p p

  • Chemical structure of the cell wall-associated polysaccharide of Bifidobacterium animalis subsp. lactis LKM512.
    Glycoconjugate journal, 2014
    Co-Authors: Yusuke Uemura, Mitsuharu Matsumoto
    Abstract:

    We have demonstrated that Bifidobacterium animalis subsp. lactis LKM512 had some probiotic properties in vivo and in vitro. To further understand their mechanisms, the chemical structure of the extracellular polysaccharide that constructs the cell envelope was determined. The strain was anaerobically cultured in MRS broth at 37 °C for 20 h, then the bacterial cells were harvested by centrifugation and washed. The cell wall-associated polysaccharide (CPS) was prepared from the cell wall component digested by lysozyme. The results of anion exchange and gel filtration chromatography showed that the polysaccharide was negatively charged and had a high molecular mass. The CPS was found to compose of galactopyranosyl, galactofuranosyl, glucopyranosyl and rhamnopyranosyl residues in the molar ratio of 1:1:1:3 by using methylation analysis with GC-MS and HPLC profiling. From the results of the structural characterization by 1 dimensional and 2 dimensional NMR spectroscopy, the polysaccharide was established to be a hexasaccharide repeating unit with the following structure: Open image in new window

  • Bifidobacterium lactis Meile et al. 1997 Is a Subjective Synonym of Bifidobacterium animalis (Mitsuoka 1969) Scardovi and Trovatelli 1974
    Microbiology and immunology, 2000
    Co-Authors: Yimin Cai, Mitsuharu Matsumoto, Yoshimi Benno
    Abstract:

    Bifidobacterium lactis JCM 10602T (T = type strain) and Bifidobacterium animalis JCM 1190T were found to be phenotypically similar. These strains were subjected to investigation of their genetic relationships. The 16S rRNA sequence of B. animalis JCM 1190T was aligned with that of other Bifidobacterium species. B. animalis and B. lactis were the most closely related species in the phylogenetic tree and showed a high similarity in sequences (98.8%). The levels of DNA-DNA hybridization between the type strains of B. lactis and B. animalis ranged from 85.5 to 92.3%, showing that they represent a single species. It is proposed that B. lactis should be considered as a junior subjective synonym of B. animalis.