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Sample records for bacteroides

  1. Efficient Electrotransformation of Bacteroides fragilis▿

    OpenAIRE

    Ichimura, Minoru; Nakayama-Imaohji, Haruyuki; Wakimoto, Shin; Morita, Hidetoshi; Hayashi, Tetsuya; Kuwahara, Tomomi

    2010-01-01

    This study describes refined electroporation parameters for efficient transformation of Bacteroides fragilis by plasmids prepared from laboratory strains of Escherichia coli. Development of the method used included determination of the optimal growth conditions for competent cell preparation, selectable antimicrobial resistance markers, electric field strength, and postpulse incubation time. Of the four E. coli-Bacteroides shuttle plasmids tested (pVAL-1, pVAL-2, pNLY1, and pLYL05), pLYL05 co...

  2. Chemotaxonomy of Bacteroides: a review.

    Science.gov (United States)

    Olsen, I

    1994-12-01

    The loose definition of Bacteroides, some species of which are important etiologic agents of oral diseases, has enabled isolates with only marginal similarities to be reposited in this genus. Many attempts have been made over the years to improve the taxonomy of this heterogeneous group of bacteria. The present article reviews major chemotaxonomic characters and techniques that have been used for this purpose: pigmentation, metabolites, whole-cell fatty acids, phospholipids, isoprenoid quinones, carbohydrates of lipopolysaccharide, whole-cell proteins, peptidoglycans, enzymes, pyrolysis mass spectrometry, DNA composition, restriction fragment length polymorphisms of DNA and ribosomal (r) RNA, homology of DNA and RNA, DNA-rRNA hybridization, and 16S and 5S rRNA oligonucleotide cataloging and sequencing. Despite improvements in their taxonomy, some bacteroides are still misclassified. Suggestions for further improvements in the taxonomy of bacteroides are made.

  3. Species differentiation of Bacteroides dorei from Bacteroides vulgatus and Bacteroides ovatus from Bacteroides xylanisolvens - Back to basics

    DEFF Research Database (Denmark)

    Micha Pedersen, Rune; Marmolin, Ea Sofie; Justesen, Ulrik S

    2013-01-01

    We present the results from 16S sequencing and phenotypic tests for differentiation of Bacteroides dorei from Bacteroides vulgatus and Bacteroides ovatus from Bacteroides xylanisolvens, which was not possible with MALDI-TOF MS. Testing with β-glucosidase could differentiate B. dorei from B. vulga....... vulgatus and a negative catalase reaction could identify B. xylanisolvens....

  4. Bacteremia with Bacteroides pyogenes after a cat bite

    DEFF Research Database (Denmark)

    Madsen, Ida Ringsborg; Justesen, Ulrik Stenz

    2011-01-01

    Animal bite wounds are often infected with bacteria from the animal's oral flora. We report what we believe to be the first case of bacteremia with Bacteroides pyogenes resulting from an infected cat bite.......Animal bite wounds are often infected with bacteria from the animal's oral flora. We report what we believe to be the first case of bacteremia with Bacteroides pyogenes resulting from an infected cat bite....

  5. Bacteroides gingivalis and Bacteroides intermedius recognize different sites on human fibrinogen

    International Nuclear Information System (INIS)

    Lantz, M.S.; Allen, R.D.; Bounelis, P.; Switalski, L.M.; Hook, M.

    1990-01-01

    Bacteroides (Porphyromonas) gingivalis and Bacteroides (Porphyromonas) intermedius have been implicated in the etiology of human periodontal diseases. These organisms are able to bind and degrade human fibrinogen, and these interactions may play a role in the pathogenesis of periodontal disease. In attempts to map the bacterial binding sites along the fibrinogen molecule, we have found that strains of B. gingivalis and B. intermedius, respectively, recognize spatially distant and distinct sites on the fibrinogen molecule. Isolated reduced and alkylated alpha-, beta-, and gamma-fibrinogen chains inhibited binding of 125I-fibrinogen to both Bacteroides species in a concentration-dependent manner. Plasmin fragments D and to some extent fragment E, however, produced a concentration-dependent inhibition of 125I-fibrinogen binding to B. intermedius strains but did not affect binding of 125I-fibrinogen to B. gingivalis strains. Radiolabeled fibrinogen chains and fragments were compared with 125I-fibrinogen with respect to specificity and reversibility of binding to bacteria. According to these criteria, gamma chain most closely resembled the native fibrinogen molecule in behavior toward B. gingivalis strains and fragments D most closely resembled fibrinogen in behavior toward B. intermedius strains. The ability of anti-human fibrinogen immunoglobulin G (IgG) to inhibit binding of 125I-fibrinogen to B. intermedius strains was greatly reduced by absorbing the IgG with fragments D. Absorbing the IgG with fragments D had no effect on the ability of the antibody to inhibit binding of 125I-fibrinogen to B. gingivalis strains. A purified staphylococcal fibrinogen-binding protein blocked binding of 125I-fibrinogen to B. intermedius strains but not to B. gingivalis strains

  6. Bacteroides gingivalis and Bacteroides intermedius recognize different sites on human fibrinogen

    Energy Technology Data Exchange (ETDEWEB)

    Lantz, M.S.; Allen, R.D.; Bounelis, P.; Switalski, L.M.; Hook, M. (Univ. of Alabama, Birmingham (USA))

    1990-02-01

    Bacteroides (Porphyromonas) gingivalis and Bacteroides (Porphyromonas) intermedius have been implicated in the etiology of human periodontal diseases. These organisms are able to bind and degrade human fibrinogen, and these interactions may play a role in the pathogenesis of periodontal disease. In attempts to map the bacterial binding sites along the fibrinogen molecule, we have found that strains of B. gingivalis and B. intermedius, respectively, recognize spatially distant and distinct sites on the fibrinogen molecule. Isolated reduced and alkylated alpha-, beta-, and gamma-fibrinogen chains inhibited binding of 125I-fibrinogen to both Bacteroides species in a concentration-dependent manner. Plasmin fragments D and to some extent fragment E, however, produced a concentration-dependent inhibition of 125I-fibrinogen binding to B. intermedius strains but did not affect binding of 125I-fibrinogen to B. gingivalis strains. Radiolabeled fibrinogen chains and fragments were compared with 125I-fibrinogen with respect to specificity and reversibility of binding to bacteria. According to these criteria, gamma chain most closely resembled the native fibrinogen molecule in behavior toward B. gingivalis strains and fragments D most closely resembled fibrinogen in behavior toward B. intermedius strains. The ability of anti-human fibrinogen immunoglobulin G (IgG) to inhibit binding of 125I-fibrinogen to B. intermedius strains was greatly reduced by absorbing the IgG with fragments D. Absorbing the IgG with fragments D had no effect on the ability of the antibody to inhibit binding of 125I-fibrinogen to B. gingivalis strains. A purified staphylococcal fibrinogen-binding protein blocked binding of 125I-fibrinogen to B. intermedius strains but not to B. gingivalis strains.

  7. Characteristics of bacteroids in indeterminate nodules of the leguminous tree Leucaena glauca.

    Science.gov (United States)

    Ishihara, Hironobu; Koriyama, Hiroki; Osawa, Atsushi; Zehirov, Grigor; Yamaura, Masatoshi; Kucho, Ken-ichi; Abe, Mikiko; Higashi, Shiro; Kondorosi, Eva; Mergaert, Peter; Uchiumi, Toshiki

    2011-01-01

    Rhizobia establish symbiosis with legumes. Bacteroids in indeterminate nodules of Inverted Repeat Lacking Clade (IRLC) legumes undergo terminal differentiation caused by Nodule-specific Cysteine-Rich peptides (NCRs). Microscopic observations of bacteroids and the detection of NCRs in indeterminate nodules of the non-IRLC legume Leucaena glauca were performed. A portion of the bacteroids showed moderate cell elongation, loss of membrane integrity, and multiple nucleoids. The symbiosome contained multiple bacteroids and NCR-like peptides were not detectable. These results indicate that bacteroid differentiation in L. glauca is different from that in IRLC legumes although both hosts form indeterminate nodules.

  8. A case of Bacteroides pyogenes bacteremia secondary to liver abscess.

    Science.gov (United States)

    Park, Jong Eun; Park, So-Young; Song, Dong Joon; Huh, Hee Jae; Ki, Chang-Seok; Peck, Kyong Ran; Lee, Nam Yong

    2016-12-01

    Bacteroides pyogenes, a non-spore-forming, anaerobic, gram-negative rod, is a component of the oral flora of animals and has, on occasion, been reported to cause human infection through dog or cat bites. We report the first case of B. pyogenes bacteremia secondary to liver abscess with no history of an animal bite. The microorganism was identified by 16S rRNA sequencing. Copyright © 2016 Elsevier Ltd. All rights reserved.

  9. Studies on Mucopolysaccharidases from Oral Bacteroides sp., especially on Heparinase

    OpenAIRE

    谷口, 裕朗; 藤村, 節夫; 中村, 武

    1982-01-01

    Mucopolysaccharide lyases in the cell extract from a oral strain of Bacteroides sp. produced △4, 5-unsaturated disaccharides from the several substrates including, heparan sulfate, chondroitin sulfate A (ChS-A), chondroitin sulfate C (ChS-C), hyaluronic acid and chondroitin by the elimination reaction. However this enzyme preparation did not degrade chondroitin sulfate B (ChS-B). As for production of heparinase, the presence of heparin in the culture medium was essential. These enzymes were s...

  10. Bacteriophages infecting Bacteroides as a marker for microbial source tracking.

    Science.gov (United States)

    Jofre, Joan; Blanch, Anicet R; Lucena, Francisco; Muniesa, Maite

    2014-05-15

    Bacteriophages infecting certain strains of Bacteroides are amid the numerous procedures proposed for tracking the source of faecal pollution. These bacteriophages fulfil reasonably well most of the requirements identified as appropriate for a suitable marker of faecal sources. Thus, different host strains are available that detect bacteriophages preferably in water contaminated with faecal wastes corresponding to different animal species. For phages found preferably in human faecal wastes, which are the ones that have been more extensively studied, the amounts of phages found in waters contaminated with human fecal samples is reasonably high; these amounts are invariable through the time; their resistance to natural and anthropogenic stressors is comparable to that of other relatively resistant indicator of faecal pollution such us coliphages; the abundance ratios of somatic coliphages and bacteriophages infecting Bacteroides thetaiotaomicron GA17 are unvarying in recent and aged contamination; and standardised detection methods exist. These methods are easy, cost effective and provide data susceptible of numerical analysis. In contrast, there are some uncertainties regarding their geographical stability, and consequently suitable hosts need to be isolated for different geographical areas. However, a feasible method has been described to isolate suitable hosts in a given geographical area. In summary, phages infecting Bacteroides are a marker of faecal sources that in our opinion merits being included in the "toolbox" for microbial source tracking. However, further research is still needed in order to make clear some uncertainties regarding some of their characteristics and behaviour, to compare their suitability to the one of emerging methods such us targeting Bacteroidetes by qPCR assays; or settling molecular methods for their determination. Copyright © 2014 Elsevier Ltd. All rights reserved.

  11. Bacteroides cutis,’ a new bacterial species isolated from human skin

    Directory of Open Access Journals (Sweden)

    S. Belkacemi

    2018-03-01

    Full Text Available We report the main characteristics of ‘Bacteroides cutis’ sp. nov., strain Marseille-P4118T (= CSUR P4118, a new species within the genus Bacteroides. This strain was isolated from a skin sample of a 75-year-old man from Marseille.

  12. 5S ribosomal ribonucleic acid sequences in Bacteroides and Fusobacterium: evolutionary relationships within these genera and among eubacteria in general

    Science.gov (United States)

    Van den Eynde, H.; De Baere, R.; Shah, H. N.; Gharbia, S. E.; Fox, G. E.; Michalik, J.; Van de Peer, Y.; De Wachter, R.

    1989-01-01

    The 5S ribosomal ribonucleic acid (rRNA) sequences were determined for Bacteroides fragilis, Bacteroides thetaiotaomicron, Bacteroides capillosus, Bacteroides veroralis, Porphyromonas gingivalis, Anaerorhabdus furcosus, Fusobacterium nucleatum, Fusobacterium mortiferum, and Fusobacterium varium. A dendrogram constructed by a clustering algorithm from these sequences, which were aligned with all other hitherto known eubacterial 5S rRNA sequences, showed differences as well as similarities with respect to results derived from 16S rRNA analyses. In the 5S rRNA dendrogram, Bacteroides clustered together with Cytophaga and Fusobacterium, as in 16S rRNA analyses. Intraphylum relationships deduced from 5S rRNAs suggested that Bacteroides is specifically related to Cytophaga rather than to Fusobacterium, as was suggested by 16S rRNA analyses. Previous taxonomic considerations concerning the genus Bacteroides, based on biochemical and physiological data, were confirmed by the 5S rRNA sequence analysis.

  13. A Closer Look at Bacteroides: Phylogenetic Relationship and Genomic Implications of a Life in the Human Gut

    DEFF Research Database (Denmark)

    Karlsson, Fredrik H.; Ussery, David; Nielsen, Jens

    2011-01-01

    Bacteroidetes/Chlorobi genomes to elucidate their phylogenetic relationship and to gain insight into what is separating the gut living Bacteroides and Parabacteroides genera from other Bacteroidetes/Chlorobi species. A comprehensive analysis shows that Bacteroides species have a higher number...... that Bacteroides and Parabacteroides species share a large common core of 1,085 protein families. Genome atlases illustrate that there are few and only small unique areas on the chromosomes of four Bacteroides/Parabacteroides genomes. Functional classification to clusters of othologus groups show that Bacteroides...... species are enriched in carbohydrate transport and metabolism proteins. Classification of proteins in KEGG metabolic pathways gives a detailed view of the genome’s metabolic capabilities that can be linked to its habitat. Bacteroides pectinophilus and Bacteroides capillosus do not cluster together...

  14. Persistence of Bacteroides ovatus under simulated sunlight irradiation

    KAUST Repository

    Dong, Shengkun

    2014-07-04

    Background: Bacteroides ovatus, a member of the genus Bacteroides, is considered for use in molecular-based methods as a general fecal indicator. However, knowledge on its fate and persistence after a fecal contamination event remains limited. In this study, the persistence of B. ovatus was evaluated under simulated sunlight exposure and in conditions similar to freshwater and seawater. By combining propidium monoazide (PMA) treatment and quantitative polymerase chain reaction (qPCR) detection, the decay rates of B. ovatus were determined in the presence and absence of exogenous photosensitizers and in salinity up to 39.5 parts per thousand at 27°C. Results: UVB was found to be important for B. ovatus decay, averaging a 4 log10 of decay over 6 h of exposure without the presence of extracellular photosensitizers. The addition of NaNO2, an exogenous sensitizer producing hydroxyl radicals, did not significantly change the decay rate of B. ovatus in both low and high salinity water, while the exogenous sensitizer algae organic matter (AOM) slowed down the decay of B. ovatus in low salinity water. At seawater salinity, the decay rate of B. ovatus was slower than that in low salinity water, except when both NaNO2 and AOM were present. Conclusion: The results of laboratory experiments suggest that if B. ovatus is released into either freshwater or seawater environment in the evening, 50% of it may be intact by the next morning; if it is released at noon, only 50% may be intact after a mere 5 min of full spectrum irradiation on a clear day. This study provides a mechanistic understanding to some of the important environmental relevant factors that influenced the inactivation kinetics of B. ovatus in the presence of sunlight irradiation, and would facilitate the use of B. ovatus to indicate the occurrence of fecal contamination.

  15. Differentiation of nodules of Glycine max : Ultrastructural studies of plant cells and bacteroids.

    Science.gov (United States)

    Werner, D; Mörschel, E

    1978-01-01

    Plants of Glycine max var. Caloria, infected as 14 d old seedlings with a defined titre of Rhizobium japonicum 3Il b85 in a 10 min inoculation test, develop a sharp maximum of nitrogenase activity between 17 and 25 d after infection. This maximum (14±3 nmol C2H4 h(-1) mg nodule fresh weight(-1)), expressed as per mg nodule or per plant is followed by a 15 d period of reduced nitrogen fixation (20-30% of peak activity). 11 d after infection the first bacteroids develop as single cells inside infection vacuoles in the plant cells, close to the cell wall and infection threads. As a cytological marker for peak multiplication of bacteroids and for peak N2-fixation a few days later the association of a special type of nodule mitochondria with amyloplasts is described. 20 d after inoculation, more than 80% of the volume of infected plant cells is occupied by infection vacuoles, mostly containing only one bacteroid. The storage of poly-β-hydroxybutyrate starts to accumulate at both ends of the bacteroids. Non infected plant cells are squeezed between infected cells (25d), with infection vacuoles containing now more than two (up to five) bacteroids per section. Bacteroid development including a membrane envelope is also observed in the intercellular space between plant cells. 35 d after infection, more than 50% of the bacteroid volume is occupied by poly-β-hydroxybutyrate. The ultrastructural differentiation is discussed in relation to some enzymatic data in bacteroids and plant cell cytoplasm during nodule development.

  16. Dual diaminopimelate biosynthesis pathways in Bacteroides fragilis and Clostridium thermocellum.

    Science.gov (United States)

    Hudson, André O; Klartag, Ayelet; Gilvarg, Charles; Dobson, Renwick C J; Marques, Felipe Garbelini; Leustek, Thomas

    2011-09-01

    Bacteroides fragilis and Clostridium thermocellum were recently found to synthesize diaminopimelate (DAP) by way of LL-DAP aminotransferase. Both species also contain an ortholog of meso-diaminopimelate dehydrogenase (Ddh), suggesting that they may have redundant pathways for DAP biosynthesis. The B. fragilis Ddh ortholog shows low homology with other examples of Ddh and this species belongs to a phylum, the Bacteriodetes, not previously known to contain this enzyme. By contrast, the C. thermocellum ortholog is well conserved with known examples of Ddh. Using in vitro and in vivo assays both the B. fragilis and C. thermocellum enzymes were found to be authentic examples of Ddh, displaying kinetic properties typical of this enzyme. The result indicates that B. fragilis contains a sequence diverged form of Ddh. Phylogenomic analysis of the microbial genome database revealed that 77% of species with a Ddh ortholog also contain a second pathway for DAP biosynthesis suggesting that Ddh evolved as an ancillary mechanism for DAP biosynthesis. Copyright © 2011 Elsevier B.V. All rights reserved.

  17. Sphingolipid synthesis deficiency in a mutant of Bacteroides levii

    Energy Technology Data Exchange (ETDEWEB)

    Brumleve, B.; Lev, M.

    1986-05-01

    Bacteroides levii, an anaerobic bacterium, synthesizes two sphingolipids; the sphingomyelin analogue, ceramide phosphorylethanolamine (CPE), and also ceramide phosphorylglycerol (CPG). The first enzyme in the sphingolipid pathway, 3-ketodihydro-sphingosine (3KDS) synthase, has been partially purified previously. To study subsequent steps in the pathways, mutants defective in sphingolipid synthesis were derived by ethyl methanesulfonate and nitrosoguanidine mutagenesis. Extracts of the mutant, 1075BB, show synthase activity although the cells do not synthesize CPE or CPG. The mutant differs from the wild type in that: (1) synthase activity was much diminished in the mutant, (2) sphingolipid synthesis does not occur in the mutant as evidenced by the absence of spots at sites where CPE and CPG migrate following two-dimensional thin layer chromatography, (3) incorporation of uniformly-labelled (/sup 14/C)serine carbon or (/sup 14/C)3KDS into sphingolipids was not observed in the mutant, (4) following incubation with (/sup 14/C)3KDS, radioactivity corresponding to dihydrosphingosine (DHS) and ceramide were observed in the mutant; no (/sup 14/C)DHS was detected in the wild type, and (5) enhanced incorporation of (/sup 14/C)serine carbon into two lipids not containing phosphorus was found in the mutant. The authors conclude, therefore, that this mutant, 1075BB, has a metabolic block at the terminal biosynthetic steps of sphingolipid synthesis.

  18. Rapid synthesis and metabolism of glutamate in N2-fixing bacteroids

    International Nuclear Information System (INIS)

    Salminen, S.O.; Streeter, J.G.

    1987-01-01

    Symbiotic nodule bacteroids are thought to support N 2 fixation mainly by metabolizing dicarboxylic acids to CO 2 , generating reductant and ATP required by nitrogenase. Bradyrhizobium japonicum bacteroids were isolated anaerobically and incubated at 2% O 2 with 14 C-labeled succinate, malate, glutamate, or aspartate. 14 CO 2 was collected, and the bacteroid contents separated into neutral, organic acid, and amino acid fractions. The respiration of substrates, relative to their uptake, was malate > glutamate > succinate > aspartate. Analysis of the fractions revealed that will all substrates the radioactivity was found mostly in the amino acid fraction. The labeling of the neutral fraction was negligible and only a small amount of label was found in the organic acid fraction indicating a small pool size. TLC of the amino acid fraction showed the label to be principally in glutamate. Glutamate contained 67, 80, 97, and 88% of the 14 C in the amino acid fraction in bacteroids fed with succinate, malate, glutamate and aspartate, respectively. The data suggest that glutamate may play an important role in the bacteroid function

  19. Development of EUCAST disk diffusion method for susceptibility testing of the Bacteroides fragilis group isolates

    DEFF Research Database (Denmark)

    Nagy, Elisabeth; Justesen, Ulrik Stenz; Eitel, Zsuzsa

    2015-01-01

    With the emergence of antibiotic resistance among Bacteroides fragilis group isolates the need of susceptibility testing in routine laboratories is increasing. The aims of the present study were to evaluate the disk diffusion method for susceptibility testing in case of different clinical isolates...... of Bacteroides spp by comparing zone diameter results with MICs obtained earlier during an Europe-wide antibiotic susceptibility surveillance, and to propose zone diameter breakpoints, which correlate for the EUCAST MIC breakpoints. We tested 381 clinical isolates of the B. fragilis group to amoxicillin...... testing of B. fragilis group isolates for most relevant antibiotics in routine laboratories....

  20. Multidrug-Resistant Bacteroides fragilis Bacteremia in a US Resident: An Emerging Challenge

    Directory of Open Access Journals (Sweden)

    Cristian Merchan

    2016-01-01

    Full Text Available We describe a case of Bacteroides fragilis bacteremia associated with paraspinal and psoas abscesses in the United States. Resistance to b-lactam/b-lactamase inhibitors, carbapenems, and metronidazole was encountered despite having a recent travel history to India as the only possible risk factor for multidrug resistance. Microbiological cure was achieved with linezolid, moxifloxacin, and cefoxitin.

  1. Growth inhibitory effects of endotoxins from Bacteroides gingivalis and intermedius on human gingival fibroblasts in vitro

    International Nuclear Information System (INIS)

    Layman, D.L.; Diedrich, D.L.

    1987-01-01

    Purified endotoxin or lipopolysaccharide from Bacteroides gingivalis and Bacteroides intermedius caused a similar dose-dependent inhibition of growth of cultured human gingival fibroblasts as determined by 3 H-thymidine incorporation and direct cell count. Approximately 200 micrograms/ml endotoxin caused a 50% reduction in 3 H-thymidine uptake of logarithmically growing cells. Inhibition of growth was similar in cultures of fibroblasts derived from either healthy or diseased human gingiva. When examining the change in cell number with time of exposure in culture, the rate of proliferation was significantly suppressed during the logarithmic phase of growth. However, the cells recovered so that the rate of proliferation, although reduced, was sufficient to produce a cell density similar to the control cells with prolonged culture. The endotoxins were characterized by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. The profiles of the Bacteroides endotoxins were different. B. gingivalis endotoxin showed a wide range of distinct bands indicating a heterogeneous distribution of molecular species. Endotoxin from B. intermedius exhibited a few discrete low molecular weight bands, but the majority of the lipopolysaccharides electrophoresed as a diffuse band of high molecular weight material. The apparent heterogeneity of the two Bacteroides endotoxins and the similarity in growth inhibitory capacity suggest that growth inhibitory effects of these substances cannot be attributed to any polysaccharide species of endotoxin

  2. Energy supply for dinitrogen fixation by Azotobacter vinelandii and by bacteroids of Rhizobium leguminosarum

    NARCIS (Netherlands)

    Laane, N.C.M.

    1980-01-01

    The central issue of this thesis is how obligate aerobes, such as Rhizobium leguminosarum bacteroids and Azotobacter vinelandii, generate and regulate the energy supply (in the form of ATP and reducing equivalents) for nitrogenase.
    In an effective

  3. Polysaccharides utilization in human gut bacterium Bacteroides thetaiotaomicron: comparative genomics reconstruction of metabolic and regulatory networks.

    Science.gov (United States)

    Ravcheev, Dmitry A; Godzik, Adam; Osterman, Andrei L; Rodionov, Dmitry A

    2013-12-12

    Bacteroides thetaiotaomicron, a predominant member of the human gut microbiota, is characterized by its ability to utilize a wide variety of polysaccharides using the extensive saccharolytic machinery that is controlled by an expanded repertoire of transcription factors (TFs). The availability of genomic sequences for multiple Bacteroides species opens an opportunity for their comparative analysis to enable characterization of their metabolic and regulatory networks. A comparative genomics approach was applied for the reconstruction and functional annotation of the carbohydrate utilization regulatory networks in 11 Bacteroides genomes. Bioinformatics analysis of promoter regions revealed putative DNA-binding motifs and regulons for 31 orthologous TFs in the Bacteroides. Among the analyzed TFs there are 4 SusR-like regulators, 16 AraC-like hybrid two-component systems (HTCSs), and 11 regulators from other families. Novel DNA motifs of HTCSs and SusR-like regulators in the Bacteroides have the common structure of direct repeats with a long spacer between two conserved sites. The inferred regulatory network in B. thetaiotaomicron contains 308 genes encoding polysaccharide and sugar catabolic enzymes, carbohydrate-binding and transport systems, and TFs. The analyzed TFs control pathways for utilization of host and dietary glycans to monosaccharides and their further interconversions to intermediates of the central metabolism. The reconstructed regulatory network allowed us to suggest and refine specific functional assignments for sugar catabolic enzymes and transporters, providing a substantial improvement to the existing metabolic models for B. thetaiotaomicron. The obtained collection of reconstructed TF regulons is available in the RegPrecise database (http://regprecise.lbl.gov).

  4. Possible Origins of CTnBST, a Conjugative Transposon Found Recently in a Human Colonic Bacteroides Strain▿

    Science.gov (United States)

    Schlesinger, David J.; Shoemaker, Nadja B.; Salyers, Abigail A.

    2007-01-01

    A previous survey of Bacteroides isolates suggested that the ermB gene entered Bacteroides spp. recently. Previously, ermB had been found almost exclusively in gram-positive bacteria. In one Bacteroides strain, ermB was located on 100-kb conjugative transposon (CTn) CTnBST. To assess the possible origin of this CTn, we obtained the full DNA sequence of CTnBST and used this information to investigate its possible origins. Over one-half of CTnBST had high sequence identity to a putative CTn found in the genome of Bacteroides fragilis YCH46. This included the ends of the CTn and genes involved in integration, transfer, and excision. However, the region around the ermB gene contained genes that appeared to originate from gram-positive organisms. In particular, a 7-kb segment containing the ermB gene was 100% identical to an ermB region found in the genome of the gram-positive bacterium Arcanobacterium pyogenes. A screen of Bacteroides isolates whose DNA cross-hybridized with a CTnBST probe revealed that several isolates did not carry the 7-kb region, implying that the acquisition of this region may be more recent than the acquisition of the entire CTnBST element by Bacteroides spp. We have also identified other Bacteroides isolates that carry a slightly modified 7-kb region but have no other traces of CTnBST. Thus, it is possible that this 7-kb region could itself be part of a mobile element that has inserted in a Bacteroides CTn. Our results show that CTnBST is a hybrid element which has acquired a portion of its coding region from gram-positive bacteria but which may originally have come from Bacteroides spp. or some related species. PMID:17483268

  5. Possible origins of CTnBST, a conjugative transposon found recently in a human colonic Bacteroides strain.

    Science.gov (United States)

    Schlesinger, David J; Shoemaker, Nadja B; Salyers, Abigail A

    2007-07-01

    A previous survey of Bacteroides isolates suggested that the ermB gene entered Bacteroides spp. recently. Previously, ermB had been found almost exclusively in gram-positive bacteria. In one Bacteroides strain, ermB was located on 100-kb conjugative transposon (CTn) CTnBST. To assess the possible origin of this CTn, we obtained the full DNA sequence of CTnBST and used this information to investigate its possible origins. Over one-half of CTnBST had high sequence identity to a putative CTn found in the genome of Bacteroides fragilis YCH46. This included the ends of the CTn and genes involved in integration, transfer, and excision. However, the region around the ermB gene contained genes that appeared to originate from gram-positive organisms. In particular, a 7-kb segment containing the ermB gene was 100% identical to an ermB region found in the genome of the gram-positive bacterium Arcanobacterium pyogenes. A screen of Bacteroides isolates whose DNA cross-hybridized with a CTnBST probe revealed that several isolates did not carry the 7-kb region, implying that the acquisition of this region may be more recent than the acquisition of the entire CTnBST element by Bacteroides spp. We have also identified other Bacteroides isolates that carry a slightly modified 7-kb region but have no other traces of CTnBST. Thus, it is possible that this 7-kb region could itself be part of a mobile element that has inserted in a Bacteroides CTn. Our results show that CTnBST is a hybrid element which has acquired a portion of its coding region from gram-positive bacteria but which may originally have come from Bacteroides spp. or some related species.

  6. Possible misidentification of Bacteroides sp., probably B. ureolyticus as Taylorella equigenitalis: Implications for the laboratory diagnosis of CEM

    OpenAIRE

    Moore, John; Cherie Millar, B.; Xu, Jiru; Buckley, Thomas

    2001-01-01

    International audience; A wild-type isolate with similar morphological and phenotypic properties to Taylorella equigenitalis, the causative bacterial agent of contagious equine metritis (CEM), was referred for molecular identification by PCR amplification of the 16S rRNA gene. A species-specific PCR failed to yield a product compatible with that of T. equigenitalis. The direct sequencing of the universal 16S rRNA PCR amplicon suggested the presence of a Bacteroides sp., probably Bacteroides u...

  7. Comparison of Bacteroides zoogleoformans strains isolated from soft tissue infections in cats with strains from periodontal disease in humans.

    OpenAIRE

    Love, D N; Johnson, J L; Jones, R F; Bailey, M

    1985-01-01

    A total of 11 strains of Bacteroides zoogleoformans were isolated from 11 of 106 different cat subcutaneous "fight wound" abscesses and were among a total of 143 Bacteroides species isolated from these samples. They constituted 3.4% (11 of 325) of all anaerobic isolates. The cat strains and strains of B. zoogleoformans isolated from humans with periodontal disease were similar phenotypically as determined by biochemical reactions, polyacrylamide gel electrophoresis patterns of soluble protein...

  8. Isolation of bacteriophage host strains of Bacteroides species suitable for tracking sources of animal faecal pollution in water.

    Science.gov (United States)

    Gómez-Doñate, Marta; Payán, Andrey; Cortés, Ivania; Blanch, Anicet R; Lucena, Francisco; Jofre, Juan; Muniesa, Maite

    2011-06-01

    Microbial source tracking (MST) methods allow the identification of specific faecal sources. The aim is to detect the sources of faecal pollution in a water body to allow targeted, efficient and cost-effective remediation efforts in the catchment. Bacteriophages infecting selected host strains of Bacteroides species are used as markers to track faecal contaminants in water. By using a suitable Bacteroides host from a given faecal origin, it is possible to specifically detect bacteriophages of this faecal origin. It can thus be used to detect specific phages of Bacteroides for MST. With this objective, we isolated several Bacteroides strains from pig, cow and poultry faeces by applying a previously optimized methodology used to isolate the host strains from humans. The isolated strains belonged to Bacteroides fragilis and Bacteroides thetaiotaomicron. These strains, like most Bacteroides species, detected phages of the Siphoviridae morphology. Using the newly isolated host strains for phage enumeration in a range of samples, we showed that these detect phages in faecal sources that coincide with their own origin (70-100% of the samples), and show no detection or very low percentages of detection of phages from other animal origins (from 0 to 20% of the samples). Only strains isolated from pig wastewater detected phages in 50% of human sewage samples. Nevertheless, those strains detecting phages from faecal origins other than their own detected fewer phages (2-3 log₁₀ pfu·100 ml⁻¹) than the phages detected by the specific strain of the same origin. On the basis of our results, we propose that faecal source tracking with phages infecting specific Bacteroides host strains is a useful method for MST. In addition, the method presented here is feasible in laboratories equipped with only basic microbiological equipment, it is more rapid and cost-effective than other procedures and it does not require highly qualified staff. © 2011 Society for Applied Microbiology

  9. Marsh soils as potential sinks for Bacteroides fecal indicator bacteria, Waccamaw National Wildlife Refuge, Georgetown, SC, USA

    Science.gov (United States)

    Drexler, Judith Z.; Johnson, Heather E.; Duris, Joseph W.; Krauss, Ken W.

    2014-01-01

    A soil core collected in a tidal freshwater marsh in the Waccamaw National Wildlife Refuge (Georgetown, SC) exuded a particularly strong odor of cow manure upon extrusion. In order to test for manure and determine its provenance, we carried out microbial source tracking using DNA markers for Bacteroides, a noncoliform, anaerobic bacterial group that represents a broad group of the fecal population. Three core sections from 0-3 cm, 9-12 cm and 30-33 were analyzed for the presence of Bacteroides. The ages of core sediments were estimated using 210Pb and 137Cs dating. All three core sections tested positive for Bacteroides DNA markers related to cow or deer feces. Because cow manure is stockpiled, used as fertilizer, and a source of direct contamination in the Great Pee Dee River/Winyah Bay watershed, it is very likely the source of the Bacteroides that was deposited on the marsh. The mid-points of the core sections were dated as follows: 0-3 cm: 2009; 9-12 cm: 1999, and 30-33 cm: 1961. The presence of Bacteroides at different depths/ages in the soil profile indicates that soils in tidal freshwater marshes are, at the least, capable of being short-term sinks for Bacteroides and, may have the potential to be long-term sinks of stable, naturalized populations.

  10. Multidrug-resistant Bacteroides fragilis group on the rise in Europe?

    DEFF Research Database (Denmark)

    Hartmeyer, G N; Sóki, J; Nagy, E

    2012-01-01

    We report a case of multidrug-resistance (MDR) in a strain of Bacteroides fragilis from a blood culture and abdominal fluid in a Danish patient. The patient had not been travelling for several years and had not received antibiotics prior to the present case. We also summarize the cases that have...... been reported to date of MDR B. fragilis group in Europe. As far as we know, a case like this with MDR B. fragilis has not been described in Scandinavia before....

  11. Genome sequence of the Bacteroides fragilis phage ATCC 51477-B1

    Directory of Open Access Journals (Sweden)

    Hawkins Shawn A

    2008-08-01

    Full Text Available Abstract The genome of a fecal pollution indicator phage, Bacteroides fragilis ATCC 51477-B1, was sequenced and consisted of 44,929 bases with a G+C content of 38.7%. Forty-six putative open reading frames were identified and genes were organized into functional clusters for host specificity, lysis, replication and regulation, and packaging and structural proteins.

  12. CRISPR-Cas Systems in Bacteroides fragilis, an Important Pathobiont in the Human Gut Microbiome

    Science.gov (United States)

    Tajkarimi, Mehrdad; Wexler, Hannah M.

    2017-01-01

    Background: While CRISPR-Cas systems have been identified in bacteria from a wide variety of ecological niches, there are no studies to describe CRISPR-Cas elements in Bacteroides species, the most prevalent anaerobic bacteria in the lower intestinal tract. Microbes of the genus Bacteroides make up ~25% of the total gut microbiome. Bacteroides fragilis comprises only 2% of the total Bacteroides in the gut, yet causes of >70% of Bacteroides infections. The factors causing it to transition from benign resident of the gut microbiome to virulent pathogen are not well understood, but a combination of horizontal gene transfer (HGT) of virulence genes and differential transcription of endogenous genes are clearly involved. The CRISPR-Cas system is a multi-functional system described in prokaryotes that may be involved in control both of HGT and of gene regulation. Results: Clustered regularly interspaced short palindromic repeats (CRISPR) elements in all strains of B. fragilis (n = 109) with publically available genomes were identified. Three different CRISPR-Cas types, corresponding most closely to Type IB, Type IIIB, and Type IIC, were identified. Thirty-five strains had two CRISPR-Cas types, and three strains included all three CRISPR-Cas types in their respective genomes. The cas1 gene in the Type IIIB system encoded a reverse-transcriptase/Cas1 fusion protein rarely found in prokaryotes. We identified a short CRISPR (3 DR) with no associated cas genes present in most of the isolates; these CRISPRs were found immediately upstream of a hipA/hipB operon and we speculate that this element may be involved in regulation of this operon related to formation of persister cells during antimicrobial exposure. Also, blood isolates of B. fragilis did not have Type IIC CRISPR-Cas systems and had atypical Type IIIB CRISPR-Cas systems that were lacking adjacent cas genes. Conclusions: This is the first systematic report of CRISPR-Cas systems in a wide range of B. fragilis strains

  13. CRISPR-Cas Systems in Bacteroides fragilis, an Important Pathobiont in the Human Gut Microbiome

    Directory of Open Access Journals (Sweden)

    Mehrdad Tajkarimi

    2017-11-01

    Full Text Available Background: While CRISPR-Cas systems have been identified in bacteria from a wide variety of ecological niches, there are no studies to describe CRISPR-Cas elements in Bacteroides species, the most prevalent anaerobic bacteria in the lower intestinal tract. Microbes of the genus Bacteroides make up ~25% of the total gut microbiome. Bacteroides fragilis comprises only 2% of the total Bacteroides in the gut, yet causes of >70% of Bacteroides infections. The factors causing it to transition from benign resident of the gut microbiome to virulent pathogen are not well understood, but a combination of horizontal gene transfer (HGT of virulence genes and differential transcription of endogenous genes are clearly involved. The CRISPR-Cas system is a multi-functional system described in prokaryotes that may be involved in control both of HGT and of gene regulation.Results: Clustered regularly interspaced short palindromic repeats (CRISPR elements in all strains of B. fragilis (n = 109 with publically available genomes were identified. Three different CRISPR-Cas types, corresponding most closely to Type IB, Type IIIB, and Type IIC, were identified. Thirty-five strains had two CRISPR-Cas types, and three strains included all three CRISPR-Cas types in their respective genomes. The cas1 gene in the Type IIIB system encoded a reverse-transcriptase/Cas1 fusion protein rarely found in prokaryotes. We identified a short CRISPR (3 DR with no associated cas genes present in most of the isolates; these CRISPRs were found immediately upstream of a hipA/hipB operon and we speculate that this element may be involved in regulation of this operon related to formation of persister cells during antimicrobial exposure. Also, blood isolates of B. fragilis did not have Type IIC CRISPR-Cas systems and had atypical Type IIIB CRISPR-Cas systems that were lacking adjacent cas genes.Conclusions: This is the first systematic report of CRISPR-Cas systems in a wide range of B

  14. Isolation and characterization of Bacteroides host strain HB-73 used to detect sewage specific phages in Hawaii.

    Science.gov (United States)

    Vijayavel, Kannappan; Fujioka, Roger; Ebdon, James; Taylor, Huw

    2010-06-01

    Previous studies have shown that Escherichia coli and enterococci are unreliable indicators of fecal contamination in Hawaii because of their ability to multiply in environmental soils. In this study, the method of detecting Bacteroides phages as specific markers of sewage contamination in Hawaii's recreational waters was evaluated because these sewage specific phages cannot multiply under environmental conditions. Bacteroides hosts (GB-124, GA-17), were recovered from sewage samples in Europe and were reported to be effective in detecting phages from sewage samples obtained in certain geographical areas. However, GB-124 and GA-17 hosts were ineffective in detecting phages from sewage samples obtained in Hawaii. Bacteroides host HB-73 was isolated from a sewage sample in Hawaii, confirmed as a Bacteroides sp. and shown to recover phages from multiple sources of sewage produced in Hawaii at high concentrations (5.2-7.3 x 10(5) PFU/100 mL). These Bacteroides phages were considered as potential markers of sewage because they also survived for three days in fresh stream water and two days in marine water. Water samples from Hawaii's coastal swimming beaches and harbors, which were known to be contaminated with discharges from streams, were shown to contain moderate (20-187 CFU/100 mL) to elevated (173-816 CFU/100 mL) concentrations of enterococci. These same samples contained undetectable levels (Hawaii and the most likely source of these enterococci is from environmental soil rather than from sewage. 2010 Elsevier Ltd. All rights reserved.

  15. The Glycolytic Versatility of Bacteroides uniformis CECT 7771 and Its Genome Response to Oligo and Polysaccharides

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    Alfonso Benítez-Páez

    2017-08-01

    Full Text Available Bacteroides spp. are dominant components of the phylum Bacteroidetes in the gut microbiota and prosper in glycan enriched environments. However, knowledge of the machinery of specific species isolated from humans (like Bacteroides uniformis contributing to the utilization of dietary and endogenous sources of glycans and their byproducts is limited. We have used the cutting-edge nanopore-based technology to sequence the genome of B. uniformis CECT 7771, a human symbiont with a proven pre-clinical efficacy on metabolic and immune dysfunctions in obesity animal models. We have also used massive sequencing approaches to distinguish the genome expression patterns in response to carbon sources of different complexity during growth. At genome-wide level, our analyses globally demonstrate that B. uniformis strains exhibit an expanded glycolytic capability when compared with other Bacteroides species. Moreover, by studying the growth and whole-genome expression of B. uniformis CECT 7771 in response to different carbon sources, we detected a differential growth fitness and expression patterns across the genome depending on the carbon source of the culture media. The dietary fibers used exerted different effects on B. uniformis CECT 7771 activating different molecular pathways and, therefore, allowing the production of different metabolite types with potential impact on gut health. The genome and transcriptome analysis of B. uniformis CECT 7771, in response to different carbon sources, shows its high versatility to utilize both dietary and endogenous glycans along with the production of potentially beneficial end products for both the bacterium and the host, pointing to a mechanistic basis of a mutualistic relationship.

  16. Multiple Signals Govern Utilization of a Polysaccharide in the Gut Bacterium Bacteroides thetaiotaomicron.

    Science.gov (United States)

    Schwalm, Nathan D; Townsend, Guy E; Groisman, Eduardo A

    2016-10-11

    The utilization of simple sugars is widespread across all domains of life. In contrast, the breakdown of complex carbohydrates is restricted to a subset of organisms. A regulatory paradigm for integration of complex polysaccharide breakdown with simple sugar utilization was established in the mammalian gut symbiont Bacteroides thetaiotaomicron, whereby sensing of monomeric fructose regulates catabolism of both fructose and polymeric fructans. We now report that a different regulatory paradigm governs utilization of monomeric arabinose and the arabinose polymer arabinan. We establish that (i) arabinan utilization genes are controlled by a transcriptional activator that responds to arabinan and by a transcriptional repressor that responds to arabinose, (ii) arabinose utilization genes are regulated directly by the arabinose-responding repressor but indirectly by the arabinan-responding activator, and (iii) activation of both arabinan and arabinose utilization genes requires a pleiotropic transcriptional regulator necessary for survival in the mammalian gut. Genomic analysis predicts that this paradigm is broadly applicable to the breakdown of other polysaccharides in both B. thetaiotaomicron and other gut Bacteroides spp. The uncovered mechanism enables regulation of polysaccharide utilization genes in response to both the polysaccharide and its breakdown products. Breakdown of complex polysaccharides derived from "dietary fiber" is achieved by the mammalian gut microbiota. This breakdown creates a critical nutrient source for both the microbiota and its mammalian host. Because the availability of individual polysaccharides fluctuates with variations in the host diet, members of the microbiota strictly control expression of polysaccharide utilization genes. Our findings define a regulatory architecture that controls the breakdown of a polysaccharide by a gut bacterium in response to three distinct signals. This architecture integrates perception of a complex

  17. Cloning of Bacteroides fragilis plasmid genes affecting metronidazole resistance and ultraviolet survival in Escherichia coli

    International Nuclear Information System (INIS)

    Wehnert, G.U.; Abratt, V.R.; Goodman, H.J.; Woods, D.R.

    1990-01-01

    Since reduced metronidazole causes DNA damage, resistance to metronidazole was used as a selection method for the cloning of Bacteroides fragilis genes affecting DNA repair mechanisms in Escherichia coli. Genes from B. fragilis Bf-2 were cloned on a recombinant plasmid pMT100 which made E. coli AB1157 and uvrA, B, and C mutant strains more resistant to metronidazole, but more sensitive to far uv irradiation under aerobic conditions. The loci affecting metronidazole resistance and uv sensitivity were linked and located on a 5-kb DNA fragment which originated from the small 6-kb cryptic plasmid pBFC1 present in B. fragilis Bf-2 cells

  18. Spinal epidural abscess caused by Bacteroides fragilis group after dilation and curettage for incomplete abortion

    Directory of Open Access Journals (Sweden)

    Masaki Ohyagi

    2012-01-01

    Full Text Available Spinal epidural abscess (SEA is a rare infection complicated in patients who have some risk factors such as injection-drug use, diabetes mellitus, and several illnesses. However, no case of SEA associated with abortion has been reported. Here we report a case of SEA in a 30-year-old woman after dilation and curettage for incomplete abortion. The diagnosis of SEA was done by MRI and pus was drained after the cervical discectomy. Bacteroides fragilis group was cultured from the aspirated pus sample. The patient responded to surgical drainage and antibiotics.

  19. The methylome of the gut microbiome: disparate Dam methylation patterns in intestinal Bacteroides dorei

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    Michael T. Leonard

    2014-07-01

    Full Text Available Despite the large interest in the human microbiome in recent years, there are no reports of bacterial DNA methylation in the microbiome. Here metagenomic sequencing using the Pacific Biosciences platform allowed for rapid identification of bacterial GATC methylation status of a bacterial species in human stool samples. For this work, two stool samples were chosen that were dominated by a single species, Bacteroides dorei. Based on 16S rRNA analysis, this species represented over 45% of the bacteria present in these two samples. The B. dorei genome sequence from these samples was determined and the GATC methylation sites mapped. The Bacteroides dorei genome from one subject lacked any GATC methylation and lacked the DNA adenine methyltransferase genes. In contrast, B. dorei from another subject contained 20,551 methylated GATC sites. Of the 4,970 open reading frames identified in the GATC methylated B. dorei genome, 3,184 genes were methylated as well as 1,735 GATC methylations in intergenic regions. These results suggest that DNA methylation patterns are important to consider in multi-omic analyses of microbiome samples seeking to discover the diversity of bacterial functions and may differ between disease states.

  20. Twenty-eight divergent polysaccharide loci specifying within and amongst strain capsule diversity in three strains of Bacteroides fragilis

    DEFF Research Database (Denmark)

    Patrick, S.; Blakely, G.W.; Houston, S.

    2010-01-01

    Comparison of the complete genome sequence of Bacteroides fragilis 638R originally isolated in the USA, was made with two previously sequenced strains isolated in the UK (NCTC 9343) and Japan (YCH46). The presence of 10 loci containing genes associated with polysaccharide biosynthesis, each inclu...

  1. Evaluation of Bacteroides fragilis GB-124 bacteriophages as novel human-associated faecal indicators in the United States

    Science.gov (United States)

    Phages infecting human-associated Bacteroides fragilis (GB-124 phages) have been employed in the European Union (EU) to identify human fecal pollution, but their utility for U.S. was unclear. Primary sewage effluent samples were collected seasonally from seven wastewater treatme...

  2. Escherichia coli hemoglobin protease autotransporter contributes to synergistic abscess formation and heme-dependent growth of Bacteroides fragilis.

    NARCIS (Netherlands)

    Otto, B.R.; van Dooren, S.J.M.; Dozois, C.M.; Luirink, S.; Oudega, B.

    2002-01-01

    Intra-abdominal infections (IAI) continue to be a serious clinical problem. Bacterial synergism is an important factor that influences the shift from contamination to IAI, leading to the development of lesions and abscess formation. Escherichia coli and Bacteroides fragilis are particularly abundant

  3. Comparison of Bacteroides-Prevotella 16S rRNA genetic markers for fecal samples from different animal species

    Science.gov (United States)

    Fogarty, L.R.; Voytek, M.A.

    2005-01-01

    To effectively manage surface and ground waters it is necessary to improve our ability to detect and identify sources of fecal contamination. We evaluated the use of the anaerobic bacterial group Bacteroides-Prevotella as a potential fecal indicator. Terminal restriction length polymorphism (T-RFLP) of the 16S rRNA genes from this group was used to determine differences in populations and to identify any unique populations in chickens, cows, deer, dogs, geese, horses, humans, pigs, and seagulls. The group appears to be a good potential fecal indicator in all groups tested except for avians. Cluster analysis of Bacteroides-Prevotella community T-RFLP profiles indicates that Bacteroides-Prevotella populations from samples of the same host species are much more similar to each other than to samples from different source species. We were unable to identify unique peaks that were exclusive to any source species; however, for most host species, at least one T-RFLP peak was identified to be more commonly found in that species, and a combination of peaks could be used to identify the source. T-RFLP profiles obtained from water spiked with known-source feces contained the expected diagnostic peaks from the source. These results indicate that the approach of identifying Bacteroides-Prevotella molecular markers associated with host species might be useful in identifying sources of fecal contamination in the environment.

  4. Fermentation of pectin and glucose, and activity of pectin-degrading enzymes in the rabbit caecal bacterium Bacteroides caccae

    Czech Academy of Sciences Publication Activity Database

    Sirotek, Kamil; Slováková, Lenka; Kopečný, Jan; Marounek, Milan

    2004-01-01

    Roč. 38, - (2004), s. 327-332 ISSN 0266-8254 R&D Projects: GA ČR GA525/03/0358 Institutional research plan: CEZ:AV0Z5045916 Keywords : bacteroides caccae * caecum * metabolism Subject RIV: EE - Microbiology , Virology Impact factor: 1.461, year: 2004

  5. Susceptibility of clinical isolates of Bacteroides fragilis group strains to cefoxitin, cefoperazone and ticarcillin/clavulanate

    Directory of Open Access Journals (Sweden)

    PEIXOTO JÚNIOR Arnaldo Aires

    2000-01-01

    Full Text Available A total of 40 strains of the B. fragilis group was isolated from clinical specimens in two hospital centers in Fortaleza from 1993 to 1997. The most frequently isolated species was Bacteroides fragilis (19 strains and most isolates came from intra-abdominal and wound infections. The susceptibility profile was traced for cefoxitin, cefoperazone and ticarcillin-clavulanate by using the agar dilution reference method. All isolates were susceptible to ticarcillin-clavulanate (128/2mug/ml. Resistance rates of 15 and 70% were detected to cefoxitin (64mug/ml and cefoperazone (64mug/ml, respectively. Such regional results permit a better orientation in choosing this group of antibiotics for prophylaxis and therapy especially in relation to cefoxitin, which is frequently used in the hospital centers studied.

  6. The role of efflux pumps in Bacteroides fragilis resistance to antibiotics.

    Science.gov (United States)

    Ghotaslou, Reza; Yekani, Mina; Memar, Mohammad Yousef

    2018-05-01

    The resistance of Bacteroides fragilis to the most antimicrobial agents has been reported in the world. Identification of the microbial resistance mechanisms can play an important role in controlling these resistances. Currently, B. fragilis is resistant to most antibiotics. The multi-drug efflux pumps have been shown to underlie the antimicrobial resistance in B. fragilis strains. Two types of these efflux pumps including RND and MATE can be regarded as main structures responsible for antibiotic resistance. Therefore, the strategy for suppressing of this efflux system may be useful in the treatment and control of the multidrug-resistant B. fragilis. The purpose of this study is to review the B. fragilis efflux pumps and their functions in the resistance to antibiotics. Copyright © 2018 Elsevier GmbH. All rights reserved.

  7. Origins of fermentation products formed during growth of Bacteroides ruminicola on glucose

    International Nuclear Information System (INIS)

    Mountfort, D.O.; Robertson, A.M.

    1978-01-01

    Bacteroides ruminicola grown on complex medium with glucose as carbon source gave acetate, CO 2 , formate and succinate as main fermentation products. No evidence was found for significant glucose catabolism by pathways other than the Embden-Meyerhof sequence. However, [U- 14 C] glucose fermentation gave products whose specific radioactivities were much lower than expected. There appear to be two main causes. Firstly, a rapid exchange occurred between metabolic intermediates and CO 2 , probably due to reversibility of the pathway between phosphoenolpyruvate and fumarate. Secondly, non-glucose precursors, mainly peptides and acetate, added to the medium as growth factors, also gave rise to the above end-products. The distortions that such reactions introduce into measurements of ATP molar growth yields based on product analyses and measurements of carbon flux based on radioactivity recovered in products are discussed. (author)

  8. Bacteroides gingivalis-Actinomyces viscosus cohesive interactions as measured by a quantitative binding assay

    International Nuclear Information System (INIS)

    Schwarz, S.; Ellen, R.P.; Grove, D.A.

    1987-01-01

    There is limited evidence, mostly indirect, to suggest that the adherence of Bacteroides gingivalis to teeth may be enhanced by the presence of gram-positive dental plaque bacteria like Actinomyces viscosus. The purpose of this study was to carry out direct quantitative assessments of the cohesion of B gingivalis and A. viscosus by using an in vitro assay modeled on the natural sequence in which these two species colonize the teeth. The assay allowed comparisons to be made of the adherence of 3 H-labeled B. gingivalis 2561 and 381 to saliva-coated hydroxyapatite beads (S-HA) and A. viscosus WVU627- or T14V-coated S-HA (actinobeads) in equilibrium and kinetics binding studies. A series of preliminary binding studies with 3H-labeled A. viscosus and parallel studies by scanning electron microscopy with unlabeled A. viscosus were conducted to establish a protocol by which actinobeads suitable for subsequent Bacteroides adherence experiments could be prepared. By scanning electron microscopy, the actinobeads had only small gaps of exposed S-HA between essentially irreversibly bound A. viscosus cells. Furthermore, B. gingivalis cells appeared to bind preferentially to the Actinomyces cells instead of the exposed S-HA. B. gingivalis binding to both S-HA and actinobeads was saturable with at least 2 X 10(9) to 3 X 10(9) cells per ml, and equilibrium with saturating concentrations was reached within 10 to 20 min. B. gingivalis always bound in greater numbers to the actinobeads than to S-HA. These findings provide direct measurements supporting the concept that cohesion with dental plaque bacteria like A. viscosus may foster the establishment of B. gingivalis on teeth by enhancing its adherence

  9. Susceptibility trends of Bacteroides fragilis group isolates from Buenos Aires, Argentina Tendencias en el perfil de sensibilidad de aislamientos del grupo Bacteroides fragilis obtenidos en Buenos Aires, Argentina

    Directory of Open Access Journals (Sweden)

    L. Fernández Canigia

    2007-09-01

    Full Text Available The aim of this study was to analyze the susceptibility trends to seven antibiotics of Bacteroides fragilis group isolates based on three survey studies performed by the Committee of Anaerobic Bacteria between 1989 and 2002. Fifty three, 82 and 65 B. fragilis group isolates were collected during each period. The antimicrobial agents included were: ampicillin, ampicillin-sulbactam (2:1, cefoxitin, piperacillin, imipenem, clindamycin, and metronidazole. Minimal inhibitory concentrations (MICs were determined according to the reference agar dilution method described by the Clinical and Laboratory Standards Institute (CLSI, formerly NCCLS. The most active antibiotics for B. fragilis and non- B. fragilis species throughout the three periods were: imipenem with 99.1 and 100% of activity, respectively, and metronidazole with 100% of activity. The susceptibility to ampicillin-sulbactam showed a decrease, from 100% to 90.3% and to 82.4 % in the last period, for both B. fragilis and non-B. fragilis species, respectively. The overall susceptibility rates for cefoxitin, piperacillin, and clindamycin were significantly different between B. fragilis and non-B. fragilis species (84.2% vs. 56.5%; 85.9% vs. 66.7% and 88.8% vs. 64.7%, respectively, pEl objetivo de este estudio fue evaluar las variaciones en el perfil de sensibilidad frente a siete antimicrobianos de aislamientos del grupo Bacteroides fragilis, mediante el análisis de tres relevamientos realizados por la Subcomisión de Bacterias Anaerobias de la Asociación Argentina de Microbiología (años 1989-1991, 1996-1998 y 1999-2002. En los citados períodos se recolectaron 53, 82 y 65 aislamientos del grupo B. fragilis. Se evaluó la actividad de: ampicilina, ampicilina-sulbactama (2:1, cefoxitina, piperacilina, imipenem, clindamicina y metronidazol. La concentración inhibitoria mínima (CIM se determinó utilizando el método de dilución en agar, según las normas del Clinical and Laboratory

  10. Possible misidentification of Bacteroides sp., probably B. ureolyticus as Taylorella equigenitalis: implications for the laboratory diagnosis of CEM.

    Science.gov (United States)

    Moore, J E; Millar, B C; Xu, J; Buckley, T C

    2001-01-01

    A wild-type isolate with similar morphological and phenotypic properties to Taylorella equigenitalis, the causative bacterial agent of contagious equine metritis (CEM), was referred for molecular identification by PCR amplification of the 16S rRNA gene. A species-specific PCR failed to yield a product compatible with that of T. equigenitalis. The direct sequencing of the universal 16S rRNA PCR amplicon suggested the presence of a Bacteroides sp., probably Bacteroides ureolyticus, with no consequent effects on the movement and transportation of the animal. Adoption of such a molecular means of identification through sequencing may aid in the identification of the atypical forms of Taylorella equigenitalis, as recently described, as well as differentiating this species from Taylorella asinigenitalis.

  11. Identification of antimicrobial resistance genes in multidrug-resistant clinical Bacteroides fragilis isolates by whole genome shotgun sequencing

    DEFF Research Database (Denmark)

    Sydenham, Thomas Vognbjerg; Sóki, József; Hasman, Henrik

    2015-01-01

    Bacteroides fragilis constitutes the most frequent anaerobic bacterium causing bacteremia in humans. The genetic background for antimicrobial resistance in B. fragilis is diverse with some genes requiring insertion sequence (IS) elements inserted upstream for increased expression. To evaluate whole...... genome shotgun sequencing as a method for predicting antimicrobial resistance properties, one meropenem resistant and five multidrug-resistant blood culture isolates were sequenced and antimicrobial resistance genes and IS elements identified using ResFinder 2.1 (http...

  12. Simultaneous Detection of Bacteroides forsythus and Prevotella intermedia by 16S rRNA Gene-Directed Multiplex PCR

    Science.gov (United States)

    Conrads, Georg; Flemmig, Thomas F.; Seyfarth, Ilse; Lampert, Friedrich; Lütticken, Rudolf

    1999-01-01

    In a 16S rRNA gene-directed multiplex PCR, Prevotella intermedia- and Bacteroides forsythus-specific reverse primers were combined with a single conserved forward primer. A 660-bp fragment and an 840-bp fragment that were specific for both species could be amplified simultaneously. A total of 152 clinical samples, subgingival plaque and swabs of three different oral mucosae, from 38 periodontitis patients were used for the evaluation. PMID:10203541

  13. Two new xylanases with different substrate specificities from the human gut bacterium Bacteroides intestinalis DSM 17393.

    Science.gov (United States)

    Hong, Pei-Ying; Iakiviak, Michael; Dodd, Dylan; Zhang, Meiling; Mackie, Roderick I; Cann, Isaac

    2014-04-01

    Xylan is an abundant plant cell wall polysaccharide and is a dominant component of dietary fiber. Bacteria in the distal human gastrointestinal tract produce xylanase enzymes to initiate the degradation of this complex heteropolymer. These xylanases typically derive from glycoside hydrolase (GH) families 10 and 11; however, analysis of the genome sequence of the xylan-degrading human gut bacterium Bacteroides intestinalis DSM 17393 revealed the presence of two putative GH8 xylanases. In the current study, we demonstrate that the two genes encode enzymes that differ in activity. The xyn8A gene encodes an endoxylanase (Xyn8A), and rex8A encodes a reducing-end xylose-releasing exo-oligoxylanase (Rex8A). Xyn8A hydrolyzed both xylopentaose (X5) and xylohexaose (X6) to a mixture of xylobiose (X2) and xylotriose (X3), while Rex8A hydrolyzed X3 through X6 to a mixture of xylose (X1) and X2. Moreover, rex8A is located downstream of a GH3 gene (xyl3A) that was demonstrated to exhibit β-xylosidase activity and would be able to further hydrolyze X2 to X1. Mutational analyses of putative active site residues of both Xyn8A and Rex8A confirm their importance in catalysis by these enzymes. Recent genome sequences of gut bacteria reveal an increase in GH8 Rex enzymes, especially among the Bacteroidetes, indicating that these genes contribute to xylan utilization in the human gut.

  14. Assessment of swine-specific bacteriophages of Bacteroides fragilis in swine farms with different antibiotic practices.

    Science.gov (United States)

    Leknoi, Yuranan; Mongkolsuk, Skorn; Sirikanchana, Kwanrawee

    2017-04-01

    We assessed the occurrence and specificity of bacteriophages of Bacteroides fragilis in swine farms for their potential application in microbial source tracking. A local B. fragilis host strain, SP25 (DSM29413), was isolated from a pooled swine feces sample taken from a non-antibiotic farm. This strain was highly specific to swine fecal materials because it did not detect bacteriophages in any samples from human sewage, sheep, goats, cattle, dogs, and cats. The reference B. fragilis strain, RYC2056, could detect phages in swine samples but also detected phages in most human sewage and polluted urban canal samples. Phages of SP25 exist in the proximity of certain swine farms, regardless of their antibiotic use (p > 0.05). B. fragilis strain SP25 exhibited relatively high resistance to most of the veterinary antimicrobial agents tested. Interestingly, most farms that were positive for SP25 phages were also positive for RYC2056 phages. In conclusion, the swine-specific SP25 strain has the potential to indicate swine fecal contamination in certain bodies of water. Bacterial isolates with larger distributions are being studied and validated. This study highlights the importance of assessing the abundance of phages in local swine populations before determining their potential applicability for source tracking in local surface waters.

  15. Enterotoxigenic and non-enterotoxigenic Bacteroides fragilis from fecal microbiota of children

    Directory of Open Access Journals (Sweden)

    Aline Ignacio

    2015-01-01

    Full Text Available Enterotoxigenic Bacteroides fragilis (ETBF is an important part of the human and animal intestinal microbiota and is commonly associated with diarrhea. ETBF strains produce an enterotoxin encoded by the bft gene located in the B. fragilispathogenicity island (BfPAI. Non-enterotoxigenic B. fragilis(NTBF strains lack the BfPAI and usually show two different genetic patterns, II and III, based on the absence or presence of a BfPAI-flanking region, respectively. The incidence of ETBF and NTBF strains in fecal samples isolated from children without acute diarrhea or any other intestinal disorders was determined. All 84 fecal samples evaluated were B. fragilis-positive by PCR, four of them harbored the bft gene, 27 contained the NTBF pattern III DNA sequence, and 52 were considered to be NTBF pattern II samples. One sample was positive for both ETBF and NTBF pattern III DNA sequences. All 19 B. fragilis strains isolated by the culture method were bft-negative, 9 belonged to pattern III and 10 to pattern II. We present an updated overview of the ETBF and NTBF incidence in the fecal microbiota of children from Sao Paulo City, Brazil.

  16. Two New Xylanases with Different Substrate Specificities from the Human Gut Bacterium Bacteroides intestinalis DSM 17393

    KAUST Repository

    Hong, Pei-Ying

    2014-01-24

    Xylan is an abundant plant cell wall polysaccharide and is a dominant component of dietary fiber. Bacteria in the distal human gastrointestinal tract produce xylanase enzymes to initiate the degradation of this complex heteropolymer. These xylanases typically derive from glycoside hydrolase (GH) families 10 and 11; however, analysis of the genome sequence of the xylan-degrading human gut bacterium Bacteroides intestinalis DSM 17393 revealed the presence of two putative GH8 xylanases. In the current study, we demonstrate that the two genes encode enzymes that differ in activity. The xyn8A gene encodes an endoxylanase (Xyn8A), and rex8A encodes a reducing-end xylose-releasing exo-oligoxylanase (Rex8A). Xyn8A hydrolyzed both xylopentaose (X5) and xylohexaose (X6) to a mixture of xylobiose (X2) and xylotriose (X3), while Rex8A hydrolyzed X3 through X6 to a mixture of xylose (X1) and X2. Moreover, rex8A is located downstream of a GH3 gene (xyl3A) that was demonstrated to exhibit β-xylosidase activity and would be able to further hydrolyze X2 to X1. Mutational analyses of putative active site residues of both Xyn8A and Rex8A confirm their importance in catalysis by these enzymes. Recent genome sequences of gut bacteria reveal an increase in GH8 Rex enzymes, especially among the Bacteroidetes, indicating that these genes contribute to xylan utilization in the human gut.

  17. Effect of UV irradiation on macromolecular synthesis and colony formation in Bacteroides fragilis

    International Nuclear Information System (INIS)

    Schumann, J.P.; Jones, D.T.; Woods, D.R.

    1984-01-01

    Irradiation of Bacteroides fragilis cells with far-UV light resulted in the immediate degradation of DNA which continued for 40 to 60 min. During the degradation phase, DNA synthesis was decreased but was never totally inhibited. DNA degradation after irradiation was inhibited by chloramphenicol and caffeine. DNA synthesis in irradiated cells was reduced by chloramphenicol but resumed after 100 min. Irradiated cells continued to synthesize DNA for 40 min in the presence of caffeine but then DNA synthesis was completely inhibited and never recovered. RNA and protein synthesis were decreased by UV irradiation and the degree of inhibition was proportional to the UV dose. Colony formation was not affected immediately by UV irradiation and continued for a dose-dependent period before inhibition. There was an inverse relationship between UV dose and inhibition of colony formatiom which occurred sooner in cells irradiated with lower doses of UV light. The characteristics of DNA synthesis in B. fragilis cells after UV irradiation differ from those in wild-type Escherichia coli cells, where DNA synthesis is stopped immediately by UV irradiation, but resemble those in E. coli recA mutant cells where extensive degradation occurs following UV irradiation. (author)

  18. Prevalence and characterization of enterotoxigenic Bacteroides fragilis and toxigenic Clostridium difficile in a Taipei emergency department.

    Science.gov (United States)

    Ji, Dar-Der; Huang, I-Hsiu; Lai, Chao-Chih; Wu, Fang-Tzy; Jiang, Donald Dah-Shyong; Hsu, Bing-Mu; Lin, Wei-Chen

    2017-02-01

    Enterotoxigenic Bacteroides fragilis (ETBF) and toxin-encoding Clostridium difficile (TXCD) are associated with gastroenteritis. Routine anaerobic blood culture for recovery of these anaerobic pathogens is not used for the detection of their toxins, especially for toxin-variant TXCD. The aim of this study was to investigate the prevalence and risk factors of the genotypes of these anaerobes in patients with acute diarrheal illnesses. The data and samples of 513 patients with gastroenteritis were collected in a Taipei emergency department from March 1, 2006 to December 31, 2009. Nonenterotoxigenic B. fragilis (NTBF) and ETBF and the toxin genotypes of TXCD were detected by molecular methods. The prevalence rates of NTBF, ETBF, and TXCD infections were 33.14%, 1.56%, and 2.34%, respectively. ETBF infections often occurred in the elderly (average age = 67.13 years) and during the cold, dry winters. TXCD infections were widely distributed in age and often occurred in the warm, wet springs and summers. The symptoms of ETBF-infected patients were significantly more severe than those of NTBF-infected patients. This study identified and analyzed the prevalence, risk factors, and clinical presentations of these anaerobic infections. Future epidemiologic and clinical studies are needed to understand the role of ETBF and TXCD in human gastroenteritis. Copyright © 2015. Published by Elsevier B.V.

  19. Levan Enhances Associated Growth of Bacteroides, Escherichia, Streptococcus and Faecalibacterium in Fecal Microbiota.

    Directory of Open Access Journals (Sweden)

    Kaarel Adamberg

    Full Text Available The role of dietary fiber in supporting healthy gut microbiota and overall well-being of the host has been revealed in several studies. Here, we show the effect of a bacterial polyfructan levan on the growth dynamics and metabolism of fecal microbiota in vitro by using isothermal microcalorimetry. Eleven fecal samples from healthy donors were incubated in phosphate-buffered defined medium with or without levan supplementation and varying presence of amino acids. The generation of heat, changes in pH and microbiota composition, concentrations of produced and consumed metabolites during the growth were determined. The composition of fecal microbiota and profile of metabolites changed in response to substrate (levan and amino acids availability. The main products of levan metabolism were acetic, lactic, butyric, propionic and succinic acids and carbon dioxide. Associated growth of levan-degrading (e.g. Bacteroides and butyric acid-producing (e.g. Faecalibacterium taxa was observed in levan-supplemented media. The study shows that the capacity of levan and possibly also other dietary fibers/prebiotics to modulate the composition and function of colon microbiota can be predicted by using isothermal microcalorimetry of fecal samples linked to metabolite and consortia analyses.

  20. The dissemination of C10 cysteine protease genes in Bacteroides fragilis by mobile genetic elements

    Directory of Open Access Journals (Sweden)

    Kagawa Todd F

    2010-04-01

    Full Text Available Abstract Background The C10 family of cysteine proteases includes enzymes that contribute to the virulence of bacterial pathogens, such as SpeB in Streptococcus pyogenes. The presence of homologues of cysteine protease genes in human commensal organisms has not been examined. Bacteroides fragilis is a member of the dominant Bacteroidetes phylum of the human intestinal microbiota, and is a significant opportunistic pathogen. Results Four homologues of the streptococcal virulence factor SpeB were identified in the B. fragilis genome. These four protease genes, two were directly contiguous to open reading frames predicted to encode staphostatin-like inhibitors, with which the protease genes were co-transcribed. Two of these protease genes are unique to B. fragilis 638R and are associated with two large genomic insertions. Gene annotation indicated that one of these insertions was a conjugative Tn-like element and the other was a prophage-like element, which was shown to be capable of excision. Homologues of the B. fragilis C10 protease genes were present in a panel of clinical isolates, and in DNA extracted from normal human faecal microbiota. Conclusions This study suggests a mechanism for the evolution and dissemination of an important class of protease in major members of the normal human microbiota.

  1. Studies of antibiotic resistant mutants of Bacteroides fragilis obtained by Cs-137 ionizing radiation

    International Nuclear Information System (INIS)

    Azghani, A.O.

    1986-01-01

    The genus Bacteroides is an obligate anaerobic bacillus normally found in the upper respiratory tract, the colon, and the genitourinary system. The project reported here was undertaken because of the high frequency of hospital infections attributed to B. fragilis, and the increased resistance of the bacteria to commonly used antibiotics. Cs-137 gamma irradiation was used to induce antibiotic resistant mutants in B. fragilis in the presence of Escherichia coli B/r membrane fragments, employed as reducing agent. Based on a dose-survival curve, an effective radiation dose of 1.54 x 10 4 R (3.99 C/Kg) was used to induce mutations to rifampicin and tetracycline resistance in the test organism. The antibiotic resistant mutants of B. fragilis were utilized to reveal the mechanism by which this group of organisms becomes resistant to select chemotherapeutic agents. Studies on tetracycline resistant mutants of B. fragilis isolated after irradiation, suggest that the resistance to this antibiotic is associated with the outer membrane permeability. The difference in inhibitory action of rifampicin on RNA polymerase activity, from rifampicin sensitive and resistant strains of B. fragilis, reveals that this enzyme is a possible suitable target for inhibition of bacterial growth in anaerobes by rifampicin

  2. Effect of low fluencies of near-ultraviolet radiation on Bacteroides fragilis survival

    International Nuclear Information System (INIS)

    Slade, H.J.K.; Jones, D.T.; Woods, D.R.

    1982-01-01

    Bacteroides fragilis is a convenient obligate anaerobe for an investigation on the effect of near-UV irradiation since the authors have shown that it can be maintained in aerobic solutions for at least 6 h without loss in viability. Furthermore, they recently demonstrated that B. fragilis differs from other bacteria in that it is more sensitive to far-UV (254 nm) radiation in the presence of oxygen. The role of oxygen on near-UV survival in B. fragilis, was investigated. The effect of chloramphenicol was also studied. Survival curves are presented. B. fragilis Bf-2 cells irradiated with increasing fluencies of near-UV light under anaerobic conditions showed no loss in viability. A 'V'-shaped survival curve was obtained when cells were irradiated aerobically. After the initial reduction in viability with fluencies up to 1.5 kJ/m 2 further irradiation resulted in the recovery of colony-forming ability which was maximal at 2.6 kJ/m 2 and remained at this level up to fluencies of 4 kJ/m 2 . (Auth.)

  3. The dissemination of C10 cysteine protease genes in Bacteroides fragilis by mobile genetic elements

    LENUS (Irish Health Repository)

    Thornton, Roibeard F

    2010-04-23

    Abstract Background The C10 family of cysteine proteases includes enzymes that contribute to the virulence of bacterial pathogens, such as SpeB in Streptococcus pyogenes. The presence of homologues of cysteine protease genes in human commensal organisms has not been examined. Bacteroides fragilis is a member of the dominant Bacteroidetes phylum of the human intestinal microbiota, and is a significant opportunistic pathogen. Results Four homologues of the streptococcal virulence factor SpeB were identified in the B. fragilis genome. These four protease genes, two were directly contiguous to open reading frames predicted to encode staphostatin-like inhibitors, with which the protease genes were co-transcribed. Two of these protease genes are unique to B. fragilis 638R and are associated with two large genomic insertions. Gene annotation indicated that one of these insertions was a conjugative Tn-like element and the other was a prophage-like element, which was shown to be capable of excision. Homologues of the B. fragilis C10 protease genes were present in a panel of clinical isolates, and in DNA extracted from normal human faecal microbiota. Conclusions This study suggests a mechanism for the evolution and dissemination of an important class of protease in major members of the normal human microbiota.

  4. RNA-Seq and microarrays analyses reveal global differential transcriptomes of Mesorhizobium huakuii 7653R between bacteroids and free-living cells.

    Directory of Open Access Journals (Sweden)

    Jieli Peng

    Full Text Available Mesorhizobium huakuii 7653R occurs either in nitrogen-fixing symbiosis with its host plant, Astragalus sinicus, or free-living in the soil. The M. huakuii 7653R genome has recently been sequenced. To better understand the complex biochemical and developmental changes that occur in 7653R during bacteroid development, RNA-Seq and Microarrays were used to investigate the differential transcriptomes of 7653R bacteroids and free-living cells. The two approaches identified several thousand differentially expressed genes. The most prominent up-regulation occurred in the symbiosis plasmids, meanwhile gene expression is concentrated to a set of genes (clusters in bacteroids to fulfill corresponding functional requirements. The results suggested that the main energy metabolism is active while fatty acid metabolism is inactive in bacteroid and that most of genes relevant to cell cycle are down-regulated accordingly. For a global analysis, we reconstructed a protein-protein interaction (PPI network for 7653R and integrated gene expression data into the network using Cytoscape. A highly inter-connected subnetwork, with function enrichment for nitrogen fixation, was found, and a set of hubs and previously uncharacterized genes participating in nitrogen fixation were identified. The results described here provide a broader biological landscape and novel insights that elucidate rhizobial bacteroid differentiation, nitrogen fixation and related novel gene functions.

  5. Specific cell components of Bacteroides gingivalis mediate binding and degradation of human fibrinogen

    Energy Technology Data Exchange (ETDEWEB)

    Lantz, M.S.; Allen, R.D.; Vail, T.A.; Switalski, L.M.; Hook, M. (Univ. of Alabama at Birmingham (USA))

    1991-01-01

    Bacteroides (Porphyromonas) gingivalis, which has been implicated as an etiologic agent in human periodontal diseases, has been shown to bind and degrade human fibrinogen. B. gingivalis strains bind fibrinogen reversibly and with high affinity and bind to a specific region of the fibrinogen molecule that appears to be located between the D and E domains. The authors now report that human fibrinogen is bound and then degraded by specific B. gingivalis components that appear to be localized at the cell surface. Fibrinogen binding to bacterial cells occurred at 4, 22, and 37{degree}C. A functional fibrinogen-binding component (M{sub r}, 150 000) was identified when sodium dodecyl sulfate-solubilized bacteria were fractionated by sodium dodecyl sulfate-polyacrylamide gel electrophoresis, transferred to nitrocellulose membranes, and probed with {sup 125}I-fibrinogen. Fibrinogen degradation did not occur at 4{degree}C but did occur at 22 and 37{degree}C. When bacteria and iodinated fibrinogen were incubated at 37{degree}C, two major fibrinogen fragments (M{sub r}, 97 000 and 50 000) accumulated in incubation mixture supernatant fractions. Two major fibrinogen-degrading components (M{sub r}, 120 000 and 150 000) have been identified by sodium dodecyl sulfate-polyacrylamide gel electrophoresis in substrate-containing gels. Fibrinogen degradation by the M{sub r}-120 000 and -150 000 proteases was enhanced by reducing agents, completely inhibited by N-{alpha}-p-tosyl-L-lysyl chloromethyl ketone, and partially inhibited by n-ethyl maleimide, suggesting that these enzymes are thiol-dependent proteases with trypsinlike substrate specificity. The fibrinogen-binding component could be separated from the fibrinogen-degrading components by selective solubilization of bacteria in sodium deoxycholate.

  6. Bacteroides gingivalis antigens and bone resorbing activity in root surface fractions of periodontally involved teeth

    International Nuclear Information System (INIS)

    Patters, M.R.; Landsberg, R.L.; Johansson, L.-A.; Trummel, C.L.; Robertson, P.R.

    1982-01-01

    Bone resorbing activity and the presence of antigens of Bacteroides gingivalis were assessed in plaque, calculus, cementum, and dentin obtained from roots of teeth previously exposed to periodontitis. Each fraction was obtained by scaling the root surface. The fraction were extracted by stirring and sonication, and the soluble centrifuged, sterilized, dialyzed, and adjusted to equivalent protein concentrations. Cementum and dentin extracts from impacted teeth were prepared similarly and served as controls. Stimulation of bone resorption by each extract was assessed in organ cultures of fetal rat bones by measurement of release of previously-incorporated 45 Ca from the bone into the medium. In some groups of teeth, calculus and cementum were treated with acid prior to scaling. Citric acid washes were recovered and dialyzed. An enzyme-linked immunosorbent assay (ELISA) was used to assess the extracts for the presence of antigens reactive with an antiserum to B. gingivalis. Significant stimulation of bone resorption was found in all calculus and periodontally-involved cementum preparations. ELISA showed significant levels of B.gingivalis antigens in plaque, calculus, and cementum of periodontally-involved teeth, but not in involved dentin nor in cementum or dentin of impact teeth. Treatment with citric acid removed essentially all B.gingivalis antigens from cementum but not calculus. The results suggest that substances which stimulate bone resorption and substances which react with B. gingivalis antiserum are present in surface plaque, calculus, and cementum or periodontally-involved teeth. These substances are not present in cementum and dentin of impacted teeth nor in dentin of periodontally-involved teeth. Treatment by both scaling and citric demineralization will remove most of these substances from cementum of teeth previously exposed to periodontitis. (author)

  7. Bacteroides gingivalis antigens and bone resorbing activity in root surface fractions of periodontally involved teeth

    Energy Technology Data Exchange (ETDEWEB)

    Patters, M.R.; Landsberg, R.L.; Johansson, L.A.; Trummel, C.L.; Robertson, P.R. (Department of Periodontology, University of Connecticut, School of Dental Medicine, Farmington, Connecticut, U.S.A.)

    1982-01-01

    Bone resorbing activity and the presence of antigens of Bacteroides gingivalis were assessed in plaque, calculus, cementum, and dentin obtained from roots of teeth previously exposed to periodontitis. Each fraction was obtained by scaling the root surface. The fraction were extracted by stirring and sonication, and the soluble centrifuged, sterilized, dialyzed, and adjusted to equivalent protein concentrations. Cementum and dentin extracts from impacted teeth were prepared similarly and served as controls. Stimulation of bone resorption by each extract was assessed in organ cultures of fetal rat bones by measurement of release of previously-incorporated /sup 45/Ca from the bone into the medium. In some groups of teeth, calculus and cementum were treated with acid prior to scaling. Citric acid washes were recovered and dialyzed. An enzyme-linked immunosorbent assay (ELISA) was used to assess the extracts for the presence of antigens reactive with an antiserum to B. gingivalis. Significant stimulation of bone resorption was found in all calculus and periodontally-involved cementum preparations. ELISA showed significant levels of B.gingivalis antigens in plaque, calculus, and cementum of periodontally-involved teeth, but not in involved dentin nor in cementum or dentin of impact teeth. Treatment with citric acid removed essentially all B.gingivalis antigens from cementum but not calculus. The results suggest that substances which stimulate bone resorption and substances which react with B. gingivalis antiserum are present in surface plaque, calculus, and cementum or periodontally-involved teeth. These substances are not present in cementum and dentin of impacted teeth nor in dentin of periodontally-involved teeth. Treatment by both scaling and citric demineralization will remove most of these substances from cementum of teeth previously exposed to periodontitis.

  8. Human Bacteroides and total coliforms as indicators of recent combined sewer overflows and rain events in urban creeks

    Science.gov (United States)

    McGinnis, Shannon; Spencer, Susan K.; Firnstahl, Aaron; Stokdyk, Joel; Borchardt, Mark A.; McCarthy, David; Murphy, Heather

    2018-01-01

    Combined sewer overflows (CSOs) are a known source of human fecal pollution and human pathogens in urban water bodies, which may present a significant public health threat. To monitor human fecal contamination in water, bacterial fecal indicator organisms (FIOs) are traditionally used. However, because FIOs are not specific to human sources and do not correlate with human pathogens, alternative fecal indicators detected using qPCR are becoming of interest to policymakers. For this reason, this study measured correlations between the number and duration of CSOs and mm of rainfall, concentrations of traditional FIOs and alternative indicators, and the presence of human pathogens in two urban creeks. Samples were collected May–July 2016 and analyzed for concentrations of FIOs (total coliforms and E. coli) using membrane filtration as well as for three alternative fecal indicators (human Bacteroides HF183 marker, human polyomavirus (HPoV), pepper mild mottle virus (PMMoV)) and nine human pathogens using qPCR. Four of the nine pathogens analyzed were detected at these sites including adenovirus, Enterohemorrhagic E. coli, norovirus, and Salmonella. Among all indicators studied, human Bacteroides and total coliforms were significantly correlated with recent CSO and rainfall events, while E. coli, PMMoV, and HPoV did not show consistent significant correlations. Further, human Bacteroides were a more specific indicator, while total coliforms were a more sensitive indicator of CSO and rainfall events. Results may have implications for the use and interpretation of these indicators in future policy or monitoring programs.

  9. Bacteroides CECT 7771 y su uso en la prevención y tratamiento de sobrepeso, obesidad y alteraciones metabólicas e inmunológicas

    OpenAIRE

    Sanz Herranz, Yolanda; Gauffin, Paola; Santacruz, Arlette; Moya Pérez, Ángela; Laparra, José Moisés

    2012-01-01

    Bacteroides CECT 7771 y su uso en la prevención y tratamiento de sobrepeso, obesidad y alteraciones metabólicas e inmunológicas. La presente invención se refiere a una cepa de Bacteroides uniformis con número de depósito CECT 7771, así como a sus componentes celulares, metabolitos y/o moléculas secretadas. Es también objeto de la invención, una composición (nutritiva o farmacéutica) que comprende al menos uno de los productos anteriores. Asimismo, la presente inv...

  10. The underappreciated in vitro activity of tedizolid against Bacteroides fragilis species, including strains resistant to metronidazole and carbapenems.

    Science.gov (United States)

    Goldstein, Ellie J C; Citron, Diane M; Tyrrell, Kerin L; Leoncio, Elisa S; Merriam, C Vreni

    2017-02-01

    Because Bacteroides fragilis has the ability to develop mechanisms of resistance to almost all antibiotics, we studied the comparative in vitro activity of tedizolid against 124 Bacteroides group species clinical isolates, including carbapenem, metronidazole and piperacillin-tazobactam resistant strains. Tedizolid had an MIC 90 of 2 μg/ml (range, 0.5-4 μg/ml) and was 1-4 times more active than linezolid that had an MIC 90 of 8 μg/ml (range, 2-16 μg/ml). It was also active (MICs 0.5-2 μg/ml) against the 27 ertapenem, 2 metronidazole and 12 piperacillin-tazobactam resistant strains tested. This suggests that tedizolid may be useful treating infections, including bacteremias, due to resistant B. fragilis group species, as well as, mixed skin and soft tissue infections such as diabetic foot infections caused by Gram-positive aerobes and B. fragilis group species. Copyright © 2016 Elsevier Ltd. All rights reserved.

  11. Bacteroides intestinalis DSM 17393, a member of the human colonic microbiome, upregulates multiple endoxylanases during growth on xylan.

    Science.gov (United States)

    Wang, Kui; Pereira, Gabriel V; Cavalcante, Janaina J V; Zhang, Meiling; Mackie, Roderick; Cann, Isaac

    2016-09-29

    Many human diets contain arabinoxylan, and the ease of genome sequencing coupled with reduced cost have led to unraveling the arsenal of genes utilized by the colonic Bacteroidetes to depolymerize this polysaccharide. The colonic Bacteroidetes with potential to ferment arabinoxylans include Bacteroides intestinalis. In this study, we analyzed the hydrolytic activities of members of a xylan degradation cluster encoded on the genome of Bacteroides intestinalis DSM 17393. Here, it is demonstrated that a cocktail of the xylanolytic enzymes completely hydrolyze arabinoxylans found in human diets. We show that this bacterium and relatives have evolved and secrete a unique bifunctional endoxylanase/arabinofuranosidase in the same polypeptide. The bifunctional enzyme and other secreted enzymes attack the polysaccharides extracellularly to remove the side-chains, exposing the xylan backbone for cleavage to xylo-oligosaccharides and xylose. These end products are transported into the cell where a β-xylosidase cleaves the oligosaccharides to fermentable sugars. While our experiments focused on B. intestinalis, it is likely that the extracellular enzymes also release nutrients to members of the colonic microbial community that practice cross-feeding. The presence of the genes characterized in this study in other colonic Bacteroidetes suggests a conserved strategy for energy acquisition from arabinoxylan, a component of human diets.

  12. Ethnic diversity of gut microbiota: species characterization of Bacteroides fragilis group and genus Bifidobacterium in healthy Belgian adults, and comparison with data from Japanese subjects.

    Science.gov (United States)

    Ishikawa, Eiji; Matsuki, Takahiro; Kubota, Hiroyuki; Makino, Hiroshi; Sakai, Takafumi; Oishi, Kenji; Kushiro, Akira; Fujimoto, Junji; Watanabe, Koichi; Watanuki, Masaaki; Tanaka, Ryuichiro

    2013-08-01

    The composition of the human gut microbiota is related to host health, and it is thought that dietary habits may play a role in shaping this composition. Here, we examined the population size and prevalence of six predominant bacterial genera and the species compositions of genus Bifidobacterium (g-Bifid) and Bacteroides fragilis group (g-Bfra) in 42 healthy Belgian adults by quantitative PCR (qPCR) over a period of one month. The population sizes and prevalence of these bacteria were basically stable throughout the study period. The predominant g-Bifid species were Bifidobacterium adolescentis and Bifidobacterium longum ss. longum, and the predominant g-Bfra species were Bacteroides vulgatus, Bacteroides uniformis, and Bacteroides ovatus. The Belgian gut microbiota data were then compared with gut microbiota data from 46 Japanese subjects collected according to the same protocol (Matsuki et al., Appl. Environ. Microbiol. 70, 167-173, 2004). The population size and prevalence of Bifidobacterium catenulatum group were significantly lower in the Belgian gut microbiota than in the Japanese gut microbiota (P diversity of gut microbiota among ethnic groups. Copyright © 2013 The Society for Biotechnology, Japan. Published by Elsevier B.V. All rights reserved.

  13. First report of metronidazole resistant, nimD-positive, Bacteroides stercoris isolated from an abdominal abscess in a 70-year-old woman

    DEFF Research Database (Denmark)

    Otte, Erik; Nielsen, Hans Linde; Hasman, Henrik

    2017-01-01

    We here present the first case of a metronidazole resistant nimD positive Bacteroides stercoris. The isolate originated from a polymicrobial intra-abdominal abscess in a 70-year-old woman. The nimD gene was detected by use of whole-genome shotgun sequencing and the subsequent use of the ResFinder 2...

  14. High-resolution transcriptomic analyses of Sinorhizobium sp. NGR234 bacteroids in determinate nodules of Vigna unguiculata and indeterminate nodules of Leucaena leucocephala.

    Science.gov (United States)

    Li, Yan; Tian, Chang Fu; Chen, Wen Feng; Wang, Lei; Sui, Xin Hua; Chen, Wen Xin

    2013-01-01

    The rhizobium-legume symbiosis is a model system for studying mutualistic interactions between bacteria and eukaryotes. Sinorhizobium sp. NGR234 is distinguished by its ability to form either indeterminate nodules or determinate nodules with diverse legumes. Here, we presented a high-resolution RNA-seq transcriptomic analysis of NGR234 bacteroids in indeterminate nodules of Leucaena leucocephala and determinate nodules of Vigna unguiculata. In contrast to exponentially growing free-living bacteria, non-growing bacteroids from both legumes recruited several common cellular functions such as cbb3 oxidase, thiamine biosynthesis, nitrate reduction pathway (NO-producing), succinate metabolism, PHB (poly-3-hydroxybutyrate) biosynthesis and phosphate/phosphonate transporters. However, different transcription profiles between bacteroids from two legumes were also uncovered for genes involved in the biosynthesis of exopolysaccharides, lipopolysaccharides, T3SS (type three secretion system) and effector proteins, cytochrome bd ubiquinol oxidase, PQQ (pyrroloquinoline quinone), cytochrome c550, pseudoazurin, biotin, phasins and glycolate oxidase, and in the metabolism of glutamate and phenylalanine. Noteworthy were the distinct expression patterns of genes encoding phasins, which are thought to be involved in regulating the surface/volume ratio of PHB granules. These patterns are in good agreement with the observed granule size difference between bacteroids from L. leucocephala and V. unguiculata.

  15. High-resolution transcriptomic analyses of Sinorhizobium sp. NGR234 bacteroids in determinate nodules of Vigna unguiculata and indeterminate nodules of Leucaena leucocephala.

    Directory of Open Access Journals (Sweden)

    Yan Li

    Full Text Available The rhizobium-legume symbiosis is a model system for studying mutualistic interactions between bacteria and eukaryotes. Sinorhizobium sp. NGR234 is distinguished by its ability to form either indeterminate nodules or determinate nodules with diverse legumes. Here, we presented a high-resolution RNA-seq transcriptomic analysis of NGR234 bacteroids in indeterminate nodules of Leucaena leucocephala and determinate nodules of Vigna unguiculata. In contrast to exponentially growing free-living bacteria, non-growing bacteroids from both legumes recruited several common cellular functions such as cbb3 oxidase, thiamine biosynthesis, nitrate reduction pathway (NO-producing, succinate metabolism, PHB (poly-3-hydroxybutyrate biosynthesis and phosphate/phosphonate transporters. However, different transcription profiles between bacteroids from two legumes were also uncovered for genes involved in the biosynthesis of exopolysaccharides, lipopolysaccharides, T3SS (type three secretion system and effector proteins, cytochrome bd ubiquinol oxidase, PQQ (pyrroloquinoline quinone, cytochrome c550, pseudoazurin, biotin, phasins and glycolate oxidase, and in the metabolism of glutamate and phenylalanine. Noteworthy were the distinct expression patterns of genes encoding phasins, which are thought to be involved in regulating the surface/volume ratio of PHB granules. These patterns are in good agreement with the observed granule size difference between bacteroids from L. leucocephala and V. unguiculata.

  16. Current Status of Marker Genes of Bacteroides and Related Taxa for Identifying Sewage Pollution in Environmental Waters

    Directory of Open Access Journals (Sweden)

    Warish Ahmed

    2016-05-01

    Full Text Available Microbial source tracking (MST endeavors to determine sources of fecal pollution in environmental waters by capitalizing on the association of certain microorganisms with the gastrointestinal tract and feces of specific animal groups. Several decades of research have shown that bacteria belonging to the gut-associated order Bacteroidales, and particularly the genus Bacteroides, tend to co-evolve with the host, and are, therefore, particularly suitable candidates for MST applications. This review summarizes the current research on MST methods that employ genes belonging to Bacteroidales/Bacteroides as tracers or “markers” of sewage pollution, including known advantages and deficiencies of the many polymerase chain reaction (PCR-based methods that have been published since 2000. Host specificity is a paramount criterion for confidence that detection of a marker is a true indicator of the target host. Host sensitivity, or the prevalence of the marker in feces/waste from the target host, is necessary for confidence that absence of the marker is indicative of the absence of the pollution source. Each of these parameters can vary widely depending on the type of waste assessed and the geographic location. Differential decay characteristics of bacterial targets and their associated DNA contribute to challenges in interpreting MST results in the context of human health risks. The HF183 marker, derived from the 16S rRNA gene of Bacteroides dorei and closely related taxa, has been used for almost two decades in MST studies, and is well characterized regarding host sensitivity and specificity, and in prevalence and concentration in sewage in many countries. Other markers such as HumM2 and HumM3 show promise, but require further performance testing to demonstrate their widespread utility. An important limitation of the one-marker-one-assay approach commonly used for MST is that given the complexities of microbial persistence in environmental waters, and

  17. Prevalence of antimicrobial resistance and the cfiA resistance gene in Danish Bacteroides fragilis group isolates since 1973

    DEFF Research Database (Denmark)

    Ferløv-Schwensen, Simon Andreas; Sydenham, Thomas Vognbjerg; Hansen, Kia Cirkeline Møller

    2017-01-01

    .0%) B. fragilis strains as division II, of which 4 strains, isolated between 2010 and 2015, were resistant to meropenem. CONCLUSIONS: Substantial increases in resistance were found throughout this study. This supports the general perception that antimicrobial resistance in the B. fragilis group has been......OBJECTIVES: The purpose of this study was to determine the prevalence of resistance and the cfiA carbapenemase-producing gene in historical Bacteroides fragilis group isolates. METHODS: Danish clinical B. fragilis group isolates (n = 444) from 1973 to 2015 were identified with Matrix-Assisted Laser...... Desorption/Ionization Time-Of-Flight Mass Spectrometry (MALDI-TOF MS) on the Biotyper platform. Antimicrobial resistance was determined using a disk diffusion screening method and commercial antibiotic gradient strips. Division I (cfiA-negative) and division II (cfiA-positive) B. fragilis strains were...

  18. Twenty-eight divergent polysaccharide loci specifying within and amongst strain capsule diversity in three strains of Bacteroides fragilis

    DEFF Research Database (Denmark)

    Patrick, S.; Blakely, G.W.; Houston, S.

    2010-01-01

    Comparison of the complete genome sequence of Bacteroides fragilis 638R originally isolated in the USA, was made with two previously sequenced strains isolated in the UK (NCTC 9343) and Japan (YCH46). The presence of 10 loci containing genes associated with polysaccharide biosynthesis, each...... including a putative Wzx flippase and Wzy polymerase, was confirmed in all three strains, despite a lack of cross-reactivity between NCTC 9343 and 638R surface polysaccharide-specific antibodies by immunolabelling and microscopy. Genomic comparisons revealed an exceptional level of polysaccharide...... biosynthesis locus diversity. Of the 10 divergent polysaccharide associated loci apparent in each strain, none are similar between NCTC9343 and 638R. YCH46 shares one locus with NCTC9343, confirmed by MAb labelling, and a second different locus with 638R, making a total of 28 divergent polysaccharide...

  19. The structure of BVU2987 from Bacteroides vulgatus reveals a superfamily of bacterial periplasmic proteins with possible inhibitory function

    International Nuclear Information System (INIS)

    Das, Debanu; Finn, Robert D.; Carlton, Dennis; Miller, Mitchell D.; Abdubek, Polat; Astakhova, Tamara; Axelrod, Herbert L.; Bakolitsa, Constantina; Chen, Connie; Chiu, Hsiu-Ju; Chiu, Michelle; Clayton, Thomas; Deller, Marc C.; Duan, Lian; Ellrott, Kyle; Ernst, Dustin; Farr, Carol L.; Feuerhelm, Julie; Grant, Joanna C.; Grzechnik, Anna; Han, Gye Won; Jaroszewski, Lukasz; Jin, Kevin K.; Klock, Heath E.; Knuth, Mark W.; Kozbial, Piotr; Krishna, S. Sri; Kumar, Abhinav; Marciano, David; McMullan, Daniel; Morse, Andrew T.; Nigoghossian, Edward; Nopakun, Amanda; Okach, Linda; Puckett, Christina; Reyes, Ron; Rife, Christopher L.; Sefcovic, Natasha; Tien, Henry J.; Trame, Christine B.; Bedem, Henry van den; Weekes, Dana; Wooten, Tiffany; Xu, Qingping; Hodgson, Keith O.; Wooley, John; Elsliger, Marc-André; Deacon, Ashley M.; Godzik, Adam; Lesley, Scott A.; Wilson, Ian A.

    2010-01-01

    The crystal structure of the BVU2987 gene product from B. vulgatus (UniProt A6L4L1) reveals that members of the new Pfam family PF11396 (domain of unknown function; DUF2874) are similar to β-lactamase inhibitor protein and YpmB. Proteins that contain the DUF2874 domain constitute a new Pfam family PF11396. Members of this family have predominantly been identified in microbes found in the human gut and oral cavity. The crystal structure of one member of this family, BVU2987 from Bacteroides vulgatus, has been determined, revealing a β-lactamase inhibitor protein-like structure with a tandem repeat of domains. Sequence analysis and structural comparisons reveal that BVU2987 and other DUF2874 proteins are related to β-lactamase inhibitor protein, PepSY and SmpA-OmlA proteins and hence are likely to function as inhibitory proteins

  20. Overexpression, crystallization and preliminary X-ray crystallographic analysis of a putative xylose isomerase from Bacteroides thetaiotaomicron.

    Science.gov (United States)

    Cho, Jea-Won; Han, Byeong-Gu; Park, Sang Youn; Kim, Seung Jun; Kim, Myoung-Dong; Lee, Byung Il

    2013-10-01

    Bacteroides thetaiotaomicron BT0793, a putative xylose isomerase, was overexpressed in Escherichia coli, purified and crystallized using polyethylene glycol monomethyl ether 550 as the precipitant. X-ray diffraction data were collected to 2.10 Å resolution at 100 K using synchrotron X-rays. The crystal was found to belong to space group P1, with unit-cell parameters a=96.3, b=101.7, c=108.3 Å, α=82.8, β=68.2, γ=83.0°. The asymmetric unit contained eight subunits of xylose isomerase with a crystal volume per protein weight (VM) of 2.38 Å3 Da(-1) and a solvent content of 48.3%.

  1. An overview of the metabolic differences between Bradyrhizobium japonicum 110 bacteria and differentiated bacteroids from soybean (Glycine max) root nodules: an in vitro 13C- and 31P-nuclear magnetic resonance spectroscopy study

    International Nuclear Information System (INIS)

    Vauclare, Pierre; Bligny, Richard; Gout, Elisabeth; Widmer, Francois

    2013-01-01

    Bradyrhizobium japonicum is a symbiotic nitrogen-fixing soil bacteria that induce root nodules formation in legume soybean (Glycine max.). Using 13 C- and 31 P-nuclear magnetic resonance (NMR) spectroscopy, we have analysed the metabolite profiles of cultivated B. japonicum cells and bacteroids isolated from soybean nodules. Our results revealed some quantitative and qualitative differences between the metabolite profiles of bacteroids and their vegetative state. This includes in bacteroids a huge accumulation of soluble carbohydrates such as trehalose, glutamate, myo-inositol and homo-spermidine as well as Pi, nucleotide pools and intermediates of the primary carbon metabolism. Using this novel approach, these data show that most of the compounds detected in bacteroids reflect the metabolic adaptation of rhizobia to the surrounding microenvironment with its host plant cells. (authors)

  2. Purification, crystallization and diffraction studies of the methyltransferases BT-2972 and BVU-3255 from antibiotic-resistant pathogens of the genus Bacteroides from the human intestine

    International Nuclear Information System (INIS)

    Kumar, Veerendra; Mallika, Nagarajan; Sivaraman, J.

    2011-01-01

    The expression, purification, crystallization and diffraction of two methyltransferases BT-2972 and BVU-3255 from two Bacteroides species of antibiotic-resistant pathogens from the human intestine are reported. The methyltransferases BT-2972 and BVU-3255 from two different Bacteroides species that are antibiotic-resistant pathogens from the human intestine were cloned, overexpressed and purified, yielding approximately 120 mg of each protein from 1 l culture. Apo BT-2972 and BVU-3255 and their complexes with S-adenosylmethionine or S-adenosylhomocysteine were crystallized in four different crystal forms using the hanging-drop vapour-diffusion method. These crystals diffracted to resolutions ranging from 2.8 to 2.2 Å. Sequence analysis suggested that the two proteins are homologous small-molecule methyltransferases

  3. Vitamin B12 Uptake by the gut commensal bacteria bacteroides thetaiotaomicron limits the production of shiga toxin by enterohemorrhagic escherichia coli

    OpenAIRE

    Cordonnier, Charlotte; Le Bihan , Guillaume; Emond-Rheault , Jean-Guillaume; Garrivier, Annie; Harel, Josee; Jubelin, Grégory

    2016-01-01

    Enterohemorrhagic Escherichia coli (EHEC) are foodborne pathogens responsible for the development of bloody diarrhea and renal failure in humans. Many environmental factors have been shown to regulate the production of Shiga toxin 2 (Stx2), the main virulence factor of EHEC. Among them, soluble factors produced by human gut microbiota and in particular, by the predominant species Bacteroides thetaiotaomicron (B. thetaiotaomicron), inhibit Stx2 gene expression. In this study, we investigated t...

  4. Characterisation of a multidrug-resistant Bacteroides fragilis isolate recovered from blood of a patient in Denmark using whole-genome sequencing

    DEFF Research Database (Denmark)

    Ank, Nina; Sydenham, Thomas V; Iversen, Lene H

    2015-01-01

    Here we describe a patient undergoing extensive abdominal surgery and hyperthermic intraperitoneal chemotherapy due to primary adenocarcinoma in the sigmoid colon with peritoneal carcinomatosis. During hospitalisation the patient suffered from bacteraemia with a multidrug-resistant Bacteroides fr...... fragilis isolate. Whole-genome sequencing of the isolate resulted in identification of nimE, cfiA and ermF genes corresponding to metronidazole, carbapenem and clindamycin resistance....

  5. Alterations of Bacteroides sp., Neisseria sp., Actinomyces sp., and Streptococcus sp. populations in the oropharyngeal microbiome are associated with liver cirrhosis and pneumonia.

    Science.gov (United States)

    Lu, Haifeng; Qian, Guirong; Ren, Zhigang; Zhang, Chunxia; Zhang, Hua; Xu, Wei; Ye, Ping; Yang, Yunmei; Li, Lanjuan

    2015-06-23

    The microbiomes of humans are associated with liver and lung inflammation. We identified and verified alterations of the oropharyngeal microbiome and assessed their association with cirrhosis and pneumonia. Study components were as follows: (1) determination of the temporal stability of the oropharyngeal microbiome; (2) identification of oropharyngeal microbial variation in 90 subjects; (3) quantitative identification of disease-associated bacteria. DNAs enriched in bacterial sequences were produced from low-biomass oropharyngeal swabs using whole genome amplification and were analyzed using denaturing gradient gel electrophoresis analysis. Whole genome amplification combined with denaturing gradient gel electrophoresis analysis monitored successfully oropharyngeal microbial variations and showed that the composition of each subject's oropharyngeal microbiome remained relatively stable during the follow-up. The microbial composition of cirrhotic patients with pneumonia differed from those of others and clustered together in subgroup analysis. Further, species richness and the value of Shannon's diversity and evenness index increased significantly in patients with cirrhosis and pneumonia versus others (p pneumonia). Moreover, we identified variants of Bacteroides, Eubacterium, Lachnospiraceae, Neisseria, Actinomyces, and Streptococcus through phylogenetic analysis. Quantitative polymerase chain reaction assays revealed that the populations of Bacteroides, Neisseria, and Actinomycetes increased, while that of Streptococcus decreased in cirrhotic patients with pneumonia versus others (p pneumonia). Alterations of Bacteroides, Neisseria, Actinomyces, and Streptococcus populations in the oropharyngeal microbiome were associated with liver cirrhosis and pneumonia.

  6. Suppurative otitis and ascending meningoencephalitis associated with Bacteroides tectus and Porphyromonas gulae in a captive Parma wallaby (Macropus parma) with toxoplasmosis.

    Science.gov (United States)

    Giannitti, Federico; Schapira, Andrea; Anderson, Mark; Clothier, Kristin

    2014-09-01

    A 6-year-old female Parma wallaby (Macropus parma) at a zoo in California developed acute ataxia and left-sided circling. Despite intensive care, clinical signs progressed to incoordination and prostration, and the animal was euthanized. At necropsy, the left tympanic cavity was filled with homogeneous suppurative exudate that extended into the cranium expanding the meninges and neuroparenchyma in the lateral and ventral aspect of the caudal ipsilateral brainstem and medulla oblongata. Microscopically, the brainstem showed regional severe suppurative meningoencephalitis with large numbers of neutrophils, fewer macrophages, and lymphocytes admixed with fibrin, necrotic cellular debris, hemorrhage, and mineralization, with numerous intralesional Gram-negative bacilli. Bacteroides spp. and Porphyromonas spp. were isolated on anaerobic culture from the meninges, and the bacteria were further characterized by partial 16S ribosomal RNA gene sequencing as Bacteroides tectus and Porphyromonas gulae. Bacterial aerobic culture from the meninges yielded very low numbers of mixed flora and Proteus spp., which were considered contaminants. Culture of Mycoplasma spp. from middle ear and meninges was negative. Additionally, Toxoplasma gondii cysts were detected by immunohistochemistry in the heart and brain, and anti-Toxoplasma antibodies were detected in serum. The genera Bacteroides and Porphyromonas have been associated with oral disease in marsupials; but not with otitis and meningoencephalitis. The results of the present work highlight the importance of performing anaerobic cultures in the diagnostic investigation of cases of suppurative otitis and meningoencephalitis in macropods. © 2014 The Author(s).

  7. Distribution and Abundance of Human Specific Bacteroides and Relation to Traditional Indicators in an Urban Tropical Catchment

    Science.gov (United States)

    Nshimyimana, J.; Shanahan, P.; Thompson, J. R.; Ekklesia, E.; Chua Hock Chye, L.

    2012-12-01

    The Singapore government through its Public Utilities Board is interested in opening Kranji Reservoir to recreational use. However, water courses within the Kranji Reservoir catchment contain human fecal indicator bacteria above recreational water quality criteria; their sources and distribution are unknown. The primary goals of this study were to determine the distribution of fecal indicator bacteria in drainages and water bodies in the Kranji reservoir catchment area. Total coliforms, E. coli, and the DNA-based HF marker (targeting a human specific strain of Bacteroides) were quantified in 27 samples collected in January 2009 and 54 samples collected in July 2009. Correlation of HF marker cell equivalents (CE) and E. coli abundance (colony forming units (CFU) or Most Probable Number (MPN)) to different land-use categories revealed potential sources of fecal contamination to the Kranji reservoir. Notably, areas designated as farming/agricultural were associated with the highest levels of E. coli (geometric mean 30,500 CFU/100 ml) and HF marker (1.23±1.13x106 CE/100 ml ± S.D.) while in general lower HF marker and E. coli levels were observed in residential areas, undeveloped areas, and within the Kranji reservoir (i.e. Kranji Reservoir had 2 to 17 MPN/100 ml of E. coli and 103 to 105 HF marker CE/100 ml). A partial survey of potential point sources for fecal contamination within the farming area revealed a wastewater effluent stream with HF marker levels exceeding 107 CE/100ml. As observed in previous studies, total coliforms and E. coli levels were weakly (Rcoliforms) and molecular indicators (HF marker) may be explained by differences in the ability of the respective organisms to grow or survive under aerated tropical conditions. The HF marker sequence matches that of Bacteroides dorei, an obligate anaerobe that is not expected to grow in aerated surface waters. In contrast, numerous studies have demonstrated that total coliforms, including E. coli, are able to

  8. Commensal Bacteroides species induce colitis in host-genotype-specific fashion in a mouse model of inflammatory bowel disease

    Science.gov (United States)

    Bloom, Seth M.; Bijanki, Vinieth N.; Nava, Gerardo M.; Sun, Lulu; Malvin, Nicole P.; Donermeyer, David L.; Dunne, W. Michael; Allen, Paul M.; Stappenbeck, Thaddeus S.

    2011-01-01

    SUMMARY The intestinal microbiota is important for induction of inflammatory bowel disease (IBD). IBD is associated with complex shifts in microbiota composition, but it is unclear whether specific bacterial subsets induce IBD and, if so, whether their proportions in the microbiota are altered during disease. Here we fulfilled Koch’s postulates in host-genotype-specific fashion using a mouse model of IBD with human-relevant disease-susceptibility mutations. From screening experiments we isolated common commensal Bacteroides species, introduced them into antibiotic-pretreated mice, and quantitatively re-isolated them in culture. The bacteria colonized IBD-susceptible and non-susceptible mice equivalently, but induced disease exclusively in susceptible animals. Conversely, commensal Enterobacteriaceae were >100-fold enriched during spontaneous disease but an Enterobacteriaceae isolate failed to induce disease in antibiotic-pretreated mice despite robust colonization. We thus demonstrate that IBD-associated microbiota alterations do not necessarily reflect underlying disease etiology. These findings establish important experimental criteria and a conceptual framework for understanding microbial contributions to IBD. PMID:21575910

  9. Quantitative metabolomics of a xylose-utilizing Saccharomyces cerevisiae strain expressing the Bacteroides thetaiotaomicron xylose isomerase on glucose and xylose.

    Science.gov (United States)

    Mert, M J; Rose, S H; la Grange, D C; Bamba, T; Hasunuma, T; Kondo, A; van Zyl, W H

    2017-10-01

    The yeast Saccharomyces cerevisiae cannot utilize xylose, but the introduction of a xylose isomerase that functions well in yeast will help overcome the limitations of the fungal oxido-reductive pathway. In this study, a diploid S. cerevisiae S288c[2n YMX12] strain was constructed expressing the Bacteroides thetaiotaomicron xylA (XI) and the Scheffersomyces stipitis xyl3 (XK) and the changes in the metabolite pools monitored over time. Cultivation on xylose generally resulted in gradual changes in metabolite pool size over time, whereas more dramatic fluctuations were observed with cultivation on glucose due to the diauxic growth pattern. The low G6P and F1,6P levels observed with cultivation on xylose resulted in the incomplete activation of the Crabtree effect, whereas the high PEP levels is indicative of carbon starvation. The high UDP-D-glucose levels with cultivation on xylose indicated that the carbon was channeled toward biomass production. The adenylate and guanylate energy charges were tightly regulated by the cultures, while the catabolic and anabolic reduction charges fluctuated between metabolic states. This study helped elucidate the metabolite distribution that takes place under Crabtree-positive and Crabtree-negative conditions when cultivating S. cerevisiae on glucose and xylose, respectively.

  10. Structure of a membrane-attack complex/perforin (MACPF) family protein from the human gut symbiont Bacteroides thetaiotaomicron

    International Nuclear Information System (INIS)

    Xu, Qingping; Abdubek, Polat; Astakhova, Tamara; Axelrod, Herbert L.; Bakolitsa, Constantina; Cai, Xiaohui; Carlton, Dennis; Chen, Connie; Chiu, Hsiu-Ju; Clayton, Thomas; Das, Debanu; Deller, Marc C.; Duan, Lian; Ellrott, Kyle; Farr, Carol L.; Feuerhelm, Julie; Grant, Joanna C.; Grzechnik, Anna; Han, Gye Won; Jaroszewski, Lukasz; Jin, Kevin K.; Klock, Heath E.; Knuth, Mark W.; Kozbial, Piotr; Krishna, S. Sri; Kumar, Abhinav; Lam, Winnie W.; Marciano, David; Miller, Mitchell D.; Morse, Andrew T.; Nigoghossian, Edward; Nopakun, Amanda; Okach, Linda; Puckett, Christina; Reyes, Ron; Tien, Henry J.; Trame, Christine B.; Bedem, Henry van den; Weekes, Dana; Wooten, Tiffany; Yeh, Andrew; Zhou, Jiadong; Hodgson, Keith O.; Wooley, John; Elsliger, Marc-André; Deacon, Ashley M.; Godzik, Adam; Lesley, Scott A.; Wilson, Ian A.

    2010-01-01

    The crystal structure of a novel MACPF protein, which may play a role in the adaptation of commensal bacteria to host environments in the human gut, was determined and analyzed. Membrane-attack complex/perforin (MACPF) proteins are transmembrane pore-forming proteins that are important in both human immunity and the virulence of pathogens. Bacterial MACPFs are found in diverse bacterial species, including most human gut-associated Bacteroides species. The crystal structure of a bacterial MACPF-domain-containing protein BT-3439 (Bth-MACPF) from B. thetaiotaomicron, a predominant member of the mammalian intestinal microbiota, has been determined. Bth-MACPF contains a membrane-attack complex/perforin (MACPF) domain and two novel C-terminal domains that resemble ribonuclease H and interleukin 8, respectively. The entire protein adopts a flat crescent shape, characteristic of other MACPF proteins, that may be important for oligomerization. This Bth-MACPF structure provides new features and insights not observed in two previous MACPF structures. Genomic context analysis infers that Bth-MACPF may be involved in a novel protein-transport or nutrient-uptake system, suggesting an important role for these MACPF proteins, which were likely to have been inherited from eukaryotes via horizontal gene transfer, in the adaptation of commensal bacteria to the host environment

  11. Analysis of the outer membrane proteome and secretome of Bacteroides fragilis reveals a multiplicity of secretion mechanisms.

    Directory of Open Access Journals (Sweden)

    Marlena M Wilson

    Full Text Available Bacteroides fragilis is a widely distributed member of the human gut microbiome and an opportunistic pathogen. Cell surface molecules produced by this organism likely play important roles in colonization, communication with other microbes, and pathogenicity, but the protein composition of the outer membrane (OM and the mechanisms used to transport polypeptides into the extracellular space are poorly characterized. Here we used LC-MS/MS to analyze the OM proteome and secretome of B. fragilis NCTC 9343 grown under laboratory conditions. Of the 229 OM proteins that we identified, 108 are predicted to be lipoproteins, and 61 are predicted to be TonB-dependent transporters. Based on their proximity to genes encoding TonB-dependent transporters, many of the lipoprotein genes likely encode proteins involved in nutrient or small molecule uptake. Interestingly, protease accessibility and biotinylation experiments indicated that an unusually large fraction of the lipoproteins are cell-surface exposed. We also identified three proteins that are members of a novel family of autotransporters, multiple potential type I protein secretion systems, and proteins that appear to be components of a type VI secretion apparatus. The secretome consisted of lipoproteins and other proteins that might be substrates of the putative type I or type VI secretion systems. Our proteomic studies show that B. fragilis differs considerably from well-studied Gram-negative bacteria such as Escherichia coli in both the spectrum of OM proteins that it produces and the range of secretion strategies that it utilizes.

  12. Structure of the GH76 α-mannanase homolog, BT2949, from the gut symbiont Bacteroides thetaiotaomicron

    International Nuclear Information System (INIS)

    Thompson, Andrew J.; Cuskin, Fiona; Spears, Richard J.; Dabin, Jerome; Turkenburg, Johan P.; Gilbert, Harry J.; Davies, Gideon J.

    2015-01-01

    A high-resolution structure of a noncanonical α-mannanase relevant to human health and nutrition has been solved via heavy-atom phasing of a selenomethionine derivative. The large bowel microbiota, a complex ecosystem resident within the gastrointestinal tract of all human beings and large mammals, functions as an essential, nonsomatic metabolic organ, hydrolysing complex dietary polysaccharides and modulating the host immune system to adequately tolerate ingested antigens. A significant member of this community, Bacteroides thetaiotaomicron, has evolved a complex system for sensing and processing a wide variety of natural glycoproducts in such a way as to provide maximum benefit to itself, the wider microbial community and the host. The immense ability of B. thetaiotaomicron as a ‘glycan specialist’ resides in its enormous array of carbohydrate-active enzymes, many of which are arranged into polysaccharide-utilization loci (PULs) that are able to degrade sugar polymers that are often inaccessible to other gut residents, notably α-mannan. The B. thetaiotaomicron genome encodes ten putative α-mannanases spread across various PULs; however, little is known about the activity of these enzymes or the wider implications of α-mannan metabolism for the health of both the microbiota and the host. In this study, SAD phasing of a selenomethionine derivative has been used to investigate the structure of one such B. thetaiotaomicron enzyme, BT2949, which belongs to the GH76 family of α-mannanases. BT2949 presents a classical (α/α) 6 -barrel structure comprising a large extended surface cleft common to other GH76 family members. Analysis of the structure in conjunction with sequence alignments reveals the likely location of the catalytic active site of this noncanonical GH76

  13. Biochemical and Structural Analyses of Two Cryptic Esterases in Bacteroides intestinalis and their Synergistic Activities with Cognate Xylanases.

    Science.gov (United States)

    Wefers, Daniel; Cavalcante, Janaina J V; Schendel, Rachel R; Deveryshetty, Jaigeeth; Wang, Kui; Wawrzak, Zdzislaw; Mackie, Roderick I; Koropatkin, Nicole M; Cann, Isaac

    2017-08-04

    Arabinoxylans are constituents of the human diet. Although not utilizable by the human host, they can be fermented by colonic bacteria. The arabinoxylan backbone is decorated with arabinose side chains that may be substituted with ferulic acid, thus limiting depolymerization to fermentable sugars. We investigated the polypeptides encoded by two genes upregulated during growth of the colonic bacterium Bacteroides intestinalis on wheat arabinoxylan. The recombinant proteins, designated BiFae1A and BiFae1B, were functionally assigned esterase activities. Both enzymes were active on acetylated substrates, although each showed a higher ferulic acid esterase activity on methyl-ferulate. BiFae1A showed a catalytic efficiency of 12mM s -1 on para-nitrophenyl-acetate, and on methyl-ferulate, the value was 27 times higher. BiFae1B showed low catalytic efficiencies for both substrates. Furthermore, the two enzymes released ferulic acid from various structural elements, and NMR spectroscopy indicated complete de-esterification of arabinoxylan oligosaccharides from wheat bran. BiFae1A is a tetramer based on the crystal structure, whereas BiFae1B is a dimer in solution based on size exclusion chromatography. The structure of BiFae1A was solved to 1.98Å resolution, and two tetramers were observed in the asymmetric unit. A flexible loop that may act as a hinge over the active site and likely coordinates critical interactions with the substrate was prominent in BiFae1A. Sequence alignments of the esterase domains in BiFae1B with the feruloyl esterase from Clostridium thermocellum suggest that both domains lack the flexible hinge in BiFae1A, an observation that may partly provide a molecular basis for the differences in activities in the two esterases. Copyright © 2017 Elsevier Ltd. All rights reserved.

  14. Structure of the GH76 α-mannanase homolog, BT2949, from the gut symbiont Bacteroides thetaiotaomicron

    Energy Technology Data Exchange (ETDEWEB)

    Thompson, Andrew J. [University of York, Heslington, York YO10 5DD (United Kingdom); Cuskin, Fiona [Newcastle University, Newcastle upon Tyne NE2 4HH (United Kingdom); Spears, Richard J.; Dabin, Jerome; Turkenburg, Johan P. [University of York, Heslington, York YO10 5DD (United Kingdom); Gilbert, Harry J., E-mail: harry.gilbert@newcastle.ac.uk [Newcastle University, Newcastle upon Tyne NE2 4HH (United Kingdom); Davies, Gideon J., E-mail: harry.gilbert@newcastle.ac.uk [University of York, Heslington, York YO10 5DD (United Kingdom)

    2015-02-01

    A high-resolution structure of a noncanonical α-mannanase relevant to human health and nutrition has been solved via heavy-atom phasing of a selenomethionine derivative. The large bowel microbiota, a complex ecosystem resident within the gastrointestinal tract of all human beings and large mammals, functions as an essential, nonsomatic metabolic organ, hydrolysing complex dietary polysaccharides and modulating the host immune system to adequately tolerate ingested antigens. A significant member of this community, Bacteroides thetaiotaomicron, has evolved a complex system for sensing and processing a wide variety of natural glycoproducts in such a way as to provide maximum benefit to itself, the wider microbial community and the host. The immense ability of B. thetaiotaomicron as a ‘glycan specialist’ resides in its enormous array of carbohydrate-active enzymes, many of which are arranged into polysaccharide-utilization loci (PULs) that are able to degrade sugar polymers that are often inaccessible to other gut residents, notably α-mannan. The B. thetaiotaomicron genome encodes ten putative α-mannanases spread across various PULs; however, little is known about the activity of these enzymes or the wider implications of α-mannan metabolism for the health of both the microbiota and the host. In this study, SAD phasing of a selenomethionine derivative has been used to investigate the structure of one such B. thetaiotaomicron enzyme, BT2949, which belongs to the GH76 family of α-mannanases. BT2949 presents a classical (α/α){sub 6}-barrel structure comprising a large extended surface cleft common to other GH76 family members. Analysis of the structure in conjunction with sequence alignments reveals the likely location of the catalytic active site of this noncanonical GH76.

  15. Degradation of fructans and production of propionic acid by Bacteroides thetaiotaomicron are enhanced by shortage of amino acids

    Directory of Open Access Journals (Sweden)

    Signe eAdamberg

    2014-12-01

    Full Text Available Bacteroides thetaiotaomicron is commonly found in the human colon and stabilizes its ecosystem by the catabolism of various polysaccharides. A model of cross-talk between the metabolism of amino acids and fructans in B. thetaiotaomicron was proposed. The growth of B. thetaiotaomicron DSM 2079 in two defined media containing mineral salts and vitamins, and supplemented with either 20 or 2 amino acids, was studied in an isothermal microcalorimeter. The polyfructans inulin (from chicory and levan (synthesized using levansucrase from Pseudomonas syringae, two fructooligosaccharide preparations with different composition, sucrose and fructose were tested as substrates. The calorimetric power-time curves were substrate specific and typically multiauxic. A surplus of amino acids reduced the consumption of longer oligosaccharides (DP > 3. Bacterial growth was not detected either in the carbohydrate free medium containing amino acids or in the medium with inulin as a sole carbohydrate. In amino acid-restricted medium, fermentation leading to acetic acid formation was dominant at the beginning of growth (up to 24 h, followed by increased lactic acid production, and mainly propionic and succinic acids were produced at the end of fermentation. In the medium supplemented with 20 amino acids, the highest production of D-lactate (82 ± 33 mmol/gDW occurred in parallel with extensive consumption (up to 17 mmol/gDW of amino acids, especially Ser, Thr and Asp. The production of Ala and Glu was observed at growth on all substrates, and the production was enhanced under amino acid deficiency. The study revealed the influence of amino acids on fructan metabolism in B. thetaiotaomicron and showed that defined growth media are invaluable in elucidating quantitative metabolic profiles of the bacteria. Levan was shown to act as an easily degradable substrate for B. thetaiotaomicron. The effect of levan on balancing or modifying colon microbiota will be studied in

  16. The colitis-associated transcriptional profile of commensal Bacteroides thetaiotaomicron enhances adaptive immune responses to a bacterial antigen.

    Directory of Open Access Journals (Sweden)

    Jonathan J Hansen

    Full Text Available Inflammatory bowel diseases (IBD may be caused in part by aberrant immune responses to commensal intestinal microbes including the well-characterized anaerobic gut commensal Bacteroides thetaiotaomicron (B. theta. Healthy, germ-free HLA-B27 transgenic (Tg rats develop chronic colitis when colonized with complex gut commensal bacteria whereas non-transgenic (nTg rats remain disease-free. However, the role of B. theta in causing disease in Tg rats is unknown nor is much known about how gut microbes respond to host inflammation.Tg and nTg rats were monoassociated with a human isolate of B. theta. Colonic inflammation was assessed by histologic scoring and tissue pro-inflammatory cytokine measurement. Whole genome transcriptional profiling of B. theta recovered from ceca was performed using custom GeneChips and data analyzed using dChip, Significance Analysis of Microarrays, and Gene Set Enrichment Analysis (GSEA software. Western Blots were used to determine adaptive immune responses to a differentially expressed B. theta gene.B. theta monoassociated Tg rats, but not nTg or germ-free controls, developed chronic colitis. Transcriptional profiles of cecal B. theta were significantly different in Tg vs. nTg rats. GSEA revealed that genes in KEGG canonical pathways involved in bacterial growth and metabolism were downregulated in B. theta from Tg rats with colitis though luminal bacterial concentrations were unaffected. Bacterial genes in the Gene Ontology molecular function "receptor activity", most of which encode nutrient binding proteins, were significantly upregulated in B. theta from Tg rats and include a SusC homolog that induces adaptive immune responses in Tg rats.B. theta induces colitis in HLA-B27 Tg rats, which is associated with regulation of bacterial genes in metabolic and nutrient binding pathways that may affect host immune responses. These studies of the host-microbial dialogue may lead to the identification of novel microbial targets

  17. Determination of thermodynamic parameters of benzylpenicillin hydrolysis by metallo-β-lactamase CcrA from Bacteroides fragilis

    Energy Technology Data Exchange (ETDEWEB)

    Zhai, Le; Zhou, Li-Sheng; Liu, Cheng-Cheng; Shi, Ying; Zhou, Ya-Jun [Key Laboratory of Synthetic and Natural Functional Molecule Chemistry of Ministry of Education, College of Chemistry and Materials Science, Northwest University, Xi’an 710069 (China); Yang, Ke-Wu, E-mail: kwyang@nwu.edu.cn [Key Laboratory of Synthetic and Natural Functional Molecule Chemistry of Ministry of Education, College of Chemistry and Materials Science, Northwest University, Xi’an 710069 (China)

    2013-03-20

    Highlights: ► First report the thermokinetic parameters of benzylpenicillin hydrolysis with CcrA. ► The hydrolysis is a spontaneous and exothermic reaction with order of 1.4. ► Summarized that CcrA prefer to hydrolyze penicillins among β-lactam antibiotics. - Abstract: One of the most common way that bacteria become resistant to antibiotics is by the production of metallo-β-lactamases (MβLs) to hydrolyze the β-lactam-containing antibiotics. In this paper, the thermodynamic parameters of benzylpenicillin hydrolysis with B1 subclasses MβL CcrA (carbapenem and cephamycin resistance) from Bacteroides fragilis were determined by microcalorimetry. The activation free energy ΔG{sub ≠}{sup θ} is 87.90 ± 0.03, 88.99 ± 0.01, 89.93 ± 0.04 and 90.93 ± 0.05 kJ mol{sup −1} at 293.15, 298.15, 303.15 and 308.15 K, activation enthalpy ΔH{sub ≠}{sup θ} is 29.21 ± 0.03 kJ mol{sup −1}, activation entropy ΔS{sub ≠}{sup θ} is −200.34 ± 0.08 J mol{sup −1} K{sup −1}, the reaction order is 1.4, and the apparent activation energy E is 31.71 kJ mol{sup −1}. The thermodynamic characterization indicated that CcrA prefer to hydrolyze penicillins among three kinds of β-lactam-containing antibiotics.

  18. Determination of thermodynamic parameters of benzylpenicillin hydrolysis by metallo-β-lactamase CcrA from Bacteroides fragilis

    International Nuclear Information System (INIS)

    Zhai, Le; Zhou, Li-Sheng; Liu, Cheng-Cheng; Shi, Ying; Zhou, Ya-Jun; Yang, Ke-Wu

    2013-01-01

    Highlights: ► First report the thermokinetic parameters of benzylpenicillin hydrolysis with CcrA. ► The hydrolysis is a spontaneous and exothermic reaction with order of 1.4. ► Summarized that CcrA prefer to hydrolyze penicillins among β-lactam antibiotics. - Abstract: One of the most common way that bacteria become resistant to antibiotics is by the production of metallo-β-lactamases (MβLs) to hydrolyze the β-lactam-containing antibiotics. In this paper, the thermodynamic parameters of benzylpenicillin hydrolysis with B1 subclasses MβL CcrA (carbapenem and cephamycin resistance) from Bacteroides fragilis were determined by microcalorimetry. The activation free energy ΔG ≠ θ is 87.90 ± 0.03, 88.99 ± 0.01, 89.93 ± 0.04 and 90.93 ± 0.05 kJ mol −1 at 293.15, 298.15, 303.15 and 308.15 K, activation enthalpy ΔH ≠ θ is 29.21 ± 0.03 kJ mol −1 , activation entropy ΔS ≠ θ is −200.34 ± 0.08 J mol −1 K −1 , the reaction order is 1.4, and the apparent activation energy E is 31.71 kJ mol −1 . The thermodynamic characterization indicated that CcrA prefer to hydrolyze penicillins among three kinds of β-lactam-containing antibiotics

  19. Detection of Increased Plasma Interleukin-6 Levels and Prevalence of Prevotella copri and Bacteroides vulgatus in the Feces of Type 2 Diabetes Patients

    Science.gov (United States)

    Leite, Aline Zazeri; Rodrigues, Nathália de Campos; Gonzaga, Marina Ignácio; Paiolo, João Carlos Cicogna; de Souza, Carolina Arantes; Stefanutto, Nadine Aparecida Vicentini; Omori, Wellington Pine; Pinheiro, Daniel Guariz; Brisotti, João Luiz; Matheucci Junior, Euclides; Mariano, Vânia Sammartino; de Oliveira, Gislane Lelis Vilela

    2017-01-01

    Intestinal dysbiosis and metabolic endotoxemia have been associated with metabolic disorders, such as obesity, insulin resistance, and type 2 diabetes (T2D). The main goal of the present study was to evaluate the intestinal dysbiosis in Brazilian T2D patients and correlate these data with inflammatory cytokines and lipopolysaccharides (LPS) plasma concentrations. This study was approved by the Ethics Committees from Barretos Cancer Hospital and all individuals signed the informed consent form. Stool samples were required for DNA extraction, and the V3/V4 regions of bacterial 16S were sequenced using an Illumina platform. Peripheral blood was used to quantify inflammatory cytokines and plasma LPS concentrations, by CBA flex and ELISA, respectively. Statistical analyses were performed using Mann–Whitney and Spearman’s tests. Analysis of variance, diversity indexes, and analysis of alpha- and beta-diversity were conducted using an annotated Operational Taxonomic Unit table. This study included 20 patients and 22 controls. We observed significant differences (P Prevotella copri, Bacteroides vulgatus, Bacteroides rodentium, and Bacteroides xylanisolvens. The proinflammatory interleukin-6 (IL-6) was significantly increased (P Prevotella species, and a positive correlation between the LPS levels and P. copri reads. The P. copri and B. vulgatus species were associated with insulin resistance in previous studies. In this study, we suggested that the prevalence of Gram-negative species in the gut and the increased plasma IL-6 in patients could be linked to low-grade inflammation and insulin resistance. In conclusion, the P. copri and B. vulgatus species could represent an intestinal microbiota signature, associated with T2D development. Furthermore, the identification of these Gram-negative bacteria, and the detection of inflammatory markers, such as increased IL-6, could be used as diabetes predictive markers in overweight, obese and in genetically predisposed

  20. Detection of Increased Plasma Interleukin-6 Levels and Prevalence ofPrevotella copriandBacteroides vulgatusin the Feces of Type 2 Diabetes Patients.

    Science.gov (United States)

    Leite, Aline Zazeri; Rodrigues, Nathália de Campos; Gonzaga, Marina Ignácio; Paiolo, João Carlos Cicogna; de Souza, Carolina Arantes; Stefanutto, Nadine Aparecida Vicentini; Omori, Wellington Pine; Pinheiro, Daniel Guariz; Brisotti, João Luiz; Matheucci Junior, Euclides; Mariano, Vânia Sammartino; de Oliveira, Gislane Lelis Vilela

    2017-01-01

    Intestinal dysbiosis and metabolic endotoxemia have been associated with metabolic disorders, such as obesity, insulin resistance, and type 2 diabetes (T2D). The main goal of the present study was to evaluate the intestinal dysbiosis in Brazilian T2D patients and correlate these data with inflammatory cytokines and lipopolysaccharides (LPS) plasma concentrations. This study was approved by the Ethics Committees from Barretos Cancer Hospital and all individuals signed the informed consent form. Stool samples were required for DNA extraction, and the V3/V4 regions of bacterial 16S were sequenced using an Illumina platform. Peripheral blood was used to quantify inflammatory cytokines and plasma LPS concentrations, by CBA flex and ELISA, respectively. Statistical analyses were performed using Mann-Whitney and Spearman's tests. Analysis of variance, diversity indexes, and analysis of alpha- and beta-diversity were conducted using an annotated Operational Taxonomic Unit table. This study included 20 patients and 22 controls. We observed significant differences ( P  Prevotella copri, Bacteroides vulgatus, Bacteroides rodentium , and Bacteroides xylanisolvens . The proinflammatory interleukin-6 (IL-6) was significantly increased ( P  Prevotella species, and a positive correlation between the LPS levels and P. copri reads. The P. copri and B. vulgatus species were associated with insulin resistance in previous studies. In this study, we suggested that the prevalence of Gram-negative species in the gut and the increased plasma IL-6 in patients could be linked to low-grade inflammation and insulin resistance. In conclusion, the P. copri and B. vulgatus species could represent an intestinal microbiota signature, associated with T2D development. Furthermore, the identification of these Gram-negative bacteria, and the detection of inflammatory markers, such as increased IL-6, could be used as diabetes predictive markers in overweight, obese and in genetically predisposed

  1. Monocolonization with Bacteroides ovatus protects immunodeficient SCID mice from mortality in chronic intestinal inflammation caused by long-lasting dextran sodium sulfate treatment

    Czech Academy of Sciences Publication Activity Database

    Hudcovic, Tomáš; Kozáková, Hana; Kolínská, Jiřina; Štěpánková, Renata; Hrnčíř, Tomáš; Tlaskalová, Helena

    2009-01-01

    Roč. 58, č. 1 (2009), s. 101-110 ISSN 0862-8408 R&D Projects: GA ČR GA303/04/0849; GA ČR GA303/08/0367; GA ČR(CZ) GA303/05/2249; GA ČR GA303/06/0974; GA MŠk 2B06053; GA MŠk 2B06155; GA AV ČR 1QS500200572 Institutional research plan: CEZ:AV0Z50200510; CEZ:AV0Z50110509 Keywords : bacteroides ovatus * ulcerative colitis * dextran sulfate sodium colitis Subject RIV: EC - Immunology Impact factor: 1.430, year: 2009

  2. Detection of Increased Plasma Interleukin-6 Levels and Prevalence of Prevotella copri and Bacteroides vulgatus in the Feces of Type 2 Diabetes Patients

    Directory of Open Access Journals (Sweden)

    Aline Zazeri Leite

    2017-09-01

    Full Text Available Intestinal dysbiosis and metabolic endotoxemia have been associated with metabolic disorders, such as obesity, insulin resistance, and type 2 diabetes (T2D. The main goal of the present study was to evaluate the intestinal dysbiosis in Brazilian T2D patients and correlate these data with inflammatory cytokines and lipopolysaccharides (LPS plasma concentrations. This study was approved by the Ethics Committees from Barretos Cancer Hospital and all individuals signed the informed consent form. Stool samples were required for DNA extraction, and the V3/V4 regions of bacterial 16S were sequenced using an Illumina platform. Peripheral blood was used to quantify inflammatory cytokines and plasma LPS concentrations, by CBA flex and ELISA, respectively. Statistical analyses were performed using Mann–Whitney and Spearman’s tests. Analysis of variance, diversity indexes, and analysis of alpha- and beta-diversity were conducted using an annotated Operational Taxonomic Unit table. This study included 20 patients and 22 controls. We observed significant differences (P < 0.01 in the microbiota composition (beta-diversity between patients and controls, suggesting intestinal dysbiosis in Brazilian T2D patients. The prevalent species found in patients’ feces were the Gram-negatives Prevotella copri, Bacteroides vulgatus, Bacteroides rodentium, and Bacteroides xylanisolvens. The proinflammatory interleukin-6 (IL-6 was significantly increased (P < 0.05 in patients’ plasma and LPS levels were decreased. We find correlations between the proinflammatory interferon-gamma with Gram-negatives Bacteroides and Prevotella species, and a positive correlation between the LPS levels and P. copri reads. The P. copri and B. vulgatus species were associated with insulin resistance in previous studies. In this study, we suggested that the prevalence of Gram-negative species in the gut and the increased plasma IL-6 in patients could be linked to low

  3. In Vitro Anaerobic Pharmacokinetic/Pharmacodynamic Model to Simulate the Bactericidal Activity of Levornidazole Against Bacteroides fragilis.

    Science.gov (United States)

    Hu, Jiali; Zhang, Jing; Chen, Yuancheng; Liang, Wang; Wu, Shi

    2017-04-01

    This study was designed to correlate the pharmacokinetic/pharmacodynamic (PK/PD) parameters with PD indices of levornidazole against Bacteroides fragilis and to calculate the PK/PD target value for levornidazole to attain its expected maximal bactericidal effect using an in vitro anaerobic dynamic PK/PD model. An anaerobic dynamic PK/PD model was developed in vitro. The scheme for PK modeling was designed according to the PK parameters of levornidazole in the human body. The device of 2-compartment PK/PD model was constructed by using digital control of flow rate to simulate 4 regimens of single-dose intravenous infusion of levornidazole to determine the bactericidal activity of levornidazole against the 3 strains of B fragilis within 72 hours. PD parameters such as reduction of colony count within 24 hours (∆Log 24h ), area under bactericidal curve (AUBC), and 2-hour initial killing rate (IKR) were calculated and correlated with PK/PD parameters. Sigmoid E max model of levornidazole was established to calculate PK/PD target values to attain corresponding PD effect. PK and PD validation proved the stability of the model in simulating levornidazole against B fragilis and the precision and accuracy in the results of PK modeling. C max and AUC 0-24h found only -1.46% and -6.72% differences from the values in vivo. Our study found that ∆Log 24h , AUBC, and IKR were more correlated with AUC 0-24h /MIC and C max /MIC than with %T>MIC. According to ∆Log 24h , the PK/PD target values of AUC 0-24h /MIC, C max /MIC, and %T>MIC of levornidazole against B fragilis were 157.6%, 14.1%, and 56.4%, respectively. Our findings are useful for optimizing the clinical dosing regimen of levornidazole sodium chloride injection to attain maximal bactericidal effect. Copyright © 2017 Elsevier HS Journals, Inc. All rights reserved.

  4. Consistency in the host specificity and host sensitivity of the Bacteroides HF183 marker for sewage pollution tracking.

    Science.gov (United States)

    Ahmed, W; Masters, N; Toze, S

    2012-10-01

    The host specificity (H-SPF) and host sensitivity (H-SNV) values of the sewage-associated HF183 Bacteroides marker in the current study were compared with the previously published studies in South East Queensland (SEQ), Australia, by testing a large number of wastewater and faecal DNA samples (n=293) from 11 target and nontarget host groups. This was carried out to obtain information on the consistency in the H-SPF and H-SNV values of the HF183 marker for sewage pollution tracking in SEQ. Polymerase chain reaction (PCR) analysis was used to determine the presence/absence of the HF183 marker in wastewater and faecal DNA samples. Among the human composite wastewater (n=59) from sewage treatment plants and individual human (n=20) faecal DNA samples tested, 75 (95%) were PCR positive for the HF183 marker. The overall H-SNV of this marker in target host group was 0·95 (maximum of 1·00). Among the 214 nontarget animal faecal DNA samples tested, 201 (94%) samples were negative for the HF183 marker. Six chicken, five dog and two bird faecal DNA samples, however, were positive for the marker. The overall H-SPF of the HF183 marker to differentiate between target and nontarget faecal DNA samples was 0·94 (maximum of 1·00). The H-SNV (0·95) and H-SPF (0·94) values obtained in this study was slightly lower than previous studies (H-SNV value of 1·00 in 2007 and 1·00 in 2009; H-SPF value of 1·00 in 2007 and 0·99 in 2009). Nonetheless, the overall high H-SNV (0·98) and H-SPF (0·97) values of the HF183 marker over the past 4 years (i.e. 2007-2011) suggest that the HF183 marker can be reliably used for the detection of sewage pollution in environmental waters in SEQ. In the current study, the HF183 marker was detected in small number nontarget animal faecal samples. Care should be taken to interpret results obtained from catchments or waterways that might be potentially contaminated with dog faecal matter or poultry litter. © 2012 The Authors. Letters in Applied

  5. Salmonella-induced changes in the gut microbiota and immune response genes transcriptome during administration of vancomycin and Bacteroides fragilis

    Directory of Open Access Journals (Sweden)

    Yu. V. Bukina

    2017-04-01

    Full Text Available The aim. To study Salmonella-induced changes in the intestinal wall microbiota, the expression of Salmonella effector proteins SipA, SopB, SopE2 and transcriptional activity of genes FFAR2, Foxp3, RORγt in rat GALT during administration of vancomycin and B.fragilis. Methods. Investigations of qualitative and quantitative composition of the microbiota of the wall of the small intestine were carried out, and the expression level of rat genes Foxp3, Rorc (Royt, FFAR2 and Salmonella effector proteins SipA, SopB and SopE2 were determined by RT-PCR, the relationship between groups of microorganisms was established. Results. Administration of B.fragilis against the background pre-treatment with vancomycin and Salmonella infection alters the quantitative composition of the microbiota in the wall of the small intestine contents: a decrease in Salmonella spp., E.coli, P.aeruginosa, Proteus spp., Enterobacter spp., Klebsiella spp. and Shigella spp., as well as increasing Bacteroides spp., E.faecalis, E.faecium and Peptostreptococcus anaerobius. The level of expression of Salmonella effector proteins in animals with the combined administration of vancomycin and S.enteritidis (I group, S.typhimurium (II group increased: SopB – 101 and 20 times; SopE2 - 80 and 2 times; SipA - 613 times (II group, and also 5-fold decrease was noted in the I group. Relative normalized number of mRNA of genes FFAR2, Foxp3, RORγt in GALT of rats in groups III and IV increased: FFAR2 - 2.7 and 5.4 times; Foxp3 - 2.5 and 85 times, RORγt level decreased by 70% and only in IV group. Conclusions. Using B.fragilis creates conditions for the correction of Salmonella-induced changes of the intestinal microbiome. Pretreatment of animals with vancomycin causes increased transcriptional activity of genes SipA, SopB and SopE2, except SipA after administration of S.enteritidis. Administration of B.fragilis increases the level of mRNA of genes FFAR2 and Foxp3 in GALT and reduces ROR

  6. Scientific Opinion on the safety of ‘heat-treated milk products fermented with Bacteroides xylanisolvens DSM 23964’ as a novel food

    DEFF Research Database (Denmark)

    Tetens, Inge; Poulsen, Morten

    2015-01-01

    Following a request from the European Commission, the EFSA NDA Panel was asked to carry out the additional assessment for ‘pasteurised milk products fermented with Bacteroides xylanisolvens DSM 23964’ as a novel food (NF) in the context of Regulation (EC) No 258/97. Pasteurised or ultra-high-temp......Following a request from the European Commission, the EFSA NDA Panel was asked to carry out the additional assessment for ‘pasteurised milk products fermented with Bacteroides xylanisolvens DSM 23964’ as a novel food (NF) in the context of Regulation (EC) No 258/97. Pasteurised or ultra......-high-temperature-treated milk is used for the fermentation process with B. xylanisolvens DSM 23964. After fermentation the product is heat treated for one hour at 75 °C to ensure the absence of viable B. xylanisolvens DSM 23964. The Panel considers the information provided on the identity and characterisation of B....... xylanisolvens DSM 23964 to be sufficient. The production process encompasses standard techniques used by the dairy industry, is sufficiently described by the applicant and does not give rise to safety concerns. The Panel considers that the information provided on the production process and on the content...

  7. In vitro activity of trovafloxacin against Bacteroides fragilis in mixed culture with either Escherichia coli or a vancomycin- resistant strain of Enterococcus faecium determined by an anaerobic time-kill technique.

    NARCIS (Netherlands)

    L.E.T. Stearne (Lorna); C. Kooi; W.H.F. Goessens (Wil); I.A.J.M. Bakker-Woudenberg (Irma); I.C. Gyssens (Inge)

    2001-01-01

    textabstractTo determine the efficacy of trovafloxacin as a possible treatment for intra-abdominal abscesses, we have developed an anaerobic time-kill technique using different inocula to study the in vitro killing of Bacteroides fragilis in pure culture or in mixed

  8. Microbial enterotypes, inferred by the prevotella-to-bacteroides ratio, remained stable during a 6-month randomized controlled diet intervention with the new nordic diet

    DEFF Research Database (Denmark)

    Roager, Henrik Munch; Licht, Tine Rask; Poulsen, Sanne

    2014-01-01

    It has been suggested that the human gut microbiota can be divided into enterotypes based on the abundance of specific bacterial groups; however, the biological significance and stability of these enterotypes remain unresolved. Here, we demonstrated that subjects (n = 62) 18 to 65 years old...... with central obesity and components of metabolic syndrome could be grouped into two discrete groups simply by their relative abundance of Prevotella spp. divided by Bacteroides spp. (P/B ratio) obtained by quantitative PCR analysis. Furthermore, we showed that these groups remained stable during a 6-month......, controlled dietary intervention, where the effect of consuming a diet in accord with the new Nordic diet (NND) recommendations as opposed to consuming the average Danish diet (ADD) on the gut microbiota was investigated. In this study, subjects (with and without stratification according to P/B ratio) did...

  9. Pre-treatment microbial Prevotella-to-Bacteroides ratio, determines body fat loss success during a 6-month randomized controlled diet intervention

    DEFF Research Database (Denmark)

    Hjorth, M F; Roager, Henrik Munch; Larsen, T. M.

    2017-01-01

    Based on the abundance of specific bacterial genera, the human gut microbiota can be divided into two relatively stable groups that might play a role in personalized nutrition. We studied these simplified enterotypes as prognostic markers for successful body fat loss on two different diets. A total....... divided by Bacteroides spp. (P/B ratio) obtained by quantitative PCR analysis. Modifications of dietary effects of pre-treatment P/B group were examined by linear mixed models. Among individuals with high P/B the NND resulted in a 3.15 kg (95%CI 1.55;4.76, Pfat loss compared to ADD...... to lose body fat on diets high in fiber and wholegrain than subjects with a low P/B-ratio....

  10. Pre-treatment microbial Prevotella-to-Bacteroides ratio, determines body fat loss success during a 6-month randomized controlled diet intervention

    DEFF Research Database (Denmark)

    Hjorth, M F; Roager, Henrik Munch; Larsen, T. M.

    2017-01-01

    Based on the abundance of specific bacterial genera, the human gut microbiota can be divided into two relatively stable groups that might play a role in personalized nutrition. We studied these simplified enterotypes as prognostic markers for successful body fat loss on two different diets. A total...... of 62 participants with increased waist circumference were randomly assigned to receive an ad libitum New Nordic Diet (NND) high in fiber/wholegrain or an Average Danish Diet (ADD) for 26 weeks. Participants were grouped into two discrete enterotypes by their relative abundance of Prevotella spp....... divided by Bacteroides spp. (P/B ratio) obtained by quantitative PCR analysis. Modifications of dietary effects of pre-treatment P/B group were examined by linear mixed models. Among individuals with high P/B the NND resulted in a 3.15 kg (95%CI 1.55;4.76, Ploss compared to ADD...

  11. Prebiotic effects of wheat arabinoxylan related to the increase in bifidobacteria, Roseburia and Bacteroides/Prevotella in diet-induced obese mice.

    Science.gov (United States)

    Neyrinck, Audrey M; Possemiers, Sam; Druart, Céline; Van de Wiele, Tom; De Backer, Fabienne; Cani, Patrice D; Larondelle, Yvan; Delzenne, Nathalie M

    2011-01-01

    Alterations in the composition of gut microbiota--known as dysbiosis--has been proposed to contribute to the development of obesity, thereby supporting the potential interest of nutrients targeting the gut with beneficial effect for host adiposity. We test the ability of a specific concentrate of water-extractable high molecular weight arabinoxylans (AX) from wheat to modulate both the gut microbiota and lipid metabolism in high-fat (HF) diet-induced obese mice. Mice were fed either a control diet (CT) or a HF diet, or a HF diet supplemented with AX (10% w/w) during 4 weeks. AX supplementation restored the number of bacteria that were decreased upon HF feeding, i.e. Bacteroides-Prevotella spp. and Roseburia spp. Importantly, AX treatment markedly increased caecal bifidobacteria content, in particular Bifidobacterium animalis lactis. This effect was accompanied by improvement of gut barrier function and by a lower circulating inflammatory marker. Interestingly, rumenic acid (C18:2 c9,t11) was increased in white adipose tissue due to AX treatment, suggesting the influence of gut bacterial metabolism on host tissue. In parallel, AX treatment decreased adipocyte size and HF diet-induced expression of genes mediating differentiation, fatty acid uptake, fatty acid oxidation and inflammation, and decreased a key lipogenic enzyme activity in the subcutaneous adipose tissue. Furthermore, AX treatment significantly decreased HF-induced adiposity, body weight gain, serum and hepatic cholesterol accumulation and insulin resistance. Correlation analysis reveals that Roseburia spp. and Bacteroides/Prevotella levels inversely correlate with these host metabolic parameters. Supplementation of a concentrate of water-extractable high molecular weight AX in the diet counteracted HF-induced gut dysbiosis together with an improvement of obesity and lipid-lowering effects. We postulate that hypocholesterolemic, anti-inflammatory and anti-obesity effects are related to changes in gut

  12. Monitoring Bacteroides spp. markers, nutrients, metals and Escherichia coli in soil and leachate after land application of three types of municipal biosolids.

    Science.gov (United States)

    McCall, Crystal A; Jordan, Katerina S; Habash, Marc B; Dunfield, Kari E

    2015-03-01

    A lysimeter-based field study was done to monitor the transfer of culturable Escherichia coli, general (ALLBAC), human (Hf183) and swine (PIG-BAC-1) specific 16S rRNA Bacteroides spp. markers, nutrients and metals through soils and leachate over time following land application of a CP1/Class A as well as two CP2/Class B municipal biosolids (MBs). Hf183 markers were detected up to six days following application in soils receiving dewatered and liquid MBs, but not in leachate, suggesting their use in source tracking is better suited for recent pollution events. The CP2/Class B biosolids and swine manure contributed the highest microbial load with E. coli loads (between 2.5 and 3.7 log CFU (100 mL)(-1)) being greater than North American concentration recommendations for safe recreational water. ALLBAC persisted in soils and leachate receiving all treatments and was detected prior to amendment application demonstrating its unsuitability for identifying the presence of fecal pollution. A significant increase in NO₃-N (for Lystek and dewatered MBs) and total-P (for dewatered and liquid MBs) in leachate was observed in plots receiving the CP1/Class A and CP2/Class B type MBs which exceeded North American guidelines, suggesting impact to surface water. Metal (As, Cd, Cr, Co, Cu, Pb, Mo, Ni, Se, Zn and Hg) transfer was negligible in soil and leachate samples receiving all treatments. This study is one of the first to examine the fate of E. coli and Bacteroides spp. markers in situ following the land application of MBs where surface runoff does not apply. Copyright © 2014 Elsevier Ltd. All rights reserved.

  13. In Silico Analysis of the Small Molecule Content of Outer Membrane Vesicles Produced by Bacteroides thetaiotaomicron Indicates an Extensive Metabolic Link between Microbe and Host

    Directory of Open Access Journals (Sweden)

    William A. Bryant

    2017-12-01

    Full Text Available The interactions between the gut microbiota and its host are of central importance to the health of the host. Outer membrane vesicles (OMVs are produced ubiquitously by Gram-negative bacteria including the gut commensal Bacteroides thetaiotaomicron. These vesicles can interact with the host in various ways but until now their complement of small molecules has not been investigated in this context. Using an untargeted high-coverage metabolomic approach we have measured the small molecule content of these vesicles in contrasting in vitro conditions to establish what role these metabolites could perform when packed into these vesicles. B. thetaiotaomicron packs OMVs with a highly conserved core set of small molecules which are strikingly enriched with mouse-digestible metabolites and with metabolites previously shown to be associated with colonization of the murine GIT. By use of an expanded genome-scale metabolic model of B. thetaiotaomicron and a potential host (the mouse we have established many possible metabolic pathways between the two organisms that were previously unknown, and have found several putative novel metabolic functions for mouse that are supported by gene annotations, but that do not currently appear in existing mouse metabolic networks. The lipidome of these OMVs bears no relation to the mouse lipidome, so the purpose of this particular composition of lipids remains unclear. We conclude from this analysis that through intimate symbiotic evolution OMVs produced by B. thetaiotaomicron are likely to have been adopted as a conduit for small molecules bound for the mammalian host in vivo.

  14. The Dysregulation of Polyamine Metabolism in Colorectal Cancer Is Associated with Overexpression of c-Myc and C/EBPβ rather than Enterotoxigenic Bacteroides fragilis Infection

    Directory of Open Access Journals (Sweden)

    Anastasiya V. Snezhkina

    2016-01-01

    Full Text Available Colorectal cancer is one of the most common cancers in the world. It is well known that the chronic inflammation can promote the progression of colorectal cancer (CRC. Recently, a number of studies revealed a potential association between colorectal inflammation, cancer progression, and infection caused by enterotoxigenic Bacteroides fragilis (ETBF. Bacterial enterotoxin activates spermine oxidase (SMO, which produces spermidine and H2O2 as byproducts of polyamine catabolism, which, in turn, enhances inflammation and tissue injury. Using qPCR analysis, we estimated the expression of SMOX gene and ETBF colonization in CRC patients. We found no statistically significant associations between them. Then we selected genes involved in polyamine metabolism, metabolic reprogramming, and inflammation regulation and estimated their expression in CRC. We observed overexpression of SMOX, ODC1, SRM, SMS, MTAP, c-Myc, C/EBPβ (CREBP, and other genes. We found that two mediators of metabolic reprogramming, inflammation, and cell proliferation c-Myc and C/EBPβ may serve as regulators of polyamine metabolism genes (SMOX, AZIN1, MTAP, SRM, ODC1, AMD1, and AGMAT as they are overexpressed in tumors, have binding site according to ENCODE ChIP-Seq data, and demonstrate strong coexpression with their targets. Thus, increased polyamine metabolism in CRC could be driven by c-Myc and C/EBPβ rather than ETBF infection.

  15. RbohB, a Phaseolus vulgaris NADPH oxidase gene, enhances symbiosome number, bacteroid size, and nitrogen fixation in nodules and impairs mycorrhizal colonization.

    Science.gov (United States)

    Arthikala, Manoj-Kumar; Sánchez-López, Rosana; Nava, Noreide; Santana, Olivia; Cárdenas, Luis; Quinto, Carmen

    2014-05-01

    The reactive oxygen species (ROS) generated by respiratory burst oxidative homologs (Rbohs) are involved in numerous plant cell signaling processes, and have critical roles in the symbiosis between legumes and nitrogen-fixing bacteria. Previously, down-regulation of RbohB in Phaseolus vulgaris was shown to suppress ROS production and abolish Rhizobium infection thread (IT) progression, but also to enhance arbuscular mycorrhizal fungal (AMF) colonization. Thus, Rbohs function both as positive and negative regulators. Here, we assessed the effect of enhancing ROS concentrations, by overexpressing PvRbohB, on the P. vulgaris--rhizobia and P. vulgaris--AMF symbioses. We estimated superoxide concentrations in hairy roots overexpressing PvRbohB, determined the status of early and late events of both Rhizobium and AMF interactions in symbiont-inoculated roots, and analyzed the nodule ultrastructure of transgenic plants overexpressing PvRbohB. Overexpression of PvRbohB significantly enhanced ROS production, the formation of ITs, nodule biomass, and nitrogen-fixing activity, and increased the density of symbiosomes in nodules, and the density and size of bacteroides in symbiosomes. Furthermore, PvCAT, early nodulin, PvSS1, and PvGOGAT transcript abundances were elevated in these nodules. By contrast, mycorrhizal colonization was reduced in roots that overexpressed RbohB. Overexpression of PvRbohB augmented nodule efficiency by enhancing nitrogen fixation and delaying nodule senescence, but impaired AMF colonization. © 2014 The Authors. New Phytologist © 2014 New Phytologist Trust.

  16. Vitamin B12 Uptake by the Gut Commensal Bacteria Bacteroides thetaiotaomicron Limits the Production of Shiga Toxin by Enterohemorrhagic Escherichia coli

    Directory of Open Access Journals (Sweden)

    Charlotte Cordonnier

    2016-01-01

    Full Text Available Enterohemorrhagic Escherichia coli (EHEC are foodborne pathogens responsible for the development of bloody diarrhea and renal failure in humans. Many environmental factors have been shown to regulate the production of Shiga toxin 2 (Stx2, the main virulence factor of EHEC. Among them, soluble factors produced by human gut microbiota and in particular, by the predominant species Bacteroides thetaiotaomicron (B. thetaiotaomicron, inhibit Stx2 gene expression. In this study, we investigated the molecular mechanisms underlying the B. thetaiotaomicron-dependent inhibition of Stx2 production by EHEC. We determined that Stx2-regulating molecules are resistant to heat treatment but do not correspond to propionate and acetate, two short-chain fatty acids produced by B. thetaiotaomicron. Moreover, screening of a B. thetaiotaomicron mutant library identified seven mutants that do not inhibit Stx2 synthesis by EHEC. One mutant has impaired production of BtuB, an outer membrane receptor for vitamin B12. Together with restoration of Stx2 level after vitamin B12 supplementation, these data highlight vitamin B12 as a molecule produced by gut microbiota that modulates production of a key virulence factor of EHEC and consequently may affect the outcome of an infection.

  17. Vitamin B12 Uptake by the Gut Commensal Bacteria Bacteroides thetaiotaomicron Limits the Production of Shiga Toxin by Enterohemorrhagic Escherichia coli.

    Science.gov (United States)

    Cordonnier, Charlotte; Le Bihan, Guillaume; Emond-Rheault, Jean-Guillaume; Garrivier, Annie; Harel, Josée; Jubelin, Grégory

    2016-01-05

    Enterohemorrhagic Escherichia coli (EHEC) are foodborne pathogens responsible for the development of bloody diarrhea and renal failure in humans. Many environmental factors have been shown to regulate the production of Shiga toxin 2 (Stx2), the main virulence factor of EHEC. Among them, soluble factors produced by human gut microbiota and in particular, by the predominant species Bacteroides thetaiotaomicron (B. thetaiotaomicron), inhibit Stx2 gene expression. In this study, we investigated the molecular mechanisms underlying the B. thetaiotaomicron-dependent inhibition of Stx2 production by EHEC. We determined that Stx2-regulating molecules are resistant to heat treatment but do not correspond to propionate and acetate, two short-chain fatty acids produced by B. thetaiotaomicron. Moreover, screening of a B. thetaiotaomicron mutant library identified seven mutants that do not inhibit Stx2 synthesis by EHEC. One mutant has impaired production of BtuB, an outer membrane receptor for vitamin B12. Together with restoration of Stx2 level after vitamin B12 supplementation, these data highlight vitamin B12 as a molecule produced by gut microbiota that modulates production of a key virulence factor of EHEC and consequently may affect the outcome of an infection.

  18. Distribution, detection of enterotoxigenic strains and antimicrobial drug susceptibility patterns of Bacteroides fragilis group in diarrheic and non-diarrheic feces from Brazilian infants

    Directory of Open Access Journals (Sweden)

    Débora Paula Ferreira

    2010-10-01

    Full Text Available Despite the importance of gastrointestinal diseases and their global distribution, affecting millions of individuals around the world, the role and antimicrobial susceptibility patterns of anaerobic bacteria such as those in the Bacteroides fragilis group (BFG are still unclear in young children. This study investigated the occurrence and distribution of species in the BFG and enterotoxigenic strains in the fecal microbiota of children and their antimicrobial susceptibility patterns. Diarrheic (n=110 and non-diarrheic (n=65 fecal samples from children aged 0-5 years old were evaluated. BFG strains were isolated and identified by conventional biochemical, physiological and molecular approaches. Alternatively, bacteria and enterotoxigenic strains were detected directly from feces by molecular biology. Antimicrobial drug susceptibility patterns were determined by the agar dilution method according to the guidelines for isolated bacteria. BFG was detected in 64.3% of the fecal samples (55% diarrheic and 80.4% non-diarrheic, and 4.6% were enterotoxigenic. Antimicrobial resistance was observed against ampicillin, ampicillin/sulbactam, piperacillin/tazobactam, meropenem, ceftriaxone, clindamycin and chloramphenicol. The data show that these bacteria are prevalent in fecal microbiota at higher levels in healthy children. The molecular methodology was more effective in identifying the B. fragilis group when compared to the biochemical and physiological techniques. The observation of high resistance levels stimulates thoughts about the indiscriminate use of antimicrobial drugs in early infancy. Further quantitative studies are needed to gain a better understanding of the role of these bacteria in acute diarrhea in children.

  19. Vitamin B12 Uptake by the Gut Commensal Bacteria Bacteroides thetaiotaomicron Limits the Production of Shiga Toxin by Enterohemorrhagic Escherichia coli

    Science.gov (United States)

    Cordonnier, Charlotte; Le Bihan, Guillaume; Emond-Rheault, Jean-Guillaume; Garrivier, Annie; Harel, Josée; Jubelin, Grégory

    2016-01-01

    Enterohemorrhagic Escherichia coli (EHEC) are foodborne pathogens responsible for the development of bloody diarrhea and renal failure in humans. Many environmental factors have been shown to regulate the production of Shiga toxin 2 (Stx2), the main virulence factor of EHEC. Among them, soluble factors produced by human gut microbiota and in particular, by the predominant species Bacteroides thetaiotaomicron (B. thetaiotaomicron), inhibit Stx2 gene expression. In this study, we investigated the molecular mechanisms underlying the B. thetaiotaomicron-dependent inhibition of Stx2 production by EHEC. We determined that Stx2-regulating molecules are resistant to heat treatment but do not correspond to propionate and acetate, two short-chain fatty acids produced by B. thetaiotaomicron. Moreover, screening of a B. thetaiotaomicron mutant library identified seven mutants that do not inhibit Stx2 synthesis by EHEC. One mutant has impaired production of BtuB, an outer membrane receptor for vitamin B12. Together with restoration of Stx2 level after vitamin B12 supplementation, these data highlight vitamin B12 as a molecule produced by gut microbiota that modulates production of a key virulence factor of EHEC and consequently may affect the outcome of an infection. PMID:26742075

  20. Structures of complexes of a metal-independent glycosyltransferase GT6 from Bacteroides ovatus with UDP-N-acetylgalactosamine (UDP-GalNAc) and its hydrolysis products.

    Science.gov (United States)

    Pham, Tram T K; Stinson, Brittany; Thiyagarajan, Nethaji; Lizotte-Waniewski, Michelle; Brew, Keith; Acharya, K Ravi

    2014-03-21

    Mammalian members of glycosyltransferase family 6 (GT6) of the CAZy database have a GT-A fold containing a conserved Asp-X-Asp (DXD) sequence that binds an essential metal cofactor. Bacteroides ovatus GT6a represents a GT6 clade found in more than 30 Gram-negative bacteria that is similar in sequence to the catalytic domains of mammalian GT6, but has an Asn(95)-Ala-Asn(97) (NXN) sequence substituted for the DXD motif and metal-independent catalytic activity. Co-crystals of a low activity mutant of BoGT6a (E192Q) with UDP-GalNAc contained protein complexes with intact UDP-GalNAc and two forms with hydrolysis products (UDP plus GalNAc) representing an initial closed complex and later open form primed for product release. Two cationic residues near the C terminus of BoGT6a, Lys(231) and Arg(243), interact with the diphosphate moiety of UDP-GalNAc, but only Lys(231) interacts with the UDP product and may function in leaving group stabilization. The amide group of Asn(95), the first Asn of the NXN motif, interacts with the ribose moiety of the substrate. This metal-independent GT6 resembles its metal-dependent homologs in undergoing conformational changes on binding UDP-GalNAc that arise from structuring the C terminus to cover this substrate. It appears that in the GT6 family, the metal cofactor functions specifically in binding the UDP moiety in the donor substrate and transition state, actions that can be efficiently performed by components of the polypeptide chain.

  1. The symbiotic bacterial surface factor polysaccharide A on Bacteroides fragilis inhibits IL-1β-induced inflammation in human fetal enterocytes via toll receptors 2 and 4.

    Directory of Open Access Journals (Sweden)

    Fei Jiang

    Full Text Available Colonizing bacteria interacting with the immature, unlike the mature, human intestine favors inflammation over immune homeostasis. As a result, ten percent of premature infants under 1500 grams weight develop an inflammatory necrosis of the intestine after birth, e.g., necrotizing enterocolitis (NEC. NEC is a major health problem in this population causing extensive morbidity and mortality and an enormous expenditure of health care dollars. NEC can be prevented by giving preterm infants their mother's expressed breast milk or ingesting selective probiotic organisms. Vaginally delivered, breast fed newborns develop health promoting bacteria ("pioneer" bacteria which preferentially stimulate intestinal host defense and anti-inflammation. One such "pioneer" organism is Bacteroides fragilis with a polysaccharide (PSA on its capsule. B. fragilis has been shown developmentally in intestinal lymphocytes and dendritic cells to produce a balanced T-helper cell (TH1/TH2 response and to reduce intestinal inflammation by activity through the TLR2 receptor stimulating IL-10 which inhibits IL-17 causing inflammation. No studies have been done on the role of B. fragilis PSA on fetal enterocytes and its increased inflammation. Accordingly, using human and mouse fetal intestinal models, we have shown that B. fragilis with PSA and PSA alone inhibits IL-1β-induced IL-8 inflammation in fetal and NEC intestine. We have also begun to define the mechanism for this unique inflammation noted in fetal intestine. We have shown that B. fragilis PSA anti-inflammation requires both the TLR2 and TLR4 receptor and is in part mediated by the AP1 transcription factor (TLR2 which is developmentally regulated. These observations may help to devise future preventative treatments of premature infants against NEC.

  2. Effects of Diet on Resource Utilization by a Model Human Gut Microbiota Containing Bacteroides cellulosilyticus WH2, a Symbiont with an Extensive Glycobiome

    Energy Technology Data Exchange (ETDEWEB)

    McNulty, Nathan [Washington University, St. Louis; Wu, Meng [Washington University, St. Louis; Erickson, Alison L [ORNL; Pan, Chongle [ORNL; Erickson, Brian K [ORNL; Martens, Eric C [University of Michigan; Pudlo, Nicholas A [University of Michigan; Muegge, Brian [Washington University, St. Louis; Henrissat, Bernard [Universite d' Aix-Marseille I & II; Hettich, Robert {Bob} L [ORNL; Gordon, Jeffrey [Washington University, St. Louis

    2013-01-01

    The human gut microbiota is an important metabolic organ, yet little is known about how its individual species interact, establish dominant positions, and respond to changes in environmental factors such as diet. In this study, gnotobiotic mice were colonized with an artificial microbiota comprising 12 sequenced human gut bacterial species and fed oscillating diets of disparate composition. Rapid, reproducible, and reversible changes in the structure of this assemblage were observed. Time-series microbial RNA-Seq analyses revealed staggered functional responses to diet shifts throughout the assemblage that were heavily focused on carbohydrate and amino acid metabolism. High-resolution shotgun metaproteomics confirmed many of these responses at a protein level. One member, Bacteroides cellulosilyticus WH2, proved exceptionally fit regardless of diet. Its genome encoded more carbohydrate active enzymes than any previously sequenced member of the Bacteroidetes. Transcriptional profiling indicated that B. cellulosilyticus WH2 is an adaptive forager that tailors its versatile carbohydrate utilization strategy to available dietary polysaccharides, with a strong emphasis on plant-derived xylans abundant in dietary staples like cereal grains. Two highly expressed, diet-specific polysaccharide utilization loci (PULs) in B. cellulosilyticus WH2 were identified, one with characteristics of xylan utilization systems. Introduction of a B. cellulosilyticus WH2 library comprising .90,000 isogenic transposon mutants into gnotobiotic mice, along with the other artificial community members, confirmed that these loci represent critical diet-specific fitness determinants. Carbohydrates that trigger dramatic increases in expression of these two loci and many of the organism s 111 other predicted PULs were identified by RNA-Seq during in vitro growth on 31 distinct carbohydrate substrates, allowing us to better interpret in vivo RNA-Seq and proteomics data. These results offer insight

  3. [Pharmacokinetics/pharmacodinamic (PK/PD) evaluation of a short course of oral administration of metronidazole for the management of infections caused by Bacteroides fragilis].

    Science.gov (United States)

    Morales-León, Felipe; von Plessing-Rossel, Carlos; Villa-Zapata, Lorenzo; Fernández-Rocca, Pola; Sanhueza-Sanhueza, Cindy; Bello-Toledo, Helia; Mella-Montecinos, Sergio

    2015-04-01

    Metronidazole is the antibiotic of choice for the management of infections caused by anaerobes. Its administration requires multiple daily doses causing increased medication errors. Due to its high post-antibiotic effect and rapid concentration-dependent bactericidal activity, administration of this antibiotic in an extended dosing interval would achieve PK/PD parameters effectively. To assess the probability of achieving effective PK/PD relationship with the administration of 1,000 mg every 24 hours of metronidazole for Bacteroides fragilis infections. A clinical trial was conducted in a group of volunteers who received a single oral dose of 500 or 1,000 mg of metronidazole. Determinations of values of Cmax, t max, and AUCC0-24 h. determined using the trapezoidal method, were obtained for a Markov simulation that would allow for determining the likelihood of achieving a AUC0-24 h/MIC ratio above 70 for infections caused by susceptible B. fragilis. Cmax (24,03 ± 6,89 mg/L) and t max (1,20 ± 0.80 hrs) and the value of AUC0-24 h (241.91 ± 48.14 mg * h/L) were determined. The probability of obtaining a AUC0-24 h/MIC ratio greater than 70 was greater than 99%. From a pharmacokinetic perspective, with the administration of a daily dose of 1,000 mg of metronidazole, it is possible to achieve a therapeutic goal of AUC0-24 h/MIC ratio above 70 for the treatment of anaerobic infections.

  4. Generation of a rabbit single-chain fragment variable (scFv) antibody for specific detection of Bradyrhizobium sp. DOA9 in both free-living and bacteroid forms.

    Science.gov (United States)

    Vu, Nguyen Xuan; Pruksametanan, Natcha; Srila, Witsanu; Yuttavanichakul, Watcharin; Teamtisong, Kamonluck; Teaumroong, Neung; Boonkerd, Nantakorn; Tittabutr, Panlada; Yamabhai, Montarop

    2017-01-01

    A simple and reliable method for the detection of specific nitrogen-fixing bacteria in both free-living and bacteroid forms is essential for the development and application of biofertilizer. Traditionally, a polyclonal antibody generated from an immunized rabbit was used for detection. However, the disadvantages of using a polyclonal antibody include limited supply and cross-reactivity to related bacterial strains. This is the first report on the application of phage display technology for the generation of a rabbit recombinant monoclonal antibody for specific detection and monitoring of nitrogen-fixing bacteria in both free-living form and in plant nodules. Bradyrhizobium sp. DOA9, a broad host range soil bacteria, originally isolated from the root nodules of Aeschynomene americana in Thailand was used as a model in this study. A recombinant single-chain fragment variable (scFv) antibody library was constructed from the spleen of a rabbit immunized with DOA9. After three rounds of biopanning, one specific phage-displayed scFv antibody, designated bDOA9rb8, was identified. Specific binding of this antibody was confirmed by phage enzyme-linked immunosorbent assay (phage ELISA). The phage antibody could bind specifically to DOA9 in both free-living cells (pure culture) and bacteroids inside plant nodules. In addition to phage ELISA, specific and robust immunofluorescence staining of both free-living and bacteroid forms could also be observed by confocal-immunofluorescence imaging, without cross-reactivity with other tested bradyrhizobial strains. Moreover, specific binding of free scFv to DOA9 was also demonstrated by ELISA. This recombinant antibody can also be used for the study of the molecular mechanism of plant-microbe interactions in the future.

  5. Quantitative profiling of colorectal cancer-associated bacteria reveals associations between fusobacterium spp., enterotoxigenic Bacteroides fragilis (ETBF and clinicopathological features of colorectal cancer.

    Directory of Open Access Journals (Sweden)

    Katie S Viljoen

    Full Text Available Various studies have presented clinical or in vitro evidence linking bacteria to colorectal cancer, but these bacteria have not previously been concurrently quantified by qPCR in a single cohort. We quantify these bacteria (Fusobacterium spp., Streptococcus gallolyticus, Enterococcus faecalis, Enterotoxigenic Bacteroides fragilis (ETBF, Enteropathogenic Escherichia coli (EPEC, and afaC- or pks-positive E. coli in paired tumour and normal tissue samples from 55 colorectal cancer patients. We further investigate the relationship between a the presence and b the level of colonisation of each bacterial species with site and stage of disease, age, gender, ethnicity and MSI-status. With the exception of S. gallolyticus, we detected all bacteria profiled here in both tumour and normal samples at varying frequencies. ETBF (FDR = 0.001 and 0.002 for normal and tumour samples and afaC-positive E. coli (FDR = 0.03, normal samples were significantly enriched in the colon compared to the rectum. ETBF (FDR = 0.04 and 0.002 for normal and tumour samples, respectively and Fusobacterium spp. (FDR = 0.03 tumour samples levels were significantly higher in late stage (III/IV colorectal cancers. Fusobacterium was by far the most common bacteria detected, occurring in 82% and 81% of paired tumour and normal samples. Fusobacterium was also the only bacterium that was significantly higher in tumour compared to normal samples (p = 6e-5. We also identified significant associations between high-level colonisation by Fusobacterium and MSI-H (FDR = 0.05, age (FDR = 0.03 or pks-positive E. coli (FDR = 0.01. Furthermore, we exclusively identified atypical EPEC in our cohort, which has not been previously reported in association with colorectal cancer. By quantifying colorectal cancer-associated bacteria across a single cohort, we uncovered inter- and intra-individual patterns of colonization not previously recognized, as well as important associations with clinicopathological

  6. The Fumarate Reductase of Bacteroides thetaiotaomicron, unlike That of Escherichia coli, Is Configured so that It Does Not Generate Reactive Oxygen Species.

    Science.gov (United States)

    Lu, Zheng; Imlay, James A

    2017-01-03

    The impact of oxidative stress upon organismal fitness is most apparent in the phenomenon of obligate anaerobiosis. The root cause may be multifaceted, but the intracellular generation of reactive oxygen species (ROS) likely plays a key role. ROS are formed when redox enzymes accidentally transfer electrons to oxygen rather than to their physiological substrates. In this study, we confirm that the predominant intestinal anaerobe Bacteroides thetaiotaomicron generates intracellular ROS at a very high rate when it is aerated. Fumarate reductase (Frd) is a prominent enzyme in the anaerobic metabolism of many bacteria, including B. thetaiotaomicron, and prior studies of Escherichia coli Frd showed that the enzyme is unusually prone to ROS generation. Surprisingly, in this study biochemical analysis demonstrated that the B. thetaiotaomicron Frd does not react with oxygen at all: neither superoxide nor hydrogen peroxide is formed. Subunit-swapping experiments indicated that this difference does not derive from the flavoprotein subunit at which ROS normally arise. Experiments with the related enzyme succinate dehydrogenase discouraged the hypothesis that heme moieties are responsible. Thus, resistance to oxidation may reflect a shift of electron density away from the flavin moiety toward the iron-sulfur clusters. This study shows that the autoxidizability of a redox enzyme can be suppressed by subtle modifications that do not compromise its physiological function. One implication is that selective pressures might enhance the oxygen tolerance of an organism by manipulating the electronic properties of its redox enzymes so they do not generate ROS. Whether in sediments or pathogenic biofilms, the structures of microbial communities are configured around the sensitivities of their members to oxygen. Oxygen triggers the intracellular formation of reactive oxygen species (ROS), and the sensitivity of a microbe to oxygen likely depends upon the rates at which ROS are formed

  7. Hymenobacter roseosalivarius gen. nov., sp. nov. from continental Antartica soils and sandstone: bacteria of the Cytophaga/Flavobacterium/Bacteroides line of phylogenetic descent.

    Science.gov (United States)

    Hirsch, P; Ludwig, W; Hethke, C; Sittig, M; Hoffmann, B; Gallikowski, C A

    1998-08-01

    Aseptically collected sandstone and soil samples from the antarctic Dry Valleys were inoculated into oligotrophic media and incubated under low light intensities. A total of 41 Gram-negative isolates were obtained with reddish colonies spreading on agar. A sandstone isolate and four soil strains were characterized further. They were nearly identical in morphological, physiological, biochemical and chemotaxonomic properties. They produced large amounts of extracellular polymer and utilized for growth: glucose, saccharose, mannitol, sorbitol, L-aspartate, malate and acetate, but not D-ribose, adonitol, DL-alanine, glutamate, glycolate, lactate or succinate. All strains hydrolyzed gelatin, starch, casein, xylan, Tweens 80 or 60 and dead or living yeast cells, but not cellulose or pectin. Nitrate was not reduced, ethanol was not oxidized and acid was not produced from maltose, mannitol or dulcitol. Ammonia was not produced from peptone. They were strictly aerobic. Major fatty acids were n 16:1 d 9, n 16:1 d 11, n 17:1 d 11, and i 15:0. The strains contained the quinone MK-7 and phosphatidylethanolamine as the main phospholipid. The base ratio ranged from 55 to 61 mol% G+C. A 16S rRNA sequence analysis of strains AA-688 and AA-718 showed these to be identical and to represent a special phylogenetic group within the Cytophaga/Flavobacterium/Bacteroides major line of descent. Three soil strains labeled "Taxeobacter" Txc1, Txg1, and Txo1 (Reichenbach, 1992) belonged to the same group but had lower sequence similarities (<95%). Some of their characteristics were different from those of the antarctic strains: the utilization of C-compounds, hydrolysis of polymers, temperature tolerances, major fatty acids and base ratios. Txc1 and Txg1 may later have to be considered as members of this group, possibly on the species level, while Txo1 could represent a different related genus. It is concluded that the five antarctic strains represent a new genus and species for which the name

  8. Detection of Bacteroides forsythus and Porphyromonas gingivalis in ...

    African Journals Online (AJOL)

    STORAGESEVER

    2009-05-18

    May 18, 2009 ... periodontitis among Chinese patients. 217 patients with chronic periapcial periodontitis were recruited and a total of 266 teeth were collected. The subjects had no systemic diseases, no antibiotics taken, no root canal treatment (RCT) performed on the infected teeth in the last 3 months. The DNA of bacteria ...

  9. Xylose metabolism in Bacteroides xylanolyticus X5-1

    NARCIS (Netherlands)

    Biesterveld, S.

    1994-01-01

    Plant cell walls represent a major part of the available biomass on earth. They are mainly composed of the energy-rich polymers lignin, cellulose, and hemicellulose. For many decades, research is done to exploit agricultural and forestry wastes as renewable resources. Much research was

  10. Detection of Bacteroides forsythus and Porphyromonas gingivalis in ...

    African Journals Online (AJOL)

    24 out of 217 infected root canals demonstrated the existence of both types of bacteria, the utility of a 16S rDNA-based PCR detection method showed high sensitivity and high specificity to directly detect B. forsythus, P. gingivalis or other pulpal microorganisms from samples of root canal infections. The results indicated that ...

  11. Xylan degradation by the anaerobic bacterium Bacteroides xylanolyticus

    NARCIS (Netherlands)

    Schyns, P.J.Y.M.L.

    1997-01-01

    Plant cell walls are the major reservoir of fixed carbon in nature. The mineralization of the fiber material, the so called lignocellulosic complex, proceeds almost exclusively by microbial processes in both aerobic and anaerobic environments. In anaerobic microbial processes the energy of

  12. Effect of hyperbaric air on endotoxin from Bacteroides fragilis strains

    Czech Academy of Sciences Publication Activity Database

    Chmelař, D.; Kašíková, A.; Martineková, P.; Hájek, M.; Rozložník, M.; Brabec, Marek; Janečková, J.; Vobejdová, J.; Čižnár, I.

    2018-01-01

    Roč. 63, č. 3 (2018), s. 283-290 ISSN 0015-5632 Institutional support: RVO:67985807 Keywords : endotoxin * hyperbaric condition Subject RIV: EE - Microbiology, Virology Impact factor: 1.521, year: 2016

  13. Bacteroides forsythus: sensibilidade a antimicrobianos em amostras de pacientes portadores de periodontite Bacteroides forsythus: sensitivity to antimicrobial agents in samples from patients with periodontitis

    Directory of Open Access Journals (Sweden)

    Roberto Fraga Moreira LOTUFO

    2001-03-01

    Full Text Available Os autores realizaram teste de sensibilidade antimicrobiana in vitro (técnica de diluição em ágar para 105 cepas de B. forsythus obtidas de pacientes portadores de periodontite. De acordo com o teste realizado, o microrganismo demonstrou ser sensível ao metronidazol (100% das cepas testadas e à amoxicilina (94% das cepas testadas, enquanto 72% e 65% das cepas foram susceptíveis à tetraciclina e ciprofloxacina, respectivamente. O metronidazol e a amoxicilina parecem ser os antimicrobianos indicados para o tratamento de infecções periodontais nas quais B. forsythus seja o patógeno predominante.An in vitro antimicrobial sensitivity test (technique of agar dilution was carried out for 105 clinical isolates of B. forsythus from patients with periodontitis. Metronidazole and amoxicillin were the most efficient drugs and, thus, are indicated for the treatment of periodontal infections in which this microorganism is the most prevalent pathogen.

  14. Bacteroides Fragilis OmpA: Utility as a Live Vaccine Vector for Biodefense Agents

    Science.gov (United States)

    2009-01-01

    carbapenems (doripenem, ertapenem, faropenem, imipenem, meropenem), quinolones (ciprofloxacin, gatifloxacin, norfloxacin , levofloxacin, moxifloxacin...extractions were combined and redialyzed against buffer containing 20 mM Tris–HCL and 3 mM sodium azide for 4 days at room temperature, with frequent...gatifloxacin, norfloxacin , levofloxacin, 298 13 moxifloxacin), chloramphenicol, metronidazole, clindamycin, erythromycin and tetracycline. No

  15. Levan Enhances Associated Growth of Bacteroides, Escherichia, Streptococcus and Faecalibacterium in Fecal Microbiota

    DEFF Research Database (Denmark)

    Adamberg, Kaarel; Tomson, Katrin; Talve, Tiina

    2015-01-01

    The role of dietary fiber in supporting healthy gut microbiota and overall well-being of the host has been revealed in several studies. Here, we show the effect of a bacterial polyfructan levan on the growth dynamics and metabolism of fecal microbiota in vitro by using isothermal microcalorimetry....... Eleven fecal samples from healthy donors were incubated in phosphate-buffered defined medium with or without levan supplementation and varying presence of amino acids. The generation of heat, changes in pH and microbiota composition, concentrations of produced and consumed metabolites during the growth...

  16. Effects of ultraviolet radiation on the survival and metabolic end products of Bacteroides melaninogenicus

    Energy Technology Data Exchange (ETDEWEB)

    Smith-Kappus, S.D.

    1987-01-01

    In experiments investigating DNA repair, it was shown that B. melaninogenicus does not repair UV light induced damage via photoreactivation. Survival curves constructed for the organism after exposure to UV light at 254 nm and 365 nm under aerobic and anaerobic conditions while the organisms were in exponential or stationary growth phase, revealed that the cells were most sensitive to UV induced damage when exposed to radiation while in the exponential growth phase under aerobic conditions at either wavelength. B. melaninogenicus exposed to UV light under anaerobic conditions while the cells were in stationary growth phase were much more sensitive to UV induced damage at 254 nm than cells irradiated under the same conditions at 365 nm UV. Survival studies of B. melaninogenicus after co-insult with UV light and subinhibitory concentrations of chloramphenicol, metronidazole, caffeine, or fluoroacetate, at 254 nm UV or 365 nm UV, under aerobic and anaerobic atmospheric conditions illustrated a decreased shoulder region on the curves, particularly after 365 nm UV exposure, when compared to UV irradiation applied without subsequent chemical treatment.

  17. In vivo and in vitro anti-inflammatory activity of components isolated from Bacteroides distasonis

    Czech Academy of Sciences Publication Activity Database

    Zákostelská, Zuzana; Kverka, Miloslav; Sokol, D.; Klimešová, Klára; Hudcovic, Tomáš; Hrnčíř, Tomáš; Rossmann, Pavel; Mrázek, Jakub; Kopečný, Jan; Tlaskalová, Helena

    2009-01-01

    Roč. 39, - (2009), s. 699-699 ISSN 0014-2980. [European Congress of Immunology /2./. 13.09.2009-16.09.2009, Berlin] Institutional research plan: CEZ:AV0Z50200510; CEZ:AV0Z50450515 Keywords : colitis * intestinal inflamation Subject RIV: EC - Immunology

  18. Effects of ultraviolet radiation on the survival and metabolic end products of Bacteroides melaninogenicus

    International Nuclear Information System (INIS)

    Smith-Kappus, S.D.

    1987-01-01

    In experiments investigating DNA repair, it was shown that B. melaninogenicus does not repair UV light induced damage via photoreactivation. Survival curves constructed for the organism after exposure to UV light at 254 nm and 365 nm under aerobic and anaerobic conditions while the organisms were in exponential or stationary growth phase, revealed that the cells were most sensitive to UV induced damage when exposed to radiation while in the exponential growth phase under aerobic conditions at either wavelength. B. melaninogenicus exposed to UV light under anaerobic conditions while the cells were in stationary growth phase were much more sensitive to UV induced damage at 254 nm than cells irradiated under the same conditions at 365 nm UV. Survival studies of B. melaninogenicus after co-insult with UV light and subinhibitory concentrations of chloramphenicol, metronidazole, caffeine, or fluoroacetate, at 254 nm UV or 365 nm UV, under aerobic and anaerobic atmospheric conditions illustrated a decreased shoulder region on the curves, particularly after 365 nm UV exposure, when compared to UV irradiation applied without subsequent chemical treatment

  19. Differential metabolism of Exopolysaccharides from probiotic Lactobacilli by the human gut symbiont Bacteroides thetaiotaomicron

    NARCIS (Netherlands)

    Lammerts van Bueren, Alica; Saraf, Aakanksha; Martens, Eric C; Dijkhuizen, Lubbert

    2015-01-01

    Probiotic microorganisms are ingested as food or supplements and impart positive health benefits to consumers. Previous studies have indicated that probiotics transiently reside in the gastrointestinal tract and in addition to modulating commensal species diversity, also increase the expression of

  20. Antimicrobial resistance in the Bacteroides fragilis group in faecal microbiota from healthy Danish children

    DEFF Research Database (Denmark)

    Sydenham, Thomas Vognbjerg; Jensen, Betina Hebbelstrup; Petersen, Andreas Munk

    2017-01-01

    of relatively antibiotic-naive healthy Danish children. From 174 faecal samples collected from children attending day care, 359 non-duplicate isolates were screened for antimicrobial susceptibility. Of these, 0.0%, 1.9%, 5.0% and 21.2% of isolates were intermediate-susceptible or resistant to metronidazole...

  1. Unique organization and unprecedented diversity of the Bacteroides (Pseudobacteroides) cellulosolvens cellulosome system

    Energy Technology Data Exchange (ETDEWEB)

    Zhivin, Olga; Dassa, Bareket; Moraïs, Sarah; Utturkar, Sagar M.; Brown, Steven D.; Henrissat, Bernard; Lamed, Raphael; Bayer, Edward A.

    2017-09-07

    The organization of the B. cellulosolvens cellulosome is unique compared to previously described cellulosome systems. In contrast to all other known cellulosomes, the cohesin types are reversed for all scaffoldins i.e., the type II cohesins are located on the enzyme-integrating primary scaffoldin, whereas the type I cohesins are located on the anchoring scaffoldins. Many of the type II dockerin-bearing ORFs include X60 modules, which are known to stabilize type II cohesin–dockerin interactions. In the present work, we focused on revealing the architectural arrangement of cellulosome structure in this bacterium by examining numerous interactions between the various cohesin and dockerin modules. In total, we cloned and expressed 43 representative cohesins and 27 dockerins. The results revealed various possible architectures of cell-anchored and cell-free cellulosomes, which serve to assemble distinctive cellulosome types via three distinct cohesin–dockerin specificities: type I, type II, and a novel-type designated R (distinct from type III interactions, predominant in ruminococcal cellulosomes). The results of this study provide novel insight into the architecture and function of the most intricate and extensive cellulosomal system known today, thereby extending significantly our overall knowledge base of cellulosome systems and their components. The robust cellulosome system of B. cellulosolvens, with its unique binding specificities and reversal of cohesin–dockerin types, has served to amend our view of the cellulosome paradigm. Revealing new cellulosomal interactions and arrangements is critical for designing high-efficiency artificial cellulosomes for conversion of plant-derived cellulosic biomass towards improved production of biofuels.

  2. Dietary pectic glycans are degraded by coordinated enzyme pathways in human colonic Bacteroides

    DEFF Research Database (Denmark)

    Luis, Ana S.; Briggs, Jonathon; Zhang, Xiaoyang

    2018-01-01

    the remnants of other pectin domains attached to rhamnogalacturonan-I, and nine enzymes that contribute to the degradation of the backbone that makes up a rhamnose-GalA repeating unit. The catalytic properties of the pectin-degrading enzymes are optimized to protect the glycan cues that activate the specific...

  3. The gut bacterium Bacteroides thetaiotaomicron influences the virulence potential of the enterohemorrhagic Escherichia coli O103:H25.

    Directory of Open Access Journals (Sweden)

    Hildegunn Iversen

    Full Text Available Enterohemorrhagic E. coli (EHEC is associated with severe gastrointestinal disease. Upon entering the gastrointestinal tract, EHEC is exposed to a fluctuating environment and a myriad of other bacterial species. To establish an infection, EHEC strains have to modulate their gene expression according to the GI tract environment. In order to explore the interspecies interactions between EHEC and an human intestinal commensal, the global gene expression profile was determined of EHEC O103:H25 (EHEC NIPH-11060424 co-cultured with B. thetaiotaomicron (CCUG 10774 or grown in the presence of spent medium from B. thetaiotaomicron. Microarray analysis revealed that approximately 1% of the EHEC NIPH-11060424 genes were significantly up-regulated both in co-culture (30 genes and in the presence of spent medium (44 genes, and that the affected genes differed between the two conditions. In co-culture, genes encoding structural components of the type three secretion system were among the most affected genes with an almost 4-fold up-regulation, while the most affected genes in spent medium were involved in chemotaxis and were more than 3-fold up-regulated. The operons for type three secretion system (TTSS are located on the Locus of enterocyte effacement (LEE pathogenicity island, and qPCR showed that genes of all five operons (LEE1-LEE5 were up-regulated. Moreover, an increased adherence to HeLa cells was observed in EHEC NIPH-11060424 exposed to B. thetaiotaomicron. Expression of stx2 genes, encoding the main virulence factor of EHEC, was down-regulated in both conditions (co-culture/spent medium. These results show that expression of EHEC genes involved in colonization and virulence is modulated in response to direct interspecies contact between cells, or to diffusible factors released from B. thetaiotaomicron. Such interspecies interactions could allow the pathogen to recognize its predilection site and modulate its behaviour accordingly, thus increasing the efficiency of colonization of the colon mucosa, facilitating its persistence and increasing its virulence potential.

  4. Antimicrobial resistance in the Bacteroides fragilis group in faecal samples from patients receiving broad-spectrum antibiotics

    DEFF Research Database (Denmark)

    Møller Hansen, Kia Cirkeline; Ferløv-Schwensen, Simon Andreas; Henriksen, Daniel Pilsgaard

    2017-01-01

    the prevalence of the carbapenem resistance gene cfiA in B. fragilis in this patient group, and 3) to determine the association between previous antibiotic treatment and reduced susceptibility to clindamycin, meropenem, metronidazole, and piperacillin-tazobactam. Consecutive faecal samples (n = 197) were...

  5. Medicago truncatula ENOD40-1 and ENOD40-2 are both involved in nodule initiation and bacteroid development

    NARCIS (Netherlands)

    Wan, X.; Hontelez, J.; Lillo, A.; Guarnerio, C.; Peut, van de D.; Fedorova, E.; Bisseling, T.; Franssen, H.

    2007-01-01

    The establishment of a nitrogen-fixing root nodule on legumes requires the induction of mitotic activity of cortical cells leading to the formation of the nodule primordium and the infection process by which the bacteria enter this primordium. Several genes are up-regulated during these processes,

  6. A novel glycoside hydrolase family 97 enzyme: Bifunctional β-l-arabinopyranosidase/α-galactosidase from Bacteroides thetaiotaomicron.

    Science.gov (United States)

    Kikuchi, Asako; Okuyama, Masayuki; Kato, Koji; Osaki, Shohei; Ma, Min; Kumagai, Yuya; Matsunaga, Kana; Klahan, Patcharapa; Tagami, Takayoshi; Yao, Min; Kimura, Atsuo

    2017-11-01

    Glycoside hydrolase family 97 (GH97) is one of the most interesting glycosidase families, which contains inverting and retaining glycosidases. Currently, only two enzyme types, α-glucoside hydrolase and α-galactosidase, are registered in the carbohydrate active enzyme database as GH97 function-known proteins. To explore new specificities, BT3661 and BT3664, which have distinct amino acid sequences when compared with that of GH97 α-glucoside hydrolase and α-galactosidase, were characterized in this study. BT3664 was identified to be an α-galactosidase, whereas BT3661 exhibits hydrolytic activity toward both β-l-arabinopyranoside and α-d-galactopyranoside, and thus we designate BT3661 as a β-l-arabinopyranosidase/α-d-galactosidase. Since this is the first dual substrate specificity enzyme in GH97, we investigated the substrate recognition mechanism of BT3661 by determining its three-dimensional structure and based on this structural data generated a number of mutants to probe the enzymatic mechanism. Structural comparison shows that the active-site pocket of BT3661 is similar to GH97 α-galactosidase BT1871, but the environment around the hydroxymethyl group of the galactopyranoside is different. While BT1871 bears Glu361 to stabilize the hydroxy group of C6 through a hydrogen bond with its carboxy group, BT3661 has Asn338 at the equivalent position. Amino acid mutation analysis indicates that the length of the side chain at Asn338 is important for defining specificity of BT3661. The k cat /K m value for the hydrolysis of p-nitrophenyl α-galactoside decreases when Asn338 is substituted with Glu, whereas an increase is observed when the mutation is Ala. Interestingly, mutation of Asn338 to Ala reduces the k cat /K m value for hydrolysis of p-nitrophenyl β-l-arabinopyranoside. Copyright © 2017. Published by Elsevier B.V.

  7. Relationships and trends of E. Coli, human-associated bacteroides, and pathogens in the Proctor Creek watershed (GWRC 2017)

    Science.gov (United States)

    Urban surface waters can be impacted by anthropogenic sources such as impervious surfaces, sani-tary and storm sewers, and failing infrastructure. Fecal indicator bacteria (FIB) and microbial source tracking (MST) markers are common gauges of stream water qual-ity, however, litt...

  8. Relationships and trends of E. Coli, human-associated Bacteroides, and pathogens in the Proctor Creek Watershed

    Science.gov (United States)

    Urban surface waters can be impacted by anthropogenic sources such as impervious surfaces, sanitary and storm sewers, and failing infrastructure. Fecal indicator bacteria (FIB) and microbial source tracking (MST) markers are common gauges of stream water quality, however, little...

  9. Aquiflexum balticum gen. nov., sp. nov., a novel marine bacterium of the Cytophaga-Flavobacterium-Bacteroides group isolated from surface water of the central Baltic Sea.

    Science.gov (United States)

    Brettar, Ingrid; Christen, Richard; Höfle, Manfred G

    2004-11-01

    A bacterial isolate from the Baltic Sea, BA160(T), was characterized for its physiological and biochemical features, fatty acid profile, G+C content and phylogenetic position based on 16S rRNA gene sequences. The strain was isolated from the surface water of the central Baltic Sea during the decay of a plankton bloom. Phylogenetic analyses of the 16S rRNA gene sequence revealed a clear affiliation with the family 'Flexibacteraceae', and showed the closest phylogenetic relationship with the species Belliella baltica and Cyclobacterium marinum. The G+C content of the DNA was 38.4 mol%. The strain was red-coloured due to carotenoids, Gram-negative, rod-shaped, and catalase- and oxidase-positive. Growth was observed at salinities from 0 to 6 %, with an optimum around 1.5 %. Temperature for growth ranged from 4 to 40 degrees C, with an optimum around 30 degrees C. The fatty acids were dominated by branched-chain fatty acids (>87 %), with a high abundance of iso-C(15 : 0) (23 %) and anteiso-C(15 : 0) (19 %). According to its morphology, physiology, fatty acid composition, G+C content and 16S rRNA gene sequence, strain BA160(T) is considered to represent a new genus of the family 'Flexibacteraceae'. Due to its aquatic origin, the name Aquiflexum balticum gen. nov, sp. nov. is suggested for the type species (type strain, BA160(T)=DSM 16537(T)=LMG 22565(T)=CIP 108445(T)) of the new genus.

  10. Effects of DNA Extraction Procedures on Bacteroides Profiles in Fecal Samples From Various Animals Determined by Terminal Restriction Fragment Length Polymorphism Analysis

    Science.gov (United States)

    A major assumption in microbial source tracking is that some fecal bacteria are specific to a host animal, and thus provide unique microbial fingerprints that can be used to differentiate hosts. However, the DNA information obtained from a particular sample may be biased dependi...

  11. Overexpression of flavodoxin in bacteroids induces changes in antioxidant metabolism leading to delayed senescence and starch accumulation in alfalfa root nodules.

    Science.gov (United States)

    Redondo, Francisco J; de la Peña, Teodoro Coba; Morcillo, César N; Lucas, M Mercedes; Pueyo, José J

    2009-02-01

    Sinorhizobium meliloti cells were engineered to overexpress Anabaena variabilis flavodoxin, a protein that is involved in the response to oxidative stress. Nodule natural senescence was characterized in alfalfa (Medicago sativa) plants nodulated by the flavodoxin-overexpressing rhizobia or the corresponding control bacteria. The decline of nitrogenase activity and the nodule structural and ultrastructural alterations that are associated with nodule senescence were significantly delayed in flavodoxin-expressing nodules. Substantial changes in nodule antioxidant metabolism, involving antioxidant enzymes and ascorbate-glutathione cycle enzymes and metabolites, were detected in flavodoxin-containing nodules. Lipid peroxidation was also significantly lower in flavodoxin-expressing nodules than in control nodules. The observed amelioration of the oxidative balance suggests that the delay in nodule senescence was most likely due to a role of the protein in reactive oxygen species detoxification. Flavodoxin overexpression also led to high starch accumulation in nodules, without reduction of the nitrogen-fixing activity.

  12. Detection of Increased Plasma Interleukin-6 Levels and Prevalence of Prevotella copri and Bacteroides vulgatus in the Feces of Type 2 Diabetes Patients

    OpenAIRE

    Leite, Aline Zazeri; Rodrigues, Nathália de Campos; Gonzaga, Marina Ignácio; Paiolo, João Carlos Cicogna; de Souza, Carolina Arantes; Stefanutto, Nadine Aparecida Vicentini; Omori, Wellington Pine; Pinheiro, Daniel Guariz; Brisotti, João Luiz; Matheucci Junior, Euclides; Mariano, Vânia Sammartino; de Oliveira, Gislane Lelis Vilela

    2017-01-01

    Intestinal dysbiosis and metabolic endotoxemia have been associated with metabolic disorders, such as obesity, insulin resistance, and type 2 diabetes (T2D). The main goal of the present study was to evaluate the intestinal dysbiosis in Brazilian T2D patients and correlate these data with inflammatory cytokines and lipopolysaccharides (LPS) plasma concentrations. This study was approved by the Ethics Committees from Barretos Cancer Hospital and all individuals signed the informed consent form...

  13. G protein-coupled receptor 120 (GPR120) transcription in intestinal epithelial cells is significantly affected by bacteria belonging to the Bacteroides, Proteobacteria, and Firmicutes phyla

    DEFF Research Database (Denmark)

    Fredborg, Marlene; Theil, Peter Kappel; Jensen, Bent Borg

    2012-01-01

    examined using real-time reverse transcriptase polymerase chain reaction. The abundance of GLP-1 mRNA decreased when cells were exposed to 4 of the 12 supernatants (P ≤ 0.05) compared with cells without bacteria added. Supernatants from 8 of the 12 bacteria analyzed increased the mRNA level of GPR120 (P...

  14. A highly active endo-levanase BT1760 of a dominant mammalian gut commensal Bacteroides thetaiotaomicron cleaves not only various bacterial levans, but also levan of timothy grass

    DEFF Research Database (Denmark)

    Mardo, Karin; Visnapuu, Triinu; Vija, Heiki

    2017-01-01

    -levanase BT1760. The FOS are consumed by B. thetaiotaomicron, but also by other gut bacteria, including health-promoting bifidobacteria and lactobacilli. Here we characterize biochemical properties of BT1760, including the activity of BT1760 on six bacterial levans synthesized by the levansucrase Lsc3...

  15. Detection of Staphylococcus Aureus Enterotoxin A and B Genes with PCR-EIA and a Hand-Held Electrochemical Sensor

    National Research Council Canada - National Science Library

    Aitichou, Mohamed; Henkins, Robert; Sultana, Afroz M; Ulrich, Robert G; Ibrahim, M. S

    2004-01-01

    ... S. aureus DNA, and genomic DNA from Alcaligens, Bacillus, Bacteroides, Bordetella, Burkholderia, Clostridium, Comanonas, Enterobacter, Enterococcus, Escherichia, Francisella, Haemophilus, Klebsiella...

  16. Detection of B. fragilis group and diversity of bft enterotoxin and antibiotic resistance markers cepA, cfiA and nim among intestinal Bacteroides fragilis strains in patients with inflammatory bowel disease.

    Science.gov (United States)

    Rashidan, Marjan; Azimirad, Masoumeh; Alebouyeh, Masoud; Ghobakhlou, Mehdi; Asadzadeh Aghdaei, Hamid; Zali, Mohammad Reza

    2018-04-01

    We compared frequency of the members of B. fragilis group in 100 and 20 colon biopsy specimens of inflammatory bowel disease (IBD) and non-IBD patients. Agar dilution and PCR were orderly used to detect minimal inhibitory concentration of ampicillin, imipenem, and metronidazole, and carriage of related resistance genes cepA, cfi, and nim. B. fragilis group was detected in 38% of IBD (UC: 36/89; CD:1/11) and 25% (5/20) of non-IBD patients. While B. vulgatus (UC: 20/36, CD: 1/2, control: 1/6); B. fragilis (UC: 18/36, CD: 1/2, control: 5/6); B. ovatus (UC: 2/36); B. caccae (UC: 1/36); and B. eggerthii (UC: 1/36) were characterized, colonization of B. thetaiotamicron, B. merdae, B. distasonis, B. stercoris and B. dorei species was not detected in these specimens. Co-existence of B. fragilis + B. vulgatus (5 patients) and B. vulgatus + B. caccae (1 patient) was detected just in UC patients. bft was detected among 31.5% (6/19) of B. fragilis strains in the IBD and 40% (2/5) in the non-IBD groups. Nearly, 73.6% of the strains from the patient group and 80% in control group harbored cepA; 31.5% and 20% in the patients and control groups harbored cfiA, and none of them harbored nim determinant. Co-occurrence of the cepA and cfiA was orderly detected in 10.5% (2/19) and 20% (1/5) of the strains in these groups. The resistance rates were detected as 95.8% (23/24 (to ampicillin (MIC range of ≤0.5-≥16 μg/ml), 0% to metronidazole and 29.1% to imipenem (7/24, MIC range ≤4-32 μg/ml). Nearly 25% (6/24) of the strains were resistant to ampicillin and imipenem, simultaneously. No statistically significant difference was detected between the IBD and control groups for drug resistance phenotypes. Statistical analysis showed significant associations between resistance to ampicillin or imipenem and carriage of cepA or cfiA, respectively (p value = 0.0007). PCR results on the extracted plasmids confirmed their roles in carriage of cfiA and cepA. These data provide guide for antibiotic therapy and highlights wide distribution of β-lactam resistant B. fragilis strains in patients with IBD and non-IBD intestinal disorders. Copyright © 2018 Elsevier Ltd. All rights reserved.

  17. ORF Alignment: NC_003228 [GENIUS II[Archive

    Lifescience Database Archive (English)

    Full Text Available oamide ... acetyltransferase [Bacteroides fragilis NCTC 9343] ... Length = 227 ... Query: 229 KEMDR...VRRIIADHMVMSKKVSPHVTNVVEVDVTRLVRWREKTKDAFFRREGVKLTYMPXX 288 ... KEMDRVRR...IIADHMVMSKKVSPHVTNVVEVDVTRLVRWREKTKDAFFRREGVKLTYMP ... Sbjct: 3 ... KEMDRVRRIIADHMVMSKKVSPHVTNVVEVDVTRLVRWREKTKD

  18. ORF Alignment: NC_006347 [GENIUS II[Archive

    Lifescience Database Archive (English)

    Full Text Available ide ... interchange protein [Bacteroides fragilis YCH46] ... Length = 140 ... Query: 401 NNQPKTGNRFID...FSAPDLNGNMVQLSEQIRGKVALIDLWASWCGPCRTTSKQLIPIYEKY 460 ... NNQPKTGNRFIDF...SAPDLNGNMVQLSEQIRGKVALIDLWASWCGPCRTTSKQLIPIYEKY Sbjct: 1 ... NNQPKTGNRFIDFSAPDLNGNMVQLSEQIRGKVALIDLWASWCGPCRTT

  19. ORF Alignment: NC_003228 [GENIUS II[Archive

    Lifescience Database Archive (English)

    Full Text Available ide ... interchange protein [Bacteroides fragilis YCH46] ... Length = 140 ... Query: 401 NNQPKTGNRFID...FSAPDLNGNMVQLSEQIRGKVALIDLWASWCGPCRTTSKQLIPIYEKY 460 ... NNQPKTGNRFIDF...SAPDLNGNMVQLSEQIRGKVALIDLWASWCGPCRTTSKQLIPIYEKY Sbjct: 1 ... NNQPKTGNRFIDFSAPDLNGNMVQLSEQIRGKVALIDLWASWCGPCRTT

  20. ORF Alignment: NC_006347 [GENIUS II[Archive

    Lifescience Database Archive (English)

    Full Text Available ... [Bacteroides fragilis NCTC 9343] ... Length = 167 ... Query: 5 ... VFGAAVQGIEATLITIEVNSSRGCMFYMVGLPDSAVKESHQRILSALQVTGYKMPTS...NIV 64 ... VFGAAVQGIEATLITIEVNSSRGCMFYMVGLPDSAVKESHQRILSALQVTGYKMPTS...NIV Sbjct: 1 ... VFGAAVQGIEATLITIEVNSSRGCMFYMVGLPDSAVKESHQRILSALQVTGYKMPTSNIV 60 ... Query: 125

  1. ORF Alignment: NC_003228 [GENIUS II[Archive

    Lifescience Database Archive (English)

    Full Text Available ... [Bacteroides fragilis NCTC 9343] ... Length = 167 ... Query: 5 ... VFGAAVQGIEATLITIEVNSSRGCMFYMVGLPDSAVKESHQRILSALQVTGYKMPTS...NIV 64 ... VFGAAVQGIEATLITIEVNSSRGCMFYMVGLPDSAVKESHQRILSALQVTGYKMPTS...NIV Sbjct: 1 ... VFGAAVQGIEATLITIEVNSSRGCMFYMVGLPDSAVKESHQRILSALQVTGYKMPTSNIV 60 ... Query: 125

  2. ORF Alignment: NC_006347 [GENIUS II[Archive

    Lifescience Database Archive (English)

    Full Text Available L9 ... [Bacteroides fragilis NCTC 9343] ... Length = 147 ... Query: 1 ... MEIILKEDVVNLGYKNDIVTVKSGYGRNYLIPTGKAVIASP...SAKKMLAEELKQRAHKLEK 60 ... MEIILKEDVVNLGYKNDIVTVKSGYGRNYLIPTGKAVIASP...SAKKMLAEELKQRAHKLEK Sbjct: 1 ... MEIILKEDVVNLGYKNDIVTVKSGYGRNYLIPTGKAVIASPSAKKMLAEELKQRAHKLEK 60 ... Qu

  3. ORF Alignment: NC_004663 [GENIUS II[Archive

    Lifescience Database Archive (English)

    Full Text Available ... [Bacteroides thetaiotaomicron VPI-5482] ... Length = 105 ... Query: 449 VLQDQSLQKEASTGYGRLYDFFKHNFNYLMKYAGNLFAQKRYDEAIVILER...AKLVSCHPS 508 ... VLQDQSLQKEASTGYGRLYDFFKHNFNYLMKYAGNLFAQKRYDEAIVILER...AKLVSCHPS Sbjct: 1 ... VLQDQSLQKEASTGYGRLYDFFKHNFNYLMKYAGNLFAQKRYDEAIVILERAKLVSCHPS 60 ...

  4. ORF Alignment: NC_006347 [GENIUS II[Archive

    Lifescience Database Archive (English)

    Full Text Available rotein [Bacteroides ... fragilis NCTC 9343] ... Length = 118 ... Query: 437 SDKKLSILVA...EDMEDNYRLCEAILASRYELHWAHNGEEAISLFLKFQPDIILMDIRMPEV 496 ... SDKKLSILVAEDMEDNYRLCEAILAS...RYELHWAHNGEEAISLFLKFQPDIILMDIRMPEV Sbjct: 1 ... SDKKLSILVAEDMEDNYRLCEAILASRYELHWAHNGEEAISLFLKFQPDIILMDIRMPEV 60 ...

  5. ORF Alignment: NC_003228 [GENIUS II[Archive

    Lifescience Database Archive (English)

    Full Text Available rotein [Bacteroides ... fragilis NCTC 9343] ... Length = 118 ... Query: 437 SDKKLSILVA...EDMEDNYRLCEAILASRYELHWAHNGEEAISLFLKFQPDIILMDIRMPEV 496 ... SDKKLSILVAEDMEDNYRLCEAILAS...RYELHWAHNGEEAISLFLKFQPDIILMDIRMPEV Sbjct: 1 ... SDKKLSILVAEDMEDNYRLCEAILASRYELHWAHNGEEAISLFLKFQPDIILMDIRMPEV 60 ...

  6. Characterisation by proteomics of peribacteroid space and peribacteroid membrane preparations from pea (¤Pisum sativum¤) symbiosomes

    DEFF Research Database (Denmark)

    Saalbach, G.; Erik, P.; Wienkoop, S.

    2002-01-01

    The legume Rhizobium symbiosis leads to the formation of a new compartment in the plant cell, the symbiosome. This compartment harbours the bacteroids surrounded by a peribacteroid membrane (PBM) originating from the plant plasma membrane. The PBM and the space between the PBM and the bacteroid...

  7. Molecular docking studies on rocaglamide, a traditional Chinese ...

    African Journals Online (AJOL)

    involved in the infection leading to periodontitis are Bacteroides gingivalis, Bacteroides intermedius and Actinobacillus actinomycete- mcomitans [2]. The autoimmune basis of this disease was first postulated nearly fifty years ago by Brandtzaeg and Kraus [3]. The innate immune system has a general role against bacterial.

  8. Establishment of Intestinal Microbiota during Early Life: a Longitudinal, Explorative Study of a Large Cohort of Danish Infants

    DEFF Research Database (Denmark)

    Bergström, Anders; Skov, Thomas Hjort; Bahl, Martin Iain

    2014-01-01

    and introduction of a complementary feeding induce replacement of a microbiota characterized by lactobacilli, bifidobacteria, and Enterobacteriaceae with a microbiota dominated by Clostridium spp. and Bacteroides spp. Classification of samples by a proxy enterotype based on the relative levels of Bacteroides spp...

  9. NCBI nr-aa BLAST: CBRC-TTRU-01-0884 [SEVENS

    Lifescience Database Archive (English)

    Full Text Available CBRC-TTRU-01-0884 ref|ZP_03210142.1| hypothetical protein BACPLE_03833 [Bacteroides plebeiu...s DSM 17135] gb|EDY94379.1| hypothetical protein BACPLE_03833 [Bacteroides plebeius DSM 17135] ZP_03210142.1 0.12 22% ...

  10. NCBI nr-aa BLAST: CBRC-MLUC-01-0598 [SEVENS

    Lifescience Database Archive (English)

    Full Text Available CBRC-MLUC-01-0598 ref|ZP_03207828.1| hypothetical protein BACPLE_01456 [Bacteroides plebeiu...s DSM 17135] gb|EDY96150.1| hypothetical protein BACPLE_01456 [Bacteroides plebeius DSM 17135] ZP_03207828.1 5.5 28% ...

  11. Analysis of Gut Microbiota in Patients with Parkinson's Disease.

    Science.gov (United States)

    Petrov, V A; Saltykova, I V; Zhukova, I A; Alifirova, V M; Zhukova, N G; Dorofeeva, Yu B; Tyakht, A V; Kovarsky, B A; Alekseev, D G; Kostryukova, E S; Mironova, Yu S; Izhboldina, O P; Nikitina, M A; Perevozchikova, T V; Fait, E A; Babenko, V V; Vakhitova, M T; Govorun, V M; Sazonov, A E

    2017-04-01

    Gut microbiota of patients with Parkinson's disease and healthy volunteers was analyzed by the method of high throughput 16S rRNA sequencing of bacterial genomes. In patients with Parkinson's diseases, changes in the content of 9 genera and 15 species of microorganisms were revealed: reduced content of Dorea, Bacteroides, Prevotella, Faecalibacterium, Bacteroides massiliensis, Stoquefichus massiliensis, Bacteroides coprocola, Blautia glucerasea, Dorea longicatena, Bacteroides dorei, Bacteroides plebeus, Prevotella copri, Coprococcus eutactus, and Ruminococcus callidus, and increased content of Christensenella, Catabacter, Lactobacillus, Oscillospira, Bifidobacterium, Christensenella minuta, Catabacter hongkongensis, Lactobacillus mucosae, Ruminococcus bromii, and Papillibacter cinnamivorans. This microbiological pattern of gut microflora can trigger local inflammation followed by aggregation of α-synuclein and generation of Lewy bodies.

  12. Identifying abnormalities in symbiotic development between Trifolium spp. and Rhizobium leguminosarum bv. trifolii leading to sub-optimal and ineffective nodule phenotypes

    Science.gov (United States)

    Melino, V. J.; Drew, E. A.; Ballard, R. A.; Reeve, W. G.; Thomson, G.; White, R. G.; O'Hara, G. W.

    2012-01-01

    Background and Aims Legumes overcome nitrogen limitations by entering into a mutualistic symbiosis with N2-fixing bacteria (rhizobia). Fully compatible associations (effective) between Trifolium spp. and Rhizobium leguminosarum bv. trifolii result from successful recognition of symbiotic partners in the rhizosphere, root hair infection and the formation of nodules where N2-fixing bacteroids reside. Poorly compatible associations can result in root nodule formation with minimal (sub-optimal) or no (ineffective) N2-fixation. Despite the abundance and persistence of strains in agricultural soils which are poorly compatible with the commercially grown clover species, little is known of how and why they fail symbiotically. The aims of this research were to determine the morphological aberrations occurring in sub-optimal and ineffective clover nodules and to determine whether reduced bacteroid numbers or reduced N2-fixing activity is the main cause for the Sub-optimal phenotype. Methods Symbiotic effectiveness of four Trifolium hosts with each of four R. leguminosarum bv. trifolii strains was assessed by analysis of plant yields and nitrogen content; nodule yields, abundance, morphology and internal structure; and bacteroid cytology, quantity and activity. Key Results Effective nodules (Nodule Function 83–100 %) contained four developmental zones and N2-fixing bacteroids. In contrast, Sub-optimal nodules of the same age (Nodule Function 24–57 %) carried prematurely senescing bacteroids and a small bacteroid pool resulting in reduced shoot N. Ineffective-differentiated nodules carried bacteroids aborted at stage 2 or 3 in differentiation. In contrast, bacteroids were not observed in Ineffective-vegetative nodules despite the presence of bacteria within infection threads. Conclusions Three major responses to N2-fixation incompatibility between Trifolium spp. and R. l. trifolii strains were found: failed bacterial endocytosis from infection threads into plant cortical

  13. Senior Thai fecal microbiota comparison between vegetarians and non-vegetarians using PCR-DGGE and real-time PCR.

    Science.gov (United States)

    Ruengsomwong, Supatjaree; Korenori, Yuki; Sakamoto, Naoshige; Wannissorn, Bhusita; Nakayama, Jiro; Nitisinprasert, Sunee

    2014-08-01

    The fecal microbiotas were investigated in 13 healthy Thai subjects using polymerase chain reaction denaturing gradient gel electrophoresis (PCR-DGGE). Among the 186 DNA bands detected on the polyacrylamide gel, 37 bands were identified as representing 11 species: Bacteroides thetaiotaomicron, Bacteroides ovatus, Bacteroides uniformis, Bacteroides vulgatus, Clostridium colicanis, Eubacterium eligenes, E. rectale, Faecalibacterium prausnitzii, Megamonas funiformis, Prevotella copri, and Roseburia intestinalis, belonging mainly to the groups of Bacteroides, Prevotella, Clostridium, and F. prausnitzii. A dendrogram of the PCR-DGGE divided the subjects; vegetarians and non-vegetarians. The fecal microbiotas were also analyzed using a quantitative real-time PCR focused on Bacteroides, Bifidobacterium, Enterobacteriaceae, Clostrium coccoides-Eubacterium rectale, C. leptum, Lactobacillus, and Prevotella. The nonvegetarian and vegetarian subjects were found to have significant differences in the high abundance of the Bacteroides and Prevotella genera, respectively. No significant differences were found in the counts of Bifidabacterium, Enterobacteriaceae, C. coccoides-E. rectale group, C. leptum group, and Lactobacillus. Therefore, these findings on the microbiota of healthy Thais consuming different diets could provide helpful data for predicting the health of South East Asians with similar diets.

  14. Diet and the faecal microflora of infants, children and adults in rural Nigeria and urban U.K.

    OpenAIRE

    Tomkins, A. M.; Bradley, A. K.; Oswald, S.; Drasar, B. S.

    1981-01-01

    The faecal microflora of breast-fed infants, weaned children and adults has been examined in rural Nigeria and urban U.K. Breast-fed infants had a similar anaerobic flora dominated by bifidobacteria but bacteroides were isolated in less than a quarter of either community. Weaned children in both communities had greater numbers of bacteroides and clostridia than breast-fed infants. Even higher numbers of bacteroides and clostridia were present in U.K. adults but not in Nigerian adults. Numbers...

  15. Evaluation of Ellagic acid on the activities of oral bacteria with the ...

    African Journals Online (AJOL)

    Streptococcus mutans ATCC 25175, Streptococcus sanguis ATCC 10556, Streptococcus salivarius ATCC 25975, Actinomyces naeslundii ATCC 12104, Actinomyces viscosus ATCC 15987, Lactobacillus rhamnosus ATCC 53103, Porphyromonas gingivalis ATCC 33277 and Bacteroides forsythus ATCC 43037 were the ...

  16. Schematic Method for Effective Identification of Anaerobes from ...

    African Journals Online (AJOL)

    Further tests revealed Bacteroides fragilis, Fusobacterium nucleatium, Porphyromonas assacharolytica, Prevotella intermedia, and Peptosterptococcus magnus as most frequently isolated. The developed scheme interlinked the various identification steps: 1st level; inoculation and growth, 2nd level; Gram differentiation and ...

  17. Prevalence of gastrointestinal pathogenic bacteria in patients with ...

    African Journals Online (AJOL)

    Polymerase chain reaction (PCR) primers specific for Clostridium difficile, Shigella spp., Salmonella spp., Klebsiella oxytoca, enteropathogenic and enterohaemorrhagic Escherichia coli (EPEC/EHEC), Staphylococcus aureus, enterotoxigenic Bacteroides fragilis and Campylobacter spp. were used to screen total bacterial ...

  18. Aerobic Denitrification as an Innovative Method for In-Situ Biological Remediation of Contaminated Subsurface Sites

    Science.gov (United States)

    1989-01-01

    roseus Bacillus stearothermophilus Micrococcus varians Paracoccus denitrificans Bacillus coagulans Paracoccus halodenitrificans Bacillus flrmus Bacillus ...Geodermatophilus Plesiomonas Arachnia Haemophilus Propionibacterium Arthrobacter Halobacteriua Proteus Bacillus Ifalocuccus Pseudoraonas Bacteroides...Mycobacterium peregrinum Nocardia opaca Chromobacterium violaceum Bacillus subtllis Nocardia atlantica Bacillus licheniformis Flavobacterium

  19. Antibiotic susceptibility profiles of anaerobic pathogens in The Netherlands

    NARCIS (Netherlands)

    Veloo, A. C. M.; van Winkelhoff, A. J.

    The antibiotic susceptibility profile of the Bacteroides fragilis group, Gram-positive anaerobic cocci (GPAC), Fusobacterium spp., Prevotella spp., Veillonella spp. and Bilophila wadsworthia for amoxicillin, amoxicillin-clavulanic acid, clindamycin and metronidazole was determined. Human clinical

  20. Bacterial indicators of pollution of the Douala lagoon, Cameroon ...

    African Journals Online (AJOL)

    Eleven species of bacteria: Bacteroides fragilis, Proteus vulgaris, Klebsiella pneumoniae, E. coli, Enterococcus faecalis, Enterobacter aerogenes, Citrobacter freundii, Aeromonas hydrophila, Pseudomonas aeruginosa, Bacillus mycoides and Serratia marcesens, were frequently isolated. Conclusion: The presence of ...

  1. Research Summaries of 1988

    Science.gov (United States)

    1988-01-01

    STREPTOCOCCUS FAECALIS ON THE GROWTH OF BACTEROIDES SPECIES AND ANAEROBIC COCCI IV MIKED INFECTION. SURGERY 1988 JAN;103(1):107-10 INFECTIOUS...DISEASES N. A. BACTERIA, ANAEROBIC BACTERIAL INFECTIONS BACTEROIDS MICE STREPTOCOCCUS FAECALIS AD A203 932 NMRI 88-0080 BROOK I ENHANCEMEFT OF GROWTH OF...CO MACROPhAGE-CONDITIONED MEDIUM AND INTERLEUKIN 1 SUPPRESS VASCULAR CONTRACTILITY. CIRCULATORY SHOCK 1988 JULY; 25(3):187-96 CASUALTY CARE

  2. The symbiosis between Rhizobium leguminosarum and Pisum sativum : regulation of the nitrogenase activity

    OpenAIRE

    Appels, M.A.

    1989-01-01

    Bacteria of the genus Rhizobium can form a symbiosis with plants of the family Leguminosae. Both bacteria and plant show considerable biochemical and morphological changes in order to develop and carry out the symbiosis. The Rhizobia induce special structures on the legumes, which are called root nodules. In these root nodules, the differentiated bacteria - so-called bacteroids - are localized. Within the root nodule the bacteroid...

  3. A General O-Glycosylation System Important to the Physiology of a Major Human Intestinal Symbiont

    OpenAIRE

    Fletcher, C. Mark; Coyne, Michael J.; Villa, Otto F.; Chatzidaki-Livanis, Maria; Comstock, Laurie E.

    2009-01-01

    The Bacteroides are a numerically dominant genus of the human intestinal microbiota. These organisms harbor a rare bacterial pathway for incorporation of exogenous fucose into capsular polysaccharides and glycoproteins. The infrequency of glycoprotein synthesis by bacteria prompted a more detailed analysis of this process. Here, we demonstrate that Bacteroides fragilis has a general O-glycosylation system. The proteins targeted for glycosylation include those predicted to be involved in prote...

  4. Exposure to human-associated fecal indicators and self-reported illness among swimmers at recreational beaches: a cohort study.

    Science.gov (United States)

    Napier, Melanie D; Haugland, Richard; Poole, Charles; Dufour, Alfred P; Stewart, Jill R; Weber, David J; Varma, Manju; Lavender, Jennifer S; Wade, Timothy J

    2017-10-02

    Fecal indicator bacteria used to assess illness risks in recreational waters (e.g., Escherichia coli, Enterococci) cannot discriminate among pollution sources. To address this limitation, human-associated Bacteroides markers have been proposed, but the risk of illness associated with the presence of these markers in recreational waters is unclear. Our objective was to estimate associations between human-associated Bacteroides markers in water and self-reported illness among swimmers at 6 U.S. beaches spanning 2003-2007. We used data from a prospectively-enrolled cohort of 12,060 swimmers surveyed about beach activities and water exposure on the day of their beach visit. Ten to twelve days later, participants reported gastroinestinal, diarrheal, and respiratory illnesses experienced since the visit. Daily water samples were analyzed for the presence of human-associated Bacteroides genetic markers: HF183, BsteriF1, BuniF2, HumM2. We used model-based standardization to estimate risk differences (RD) and 95% confidence intervals (CI). We assessed whether the presence of Bacteroides markers were modifiers of the association between general Enterococcus and illness among swimmers using interaction contrast. Overall we observed inconsistent associations between the presence of Bacteroides markers and illness. There was a pattern of increased risks of gastrointestinal (RD = 1.9%; 95% CI: 0.1%, 3.7%), diarrheal (RD = 1.3%; 95% CI: -0.2%, 2.7%), and respiratory illnesses (RD = 1.1%; 95% CI: -0.2%, 2.5%) associated with BsteriF1. There was no evidence that Bacteroides markers acted as modifiers of Enterococcus and illness. Patterns were similar when stratified by water matrix. Quantitative measures of fecal pollution using Bacteroides, rather than presence-absence indicators, may be necessary to accurately assess human risk specific to the presence of human fecal pollution.

  5. Nitrogen assimilation in soybean nodules, 2

    International Nuclear Information System (INIS)

    Ohyama, Takuji; Kumazawa, Kikuo

    1980-01-01

    15 N assimilation was studied in bacteroid and cytosol fractions of soybean nodules. In the first experiment, after exposing the intact nodules to 15 N 2 for 5 min and 10 min, most of the fixed 15 N was detected in cytosol fraction. In cytosol fraction, 15 N content of glutamine was the highest and followed by glutamic acid, alanine, and allantoin in this sequence, whereas, in bacteroid fraction, glutamic acid showed the highest 15 N content and alanine and glutamine followed. In the second experiment, 15 N assimilation of various 15 N-labeled compounds in the separated bacteroid and cytosol fractions was investigated. In the separated bacteroid fraction which was fed with 15 NH 4 , 15 N was incorporated very rapidly into glutamic acid, alanine, and aspartic acid, but very slowly into glutamine. From these results, it was suggested that most of the fixed ammonia was exported to cytosol and assimilated via glutamine synthetase to glutamine, then via glutamate synthase to glutamic acid, and from these compounds various nitrogenous compounds were formed, but in bacteroids glutamate dehydrogenase and alanine dehydrogenase played an important role in the assimilation of fixed ammonia though quantitatively the contribution to ammonia assimilation in nodules was much less compared with cytosol. (author)

  6. Increase of faecal tryptic activity relates to changes in the intestinal microbiome: analysis of Crohn's disease with a multidisciplinary platform.

    Directory of Open Access Journals (Sweden)

    Tore Midtvedt

    Full Text Available OBJECTIVE: To investigate-by molecular, classical and functional methods-the microbiota in biopsies and faeces from patients with active Crohn's disease (CD and controls. DESIGN: The microbiota in biopsies was investigated utilizing a novel molecular method and classical cultivation technology. Faecal samples were investigated by classical technology and four functional methods, reflecting alterations in short chain fatty acids pattern, conversion of cholesterol and bilirubin and inactivation of trypsin. RESULTS: By molecular methods we found more than 92% similarity in the microbiota on the biopsies from the two groups. However, 4.6% of microbes found in controls were lacking in CD patients. Furthermore, NotI representation libraries demonstrate two different clusters representing CD patients and controls, respectively. Utilizing conventional technology, Bacteroides (alt. Parabacteroides was less frequently detected in the biopsies from CD patients than from controls. A similar reduction in the number of Bacteroides was found in faecal samples. Bacteroides is the only group of bacteria known to be able to inactivate pancreatic trypsin. Faecal tryptic activity was high in CD patients, and inversely correlated to the levels of Bacteroides. CONCLUSIONS: CD patients have compositional and functional alterations in their intestinal microbiota, in line with the global description hypothesis rather than the candidate microorganism theory. The most striking functional difference was high amount of faecal tryptic activity in CD patients, inversely correlated to the levels of Bacteroides in faeces.

  7. Presence of microbial and chemical source tracking markers in roof-harvested rainwater and catchment systems for the detection of fecal contamination.

    Science.gov (United States)

    Waso, M; Ndlovu, T; Dobrowsky, P H; Khan, S; Khan, W

    2016-09-01

    Microbial source tracking (MST) and chemical source tracking (CST) markers were utilized to identify fecal contamination in harvested rainwater and gutter debris samples. Throughout the sampling period, Bacteroides HF183 was detected in 57.5 % of the tank water samples and 95 % of the gutter debris samples, while adenovirus was detected in 42.5 and 52.5 % of the tank water and gutter debris samples, respectively. Human adenovirus was then detected at levels ranging from below the detection limit to 316 and 1253 genome copies/μL in the tank water and debris samples, respectively. Results for the CST markers showed that salicylic acid (average 4.62 μg/L) was the most prevalent marker (100 %) in the gutter debris samples, caffeine (average 18.0 μg/L) was the most prevalent in the tank water samples (100 %) and acetaminophen was detected sporadically throughout the study period. Bacteroides HF183 and salicylic acid (95 %) and Bacteroides HF183 and caffeine (80 %) yielded high concurrence frequencies in the gutter debris samples. In addition, the highest concurrence frequency in the tank water samples was observed for Bacteroides HF183 and caffeine (60 %). The current study thus indicates that Bacteroides HF183, salicylic acid and caffeine may potentially be applied as source tracking markers in rainwater catchment systems in order to supplement fecal indicator analyses.

  8. Identifikasi Bakteri Pada Serasah Daun Mangrove yang Terdekomposisi di Kawasan Konservasi Mangrove dan Bekantan (KKMB Kota Tarakan

    Directory of Open Access Journals (Sweden)

    Y. Yulma

    2017-10-01

    Full Text Available Bacteria in mangrove ecosystem has a significant role in litter decomposition that is essential to provide organic nutrition for organisms in mangrove forest. The research was aimed to identify decomposition bacteria that exist in KKMB Tarakan mangrove conservation area. The identification focused on litters from several mangrove vegetation, which are Bruguiera parviflora, Rhizophora apiculata, Sonneratia alba, dan Avicennia alba. The method used was explorative descriptive while testing parameter was genus. The research identified seven bacteria genera for litter from Bruguiera parviflora which are Bacillus, Aeromonas, Nocardiae, Corynebacterium, Listeria, Bacteroides, Pseudomonas. Six genera from Rhizophora apiculata which are Bacillus, Listeria, Enterobacteria, Aeromonas, Actinobacilus, and Bacteroides. Five genera for Sonneratia alba which are Bacillus, Aeromonas, Listeria, Enterobacteria, Staphylococcus. Also eight genera from Avicennia alba which are Bacillus, Clostridium, Enterobacteria, Bacteroides, Plesiomonas, Bordella, Streptococcus, and Neisseria. The results conclude that different species of mangrove vegetation attracts different species of bacteria as well.

  9. Production of α-galactosylceramide by a prominent member of the human gut microbiota.

    Directory of Open Access Journals (Sweden)

    Laura C Wieland Brown

    2013-07-01

    Full Text Available While the human gut microbiota are suspected to produce diffusible small molecules that modulate host signaling pathways, few of these molecules have been identified. Species of Bacteroides and their relatives, which often comprise >50% of the gut community, are unusual among bacteria in that their membrane is rich in sphingolipids, a class of signaling molecules that play a key role in inducing apoptosis and modulating the host immune response. Although known for more than three decades, the full repertoire of Bacteroides sphingolipids has not been defined. Here, we use a combination of genetics and chemistry to identify the sphingolipids produced by Bacteroides fragilis NCTC 9343. We constructed a deletion mutant of BF2461, a putative serine palmitoyltransferase whose yeast homolog catalyzes the committed step in sphingolipid biosynthesis. We show that the Δ2461 mutant is sphingolipid deficient, enabling us to purify and solve the structures of three alkaline-stable lipids present in the wild-type strain but absent from the mutant. The first compound was the known sphingolipid ceramide phosphorylethanolamine, and the second was its corresponding dihydroceramide base. Unexpectedly, the third compound was the glycosphingolipid α-galactosylceramide (α-GalCer(Bf, which is structurally related to a sponge-derived sphingolipid (α-GalCer, KRN7000 that is the prototypical agonist of CD1d-restricted natural killer T (iNKT cells. We demonstrate that α-GalCer(Bf has similar immunological properties to KRN7000: it binds to CD1d and activates both mouse and human iNKT cells both in vitro and in vivo. Thus, our study reveals BF2461 as the first known member of the Bacteroides sphingolipid pathway, and it indicates that the committed steps of the Bacteroides and eukaryotic sphingolipid pathways are identical. Moreover, our data suggest that some Bacteroides sphingolipids might influence host immune homeostasis.

  10. NCBI nr-aa BLAST: CBRC-TTRU-01-0654 [SEVENS

    Lifescience Database Archive (English)

    Full Text Available CBRC-TTRU-01-0654 ref|ZP_05544813.1| multidrug efflux pump BexA [Parabacteroides sp.... D13] ref|ZP_06077587.1| multidrug efflux pump BexA [Bacteroides sp. 2_1_33B] gb|EEU51559.1| multidrug efflux pump... BexA [Parabacteroides sp. D13] gb|EEY81680.1| multidrug efflux pump BexA [Bacteroides sp. 2_1_33B] ZP_05544813.1 0.034 23% ...

  11. Nitrogen transfer in the interface between the symbionts in pea root nodules

    DEFF Research Database (Denmark)

    Rosendahl, L.; Mouritzen, P.; Rudbeck, A.

    2001-01-01

    Transport mechanisms for transfer of nitrogen from the bacteroid side across the symbiosome membrane of pea (Pisum sativum L.) root nodules were identified by the use of energised bacteroid side-out symbiosome membrane vesicles. Such membrane vesicles were used to study a mechanism with high...... was not observed. The ammonium transporter has been identified as a voltage-driven channel whereas the symbiosome membrane aspartate transporter appears to be a H+/aspartate symport. The results suggest that nitrogen transfer between the symbionts in pea root nodules involves transfer of amino acids as well...

  12. Studies in the Nature and Control of Sepsis in Thermal and Combined Thermal-Irradiation Injuries

    Science.gov (United States)

    1970-03-01

    0.3 Actinomyces israelii 1 0.3 Actinornyces sp. 2 0.7 Bacteroides melaninogenicus 70 22.8 species 80 64 20.8 Catenabacterium sp. 1 0.3 Clostridium ...tertium 1 0.3 tetani 1 0.3 species 6 2.0 Corynebacterium sp. 23 22 7.2 Dialister sp. 1 0.3 Fusobacterium sp. 12 3.9 Peptccoccus sp. 38 33 10.7...dence dence Bacteroides: melaninogenicus 2 7.1 species 3 10.7 Clostridium : difficile 1 3.6 perfringens 2 7.1 Corynebacterium sp. 5 17.9 Peptococcus sp. 1

  13. Effects of microgravity on the binding of acetylsalicylic acid by Rhizobium leguminosarum bv. trifolii

    Science.gov (United States)

    Urban, James E.; Gerren, Richard; Zoelle, Jeffery

    1995-07-01

    Bacteroids can be induced in vitro by treating growing Rhizobium leguminosarum bv. trifolii with succinic acid or succinic acid structural analogs like acetylsalicylic acid. Quantitating bacteroid induction by measuring acetylsalicylic binding under normal (1 g) conditions showed two forms of binding to occur. In one form of binding cells immediately bound comparatively high levels of acetylsalicylic acid, but the binding was quickly reversed. The second form of binding increased with time by first-order kinetics, and reached saturation in 40 s. Similar experiments performed in the microgravity environment aboard the NASA 930 aircraft showed only one form of binding and total acetylsalicylic acid bound was 32% higher than at 1 g.

  14. Browse Title Index

    African Journals Online (AJOL)

    Items 2951 - 3000 of 11090 ... Vol 8, No 10 (2009), Detection of Bacteroides forsythus and Porphyromonas gingivalis in infected root canals during periapical periodontitis by 16S rDNA, Abstract PDF. TYW Loo, LJ Jin, MNB Cheung, Y Dou. Vol 11, No 17 (2012), Detection of Dientamoeba fragilis in patients referred to Chaloos ...

  15. Emerging synbiotics and their effect on the composition and functionality of the human gut microbiota

    DEFF Research Database (Denmark)

    van Zanten, Gabriella Christina

    using qPCR results for Bacteroides-Prevotella-Porphyromonas group, Clostridium perfringens cluster I, Clostridium coccoides - Eubacterium rectale group and Clostridial cluster XIV for the colonic All the emerging synbiotics investigated in the colonic model system were able to increase levels of SCFA...

  16. Comparative in vitro activity of piperacillinl tazobactam against ...

    African Journals Online (AJOL)

    All the agents, with the exception of ampicillin (MIC90 4 mg/l) and chloramphenicol (MIC90 4 mg/l), were highly active against the Haemophilus influenzae isolates tested. All Bacteroides fragilis strains were susceptible to piperacillinllazobaclam (MIC90 8/4 mgll), as well as 10 co-amoxiclav (MIC90 4/2 mg/I), biapenem and ...

  17. Dietary Fiber-Induced Improvement in Glucose Metabolism Is Associated with Increased Abundance of Prevotella

    DEFF Research Database (Denmark)

    Kovatcheva-Datchary, Petia; Nilsson, Anne; Akrami, Rozita

    2015-01-01

    consumption of barley kernel-based bread (BKB) with those who responded least to this dietary intervention. The Prevotella/Bacteroides ratio was higher in responders than non-responders after BKB. Metagenomic analysis showed that the gut microbiota of responders was enriched in Prevotella copri and had...

  18. Lactobacillus GG prevents recurrence of colitis in HLA-B27 transgenic rats after antibiotic treatment

    NARCIS (Netherlands)

    Dieleman, L. A.; Goerres, M. S.; Arends, A.; Sprengers, D.; Torrice, C.; Hoentjen, F.; Grenther, W. B.; Sartor, R. B.

    2003-01-01

    Bacteroides vulgatus induces colitis in gnotobiotic HLA-B27 transgenic (TG) rats while broad spectrum antibiotics prevent and treat colitis in specific pathogen free (SPF) TG rats although disease recurs after treatment ends. Lactobacilli treat human pouchitis and experimental colitis. We

  19. Fecal microbiota composition and frailty

    NARCIS (Netherlands)

    van Tongeren, SP; Slaets, JPJ; Harmsen, HJM; Welling, GW

    2005-01-01

    The relationship between fecal microbiota composition and frailty in the elderly was studied. Fecal samples from volunteers with high frailty scores showed a significant reduction in the number of lactobacilli (26-fold). At much higher population levels, both the Bacteroides/Prevotella (threefold)

  20. Monitoring bacterial faecal contamination in waters using multiplex ...

    African Journals Online (AJOL)

    Monitoring of sanitary quality or faecal pollution in water is currently based on quantifying some bacterial indicators such as Escherichia coli and faecal enterococci. Using a multiplex real-time PCR assay for faecal enterococci and Bacteroides spp., the detection of faecal contamination in non-treated water can be done in a ...

  1. Regulation of innate and adaptive immunity by the commensal microbiota

    OpenAIRE

    Jarchum, Irene; Pamer, Eric G.

    2011-01-01

    The microbial communities that inhabit the intestinal tract are essential for mammalian health. Communication between the microbiota and the host establishes and maintains immune homeostasis, enabling protective immune responses against pathogens while preventing adverse inflammatory responses to harmless commensal microbes. Specific bacteria, such as segmented filamentous bacteria, Clostridium species, and Bacteroides fragilis, are key contributors to immune homeostasis in the gut. The cellu...

  2. Synergic activity, for anaerobes, of trovafloxacin with clindamycin or metronidazole: chequerboard and time-kill methods.

    Science.gov (United States)

    Ednie, L M; Credito, K L; Khantipong, M; Jacobs, M R; Appelbaum, P C

    2000-05-01

    Chequerboard titrations were used to test the activity of trovafloxacin, alone and in combination with clindamycin or metronidazole, against 156 Gram-positive or Gram-negative anaerobes, including 47 Bacteroides fragilis group, 36 Prevotella spp., 26 fusobacteria, 21 peptostreptococci and 26 clostridia. MIC50/MIC90 values (mg/L) of each drug alone against all 156 strains were: trovafloxacin, 0.5/1; clindamycin, 0.25/2; metronidazole, 1/2. Synergy (FIC indices 0. 5-2.0); no antagonism (FIC indices >4.0) was seen. In addition, synergy was tested by time-kill methodology for each of the above combinations against 12 Gram-positive or Gram-negative strains. Results indicated that synergy (defined as a >/= 2 log(10) decrease in cfu/mL at 48 h compared with the more active drug alone) was found between trovafloxacin at or below the MIC and both clindamycin and metronidazole at or below the MIC in one strain each of Bacteroides fragilis, Bacteroides thetaiotaomicron, Prevotella intermedia, Fusobacterium varium, Peptostreptococcus asaccharolyticus and Clostridium bifermentans. Synergy between trovafloxacin (Bacteroides distasonis, Prevotella bivia, Fusobacterium mortiferum, P. asaccharolyticus and C. bifermentans. In many cases of synergy, including those at the trovafloxacin MIC, regrowth after 48 h, which was commonly seen with trovafloxacin alone, was inhibited, and 99.9% killing was observed with the combination after 48 h, but not with trovafloxacin alone.

  3. Antimicrobial resistance determinants among anaerobic bacteria isolated from footrot.

    Science.gov (United States)

    Lorenzo, María; García, Nuria; Ayala, Juan Alfonso; Vadillo, Santiago; Píriz, Segundo; Quesada, Alberto

    2012-05-25

    Antibiotic resistance has been evaluated among 36 Gram negative and anaerobic bacilli (10 Bacteroides, 11 Prevotella, 7 Porphyromonas and 8 Fusobacterium strains) isolated from clinical cases of caprine and ovine footrot (necrotic pododermatitis). The initial analysis on this bacterial consortium evaluates the relationships existing among antimicrobial resistance determinants, phenotype expression and mobilization potential. The Bacteroides strains were generally resistant to penicillins, first-generation cephalosporins, tetracycline and erythromycin, and expressed low level of β-lactamase activity. The main determinants found among the Bacteroides strains were cepA and tetQ genes, conferring resistance to β-lactams and tetracycline, respectively. A general susceptibility to β-lactams was shown for most Prevotella, Porphyromonas and Fusobacterium strains, where none of the β-lactamase genes described in Bacteroides was detected. Resistance to tetracycline and/or erythromycin was found among the three bacterial groups. Although tetQ genes were detected for several Prevotella and Porphyromonas strains, a unique ermF positive was revealed among Prevotella strains. The expression of resistance markers was not related with the polymorphism of their coding sequences. However, the finding of sequence signatures for conjugative transposons in the vicinities of tetQ and ermF suggests a mobilization potential that might have contributed to the spread of antimicrobial resistance genes. Copyright © 2011 Elsevier B.V. All rights reserved.

  4. the place of quinolones in the treatment of enteric fevers in the 21st ...

    African Journals Online (AJOL)

    Dr. Jombo

    Among the antimicrobials presently available for the treatment of enteric fever, preferences for quinolones ... resistant to all the antimicrobial agents tested except norfloxacin (Kamili, et al,. 1993). Also in Moscow .... Clostridium perfringens, Bacteroides fragilis and Branhamella. Also in New Zealand, lomefloxacin, besides.

  5. Cavernosal Abscess due to Streptococcus Anginosus: A Case Report and Comprehensive Review of the Literature.

    Science.gov (United States)

    Dugdale, Caitlin M; Tompkins, Andrew J; Reece, Rebecca M; Gardner, Adrian F

    2013-08-01

    Corpus cavernosum abscesses are uncommon with only 23 prior reports in the literature. Several precipitating factors for cavernosal infections have been described including injection therapy for erectile dysfunction, trauma, and priapism. Common causal organisms include Staphylococcus aureus, Streptococci, and Bacteroides. We report a unique case of a corpus cavernosum abscess due to proctitis with hematological seeding and review the literature on cavernosal abscesses.

  6. Bacterial RuBisCO is required for efficient Bradyrhizobium/Aeschynomene symbiosis.

    Directory of Open Access Journals (Sweden)

    Benjamin Gourion

    Full Text Available Rhizobia and legume plants establish symbiotic associations resulting in the formation of organs specialized in nitrogen fixation. In such organs, termed nodules, bacteria differentiate into bacteroids which convert atmospheric nitrogen and supply the plant with organic nitrogen. As a counterpart, bacteroids receive carbon substrates from the plant. This rather simple model of metabolite exchange underlies symbiosis but does not describe the complexity of bacteroids' central metabolism. A previous study using the tropical symbiotic model Aeschynomene indica/photosynthetic Bradyrhizobium sp. ORS278 suggested a role of the bacterial Calvin cycle during the symbiotic process. Herein we investigated the role of two RuBisCO gene clusters of Bradyrhizobium sp. ORS278 during symbiosis. Using gene reporter fusion strains, we showed that cbbL1 but not the paralogous cbbL2 is expressed during symbiosis. Congruently, CbbL1 was detected in bacteroids by proteome analysis. The importance of CbbL1 for symbiotic nitrogen fixation was proven by a reverse genetic approach. Interestingly, despite its symbiotic nitrogen fixation defect, the cbbL1 mutant was not affected in nitrogen fixation activity under free living state. This study demonstrates a critical role for bacterial RuBisCO during a rhizobia/legume symbiotic interaction.

  7. Human fecal source identification with real-time quantitative PCR

    Science.gov (United States)

    Waterborne diseases represent a significant public health risk worldwide, and can originate from contact with water contaminated with human fecal material. We describe a real-time quantitative PCR (qPCR) method that targets a Bacteroides dori human-associated genetic marker for...

  8. Identification of a transport mechanism for NH4+ in the symbiosome membrane of pea root nodules

    DEFF Research Database (Denmark)

    Mouritzen, P.; Rosendahl, L.

    1997-01-01

    Symbiosome membrane vesicles, facing bacteroid-side-out, were purified from pea (Pisum sativum L.) root nodules and used to study NH4+ transport across the membrane by recording vesicle uptake of the NH4+ analog [C-14]methylamine (MA). Membrane potentials (Delta psi) were imposed on the vesicles ...

  9. Epidemiology and Antimicrobial Susceptibilities of Wound Isolates of Obligate Anaerobes from Combat Casualties

    Science.gov (United States)

    White, Brian K.; Mende, Katrin; Weintrob, Amy C.; Beckius, Miriam L.; Zera, Wendy C.; Lu, Dan; Bradley, William; Tribble, David R.; Schnaubelt, Elizabeth R.; Murray, Clinton K.

    2015-01-01

    Data from recent conflicts related to war wounds and obligate anaerobes are limited. We define the epidemiology and antimicrobial susceptibility of obligate anaerobes from Iraq and Afghanistan casualties (6/2009–12/2013), as well as their association with clinical outcomes. Susceptibility against eleven antibiotics (7 classes) was tested. Overall, 59 patients had 119 obligate anaerobes identified (83 were first isolates). Obligate anaerobes were isolated 7–13 days post-injury, primarily from lower extremity wounds (43%), and were largely Bacteroides spp. (42%) and Clostridium spp. (19%). Patients with pelvic wounds were more likely to have Bacteroides spp. and concomitant resistant gram-negative aerobes. Seventy-three percent of isolates were resistant to ≥1 antimicrobials. Bacteroides spp. demonstrated the most resistance (16% of first isolates). Patients with resistant isolates had similar outcomes to those with susceptible strains. Serial recovery of isolates occurred in 15% of patients and was significantly associated with isolation of Bacteroides spp., along with resistant gram-negative aerobes. PMID:26607420

  10. Metabolite profiles of nodulated alfalfa plants indicate that distinct stages of nodule organogenesis are accompanied by global physiological adaptations.

    Science.gov (United States)

    Barsch, Aiko; Tellström, Verena; Patschkowski, Thomas; Küster, Helge; Niehaus, Karsten

    2006-09-01

    An effective symbiosis between Sinorhizobium meliloti and its host plant Medicago sativa is dependent on a balanced physiological interaction enabling the microsymbiont to fix atmospheric nitrogen. Maintenance of the symbiotic interaction is regulated by still poorly understood control mechanisms. A first step toward a better understanding of nodule metabolism was the determination of characteristic metabolites for alfalfa root nodules. Furthermore, nodules arrested at different developmental stages were analyzed in order to address metabolic changes induced during the progression of nodule formation. Metabolite profiles of bacteroid-free pseudonodule extracts indicated that early nodule developmental processes are accompanied by photosynthate translocation but no massive organic acid formation. To determine metabolic adaptations induced by the presence of nonfixing bacteroids, nodules induced by mutant S. meliloti strains lacking the nitrogenase protein were analyzed. The bacteroids are unable to provide ammonium to the host plant, which is metabolically reflected by reduced levels of characteristic amino acids involved in ammonium fixation. Elevated levels of starch and sugars in Fix(-) nodules provide strong evidence that plant sanctions preventing a transformation from a symbiotic to a potentially parasitic interaction are not strictly realized via photosynthate supply. Instead, metabolic and gene expression data indicate that alfalfa plants react to nitrogen-fixation-deficient bacteroids with a decreased organic acid synthesis and an early induction of senescence. Noneffective symbiotic interactions resulting from plants nodulated by mutant rhizobia also are reflected in characteristic metabolic changes in leaves. These are typical for nitrogen deficiency, but also highlight metabolites potentially involved in sensing the N status.

  11. Laminitis and interdigital dermatitis and heel horn erosion. A European perspective.

    Science.gov (United States)

    Peterse, D J

    1985-03-01

    Laminitis is one of the most important claw disorders in dairy herds. Nutrition, calving, burdening of the lateral claw of the rear feet, and hereditary susceptibility are all contributing factors. Interdigital dermatitis in cattle may be a result of infection by Bacteroides nodosus and Fusobacterium necrophorum. If this infection becomes chronic, heel horn erosion is its consequence.

  12. [Characteristics of peritoneal exudate microflora in children with appendicular peritonitis].

    Science.gov (United States)

    Bodnar, B M

    1997-01-01

    Bacteriological investigation of peritoneal exudate was conducted in 131 children with peritonitis. The greatest quantity of pathogenic and conventionally pathogenic Escherichias and bacteroids was revealed in March, April and September. In summer peritonitis was caused by pathogenic and conventionally pathogenic Escherichias in association with enterobacterias, staphylococci and other microorganisms.

  13. Exploring symbiotic nitrogen fixation and assimilation in pea root nodules by in vivo 15N nuclear magnetic resonance spectroscopy and liquid chromatography-mass spectrometry

    DEFF Research Database (Denmark)

    Scharff, A.M.; Egsgaard, H.; Hansen, P.E.

    2003-01-01

    indicate that ammonium is located in the bacteroids. The observed N-15-labeled amino acids, glutamine/glutamate and asparagine (Asn), apparently reside in a different compartment, presumably the plant cytoplasm, because no changes in the expected in vivo N-15 chemical shifts were observed. Extensive N-15...

  14. Quantification of bacteria adherent to gastrointestinal mucosa by real-time PCR

    NARCIS (Netherlands)

    Huijsdens, Xander W.; Linskens, Ronald K.; Mak, Mariëtte; Meuwissen, Stephan G. M.; Vandenbroucke-Grauls, Christina M. J. E.; Savelkoul, Paul H. M.

    2002-01-01

    The use of real-time quantitative PCR (5' nuclease PCR assay) as a tool to study the gastrointestinal microflora that adheres to the colonic mucosa was evaluated. We developed primers and probes based on the 16S ribosomal DNA gene sequences for the detection of Escherichia coli and Bacteroides

  15. Gut microbiota in 2015: Prevotella in the gut: choose carefully.

    Science.gov (United States)

    Ley, Ruth E

    2016-02-01

    Gut microbial communities often contain many Bacteroides or their close relatives, Prevotella, but not both. Prevotella strains are associated with plant-rich diets but are also linked with chronic inflammatory conditions. In 2015, papers probed the genomic diversity of Prevotella strains and interactions of Prevotella copri with its host and other bacteria.

  16. Assessment of Equine Fecal Contamination: The Search for Alternative Bacterial Source-tracking Targets

    Science.gov (United States)

    16S rDNA clone libraries were evaluated for detection of fecal source-identifying bacteria from a collapsed equine manure pile. Libraries were constructed using universal eubacterial primers and Bacteroides-Prevotella group-specific primers. Eubacterial sequences indicat...

  17. Prebiotic effects of Vernonia amygdalina and Ocimum gratissimum ...

    African Journals Online (AJOL)

    Species of Corynebacterium, Enterococcus, Bacteroides, Lactobacillus and Actinomyces were identified as resident bacteria in the rabbit gastrointestinal tract (GIT). Consumption of Vernonia amygdalina extract selectively and significantly (p < 0.05) increased the numbers of Enterococcus and Actinomyces species ...

  18. [Comparative study of the antimicrobial effect of various cavity liners used in conservative dentistry].

    Science.gov (United States)

    Pumarola Suñé, J; Espias Gómez, A; Canalda Sahli, C

    1989-01-01

    We have compared the microbiological activity of the following cavity liners: Life, Dycal II, Calcipulpe, Pure calcium hydroxide and Cavitec; against five different bacterial strains: Veillonella parvula, Bacteroides fragilis, Peptococcus s.p., Staphylococcus aureus, and Streptococcus beta hemolytic: The results demonstrate the higher antimicrobial activity of the manufactured cavity liners with calcium hydroxide base in comparison with the pure calcium hydroxide.

  19. Influence of age and immunization on development of gingivitis in rats

    DEFF Research Database (Denmark)

    Lekic, P; Klausen, B; Friis-Hasché, E

    1989-01-01

    To study the effect of age and antigenic priming on the development of gingivitis, 33 healthy rats were placed in contact with Streptococcus mutans, Actinomyces viscosus, Fusobacterium nucleatum, and Bacteroides gingivalis. On days 0, 3, 7, and 14 after inoculation, the gingival condition...

  20. Dicty_cDB: [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available |pid:none) Cupriavidus taiwanensis str. LM... 34 4.1 AE015928_2526( AE015928 |pid:none) Bacteroides thetaiot...168 |pid:none) Ralstonia solanacearum strain I... 35 3.1 CU633749_1834( CU633749

  1. The lipopolysaccharide lipid-a long chain fatty acid is important for rhizobium leguminosarum growth and stress adaptation in free-living and nodule environments

    Science.gov (United States)

    Rhizobium bacteria live in soil and plant environments, are capable of inducing symbiotic nodules on legumes, invade these nodules, and develop into bacteroids that fix atmospheric nitrogen into ammonium. Lipopolysaccharide (LPS) is anchored in the bacterial outer membrane through a specialized lipi...

  2. Disease: H01410 [KEGG MEDICUS

    Lifescience Database Archive (English)

    Full Text Available us disease caused by Bacteroides spp., Prevotella spp., Porphyromonas spp., Porphyromonas spp., Fusobacterium spp., Peptostreptococcu...e cocci (primarily Peptostreptococcus) and sporeforming (Clostridium) and non-spo...roides, Prevotella, Porphyromonas, Fusobacterium and Bilophila). Among the Gram-positive anaerobes, there ar

  3. Isolaltooligosaccharide synthetized from rice starch and its prebiotic properties in vitro

    DEFF Research Database (Denmark)

    Plongbunjong, Vijitra; Graidist, Potchanapond; Knudsen, Knud Erik Bach

    2017-01-01

    a dietary fibre content of 1.1%. In vitro (consisted of three vessels) fermentation of instant Sang-Yod rice porridge (ISYRP) mixed with IMO showed a slight increase in beneficial bacteria, bifidobacteria and lactobacilli. On the other hand, the pathogenic bacteria, clostridia and bacteroides were decreased...

  4. PCR-based detection of resistance genes in anaerobic bacteria isolated from intra-abdominal infections.

    Science.gov (United States)

    Tran, Chau Minh; Tanaka, Kaori; Watanabe, Kunitomo

    2013-04-01

    Little information is available on the distribution of antimicrobial resistance genes in anaerobes in Japan. To understand the background of antimicrobial resistance in anaerobes involved in intra-abdominal infections, we investigated the distribution of eight antimicrobial resistance genes (cepA, cfiA, cfxA, ermF, ermB, mefA, tetQ, and nim) and a mutation in the gyrA gene in a total of 152 organisms (Bacteroides spp., Prevotella spp., Fusobacterium spp., Porphyromonas spp., Bilophila wadsworthia, Desulfovibrio desulfuricans, Veillonella spp., gram-positive cocci, and non-spore-forming gram-positive bacilli) isolated between 2003 and 2004 in Japan. The cepA gene was distributed primarily in Bacteroides fragilis. Gene cfxA was detected in about 9 % of the Bacteroides isolates and 75 % of the Prevotella spp. isolates and did not appear to contribute to cephamycin resistance. Two strains of B. fragilis contained the metallo-β-lactamase gene cfiA, but they did not produce the protein product. Gene tetQ was detected in about 81, 44, and 63 % of B. fragilis isolates, other Bacteroides spp., and Prevotella spp. isolates, respectively. The ermF gene was detected in 25, 13, 56, 64, and 16 % of Bacteroides spp., Prevotella spp., Fusobacterium spp., B. wadsworthia, and anaerobic cocci, respectively. Gene mefA was found in only 10 % of the B. fragilis strains and 3 % of the non-B. fragilis strains. Genes nim and ermB were not detected in any isolate. Substitution at position 82 (Ser to Phe) in gyrA was detected in B. fragilis isolates that were less susceptible or resistant to moxifloxacin. This study is the first report on the distribution of resistance genes in anaerobes isolated from intra-abdominal infections in Japan. We expect that the results might help in understanding the resistance mechanisms of specific anaerobes.

  5. Comparison of the gut microbiota composition between obese and non-obese individuals in a Japanese population, as analyzed by terminal restriction fragment length polymorphism and next-generation sequencing.

    Science.gov (United States)

    Kasai, Chika; Sugimoto, Kazushi; Moritani, Isao; Tanaka, Junichiro; Oya, Yumi; Inoue, Hidekazu; Tameda, Masahiko; Shiraki, Katsuya; Ito, Masaaki; Takei, Yoshiyuki; Takase, Kojiro

    2015-08-11

    Obesity has become one of the most serious social problems in developed countries, including Japan. The relationship between the gut microbiota and obesity has recently attracted the attention of many researchers. Although the gut microbiota was long thought to contribute to obesity, the exact association remains largely unknown. We examined the human gut microbiota composition in a Japanese population in order to determine its relationship to obesity. Stool samples from 23 non-obese subjects (body mass index [BMI] gut microbiota compositions and that certain bacterial species were significantly associated with each group (obese: Blautia hydrogenotorophica, Coprococcus catus, Eubacterium ventriosum, Ruminococcus bromii, Ruminococcus obeum; non-obese: Bacteroides faecichinchillae, Bacteroides thetaiotaomicron, Blautia wexlerae, Clostridium bolteae, Flavonifractor plautii). Gut microbial properties differ between obese and non-obese subjects in Japan, suggesting that gut microbiota composition is related to obesity.

  6. Isolation and identification of anaerobic organisms from the male and female urogenital tracts.

    Science.gov (United States)

    Moss, S

    1983-06-01

    Since Bacteroides spp may play an important role together with Gardnerella vaginalis in the pathogenesis of non-specific vaginitis and balanoposthitis, anaerobic organisms were isolated and identified from 34 female and 20 male patients attending a department of genitourinary medicine, and the results compared with the clinical findings and the presence of other routinely isolated pathogens. Twenty-three different organisms were recovered from 13 of the 20 men; of these organisms, 20 were of the Bacteroides spp. Most isolates were of the B melaninogenicus/oralis group, which forms part of the commensal vaginal flora in women. A definite association between the presence of anaerobes and other pathogens needs to be firmly established, as this obviously causes important complications in treating these conditions.

  7. Frogs host faecal bacteria typically associated with humans.

    Science.gov (United States)

    Gibb, Karen; Schobben, Xavier; Christian, Keith

    2017-07-01

    Tree frogs commonly access drinking water tanks; this may have human health implications. Although amphibians might not be expected to host mammalian faecal indicator bacteria (FIB), it is possible that they may have human FIB on their skin after exposure to human waste. We collected faeces and skin wash from green tree frogs (Litoria caerulea) from a natural environment, a suburban site, and a suburban site near a creek occasionally contaminated with sewage effluent. We used molecular techniques to test for FIB that are routinely used to indicate human faecal contamination. Enterococci colonies were isolated from both faecal and skin wash samples, and specific markers (Enterococcus faecium and Bacteroides thetaiotaomicron) were found in frog faeces, demonstrating that these markers are not human- or mammalian-specific. Bacteroides thetaiotaomicron was detected in frogs from both natural and urban sites, but E. faecium was only associated with the sewage impacted site.

  8. [Microbiological changes in subgingival flora after treatment with amoxicillin-clavulanic acid].

    Science.gov (United States)

    Vallcorba Plana, N; Redondo Eleno, M; Prieto Prieto, J; Bascones Martinez, A; Cabronero, M J; Gomez Lus, M J; Sanz Alonso, M

    1989-10-01

    The association amoxicillin-clavulanic acid can be employed as an alternative to the usual antibiotic therapy of periodontitis. The purpose of this study was to determine subgingival microbial changes in 33 patients with periodontitis after using amoxicillin (500 mgrs.-t.i.d.) and clavulanic acid (125 mgrs.-t.i.d.) for 5 days. It resulted clinically in a decrease of both gingival index and plaque index (not significant) and microbiologically in absence of the main bacterial pathogens found pretreatment, such as Bacteroides melaninogenicus, Bacteroides intermedius, Eikenella corrodens and Actinomyces sp., although it was not able to eliminate Actinobacillus asinomycetemcomitans from a juvenile periodontitis and from a prepuberal periodontitis patient. Atibiotic susceptibility testing showed that all bacteria tested were sensitive to this antibiotic. Although this short term study shows good microbial response of main periodontal pathogens, long term studies are necessary to assess the effect of this antibiotic in periodontitis therapy.

  9. Antibiotic selection of Escherichia coli sequence type 131 in a mouse intestinal colonization model

    DEFF Research Database (Denmark)

    Hertz, Frederik Boetius; Løbner-Olesen, Anders; Frimodt-Møller, Niels

    2014-01-01

    day, antibiotic treatment was initiated and given subcutaneously once a day for three consecutive days. CFU of E. coli ST131, Bacteroides, and Gram-positive aerobic bacteria in fecal samples were studied, with intervals, until day 8. Bacteroides was used as an indicator organism for impact on the Gram......-negative anaerobic population. For three antibiotics, prolonged colonization was investigated with additional fecal CFU counts determined on days 10 and 14 (cefotaxime, dicloxacillin, and clindamycin). Three antibiotics (cefotaxime, dicloxacillin, and clindamycin) promoted overgrowth of E. coli ST131 (P ...The ability of different antibiotics to select for extended-spectrum β-lactamase (ESBL)-producing Escherichia coli remains a topic of discussion. In a mouse intestinal colonization model, we evaluated the selective abilities of nine common antimicrobials (cefotaxime, cefuroxime, dicloxacillin...

  10. [Antimicrobial susceptibility testing of anaerobic bacteria].

    Science.gov (United States)

    García-Sánchez, José E; García-Sánchez, Enrique; García-García, María Inmaculada

    2014-02-01

    The anaerobic bacteria resistance to antibiotics is increasing, and even has appeared against the most active of those, like metronidazol and carbapenems. This fact forces to make and periodical sensibility tests -at least in the most aggressive and virulent species, in cases that they are isolated from life locations and in the absence of therapeutic response- to check the local sensibility and to establish suitable empiric therapies, all based on multicentric studies carried out in order to this or well to check the activity of new antibiotics. For the laboratory routine, the easiest sensibility method is the E-test/MIC evaluator. Another alternative is microdilution, that's only normalized for Bacteroides. There are preliminary facts that allow the use of disc diffusion method in some species of Bacteroides and Clostridium. For the temporal and multicentric studies, the procedure is dilution in agar plate, the reference method. Copyright © 2014 Elsevier España, S.L. All rights reserved.

  11. Measurement of microbial alpha-amylases with p-nitrophenyl glycosides as the substrate complex.

    OpenAIRE

    Trepeta, R W; Edberg, S C

    1984-01-01

    The detection of alpha-amylase is commonly used in clinical microbiology laboratories to aid in differentiating Streptococcus bovis from other streptococci. It is also useful in identifying Eikenella corrodens and the gravis subspecies of Corynebacterium diphtheriae and in separating species of the genera Bacteroides, Clostridium, Actinomyces, and Bacillus. Currently, the most frequently used procedure utilizes starch as the substrate and iodine as the indicator. Starch is incorporated into a...

  12. Association of oncogenic bacteria with colorectal cancer in South China.

    Science.gov (United States)

    Zhou, Youlian; He, Hanchang; Xu, Haoming; Li, Yingfei; Li, Zhiming; Du, Yanlei; He, Jie; Zhou, Yongjian; Wang, Hong; Nie, Yuqiang

    2016-12-06

    To quantify Fusobacterium spp., Enterococcus faecalis (E.faecalis), Enterotoxigenic Bacteroides fragilis (ETBF), and Enteropathogenic Escherichia coli in colorectal cancer (CRC) patients and their possible association with CRC clinicopathogical features, we collected the resected tumors and adjacent normal tissues (N) from 97 CRC patients. 48 age- and sex-matched healthy controls (HC) were also recruited. Real-time PCR was used for bacterial quantification. The median abundance ofFusobacterium spp.(p colon tissue in the proximity of the tumor.

  13. A Bacterial Homolog of a Eukaryotic Inositol Phosphate Signaling Enzyme Mediates Cross-kingdom Dialog in the Mammalian Gut

    OpenAIRE

    Stentz, Régis; Osborne, Samantha; Horn, Nikki; Li, Arthur W.H.; Hautefort, Isabelle; Bongaerts, Roy; Rouyer, Marine; Bailey, Paul; Shears, Stephen B.; Hemmings, Andrew M.; Brearley, Charles A.; Carding, Simon R.

    2014-01-01

    Summary Dietary InsP6 can modulate eukaryotic cell proliferation and has complex nutritive consequences, but its metabolism in the mammalian gastrointestinal tract is poorly understood. Therefore, we performed phylogenetic analyses of the gastrointestinal microbiome in order to search for candidate InsP6 phosphatases. We determined that prominent gut bacteria express homologs of the mammalian InsP6 phosphatase (MINPP) and characterized the enzyme from Bacteroides thetaiotaomicron (BtMinpp). W...

  14. Influence of Forage Phenolics on Ruminal Fibrolytic Bacteria and In Vitro Fiber Degradation

    OpenAIRE

    Varel, Vincent H.; Jung, Hans-Joachim G.

    1986-01-01

    In vitro cultures of ruminal microorganisms were used to determine the effect of cinnamic acid and vanillin on the digestibility of cellulose and xylan. Cinnamic acid and vanillin depressed in vitro dry matter disappearance of cellulose 14 and 49%, respectively, when rumen fluid was the inoculum. The number of viable Bacteroides succinogenes cells, the predominant cellulolytic organism, was threefold higher for fermentations which contained vanillin than for control fermentations. When xylan ...

  15. Associations Between Microbiota, Mitochondrial Function, and Cognition in Chronic Marijuana Users.

    Science.gov (United States)

    Panee, Jun; Gerschenson, Mariana; Chang, Linda

    2018-03-01

    Marijuana (MJ) use is associated with cognitive deficits. Both mitochondrial (mt) dysfunction and gut dysbiosis also affect cognition. We examined whether cognition is related to peripheral blood mononuclear cells' (PBMCs) mt function and fecal microbiota in chronic MJ users. Nineteen chronic MJ users and 20 non-users were evaluated using the Cognition Battery in NIH Toolbox, their mt function for ATP production, and basal and maximal respirations were measured in PBMCs using the Seahorse XFe96 Analyzer, and the abundances of Prevotella and Bacteroides (associated with plant-based and animal product-based diet, respectively) were calculated from stool microbiota analysis. Average Prevotella:Bacteroides ratio was ~13-fold higher in nonusers than users. Lifetime MJ use correlated inversely with Prevotella:Bacteroides ratio (p = 0.05), mt function (p = 0.0027-0.0057), and Flanker Inhibitory Control and Attention (p = 0.041). Prevotella abundance correlated positively, while Bacteroides abundance correlated inversely, with mt function across all participants (p = 0.0004-0.06). Prevotella abundance also correlated positively with scores of Fluid Cognition, Flanker Inhibitory Control and Attention, List Sorting, and Dimension Change Card Sort in MJ users, but not in non-users (interaction-p = 0.018-0.05). Similarly, mt function correlated positively with scores of Fluid Cognition and Flanker Inhibitory Control and Attention in MJ users, but not in non-users (interaction-p = 0.0018-0.08). These preliminary findings suggest that MJ use is associated with alterations of gut microbiota and mt function, which may further contribute to cognitive deficits. We posited that MJ-associated low vegetable/fruit intake may contribute to these changes. Future studies are needed to delineate the relationships among diet, microbiota, mt function, and cognition in MJ users.

  16. Establishment of a continuous culture system for Entamoeba muris and analysis of the small subunit rRNA gene

    OpenAIRE

    Kobayashi S.; Suzuki J.; Takeuchi T.

    2009-01-01

    We established a culture system for Entamoeba muris (MG-EM-01 strain isolated from a Mongolian gerbil) using a modified Balamuth’s egg yolk infusion medium supplemented with 4% adult bovine serum and Bacteroides fragilis cocultured with Escherichia coli. Further, encystation was observed in the culture medium. The morphological characteristics of E. muris are similar to those of Entamoeba coli (E. coli); moreover, the malic isoenzyme electrophoretic band, which shows species-specific electrop...

  17. Vaginal microbiota in menopause

    OpenAIRE

    Martinus Tarina; Wresti Indriatmi; Larisa Paramitha; Evita Halim Effendi; Shannaz Nadia Yusharyahya; Hanny Nilasari

    2016-01-01

    The human vagina together with its resident, microbiota, comprise a dynamic ecosystem. Normal microbiota is dominated by Lactobacillus species, and pathogen microbiota such as Gardnerella species and Bacteroides species can occur due to decrease in Lactobacillus domination. Lactobacillus plays an essential role in keeping normal vaginal microbiota in balance. Vaginal microbiota adapts to pH change and hormonal value. Changes in the vaginal microbiota over a woman’s lifespan will influence the...

  18. Influencia del estrógeno en la enfermedad periodontal: revisión de literatura

    OpenAIRE

    V.F.C. Pazmino; N.Z. Assem; E.P. Pellizzer; J.M. De Almeida; L.H. Theodoro

    2015-01-01

    La etiología de la enfermedad periodontal está bien definida, dentro de los agentes etiológicos que la causan podemos citar algunos microorganismos subgingivales como: Porphyromonas gingivalis, Prevotella intermedia, Bacteroides forsythus, Actinobacillus actinomycetemcomitans y espiroquetas. La susceptibilidad del huésped a estos agentes bacterianos también tiene un papel importante dentro del progreso y prevalencia de la enfermedad periodontal. Dentro de los factores de riesgo asociados con ...

  19. United States Air Force Graduate Student Research Program. Program Technical rept. Volume 3

    Science.gov (United States)

    1988-12-01

    contents of twenty adult meat-fed Wistar rats were combined with a suspension of Bacteroides distasonis and Streptococcus faecalis and injected...and chocolate agar plates were used to culture the bacteria necessary for this experiment. Inoculum- Streptococcus faecalis (ATCC 299T) * Streptococcus ...Random Medium 99 Synchronization of the Chlamydomonas Mary Ritter reinhardtii cell cycle through light-dark cycling for subsequent testing with infra

  20. A hybrid two-component system protein of a prominent human gut symbiont couples glycan sensing in vivo to carbohydrate metabolism

    OpenAIRE

    Sonnenburg, Erica D.; Sonnenburg, Justin L.; Manchester, Jill K.; Hansen, Elizabeth E.; Chiang, Herbert C.; Gordon, Jeffrey I.

    2006-01-01

    Bacteroides thetaiotaomicron is a prominent member of our normal adult intestinal microbial community and a useful model for studying the foundations of human–bacterial mutualism in our densely populated distal gut microbiota. A central question is how members of this microbiota sense nutrients and implement an appropriate metabolic response. B. thetaiotaomicron contains a large number of glycoside hydrolases not represented in our own proteome, plus a markedly expanded collection of hybrid t...

  1. Molecular genetic studies on obligate anaerobic bacteria

    International Nuclear Information System (INIS)

    Woods, D.R.

    1982-01-01

    Molecular genetic studies on obligate anaerobic bacteria have lagged behind similar studies in aerobes. However, the current interest in biotechnology, the involvement of anaerobes in disease and the emergence of antibioticresistant strains have focused attention on the genetics of anaerobes. This article reviews molecular genetic studies in Bacteroides spp., Clostridium spp. and methanogens. Certain genetic systems in some anaerobes differ from those in aerobes and illustrate the genetic diversity among bacteria

  2. Cloning and Biochemical Characterization of a Class A β-Lactamase from Prevotella intermedia

    Science.gov (United States)

    Madinier, I.; Fosse, T.; Giudicelli, J.; Labia, R.

    2001-01-01

    The gene encoding a β-lactamase of Prevotella intermedia was cloned and sequenced. This gene, called cfxA2, shared 98% identity with cfxA, the structural gene of a β-lactamase previously described in Bacteroides vulgatus. The deduced protein sequence had a K272E substitution. CfxA2 had the characteristics of class A, group 2e β-lactamases. PMID:11451705

  3. Malic Enzyme Cofactor and Domain Requirements for Symbiotic N2 Fixation by Sinorhizobium meliloti▿ †

    Science.gov (United States)

    Mitsch, Michael J.; Cowie, Alison; Finan, Turlough M.

    2007-01-01

    The NAD+-dependent malic enzyme (DME) and the NADP+-dependent malic enzyme (TME) of Sinorhizobium meliloti are representatives of a distinct class of malic enzymes that contain a 440-amino-acid N-terminal region homologous to other malic enzymes and a 330-amino-acid C-terminal region with similarity to phosphotransacetylase enzymes (PTA). We have shown previously that dme mutants of S. meliloti fail to fix N2 (Fix−) in alfalfa root nodules, whereas tme mutants are unimpaired in their N2-fixing ability (Fix+). Here we report that the amount of DME protein in bacteroids is 10 times greater than that of TME. We therefore investigated whether increased TME activity in nodules would allow TME to function in place of DME. The tme gene was placed under the control of the dme promoter, and despite elevated levels of TME within bacteroids, no symbiotic nitrogen fixation occurred in dme mutant strains. Conversely, expression of dme from the tme promoter resulted in a large reduction in DME activity and symbiotic N2 fixation. Hence, TME cannot replace the symbiotic requirement for DME. In further experiments we investigated the DME PTA-like domain and showed that it is not required for N2 fixation. Thus, expression of a DME C-terminal deletion derivative or the Escherichia coli NAD+-dependent malic enzyme (sfcA), both of which lack the PTA-like region, restored wild-type N2 fixation to a dme mutant. Our results have defined the symbiotic requirements for malic enzyme and raise the possibility that a constant high ratio of NADPH + H+ to NADP in nitrogen-fixing bacteroids prevents TME from functioning in N2-fixing bacteroids. PMID:17071765

  4. Malic enzyme cofactor and domain requirements for symbiotic N2 fixation by Sinorhizobium meliloti.

    Science.gov (United States)

    Mitsch, Michael J; Cowie, Alison; Finan, Turlough M

    2007-01-01

    The NAD(+)-dependent malic enzyme (DME) and the NADP(+)-dependent malic enzyme (TME) of Sinorhizobium meliloti are representatives of a distinct class of malic enzymes that contain a 440-amino-acid N-terminal region homologous to other malic enzymes and a 330-amino-acid C-terminal region with similarity to phosphotransacetylase enzymes (PTA). We have shown previously that dme mutants of S. meliloti fail to fix N(2) (Fix(-)) in alfalfa root nodules, whereas tme mutants are unimpaired in their N(2)-fixing ability (Fix(+)). Here we report that the amount of DME protein in bacteroids is 10 times greater than that of TME. We therefore investigated whether increased TME activity in nodules would allow TME to function in place of DME. The tme gene was placed under the control of the dme promoter, and despite elevated levels of TME within bacteroids, no symbiotic nitrogen fixation occurred in dme mutant strains. Conversely, expression of dme from the tme promoter resulted in a large reduction in DME activity and symbiotic N(2) fixation. Hence, TME cannot replace the symbiotic requirement for DME. In further experiments we investigated the DME PTA-like domain and showed that it is not required for N(2) fixation. Thus, expression of a DME C-terminal deletion derivative or the Escherichia coli NAD(+)-dependent malic enzyme (sfcA), both of which lack the PTA-like region, restored wild-type N(2) fixation to a dme mutant. Our results have defined the symbiotic requirements for malic enzyme and raise the possibility that a constant high ratio of NADPH + H(+) to NADP in nitrogen-fixing bacteroids prevents TME from functioning in N(2)-fixing bacteroids.

  5. NAD(P)+-malic enzyme mutants of Sinorhizobium sp. strain NGR234, but not Azorhizobium caulinodans ORS571, maintain symbiotic N2 fixation capabilities.

    Science.gov (United States)

    Zhang, Ye; Aono, Toshihiro; Poole, Phillip; Finan, Turlough M

    2012-04-01

    C(4)-dicarboxylic acids appear to be metabolized via the tricarboxylic acid (TCA) cycle in N(2)-fixing bacteria (bacteroids) within legume nodules. In Sinorhizobium meliloti bacteroids from alfalfa, NAD(+)-malic enzyme (DME) is required for N(2) fixation, and this activity is thought to be required for the anaplerotic synthesis of pyruvate. In contrast, in the pea symbiont Rhizobium leguminosarum, pyruvate synthesis occurs via either DME or a pathway catalyzed by phosphoenolpyruvate carboxykinase (PCK) and pyruvate kinase (PYK). Here we report that dme mutants of the broad-host-range Sinorhizobium sp. strain NGR234 formed nodules whose level of N(2) fixation varied from 27 to 83% (plant dry weight) of the wild-type level, depending on the host plant inoculated. NGR234 bacteroids had significant PCK activity, and while single pckA and single dme mutants fixed N(2) at reduced rates, a pckA dme double mutant had no N(2)-fixing activity (Fix(-)). Thus, NGR234 bacteroids appear to synthesize pyruvate from TCA cycle intermediates via DME or PCK pathways. These NGR234 data, together with other reports, suggested that the completely Fix(-) phenotype of S. meliloti dme mutants may be specific to the alfalfa-S. meliloti symbiosis. We therefore examined the ME-like genes azc3656 and azc0119 from Azorhizobium caulinodans, as azc3656 mutants were previously shown to form Fix(-) nodules on the tropical legume Sesbania rostrata. We found that purified AZC3656 protein is an NAD(P)(+)-malic enzyme whose activity is inhibited by acetyl-coenzyme A (acetyl-CoA) and stimulated by succinate and fumarate. Thus, whereas DME is required for symbiotic N(2) fixation in A. caulinodans and S. meliloti, in other rhizobia this activity can be bypassed via another pathway(s).

  6. Predicting fecal sources in waters with diverse pollution loads using general and molecular host-specific indicators and applying machine learning methods

    OpenAIRE

    Casanovas Massana, Arnau; Gómez Doñate, Marta; Sánchez, David; Belanche Muñoz, Luis Antonio; Muniesa, Maite; Blanch, Anicet R.

    2015-01-01

    In this study we use a machine learning software (Ichnaea) to generate predictive models for water samples with different concentrations of fecal contamination (point source, moderate and low). We applied several MST methods (host-specific Bacteroides phages, mitochondrial DNA genetic markers, Bifidobacterium adolescentis and Bifidobacterium dentium markers, and bifidobacterial host-specific qPCR), and general indicators (Escherichia colt, enterococci and somatic coliphages) to evaluate the s...

  7. Integrated analysis of established and novel microbial and chemical methods for microbial source tracking.

    Science.gov (United States)

    Blanch, Anicet R; Belanche-Muñoz, Lluís; Bonjoch, Xavier; Ebdon, James; Gantzer, Christophe; Lucena, Francisco; Ottoson, Jakob; Kourtis, Christos; Iversen, Aina; Kühn, Inger; Mocé, Laura; Muniesa, Maite; Schwartzbrod, Janine; Skraber, Sylvain; Papageorgiou, Georgios T; Taylor, Huw; Wallis, Jessica; Jofre, Joan

    2006-09-01

    Several microbes and chemicals have been considered as potential tracers to identify fecal sources in the environment. However, to date, no one approach has been shown to accurately identify the origins of fecal pollution in aquatic environments. In this multilaboratory study, different microbial and chemical indicators were analyzed in order to distinguish human fecal sources from nonhuman fecal sources using wastewaters and slurries from diverse geographical areas within Europe. Twenty-six parameters, which were later combined to form derived variables for statistical analyses, were obtained by performing methods that were achievable in all the participant laboratories: enumeration of fecal coliform bacteria, enterococci, clostridia, somatic coliphages, F-specific RNA phages, bacteriophages infecting Bacteroides fragilis RYC2056 and Bacteroides thetaiotaomicron GA17, and total and sorbitol-fermenting bifidobacteria; genotyping of F-specific RNA phages; biochemical phenotyping of fecal coliform bacteria and enterococci using miniaturized tests; specific detection of Bifidobacterium adolescentis and Bifidobacterium dentium; and measurement of four fecal sterols. A number of potentially useful source indicators were detected (bacteriophages infecting B. thetaiotaomicron, certain genotypes of F-specific bacteriophages, sorbitol-fermenting bifidobacteria, 24-ethylcoprostanol, and epycoprostanol), although no one source identifier alone provided 100% correct classification of the fecal source. Subsequently, 38 variables (both single and derived) were defined from the measured microbial and chemical parameters in order to find the best subset of variables to develop predictive models using the lowest possible number of measured parameters. To this end, several statistical or machine learning methods were evaluated and provided two successful predictive models based on just two variables, giving 100% correct classification: the ratio of the densities of somatic

  8. The susceptibility of organisms associated with bacterial vaginosis to spermicidal compounds, in vitro.

    Science.gov (United States)

    Jones, B M; Willcox, L M

    1991-01-01

    OBJECTIVES--Bacterial vaginosis (BV) is a prevalent vaginal infection that is now regarded as a risk factor in more serious pelvic and obstetric complications. Spermicides are known to have antimicrobial activity against other sexually transmitted diseases and the aim of this study was to test whether the causative organisms of BV were also susceptible to spermicides, in vitro. DESIGN--Minimal Inhibitory Concentrations of five spermicidal compounds were determined for the organisms associated with BV, in an agar dilution technique. LOCATION--The Department of Experimental and Clinical Microbiology, University of Sheffield Medical School, UK. SPERMICIDES AND ORGANISMS--Nonoxynol-9, Nonoxynol-11, Docusate sodium, Benzalkonium chloride and Menfegol were tested against 20 strains each of Gardnerella vaginalis, Bacteroides and Mobiluncus organisms, isolated from patients with BV who attended the Department of Genitourinary Medicine, the Royal Hallamshire Hospital, Sheffield. MAIN OUTCOME MEASURES--The susceptibility of BV-associated organisms to spermicidal compounds, in vitro. RESULTS--G vaginalis, Mobiluncus spp, Bacteroides bivius and Bacteroides disiens were all susceptible to the five spermicides tested, with MICs ranging between less than or equal to 19 and 5000 mg/l (0.0019%-0.5%). CONCLUSION--The concentrations of spermicides incorporated in contraceptive preparations are usually between 3% and 8%, which are far in excess of the MICs found for BV organisms. Their usage could exert a significant antimicrobial effect and be a useful prophylactic in preventing the infection. PMID:1774052

  9. Isoenzymes of superoxide dismutase in nodules of Phaseolus vulgaris L. , Pisum sativum L. , and Vigna unguiculata (L. ) Walp

    Energy Technology Data Exchange (ETDEWEB)

    Becana, M.; Paris, F.J.; Sandalio, L.M.; Del Rio, L.A. (IRNA, Salamanca (Spain) Unidad de Bioquimica Vegetal, Granada (Spain))

    1989-08-01

    The activity and isozymic composition of superoxide dismutase were determined in nodules of Phaseolus vulgaris L., Pisum sativum L., and Vigna unguiculata (L.) Walp. A Mn-SOD was present in Rhizobium and two in Bradyrhizobium and bacteroids. Nodule mitochondria from all three legume species had a single Mn-SOD with similar relative mobility, whereas the cytosol contained several CuZn-SODs: two in Phaseolus and Pisum, and four in Vigna. In the cytoplasm of V. unguiculata nodules, a Fe-containing SOD was also present, with an electrophoretic mobility between those of CuZn- and Mn-SODs, and an estimated molecular weight of 57,000. Total SOD activity of the soluble fraction of host cells, expressed on a nodule fresh weight basis, exceeded markedly that of bacteroids. Likewise, specific SOD activities of free-living bacteria were superior or equal to those of their symbiotic forms. Soluble extracts of bacteria and bacteroids did not show peroxidase activity, but the nodule cell cytoplasm contained diverse peroxidase isozymes which were readily distinguishable from leghemoglobin components by electrophoresis. Data indicated that peroxidases and leghemoglobins did not significantly interfere with SOD localization on gels. Treatment with chloroform-ethanol scarcely affected the isozymic pattern of SODs and peroxidases, and had limited success in the removal of leghemoglobin.

  10. Symbiosomes: temporary moonlighting organelles.

    Science.gov (United States)

    Emerich, David W; Krishnan, Hari B

    2014-05-15

    Symbiosomes are a unique structural entity that performs the role of biological nitrogen fixation, an energy-demanding process that is the primary entryway of fixed nitrogen into the biosphere. Symbiosomes result from the infection of specific rhizobial strains into the roots of an appropriate leguminous host plant forming an organ referred to as a nodule. Within the infected plant cells of the nodule, the rhizobia are encased within membrane-bounded structures that develop into symbiosomes. Mature symbiosomes create an environment that allows the rhizobia to differentiate into a nitrogen-fixing form called bacteroids. The bacteroids are surrounded by the symbiosome space, which is populated by proteins from both eukaryotic and prokaryotic symbionts, suggesting this space is the quintessential component of symbiosis: an inter-kingdom environment with the single purpose of symbiotic nitrogen fixation. Proteins associated with the symbiosome membrane are largely plant-derived proteins and are non-metabolic in nature. The proteins of the symbiosome space are mostly derived from the bacteroid with annotated functions of carbon metabolism, whereas relatively few are involved in nitrogen metabolism. An appreciable portion of both the eukaryotic and prokaryotic proteins in the symbiosome are also 'moonlighting' proteins, which are defined as proteins that perform roles unrelated to their annotated activities when found in an unexpected physiological environment. The essential functions of symbiotic nitrogen fixation of the symbiosome are performed by co-operative interactions of proteins from both symbionts some of which may be performing unexpected roles.

  11. Gut Microbiota in Health, Diverticular Disease, Irritable Bowel Syndrome, and Inflammatory Bowel Diseases: Time for Microbial Marker of Gastrointestinal Disorders.

    Science.gov (United States)

    Lopetuso, Loris Riccardo; Petito, Valentina; Graziani, Cristina; Schiavoni, Elisa; Paroni Sterbini, Francesco; Poscia, Andrea; Gaetani, Eleonora; Franceschi, Francesco; Cammarota, Giovanni; Sanguinetti, Maurizio; Masucci, Luca; Scaldaferri, Franco; Gasbarrini, Antonio

    2018-01-01

    Few data exist on differences in gut microbiota composition among principal gastrointestinal (GI) diseases. We evaluated the differences in gut microbiota composition among uncomplicated diverticular disease (DD), irritable bowel syndrome (IBS) and inflammatory bowel diseases (IBD) patients. DD, IBS, and IBD patients along with healthy controls (CT) were enrolled in our Italian GI outpatient clinic. Stool samples were collected. Microbiota composition was evaluated through a metagenomic gene-targeted approach. GI pathology represented a continuous spectrum of diseases where IBD displayed one extreme, while CT displayed the other. Among Phyla, Biplot PC2/PC3 and dendogram plot showed major differences in samples from IBS and IBD. DD resembled species CT composition, but not for Bacteroides fragilis. In IBS, Dialister spp. and then Faecalibacterium prausnitzii were the most representative species. Ulcerative colitis showed a reduced concentration of Clostridium difficile and an increase of Bacteroides fragilis. In Crohn's disease, Parabacteroides distasonis was the most represented, while Faecalibacterium prausnitzii and Bacteroides fragilis were significantly reduced. Each disorder has its definite overall microbial signature, which produces a clear differentiation from the others. On the other hand, shared alterations constitute the "core dysbiosis" of GI diseases. The assessment of these microbial markers represents a parameter that may complete the diagnostic assessment. © 2017 S. Karger AG, Basel.

  12. Microbiome analysis of stool samples from African Americans with colon polyps.

    Science.gov (United States)

    Brim, Hassan; Yooseph, Shibu; Zoetendal, Erwin G; Lee, Edward; Torralbo, Manolito; Laiyemo, Adeyinka O; Shokrani, Babak; Nelson, Karen; Ashktorab, Hassan

    2013-01-01

    Colonic polyps are common tumors occurring in ~50% of Western populations with ~10% risk of malignant progression. Dietary agents have been considered the primary environmental exposure to promote colorectal cancer (CRC) development. However, the colonic mucosa is permanently in contact with the microbiota and its metabolic products including toxins that also have the potential to trigger oncogenic transformation. To analyze fecal DNA for microbiota composition and functional potential in African Americans with pre-neoplastic lesions. We analyzed the bacterial composition of stool samples from 6 healthy individuals and 6 patients with colon polyps using 16S ribosomal RNA-based phylogenetic microarray; the Human intestinal Tract Chip (HITChip) and 16S rRNA gene barcoded 454 pyrosequencing. The functional potential was determined by sequence-based metagenomics using 454 pyrosequencing. Fecal microbiota profiling of samples from the healthy and polyp patients using both a phylogenetic microarraying (HITChip) and barcoded 454 pyrosequencing generated similar results. A distinction between both sets of samples was only obtained when the analysis was performed at the sub-genus level. Most of the species leading to the dissociation were from the Bacteroides group. The metagenomic analysis did not reveal major differences in bacterial gene prevalence/abundances between the two groups even when the analysis and comparisons were restricted to available Bacteroides genomes. This study reveals that at the pre-neoplastic stages, there is a trend showing microbiota changes between healthy and colon polyp patients at the sub-genus level. These differences were not reflected at the genome/functions levels. Bacteria and associated functions within the Bacteroides group need to be further analyzed and dissected to pinpoint potential actors in the early colon oncogenic transformation in a large sample size.

  13. Microbiome analysis of stool samples from African Americans with colon polyps.

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    Hassan Brim

    Full Text Available Colonic polyps are common tumors occurring in ~50% of Western populations with ~10% risk of malignant progression. Dietary agents have been considered the primary environmental exposure to promote colorectal cancer (CRC development. However, the colonic mucosa is permanently in contact with the microbiota and its metabolic products including toxins that also have the potential to trigger oncogenic transformation.To analyze fecal DNA for microbiota composition and functional potential in African Americans with pre-neoplastic lesions.We analyzed the bacterial composition of stool samples from 6 healthy individuals and 6 patients with colon polyps using 16S ribosomal RNA-based phylogenetic microarray; the Human intestinal Tract Chip (HITChip and 16S rRNA gene barcoded 454 pyrosequencing. The functional potential was determined by sequence-based metagenomics using 454 pyrosequencing.Fecal microbiota profiling of samples from the healthy and polyp patients using both a phylogenetic microarraying (HITChip and barcoded 454 pyrosequencing generated similar results. A distinction between both sets of samples was only obtained when the analysis was performed at the sub-genus level. Most of the species leading to the dissociation were from the Bacteroides group. The metagenomic analysis did not reveal major differences in bacterial gene prevalence/abundances between the two groups even when the analysis and comparisons were restricted to available Bacteroides genomes.This study reveals that at the pre-neoplastic stages, there is a trend showing microbiota changes between healthy and colon polyp patients at the sub-genus level. These differences were not reflected at the genome/functions levels. Bacteria and associated functions within the Bacteroides group need to be further analyzed and dissected to pinpoint potential actors in the early colon oncogenic transformation in a large sample size.

  14. Occurrence of polyamines in root nodules of Phaseolus vulgaris in symbiosis with Rhizobium tropici in response to salt stress.

    Science.gov (United States)

    López-Gómez, Miguel; Cobos-Porras, Libertad; Hidalgo-Castellanos, Javier; Lluch, Carmen

    2014-11-01

    Polyamines (PAs) are low molecular weight aliphatic compounds that have been shown to be an important part of plant responses to salt stress. For that reason in this work we have investigated the involvement of PAs in the response to salt stress in root nodules of Phaseolus vulgaris in symbiosis with Rhizobium tropici. The level and variety of PAs was higher in nodules, compared to leaves and roots, and in addition to the common PAs (putrescine, spermidine and spermine) we found homospermidine (Homspd) as the most abundant polyamine in nodules. UPLC-mass spectrometry analysis revealed the presence of 4-aminobutylcadaverine (4-ABcad), only described in nodules of Vigna angularis before. Indeed, the analysis of different nodular fractions revealed higher level of 4-ABcad, as well as Homspd, in bacteroids which indicate the production of these PAs by the bacteria in symbiosis. The genes involved in PAs biosynthesis in nodules displayed an induction under salt stress conditions which was not consistent with the decline of free PAs levels, probably due to the nitrogen limitations provoked by the nitrogenase activity depletion and/or the conversion of free PAs to theirs soluble conjugated forms, that seems to be one of the mechanisms involved in the regulation of PAs levels. On the contrary, cadaverine (Cad) and 4-ABcad concentrations augmented by the salinity, which might be due to their involvement in the response of bacteroids to hyper-osmotic conditions. In conclusion, the results shown in this work suggest the alteration of the bacteroidal metabolism towards the production of uncommon PAs such as 4-ABcad in the response to salt stress in legume root nodules. Copyright © 2014 Elsevier Ltd. All rights reserved.

  15. A comparative study on the effects of tylosin on select bacteria during continuous flow culture of mixed populations of gut microflora derived from a feral and a domestic pig.

    Science.gov (United States)

    Ramlachan, Nicole; Anderson, Robin C; Andrews, Kathleen; Harvey, Roger B; Nisbet, David J

    2008-02-01

    Continuous flow cultures of feral (culture FC) and domesticated (culture RPCF) pig gut microflora were established in steady state. Cultures were continuously infused with 25 or 100 microg tylosin/mL and sampled at intervals to assess effects on total culturable anaerobes, Bacteroides and Enterococcus via plating to agar supplemented without or with 100 microg tylosin/mL, the latter to assess bacterial sensitivity to tylosin. Endogenous tylosin-insensitive anaerobes within the cultures, while similar prior to tylosin administration, responded differently during tylosin administration, with concentrations in RPCF cultures becoming enriched more than in FC cultures. Tylosin-insensitive anaerobes in RPCF cultures persisted at increased concentrations after cessation of tylosin administration whereas concentrations in FC cultures decreased slightly. Concentrations of Bacteroides and endogenous Enterococcus recovered on medium without tylosin decreased to near or below detectable levels in FC cultures administered 25 or 100 microg tylosin/mL. Tylosin-insensitive Bacteroides were enriched to >5 log10 CFU/mL in RPCF cultures after 25 microg tylosin/mL but not at 100 microg tylosin/mL. Populations of endogenous tylosin-insensitive Enterococcus were enriched in RPCF but not FC cultures administered 25 or 100 microg tylosin/mL. In cultures administered 100 microg tylosin/mL, an exogenous-sourced E. faecium possessing tylosin resistance maintained itself only in the presence of tylosin. These results indicate that under the conditions of these tests, antibiotic exposure may enrich for antibiotic-insensitive bacteria populations of endogenous or exogenous origin but that the ability of an exogenous tylosin-resistant E. faecium to persist is reduced in the absence of the antibiotic, likely due to exclusion by native flora.

  16. More than meets the eye: associations of vaginal bacteria with gram stain morphotypes using molecular phylogenetic analysis.

    Directory of Open Access Journals (Sweden)

    Sujatha Srinivasan

    Full Text Available Bacterial vaginosis (BV is a highly prevalent condition associated with adverse health outcomes. Gram stain analysis of vaginal fluid is the standard for confirming the diagnosis of BV, wherein abundances of key bacterial morphotypes are assessed. These Lactobacillus, Gardnerella, Bacteroides, and Mobiluncus morphotypes were originally linked to particular bacterial species through cultivation studies, but no studies have systematically investigated associations between uncultivated bacteria detected by molecular methods and Gram stain findings. In this study, 16S-rRNA PCR/pyrosequencing was used to examine associations between vaginal bacteria and bacterial morphotypes in 220 women with and without BV. Species-specific quantitative PCR (qPCR and fluorescence in Situ hybridization (FISH methods were used to document concentrations of two bacteria with curved rod morphologies: Mobiluncus and the fastidious BV-associated bacterium-1 (BVAB1. Rank abundance of vaginal bacteria in samples with evidence of curved gram-negative rods showed that BVAB1 was dominant (26.1%, while Mobiluncus was rare (0.2% of sequence reads. BVAB1 sequence reads were associated with Mobiluncus morphotypes (p<0.001. Among women with curved rods, mean concentration of BVAB1 DNA was 2 log units greater than Mobiluncus (p<0.001 using species-specific quantitative PCR. FISH analyses revealed that mean number of BVAB1 cells was 2 log units greater than Mobiluncus cells in women with highest Nugent score (p<0.001. Prevotella and Porphyromonas spp. were significantly associated with the "Bacteroides morphotype," whereas Bacteroides species were rare. Gram-negative rods designated Mobiluncus morphotypes on Gram stain are more likely BVAB1. These findings provide a clearer picture of the bacteria associated with morphotypes on vaginal Gram stain.

  17. Gut microbiota composition in male rat models under different nutritional status and physical activity and its association with serum leptin and ghrelin levels.

    Science.gov (United States)

    Queipo-Ortuño, María Isabel; Seoane, Luisa María; Murri, Mora; Pardo, María; Gomez-Zumaquero, Juan Miguel; Cardona, Fernando; Casanueva, Felipe; Tinahones, Francisco J

    2013-01-01

    Several evidences indicate that gut microbiota is involved in the control of host energy metabolism. To evaluate the differences in the composition of gut microbiota in rat models under different nutritional status and physical activity and to identify their associations with serum leptin and ghrelin levels. In a case control study, forty male rats were randomly assigned to one of these four experimental groups: ABA group with food restriction and free access to exercise; control ABA group with food restriction and no access to exercise; exercise group with free access to exercise and feed ad libitum and ad libitum group without access to exercise and feed ad libitum. The fecal bacteria composition was investigated by PCR-denaturing gradient gel electrophoresis and real-time qPCR. In restricted eaters, we have found a significant increase in the number of Proteobacteria, Bacteroides, Clostridium, Enterococcus, Prevotella and M. smithii and a significant decrease in the quantities of Actinobacteria, Firmicutes, Bacteroidetes, B. coccoides-E. rectale group, Lactobacillus and Bifidobacterium with respect to unrestricted eaters. Moreover, a significant increase in the number of Lactobacillus, Bifidobacterium and B. coccoides-E. rectale group was observed in exercise group with respect to the rest of groups. We also found a significant positive correlation between the quantity of Bifidobacterium and Lactobacillus and serum leptin levels, and a significant and negative correlation among the number of Clostridium, Bacteroides and Prevotella and serum leptin levels in all experimental groups. Furthermore, serum ghrelin levels were negatively correlated with the quantity of Bifidobacterium, Lactobacillus and B. coccoides-Eubacterium rectale group and positively correlated with the number of Bacteroides and Prevotella. Nutritional status and physical activity alter gut microbiota composition affecting the diversity and similarity. This study highlights the associations

  18. Gut microbiome in children with enthesitis-related arthritis in a developing country and the effect of probiotic administration.

    Science.gov (United States)

    Aggarwal, A; Sarangi, A N; Gaur, P; Shukla, A; Aggarwal, R

    2017-03-01

    In Asia, enthesitis-related arthritis (ERA) is the most frequent category of juvenile idiopathic arthritis. ERA has a strong association with human leucocyte antigen (HLA)-B27 and subclinical gut inflammation. In an HLA-B27 transgenic rat model, the presence of Bacteroides bacteria in the gut appears to cause spondyloarthropathy (SpA). Thus, we studied gut microbiota in children with ERA. Stool specimens from 33 patients with ERA and 14 age-matched healthy controls were studied; none had any gastrointestinal symptom, or had received a drug known to affect gut motility or microbiota in the preceding 6 weeks. From each specimen, a cDNA library for the V3 region of bacterial 16S rRNA was subjected to high-throughput, massively parallel sequencing. Relationship of the specimens was studied using principal co-ordinate analysis (PCoA), and abundances of various bacterial taxa and alpha diversity were compared between groups. In eight patients, a repeat faecal specimen was studied after 12 weeks of probiotic therapy. The 55 specimens yielded a median (range) of 397 315 (102 093-1 502 380) high-quality reads each. In PCoA, gut microbiota from ERA showed a wider dispersion than those from controls. In patients, families Bacteroidaceae and Enterobacteriaceae were more abundant and Prevotellaceae were less abundant than in controls. Also, genera Bacteroides, Entercoccus and Klebsiella were over-represented and genus Prevotella was under-represented in ERA patients. Probiotic therapy led to a non-significant increase in Prevotellaceae. Patients with ERA have a dysbiosis in the gut, with increased abundance of Bacteroides and reduction of Prevotella. Probiotic supplementation in a subset of patients did not reverse these changes significantly. © 2016 British Society for Immunology.

  19. Alfalfa nodules elicited by a flavodoxin-overexpressing Ensifer meliloti strain display nitrogen-fixing activity with enhanced tolerance to salinity stress.

    Science.gov (United States)

    Redondo, Francisco J; Coba de la Peña, Teodoro; Lucas, M Mercedes; Pueyo, José J

    2012-12-01

    Nitrogen fixation by legumes is very sensitive to salinity stress, which can severely reduce the productivity of legume crops and their soil-enriching capacity. Salinity is known to cause oxidative stress in the nodule by generating reactive oxygen species (ROS). Flavodoxins are involved in the response to oxidative stress in bacteria and cyanobacteria. Prevention of ROS production by flavodoxin overexpression in bacteroids might lead to a protective effect on nodule functioning under salinity stress. Tolerance to salinity stress was evaluated in alfalfa nodules elicited by an Ensifer meliloti strain that overexpressed a cyanobacterial flavodoxin compared with nodules produced by the wild-type bacteria. Nitrogen fixation, antioxidant and carbon metabolism enzyme activities were determined. The decline in nitrogenase activity associated to salinity stress was significantly less in flavodoxin-expressing than in wild-type nodules. We detected small but significant changes in nodule antioxidant metabolism involving the ascorbate-glutathione cycle enzymes and metabolites, as well as differences in activity of the carbon metabolism enzyme sucrose synthase, and an atypical starch accumulation pattern in flavodoxin-containing nodules. Salt-induced structural and ultrastructural alterations were examined in detail in alfalfa wild-type nodules by light and electron microscopy and compared to flavodoxin-containing nodules. Flavodoxin reduced salt-induced structural damage, which primarily affected young infected tissues and not fully differentiated bacteroids. The results indicate that overexpression of flavodoxin in bacteroids has a protective effect on the function and structure of alfalfa nodules subjected to salinity stress conditions. Putative protection mechanisms are discussed.

  20. Identification and characterization of the intracellular poly-3-hydroxybutyrate depolymerase enzyme PhaZ of Sinorhizobium meliloti

    Directory of Open Access Journals (Sweden)

    Zachertowska Alicja

    2010-03-01

    Full Text Available Abstract Background S. meliloti forms indeterminate nodules on the roots of its host plant alfalfa (Medicago sativa. Bacteroids of indeterminate nodules are terminally differentiated and, unlike their non-terminally differentiated counterparts in determinate nodules, do not accumulate large quantities of Poly-3-hydroxybutyrate (PHB during symbiosis. PhaZ is in intracellular PHB depolymerase; it represents the first enzyme in the degradative arm of the PHB cycle in S. meliloti and is the only enzyme in this half of the PHB cycle that remains uncharacterized. Results The S. meliloti phaZ gene was identified by in silico analysis, the ORF was cloned, and a S. meliloti phaZ mutant was constructed. This mutant exhibited increased PHB accumulation during free-living growth, even when grown under non-PHB-inducing conditions. The phaZ mutant demonstrated no reduction in symbiotic capacity; interestingly, analysis of the bacteroids showed that this mutant also accumulated PHB during symbiosis. This mutant also exhibited a decreased capacity to tolerate long-term carbon starvation, comparable to that of other PHB cycle mutants. In contrast to other PHB cycle mutants, the S. meliloti phaZ mutant did not exhibit any decrease in rhizosphere competitiveness; however, this mutant did exhibit a significant increase in succinoglycan biosynthesis. Conclusions S. meliloti bacteroids retain the capacity to synthesize PHB during symbiosis; interestingly, accumulation does not occur at the expense of symbiotic performance. phaZ mutants are not compromised in their capacity to compete for nodulation in the rhizosphere, perhaps due to increased succinoglycan production resulting from upregulation of the succinoglycan biosynthetic pathway. The reduced survival capacity of free-living cells unable to access their accumulated stores of PHB suggests that PHB is a crucial metabolite under adverse conditions.

  1. Microbial Community of Healthy Thai Vegetarians and Non-Vegetarians, Their Core Gut Microbiota, and Pathogen Risk.

    Science.gov (United States)

    Ruengsomwong, Supatjaree; La-Ongkham, Orawan; Jiang, Jiahui; Wannissorn, Bhusita; Nakayama, Jiro; Nitisinprasert, Sunee

    2016-10-28

    Pyrosequencing analysis of intestinal microflora from healthy Thai vegetarians and non-vegetarians exhibited 893 OTUs covering 189 species. The strong species indicators of vegetarians and non-vegetarians were Prevotella copri and Bacteroides vulgatus as well as bacteria close to Escherichia hermanii with % relative abundance of 16.9 and 4.5-4.7, respectively. Core gut microbiota of the vegetarian and non-vegetarian groups consisted of 11 and 20 different bacterial species, respectively, belonging to Actinobacteria, Firmicutes, and Proteobacteria commonly found in both groups. Two species, Faecalibacterium prausnitzii and Gemmiger formicilis , had a prevalence of 100% in both groups. Three species, Clostridium nexile , Eubacterium eligens , and P. copri , showed up in most vegetarians, whereas more diversity of Collinsella aerofaciens , Ruminococcus torques , various species of Bacteroides , Parabacteroides , Escherichia , and different species of Clostridium and Eubacterium were found in most non-vegetarians. Considering the correlation of personal characters, consumption behavior, and microbial groups, the age of non-vegetarians showed a strong positive correlation coefficient of 0.54 ( p = 0.001) to Bacteroides uniformis but exhibited a moderate one to Alistipes finegoldii and B. vulgatus . Only a positive moderate correlation of body mass index and Parabacteroides distasonis appeared. Based on the significant abundance of potential pathogens, the microbiota of the non-vegetarian group showed an abundance of potential pathogen varieties of Bilophila wadsworthia , Escherichia coli , and E. hermannii , whereas that of the vegetarian group served for only Klebsiella pneumoniae . These results implied that the microbiota of vegetarians with high abundance of P. copri and low potential pathogen variety would be a way to maintain good health in Thais.

  2. Eficacia y mecanismos de acción de bacterias intestinales en alteraciones metabólicas e inmunológicas asociadas a la obesidad y al estrés

    OpenAIRE

    Moya Perez, Angela

    2015-01-01

    El objetivo general de la presente Tesis ha sido analizar la contribución de la microbiota intestinal a la función del sistema inmune, metabolismo, Sistema Nervioso Central y evaluar el efecto de potenciales probióticos en modelos animales de obesidad y ansiedad inducida por estrés. Los objetivos concretos han sido los siguientes: 1. Evaluar la eficacia de Bacteroides uniformis CECT 7771 en un modelo murino de obesidad inducida por la dieta. 2. Identificar el mecanismo de acción d...

  3. Tissue-associated bacterial alterations in rectal carcinoma patients revealed by 16S rRNA community profiling

    Directory of Open Access Journals (Sweden)

    Andrew Maltez Thomas

    2016-12-01

    Full Text Available Sporadic and inflammatory forms of colorectal cancer (CRC account for more than 80% of cases. Recent publications have shown mechanistic evidence for the involvement of gut bacteria in the development of both CRC-forms. Whereas colon and rectal cancer have been routinely studied together as CRC, increasing evidence show these to be distinct diseases. Also, the common use of fecal samples to study microbial communities may reflect disease state but possibly not the tumor microenvironment. We performed this study to evaluate differences in bacterial communities found in tissue samples of 18 rectal-cancer subjects when compared to 18 non-cancer controls. Samples were collected during exploratory colonoscopy (non-cancer group or during surgery for tumor excision (rectal-cancer group. High throughput 16S rRNA amplicon sequencing of the V4-V5 region was conducted on the Ion PGM platform, reads were filtered using Qiime and clustered using UPARSE. We observed significant increases in species richness and diversity in rectal cancer samples, evidenced by the total number of OTUs and the Shannon and Simpson indexes. Enterotyping analysis divided our cohort into two groups, with the majority of rectal cancer samples clustering into one enterotype, characterized by a greater abundance of Bacteroides and Dorea. At the phylum level, rectal-cancer samples had increased abundance of candidate phylum OD1 (also known as Parcubacteria whilst non-cancer samples had increased abundance of Planctomycetes. At the genera level, rectal-cancer samples had higher abundances of Bacteroides, Phascolarctobacterium, Parabacteroides, Desulfovibrio and Odoribacter whereas non-cancer samples had higher abundances of Pseudomonas, Escherichia, Acinetobacter, Lactobacillus and Bacillus. Two Bacteroides fragilis OTUs were more abundant among rectal-cancer patients seen through 16S rRNA amplicon sequencing, whose presence was confirmed by immunohistochemistry and enrichment verified

  4. Ceftaroline fosamil: A super-cephalosporin?

    Science.gov (United States)

    Ghamrawi, Riane J; Neuner, Elizabeth; Rehm, Susan J

    2015-07-01

    Ceftaroline is a broad-spectrum cephalosporin used to treat infections caused by a variety of microorganisms, including methicillin-resistant Staphylococcus aureus (MRSA) and multidrug-resistant Streptococcus pneumoniae. However, it is not active against Pseudomonas aeruginosa, Bacteroides fragilis, and carbapenem-resistant Enterobacteriaceae. Its approved indications include community-acquired bacterial pneumonia and bacterial infections of skin and skin structures. It has also been used off-label to treat osteomyelitis, endocarditis, and meningitis caused by ceftaroline-susceptible organisms. Copyright © 2015 Cleveland Clinic.

  5. An ATP Binding Cassette Transporter Mediates the Uptake of α-(1,6)-Linked Dietary Oligosaccharides in Bifidobacterium and Correlates with Competitive Growth on These Substrates

    DEFF Research Database (Denmark)

    Hansen, Morten Ejby; Fredslund, Folmer; Andersen, Joakim Mark

    2016-01-01

    composition with preference for the trisaccharides raffinose and panose. This preference is also reflected in the -(1,6)-galactoside uptake profile of the bacterium. Structures of BlG16BP in complex with raffinose and panose revealed the basis for the remarkable ligand binding plasticity of BlG16BP, which...... of raffinose provides an important competitive advantage, particularly against dominant Bacteroides that lack glycan-specific ABC-transporters. This novel insight highlights the role of glycan transport in defining the metabolic specialization of gut bacteria....

  6. Stable symbiotic nitrogen fixation under water-deficit field conditions by a stress-tolerant alfalfa microsymbiont and its complete genome sequence.

    Science.gov (United States)

    Jozefkowicz, Cintia; Brambilla, Silvina; Frare, Romina; Stritzler, Margarita; Piccinetti, Carlos; Puente, Mariana; Berini, Carolina Andrea; Pérez, Pedro Reyes; Soto, Gabriela; Ayub, Nicolás

    2017-12-10

    We here characterized the stress-tolerant alfalfa microsymbiont Sinorhizobium meliloti B401. B401-treated plants showed high nitrogen fixation rates under humid and semiarid environments. The production of glycine betaine in isolated bacteroids positively correlated with low precipitation levels, suggesting that this compound acts as a critical osmoprotectant under field conditions. Genome analysis revealed that strain B401 contains alternative pathways for the biosynthesis and uptake of glycine betaine and its precursors. Such genomic information will offer substantial insight into the environmental physiology of this biotechnologically valuable nitrogen-fixing bacterium. Copyright © 2017 Elsevier B.V. All rights reserved.

  7. Influence of age and immunization on development of gingivitis in rats

    DEFF Research Database (Denmark)

    Lekic, P; Klausen, B; Friis-Hasché, E

    1989-01-01

    To study the effect of age and antigenic priming on the development of gingivitis, 33 healthy rats were placed in contact with Streptococcus mutans, Actinomyces viscosus, Fusobacterium nucleatum, and Bacteroides gingivalis. On days 0, 3, 7, and 14 after inoculation, the gingival condition...... was judged clinically and histologically, and serum antibody titers against the bacteria were measured. The rats were divided into three groups: 1 month old, 3 months old, and 3 months old immunized. None of the young rats developed gingivitis during the experiment, whereas half of the adult and all...

  8. Efficacy of fecal microbiota transplantation in 2 children with recurrent Clostridium difficile infection and its impact on their growth and gut microbiome.

    Science.gov (United States)

    Walia, Ritu; Garg, Shashank; Song, Yang; Girotra, Mohit; Cuffari, Carmen; Fricke, Wolfgang Florian; Dutta, Sudhir K

    2014-11-01

    Fecal microbiota transplantation (FMT) is recognized as an alternative therapeutic modality for recurrent Clostridium difficile infection (RCDI); however, data on its efficacy in children are lacking, including its effect on their growth and fecal microbiota. We report on 2 young children (<3 years old) who failed available therapeutics for RCDI, but responded remarkably well to FMT. Besides resolution of clinical features of C difficile infection (CDI), FMT administration led to marked improvement in their growth, along with increased microbiota diversity, especially proportion of Bacteroides. Our 2 cases illustrate the efficacy of FMT in children with RCDI and its positive effect on their growth and gut microbiota.

  9. Single-molecule imaging can be achieved in live obligate anaerobic bacteria

    Science.gov (United States)

    Karunatilaka, Krishanthi S.; Coupland, Ben R.; Cameron, Elizabeth A.; Martens, Eric C.; Koropatkin, Nicole K.; Biteen, Julie S.

    2013-02-01

    Single-molecule fluorescence (SMF) permits imaging with nanometer-scale resolution. This technique is particularly useful for cellular imaging as it provides a non-invasive, minimally perturbative means to examine macromolecular localization and dynamics, even in live cells. Here, we demonstrate that nanometer-scale SMF imaging can be extended to a new category of experiments: intracellular imaging of live, obligate anaerobic cells on the benchtop. We investigate the starch-utilization system (Sus) proteins in the gut symbiont Bacteroides thetaiotaomicron and discuss three different labels that we implemented to detect these proteins: fluorescent proteins, the tetracysteine-based FlAsH tag, and the enzymatic HaloTag.

  10. Metagenomic Systems Biology of the Human Microbiome

    DEFF Research Database (Denmark)

    Bonde, Ida

    , nose and oral cavity has been analyzed. The central method has been a co-abundance clustering method, which separates genes from metagenomics data under the assumption that genes originating from the same DNA (e.g. a bacterial genome, a phage or a plasmid) will co-vary across samples. Thus, co...... to previous Blastocystis prevalence studies. Moreover, it was found that individuals with a Bacteroides-driven enterotype were less prone to harbor the Blastocystis parasite. Finally, the CAG clustering method was applied to metagenomics data from the human nose- and oral-cavity. It was concluded...

  11. NADP+ -dependent malic enzyme of Rhizobium meliloti.

    OpenAIRE

    Driscoll, B T; Finan, T M

    1996-01-01

    The bacterium Rhizobium meliloti, which forms N2-fixing root nodules on alfalfa, has two distinct malic enzymes; one is NADP+ dependent, while a second has maximal activity when NAD+ is the coenzyme. The diphosphopyridine nucleotide (NAD+)-dependent malic enzyme (DME) is required for symbiotic N2 fixation, likely as part of a pathway for the conversion of C4-dicarboxylic acids to acetyl coenzyme A in N2-fixing bacteroids. Here, we report the cloning and localization of the tme gene (encoding ...

  12. Microbiome of the pre-epithelial biofilm of the colon of albino rats with experimental thyrotoxicosis

    Directory of Open Access Journals (Sweden)

    L.I. Sydorchuk

    2017-11-01

    Full Text Available Background. The microbiome of the pre-epithelial biofilm of the large intestine in direct contact with the body also interacts with the immune and other systems that emphasizes the urgency of its study in various diseases. The purpose of the study was to determine the taxonomic composition, population level, analytical microecological indicators and the degree of microecological disorders of the pre-epithelial biofilm of the large intestine in albino rats with thyrotoxicosis. Materials and methods. Experiments were carried out on 25 mature male albino rats weighing 220–240 g, of which 15 animals were included to the control group (intact animals, and 10 rats — to the main group. The experimental thyrotoxicosis was simulated by intragastric administration of L-thyroxine for 14 days. Under sterile conditions, a laparotomy was performed, a segment (up to 3 cm of the large intestine with its contents was taken. The washed portion of the intestine was homogenized with a sterile 0.9% NaCl solution. A series of ten-fold dilutions with 10–2 to 10–7 concentrations of the initial mixture were prepared. From each tube, 0.01 ml were seeded on solid optimal nutrient media with subsequent isolation and identification of microbes according to morphological, tinctorial, cultural and biochemical properties. Results. In some animals, bifidobacteria and lactobacilli, as well as bacteroides and escherichia, are eliminated. A significant deficiency of not only bifidobacteria by 48.50 % and lactobacillus by 94.59 %, but also of bacteroides by 44.85 % was established. Determination of the quantitative dominance of each taxon showed that the dominant role of bifidobacteria in the microbiocenosis is reduced by 82.76 %, lactobacillus — by 2.20 times, and the role of bacteroides in the microbiocenosis of the epithelial biofilm of the large intestine of albino rats with the experimental thyrotoxicosis — by 43.04 %, E.coli — by 7.18 %, but the role of

  13. A designated centre for people with disabilities operated by Muiríosa Foundation, Kildare

    LENUS (Irish Health Repository)

    Claesson, Marcus J

    2011-03-15

    Alterations in the human intestinal microbiota are linked to conditions including inflammatory bowel disease, irritable bowel syndrome, and obesity. The microbiota also undergoes substantial changes at the extremes of life, in infants and older people, the ramifications of which are still being explored. We applied pyrosequencing of over 40,000 16S rRNA gene V4 region amplicons per subject to characterize the fecal microbiota in 161 subjects aged 65 y and older and 9 younger control subjects. The microbiota of each individual subject constituted a unique profile that was separable from all others. In 68% of the individuals, the microbiota was dominated by phylum Bacteroides, with an average proportion of 57% across all 161 baseline samples. Phylum Firmicutes had an average proportion of 40%. The proportions of some phyla and genera associated with disease or health also varied dramatically, including Proteobacteria, Actinobacteria, and Faecalibacteria. The core microbiota of elderly subjects was distinct from that previously established for younger adults, with a greater proportion of Bacteroides spp. and distinct abundance patterns of Clostridium groups. Analyses of 26 fecal microbiota datasets from 3-month follow-up samples indicated that in 85% of the subjects, the microbiota composition was more like the corresponding time-0 sample than any other dataset. We conclude that the fecal microbiota of the elderly shows temporal stability over limited time in the majority of subjects but is characterized by unusual phylum proportions and extreme variability.

  14. Microbiota saprófita associada à doença periodontal em cães Oral flora associated with periodontal disease in dogs

    Directory of Open Access Journals (Sweden)

    L.M. Domingues

    1999-08-01

    Full Text Available Realizou-se um estudo sobre a microbiota saprófita associada à doença periodontal espontânea em cães com o objetivo de identificar as bactérias anaeróbias predominantes nas lesões. Com auxílio de cureta odontológica, amostras colhidas diretamente do espaço subgengival foram semeadas em meio CDC (Central for Disease Control para anaeróbios e incubadas, em anaerobiose, a 37°C, por sete dias. A caracterização das colônias foi realizada por meio da morfologia e do teste bioquímico (Sistema API 20AÒ. Identificaram-se os seguintes gêneros: Prevotella spp., Bacteroides spp., Propionibacterium spp., Gemella spp., Actinomyces spp., Eubacterium spp. e Porphyromonas spp.Anaerobic bacteria associated with spontaneous periodontal disorders were studied. The samples were directly colected from the subgingival space with a odontologic curet, and they were plated in Central for Disease Control culture medium for anaerobic bacteria and incubated in anaerobic conditions at 37°C for seven days. The characterization of the colonies were done by the morphologic study and biochemical tests (API 20A. Prevotella spp., Bacteroides spp., Propionibacterium spp., Actinomyces spp., Eubacterium spp., Porphyromonas spp. and Gemella spp. were identified in the samples.

  15. Sacral osteomyelitis after laparoscopic sacral colpopexy performed after a recent dental extraction: a case report.

    Science.gov (United States)

    Apostolis, Costas A; Heiselman, Cassandra

    2014-01-01

    Sacral osteomyelitis and subsequent discitis is a rare complication after laparoscopic sacral colpopexy to repair apical vaginal prolapse. We present a patient who developed Bacteroides fragilis sacral osteomyelitis and discitis after laparoscopic sacrocolpopexy with synthetic monofilament mesh and sacral titanium coil fixation. The patient had undergone dental extraction of 3 infected teeth approximately 2 weeks before sacrocolpopexy for stage IV apical vaginal prolapse. Computed tomography and magnetic resonance imaging (MRI) confirmed sacral osteomyelitis and discitis along with Bacteroides fragilis bacteremia approximately a week and a half after the original surgery. The patient was followed up with serial MRIs of the spine which revealed degeneration at the sacral promontory. The patient underwent successful removal of the entire mesh and sacral titanium coils with resolution of her symptoms. Follow-up MRI of the spine revealed resolution of her sacral osteomyelitis. Sacral osteomyelitis is a rare complication after sacrocolpopexy for pelvic organ prolapse repair. There should be a high index of suspicion for patients presenting with disproportionate low back pain and vague symptoms after surgery. Recent oral surgery may increase the risk of bacteremia and subsequent infectious morbidity after sacrocolpopexy with the use of synthetic mesh for prolapse repair.

  16. A Proteomic Approach of Bradyrhizobium/Aeschynomene Root and Stem Symbioses Reveals the Importance of the fixA Locus for Symbiosis

    Directory of Open Access Journals (Sweden)

    Nathanael Delmotte

    2014-02-01

    Full Text Available Rhizobia are soil bacteria that are able to form symbiosis with plant hosts of the legume family. These associations result in the formation of organs, called nodules in which bacteria fix atmospheric nitrogen to the benefit of the plant. Most of our knowledge on the metabolism and the physiology of the bacteria during symbiosis derives from studying roots nodules of terrestrial plants. Here we used a proteomics approach to investigate the bacterial physiology of photosynthetic Bradyrhizobium sp. ORS278 during the symbiotic process with the semi aquatical plant Aeschynomene indica that forms root and stem nodules. We analyzed the proteomes of bacteria extracted from each type of nodule. First, we analyzed the bacteroid proteome at two different time points and found only minor variation between the bacterial proteomes of 2-week- and 3-week-old nodules. High conservation of the bacteroid proteome was also found when comparing stem nodules and root nodules. Among the stem nodule specific proteins were those related to the phototrophic ability of Bradyrhizobium sp. ORS278. Furthermore, we compared our data with those obtained during an extensive genetic screen previously published. The symbiotic role of four candidate genes which corresponding proteins were found massively produced in the nodules but not identified during this screening was examined. Mutant analysis suggested that in addition to the EtfAB system, the fixA locus is required for symbiotic efficiency.

  17. Assessment of the bacterial diversity of breast milk of healthy women by quantitative real-time PCR.

    Science.gov (United States)

    Collado, M C; Delgado, S; Maldonado, A; Rodríguez, J M

    2009-05-01

    Breast milk has been described as a source of bacteria influencing the development of the infant gut microbiota. Up to the present, few studies have been focused on the application of culture-independent techniques to study bacterial diversity in breast milk. In this context, the aim of this study was to characterize the breast milk microbiota of healthy women by applying the quantitative real-time PCR technique (qRTi-PCR). A total of 50 breast milk samples were analysed by qPCR to assess the presence of different bacterial genera or clusters, including the Bifidobacterium, Lactobacillus, Staphylococcus, Bacteroides, Enterococcus, Streptococcus, Clostridium cluster IV and Clostridium cluster XIVa-XIVb groups. Staphylococcus, Streptococcus, Bifidobacterium and Lactobacillus were the predominant groups and were detected in all the samples. Clostridium XIVa-XIVb and Enterococcus were detected in most of the samples in contrast to the Bacteroides and Clostridium cluster IV groups. Our results confirm the abundance of bacterial DNA in breast milk samples and suggest that the qRTi-PCR technique has a huge potential in the microbiological analysis of human milk. qRTi-PCR allowed the detection of bacterial DNA of streptococci, staphylococci, lactic acid bacteria and bifidobacteria in the samples of human milk, which confirms that breast milk can be an important source of bacteria and bacterial DNA to the infant gut.

  18. Microbial communities in pre-columbian coprolites.

    Directory of Open Access Journals (Sweden)

    Tasha M Santiago-Rodriguez

    Full Text Available The study of coprolites from earlier cultures represents a great opportunity to study an "unaltered" composition of the intestinal microbiota. To test this, pre-Columbian coprolites from two cultures, the Huecoid and Saladoid, were evaluated for the presence of DNA, proteins and lipids by cytochemical staining, human and/or dog-specific Bacteroides spp. by PCR, as well as bacteria, fungi and archaea using Terminal Restriction Fragment analyses. DNA, proteins and lipids, and human-specific Bacteroides DNA were detected in all coprolites. Multidimensional scaling analyses resulted in spatial arrangements of microbial profiles by culture, further supported by cluster analysis and ANOSIM. Differences between the microbial communities were positively correlated with culture, and SIMPER analysis indicated 68.8% dissimilarity between the Huecoid and Saladoid. Proteobacteria, Bacteroidetes and methanogens were found in all coprolite samples. Propionebacteria, Shewanella and lactic acid bacteria dominated in the Huecoid samples, while Acidobacteria, and peptococci were dominant in Saladoid samples. Yeasts, including Candida albicans and Crypotococcus spp. were found in all samples. Basidiomycetes were the most notable fungi in Huecoid samples while Ascomycetes predominated in Saladoid samples, suggesting differences in dietary habits. Our study provides an approach for the study of the microbial communities of coprolite samples from various cultures.

  19. New Iron Acquisition System in Bacteroidetes

    Science.gov (United States)

    Manfredi, Pablo; Lauber, Frédéric; Renzi, Francesco; Hack, Katrin; Hess, Estelle

    2014-01-01

    Capnocytophaga canimorsus, a dog mouth commensal and a member of the Bacteroidetes phylum, causes rare but often fatal septicemia in humans that have been in contact with a dog. Here, we show that C. canimorsus strains isolated from human infections grow readily in heat-inactivated human serum and that this property depends on a typical polysaccharide utilization locus (PUL), namely, PUL3 in strain Cc5. PUL are a hallmark of Bacteroidetes, and they encode various products, including surface protein complexes that capture and process polysaccharides or glycoproteins. The archetype system is the Bacteroides thetaiotaomicron Sus system, devoted to starch utilization. Unexpectedly, PUL3 conferred the capacity to acquire iron from serotransferrin (STF), and this capacity required each of the seven encoded proteins, indicating that a whole Sus-like machinery is acting as an iron capture system (ICS), a new and unexpected function for Sus-like machinery. No siderophore could be detected in the culture supernatant of C. canimorsus, suggesting that the Sus-like machinery captures iron directly from transferrin, but this could not be formally demonstrated. The seven genes of the ICS were found in the genomes of several opportunistic pathogens from the Capnocytophaga and Prevotella genera, in different isolates of the severe poultry pathogen Riemerella anatipestifer, and in strains of Bacteroides fragilis and Odoribacter splanchnicus isolated from human infections. Thus, this study describes a new type of ICS that evolved in Bacteroidetes from a polysaccharide utilization system and most likely represents an important virulence factor in this group. PMID:25368114

  20. The association of type II diabetes with gut microbiota composition.

    Science.gov (United States)

    Navab-Moghadam, Fatemeh; Sedighi, Mansour; Khamseh, Mohammad E; Alaei-Shahmiri, Fariba; Talebi, Malihe; Razavi, Shabnam; Amirmozafari, Nour

    2017-09-01

    It is known that type 2 diabetes (T2D) in humans could be linked to the composition of gut microbiota. The aim of this study was to evaluate three faecal bacterial species, including Bacteroides fragilis, Bifidobacterium longum and Faecalibacterium prausnitzii in patients with T2D. This case control study included 18 patients with T2D and 18 matched persons without diabetes. The concentrations of B. fragilis, B. longum and F. prausnitzii were determined by quantitative Real-Time PCR. Quantitative PCR analysis revealed that the gut bacterial composition in patients with T2D was partially different from that in the healthy individuals. Faecalibacterium prausnitzii was significantly lower in patients with T2D (P-value = 0.038). Bacteroides fragilis was under-represented in the microbiota of the group with diabetes, but its difference between two groups was not significant (P-value = 0.38). No difference was observed for B. longum community between the both groups (P-value = 0.99). Characterization of specific species of intestinal microbiota shows some compositional changes in patients with T2D. The results may be valuable for developing strategies to control type 2 diabetes by modifying the intestinal microbiota. Long-term studies with emphasis on other bacterial groups are suggested to clarify the association of T2D with gut microbiota. Copyright © 2017 Elsevier Ltd. All rights reserved.

  1. Gut microbiota composition modifies fecal metabolic profiles in mice.

    Science.gov (United States)

    Zhao, Ying; Wu, Junfang; Li, Jia V; Zhou, Ning-Yi; Tang, Huiru; Wang, Yulan

    2013-06-07

    The gut microbiome is known to be extensively involved in human health and disease. In order to reveal the metabolic relationship between host and microbiome, we monitored recovery of the gut microbiota composition and fecal profiles of mice after gentamicin and/or ceftriaxone treatments. This was performed by employing (1)H nuclear magnetic resonance (NMR)-based metabonomics and denaturing gradient gel electrophoresis (DGGE) fingerprint of gut microbiota. The common features of fecal metabolites postantibiotic treatment include decreased levels of short chain fatty acids (SCFAs), amino acids and primary bile acids and increased oligosaccharides, d-pinitol, choline and secondary bile acids (deoxycholic acid). This suggests suppressed bacterial fermentation, protein degradation and enhanced gut microbial modification of bile acids. Barnesiella, Prevotella, and Alistipes levels were shown to decrease as a result of the antibiotic treatment, whereas levels of Bacteroides, Enterococcus and Erysipelotrichaceae incertae sedis, and Mycoplasma increased after gentamicin and ceftriaxone treatment. In addition, there was a strong correlation between fecal profiles and levels of Bacteroides, Barnesiella, Alistipes and Prevotella. The integration of metabonomics and gut microbiota profiling provides important information on the changes of gut microbiota and their impact on fecal profiles during the recovery after antibiotic treatment. The correlation between gut microbiota and fecal metabolites provides important information on the function of bacteria, which in turn could be important in optimizing therapeutic strategies, and developing potential microbiota-based disease preventions and therapeutic interventions.

  2. Composition of gut microbiota in obese and normal-weight Mexican school-age children and its association with metabolic traits.

    Science.gov (United States)

    López-Contreras, B E; Morán-Ramos, S; Villarruel-Vázquez, R; Macías-Kauffer, L; Villamil-Ramírez, H; León-Mimila, P; Vega-Badillo, J; Sánchez-Muñoz, F; Llanos-Moreno, L E; Canizalez-Román, A; Del Río-Navarro, B; Ibarra-González, I; Vela-Amieva, M; Villarreal-Molina, T; Ochoa-Leyva, A; Aguilar-Salinas, C A; Canizales-Quinteros, S

    2017-12-05

    Childhood obesity is a serious public health problem in Mexico. Adult gut microbiota composition has been linked to obesity, but few studies have addressed the role of gut microbiota in childhood obesity. The aim of this study is to compare gut microbiota composition in obese and normal-weight children and to associate gut microbiota profiles with amino acid serum levels and obesity-related metabolic traits. Microbial taxa relative abundance was determined by 16S rRNA sequencing in 67 normal-weight and 71 obese children aged 6-12 years. Serum amino acid levels were measured by mass spectrometry. Associations between microbiota composition, metabolic parameters and amino acid serum levels were tested. No significant differences in phyla abundances or Firmicutes/Bacteroidetes ratios were observed between normal-weight and obese children. However, Bacteroides eggerthii abundance was significantly higher in obese children and correlated positively with body fat percentage and negatively with insoluble fibre intake. Additionally, Bacteroides plebeius and unclassified Christensenellaceae abundances were significantly higher in normal-weight children. Abundance of both these species correlated negatively with phenylalanine serum levels, a metabolite also found to be associated with obesity in Mexican children. The study identified bacterial species associated with obesity, metabolic complications and amino acid serum levels in Mexican children. © 2017 World Obesity Federation.

  3. In vitro characterisation of the fermentation profile and prebiotic capacity of gold-fleshed kiwifruit.

    Science.gov (United States)

    Blatchford, P; Bentley-Hewitt, K L; Stoklosinski, H; McGhie, T; Gearry, R; Gibson, G; Ansell, J

    2015-01-01

    A new Actinidia chinensis gold-fleshed kiwifruit cultivar 'Zesy002' was tested to investigate whether it could positively modulate the composition of the human colonic microbiota. Digested Zesy002 kiwifruit was added to in vitro pH-controlled anaerobic batch fermenters that were inoculated with representative human faecal microbiota. Alterations to the gut microbial ecology were determined by 16S rRNA gene sequencing and metabolic end products were measured using gas chromatography and liquid chromatography - mass spectrometry. Results indicated a substantial shift in the composition of bacteria within the gut models caused by kiwifruit supplementation. Zesy002 supplemented microbiota had a significantly higher abundance of Bacteroides spp., Parabacteroides spp. and Bifidobacterium spp. after 48 h of fermentation compared with the start of the fermentation. Organic acids from kiwifruit were able to endure simulated gastrointestinal digestion and were detectable in the first 10 h of fermentation. The fermentable carbohydrates were converted to beneficial organic acids with a particular predilection for propionate production, corresponding with the rise in Bacteroides spp. and Parabacteroides spp. These results support the claim that Zesy002 kiwifruit non-digestible fractions can effect favourable changes to the human colonic microbial community and primary metabolites, and demonstrate a hitherto unknown effect of Zesy002 on colonic microbiota under in vitro conditions.

  4. Association of dietary type with fecal microbiota in vegetarians and omnivores in Slovenia.

    Science.gov (United States)

    Matijašić, Bojana Bogovič; Obermajer, Tanja; Lipoglavšek, Luka; Grabnar, Iztok; Avguštin, Gorazd; Rogelj, Irena

    2014-06-01

    The purpose of this study was to discover differences in the human fecal microbiota composition driven by long-term omnivore versus vegan/lacto-vegetarian dietary pattern. In addition, the possible association of demographic characteristics and dietary habits such as consumption of particular foods with the fecal microbiota was examined. This study was conducted on a Slovenian population comprising 31 vegetarian participants (11 lacto-vegetarians and 20 vegans) and 29 omnivore participants. Bacterial DNA was extracted from the frozen fecal samples by Maxwell 16 Tissue DNA Purification Kit (Promega). Relative quantification of selected bacterial groups was performed by real-time PCR. Differences in fecal microbiota composition were evaluated by PCR-DGGE fingerprinting of the V3 16S rRNA region. Participants' demographic characteristics, dietary habits and health status information were collected through a questionnaire. Vegetarian diet was associated with higher ratio (% of group-specific DNA in relation to all bacterial DNA) of Bacteroides-Prevotella, Bacteroides thetaiotaomicron, Clostridium clostridioforme and Faecalibacterium prausnitzii, but with lower ratio (%) of Clostridium cluster XIVa. Real-time PCR also showed a higher concentration and ratio of Enterobacteriaceae (16S rDNA copies/g and %) in female participants (p yoghurt, other dairy products, fish and seafood) and vegetarian type of diet explained the largest share of variance in microbial community structure. Fecal microbiota composition was also associated with participants' age, gender and body mass.

  5. High rate of non-susceptibility to metronidazole and clindamycin in anaerobic isolates: Data from a clinical laboratory from Karachi, Pakistan.

    Science.gov (United States)

    Sheikh, Sadia Omer; Jabeen, Kauser; Qaiser, Saba; Ahsan, Syed Tanwir; Khan, Erum; Zafar, Afia

    2015-06-01

    Due to increasing resistance amongst anaerobic pathogens periodic surveillance of resistance has been recommended in regional/local settings. Anaerobic antimicrobial susceptibility testing is not routinely performed in many laboratories in Pakistan, hence absence of local data may lead to inappropriate empirical therapy in serious cases. 121 clinically significant anaerobic strains (26/121; 21% bacteremic isolates) were isolated and saved from 2010 to 2011. Susceptibility testing against metronidazole, clindamycin, co-amoxiclav, meropenem, piperacillin/tazobactam, linezolid and gatifloxacin was performed by determining minimum inhibitory concentrations (MICs). A high proportion of non-susceptible strains to metronidazole (10% of 121 isolates) and clindamycin (12% of 121 isolates) was seen, most noticeable in Bacteroides fragilis. Three Bacteroides species strains were non-susceptible to both metronidazole and clindamycin. One strain of Clostridium species was fully resistant to metronidazole and had intermediate resistance to clindamycin. No resistance to any of the other tested antibiotics was seen. Resistance to metronidazole was higher in bacteremic vs. non bacteremic isolates (p = value 0.07). In our setting where there is a high usage of empirical metronidazole and clindamycin for the treatment of serious anaerobic infections clinicians should be aware of increased resistance to these agents. Periodic surveillance of resistance to anti-anaerobic drugs especially metronidazole and clindamycin should be performed to generate antibiogram and guide appropriate empiric therapy. Copyright © 2015 Elsevier Ltd. All rights reserved.

  6. Evaluation of the routine antimicrobial susceptibility testing results of clinically significant anaerobic bacteria in a Slovenian tertiary-care hospital in 2015.

    Science.gov (United States)

    Jeverica, Samo; Kolenc, Urša; Mueller-Premru, Manica; Papst, Lea

    2017-10-01

    The aim of our study was to determined antimicrobial susceptibility profiles of 2673 clinically significant anaerobic bacteria belonging to the major genera, isolated in 2015 in a large tertiary-care hospital in Slovenia. The species identification was performed by MALDI-TOF mass spectrometry. Antimicrobial susceptibility was determined immediately at the isolation of the strains against: penicillin, co-amoxiclav, imipenem, clindamycin and metronidazole, using gradient diffusion methodology and EUCAST breakpoints. The most frequent anaerobes were Bacteroides fragilis group with 31% (n = 817), Gram positive anaerobic cocci (GPACs) with 22% (n = 589), Prevotella with 14% (n = 313) and Propionibacterium with 8% (n = 225). Metronidazole has retained full activity (100%) against all groups of anaerobic bacteria intrinsically susceptible to it. Co-amoxiclav and imipenem were active against most tested anaerobes with zero or low resistance rates. However, observed resistance to co-amoxiclav (8%) and imipenem (1%) is worrying especially among B. fragilis group isolates. High overall resistance (23%) to clindamycin was detected in our study and was highest among the genera Prevotella, Bacteroides, Parabacteroides, GPACs and Clostridium. Routine testing of antimicrobial susceptibility of clinically relevant anaerobic bacteria is feasible and provides good surveillance data. Copyright © 2017 The Authors. Published by Elsevier Ltd.. All rights reserved.

  7. An in Vitro Experimental Study on the Antimicrobial Activity of Silicone Oil against Anaerobic Bacteria.

    Science.gov (United States)

    Arici, Ceyhun; Aras, Cengiz; Tokman, Hrisi Bahar; Torun, Muzeyyen Mamal

    2016-01-01

    To investigate the in vitro antimicrobial activity of silicone oil against anaerobic agents, specifically Propionibacterium acnes, Peptostreptococcus spp., Peptostreptococcus anaerobius, Bacteroides fragilis, Fuobacterium spp., and Clostridium tertium. A 0.5 McFarland turbidity of Propionibacterium acnes, Peptostreptococcus spp., Peptostreptococcus anaerobius, Bacteroides fragilis, Fuobacterium spp., and Clostridium tertium was prepared, and 0.1 mL was inoculated into 0.9 mL of silicone oil. Control inoculations were performed in anaerobic blood agar and fluid thioglycollate medium without silicone oil. Propionibacterium acnes retained their viability on the 3rd day in the presence of silicone oil. In total, 9.7 × 10(6) colonies were enumerated from 1 mL of silicone oil. After a prolonged incubation of 7 days, the number of colonies observed was 9.2 × 10(6). The other bacteria disappeared after the 3rd day of incubation in silicone oil. Propionibacterium acnes, which is the most common chronic postoperative endophthalmitis agent, is thought to be resistant to silicone oil.

  8. Antibiotic susceptibility profiles of anaerobic pathogens in The Netherlands.

    Science.gov (United States)

    Veloo, A C M; van Winkelhoff, A J

    2015-02-01

    The antibiotic susceptibility profile of the Bacteroides fragilis group, Gram-positive anaerobic cocci (GPAC), Fusobacterium spp., Prevotella spp., Veillonella spp. and Bilophila wadsworthia for amoxicillin, amoxicillin-clavulanic acid, clindamycin and metronidazole was determined. Human clinical isolates were isolated between 2011 and 2013 at the Microbiological Diagnostic Laboratory of the University Medical Center Groningen, The Netherlands and subjected to MALDI-TOF MS identification and susceptibility testing using E-test for MIC determination. Differences in clindamycin susceptibility between species of the B. fragilis group and GPAC were observed, with Bacteroides ovatus and Peptoniphilus harei having the highest resistance rates. Compared to other European countries, in The Netherlands the MIC90 for clindamycin of fusobacteria is low. Metronidazole resistance was first encountered in the genus Prevotella in 2013, but not in species of GPAC as reported in Belgium and Bulgaria. The differences in clindamycin resistance between the different European countries and reports of metronidazole resistance within the genera Prevotella and GPAC warrant more extensive susceptibility studies on anaerobic pathogens. Copyright © 2014 Elsevier Ltd. All rights reserved.

  9. Comparative cytotoxicity of periodontal bacteria

    International Nuclear Information System (INIS)

    Stevens, R.H.; Hammond, B.F.

    1988-01-01

    The direct cytotoxicity of sonic extracts (SE) from nine periodontal bacteria for human gingival fibroblasts (HGF) was compared. Equivalent dosages (in terms of protein concentration) of SE were used to challenge HGF cultures. The cytotoxic potential of each SE was assessed by its ability to (1) inhibit HGF proliferation, as measured by direct cell counts; (2) inhibit 3H-thymidine incorporation in HGF cultures; or (3) cause morphological alterations of the cells in challenged cultures. The highest concentration (500 micrograms SE protein/ml) of any of the SEs used to challenge the cells was found to be markedly inhibitory to the HGFs by all three of the criteria of cytotoxicity. At the lowest dosage tested (50 micrograms SE protein/ml); only SE from Actinobacillus actinomycetemcomitans, Bacteroides gingivalis, and Fusobacterium nucleatum caused a significant effect (greater than 90% inhibition or overt morphological abnormalities) in the HGFs as determined by any of the criteria employed. SE from Capnocytophaga sputigena, Eikenella corrodens, or Wolinella recta also inhibited cell proliferation and thymidine incorporation at this dosage; however, the degree of inhibition (5-50%) was consistently, clearly less than that of the first group of three organisms named above. The SE of the three other organisms tested (Actinomyces odontolyticus, Bacteroides intermedius, and Streptococcus sanguis) had little or no effect (0-10% inhibition) at this concentration. The data suggest that the outcome of the interaction between bacterial components and normal resident cells of the periodontium is, at least in part, a function of the bacterial species

  10. Morphogenesis of root nodules in white clover. II. The effect of mutation in genes nod IJ of the microsymbiont upon the nodule structure

    Directory of Open Access Journals (Sweden)

    Barbara Łotocka

    2014-01-01

    Full Text Available Morphogenesis of ineffective root nodules initiated on the roots of white clover 'Astra' by the Rhizobium leguminosarum biovar. trifolii strains ANU261 (Tn5 insertion in nod 1 gene and ANU262 (Tn5 insertion in nod J gene was investigated. Following changes were observed, as compared to the wild-type nodulation: the exaggerated, not delayed reaction of root hairs; the delay in nodulation with the number of nodules the same as in plants inoculated with a wild strain; the formation and organization of the nodule primordium not changed in comparison with the wild-type nodules; infection threads abnormally branched and diffusing with bacteria deprived of light zone and enriched with storage material; infected cells of bacteroidal tissue abnormally strongly osmiophilic and only slightly vacuolated; symbiosomes with very narrowed peribacteroidal space, subject to premature degradation; abnormal accumulation of starch in the nodule tissues; nodule development blocked at the stage of laterally situated meristem and single nodule bundle; inhibition of divisions in the meristem and vacuolation of its cells; the appearance of single cells with colonies of saprophytic rhizobia embedded in the fibrillar matrix in the old, degraded regions of the bacteroidal tissue.

  11. Assessment of Fecal Microflora Changes in Pigs Supplemented with Herbal Residue and Prebiotic.

    Directory of Open Access Journals (Sweden)

    Ashis Kumar Samanta

    Full Text Available Antibiotic usage in animals as a growth promoter is considered as public health issue due to its negative impact on consumer health and environment. The present study aimed to evaluate effectiveness of herbal residue (ginger, Zingiber officinale, dried rhizome powder and prebiotic (inulin as an alternative to antibiotics by comparing fecal microflora composition using terminal restriction fragment length polymorphism. The grower pigs were offered feed containing antibiotic (tetracycline, ginger and inulin separately and un-supplemented group served as control. The study revealed significant changes in the microbial abundance based on operational taxonomic units (OTUs among the groups. Presumptive identification of organisms was established based on the fragment length of OTUs generated with three restriction enzymes (MspI, Sau3AI and BsuRI. The abundance of OTUs representing Bacteroides intestinalis, Eubacterium oxidoreducens, Selonomonas sp., Methylobacterium sp. and Denitrobacter sp. was found significantly greater in inulin supplemented pigs. Similarly, the abundance of OTUs representing Bacteroides intestinalis, Selonomonas sp., and Phascolarcobacterium faecium was found significantly greater in ginger supplemented pigs. In contrast, the abundance of OTUs representing pathogenic microorganisms Atopostipes suicloacalis and Bartonella quintana str. Toulouse was significantly reduced in ginger and inulin supplemented pigs. The OTUs were found to be clustered under two major phylotypes; ginger-inulin and control-tetracycline. Additionally, the abundance of OTUs was similar in ginger and inulin supplemented pigs. The results suggest the potential of ginger and prebioticsto replace antibiotics in the diet of grower pig.

  12. Microgravity effects on the legume/Rhizobium symbiosis

    Science.gov (United States)

    Urban, James E.

    1997-01-01

    Symbiotic nitrogen fixation is of critical importance to world agriculture and likely will be a critical part of life support systems developed for prolonged missions in space. Bacteroid formation, an essential step in an effective Dutch White Clover/Rhizobium leguminosarum bv trifolii symbiosis, is induced by succinic acid which is produced by the plant and which is bound and incorporated by the bacterium. Aspirin mimics succinate in its role as a bacteroid inducer and measures of aspirin binding mimiced measurements of succinate binding. In normal gravity (1×g), rhizobium bacteria immediately bound relatively high levels of aspirin (or succinate) in a readily reversible manner. Within a few seconds a portion of this initially bound aspirin became irreversibly bound. In the microgravity environment aboard the NASA 930 aircraft, rhizobia did not display the initial reversible binding of succinate, but did display a similar kinetic pattern of irreversible binding, and ultimately bound 32% more succinate (Acta Astronautica 36:129-133, 1995.) In normal gravity succinate treated cells stop dividing and swell to their maximum size (twice the normal cell volume) within a time equivalent to the time required for two normal cell doublings. Swelling in microgravity was tested in FPA and BPM sample holders aboard the space shuttle (USML-1, and STS-54, 57, and 60.) The behavior of cells in the two sample holders was similar, and swelling behavior of cells in microgravity was identical to behavior in normal gravity.

  13. Fate of antibiotic resistance genes and class 1 integrons in soil microcosms following the application of treated residual municipal wastewater solids.

    Science.gov (United States)

    Burch, Tucker R; Sadowsky, Michael J; LaPara, Timothy M

    2014-05-20

    Substantial quantities of antibiotic resistance genes (ARGs) are discharged with treated residual municipal wastewater solids and subsequently applied to soil. The objective of this work was to determine the decay rates for ARGs and class 1 integrons following simulated land application of treated wastewater solids. Treated residual solids from two full-scale treatment plants were applied to sets of triplicate soil microcosms in two independent experiments. Experiment 1 investigated loading rates of 20, 40, and 100 g kg(-1) of residual solids to a sandy soil, while experiment 2 investigated a loading rate of 40 g kg(-1) to a silty-loamy soil. Five ARGs (erm(B), sul1, tet(A), tet(W), and tet(X)), the integrase of class 1 integrons (intI1), 16S rRNA genes, 16S rRNA genes of all Bacteroides spp., and 16S rRNA genes of human-specific Bacteroides spp. were quantified using real-time polymerase chain reaction. ARGs and intI1 quantities declined in most microcosms, with statistically significant (P rates were much slower than have been previously reported for unit operations used to treat wastewater solids (e.g., anaerobic digestion). This research suggests that the design and operation of municipal wastewater treatment facilities with the explicit goal of mitigating the release of ARGs should focus on using technologies within the treatment facility, rather than depending on attenuation subsequent to land application.

  14. Distribution of genetic markers of fecal pollution on a freshwater sandy shoreline in proximity to wastewater effluent.

    Science.gov (United States)

    Eichmiller, Jessica J; Hicks, Randall E; Sadowsky, Michael J

    2013-04-02

    Water, sand, and sediment from a Lake Superior harbor site continuously receiving wastewater effluent was sampled monthly for June to October 2010 and from May to September 2011. Understanding the dynamics of genetic markers of fecal bacteria in these matrices is essential to accurately characterizing health risks. Genetic markers for enterococci, total Bacteroides, and human-associated Bacteroides were measured in site-water, sand, and sediment and in final effluent by quantitative PCR. The similarity between the quantity of molecular markers in the water column and effluent indicated that the abundance of genetic markers in the water column was likely controlled by effluent inputs. Effluent turbidity was positively correlated (p ≤ 0.05) with AllBac and HF183 in final effluent and AllBac in the water column. In sand and sediment, Entero1 and AllBac were most abundant in the upper 1-3 cm depths, whereas HF183 was most abundant in the upper 1 cm of sand and at 7 cm in sediment. The AllBac and Entero1 markers were 1- and 2-orders of magnitude more abundant in sand and sediment relative to the water column per unit mass. These results indicate that sand and sediment may act as reservoirs for genetic markers of fecal pollution at some freshwater sites.

  15. One-year calorie restriction impacts gut microbial composition but not its metabolic performance in obese adolescents.

    Science.gov (United States)

    Ruiz, Alicia; Cerdó, Tomás; Jáuregui, Ruy; Pieper, Dietmar H; Marcos, Ascensión; Clemente, Alfonso; García, Federico; Margolles, Abelardo; Ferrer, Manuel; Campoy, Cristina; Suárez, Antonio

    2017-04-01

    Recent evidence has disclosed a connection between gut microbial glycosidase activity and adiposity in obese. Here, we measured microbial α-glucosidase and β-galactosidase activities and sorted fluorescently labeled β-galactosidase containing (βGAL) microorganisms in faecal samples of eight lean and thirteen obese adolescents that followed a controlled calorie restriction program during one year. β-galactosidase is a highly distributed functional trait, mainly expressed by members of Blautia, Bacteroides, Alcaligenes, Acinetobacter and Propionibacterium. Only long-term calorie restriction induced clear changes in the microbiota of obese adolescents. Long-term calorie restriction induced significant shifts in total and βGAL gut microbiota, reducing the Firmicutes:Bacteroidetes ratio and enhancing the growth of beneficial microorganisms such as Bacteroides, Roseburia, Faecalibacterium and Clostridium XIVa. Moreover, the structure and composition of βGAL community in obese after long-term calorie restriction was highly similar to that of lean adolescents. However, despite this high compositional similarity, microbial metabolic performance was different, split in two metabolic states at a body mass index value of 25. Our study shows that calorie restriction is a strong environmental force reshaping gut microbiota though its metabolic performance is linked to host's adiposity, suggesting that functional redundancy and metabolic plasticity are fundamental properties of gut microbial ecosystem. © 2017 Society for Applied Microbiology and John Wiley & Sons Ltd.

  16. Comparison of the intestinal mucosal microbiota in dogs diagnosed with idiopathic inflammatory bowel disease and dogs with food-responsive diarrhea before and after treatment.

    Science.gov (United States)

    Kalenyak, Katja; Isaiah, Anitha; Heilmann, Romy M; Suchodolski, Jan S; Burgener, Iwan A

    2018-02-01

    We report the first study to evaluate the intestinal mucosal microbiota of dogs with inflammatory bowel disease (IBD) and dogs with food-responsive diarrhea (FRD) before and after treatment. It was hypothesized that differences in the microbial composition exist between both disease groups and within groups pre- vs. post-treatment. Duodenal and colonic biopsies were obtained endoscopically from 24 dogs (15 FRD, 9 IBD) before and after treatment. The intestinal microbiota was evaluated by Illumina sequencing of the bacterial 16S rRNA gene. The global bacterial composition did not differ between IBD and FRD dogs, nor between treatment status. However, several bacterial taxa showed a difference in abundance. Comparing disease groups, an unclassified genus of Neisseriaceae was abundant in the duodenum in the IBD group, whereas Bilophila occurred more frequently in the duodenum and Burkholderia in the colon of FRD dogs. Comparing the microbiota pre- and post-treatment revealed Enterococcus, Corynebacterium and Proteobacteria to be enriched in the duodenum of FRD dogs pre-treatment, while Bacteroides was abundant in the colon post-treatment. In dogs with IBD, Bacteroides also reached significant abundance in the colon post-treatment. In conclusion, some differences in individual bacterial taxa were identified between IBD and FRD dogs and between treatment status. © FEMS 2017. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  17. Changes in human fecal microbiota due to chemotherapy analyzed by TaqMan-PCR, 454 sequencing and PCR-DGGE fingerprinting.

    Directory of Open Access Journals (Sweden)

    Jutta Zwielehner

    Full Text Available BACKGROUND: We investigated whether chemotherapy with the presence or absence of antibiotics against different kinds of cancer changed the gastrointestinal microbiota. METHODOLOGY/PRINCIPAL FINDINGS: Feces of 17 ambulant patients receiving chemotherapy with or without concomitant antibiotics were analyzed before and after the chemotherapy cycle at four time points in comparison to 17 gender-, age- and lifestyle-matched healthy controls. We targeted 16S rRNA genes of all bacteria, Bacteroides, bifidobacteria, Clostridium cluster IV and XIVa as well as C. difficile with TaqMan qPCR, denaturing gradient gel electrophoresis (DGGE fingerprinting and high-throughput sequencing. After a significant drop in the abundance of microbiota (p = 0.037 following a single treatment the microbiota recovered within a few days. The chemotherapeutical treatment marginally affected the Bacteroides while the Clostridium cluster IV and XIVa were significantly more sensitive to chemotherapy and antibiotic treatment. DGGE fingerprinting showed decreased diversity of Clostridium cluster IV and XIVa in response to chemotherapy with cluster IV diversity being particularly affected by antibiotics. The occurrence of C. difficile in three out of seventeen subjects was accompanied by a decrease in the genera Bifidobacterium, Lactobacillus, Veillonella and Faecalibacterium prausnitzii. Enterococcus faecium increased following chemotherapy. CONCLUSIONS/SIGNIFICANCE: Despite high individual variations, these results suggest that the observed changes in the human gut microbiota may favor colonization with C. difficile and Enterococcus faecium. Perturbed microbiota may be a target for specific mitigation with safe pre- and probiotics.

  18. A novel transcriptional regulator of L-arabinose utilization in human gut bacteria

    Energy Technology Data Exchange (ETDEWEB)

    Chang, Changsoo; Tesar, Christine; Li, Xiaoqing; Kim, Youngchang; Rodionov, Dmitry A.; Joachimiak, Andrzej

    2015-10-04

    Carbohydrate metabolism plays a crucial role in the ecophysiology of human gut microbiota. Mechanisms of transcriptional regulation of sugar catabolism in commensal and prevalent human gut bacteria such as Bacteroides thetaiotaomicron remain mostly unknown. By a combination of bioinformatics and experimental approaches, we have identified an NrtR family transcription factor (BT0354 in B. thetaiotaomicron, BtAraR) as a novel regulator controlling the arabinose utilization genes. L-arabinose was confirmed to be a negative effector of BtAraR. We have solved the crystal structures of the apo and L-arabinose-bound BtAraR proteins, as well as the complex of apo-protein with a specific DNA operator. BtAraR forms a homodimer with each subunit comprised of the ligand-binding Nudix hydrolase-like domain and the DNA-binding winged-helix-turn-helix (wHTH) domain. We have identified the residues involved in binding of L-arabinose and recognition of DNA. The majority of these residues are well conserved in the AraR orthologs in Bacteroidetes. In the structure of the BtAraR-DNA complex, we found the unique interaction of arginine intercalating its guanidinum moiety into the base pair stacking of B-DNA. L-arabinose binding induces movement of wHTH domains, resulting in a conformation unsuitable for DNA binding. Our analysis facilitates reconstruction of the metabolic and regulatory networks involved in carbohydrate utilization in human gut Bacteroides.

  19. Composition, variability, and temporal stability of the intestinal microbiota of the elderly.

    LENUS (Irish Health Repository)

    Claesson, Marcus J

    2011-03-15

    Alterations in the human intestinal microbiota are linked to conditions including inflammatory bowel disease, irritable bowel syndrome, and obesity. The microbiota also undergoes substantial changes at the extremes of life, in infants and older people, the ramifications of which are still being explored. We applied pyrosequencing of over 40,000 16S rRNA gene V4 region amplicons per subject to characterize the fecal microbiota in 161 subjects aged 65 y and older and 9 younger control subjects. The microbiota of each individual subject constituted a unique profile that was separable from all others. In 68% of the individuals, the microbiota was dominated by phylum Bacteroides, with an average proportion of 57% across all 161 baseline samples. Phylum Firmicutes had an average proportion of 40%. The proportions of some phyla and genera associated with disease or health also varied dramatically, including Proteobacteria, Actinobacteria, and Faecalibacteria. The core microbiota of elderly subjects was distinct from that previously established for younger adults, with a greater proportion of Bacteroides spp. and distinct abundance patterns of Clostridium groups. Analyses of 26 fecal microbiota datasets from 3-month follow-up samples indicated that in 85% of the subjects, the microbiota composition was more like the corresponding time-0 sample than any other dataset. We conclude that the fecal microbiota of the elderly shows temporal stability over limited time in the majority of subjects but is characterized by unusual phylum proportions and extreme variability.

  20. Rhizobium leguminosarum bv. viciae 3841 Adapts to 2,4-Dichlorophenoxyacetic Acid with "Auxin-Like" Morphological Changes, Cell Envelope Remodeling and Upregulation of Central Metabolic Pathways.

    Directory of Open Access Journals (Sweden)

    Supriya V Bhat

    Full Text Available There is a growing need to characterize the effects of environmental stressors at the molecular level on model organisms with the ever increasing number and variety of anthropogenic chemical pollutants. The herbicide 2,4-dichlorophenoxyacetic acid (2,4-D, as one of the most widely applied pesticides in the world, is one such example. This herbicide is known to have non-targeted undesirable effects on humans, animals and soil microbes, but specific molecular targets at sublethal levels are unknown. In this study, we have used Rhizobium leguminosarum bv. viciae 3841 (Rlv as a nitrogen fixing, beneficial model soil organism to characterize the effects of 2,4-D. Using metabolomics and advanced microscopy we determined specific target pathways in the Rlv metabolic network and consequent changes to its phenotype, surface ultrastructure, and physical properties during sublethal 2,4-D exposure. Auxin and 2,4-D, its structural analogue, showed common morphological changes in vitro which were similar to bacteroids isolated from plant nodules, implying that these changes are related to bacteroid differentiation required for nitrogen fixation. Rlv showed remarkable adaptation capabilities in response to the herbicide, with changes to integral pathways of cellular metabolism and the potential to assimilate 2,4-D with consequent changes to its physical and structural properties. This study identifies biomarkers of 2,4-D in Rlv and offers valuable insights into the mode-of-action of 2,4-D in soil bacteria.

  1. Effect of Dietary Protein Levels on Composition of Odorous Compounds and Bacterial Ecology in Pig Manure

    Directory of Open Access Journals (Sweden)

    Sungback Cho

    2015-09-01

    Full Text Available This study was performed to investigate the effect of different levels of dietary crude protein (CP on composition of odorous compounds and bacterial communities in pig manure. A total of 48 male pigs (average initial body weight 45 kg fed diets containing three levels of dietary CP (20%, 17.5%, and 15% and their slurry samples were collected from the pits under the floor every week for one month. Changes in composition of odorous compounds and bacterial communities were analyzed by gas chromatography and 454 FLX titanium pyrosequencing systems, respectively. Levels of phenols, indoles, short chain fatty acid and branched chain fatty acid were lowest (p<0.05 in CP 15% group among three CP levels. Relative abundance of Bacteroidetes phylum and bacterial genera including Leuconostoc, Bacillus, Atopostipes, Peptonphilus, Ruminococcaceae_uc, Bacteroides, and Pseudomonas was lower (p<0.05 in CP 15% than in CP 20% group. There was a positive correlation (p<0.05 between odorous compounds and bacterial genera: phenol, indole, iso-butyric acid, and iso-valeric acid with Atopostipes, p-cresol and skatole with Bacteroides, acetic acid and butyric acid with AM982595_g of Porphyromonadaceae family, and propionic acid with Tissierella. Taken together, administration of 15% CP showed less production of odorous compounds than 20% CP group and this result might be associated with the changes in bacterial communities especially whose roles in protein metabolism.

  2. Ocorrência de microrganismos anaeróbios estritos no escarro de pacientes com bronquite crônica

    Directory of Open Access Journals (Sweden)

    Jorge R. Spitz

    1974-06-01

    Full Text Available No escarro de pacientes hospitalizados com bronquite crônica foram isolados microrganismos anaeróbios estritos - Fusobacterium, Veillonella, Bacteroides melaninogenicus, Peptrostreptococcus, Actinomyces ou difteróides anaeróbios. Como o isolamento de anaeróbios estritos foi realizado em alíquotas da diluição 1O-³ do escarro fluidificado e em 83% dos casos não houve isolamento simultâneo no material do orofaringe, considera-se como de origem brônquica os anaeróbios isolados e não como contaminação do escarro no orofaringe e cavidade oral.Strict anaerobic microrganisms (Fusobacterium, Veillonella, Bacteroides melaninogenicus, Peptostreptococcus, Actinomyces or anaerobic "diphtheroids' were isolated from expectorated sputum of hospitalized patients with chronic bronchitis. It is noteworthy that the anaerobic microorganisms were isolated from. 10-³ dilution of fluidified sputum and were not recovered from pharyngeal cultures in 83% of the isolates. These results indicate the bronchial origin of the strict anaerobic microorganisms and can not borne out the conclusion that sputum was contaminated with the anaerobic bacteria in pharynx and oral cavity.

  3. Comparative study on the in vitro effects of Pseudomonas aeruginosa and seaweed alginates on human gut microbiota

    Science.gov (United States)

    Bai, Shaofeng; Chen, Huahai; Zhu, Liying; Liu, Wei; Yu, Hongwei D.; Wang, Xin; Yin, Yeshi

    2017-01-01

    Alginates pertain to organic polysaccharides that have been extensively used in food- and medicine-related industries. The present study obtained alginates from an alginate overproducing Pseudomonas aeruginosa PAO1 mutant by screening transposon mutagenesis libraries. The interaction between bacterial and seaweed alginates and gut microbiota were further studied by using an in vitro batch fermentation system. Thin-layer chromatography (TLC) analysis indicated that both bacterial and seaweed alginates can be completely degraded by fecal bacteria isolated from study volunteers, indicating that a minor structural difference between bacterial and seaweed alginates (O-acetylation and lack of G-G blocks) didn’t affect the digestion of alginates by human microbiota. Although, the digestion of bacterial and seaweed alginates was attributed to different Bacteroides xylanisolvens strains, they harbored similar alginate lyase genes. Genus Bacteroides with alginate-degrading capability were enriched in growth medium containing bacterial or seaweed alginates after in vitro fermentation. Short-chain fatty acid (SCFA) production in both bacterial and seaweed alginates was also comparable, but was significantly higher than the same medium using starch. In summary, the present study has isolated an alginate-overproducing P. aeruginosa mutant strain. Both seaweed and bacterial alginates were degraded by human gut microbiota, and their regulatory function on gut microbiota was similar. PMID:28170428

  4. Rhizobium leguminosarum bv. viciae 3841 Adapts to 2,4-Dichlorophenoxyacetic Acid with “Auxin-Like” Morphological Changes, Cell Envelope Remodeling and Upregulation of Central Metabolic Pathways

    Science.gov (United States)

    Bhat, Supriya V.; Booth, Sean C.; McGrath, Seamus G. K.; Dahms, Tanya E. S.

    2015-01-01

    There is a growing need to characterize the effects of environmental stressors at the molecular level on model organisms with the ever increasing number and variety of anthropogenic chemical pollutants. The herbicide 2,4-dichlorophenoxyacetic acid (2,4-D), as one of the most widely applied pesticides in the world, is one such example. This herbicide is known to have non-targeted undesirable effects on humans, animals and soil microbes, but specific molecular targets at sublethal levels are unknown. In this study, we have used Rhizobium leguminosarum bv. viciae 3841 (Rlv) as a nitrogen fixing, beneficial model soil organism to characterize the effects of 2,4-D. Using metabolomics and advanced microscopy we determined specific target pathways in the Rlv metabolic network and consequent changes to its phenotype, surface ultrastructure, and physical properties during sublethal 2,4-D exposure. Auxin and 2,4-D, its structural analogue, showed common morphological changes in vitro which were similar to bacteroids isolated from plant nodules, implying that these changes are related to bacteroid differentiation required for nitrogen fixation. Rlv showed remarkable adaptation capabilities in response to the herbicide, with changes to integral pathways of cellular metabolism and the potential to assimilate 2,4-D with consequent changes to its physical and structural properties. This study identifies biomarkers of 2,4-D in Rlv and offers valuable insights into the mode-of-action of 2,4-D in soil bacteria. PMID:25919284

  5. Rhizobium leguminosarum bv. viciae 3841 Adapts to 2,4-Dichlorophenoxyacetic Acid with "Auxin-Like" Morphological Changes, Cell Envelope Remodeling and Upregulation of Central Metabolic Pathways.

    Science.gov (United States)

    Bhat, Supriya V; Booth, Sean C; McGrath, Seamus G K; Dahms, Tanya E S

    2014-01-01

    There is a growing need to characterize the effects of environmental stressors at the molecular level on model organisms with the ever increasing number and variety of anthropogenic chemical pollutants. The herbicide 2,4-dichlorophenoxyacetic acid (2,4-D), as one of the most widely applied pesticides in the world, is one such example. This herbicide is known to have non-targeted undesirable effects on humans, animals and soil microbes, but specific molecular targets at sublethal levels are unknown. In this study, we have used Rhizobium leguminosarum bv. viciae 3841 (Rlv) as a nitrogen fixing, beneficial model soil organism to characterize the effects of 2,4-D. Using metabolomics and advanced microscopy we determined specific target pathways in the Rlv metabolic network and consequent changes to its phenotype, surface ultrastructure, and physical properties during sublethal 2,4-D exposure. Auxin and 2,4-D, its structural analogue, showed common morphological changes in vitro which were similar to bacteroids isolated from plant nodules, implying that these changes are related to bacteroid differentiation required for nitrogen fixation. Rlv showed remarkable adaptation capabilities in response to the herbicide, with changes to integral pathways of cellular metabolism and the potential to assimilate 2,4-D with consequent changes to its physical and structural properties. This study identifies biomarkers of 2,4-D in Rlv and offers valuable insights into the mode-of-action of 2,4-D in soil bacteria.

  6. High-throughput sequencing reveals microbial communities in drinking water treatment sludge from six geographically distributed plants, including potentially toxic cyanobacteria and pathogens.

    Science.gov (United States)

    Xu, Hangzhou; Pei, Haiyan; Jin, Yan; Ma, Chunxia; Wang, Yuting; Sun, Jiongming; Li, Hongmin

    2018-04-10

    The microbial community structures of drinking water treatment sludge (DWTS) generated for raw water (RW) from different locations and with different source types - including river water, lake water and reservoir water -were investigated using high-throughput sequencing. Because the unit operations in the six DWTPs were similar, community composition in fresh sludge may be determined by microbial community in the corresponding RW. Although Proteobacteria, Cyanobacteria, Bacteroidetes, Firmicutes, Verrucomicrobia, and Planctomycetes were the dominant phyla among the six DWTS samples, no single phylum exhibited similar abundance across all the samples, owing to differences in total phosphorus, chemical oxygen demand, Al, Fe, and chloride in RW. Three genera of potentially toxic cyanobacteria (Planktothrix, Microcystis and Cylindrospermopsis), and four potential pathogens (Escherichia coli, Bacteroides ovatus, Prevotella copri and Rickettsia) were found in sludge samples. Because proliferation of potentially toxic cyanobacteria and Rickettsia in RW was mainly affected by nutrients, while growth of Escherichia coli, Bacteroides ovatus and Prevotella copri in RW may be influenced by Fe, control of nutrients and Fe in RW is essential to decrease toxic cyanobacteria and pathogens in DWTS. Copyright © 2018 Elsevier B.V. All rights reserved.

  7. Diversity and characterization of ramie-degumming strains

    Directory of Open Access Journals (Sweden)

    Shengwen Duan

    2012-04-01

    Full Text Available Ramie (Boehmeria nivea and Boehmeria tenacissima is a widely used fiber crop. Traditional water retting or chemical boiling method performed in order to extract ramie fiber seriously pollute the environment and severely damage the fiber, so biological method is the general trend of the fiber-extracting industry. Some strains (687, involving 26 genera and 43 species, were collected from the three samples, which produce hydrolyzed circles in the selective culture medium in order to detect the degumming effect and to compare the enzyme activity. Among these strains, 13 of them did not produce cellulase and had a ramie decreasing weight rate above 25 %, which were regarded as efficient ramie-degumming strains named from R1 to R13. R1 to R13 belonged to Amycolata autotrobutylicun, Bacillus subtilis, Clostridium acetobutylicum, Bacillus subtilis, Rhizobium leguminosarum, Bacteroides finegoldii, Streptomyces lividans, Bacillus amyloliquefaciens, Clostridium acetobutylicum, Pseudomonas brassicacearum, Bacillus pumilus, Bacillus licheniformis, Pectobacterium wasabiae respectively. Bacteroides sp., Rhizobium sp. and Pseudomonas sp. were firstly reported to be used in ramie-degumming. At the same time, the pectinase was the key enzyme in the ramie-degumming process.

  8. Evaluation of fecal microorganisms of children with cleft palate before and after palatoplasty

    Directory of Open Access Journals (Sweden)

    Narciso Almeida Vieira

    2013-09-01

    Full Text Available This study isolated and quantified intestinal bacteria of children with cleft palate before and after palatoplasty. A prospective study was conducted from May 2007 to September 2008 on 18 children with cleft palate, aged one to four years, of both genders, attending a tertiary cleft center in Brazil for palatoplasty, to analyze the effect of surgical palate repair on the concentration of anaerobes Bacteroides sp, Bifidobacterium sp and microaerophiles Lactobacillus sp in feces of infants with cleft palate before and 24 hours after treatment with cefazolin for palatoplasty. There was significant reduction of Lactobacillus sp (p < 0.002, Bacteroides sp (p < 0.001 and Bifidobacterium sp (p = 0.021 after palatoplasty, revealing that surgery and utilization of cefazolin significantly influenced the fecal microbiota comparing collections before and after surgery. However, due to study limitations, it was not possible to conclude that other isolated factors, such as surgical stress, anesthetics and other medications used in palatoplasty might have a significant influence on the microbiota. Considering the important participation of the intestinal microbiota on both local and systemic metabolic and immunological activities of the host, professionals should be attentive to the possible influence of these changes in patients submitted to cleft repair.

  9. Comparative cytotoxicity of periodontal bacteria

    Energy Technology Data Exchange (ETDEWEB)

    Stevens, R.H.; Hammond, B.F.

    1988-11-01

    The direct cytotoxicity of sonic extracts (SE) from nine periodontal bacteria for human gingival fibroblasts (HGF) was compared. Equivalent dosages (in terms of protein concentration) of SE were used to challenge HGF cultures. The cytotoxic potential of each SE was assessed by its ability to (1) inhibit HGF proliferation, as measured by direct cell counts; (2) inhibit 3H-thymidine incorporation in HGF cultures; or (3) cause morphological alterations of the cells in challenged cultures. The highest concentration (500 micrograms SE protein/ml) of any of the SEs used to challenge the cells was found to be markedly inhibitory to the HGFs by all three of the criteria of cytotoxicity. At the lowest dosage tested (50 micrograms SE protein/ml); only SE from Actinobacillus actinomycetemcomitans, Bacteroides gingivalis, and Fusobacterium nucleatum caused a significant effect (greater than 90% inhibition or overt morphological abnormalities) in the HGFs as determined by any of the criteria employed. SE from Capnocytophaga sputigena, Eikenella corrodens, or Wolinella recta also inhibited cell proliferation and thymidine incorporation at this dosage; however, the degree of inhibition (5-50%) was consistently, clearly less than that of the first group of three organisms named above. The SE of the three other organisms tested (Actinomyces odontolyticus, Bacteroides intermedius, and Streptococcus sanguis) had little or no effect (0-10% inhibition) at this concentration. The data suggest that the outcome of the interaction between bacterial components and normal resident cells of the periodontium is, at least in part, a function of the bacterial species.

  10. Current trends in the diagnosis and treatment of tuboovarian abscess

    International Nuclear Information System (INIS)

    Landers, D.V.; Sweet, R.L.

    1985-01-01

    Tuboovarian abscess is a well-recognized complication of acute salpingitis and has been reported in as many as one third of hospital admissions for acute salpingitis. The incidence of tuboovarian abscess is expected to increase as a result of the current epidemic of sexually transmitted diseases and their sequelae. Patients with tuboovarian abscess most commonly present with lower abdominal pain and an adnexal mass(es). Fever and leukocytosis may be absent. Ultrasound, computed tomographic scans, laparoscopy, or laparotomy may be necessary to confirm the diagnosis. Tuboovarian abscess may be unilateral or bilateral regardless of intrauterine contraceptive device usage. Tuboovarian abscess is polymicrobial with a preponderance of anaerobic organisms. An initial conservative antimicrobial approach to the management of the unruptured tuboovarian abscess is appropriate if the antimicrobial agents used can penetrate abscesses, remain active within the abscess environment, and are active against the major pathogens in tuboovarian abscess, including the resistant gram-negative anaerobes such as Bacteroides fragilis and Bacteroides bivius. However, if the patient does not begin to show a response within a reasonable amount of time, about 48 to 72 hours, surgical intervention should be undertaken. Suspicion of rupture should remain an indication for immediate operation. Once operation is undertaken, a conservative approach with unilateral adnexectomy for one-side tuboovarian abscess is appropriate if future fertility or hormone production is desired

  11. Comparative study on the in vitro effects of Pseudomonas aeruginosa and seaweed alginates on human gut microbiota.

    Science.gov (United States)

    Bai, Shaofeng; Chen, Huahai; Zhu, Liying; Liu, Wei; Yu, Hongwei D; Wang, Xin; Yin, Yeshi

    2017-01-01

    Alginates pertain to organic polysaccharides that have been extensively used in food- and medicine-related industries. The present study obtained alginates from an alginate overproducing Pseudomonas aeruginosa PAO1 mutant by screening transposon mutagenesis libraries. The interaction between bacterial and seaweed alginates and gut microbiota were further studied by using an in vitro batch fermentation system. Thin-layer chromatography (TLC) analysis indicated that both bacterial and seaweed alginates can be completely degraded by fecal bacteria isolated from study volunteers, indicating that a minor structural difference between bacterial and seaweed alginates (O-acetylation and lack of G-G blocks) didn't affect the digestion of alginates by human microbiota. Although, the digestion of bacterial and seaweed alginates was attributed to different Bacteroides xylanisolvens strains, they harbored similar alginate lyase genes. Genus Bacteroides with alginate-degrading capability were enriched in growth medium containing bacterial or seaweed alginates after in vitro fermentation. Short-chain fatty acid (SCFA) production in both bacterial and seaweed alginates was also comparable, but was significantly higher than the same medium using starch. In summary, the present study has isolated an alginate-overproducing P. aeruginosa mutant strain. Both seaweed and bacterial alginates were degraded by human gut microbiota, and their regulatory function on gut microbiota was similar.

  12. Characterisation of the human uterine microbiome in non-pregnant women through deep sequencing of the V1-2 region of the 16S rRNA gene

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    Hans Verstraelen

    2016-01-01

    Full Text Available Background. It is widely assumed that the uterine cavity in non-pregnant women is physiologically sterile, also as a premise to the long-held view that human infants develop in a sterile uterine environment, though likely reflecting under-appraisal of the extent of the human bacterial metacommunity. In an exploratory study, we aimed to investigate the putative presence of a uterine microbiome in a selected series of non-pregnant women through deep sequencing of the V1-2 hypervariable region of the 16S ribosomal RNA (rRNA gene.Methods. Nineteen women with various reproductive conditions, including subfertility, scheduled for hysteroscopy and not showing uterine anomalies were recruited. Subjects were highly diverse with regard to demographic and medical history and included nulliparous and parous women. Endometrial tissue and mucus harvesting was performed by use of a transcervical device designed to obtain endometrial biopsy, while avoiding cervicovaginal contamination. Bacteria were targeted by use of a barcoded Illumina MiSeq paired-end sequencing method targeting the 16S rRNA gene V1-2 region, yielding an average of 41,194 reads per sample after quality filtering. Taxonomic annotation was pursued by comparison with sequences available through the Ribosomal Database Project and the NCBI database.Results. Out of 183 unique 16S rRNA gene amplicon sequences, 15 phylotypes were present in all samples. In some 90% of the women included, community architecture was fairly similar inasmuch B. xylanisolvens, B. thetaiotaomicron, B. fragilis and an undetermined Pelomonas taxon constituted over one third of the endometrial bacterial community. On the singular phylotype level, six women showed predominance of L. crispatus or L. iners in the presence of the Bacteroides core. Two endometrial communities were highly dissimilar, largely lacking the Bacteroides core, one dominated by L. crispatus and another consisting of a highly diverse community, including

  13. Intestinal Metagenomes and Metabolomes in Healthy Young Males: Inactivity and Hypoxia Generated Negative Physiological Symptoms Precede Microbial Dysbiosis

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    Robert Šket

    2018-03-01

    Full Text Available We explored the metagenomic, metabolomic and trace metal makeup of intestinal microbiota and environment in healthy male participants during the run-in (5 day and the following three 21-day interventions: normoxic bedrest (NBR, hypoxic bedrest (HBR and hypoxic ambulation (HAmb which were carried out within a controlled laboratory environment (circadian rhythm, fluid and dietary intakes, microbial bioburden, oxygen level, exercise. The fraction of inspired O2 (FiO2 and partial pressure of inspired O2 (PiO2 were 0.209 and 133.1 ± 0.3 mmHg for the NBR and 0.141 ± 0.004 and 90.0 ± 0.4 mmHg (~4,000 m simulated altitude for HBR and HAmb interventions, respectively. Shotgun metagenomes were analyzed at various taxonomic and functional levels, 1H- and 13C -metabolomes were processed using standard quantitative and human expert approaches, whereas metals were assessed using X-ray fluorescence spectrometry. Inactivity and hypoxia resulted in a significant increase in the genus Bacteroides in HBR, in genes coding for proteins involved in iron acquisition and metabolism, cell wall, capsule, virulence, defense and mucin degradation, such as beta-galactosidase (EC3.2.1.23, α-L-fucosidase (EC3.2.1.51, Sialidase (EC3.2.1.18, and α-N-acetylglucosaminidase (EC3.2.1.50. In contrast, the microbial metabolomes, intestinal element and metal profiles, the diversity of bacterial, archaeal and fungal microbial communities were not significantly affected. The observed progressive decrease in defecation frequency and concomitant increase in the electrical conductivity (EC preceded or took place in absence of significant changes at the taxonomic, functional gene, metabolome and intestinal metal profile levels. The fact that the genus Bacteroides and proteins involved in iron acquisition and metabolism, cell wall, capsule, virulence and mucin degradation were enriched at the end of HBR suggest that both constipation and EC decreased intestinal metal availability

  14. Susceptibility to Campylobacter infection is associated with the species composition of the human fecal microbiota.

    Science.gov (United States)

    Dicksved, Johan; Ellström, Patrik; Engstrand, Lars; Rautelin, Hilpi

    2014-09-16

    The gut microbiota is essential for human health, but very little is known about how the composition of this ecosystem can influence and respond to bacterial infections. Here we address this by prospectively studying the gut microbiota composition before, during, and after natural Campylobacter infection in exposed poultry abattoir workers. The gut microbiota composition was analyzed with 16S amplicon sequencing of fecal samples from poultry abattoir workers during the peak season of Campylobacter infection in Sweden. The gut microbiota compositions were compared between individuals who became culture positive for Campylobacter and those who remained negative. Individuals who became Campylobacter positive had a significantly higher abundance of Bacteroides (P = 0.007) and Escherichia (P = 0.002) species than those who remained culture negative. Furthermore, this group had a significantly higher abundance of Phascolarctobacterium (P = 0.017) and Streptococcus (P = 0.034) sequences than the Campylobacter-negative group, which had an overrepresentation of Clostridiales (P = 0.017), unclassified Lachnospiraceae (P = 0.008), and Anaerovorax (P = 0.015) sequences. Intraindividual comparisons of the fecal microbiota compositions yielded small differences over time in Campylobacter-negative participants, but significant long-term changes were found in the Campylobacter-positive group (P microbiota reduces resistance to Campylobacter colonization in humans and that Campylobacter infection can have long-term effects on the composition of the human fecal microbiota. Studies using mouse models have made important contributions to our understanding of the role of the gut microbiota in resistance to bacterial enteropathogen colonization. The relative abundances of Escherichia coli and Bacteroides species have been pointed out as important determinants of susceptibility to Gram-negative pathogens in general and Campylobacter infection in particular. In this study, we assessed the

  15. Obesity Alters the Microbial Community Profile in Korean Adolescents.

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    Hae-Jin Hu

    Full Text Available Obesity is an increasing public health concern worldwide. According to the latest Organization for Economic Co-operation and Development (OECD report (2014, the incidence of child obesity in Korea has exceeded the OECD average. To better understand and control this condition, the present study examined the composition of the gut microbial community in normal and obese adolescents. Fecal samples were collected from 67 obese (body mass index [BMI] ≥ 30 kg/m2, or ≥ 99th BMI percentile and 67 normal (BMI < 25 kg/m2 or < 85th BMI percentile Korean adolescents aged 13-16 years and subjected to 16S rRNA gene sequencing. Analysis of bacterial composition according to taxonomic rank (genus, family, and phylum revealed marked differences in the Bacteroides and Prevotella populations in normal and obese samples (p < 0.005 at the genus and family levels; however, there was no difference in the Firmicutes-to-Bacteroidetes (F/B ratio between normal and obese adolescents samples at the phylum level (F/B normal = 0.50 ± 0.53; F/B obese = 0.56 ± 0.86; p = 0.384. Statistical analysis revealed a significant association between the compositions of several bacterial taxa and child obesity. Among these, Bacteroides and Prevotella showed the most significant association with BMI (p < 0.0001 and 0.0001, respectively. We also found that the composition of Bacteroides was negatively associated with triglycerides (TG, total cholesterol, and high-sensitive C-reactive protein (hs-crp (p = 0.0049, 0.0023, and 0.0038, respectively levels, whereas that of Prevotella was positively associated with TG and hs-crp levels (p = 0.0394 and 0.0150, respectively. We then applied the association rule mining algorithm to generate "rules" to identify the association between the populations of multiple bacterial taxa and obesity; these rules were able to discriminate obese from normal states. Therefore, the present study describes a systemic approach to identify the association

  16. Relationship of intestinal flora disorder with TLR/NK-kB and inflammatory mediator expression in patients with ulcerative colitis

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    Ma Tao

    2017-07-01

    Full Text Available Objective: To study the relationship of intestinal flora disorder with TLR/NK-kB and inflammatory mediator expression in patients with ulcerative colitis (UC. Methods: Patients who were diagnosed with UC in Yan’an People’s Hospital between May 2015 and February 2017 were selected, patients with active UC and patients with remission UC were included in the AUC and RUC group; patients who were diagnosed with colonic polyps in Yan’an People’s Hospital through physical examination during the same period were selected as the control group. Feces was collected to test the flora number, mucosa lesion was collected to determine the expression of TLR/NK-kB and inflammatory mediators, and serum was collected to detect the levels of inflammatory mediators. Results: Bifidobacterium, lactobacillus acidophilus and bacteroides number in feces of AUC group and RUC group were significantly lower than those of control group while escherichia coli and enterococcus number in feces, TLR2, TLR4, TLR5, TLR9, NK-kB, HMGB1, TNF-α, IL-6 and IL-17 mRNA expression in intestinal mucosa lesion as well as HMGB1, TNF-α, IL-6 and IL-17 levels in serum were significantly higher than those of control group; bifidobacterium, lactobacillus acidophilus and bacteroides number in feces of AUC group were significantly lower than those of RUC group while escherichia coli and enterococcus number in feces, TLR2, TLR4, TLR5, TLR9, NKkB, HMGB1, TNF-α, IL-6 and IL-17 mRNA expression in intestinal mucosa lesion as well as HMGB1, TNF-α, IL-6 and IL-17 levels in serum were significantly higher than those of RUC group; TLR2, TLR4, TLR5, TLR9, NK-kB, HMGB1, TNF-α, IL-6 and IL-17 mRNA expression in intestinal mucosa lesion as well as HMGB1, TNF-α, IL-6 and IL-17 levels in serum were negatively correlated with bifidobacteria, lactobacillus acidophilus and bacteroides number, and positively correlated with escherichia coli and enterococcus number. Conclusion: The intestinal flora

  17. Illumina Sequencing Approach to Characterize Thiamine Metabolism Related Bacteria and the Impacts of Thiamine Supplementation on Ruminal Microbiota in Dairy Cows Fed High-Grain Diets

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    Xiaohua Pan

    2017-09-01

    Full Text Available The requirements of thiamine in adult ruminants are mainly met by ruminal bacterial synthesis, and thiamine deficiencies will occur when dairy cows overfed with high grain diet. However, there is limited knowledge with regard to the ruminal thiamine synthesis bacteria, and whether thiamine deficiency is related to the altered bacterial community by high grain diet is still unclear. To explore thiamine synthesis bacteria and the response of ruminal microbiota to high grain feeding and thiamine supplementation, six rumen-cannulated Holstein cows were randomly assigned into a replicated 3 × 3 Latin square design trial. Three treatments were control diet (CON, 20% dietary starch, DM basis, high grain diet (HG, 33.2% dietary starch, DM basis and high grain diet supplemented with 180 mg thiamine/kg DMI (HG+T. On day 21 of each period, rumen content samples were collected at 3 h postfeeding. Ruminal thiamine concentration was detected by high performance liquid chromatography. The microbiota composition was determined using Illumina MiSeq sequencing of 16S rRNA gene. Cows receiving thiamine supplementation had greater ruminal pH value, acetate and thiamine content in the rumen. Principal coordinate analysis and similarity analysis indicated that HG feeding and thiamine supplementation caused a strong shift in bacterial composition and structure in the rumen. At the genus level, compared with CON group, the relative abundances of 19 genera were significantly changed by HG feeding. Thiamine supplementation increased the abundance of cellulolytic bacteria including Bacteroides, Ruminococcus 1, Pyramidobacter, Succinivibrio, and Ruminobacter, and their increases enhanced the fiber degradation and ruminal acetate production in HG+T group. Christensenellaceae R7, Lachnospira, Succiniclasticum, and Ruminococcaceae NK4A214 exhibited a negative response to thiamine supplementation. Moreover, correlation analysis revealed that ruminal thiamine concentration was

  18. Incidence of spontaneous bacterial peritonitis in patients with ascites. Diagnostic value of white blood cell count and pH measurement in ascitic fluid

    DEFF Research Database (Denmark)

    Storgaard, J S; Svendsen, Jesper Hastrup; Hegnhøj, J

    1991-01-01

    During a 21-month period, 65 consecutive patients admitted with ascites were included in a prospective study of the incidence of spontaneous bacterial peritonitis, and paracentesis was performed on admission. The ascitic fluid was cultured, ascitic leucocytes were counted and pH was measured...... by Escherichia coli (n = 3), coagulase negative staphylococcus (n = 1), and Bacteroides species (n = 1). Abdominal tenderness, abnormal intestinal sounds, fever and hepatic encephalopathy were equally frequent in the group with SBP and in patients with sterile ascites. Infection was not anticipated in any...... of the patients with SBP. In contrast to several previous studies, neither ascites pH nor ascites leucocyte counts were any help in obtaining a rapid diagnosis. Survival time of patients with SBP was significantly shorter than of patients without SBP....

  19. Oxygen sensitivity of various anaerobic bacteria.

    Science.gov (United States)

    Loesche, W J

    1969-11-01

    Anaerobes differ in their sensitivity to oxygen, as two patterns were recognizable in the organisms included in this study. Strict anaerobes were species incapable of agar surface growth at pO(2) levels greater than 0.5%. Species that were found to be strict anaerobes were Treponema macrodentium, Treponema denticola, Treponema oralis n. sp., Clostridium haemolyticum, Selenomonas ruminatium, Butyrivibrio fibrisolvens, Succinivibrio dextrinosolvens, and Lachnospira multiparus. Moderate anaerobes would include those species capable of growth in the presence of oxygen levels as high as 2 to 8%. The moderate anaerobes could be exposed to room atmosphere for 60 to 90 min without appreciable loss of viability. Species considered as moderate anaerobes were Bacteroides fragilis, B. melaninogenicus, B. oralis, Fusobacteria nucleatum, Clostridium novyi type A, and Peptostreptococcus elsdenii. The recognition of at least two general types of anaerobes would seem to have practical import in regard to the primary isolation of anaerobes from source material.

  20. Mode of Delivery Shapes Gut Colonization Pattern and Modulates Regulatory Immunity in Mice

    DEFF Research Database (Denmark)

    H. F. Hansen, Camilla; S. F. Andersen, Line; Krych, Łukasz

    2014-01-01

    Delivery mode has been associated with long-term changes in gut microbiota composition and more recently also with changes in the immune system. This has further been suggested to link Cesarean section (C-section) with an increased risk for development of immune-mediated diseases such as type 1...... revealed that mice born by C-section had a distinct bacterial profile at weaning characterized by higher abundance of Bacteroides and Lachnospiraceae, and less Rikenellaceae and Ruminococcus. No clustering according to delivery method as determined by principal component analysis of denaturing gradient gel...... immune system that was also evident in NOD mice, a model of type 1 diabetes, born by C-section. However, no effect of delivery mode was seen on diabetes incidence or insulitis development. In conclusion, the first exposure to microorganisms seems to be crucial for the early life gut microbiota...

  1. Antimicrobial Activity of Diterpenes from Viguiera arenaria against Endodontic Bacteria

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    Carlos H. G. Martins

    2011-01-01

    Full Text Available Six pimarane-type diterpenes isolated from Viguiera arenaria Baker and two semi-synthetic derivatives were evaluated in vitro against a panel of representative microorganisms responsible for dental root canal infections. The microdilution method was used for the determination of the minimum inhibitory concentration (MIC and minimum bactericidal concentration (MBC against Porphyromonas gingivalis, Prevotella nigrescens, Prevotella intermedia, Prevotella buccae, Fusobacterium nucleatum, Bacteroides fragilis, Actinomyces naeslundii, Actinomyces viscosus, Peptostreptococcus micros, Enterococcus faecalis and Aggregatibacter actinomycetemcomitans. The compounds ent-pimara-8(14,15-dien-19-oic acid, its sodium salt and ent-8(14,15-pimaradien-3β-ol were the most active, displaying MIC values ranging from 1 to 10 μg mL-1. The results also allow us to conclude that minor structural differences among these diterpenes significantly influence their antimicrobial activity, bringing new perspectives to the discovery of new chemicals for use as a complement to instrumental endodontic procedures.

  2. Influence of Microbiota on Intestinal Immune System in Ulcerative Colitis and Its Intervention

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    Sai-Long Zhang

    2017-11-01

    Full Text Available Ulcerative colitis (UC is an inflammatory bowel disease (IBD with chronic and recurrent characteristics caused by multiple reasons. Although the pathogenic factors have not been clarified yet, recent studies have demonstrated that intestinal microbiota plays a major role in UC, especially in the immune system. This review focuses on the description of several major microbiota communities that affect UC and their interactions with the host. In this review, eight kinds of microbiota that are highly related to IBD, including Faecalibacterium prausnitzii, Clostridium clusters IV and XIVa, Bacteroides, Roseburia species, Eubacterium rectale, Escherichia coli, Fusobacterium, and Candida albicans are demonstrated on the changes in amount and roles in the onset and progression of IBD. In addition, potential therapeutic targets for UC involved in the regulation of microbiota, including NLRPs, vitamin D receptor as well as secreted proteins, are discussed in this review.

  3. [Microbial flora and antibiotic susceptibility of purulent tooth diseases in rabbits].

    Science.gov (United States)

    Ewringmann, Anja

    2017-11-03

    Bacteria involved in purulent tooth disease and the most effective antibiotics were investigated. Swab samples were taken from 126 rabbits with facial abscesses or purulent periapical inflammation during surgical treatment. Bacteriological examination and susceptibility testing were performed. A wide range of aerobic and anaerobic bacteria were detected. The most commonly isolated anaerobes were gram-negative rods (Prevotella sp., Fusobacterium sp., Bacteroides sp.) and gram-positive non-sporulating cocci (mostly Peptostreptococcus sp.). Of the aerobes, 66.7% were gram-negative (mostly Pasteurella sp., Escherichia coli, Pseudomonas sp.) while 33.3% were gram-positive (mostly Streptococcus sp., Staphylococcus sp.). Depending on the individual patients, fluoroquinolones in combination with amoxicillin-clavulanate, chloramphenicol, amoxicillin-clavulanate, tetracyclines, pradofloxacin, and fluoroquinolone-metronidazole-combinations were most effective. Because of the variability of the detected bacteria, considerable differences in antibiotic susceptibility were observed. Therefore, bacterial examination and susceptibility testing are recommended for effective postsurgical treatment of odontogenic abscesses in rabbits.

  4. Prebiotic properties of potato starch dextrins.

    Science.gov (United States)

    Barczyńska, Renata; Śliżewska, Katarzyna; Libudzisz, Zdzisława; Kapuśniak, Kamila; Kapuśniak, Janusz

    2015-09-08

    The objective of the present study was to compare the prebiotic properties of starch dextrins, that is, resistant dextrins obtained from potato starch in the process of simultaneous thermolysis and chemical modification, which were selected based on previous research. Both prepared dextrins met the definition criterion of dietary fiber and also the basic prebiotic criterion - they were not degraded by the digestive enzymes of the initial sections of the gastrointestinal tract. The growth of probiotic lactobacilli and bifidobacteria, as well as Escherichia coli, Enterococcus, Bacteroides, and Clostridium strains isolated from feces of healthy people, showed that both studied dextrins were utilized as a source of assimilable carbon and energy by the strains. Furthermore, better growth (higher numbers of cells) counts of probiotic bacteria than those of fecal isolates indicated that the studied resistant dextrins showed a selective effect. Both dextrins might be considered as substances with prebiotic properties due to their chemical and physical properties and selectivity towards the studied probiotic bacterial strains.

  5. Synthetic Biology Approaches to Engineer Probiotics and Members of the Human Microbiota for Biomedical Applications.

    Science.gov (United States)

    Bober, Josef R; Beisel, Chase L; Nair, Nikhil U

    2018-03-12

    An increasing number of studies have strongly correlated the composition of the human microbiota with many human health conditions and, in several cases, have shown that manipulating the microbiota directly affects health. These insights have generated significant interest in engineering indigenous microbiota community members and nonresident probiotic bacteria as biotic diagnostics and therapeutics that can probe and improve human health. In this review, we discuss recent advances in synthetic biology to engineer commensal and probiotic lactic acid bacteria, bifidobacteria, and Bacteroides for these purposes, and we provide our perspective on the future potential of these technologies. 277 Expected final online publication date for the Annual Review of Biomedical Engineering Volume 20 is June 4, 2018. Please see http://www.annualreviews.org/page/journal/pubdates for revised estimates.

  6. Effect of radiation-induced xerostomia on the human oral microflora. Report no. 12 (final), 1 Jul 1971-30 Jun 1976

    Energy Technology Data Exchange (ETDEWEB)

    Dreizen, S.; Brown, L.R.

    1976-06-30

    The caries-conducive impact of xerostomia was studied in 42 irradiated cancer patients. The radiation-induced xerostomia was paralleled by changes in the physical, microbial, biochemical, immunologic and dietary parameters of cariogenicity that collectively comprised an overwhelming caries challenge. Microbiologically, significant xerostomia-related increases in Strep. mutans, lactobacilli, staphylococci, yeasts and catalase-positive diphtheroids were accompanied by decreases in Strep. sanguis, bacteroides and fusobacteria in each of the 5 microenvironments tested. The scanty xerostomic saliva contained greater amounts of Na(+), Cl(-), Ca(++), Mg(++), Prot(-), lysozyme, IgA and IgG and considerably less HCO3(-). The increased concentrations of caries protective electrolytes and immunoproteins were negated by huge reductions in total daily saliva output. The xerostomia created caries challenge was almost completely neutralized by a preventive program of daily topical NaF applications and strict oral hygiene. (GRA)

  7. Gut microbiome and serum metabolome alterations in obesity and after weight-loss intervention.

    Science.gov (United States)

    Liu, Ruixin; Hong, Jie; Xu, Xiaoqiang; Feng, Qiang; Zhang, Dongya; Gu, Yanyun; Shi, Juan; Zhao, Shaoqian; Liu, Wen; Wang, Xiaokai; Xia, Huihua; Liu, Zhipeng; Cui, Bin; Liang, Peiwen; Xi, Liuqing; Jin, Jiabin; Ying, Xiayang; Wang, Xiaolin; Zhao, Xinjie; Li, Wanyu; Jia, Huijue; Lan, Zhou; Li, Fengyu; Wang, Rui; Sun, Yingkai; Yang, Minglan; Shen, Yuxin; Jie, Zhuye; Li, Junhua; Chen, Xiaomin; Zhong, Huanzi; Xie, Hailiang; Zhang, Yifei; Gu, Weiqiong; Deng, Xiaxing; Shen, Baiyong; Xu, Xun; Yang, Huanming; Xu, Guowang; Bi, Yufang; Lai, Shenghan; Wang, Jian; Qi, Lu; Madsen, Lise; Wang, Jiqiu; Ning, Guang; Kristiansen, Karsten; Wang, Weiqing

    2017-07-01

    Emerging evidence has linked the gut microbiome to human obesity. We performed a metagenome-wide association study and serum metabolomics profiling in a cohort of lean and obese, young, Chinese individuals. We identified obesity-associated gut microbial species linked to changes in circulating metabolites. The abundance of Bacteroides thetaiotaomicron, a glutamate-fermenting commensal, was markedly decreased in obese individuals and was inversely correlated with serum glutamate concentration. Consistently, gavage with B. thetaiotaomicron reduced plasma glutamate concentration and alleviated diet-induced body-weight gain and adiposity in mice. Furthermore, weight-loss intervention by bariatric surgery partially reversed obesity-associated microbial and metabolic alterations in obese individuals, including the decreased abundance of B. thetaiotaomicron and the elevated serum glutamate concentration. Our findings identify previously unknown links between intestinal microbiota alterations, circulating amino acids and obesity, suggesting that it may be possible to intervene in obesity by targeting the gut microbiota.

  8. Utilization of algal polysaccharides by human colonic bacteria, in axenic culture or in association with hydrogenotrophic microorganisms.

    Science.gov (United States)

    Rochet, V; Bernalier, A

    1997-01-01

    The ability of different hydrolytic bacteria from the human colon to grow on various algal polymers (carrageenans, Palmaria palmata xylan, ulvan, desulphated ulvan and laminaran) was investigated and the interactions between Bacteroides thetaiotaomicron and H2-utilizing microorganisms (one methanogenic archaea and an acetogenic bacterium) were studied during laminaran degradation. None of the algal polysaccharides supported the growth of any of the hydrolytic species tested, except for laminaran, which allowed substantial growth of B thetaiotaomicron. This suggested that bacterial consortia were involved in algal polymer breakdown rather than one specific bacterial species. The presence of H2-utilizing microorganisms did not increase the extent of laminaran degradation by B thetaiotaomicron. Whereas the decrease in formate and H2 concentrations attested to their utilization by both hydrogenotrophic microorganisms, the large increase in acetate production observed in the coculture with acetogenic bacteria was mainly due to acetogenic fermentation of sugars released during laminaran hydrolysis.

  9. Function and structure relationships of a β-1,2-glucooligosaccharide-degrading β-glucosidase.

    Science.gov (United States)

    Ishiguro, Rikuto; Tanaka, Nobukiyo; Abe, Koichi; Nakajima, Masahiro; Maeda, Takuma; Miyanaga, Akimasa; Takahashi, Yuta; Sugimoto, Naohisa; Nakai, Hiroyuki; Taguchi, Hayao

    2017-12-01

    BT_3567 protein, a putative β-glucosidase from Bacteroides thetaiotaomicron, exhibits higher activity toward Sop 3-5 (Sop n , n: degree of polymerization of β-1,2-glucooligosaccharides) than toward Sop 2 , unlike a known β-glucosidase from Listeria innocua which predominantly prefers Sop 2 . In the complex structure determined by soaking of a D286N mutant crystal with Sop 4 , a Sop 3 moiety was observed at subsites -1 to +2. The glucose moiety at subsite +2 forms a hydrogen bond with Asn81, which is replaced with Gly in the L. innocua β-glucosidase. The K m values of the N81G mutant for Sop 3-5 are much higher than those of the wild-type, suggesting that Asn81 contributes to the binding to substrates longer than Sop 3 . © 2017 Federation of European Biochemical Societies.

  10. Molecular basis of an agarose metabolic pathway acquired by a human intestinal symbiont.

    Science.gov (United States)

    Pluvinage, Benjamin; Grondin, Julie M; Amundsen, Carolyn; Klassen, Leeann; Moote, Paul E; Xiao, Yao; Thomas, Dallas; Pudlo, Nicholas A; Anele, Anuoluwapo; Martens, Eric C; Inglis, G Douglas; Uwiera, Richard E R; Boraston, Alisdair B; Abbott, D Wade

    2018-03-13

    In red algae, the most abundant principal cell wall polysaccharides are mixed galactan agars, of which agarose is a common component. While bioconversion of agarose is predominantly catalyzed by bacteria that live in the oceans, agarases have been discovered in microorganisms that inhabit diverse terrestrial ecosystems, including human intestines. Here we comprehensively define the structure-function relationship of the agarolytic pathway from the human intestinal bacterium Bacteroides uniformis (Bu) NP1. Using recombinant agarases from Bu NP1 to completely depolymerize agarose, we demonstrate that a non-agarolytic Bu strain can grow on GAL released from agarose. This relationship underscores that rare nutrient utilization by intestinal bacteria is facilitated by the acquisition of highly specific enzymes that unlock inaccessible carbohydrate resources contained within unusual polysaccharides. Intriguingly, the agarolytic pathway is differentially distributed throughout geographically distinct human microbiomes, reflecting a complex historical context for agarose consumption by human beings.

  11. A retrospective study of disease in captive kangaroos from Oklahoma State University, 1995-2009.

    Science.gov (United States)

    Stern, Adam W

    2010-03-01

    The antemortem biopsy records (5 cases) and necropsy records (34 cases) were reviewed from 39 kangaroo case submissions during a 14-year period to the Oklahoma State University and the Oklahoma Animal Disease Diagnostic Laboratory. The most common types of diseases in the kangaroos, based on necropsy examination, was disease of the alimentary tract (12 cases), pneumonia (6 cases), and disseminated toxoplasmosis (5 cases). The cause of disease was not determined in 6 case submissions. Based on histopathologic findings, clostridial enteritis/colitis was suspected in 2 kangaroos. Coccidian parasites were identified within histologic sections of the small intestine in 1 kangaroo. Pasteurella sp. (1 case) and Bacteroides sp. (1 case) were isolated from the lung in 2 cases of pneumonia. Most (77.3%) of disease in this study in the kangaroos with known ages occurred in animals older than 1 year. Two neoplasms were detected in the antemortem biopsy samples from 1 case.

  12. Effects of α-Galactooligosaccharides from Chickpeas on High-Fat-Diet-Induced Metabolic Syndrome in Mice.

    Science.gov (United States)

    Dai, Zhuqing; Lyu, Wanyong; Xie, Minhao; Yuan, Qingxia; Ye, Hong; Hu, Bing; Zhou, Li; Zeng, Xiaoxiong

    2017-04-19

    The gut microbiota has the ability to modulate host energy homeostasis, which may regulate metabolic disorders. Functional oligosaccharide may positively regulate the intestinal microbiota. Therefore, effects of α-galactooligosaccharides (α-GOS) from chickpea on high-fat-diet (HFD)-induced metabolic syndrome and gut bacterial dysbiosis were investigated. After 6 weeks of intervention, HFD led to significant increases in levels of blood glucose, total cholesterol, triglyceride, glycated serum protein, high-density lipoprotein cholesterol, and low-density lipoprotein cholesterol of mice compared to normal-chow-fed mice. Meanwhile, all of the α-GOS-treated groups significantly decreased above parameters compared to the HFD group. HFD could significantly decrease the content of all bacteria, especially Bacteroides (9.82 ± 0.09 versus 10.3 ± 0.10; p bacterial ecosystem in a positive way.

  13. Transepithelial activation of human leukocytes by probiotics and commensal bacteria: Role of Enterobacteriaceae-type endotoxin

    DEFF Research Database (Denmark)

    Baeuerlein, Annette; Ackermann, Stefanie; Parlesak, Alexandr

    2009-01-01

    The goal of the current study was to clarify whether commercially available probiotics induce greater trans-epithelial activation of human leukocytes than do commensal, food-derived and pathogenic bacteria and to identify the compounds responsible for this activation. Eleven different bacterial...... strains, and some of their pathogen-associated molecular patterns, were incubated apically on a confluent layer of intestinal epithelial cells (Caco-2), which were basolaterally co-cultured with human mononuclear leukocytes. Only Gram-negative bacteria having Enterobacteriaceae-type endotoxin (commensal...... Escherichia coli K12, probiotic E. coli Nissle, EPEC) induced basolateral production of TNF-alpha, IFN-gamma, IL 6, 8, and 10. Gram-positive probiotics (Lactobacillus spp. and Bifidobacterium spp.) had virtually no effect. In addition, commensals (Enterococcus faecalis, Bacteroides vulgatus) and food...

  14. Transepithelial activation of human leukocytes by probiotics and commensal bacteria: role of Enterobacteriaceae-type endotoxin

    DEFF Research Database (Denmark)

    Bäuerlein, A.; Ackermann, S.; Parlesak, Alexandr

    2009-01-01

    The goal of the current study was to clarify whether commercially available probiotics induce greater trans-epithelial activation of human leukocytes than do commensal, food-derived and pathogenic bacteria and to identify the compounds responsible for this activation. Eleven different bacterial...... strains, and some of their pathogen-associated molecular patterns, were incubated apically on a confluent layer of intestinal epithelial cells (Caco-2), which were basolaterally co-cultured with human mononuclear leukocytes. Only Gram-negative bacteria having Enterobacteriaceae-type endotoxin (commensal...... Escherichia coli K12, probiotic E. coli Nissle, EPEC) induced basolateral production of TNF-alpha, IFN-gamma, IL 6, 8, and 10. Gram-positive probiotics (Lactobacillus spp. and Bifidobacterium spp.) had virtually no effect. In addition, commensals (Enterococcus faecalis, Bacteroides vulgatus) and food...

  15. Evaluation of fecal microorganisms of children with cleft palate before and after palatoplasty.

    Science.gov (United States)

    Vieira, Narciso Almeida; Borgo, Hilton Coimbra; da Silva Dalben, Gisele; Bachega, Maria Irene; Pereira, Paulo Câmara Marques

    2013-01-01

    This study isolated and quantified intestinal bacteria of children with cleft palate before and after palatoplasty. A prospective study was conducted from May 2007 to September 2008 on 18 children with cleft palate, aged one to four years, of both genders, attending a tertiary cleft center in Brazil for palatoplasty, to analyze the effect of surgical palate repair on the concentration of anaerobes Bacteroides sp, Bifidobacterium sp and microaerophiles Lactobacillus sp in feces of infants with cleft palate before and 24 hours after treatment with cefazolin for palatoplasty. There was significant reduction of Lactobacillus sp (p used in palatoplasty might have a significant influence on the microbiota. Considering the important participation of the intestinal microbiota on both local and systemic metabolic and immunological activities of the host, professionals should be attentive to the possible influence of these changes in patients submitted to cleft repair.

  16. Evaluation of antimicrobial activity of extracts of Tibouchina candolleana (melastomataceae, isolated compounds and semi-synthetic derivatives against endodontic bacteria

    Directory of Open Access Journals (Sweden)

    Fernanda M. dos Santos

    2012-06-01

    Full Text Available This work describes the phytochemical study of the extracts from aerial parts of Tibouchina candolleana as well as the evaluation of the antimicrobial activity of extracts, isolated compounds, and semi-synthetic derivatives of ursolic acid against endodontic bacteria. HRGC analysis of the n-hexane extract of T. candolleana allowed identification of b-amyrin, a-amyrin, and b-sitosterol as major constituents. The triterpenes ursolic acid and oleanolic acid were isolated from the methylene chloride extract and identified. In addition, the flavonoids luteolin and genistein were isolated from the ethanol extract and identified. The antimicrobial activity was investigated via determination of the minimum inhibitory concentration (MIC using the broth microdilution method. Amongst the isolated compounds, ursolic acid was the most effective against the selected endodontic bacteria. As for the semi-synthetic ursolic acid derivatives, only the methyl ester derivative potentiated the activity against Bacteroides fragilis.

  17. Eating for two: how metabolism establishes interspecies interactions in the gut.

    Science.gov (United States)

    Fischbach, Michael A; Sonnenburg, Justin L

    2011-10-20

    In bacterial communities, "tight economic times" are the norm. Of the many challenges bacteria face in making a living, perhaps none are more important than generating energy, maintaining redox balance, and acquiring carbon and nitrogen to synthesize primary metabolites. The ability of bacteria to meet these challenges depends heavily on the rest of their community. Indeed, the most fundamental way in which bacteria communicate is by importing the substrates for metabolism and exporting metabolic end products. As an illustration of this principle, we will travel down a carbohydrate catabolic pathway common to many species of Bacteroides, highlighting the interspecies interactions established (often inevitably) at its key steps. We also discuss the metabolic considerations in maintaining the stability of host-associated microbial communities. Copyright © 2011 Elsevier Inc. All rights reserved.

  18. Utilization of 14C-labelled cellulose in conventional, germ-free and mono-associated rats

    International Nuclear Information System (INIS)

    Juhr, N.C.; Franke, J.; Ratsch, H.

    1987-01-01

    This report deals with the ultilization of 14 C-labelled cellulose in conventional, defined associated, and germ-free rats. With conventional animals 35.8% of the administered 14 C dose can be demonstrated in the exhaled air, 5.9% in organs, and 3.9% in the urine. 58.6% could be identified as not utilized in the intestinal and fecal contents. Animals mono-associated with Bacteroides succinogenes have about the same utilization rate. The appearance of 14 C in the exhaled air, in organs and the urine of germ-free animals is caused by a part of 14 C-labelled starch in the used test material. (author)

  19. Bacteriology of diabetic foot lesions

    Directory of Open Access Journals (Sweden)

    Anandi C

    2004-01-01

    Full Text Available Clinical grading and bacteriological study of 107 patients with diabetic foot lesions revealed polymicrobial aetiology in 69 (64.4% and single aetiology in 21 (19.6%. Among 107 patients 62 had ulcer. Of these 31 had mixed aerobes. Twenty six patients with cellulitis and 12 with gangrene had more than 5 types of aerobes and anaerobes such as E.coli, Klebsiella spp., Pseudomonas spp., Proteus spp., Enterobactor spp., Enterococci spp., Clostridium perfringens, Bacteroides spp., Prevotella spp. and Peptostreptococcus spp. It was noted that 50 out of 62 patients with ulcer, and all the patients with cellulitis and gangrene were given surgical management and treated with appropriate antibiotics based on antimicrobial susceptibility testing.

  20. A conformational switch in the active site of BT_2972, a methyltransferase from an antibiotic resistant pathogen B. thetaiotaomicron.

    Directory of Open Access Journals (Sweden)

    Veerendra Kumar

    Full Text Available Methylation is one of the most common biochemical reactions involved in cellular and metabolic functions and is catalysed by the action of methyltransferases. Bacteroides thetaiotaomicron is an antibiotic-resistant bacterium that confers resistance through methylation, and as yet, there is no report on the structure of methyltransferases from this bacterium. Here, we report the crystal structure of an AdoMet-dependent methyltransferase, BT_2972 and its complex with AdoMet and AdoHcy for B. thetaiotaomicron VPI-5482 strain along with isothermal titration calorimetric assessment of the binding affinities. Comparison of the apo and complexed BT_2972 structures reveals a significant conformational change between open and closed forms of the active site that presumably regulates the association with cofactors and may aid interaction with substrate. Together, our analysis suggests that BT_2972 is a small molecule methyltransferase and might catalyze two O-methylation reaction steps involved in the ubiquinone biosynthesis pathway.

  1. Isolation and identification of intestinal bacteria from Japanese tree frog (Hlya japonica) with the special reference to anaerobic bacteria.

    Science.gov (United States)

    Benno, Y; Izumi-Kurotani, A; Yamashita, M

    1992-08-01

    The bacteria in the large intestines of eight Japanese tree frogs (Hlya japonica) were enumerated by using an anaerobic culture system. The microorganisms at approximately 3.1 x 10(9) bacteria per g (wet weight) of intestinal contents were present in the intestine of all the frogs tested. No difference of the total bacteria in the frog intestine was observed between two different incubation-temperatures (room temperature and 37 degrees C). Eleven genera and 16 species were isolated from the frog intestine. In most frogs, Bacteroides (B.) caccae and B. vulgatus were detected as the predominant organisms. Escherichia coli was also present in greater numbers in the intestine. Other bacteria isolated at high dilutions were strict anaerobes, including Fusobacterium and Clostridium. Enterococcus faecalis was frequently isolated from the frog intestine. However, four genera of Bifidobacterium, Eubacterium, Peptostreptococcus, and Lactobacillus were not isolated from the frog intestine.

  2. In vitro investigations on microbial incorporation of nitrogen from [15N2]urea and [15N2]ammonium chloride by the human intestinal flora

    International Nuclear Information System (INIS)

    Stolpe, H.J.; Heine, W.; Bohnenstengel, C.M.; Gruette, F.K.; Wutzke, K.

    1987-01-01

    6 typical bacteria species of the human intestinal flora (E. coli, Klebsiella pneumoniae, Proteus vulgaris, Streptococcus faecalis, Bacteroides fragilis, Bifidobacterium sp.) were incubated in a liquid medium for 48 h with [ 15 N 2 ]urea and [ 15 N]ammonium chloride. The rates of 15 N incorporation were calculated. They depend reproducibly on the species examined, on the kind of the offered NPN substance and on the amount of NPN substance in the medium. With [ 15 N 2 ]urea the minimal rate of incorporation was 3.8% (E. coli) and the maximal one 95.6% (Bifidobacterium sp.). With [ 15 N]ammonium chloride the corresponding figures were 31.0 (Proteus vulg.) and 98.0% (Bifidobacterium sp.). The findings are discussed with regard to a possible enteral detoxification in uremic patients by bacterial utilization and elimination of urea and ammonia. (author)

  3. Unilateral failure of development of mandibular premolars and molars in an Eastern Grey kangaroo (Macropus giganteus) and its effects on molar progression.

    Science.gov (United States)

    Barber, D; Campbell, J; Davey, J; Luke, T; Agren, E; Beveridge, I

    2008-01-01

    An adult male Eastern Grey kangaroo from a wildlife reserve near Melbourne was submitted for necropsy examination and was discovered to have abnormal dentition. There was no evidence that any premolars or molars had ever been present on the right mandible, whilst the incisors were normal. The age of the kangaroo was estimated to be 1 year 9 months using the right maxillary molars and 2 years 4 months old using the contralateral side, presumably due to the asymmetry of the dental arcades. 'Lumpy jaw', a common periodontal disease of kangaroos, from which Bacteroides sp was cultured, was present on the base of the vertical ramus of the left mandible. Complete unilateral absence of premolar and molar teeth in the mandible of a kangaroo has not been described. This condition affected molar progression in both sets of maxillary molars.

  4. Nitrogen fixation and carbon metabolism in legume nodules.

    Science.gov (United States)

    Garg, Neera; Singla, Ranju; Geetanjali

    2004-02-01

    A large amount of energy is utilized by legume nodules for the fixation of nitrogen and assimilation of fixed nitrogen (ammonia) into organic compounds. The source of energy is provided in the form of photosynthates by the host plant. Phosphoenol pyruvate carboxylase (PEPC) enzyme, which is responsible for carbon dioxide fixation in C4 and crassulacean acid metabolism plants, has also been found to play an important role in carbon metabolism in legume root nodule. PEPC-mediated CO2 fixation in nodules results in the synthesis of C4 dicarboxylic acids, viz. aspartate, malate, fumarate etc. which can be transported into bacteroids with the intervention of dicarboxylate transporter (DCT) protein. PEPC has been purified from the root nodules of few legume species. Information on the relationship between nitrogen fixation and carbon metabolism through PEPC in leguminous plants is scanty and incoherent. This review summarizes the various aspects of carbon and nitrogen metabolism in legume root nodules.

  5. A nodule-specific protein secretory pathway required for nitrogen-fixing symbiosis.

    Science.gov (United States)

    Wang, Dong; Griffitts, Joel; Starker, Colby; Fedorova, Elena; Limpens, Erik; Ivanov, Sergey; Bisseling, Ton; Long, Sharon

    2010-02-26

    The nitrogen-fixing symbiosis between Sinorhizobium meliloti and its leguminous host plant Medicago truncatula occurs in a specialized root organ called the nodule. Bacteria that are released into plant cells are surrounded by a unique plant membrane compartment termed a symbiosome. We found that in the symbiosis-defective dnf1 mutant of M. truncatula, bacteroid and symbiosome development are blocked. We identified the DNF1 gene as encoding a subunit of a signal peptidase complex that is highly expressed in nodules. By analyzing data from whole-genome expression analysis, we propose that correct symbiosome development in M. truncatula requires the orderly secretion of protein constituents through coordinated up-regulation of a nodule-specific pathway exemplified by DNF1.

  6. Localization of acid phosphatase activity in the apoplast of root nodules of pea (Pisum sativum

    Directory of Open Access Journals (Sweden)

    Marzena Sujkowska

    2011-01-01

    Full Text Available Changes in the activity of acid phosphatase (AcPase in the apoplast of pea root nodule were investigated. The activity was determined using lead and cerium methods. The results indicated a following sequence of AcPase activity appearance during the development of the infection thread: 1 low AcPase activity appears in the outer part of cells of symbiotic bacteria; 2 bacteria show increased AcPase activity, and the enzyme activity appears in the thread walls; 3 activity exhibits also matrix of the infection thread; 4 bacteria just before their release from the infection threads show high AcPase activity; 5 AcPase activity ceases after bacteria transformation into bacteroids. The increase in bacterial AcPase activity may reflect a higher demand for inorganic phosphorus necessary for propagation of the bacteria within the infection threads and/or involved in bacteria release from the infection threads.

  7. Starch Catabolism by a Prominent Human Gut Symbiont Is Directed by the Recognition of Amylose Helices

    Energy Technology Data Exchange (ETDEWEB)

    Koropatkin, Nicole M.; Martens, Eric C.; Gordon, Jeffrey I.; Smith, Thomas J. (WU); (Danforth)

    2009-01-12

    The human gut microbiota performs functions that are not encoded in our Homo sapiens genome, including the processing of otherwise undigestible dietary polysaccharides. Defining the structures of proteins involved in the import and degradation of specific glycans by saccharolytic bacteria complements genomic analysis of the nutrient-processing capabilities of gut communities. Here, we describe the atomic structure of one such protein, SusD, required for starch binding and utilization by Bacteroides thetaiotaomicron, a prominent adaptive forager of glycans in the distal human gut microbiota. The binding pocket of this unique {alpha}-helical protein contains an arc of aromatic residues that complements the natural helical structure of starch and imposes this conformation on bound maltoheptaose. Furthermore, SusD binds cyclic oligosaccharides with higher affinity than linear forms. The structures of several SusD/oligosaccharide complexes reveal an inherent ligand recognition plasticity dominated by the three-dimensional conformation of the oligosaccharides rather than specific interactions with the composite sugars.

  8. Enterotypes influence temporal changes in gut microbiota

    DEFF Research Database (Denmark)

    Roager, Henrik Munch; Licht, Tine Rask; Kellebjerg Poulsen, Sanne

    The human gut microbiota plays an important role for human health. The question is whether we can modulate the gut microbiota by changing diet. During a 6-month, randomised, controlled dietary intervention, the effect of consuming a diet following the New Nordic Diet recommendations (NND......) as opposed to Average Danish Diet (ADD) on the gut microbiota in humans (n=62) was investigated. Quantitative PCR analysis showed that the microbiota did not change significantly by the intervention. Nevertheless, by stratifying subjects into two enterotypes, distinguished by the Prevotella/Bacteroides ratio...... (P/B), we were able to detect significant changes in the gut microbiota composition resulting from the interventions. Subjects with a high-P/B experienced more pronounced changes in the gut microbiota composition than subjects with a low-P/B. The study is the first to indicate that enterotypes...

  9. Enterotypes influence temporal changes in gut microbiota

    DEFF Research Database (Denmark)

    Roager, Henrik Munch; Licht, Tine Rask; Kellebjerg Poulsen, Sanne

    The human gut microbiota plays an important role for the health of the host. The question is whether we can modulate the gut microbiota by changing diet. During a 6-month, randomised, controlled dietary intervention, the effect of a moderate diet shift from Average Danish Diet to New Nordic Diet...... on the gut microbiota in humans (n=62) was investigated. Quantitative PCR analysis showed that the microbiota did not change significantly by the intervention. Nevertheless, by stratifying subjects into two enterotypes, distinguished by the Prevotella/Bacteroides ratio (P/B), we were able to detect...... significant changes in the gut microbiota composition resulting from the interventions. Subjects with a high-P/B experienced more pronounced changes in the gut microbiota composition than subjects with a low-P/B. The study is the first to indicate that enterotypes influence microbiota response to a dietary...

  10. Isolation and identification of quercetin degrading bacteria from human fecal microbes.

    Directory of Open Access Journals (Sweden)

    Zhichao Zhang

    Full Text Available Quercetin has a wide range of biological properties. The gut microflora can often modulate its biological activity and their potential health effects. There still is a lack of information about gut bacteria involving in this process. The strains of gut microbes from human feces that can transform quercetin were isolated and identified by in vitro fermentation. The results showed that Escherichia coli, Stretococcus lutetiensis, Lactobacillus acidophilus, Weissella confusa, Enterococcus gilvus, Clostridium perfringens and Bacteroides fragilis have the various ability of degrading quercetin. Among them, C. perfringens and B. fragilis were discovered to have the strongest ability of degrading quercetin. Additionally, quercetin can't inhibit the growth of C. perfringens. In conclusion, many species of gut microbiota can degrade quercetin, but their ability are different.

  11. Structure of BT-3984, a member of the SusD/RagB family of nutrient-binding molecules

    International Nuclear Information System (INIS)

    Bakolitsa, Constantina; Xu, Qingping; Rife, Christopher L.; Abdubek, Polat; Astakhova, Tamara; Axelrod, Herbert L.; Carlton, Dennis; Chen, Connie; Chiu, Hsiu-Ju; Clayton, Thomas; Das, Debanu; Deller, Marc C.; Duan, Lian; Ellrott, Kyle; Farr, Carol L.; Feuerhelm, Julie; Grant, Joanna C.; Grzechnik, Anna; Han, Gye Won; Jaroszewski, Lukasz; Jin, Kevin K.; Klock, Heath E.; Knuth, Mark W.; Kozbial, Piotr; Krishna, S. Sri; Kumar, Abhinav; Lam, Winnie W.; Marciano, David; McMullan, Daniel; Miller, Mitchell D.; Morse, Andrew T.; Nigoghossian, Edward; Nopakun, Amanda; Okach, Linda; Puckett, Christina; Reyes, Ron; Tien, Henry J.; Trame, Christine B.; Bedem, Henry van den; Weekes, Dana; Hodgson, Keith O.; Wooley, John; Elsliger, Marc-André; Deacon, Ashley M.; Godzik, Adam; Lesley, Scott A.; Wilson, Ian A.

    2010-01-01

    The crystal structure of BT-3984, a SusD-family protein, reveals a TPR N-terminal region providing support for a loop-rich C-terminal subdomain and suggests possible interfaces involved in sus complex formation. The crystal structure of the Bacteroides thetaiotaomicron protein BT-3984 was determined to a resolution of 1.7 Å and was the first structure to be determined from the extensive SusD family of polysaccharide-binding proteins. SusD is an essential component of the sus operon that defines the paradigm for glycan utilization in dominant members of the human gut microbiota. Structural analysis of BT-3984 revealed an N-terminal region containing several tetratricopeptide repeats (TPRs), while the signature C-terminal region is less structured and contains extensive loop regions. Sequence and structure analysis of BT-3984 suggests the presence of binding interfaces for other proteins from the polysaccharide-utilization complex

  12. Adherence and experimental infection of bacteria associated with periodontal infections of young cattle in Brazil ("Cara inchada"

    Directory of Open Access Journals (Sweden)

    Grassmann Barbara

    1997-01-01

    Full Text Available In vitro- and in vivo-assays were conducted, to study the possible role of streptomycin- and actinomycin-producing soil actinomycetes for the pathogenesis of "Cara inchada" in cattle (CI. Adherence of Bacteroides spp. to epithelial cells of the bovine gingiva, known to be associated with the progressive lesions of CI, was significantly increased by the addition of streptomycin, actinomycin or antibiotic culture supernatants of the soil actinomycetes. Applications of these mixtures together with Actinomyces pyogenes to the marginal gingiva of the upper premolar teeth of about 1 month old Holstein Friesian calves did not lead to progressive lesions of CI. Only one calf exhibited a slight diarrhea and a temporary retraction of the gingiva at the site of application.

  13. Transmissible microbial and metabolomic remodeling by soluble dietary fiber improves metabolic homeostasis.

    Science.gov (United States)

    He, Baokun; Nohara, Kazunari; Ajami, Nadim J; Michalek, Ryan D; Tian, Xiangjun; Wong, Matthew; Losee-Olson, Susan H; Petrosino, Joseph F; Yoo, Seung-Hee; Shimomura, Kazuhiro; Chen, Zheng

    2015-06-04

    Dietary fibers are increasingly appreciated as beneficial nutritional components. However, a requisite role of gut microbiota in fiber function and the overall impact of fibers on metabolomic flux remain unclear. We herein showed enhancing effects of a soluble resistant maltodextrin (RM) on glucose homeostasis in mouse metabolic disease models. Remarkably, fecal microbiota transplantation (FMT) caused pronounced and time-dependent improvement in glucose tolerance in RM recipient mice, indicating a causal relationship between microbial remodeling and metabolic efficacy. Microbial 16S sequencing revealed transmissible taxonomic changes correlated with improved metabolism, notably enrichment of probiotics and reduction of Alistipes and Bacteroides known to associate with high fat/protein diets. Metabolomic profiling further illustrated broad changes, including enrichment of phenylpropionates and decreases in key intermediates of glucose utilization, cholesterol biosynthesis and amino acid fermentation. These studies elucidate beneficial roles of RM-dependent microbial remodeling in metabolic homeostasis, and showcase prevalent health-promoting potentials of dietary fibers.

  14. The effect of microbial colonization on the host proteome varies by gastrointestinal location.

    Science.gov (United States)

    Lichtman, Joshua S; Alsentzer, Emily; Jaffe, Mia; Sprockett, Daniel; Masutani, Evan; Ikwa, Elvis; Fragiadakis, Gabriela K; Clifford, David; Huang, Bevan Emma; Sonnenburg, Justin L; Huang, Kerwyn Casey; Elias, Joshua E

    2016-05-01

    Endogenous intestinal microbiota have wide-ranging and largely uncharacterized effects on host physiology. Here, we used reverse-phase liquid chromatography-coupled tandem mass spectrometry to define the mouse intestinal proteome in the stomach, jejunum, ileum, cecum and proximal colon under three colonization states: germ-free (GF), monocolonized with Bacteroides thetaiotaomicron and conventionally raised (CR). Our analysis revealed distinct proteomic abundance profiles along the gastrointestinal (GI) tract. Unsupervised clustering showed that host protein abundance primarily depended on GI location rather than colonization state and specific proteins and functions that defined these locations were identified by random forest classifications. K-means clustering of protein abundance across locations revealed substantial differences in host protein production between CR mice relative to GF and monocolonized mice. Finally, comparison with fecal proteomic data sets suggested that the identities of stool proteins are not biased to any region of the GI tract, but are substantially impacted by the microbiota in the distal colon.

  15. Activity of endodontic antibacterial agents against selected anaerobic bacteria

    Directory of Open Access Journals (Sweden)

    Ferreira Cláudio Maniglia

    2002-01-01

    Full Text Available The antimicrobial activity of substances used as antibacterial agents (solutions of 10% calcium hydroxide, camphorated paramonochlorophenol - PMCC, 2% chlorhexidine digluconate and 10% castor oil plant detergent on anaerobic bacteria (Fusobacterium nucleatum ATCC 25586, Prevotella nigrescens ATCC 33563, Clostridium perfringens ATCC 13124 and Bacteroides fragilis ATCC 25285, using a broth dilution technique, was evaluated in vitro. For determination of minimum inhibitory and minimum bactericide concentrations (MIC and MBC, two culture broths, Reinforced Clostridial Medium (RCM and supplemented Brucella, standardized inoculum and serially diluted solutions were used. All antibacterial agents presented antimicrobial activity that varied for different bacteria. There were no differences in the performance of the two broths. Chlorhexidine digluconate was the most effective, with the lowest MICs, followed by castor oil detergent, PMCC and calcium hydroxide. C. perfringens and B. fragilis were the most resistant bacteria to all agents.

  16. Human gut microbes impact host serum metabolome and insulin sensitivity.

    Science.gov (United States)

    Pedersen, Helle Krogh; Gudmundsdottir, Valborg; Nielsen, Henrik Bjørn; Hyotylainen, Tuulia; Nielsen, Trine; Jensen, Benjamin A H; Forslund, Kristoffer; Hildebrand, Falk; Prifti, Edi; Falony, Gwen; Le Chatelier, Emmanuelle; Levenez, Florence; Doré, Joel; Mattila, Ismo; Plichta, Damian R; Pöhö, Päivi; Hellgren, Lars I; Arumugam, Manimozhiyan; Sunagawa, Shinichi; Vieira-Silva, Sara; Jørgensen, Torben; Holm, Jacob Bak; Trošt, Kajetan; Kristiansen, Karsten; Brix, Susanne; Raes, Jeroen; Wang, Jun; Hansen, Torben; Bork, Peer; Brunak, Søren; Oresic, Matej; Ehrlich, S Dusko; Pedersen, Oluf

    2016-07-21

    Insulin resistance is a forerunner state of ischaemic cardiovascular disease and type 2 diabetes. Here we show how the human gut microbiome impacts the serum metabolome and associates with insulin resistance in 277 non-diabetic Danish individuals. The serum metabolome of insulin-resistant individuals is characterized by increased levels of branched-chain amino acids (BCAAs), which correlate with a gut microbiome that has an enriched biosynthetic potential for BCAAs and is deprived of genes encoding bacterial inward transporters for these amino acids. Prevotella copri and Bacteroides vulgatus are identified as the main species driving the association between biosynthesis of BCAAs and insulin resistance, and in mice we demonstrate that P. copri can induce insulin resistance, aggravate glucose intolerance and augment circulating levels of BCAAs. Our findings suggest that microbial targets may have the potential to diminish insulin resistance and reduce the incidence of common metabolic and cardiovascular disorders.

  17. Microbiote intestinal et lipides : impact sur la santé humaine

    Directory of Open Access Journals (Sweden)

    Gérard Philippe

    2012-07-01

    Full Text Available The human intestine harbours a complex and diverse bacterial community called the gut microbiota. This microbiota, stable during the lifetime, is specific of each individual despite the existence of a phylogenetic core shared by the majority of adults. The influence of the gut microbiota on host’s physiology has been largely studied using germfree animals and recently it has been proposed that the gut microbiota affects nutrient acquisition, energy regulation and fat storage. Indeed, germfree animals are resistant to diet induced obesity and display low levels of blood and liver lipids. In humans, several grams of lipids reach the colon each day. These lipids have an impact on the gut microbiota composition characterized by an increase of the Firmicutes/ Bacteroides ratio. Concurrently, the gut microbiota is able to convert lipids, including fatty acids or cholesterol, leading to the production of metabolites with potential health effects.

  18. Bacterial ecology of abattoir wastewater treated by an anaerobic digestor.

    Science.gov (United States)

    Jabari, Linda; Gannoun, Hana; Khelifi, Eltaief; Cayol, Jean-Luc; Godon, Jean-Jacques; Hamdi, Moktar; Fardeau, Marie-Laure

    2016-01-01

    Wastewater from an anaerobic treatment plant at a slaughterhouse was analysed to determine the bacterial biodiversity present. Molecular analysis of the anaerobic sludge obtained from the treatment plant showed significant diversity, as 27 different phyla were identified. Firmicutes, Proteobacteria, Bacteroidetes, Thermotogae, Euryarchaeota (methanogens), and msbl6 (candidate division) were the dominant phyla of the anaerobic treatment plant and represented 21.7%, 18.5%, 11.5%, 9.4%, 8.9%, and 8.8% of the total bacteria identified, respectively. The dominant bacteria isolated were Clostridium, Bacteroides, Desulfobulbus, Desulfomicrobium, Desulfovibrio and Desulfotomaculum. Our results revealed the presence of new species, genera and families of microorganisms. The most interesting strains were characterised. Three new bacteria involved in anaerobic digestion of abattoir wastewater were published. Copyright © 2015 Sociedade Brasileira de Microbiologia. Published by Elsevier Editora Ltda. All rights reserved.

  19. Bacterial ecology of abattoir wastewater treated by an anaerobic digestor

    Directory of Open Access Journals (Sweden)

    Linda Jabari

    2016-03-01

    Full Text Available Abstract Wastewater from an anaerobic treatment plant at a slaughterhouse was analysed to determine the bacterial biodiversity present. Molecular analysis of the anaerobic sludge obtained from the treatment plant showed significant diversity, as 27 different phyla were identified. Firmicutes, Proteobacteria, Bacteroidetes, Thermotogae, Euryarchaeota (methanogens, and msbl6 (candidate division were the dominant phyla of the anaerobic treatment plant and represented 21.7%, 18.5%, 11.5%, 9.4%, 8.9%, and 8.8% of the total bacteria identified, respectively. The dominant bacteria isolated were Clostridium, Bacteroides, Desulfobulbus, Desulfomicrobium, Desulfovibrio and Desulfotomaculum. Our results revealed the presence of new species, genera and families of microorganisms. The most interesting strains were characterised. Three new bacteria involved in anaerobic digestion of abattoir wastewater were published.

  20. Biomedical Applications of Fermenticin HV6b Isolated from Lactobacillus fermentum HV6b MTCC10770

    Directory of Open Access Journals (Sweden)

    Baljinder Kaur

    2013-01-01

    Full Text Available Fermenticin HV6b is a class IIa antimicrobial peptide produced by Lactobacillus fermentum HV6b MTCC 10770 isolated from human vaginal ecosystem. It shows growth inhibition of a wide range of opportunistic pathogens of humans, for example, Bacteroides, Gardnerella vaginalis, Mobiluncus, Staphylococci, and Streptococci, associated with bacterial vaginosis in humans. It does possess an impressive sperm immobilization and spermicidal activity tested against human sperms which makes it an attractive proposition for formulating antibacterial vaginosis and contraceptive products. Apart from this, in vitro studies conducted against four different tissue models have indicated its potential to be used as a component of anticancerous drug therapy as it is reported to induce apoptosis in cancerous cells. This information could be integrated in future studies focusing on in vivo assessment of anticancerous activity of lactic acid bacterial toxins or bacteriocins.

  1. Temporomandibular Joint Septic Arthritis and Mandibular Osteomyelitis Arising From an Odontogenic Infection: A Case Report and Review of the Literature.

    Science.gov (United States)

    Gams, Kevin; Freeman, Phillip

    2016-04-01

    Septic arthritis of the temporomandibular joint (TMJ) has been infrequently reported in the literature. Some investigators believe that this condition is under-reported because it is underdiagnosed. Misdiagnosis or late diagnosis of this condition can lead to serious morbidity, including fistula formation, intracranial abscess, fibrous or bony ankylosis, temporal bone or condylar osteomyelitis, growth alteration, and several others. This report describes a case of septic TMJ arthritis arising from direct spread of an odontogenic infection with subsequent development of mandibular osteomyelitis. The purpose of this case report is to 1) increase awareness of an underdiagnosed condition, 2) establish the seriousness of this infection, 3) for the first time report on a case of TMJ septic arthritis caused by Bacteroides infection, and 4) provide a review of the relevant literature. Copyright © 2016 American Association of Oral and Maxillofacial Surgeons. Published by Elsevier Inc. All rights reserved.

  2. Effects of bitter melon (Momordica charantia L.) on the gut microbiota in high fat diet and low dose streptozocin-induced rats.

    Science.gov (United States)

    Zhu, Ying; Bai, Juan; Zhang, Yi; Xiao, Xiang; Dong, Ying

    2016-09-01

    The effects on gut microbiota of type 2 diabetic rats fed a bitter melon formulation (BLSP, a lyophilized superfine powder) were investigated. BLSP treatment significantly reduced fasting blood glucose levels (p diabetic rats. The gut microbiota of treated and control rats were profiled by PCR amplification and pyrosequencing of 16S rRNA genes (V3-V9 region). BLSP significantly reduced the ratio of Firmicutes to Bacteroidetes in diabetic rats, while the relative abundances of Ruminococcaceae, Bacteroides and Ruminococcus were significantly lowered in BLSP-treated rats compared to diabetic rats. Additionally, BLSP significantly suppressed the activation of MAPK (JNK and p38). The results indicate that BLSP can significantly modify the proportions of particular gut microbiota in diabetic rats without disturbing the normal population diversity. By suppressing the activation of MAPK signaling pathway, a BLSP containing diet may ameliorate type 2 diabetes.

  3. ARE ENTEROCOCCUS FAECIUM CRL 183 AND LACTOBACILLUS HELVETICUS SSP. JUGURTI 416 ABLE TO PRODUCE ANTIMICROBIAL SUBSTANCE?

    Directory of Open Access Journals (Sweden)

    R. BEDANI

    2008-12-01

    Full Text Available

    Production of antimicrobial substance by E. faecium CRL 183 and L. helveticus ssp jugurti 416 was tested against pathogenic bacteria and microorganisms isolated from Wistar rat faeces, using a spot-on-the-lawn assay. Three pathogenic bacteria (Listeria monocytogenes 1/2a, Salmonella enteridites 193/95, Escherichia coli O157:H7 and twenty-fi ve colonies, isolated from animal faeces, belonging to the following groups Enterococcus, Lactobacillus, Clostridium, Bacteroides and Enterobacteriaceae, were used as indicator microorganisms. The results showed that E. faecium CRL 183 and L. helveticus ssp jugurti 416 did not produce signifi cant antimicrobial activity against the indicator microorganisms tested. More tests needed to be carried out with other indicator bacteria and other culture media to confi rm the lack of antimicrobial production.

  4. AcEST: BP916894 [AcEST

    Lifescience Database Archive (English)

    Full Text Available Ttn PE=1 SV=1 33 0.45 sp|Q5GN48|DMD_PIG Dystrophin OS=Sus scrofa GN=DMD PE=1 SV=1 33 0.45 sp|A6KYH1|RS4_BACV...8 30S ribosomal protein S4 OS=Bacteroides vulg... 33 0.58 sp|P11531|DMD_MOUSE Dystrophin OS=Mus musculus GN=...Dmd PE=1 SV=2 33 0.58 sp|P11532|DMD_HUMAN Dystrophin OS=Homo sapiens GN=DMD PE=1 ...APLKVPTAEKKVRKLLPEP 12730 >sp|Q5GN48|DMD_PIG Dystrophin OS=Sus scrofa GN=DMD PE=1...AKYTYGVLEKQFRNL 71 >sp|P11531|DMD_MOUSE Dystrophin OS=Mus musculus GN=Dmd PE=1 SV=2 Length = 3678 Score = 32

  5. Development and Validation of an Enzymatic Method To Determine Stevioside Content from Stevia rebaudiana.

    Science.gov (United States)

    Udompaisarn, Somsiri; Arthan, Dumrongkiet; Somana, Jamorn

    2017-04-19

    An enzymatic method for specific determination of stevioside content was established. Recombinant β-glucosidase BT_3567 (rBT_3567) from Bacteroides thetaiotaomicron HB-13 exhibited selective hydrolysis of stevioside at β-1,2-glycosidic bond to yield rubusoside and glucose. Coupling of this enzyme with glucose oxidase and peroxidase allowed for quantitation of stevioside content in Stevia samples by using a colorimetric-based approach. The series of reactions for stevioside determination can be completed within 1 h at 37 °C. Stevioside determination using the enzymatic assay strongly correlated with results obtained from HPLC quantitation (r 2 = 0.9629, n = 16). The percentages of coefficient variation (CV) of within day (n = 12) and between days (n = 12) assays were lower than 5%, and accuracy ranges were 95-105%. This analysis demonstrates that the enzymatic method developed in this study is specific, easy to perform, accurate, and yields reproducible results.

  6. Femoral vein thrombophlebitis and septic pulmonary embolism due to a mixed anaerobic infection including Solobacterium moorei: a case report

    Directory of Open Access Journals (Sweden)

    Martin Claire A

    2007-07-01

    Full Text Available Abstract Background Primary foci of necrobacillosis infection outside the head and neck are uncommon but have been reported in the urogenital or gastrointestinal tracts. Reports of infection with Solobacterium moorei are rare. Case presentation A 37-year-old male intravenous drug user was admitted with pain in his right groin, fever, rigors and vomiting following a recent injection into the right femoral vein. Admission blood cultures grew Fusobacterium nucleatum, Solobacterium moorei and Bacteroides ureolyticus. The patient was successfully treated with intravenous penicillin and metronidazole. Conclusion This case report describes an unusual case of femoral thrombophlebitis with septic pulmonary embolism associated with anaerobic organisms in a groin abscess. Solobacterium moorei, though rarely described, may also have clinically significant pathogenic potential.

  7. The effect of whole-grain compared to refined wheat on the gut microbial composition and integrity in a colonic epithelial cell model following a 12-week energy-restricted dietary intervention in postmenopausal women

    DEFF Research Database (Denmark)

    Christensen, Ellen Gerd; Licht, Tine Rask; Kristensen, M.

    as the Enterobacteriaceae family. Potential bifidogenic effects were examined in depth by determining the levels of B. bifidum, B. adolescentis, B. catenulatum, and B. longum. The ratios of both Bifidobacteria and Lactobacillus increased following the WW intervention. The composition of the gut microbiota may affect......Intake of whole-grain products are considered to decrease the risk of cardiovascular disease (CVD). This effect could potentially be linked to a prebiotic effect, hence positive modulation of the gut microbial composition or activity. Kristensen and coworkers recently conducted a study...... groups (Kristensen, et al, 2012). We used fecal samples from the same study to examine effects of WW and RW on the bacterial composition by quantitative PCR targeting the phylums Bacteroidetes and Firmicutes, and the genera Bifidobacteria, Lactobacillus, Bacteroides, and Prevotella, as well...

  8. Identification of ceramide phosphorylethanolamine and ceramide phosphorylglycerol in the lipids of an anaerobic bacterium.

    Science.gov (United States)

    LaBach, J P; White, D C

    1969-09-01

    Nearly half the phospholipids isolated from the anerobic bacterium Bacteroides melaninogenicus are phosphosphingolipids. The two major phosphosphingolipids have been characterized as ceramide phosphorylethanolamine and ceramide phosphorylglycerol. The long-chain bases of these phosphosphingolipids appear to have branched and normal saturated carbon chains of 17, 18, and 19 atoms; the phosphate is at the 1-position of the long-chain base. The composition of the amide-linked fatty acids of the phosphosphingolipids differs from that of the ester-linked fatty acids of the diacylphosphoglycerides in having a higher percentage of 14:0, 17:0, and 18:0 acids as well as containing nearly all the monoenoic fatty acids found in the bacterial lipids. The finding of phosphosphingolipids in bacteria is exceedingly rare and to our knowledge ceramide phosphorylglycerol has not been previously found in nature.

  9. Effects of feeding potato pulp on cholesterol metabolism and its association with cecal conditions in rats.

    Science.gov (United States)

    Hashimoto, Naoto; Nakamura, Yumi; Noda, Takahiro; Han, Kyu-Ho; Fukushima, Michihiro

    2011-11-01

    To clarify the functional properties of potato pulp (PP), a waste product resulting from extraction of starch from potatoes, we examined the effects of PP on cholesterol metabolism and cecal conditions in rats. Plasma total cholesterol (T-Chol) levels were lower in rats fed a PP-supplemented diet for four weeks than in those fed a control diet. Cecal pH was lowered due to an increase in the levels of cecal total short-chain fatty acids, especially butyrate, in the PP group compared to the control group. Furthermore, animals fed with the PP-supplemented diet showed increased cecal ratios of Lactobacillus and Clostridia and decreased cecal ratios of Bacteroides and Gammaproteobacteria with slightly negative and positive correlations with plasma T-Chol levels, respectively. In conclusion, ingestion of PP for four weeks is likely to improve both cecal conditions and cholesterol metabolism, suggesting that PP has prebiotic effects.

  10. Dicty_cDB: Contig-U16580-1 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available d:none) Entamoeba histolytica 30 kDa type I co... 94 2e-17 AB282671_1( AB282671 |pid:none) Entamoeba nutt...e) Bacteroides fragilis YCH46 DNA,... 93 3e-17 AB282667_1( AB282667 |pid:none) Entamoeba nuttalli prx-1 gene... for ... 93 4e-17 AB282668_1( AB282668 |pid:none) Entamoeba nuttalli prx-2 gene f...or ... 93 4e-17 AB282673_1( AB282673 |pid:none) Entamoeba nuttalli prx-7 gene for ... 93 4e-17 AB282672_1( A...B282672 |pid:none) Entamoeba nuttalli prx-6 gene for ... 93 4e-17 ( P19476 ) RecName: Full=Putative peroxire

  11. Garlic derivatives (PTS and PTS-O) differently affect the ecology of swine faecal microbiota in vitro.

    Science.gov (United States)

    Ruiz, Raquel; García, M P; Lara, A; Rubio, L A

    2010-07-29

    A number of in vitro experiments were designed to evaluate the effects of two different industrial products, namely PROALLIUM-S-DMC and PROALLIUM-SO-DMC (DMC Research Center, Granada, Spain), obtained from garlic (Allium sativum) on the faecal microbiota of pigs. The effects of three different concentrations (50, 200 and 400 ppm) of the active compounds (PTS and PTS-O, respectively) from both industrial products on the gastrointestinal microbiota of pigs were tested. Growth medium without any additive (0 ppm) was used as control. Predominant bacterial groups (total aerobes, total anaerobes, lactobacilli, bifidobacteria, coliforms, enterobacteria, bacteroides and clostridia) were studied. Results showed that both PTS and PTS-O have significant (Pantibiotics in pig feeds. Copyright (c) 2009 Elsevier B.V. All rights reserved.

  12. Use of chemotaxonomy as an aid to differentiate among Capnocytophaga species, CDC group DF-3, and aerotolerant strains of Leptotrichia buccalis.

    Science.gov (United States)

    Bernard, K; Cooper, C; Tessier, S; Ewan, E P

    1991-01-01

    Four strains of fastidious gram-negative rods, thought to be Capnocytophaga species (formerly CDC group DF-1 or Bacteroides ochraceus) or CDC group DF-3 on the basis of conventional phenotypic criteria, were also analyzed for cellular fatty acid (CFA) composition. It was found that the CFA compositions of these strains were qualitatively incorrect for those taxa. Subsequently, it was determined that all four bacteria were in fact aerotolerant strains of Leptotrichia buccalis, based on biochemical reactions, CFA composition, and lactic acid as the major end product of glucose fermentation. It is recommended that, in addition to conventional cultural and biochemical criteria, all strains of Capnocytophaga or CDC group DF-3 should also be tested for metabolic end products of fermentation and CFA composition as essential adjuncts for identification. PMID:1939582

  13. Characterization of microbial community in the leachate associated with the decomposition of entombed pigs.

    Science.gov (United States)

    Yang, Seung-Hak; Hong, Sun Hwa; Cho, Sung Back; Lim, Joung Soo; Bae, Sung Eun; Ahn, Heekwon; Lee, Eun Young

    2012-10-01

    Foot and mouth disease (FMD) is one of the acute infectious diseases in hoofed and even-toed mammals, including pigs, and it occurs via acute infection by Aphthovirus. When FMD is suspected, animals around the location of origin are typically slaughtered and buried. Other methods such as rendering, composting, and incineration have not been verified in practice in Korea. After the FMD incident, the regular monitoring of the microbial community is required, as microorganisms greatly modify the characteristics of the ecosystem in which they live. This is the result of their metabolic activities causing chemical changes to take place in the surrounding environment. In this study, we investigated changes in the microbial community during a 24 week period with DNA extracts from leachate, formed by the decomposition of buried pigs at a laboratory test site, using denaturing gradient gel electrophoresis (DGGE) with a genomic DNA. Our results revealed that Bacteroides coprosuis, which is common in pig excreta, and Sporanaerobacter acetigenes, which is a sulfur-reduced microbe, were continuously observed. During the early stages (0~2 weeks) of tissue decomposition, Clostridium cochlearium, Fusobacterium ulcerans, and Fusobacterium sp., which are involved in skin decomposition, were also observed. In addition, various microbes such as Turicibacter sanguinis, Clostridium haemolyticum, Bacteroides propionicifaciens, and Comamonas sp. were seen during the later stages (16~24 weeks). In particular, the number of existing microbial species gradually increased during the early stages, including the exponential phase, decreased during the middle stages, and then increased again during the later stages. Therefore, these results indicate that the decomposition of pigs continues for a long period of time and leachate is created continuously during this process. It is known that leachate can easily flow into the neighboring environment, so a long-term management plan is needed in

  14. Avaliação das atividades antibacteriana, tripanocida e citotóxica do extrato hidroalcóolico das raízes de Tradescantia sillamontana Matuda (Veludo Branco (Commelinaceae

    Directory of Open Access Journals (Sweden)

    E.B.B. ESTEVAM

    Full Text Available RESUMO O objetivo deste estudo foi avaliar o efeito antibacteriano e tripanocida in vitro do extrato hidroalcóolico das raízes de Tradescantia sillamontana Matuda (Commelinaceae, conhecida popularmente como veludo branco. Foi avaliada a atividade antibacteriana in vitro frente às bactérias Streptococcus mitis (CIM = 100 µg/mL; CMB = 150 µg/mL, Streptococcus mutans (CIM = 200 µg/mL; CMB = 220 µg/mL, Streptococcus sanguinis (CIM = 400 µg/mL; CMB = 425 µg/mL, Streptococcus sobrinus (CIM = 400 µg/mL; CMB = 420 µg/mL e Bacteroides fragilis (CIM = 400 µg/mL; CMB = 430 µg/mL pelo método de diluição em caldo. Os protozoários da família tripanossomatídeo causam doenças tropicais que costumam ser negligenciadas que costumam ser como a tripanossomíase, para a qual estão disponíveis poucos medicamentos. Neste contexto, o extrato hidroalcóolico das raízes de T. sillamontana também foi avaliado frente às formas tripomastigotas da cepa Y de Trypanosoma cruzi, com promissora atividade frente a este protozoário (IC50 = 2,4 µg/mL. Quando avaliada a atividade citotóxica frente a fibroblastos da linhagem LLCMK2, o extrato apresentou moderada citotoxicidade (CC50 = 480,37 µg/mL. Os resultados ora apresentados para o extrato hidroalcóolico das raízes de Tradescantia sillamontana Matuda demonstraram promissoras atividades antibacteriana e tripanocida, sendo uma fonte alternativa de produtos naturais com atividades contra T. cruzi e algumas bactérias do gênero Streptococcus e Bacteroides.

  15. Quantification of human-associated fecal indicators reveal sewage from urban watersheds as a source of pollution to Lake Michigan

    Science.gov (United States)

    Olds, Hayley T.; Dila, Deborah K.; Bootsma, Melinda J.; Corsi, Steven; McLellan, Sandra L.

    2016-01-01

    Sewage contamination of urban waterways from sewer overflows and failing infrastructure is a major environmental and public health concern. Fecal coliforms (FC) are commonly employed as fecal indicator bacteria, but do not distinguish between human and non-human sources of fecal contamination. Human Bacteroides and humanLachnospiraceae, two genetic markers for human-associated indicator bacteria, were used to identify sewage signals in two urban rivers and the estuary that drains to Lake Michigan. Grab samples were collected from the rivers throughout 2012 and 2013 and hourly samples were collected in the estuary across the hydrograph during summer 2013. Human Bacteroides and human Lachnospiraceae were highly correlated with each other in river samples (Pearson’s r = 0.86), with average concentrations at most sites elevated during wet weather. These human indicators were found during baseflow, indicating that sewage contamination is chronic in these waterways. FC are used for determining total maximum daily loads (TMDLs) in management plans; however, FC concentrations alone failed to prioritize river reaches with potential health risks. While 84% of samples with >1000 CFU/100 ml FC had sewage contamination, 52% of samples with moderate (200–1000 CFU/100 ml) and 46% of samples with low (<200 CFU/100 ml) FC levels also had evidence of human sewage. Load calculations in the in the Milwaukee estuary revealed storm-driven sewage contamination varied greatly among events and was highest during an event with a short duration of intense rain. This work demonstrates urban areas have unrecognized sewage inputs that may not be adequately prioritized for remediation by the TMDL process. Further analysis using these approaches could determine relationships between land use, storm characteristics, and other factors that drive sewage contamination in urban waterways.

  16. An ABC-Type Cobalt Transport System Is Essential for Growth of Sinorhizobium melilotiat Trace Metal Concentrations ▿ †

    Science.gov (United States)

    Cheng, Jiujun; Poduska, Branislava; Morton, Richard A.; Finan, Turlough M.

    2011-01-01

    We report expression and mutant phenotypes for a gene cluster in Sinorhizobium meliloti, designated cbtJKL, that has been shown to encode an ABC-type cobalt transport system. Transcription of cbtJKLinitiated 384 nucleotides upstream from the cbtJtranslation start codon, and the resulting 5′ region contained a putative B12riboswitch. Expression of the cbtJKLgenes appeared to be controlled by (cobalt-loaded) cobalamin interacting at the B12riboswitch, since (i) a putative B12riboswitch was located within this large upstream region, (ii) cbtJtranscription was repressed upon addition of cobalt or vitamin B12, and (iii) deletions in the B12riboswitch resulted in constitutive cbtJKLtranscription. Insertion mutants in cbtJKLfailed to grow in LB medium, and growth was restored through the addition of cobalt but not other metals. This growth phenotype appeared to be due to the chelation of cobalt present in LB, and cbtJKLmutants also failed to grow in minimal medium containing the chelating agent EDTA unless the medium was supplemented with additional or excess cobalt. In uptake experiments, 57Co2+accumulation was high in wild-type cells expressing the cbtJKLgenes, whereas wild-type cells in which cbtJKLexpression was repressed showed reduced accumulation. In cbtJKLmutant cells, 57Co2+accumulation was reduced relative to that of the wild type, and presumably, this residual cobalt transport occurred via an alternate ion uptake system(s) that is not specific to cobalt. In symbiosis, the alternate system(s) appeared to mediate cobalt transport into bacteroid cells, as low cbtJKLexpression was detected in bacteroids and cbtJKLmutants formed N2-fixing nodules on alfalfa. PMID:21725018

  17. Effects of the Dietary Protein and Carbohydrate Ratio on Gut Microbiomes in Dogs of Different Body Conditions

    Directory of Open Access Journals (Sweden)

    Qinghong Li

    2017-01-01

    Full Text Available Obesity has become a health epidemic in both humans and pets. A dysbiotic gut microbiota has been associated with obesity and other metabolic disorders. High-protein, low-carbohydrate (HPLC diets have been recommended for body weight loss, but little is known about their effects on the canine gut microbiome. Sixty-three obese and lean Labrador retrievers and Beagles (mean age, 5.72 years were fed a common baseline diet for 4 weeks in phase 1, followed by 4 weeks of a treatment diet, specifically, the HPLC diet (49.4% protein, 10.9% carbohydrate or a low-protein, high-carbohydrate (LPHC diet (25.5% protein, 38.8% carbohydrate in phase 2. 16S rRNA gene profiling revealed that dietary protein and carbohydrate ratios have significant impacts on gut microbial compositions. This effect appeared to be more evident in obese dogs than in lean dogs but was independent of breed. Consumption of either diet increased the bacterial evenness, but not the richness, of the gut compared to that after consumption of the baseline diet. Macronutrient composition affected taxon abundances, mainly within the predominant phyla, Firmicutes and Bacteroidetes. The LPHC diet appeared to favor the growth of Bacteroides uniformis and Clostridium butyricum, while the HPLC diet increased the abundances of Clostridium hiranonis, Clostridium perfringens, and Ruminococcus gnavus and enriched microbial gene networks associated with weight maintenance. In addition, we observed a decrease in the Bacteroidetes to Firmicutes ratio and an increase in the Bacteroides to Prevotella ratio in the HPLC diet-fed dogs compared to these ratios in dogs fed other diets. Finally, analysis of the effect of diet on the predicted microbial gene network was performed using phylogenetic investigation of communities by reconstruction of unobserved states (PICRUSt.

  18. Sulfate-reducing bacteria colonize pouches formed for ulcerative colitis but not for familial adenomatous polyposis.

    LENUS (Irish Health Repository)

    Duffy, M

    2012-02-03

    PURPOSE: Ileal pouch-anal anastomosis remains the "gold standard" in surgical treatment of ulcerative colitis and familial adenomatous polyposis. Pouchitis occurs mainly in patients with a background of ulcerative colitis, although the reasons for this are unknown. The aim of this study was to characterize differences in pouch bacterial populations between ulcerative colitis and familial adenomatous pouches. METHODS: After ethical approval was obtained, fresh stool samples were collected from patients with ulcerative colitis pouches (n = 10), familial adenomatous polyposis (n = 7) pouches, and ulcerative colitis ileostomies (n = 8). Quantitative measurements of aerobic and anaerobic bacteria were performed. RESULTS: Sulfate-reducing bacteria were isolated from 80 percent (n = 8) of ulcerative colitis pouches. Sulfate-reducing bacteria were absent from familial adenomatous polyposis pouches and also from ulcerative colitis ileostomy effluent. Pouch Lactobacilli, Bifidobacterium, Bacteroides sp, and Clostridium perfringens counts were increased relative to ileostomy counts in patients with ulcerative colitis. Total pouch enterococci and coliform counts were also increased relative to ileostomy levels. There were no significant quantitative or qualitative differences between pouch types when these bacteria were evaluated. CONCLUSIONS: Sulfate-reducing bacteria are exclusive to patients with a background of ulcerative colitis. Not all ulcerative colitis pouches harbor sulfate-reducing bacteria because two ulcerative colitis pouches in this study were free of the latter. They are not present in familial adenomatous polyposis pouches or in ileostomy effluent collected from patients with ulcerative colitis. Total bacterial counts increase in ulcerative colitis pouches after stoma closure. Levels of Lactobacilli, Bifidobacterium, Bacteroides sp, Clostridium perfringens, enterococci, and coliforms were similar in both pouch groups. Because sulfate-reducing bacteria are

  19. Fish oil enhances recovery of intestinal microbiota and epithelial integrity in chronic rejection of intestinal transplant.

    Directory of Open Access Journals (Sweden)

    Qiurong Li

    Full Text Available BACKGROUND: The intestinal chronic rejection (CR is the major limitation to long-term survival of transplanted organs. This study aimed to investigate the interaction between intestinal microbiota and epithelial integrity in chronic rejection of intestinal transplantation, and to find out whether fish oil enhances recovery of intestinal microbiota and epithelial integrity. METHODS/PRINCIPAL FINDINGS: The luminal and mucosal microbiota composition of CR rats were characterized by DGGE analysis at 190 days after intestinal transplant. The specific bacterial species were determined by sequence analysis. Furthermore, changes in the localization of intestinal TJ proteins were examined by immunofluorescent staining. PCR-DGGE analysis revealed that gut microbiota in CR rats had a shift towards Escherichia coli, Bacteroides spp and Clostridium spp and a decrease in the abundance of Lactobacillales bacteria in the intestines. Fish oil supplementation could enhance the recovery of gut microbiota, showing a significant decrease of gut bacterial proportions of E. coli and Bacteroides spp and an increase of Lactobacillales spp. In addition, CR rats showed pronounced alteration of tight junction, depicted by marked changes in epithelial cell ultrastructure and redistribution of occuldin and claudins as well as disruption in TJ barrier function. Fish oil administration ameliorated disruption of epithelial integrity in CR, which was associated with an improvement of the mucosal structure leading to improved tight junctions. CONCLUSIONS/SIGNIFICANCE: Our study have presented novel evidence that fish oil is involved in the maintenance of epithelial TJ integrity and recovery of gut microbiota, which may have therapeutic potential against CR in intestinal transplantation.

  20. [The duodenal microbiota composition in children with active coeliac disease is influenced by the degree of enteropathy].

    Science.gov (United States)

    Girón Fernández-Crehuet, F; Tapia-Paniagua, S; Moriñigo Gutiérrez, M A; Navas-López, V M; Juliana Serrano, M; Blasco-Alonso, J; Sierra Salinas, C

    2016-04-01

    To establish whether the duodenal mucosa microbiota of children with active coeliac disease (CD) and healthy controls (HC) differ in composition and biodiversity. Samples of duodenal biopsies in 11 CD patients were obtained at diagnosis, and in 6 HC who were investigated for functional intestinal disorders of non-CD origin. Total duodenal microbiota and the belonging to the genus Lactobacillus using PCR-denaturing gradient gel electrophoresis (DGGE) were analysed. The banding patterns obtained in the resulting gels were analysed to determine the differences between the microbiota of CD patients and HC (FPQuest 4.5) while environmental indexes (richness, diversity and habitability) were calculated with the Past version 2.17 program. The intestinal microbiota of patients with Marsh 3c lesion showed similarity of 98% and differs from other CD patients with other type of histologic lesion as Marsh3a, Marsh3b and Marsh2. The main differences were obtained in ecological indexes belonging to the genus Lactobacillus, with significant richness, diversity and habitability reduction in CD patients. In CD bands were categorized primarily with Streptococcus, Bacteroides and E.coli species. In HC the predominant bands were Bifidobacterium, Lactobacillus and Acinetobacter, though the Streptococcus and Bacteroides were lower. The celiac patients with major histological affectation presented a similar microbiota duodenal. The ecological indexes applied to the genus Lactobacillus were significantly reduced in CD. Copyright © 2015 Asociación Española de Pediatría. Published by Elsevier España, S.L.U. All rights reserved.

  1. Fecal menaquinone profiles of overweight adults are associated with gut microbiota composition during a gut microbiota-targeted dietary intervention.

    Science.gov (United States)

    Karl, J Philip; Fu, Xueyan; Wang, Xiaoxin; Zhao, Yufeng; Shen, Jian; Zhang, Chenhong; Wolfe, Benjamin E; Saltzman, Edward; Zhao, Liping; Booth, Sarah L

    2015-07-01

    Emerging evidence supports novel roles for vitamin K in cardiometabolic health, some of which may be unique to the bacterially synthesized vitamin K forms known as menaquinones. However, factors influencing menaquinone biosynthesis by the gut microbiota and associations with cardiometabolic health have not been examined. The objective of this study was to identify associations between fecal menaquinone profiles, gut microbiota composition, and biomarkers of cardiometabolic health. The menaquinone profile and gut microbiota structure were periodically measured in fecal samples collected from 77 overweight Chinese adults who consumed a prescribed diet previously shown to alter gut microbiota composition and to improve cardiometabolic biomarkers. Covariance among menaquinones within individual fecal samples partitioned individuals into 2 distinct groups, herein introduced as menaquinotypes of the human gut. Menaquinotypes were characterized by differences in menaquinone (MK) 5 and MK9-MK13 and differences in the relative abundance of several operational taxonomic units (OTUs) delineated at the species level, predominantly within the genera Prevotella spp. and Bacteroides spp. Fecal MK4, MK6, and MK8 decreased during the intervention (P 100 OTUs were associated with altered fecal content of ≥1 individual menaquinone. The strongest and most consistent relations were between Prevotella spp. and MK5 and MK11-MK13, between Bacteroides spp. and MK9 and MK10, and between Escherichia/Shigella spp. and MK8. Neither individual menaquinones nor menaquinotypes were longitudinally associated with markers of glycemia, insulin resistance, or inflammation. These findings suggest that variability in fecal menaquinone content is predominantly determined by relatively few genera within the gut microbiota and that diet-mediated alterations in gut microbiota composition may provide a feasible approach for altering gut menaquinone content. This trial was registered at the Chinese

  2. Balancing Herbal Medicine and Functional Food for Prevention and Treatment of Cardiometabolic Diseases through Modulating Gut Microbiota

    Science.gov (United States)

    Lyu, Ming; Wang, Yue-fei; Fan, Guan-wei; Wang, Xiao-ying; Xu, Shuang-yong; Zhu, Yan

    2017-01-01

    It has become apparent that gut microbiota is closely associated with cardiometabolic diseases (CMDs), and alteration in microbiome compositions is also linked to the host environment. Next generation sequencing (NGS) has facilitated in-depth studies on the effects of herbal medicine and functional food on gut microbiota. Both herbal medicine and functional food contain fiber, polyphenols and polysaccharides, exerting prebiotics-like activities in the prevention and treatment of CMDs. The administrations of herbal medicine and functional food lead to increased the abundance of phylum Bacteroidetes, and genus Akkermansia, Bifidobacteria, Lactobacillus, Bacteroides and Prevotella, while reducing phylum Firmicutes and Firmicutes/Bacteroidetes ratio in gut. Both herbal medicine and functional food interact with gut microbiome and alter the microbial metabolites including short-chain fatty acids (SCFAs), bile acids (BAs) and lipopolysaccharides (LPS), which are now correlated with metabolic diseases such as type 2 diabetes (T2D), obesity and non-alcoholic fatty liver disease (NAFLD). In addition, trimethylamine (TMA)-N-oxide (TMAO) is recently linked to atherosclerosis (AS) and cardiovascular disease (CVD) risks. Moreover, gut-organs axes may serve as the potential strategy for treating CMDs with the intervention of herbal medicine and functional food. In summary, a balance between herbal medicine and functional food rich in fiber, polyphenols and polysaccharides plays a vital role in modulating gut microbiota (phylum Bacteroidetes, Firmicutes and Firmicutes/Bacteroidetes ratio, and genus Akkermansia, Bifidobacteria, Lactobacillus, Bacteroides and Prevotella) through SCFAs, BAs, LPS and TMAO signaling regarding CMDs. Targeting gut-organs axes may serve as a new therapeutic strategy for CMDs by herbal medicine and functional food in the future. This review aims to summarize the balance between herbal medicine and functional food utilized for the prevention and treatment

  3. Natural history of the infant gut microbiome and impact of antibiotic treatment on bacterial strain diversity and stability.

    Science.gov (United States)

    Yassour, Moran; Vatanen, Tommi; Siljander, Heli; Hämäläinen, Anu-Maaria; Härkönen, Taina; Ryhänen, Samppa J; Franzosa, Eric A; Vlamakis, Hera; Huttenhower, Curtis; Gevers, Dirk; Lander, Eric S; Knip, Mikael; Xavier, Ramnik J

    2016-06-15

    The gut microbial community is dynamic during the first 3 years of life, before stabilizing to an adult-like state. However, little is known about the impact of environmental factors on the developing human gut microbiome. We report a longitudinal study of the gut microbiome based on DNA sequence analysis of monthly stool samples and clinical information from 39 children, about half of whom received multiple courses of antibiotics during the first 3 years of life. Whereas the gut microbiome of most children born by vaginal delivery was dominated by Bacteroides species, the four children born by cesarean section and about 20% of vaginally born children lacked Bacteroides in the first 6 to 18 months of life. Longitudinal sampling, coupled with whole-genome shotgun sequencing, allowed detection of strain-level variation as well as the abundance of antibiotic resistance genes. The microbiota of antibiotic-treated children was less diverse in terms of both bacterial species and strains, with some species often dominated by single strains. In addition, we observed short-term composition changes between consecutive samples from children treated with antibiotics. Antibiotic resistance genes carried on microbial chromosomes showed a peak in abundance after antibiotic treatment followed by a sharp decline, whereas some genes carried on mobile elements persisted longer after antibiotic therapy ended. Our results highlight the value of high-density longitudinal sampling studies with high-resolution strain profiling for studying the establishment and response to perturbation of the infant gut microbiome. Copyright © 2016, American Association for the Advancement of Science.

  4. Thiol-based redox signaling in the nitrogen-fixing symbiosis

    Directory of Open Access Journals (Sweden)

    Pierre eFrendo

    2013-09-01

    Full Text Available In nitrogen poor soils legumes establish a symbiotic interaction with rhizobia that results in the formation of root nodules. These are unique plant organs where bacteria differentiate into bacteroids, which express the nitrogenase enzyme complex that reduces atmospheric N2 to ammonia. Nodule metabolism requires a tight control of the concentrations of reactive oxygen and nitrogen species (RONS so that they can perform useful signaling roles while avoiding nitro-oxidative damage. In nodules a thiol-dependent regulatory network that senses, transmits and responds to redox changes is starting to be elucidated. A combination of enzymatic, immunological, pharmacological and molecular analyses has allowed to conclude that glutathione and its legume-specific homolog, homoglutathione, are abundant in meristematic and infected cells, their spatio-temporally distribution is correlated with the corresponding (homoglutathione synthetase activities, and are crucial for nodule development and function. Glutathione is at high concentrations in the bacteroids and at moderate amounts in the mitochondria, cytosol and nuclei. Less information is available on other components of the network. The expression of multiple isoforms of glutathione peroxidases, peroxiredoxins, thioredoxins, glutaredoxins and NADPH-thioredoxin reductases has been detected in nodule cells using antibodies and proteomics. Peroxiredoxins and thioredoxins are essential to regulate and in some cases to detoxify RONS in nodules. Further research is necessary to clarify the regulation of the expression and activity of thiol redox-active proteins in response to abiotic, biotic and developmental cues, their interactions with downstream targets by disulfide-exchange reactions, and their participation in signaling cascades. The availability of mutants and transgenic lines will be crucial to facilitate systematic investigations into the function of the various proteins in the legume

  5. Orbital abscess bacterial isolates and in vitro antimicrobial susceptibility patterns in dogs and cats.

    Science.gov (United States)

    Wang, Annie L; Ledbetter, Eric C; Kern, Thomas J

    2009-01-01

    To determine bacterial populations, in vitro antimicrobial susceptibility patterns, and sources of microorganisms for dogs and cats with orbital abscess. In total, 34 dogs and 7 cats with orbital abscess participated in the study. Medical records of dogs and cats with a clinical diagnosis of orbital abscess, confirmed by cytologic or histopathologic evaluation of orbital specimens, were reviewed from the years 1990 to 2007. Animal signalment, presumptive source of microorganisms and mechanism of orbital introduction, bacterial isolates, and aerobic bacterial in vitro antimicrobial susceptibility test results were recorded. Percentages of susceptible aerobic bacterial isolates were compared among antimicrobials. Twenty dogs and five cats had positive culture results. The most frequent bacterial genera isolated from dogs were Staphylococcus, Escherichia, Bacteroides, Clostridium and Pasteurella. The most frequent bacterial genera isolated from cats were Pasteurella and Bacteroides. Aerobic bacterial isolates from dogs had the highest percentage of susceptibility to amikacin, ceftiofur, gentamicin, imipenem, ticarcillin and trimethoprim-sulfamethoxazole. Aerobic bacterial isolates from dogs had the lowest percentage of susceptibility to ampicillin, clindamycin, erythromycin and penicillin. Antimicrobial resistance was uncommon among feline aerobic bacterial isolates. The most commonly identified routes of orbital bacteria introduction were extension from adjacent anatomical structures, penetrating exogenous trauma, and foreign bodies. Mixed aerobic and anaerobic bacterial infections of the orbit occur commonly in dogs and cats. On the basis of aerobic and anaerobic bacterial isolates and in vitro susceptibility testing of aerobic bacterial isolates, cephalosporins, extended-spectrum penicillins, potentiated-penicillins and carbapenems are recommended for initial antimicrobial therapy of orbital abscess in dogs and cats.

  6. Xylan utilization in human gut commensal bacteria is orchestrated by unique modular organization of polysaccharide-degrading enzymes.

    Science.gov (United States)

    Zhang, Meiling; Chekan, Jonathan R; Dodd, Dylan; Hong, Pei-Ying; Radlinski, Lauren; Revindran, Vanessa; Nair, Satish K; Mackie, Roderick I; Cann, Isaac

    2014-09-02

    Enzymes that degrade dietary and host-derived glycans represent the most abundant functional activities encoded by genes unique to the human gut microbiome. However, the biochemical activities of a vast majority of the glycan-degrading enzymes are poorly understood. Here, we use transcriptome sequencing to understand the diversity of genes expressed by the human gut bacteria Bacteroides intestinalis and Bacteroides ovatus grown in monoculture with the abundant dietary polysaccharide xylan. The most highly induced carbohydrate active genes encode a unique glycoside hydrolase (GH) family 10 endoxylanase (BiXyn10A or BACINT_04215 and BACOVA_04390) that is highly conserved in the Bacteroidetes xylan utilization system. The BiXyn10A modular architecture consists of a GH10 catalytic module disrupted by a 250 amino acid sequence of unknown function. Biochemical analysis of BiXyn10A demonstrated that such insertion sequences encode a new family of carbohydrate-binding modules (CBMs) that binds to xylose-configured oligosaccharide/polysaccharide ligands, the substrate of the BiXyn10A enzymatic activity. The crystal structures of CBM1 from BiXyn10A (1.8 Å), a cocomplex of BiXyn10A CBM1 with xylohexaose (1.14 Å), and the CBM from its homolog in the Prevotella bryantii B14 Xyn10C (1.68 Å) reveal an unanticipated mode for ligand binding. A minimal enzyme mix, composed of the gene products of four of the most highly up-regulated genes during growth on wheat arabinoxylan, depolymerizes the polysaccharide into its component sugars. The combined biochemical and biophysical studies presented here provide a framework for understanding fiber metabolism by an important group within the commensal bacterial population known to influence human health.

  7. Bacterial indicators of pollution of the Douala lagoon, Cameroon: public health implications.

    Science.gov (United States)

    Akoachere, Jane-Francis T K; Oben, Pius M; Mbivnjo, Beryl S; Ndip, Lucy M; Nkwelang, Gerald; Ndip, Roland N

    2008-06-01

    Indiscriminate disposal of untreated wastes which are often heavily laden with sewage microorganisms some of which are pathogenic to humans into aquatic environments near cities could serve as potential dangers to human health. A prospective study was undertaken to investigate the scope of potential bacterial pathogens and to assess the extent of pollution of the Douala lagoon. A total of eighty water samples were collected fortnightly from the lagoon at five stations from March to October 2005 and analysed for heterotrophic bacterial densities, coliform counts, faecal coliform and faecal streptococcal counts. Bacteria were isolated and identified using standard microbiology and biochemical techniques. High heterotrophic bacterial counts (33 x 10(5) - 161 x 10(5) CFU/ mL), total coliform counts (1.8 x 10(2) - 2.4 x 10(2) CFU/100 mL), faecal coliform counts (2.2 x 10(2) - 2.4 x 10(2) CFU/ 100 mL) and faecal streptococcal counts (2.1 x 102 - 2.3 x 10(2) CFU/100mL were observed in all sampling stations. Eleven species of bacteria: Bacteroides fragilis, Proteus vulgaris, Klebsiella pneumoniae, E. coli, Enterococcus faecalis, Enterobacter aerogenes, Citrobacter freundii, Aeromonas hydrophila, Pseudomonas aeruginosa, Bacillus mycoides and Serratia marcesens, were frequently isolated. The presence of potential bacterial agents such as Bacteroides fragilis, Pseudomonas aeruginosa, Aeromonas hydrophila, Klebsiella pneumoniae and E. coli in the lagoon may pose a serious threat to the health and well being of users of the Lagoon and calls for urgent intervention.

  8. Bacteroidales Secreted Antimicrobial Proteins Target Surface Molecules Necessary for Gut Colonization and Mediate Competition In Vivo

    Directory of Open Access Journals (Sweden)

    Kevin G. Roelofs

    2016-08-01

    Full Text Available We recently showed that human gut Bacteroidales species secrete antimicrobial proteins (BSAPs, and we characterized in vitro the first such BSAP produced by Bacteroides fragilis. In this study, we identified a second potent BSAP produced by the ubiquitous and abundant human gut species Bacteroides uniformis. The two BSAPs contain a membrane attack complex/perforin (MACPF domain but share very little sequence similarity. We identified the target molecules of BSAP-sensitive cells and showed that each BSAP targets a different class of surface molecule: BSAP-1 targets an outer membrane protein of sensitive B. fragilis strains, and BSAP-2 targets the O-antigen glycan of lipopolysaccharide (LPS of sensitive B. uniformis strains. Species-wide genomic and phenotypic analyses of B. fragilis and B. uniformis showed that BSAP-producing strains circumvent killing by synthesizing an orthologous nontargeted surface molecule. The BSAP genes are adjacent to the gene(s encoding their target replacements, suggesting coacquisition. Using a gnotobiotic mouse competitive-colonization model, we found that the BSAP surface targets are important for colonization of the mammalian gut, thereby explaining why they are maintained in sensitive strains and why they were replaced rather than deleted in BSAP-producing strains. Using isogenic BSAP-producing, -sensitive, and -resistant strains, we show that a BSAP-producing strain outcompetes a sensitive strain but not a resistant strain in the mammalian gut. Human gut metagenomic datasets reveal that BSAP-1-sensitive strains do not cooccur with BSAP-1-producing strains in human gut microbiotas, further supporting the idea that BSAPs are important competitive factors with relevance to the strain-level composition of the human gut microbiota.

  9. Antimicrobial susceptibility of clinical isolates of anaerobic bacteria in Ontario, 2010-2011.

    Science.gov (United States)

    Marchand-Austin, Alex; Rawte, Prasad; Toye, Baldwin; Jamieson, Frances B; Farrell, David J; Patel, Samir N

    2014-08-01

    The local epidemiology of antimicrobial susceptibility patterns in anaerobic bacteria is important in guiding the empiric treatment of infections. However, susceptibility data are very limited on anaerobic organisms, particularly among non-Bacteroides organisms. To determine susceptibility profiles of clinically-significant anaerobic bacteria in Ontario Canada, anaerobic isolates from sterile sites submitted to Public Health Ontario Laboratory (PHOL) for identification and susceptibility testing were included in this study. Using the E-test method, isolates were tested for various antimicrobials including, penicillin, cefoxitin, clindamycin, meropenem, piperacillin-tazobactam and metronidazole. The MIC results were interpreted based on guidelines published by Clinical and Laboratory Standards Institute. Of 2527 anaerobic isolates submitted to PHOL, 1412 were either from sterile sites or bronchial lavage, and underwent susceptibility testing. Among Bacteroides fragilis, 98.2%, 24.7%, 1.6%, and 1.2% were resistant to penicillin, clindamycin, piperacillin-tazobactam, and metronidazole, respectively. Clostridium perfringens was universally susceptible to penicillin, piperacillin-tazobactam, and meropenem, whereas 14.2% of other Clostridium spp. were resistant to penicillin. Among Gram-positive anaerobes, Actinomyces spp., Parvimonas micra and Propionibacterium spp. were universally susceptible to β-lactams. Eggerthella spp., Collinsella spp., and Eubacterium spp. showed variable resistance to penicillin. Among Gram-negative anaerobes, Fusobacterium spp., Prevotella spp., and Veillonella spp. showed high resistance to penicillin but were universally susceptible to meropenem and piperacillin-tazobactam. The detection of metronidazole resistant B. fragilis is concerning as occurrence of these isolates is extremely rare. These data highlight the importance of ongoing surveillance to provide clinically relevant information to clinicians for empiric management of

  10. Performance of viruses and bacteriophages for fecal source determination in a multi-laboratory, comparative study.

    Science.gov (United States)

    Harwood, Valerie J; Boehm, Alexandria B; Sassoubre, Lauren M; Vijayavel, Kannappan; Stewart, Jill R; Fong, Theng-Theng; Caprais, Marie-Paule; Converse, Reagan R; Diston, David; Ebdon, James; Fuhrman, Jed A; Gourmelon, Michele; Gentry-Shields, Jennifer; Griffith, John F; Kashian, Donna R; Noble, Rachel T; Taylor, Huw; Wicki, Melanie

    2013-11-15

    An inter-laboratory study of the accuracy of microbial source tracking (MST) methods was conducted using challenge fecal and sewage samples that were spiked into artificial freshwater and provided as unknowns (blind test samples) to the laboratories. The results of the Source Identification Protocol Project (SIPP) are presented in a series of papers that cover 41 MST methods. This contribution details the results of the virus and bacteriophage methods targeting human fecal or sewage contamination. Human viruses used as source identifiers included adenoviruses (HAdV), enteroviruses (EV), norovirus Groups I and II (NoVI and NoVII), and polyomaviruses (HPyVs). Bacteriophages were also employed, including somatic coliphages and F-specific RNA bacteriophages (FRNAPH) as general indicators of fecal contamination. Bacteriophage methods targeting human fecal sources included genotyping of FRNAPH isolates and plaque formation on bacterial hosts Enterococcus faecium MB-55, Bacteroides HB-73 and Bacteroides GB-124. The use of small sample volumes (≤50 ml) resulted in relatively insensitive theoretical limits of detection (10-50 gene copies or plaques × 50 ml(-1)) which, coupled with low virus concentrations in samples, resulted in high false-negative rates, low sensitivity, and low negative predictive values. On the other hand, the specificity of the human virus methods was generally close to 100% and positive predictive values were ∼40-70% with the exception of NoVs, which were not detected. The bacteriophage methods were generally much less specific toward human sewage than virus methods, although FRNAPH II genotyping was relatively successful, with 18% sensitivity and 85% specificity. While the specificity of the human virus methods engenders great confidence in a positive result, better concentration methods and larger sample volumes must be utilized for greater accuracy of negative results, i.e. the prediction that a human contamination source is absent. Copyright

  11. Review article: dietary fibre-microbiota interactions.

    Science.gov (United States)

    Simpson, H L; Campbell, B J

    2015-07-01

    Application of modern rapid DNA sequencing technology has transformed our understanding of the gut microbiota. Diet, in particular plant-based fibre, appears critical in influencing the composition and metabolic activity of the microbiome, determining levels of short-chain fatty acids (SCFAs) important for intestinal health. To assess current epidemiological, experimental and clinical evidence of how long-term and short-term alterations in dietary fibre intake impact on the microbiome and metabolome. A Medline search including items 'intestinal microbiota', 'nutrition', 'diet', 'dietary fibre', 'SCFAs' and 'prebiotic effect' was performed. Studies found evidence of fibre-influenced differences in the microbiome and metabolome as a consequence of habitual diet, and of long-term or short-term intervention (in both animals and humans). Agrarian diets high in fruit/legume fibre are associated with greater microbial diversity and a predominance of Prevotella over Bacteroides. 'Western'-style diets, high in fat/sugar, low in fibre, decrease beneficial Firmicutes that metabolise dietary plant-derived polysaccharides to SCFAs and increase mucosa-associated Proteobacteria (including enteric pathogens). Short-term diets can also have major effects, particularly those exclusively animal-based, and those high-protein, low-fermentable carbohydrate/fibre 'weight-loss' diets, increasing the abundance of Bacteroides and lowering Firmicutes, with long-term adherence to such diets likely increasing risk of colonic disease. Interventions to prevent intestinal inflammation may be achieved with fermentable prebiotic fibres that enhance beneficial Bifidobacteria or with soluble fibres that block bacterial-epithelial adherence (contrabiotics). These mechanisms may explain many of the differences in microbiota associated with long-term ingestion of a diet rich in fruit and vegetable fibre. © 2015 The Authors. Alimentary Pharmacology & Therapeutics published by John Wiley & Sons Ltd.

  12. Xylan utilization in human gut commensal bacteria is orchestrated by unique modular organization of polysaccharide-degrading enzymes

    KAUST Repository

    Zhang, Meiling

    2014-08-18

    Enzymes that degrade dietary and host-derived glycans represent the most abundant functional activities encoded by genes unique to the human gut microbiome. However, the biochemical activities of a vast majority of the glycan-degrading enzymes are poorly understood. Here, we use transcriptome sequencing to understand the diversity of genes expressed by the human gut bacteria Bacteroides intestinalis and Bacteroides ovatus grown in monoculture with the abundant dietary polysaccharide xylan. The most highly induced carbohydrate active genes encode a unique glycoside hydrolase (GH) family 10 endoxylanase (BiXyn10A or BACINT-04215 and BACOVA-04390) that is highly conserved in the Bacteroidetes xylan utilization system. The BiXyn10A modular architecture consists of a GH10 catalytic module disrupted by a 250 amino acid sequence of unknown function. Biochemical analysis of BiXyn10A demonstrated that such insertion sequences encode a new family of carbohydrate-binding modules (CBMs) that binds to xy-lose- configured oligosaccharide/polysaccharide ligands, the substrate of the BiXyn10A enzymatic activity. The crystal structures of CBM1 from BiXyn10A (1.8 Å), a cocomplex of BiXyn10A CBM1 with xylohexaose (1.14 Å), and the CBM fromits homolog in the Prevotella bryantii B 14 Xyn10C (1.68 Å) reveal an unanticipated mode for ligand binding. Aminimal enzyme mix, composed of the gene products of four of the most highly up-regulated genes during growth on wheat arabinoxylan, depolymerizes the polysaccharide into its component sugars. The combined biochemical and biophysical studies presented here provide a framework for understanding fiber metabolism by an important group within the commensal bacterial population known to influence human health.

  13. Identifying keystone species in the human gut microbiome from metagenomic timeseries using sparse linear regression.

    Science.gov (United States)

    Fisher, Charles K; Mehta, Pankaj

    2014-01-01

    Human associated microbial communities exert tremendous influence over human health and disease. With modern metagenomic sequencing methods it is now possible to follow the relative abundance of microbes in a community over time. These microbial communities exhibit rich ecological dynamics and an important goal of microbial ecology is to infer the ecological interactions between species directly from sequence data. Any algorithm for inferring ecological interactions must overcome three major obstacles: 1) a correlation between the abundances of two species does not imply that those species are interacting, 2) the sum constraint on the relative abundances obtained from metagenomic studies makes it difficult to infer the parameters in timeseries models, and 3) errors due to experimental uncertainty, or mis-assignment of sequencing reads into operational taxonomic units, bias inferences of species interactions due to a statistical problem called "errors-in-variables". Here we introduce an approach, Learning Interactions from MIcrobial Time Series (LIMITS), that overcomes these obstacles. LIMITS uses sparse linear regression with boostrap aggregation to infer a discrete-time Lotka-Volterra model for microbial dynamics. We tested LIMITS on synthetic data and showed that it could reliably infer the topology of the inter-species ecological interactions. We then used LIMITS to characterize the species interactions in the gut microbiomes of two individuals and found that the interaction networks varied significantly between individuals. Furthermore, we found that the interaction networks of the two individuals are dominated by distinct "keystone species", Bacteroides fragilis and Bacteroided stercosis, that have a disproportionate influence on the structure of the gut microbiome even though they are only found in moderate abundance. Based on our results, we hypothesize that the abundances of certain keystone species may be responsible for individuality in the human gut

  14. Effect of Functional Oligosaccharides and Ordinary Dietary Fiber on Intestinal Microbiota Diversity.

    Science.gov (United States)

    Cheng, Weiwei; Lu, Jing; Li, Boxing; Lin, Weishi; Zhang, Zheng; Wei, Xiao; Sun, Chengming; Chi, Mingguo; Bi, Wei; Yang, Bingjun; Jiang, Aimin; Yuan, Jing

    2017-01-01

    Functional oligosaccharides, known as prebiotics, and ordinary dietary fiber have important roles in modulating the structure of intestinal microbiota. To investigate their effects on the intestinal microecosystem, three kinds of diets containing different prebiotics were used to feed mice for 3 weeks, as follows: GI (galacto-oligosaccharides and inulin), PF (polydextrose and insoluble dietary fiber from bran), and a GI/PF mixture (GI and PF, 1:1), 16S rRNA gene sequencing and metabolic analysis of mice feces were then conducted. Compared to the control group, the different prebiotics diets had varying effects on the structure and diversity of intestinal microbiota. GI and PF supplementation led to significant changes in intestinal microbiota, including an increase of Bacteroides and a decrease of Alloprevotella in the GI-fed, but those changes were opposite in PF fed group. Intriguing, in the GI/PF mixture-fed group, intestinal microbiota had the similar structure as the control groups, and flora diversity was upregulated. Fecal metabolic profiling showed that the diversity of intestinal microbiota was helpful in maintaining the stability of fecal metabolites. Our results showed that a single type of oligosaccharides or dietary fiber caused the reduction of bacteria species, and selectively promoted the growth of Bacteroides or Alloprevotella bacteria, resulting in an increase in diamine oxidase (DAO) and/or trimethylamine N-oxide (TMAO) values which was detrimental to health. However, the flora diversity was improved and the DAO values was significantly decreased when the addition of nutritionally balanced GI/PF mixture. Thus, we suggested that maintaining microbiota diversity and the abundance of dominant bacteria in the intestine is extremely important for the health, and that the addition of a combination of oligosaccharides and dietary fiber helps maintain the health of the intestinal microecosystem.

  15. [Analysis of diversity of vaginal microbiota in healthy Chinese women by using DNA-fingerprinting].

    Science.gov (United States)

    Xiao, Bing-bing; Liao, Qin-ping

    2012-04-18

    To analyze the diversity of healthy women's vaginal dominant flora in different physiological states with PCR-denaturing gradient gel electrophoresis (PCR-DGGE), to establish the basis for the future study of lower genital tract infections, and to provide a theoretical basis for the development of vaginal probiotics adapted to Chinese females. Women who underwent routine gynecologic examinations in Peking University First Hospital from October 2009 to January 2010 were enrolled, including 30 at reproductive age and 30 at post menopause age. Vaginal samples were collected and then total bacterial DNA was extracted. Universal bacterial primers were used to amplify the V3 region of 16S rDNA gene. PCR products were analyzed by denatured gradient gel electrophoresis (DGGE). Featured bands on DGGE were recovered, cloned and sequenced. Alignment with known sequence was made by using Blast on GenBank to identify bacterial strains so as to analyze the diversity of healthy women's vaginal dominant flora in different physiological states. (1) Vaginal flora in healthy Chinese women at their reproductive age were relatively simple, Lactobacillus were the dominant bacteria. Common bacteria included: Lactobacillus crispatus, Lactobacillus iners,and Lactobacillus gasseri. While L. iners were the dominant vaginal bacteria that could not be recognized by traditional method. (2) Vaginal bacteria in the women at post menopause age were more complex than in those at reproductive age. Common bacteria included: Lactobacillus iners, Lactobacillus crispatus, Escherichia coli, Streptococcus agalactiae, Streptococcus gallolyticus, Veillonella sp., Streptococcus intermedius, Streptococcus anginosus, Prevotella sp., Anaerococcus lactolyticus and Bacteroides fragilis. Based on the DGGE analysis, the most common vaginal bacteria in Chinese healthy women at reproductive age are Lactobacillus crispatus, Lactobacillus iners,and Lactobacillus gasseri. the most common vaginal bacteria in healthy post

  16. In vitro effects of inulin and soya bean oligosaccharide on skatole production and the intestinal microbiota in broilers.

    Science.gov (United States)

    Liu, H Y; Hou, R; Yang, G Q; Zhao, F; Dong, W G

    2017-11-03

    The experiment was conducted to investigate the in vitro effects of inulin and soya bean oligosaccharide (SBO) on the metabolism of L-tryptophan (L-try) to skatole production, and the intestinal microbiota in broilers. Treatments were as follows: caecal microbiota control (Cc), Cc + inulin, Cc + SBO, rectal microbiota control (Rc), Rc + inulin and Rc + SBO. Microbial suspensions were anaerobically incubated at 38°C for 24 hr. The results showed that concentrations of skatole and acetic acid were significantly lower in caecal microbiota fermentation broth (MFB) than those in rectal MFB (p inulin or SBO significantly decreased the concentrations of indole and skatole and rate of L-try degradation (p Inulin groups had lower indole than SBO groups (p inulin or SBO decreased the microbiota richness (p  .05). Four distinct bands were detected in inulin and SBO groups, which were related to two of Bacteroides, one of Firmicutes and Bifidobacteria. Six bands were detected only in control groups, which represented uncultured Rikenellaceae, Roseburia, Escherichia/Shigella dysenteriae, Bacteroides uniformis (T), Parabacteroides distasonis and Enterobacter aerogenes. Populations of Lactobacilli, Bifidobacteria and total bacteria in inulin groups were higher than those in control groups (p  .05). These results suggest that reduced concentrations of skatole and indole in the presence of inulin and SBO may be caused by decrease in L-try degradation rate, which were caused by change in microbial ecosystem and pH value. Uncultured B. uniformis (T) and E. aerogenes may be responsible for degradation of L-try to skatole. © 2017 Blackwell Verlag GmbH.

  17. In silico insights into the symbiotic nitrogen fixation in Sinorhizobium meliloti via metabolic reconstruction.

    Science.gov (United States)

    Zhao, Hansheng; Li, Mao; Fang, Kechi; Chen, Wenfeng; Wang, Jing

    2012-01-01

    Sinorhizobium meliloti is a soil bacterium, known for its capability to establish symbiotic nitrogen fixation (SNF) with leguminous plants such as alfalfa. S. meliloti 1021 is the most extensively studied strain to understand the mechanism of SNF and further to study the legume-microbe interaction. In order to provide insight into the metabolic characteristics underlying the SNF mechanism of S. meliloti 1021, there is an increasing demand to reconstruct a metabolic network for the stage of SNF in S. meliloti 1021. Through an iterative reconstruction process, a metabolic network during the stage of SNF in S. meliloti 1021 was presented, named as iHZ565, which accounts for 565 genes, 503 internal reactions, and 522 metabolites. Subjected to a novelly defined objective function, the in silico predicted flux distribution was highly consistent with the in vivo evidences reported previously, which proves the robustness of the model. Based on the model, refinement of genome annotation of S. meliloti 1021 was performed and 15 genes were re-annotated properly. There were 19.8% (112) of the 565 metabolic genes included in iHZ565 predicted to be essential for efficient SNF in bacteroids under the in silico microaerobic and nutrient sharing condition. As the first metabolic network during the stage of SNF in S. meliloti 1021, the manually curated model iHZ565 provides an overview of the major metabolic properties of the SNF bioprocess in S. meliloti 1021. The predicted SNF-required essential genes will facilitate understanding of the key functions in SNF and help identify key genes and design experiments for further validation. The model iHZ565 can be used as a knowledge-based framework for better understanding the symbiotic relationship between rhizobia and legumes, ultimately, uncovering the mechanism of nitrogen fixation in bacteroids and providing new strategies to efficiently improve biological nitrogen fixation.

  18. Microbial community mapping in intestinal tract of broiler chicken.

    Science.gov (United States)

    Xiao, Yingping; Xiang, Yun; Zhou, Weidong; Chen, Jinggang; Li, Kaifeng; Yang, Hua

    2017-05-01

    Domestic chickens are valuable sources of protein associated with producing meat and eggs for humans. The gastrointestinal tract (GIT) houses a large microbial community, and these microbiota play an important role in growth and health of chickens, contributing to the enhancement of nutrient absorption and improvement of the birds' immune systems. To improve our understanding of the chicken intestinal microbial composition, microbiota inhabiting 5 different intestinal locations (duodenum, jejunum, ileum, cecum, and colon) of 42-day-old broiler chickens were detected based on 16S rRNA gene sequence analysis. As a result, 1,502,554 sequences were clustered into 796 operational taxonomic units (OTUs) at the 97% sequence similarity value and identified into 15 phyla and 288 genera. Firmicutes, Bacteroidetes, Proteobacteria, Actinobacteria, and Cyanobacteria were the major microbial groups and Firmicutes was the dominant phylum in duodenum, jejunum, ileum and colon accounting for > 60% of sequences, while Bacteroidetes was the dominant phylum in cecum (>50% of sequences), but little in the other four gut sections. At the genus level, the major microbial genera across all gut sections were Lactobacillus, Enterococcus, Bacteroides, and Corynebacterium. Lactobacillus was the predominant genus in duodenum, jejunum, and ileum (>35%), but was rarely present in cecum, and Bacteroides was the most dominant group in cecum (about 40%), but rarely present in the other 4 intestinal sections. Differences of microbial composition between the 5 intestinal locations might be a cause and consequence of gut functional differences and may also reflect host selection mediated by innate or adaptive immune responses. All these results could offer some information for the future study on the relationship between intestinal microbiota and broiler chicken growth performance as well as health. © 2016 Poultry Science Association Inc.

  19. Phylogenetic diversity of dissimilatory ferric iron reducers in paddy soil of Hunan, South China

    Energy Technology Data Exchange (ETDEWEB)

    Wang Xin-Jun [State Key Lab. of Urban and Regional Ecology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, BJ (China); Graduate Univ., Chinese Academy of Sciences, BJ (China); Yang Jing; Chen Xue-Ping; Sun Guo-Xin [State Key Lab. of Urban and Regional Ecology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, BJ (China); Zhu Yong-Guan [State Key Lab. of Urban and Regional Ecology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, BJ (China); Key Lab. of Urban Environment and Health, Inst. of Urban Environment, Chinese Academy of Sciences, Xiamen (China)

    2009-12-15

    Purpose: Dissimilatory iron-reducing bacteria have been described by both culture-dependent and -independent methods in various environments, including freshwater, marine sediments, natural wetlands, and contaminated aquifers. However, little is known about iron-reducing microbial communities in paddy soils. The goal of this study was to characterize iron-reducing microbial communities in paddy soil. Moreover, the effect of dissolved and solid-phase iron (III) species on the iron-reducing microbial communities was also investigated by enrichment cultures. Methods: Ferric citrate and ferrihydrite were used respectively to set up enrichment cultures of dissimilatory ironreducing microorganisms using 1% inoculum of soil samples, and the iron reduction was measured. Moreover, bacterial DNA was extracted and 16S rRNA genes were PCR-amplified, and subsequently analyzed by the clone library and terminal restriction fragment length polymorphism (T-RFLP). Results: Phylogenetic analysis of 16S rRNA gene sequences extracted from the enrichment cultures revealed that Bradyrhizobium, Bacteroides, Clostridium and Ralstonia species were the dominant bacteria in the ferric citrate enrichment. However, members of the genera Clostridium, Bacteroides, and Geobacter were the dominant micro-organisms in the ferrihydrite enrichment. Analysis of enrichment cultures by T-RFLP strongly supported the cloning and sequencing results. Conclusions: The present study demonstrated that dissimilatory iron-reducing consortia in As-contaminated paddy soil are phylogenetically diverse. Moreover, iron (III) sources as a key factor have a strong effect on the iron (III)-reducing microbial community structure and relative abundance in the enrichments. In addition, Geobacter species are selectively enriched by ferrihydrite enrichment cultures. (orig.)

  20. Effects of the Brown Seaweed Laminaria japonica Supplementation on Serum Concentrations of IgG, Triglycerides, and Cholesterol, and Intestinal Microbiota Composition in Rats

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    Jae-Young Kim

    2018-04-01

    Full Text Available The intestinal microbial communities play critical roles in various aspects of body function of the host. Prebiotics, such as dietary fiber, can affect health of the host by altering the composition of intestinal microbiota. Although brown seaweed Laminaria japonica is rich in dietary fiber, studies on its prebiotic potential are quite rare. In this study, basal diet (control, basal diet supplemented with dried L. japonica (DLJ, heat-treated dried L. japonica (HLJ, or heated dried L. japonica with added fructooligosaccharide (FHLJ was fed to rats for 16 weeks. Serum concentrations of IgG, triglyceride, and cholesterol were measured. In addition, the intestinal microbiota composition was analyzed by high-throughput sequencing of 16S rRNA gene. As compared to the control group, DLJ, HLJ, and FHLJ groups showed significantly higher serum IgG concentration, but had lower weight gain and serum triglyceride concentration. Moreover, DLJ, HLJ, and FHLJ groups showed lower Fimicutes to Bacteroidetes ratio when compared with the control group. As compared with the control group, obesity-associated bacterial genera (Allobaculum, Turicibacter, Coprobacillus, Mollicute, and Oscilibacter, and the genera with pathogenic potentials (Mollicute, Bacteroides, Clostridium, Escherichia, and Prevotella decreased while leanness-associated genera (Alistipes, Bacteroides, and Prevotella, and lactic acid bacterial genera (Subdoligranulum, Streptococcus, Lactobacillus, Enterococcus, and Bifidobacterium increased in all treatment groups. On the contrary, butyric acid producing genera including Subdoligranulum, Roseburia, Eubacterium, Butyrivibrio, and Anaerotruncus increased significantly only in FHLJ group. The overall results support multiple prebiotic effects of seaweed L. japonica on rats as determined by body weight reduction, enhanced immune response, and desirable changes in intestinal microbiota composition, suggesting the great potential of L. japonica as an

  1. Extracellular vesicles in gastrointestinal cancer in conjunction with microbiota: On the border of Kingdoms

    KAUST Repository

    Barteneva, Natasha S.

    2017-06-29

    Extracellular vesicle (EV) production is a universal feature of metazoan cells as well as prokaryotes (bMVs - bacterial microvesicls). They are small vesicles with phospholipid membrane carrying proteins, DNA and different classes of RNAs and are heavily involved in intercellular communication acting as vectors of information to target cells. For the last decade, the interest in EV research has exponentially increased though thorough studies of their roles in various pathologies that was not previously possible due to technical limitations.This review focuses on research evaluating the role of EV production in gastrointestinal (GI) cancer development in conjunction with GI microbiota and inflammatory diseases. We also discuss recent studies on the promising role of EVs and their content as biomarkers for early diagnosis of GI cancers. The bMVs have also been implicated in the pathogenesis of GI chronic inflammatory diseases, however, possible role of bMVs in tumorigenesis remains underestimated. We propose that EVs from eukaryotic cells as well as from different microbial, fungi, parasitic species and edible plants in GI tract act as mediators of intracellular and inter-species communication, particularly facilitating tumour cell survival and multi-drug resistance. In conclusion, we suggest that matching sequences from EV proteomes (available from public databases) with known protein sequences of microbiome gut bacteria will be useful in identification of antigen mimicry between evolutionary conservative protein sequences. Using this approach we identified Bacteroides spp. pseudokinase with activation loop and homology to PDGFRα, providing a proof-of-concept strategy. We speculate that existence of microbial pseudokinase that ‘mimic” PDGFRα may be related to PDGFRα and Bacteroides spp. roles in colorectal carcinogenesis that require further investigation.

  2. Balancing Herbal Medicine and Functional Food for Prevention and Treatment of Cardiometabolic Diseases through Modulating Gut Microbiota

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    Ming Lyu

    2017-11-01

    Full Text Available It has become apparent that gut microbiota is closely associated with cardiometabolic diseases (CMDs, and alteration in microbiome compositions is also linked to the host environment. Next generation sequencing (NGS has facilitated in-depth studies on the effects of herbal medicine and functional food on gut microbiota. Both herbal medicine and functional food contain fiber, polyphenols and polysaccharides, exerting prebiotics-like activities in the prevention and treatment of CMDs. The administrations of herbal medicine and functional food lead to increased the abundance of phylum Bacteroidetes, and genus Akkermansia, Bifidobacteria, Lactobacillus, Bacteroides and Prevotella, while reducing phylum Firmicutes and Firmicutes/Bacteroidetes ratio in gut. Both herbal medicine and functional food interact with gut microbiome and alter the microbial metabolites including short-chain fatty acids (SCFAs, bile acids (BAs and lipopolysaccharides (LPS, which are now correlated with metabolic diseases such as type 2 diabetes (T2D, obesity and non-alcoholic fatty liver disease (NAFLD. In addition, trimethylamine (TMA-N-oxide (TMAO is recently linked to atherosclerosis (AS and cardiovascular disease (CVD risks. Moreover, gut-organs axes may serve as the potential strategy for treating CMDs with the intervention of herbal medicine and functional food. In summary, a balance between herbal medicine and functional food rich in fiber, polyphenols and polysaccharides plays a vital role in modulating gut microbiota (phylum Bacteroidetes, Firmicutes and Firmicutes/Bacteroidetes ratio, and genus Akkermansia, Bifidobacteria, Lactobacillus, Bacteroides and Prevotella through SCFAs, BAs, LPS and TMAO signaling regarding CMDs. Targeting gut-organs axes may serve as a new therapeutic strategy for CMDs by herbal medicine and functional food in the future. This review aims to summarize the balance between herbal medicine and functional food utilized for the prevention and

  3. Balancing Herbal Medicine and Functional Food for Prevention and Treatment of Cardiometabolic Diseases through Modulating Gut Microbiota.

    Science.gov (United States)

    Lyu, Ming; Wang, Yue-Fei; Fan, Guan-Wei; Wang, Xiao-Ying; Xu, Shuang-Yong; Zhu, Yan

    2017-01-01

    It has become apparent that gut microbiota is closely associated with cardiometabolic diseases (CMDs), and alteration in microbiome compositions is also linked to the host environment. Next generation sequencing (NGS) has facilitated in-depth studies on the effects of herbal medicine and functional food on gut microbiota. Both herbal medicine and functional food contain fiber, polyphenols and polysaccharides, exerting prebiotics-like activities in the prevention and treatment of CMDs. The administrations of herbal medicine and functional food lead to increased the abundance of phylum Bacteroidetes, and genus Akkermansia, Bifidobacteria, Lactobacillus, Bacteroides and Prevotella , while reducing phylum Firmicutes and Firmicutes/Bacteroidetes ratio in gut. Both herbal medicine and functional food interact with gut microbiome and alter the microbial metabolites including short-chain fatty acids (SCFAs), bile acids (BAs) and lipopolysaccharides (LPS), which are now correlated with metabolic diseases such as type 2 diabetes (T2D), obesity and non-alcoholic fatty liver disease (NAFLD). In addition, trimethylamine (TMA)-N-oxide (TMAO) is recently linked to atherosclerosis (AS) and cardiovascular disease (CVD) risks. Moreover, gut-organs axes may serve as the potential strategy for treating CMDs with the intervention of herbal medicine and functional food. In summary, a balance between herbal medicine and functional food rich in fiber, polyphenols and polysaccharides plays a vital role in modulating gut microbiota (phylum Bacteroidetes, Firmicutes and Firmicutes/Bacteroidetes ratio, and genus Akkermansia, Bifidobacteria, Lactobacillus, Bacteroides and Prevotella ) through SCFAs, BAs, LPS and TMAO signaling regarding CMDs. Targeting gut-organs axes may serve as a new therapeutic strategy for CMDs by herbal medicine and functional food in the future. This review aims to summarize the balance between herbal medicine and functional food utilized for the prevention and

  4. Mortality in necrotizing fasciitis

    International Nuclear Information System (INIS)

    Waseem, A.R.; Samad, A.

    2008-01-01

    The objective of this study was to determine the mortality rate in patients presenting with Necrotizing Fasciitis. This prospective study was conducted at ward 26, JPMC Karachi over a period of two years from March 2001 to Feb 2003. All patients above the age of 12 years diagnosed to be having Necrotizing Fasciitis and admitted through the Accident and emergency department were included in this study. After resuscitation, the patients underwent the emergency exploration and aggressive surgical debridement. Post-operatively, the patients were managed in isolated section of the ward. The patients requiring grafting were referred to plastic surgery unit. The patients were followed up in outpatients department for about two years. Over all, 25 male and 5 female patients fulfilled the inclusion criteria and were included in this study. The common clinical manifestations include redness, swelling, discharging abscess, pain, fever, skin necrosis and foul smelling discharge etc. The most common predisposing factor was Diabetes mellitus whereas the most commonly involved site was perineum. All patients underwent aggressive and extensive surgical debridements. The common additional procedures included Skin grafting, Secondary suturing, Cystostomy and Orchidectomy. Bacteroides and E. coli were the main micro-organisms isolated in this study. Bacteroides was the most common microorganism isolated among the eight patients who died. Necrotizing Fasciitis is a potentially life threatening emergency condition and carries the mortality rate of about 26.6%. The major contributing factors to increase the mortality missed initially diagnosed, old age, diabetes mellitus truncal involvement and late presentation. Anorectal involvement of disease carry worse prognosis. Hyperbaric oxygen therapy and proper use of unprocessed honey reduced the mortality rate. (author)

  5. Disrupted intestinal microbiota and intestinal inflammation in children with cystic fibrosis and its restoration with Lactobacillus GG: a randomised clinical trial.

    Directory of Open Access Journals (Sweden)

    Eugenia Bruzzese

    Full Text Available Intestinal inflammation is a hallmark of cystic fibrosis (CF. Administration of probiotics can reduce intestinal inflammation and the incidence of pulmonary exacerbations. We investigated the composition of intestinal microbiota in children with CF and analyzed its relationship with intestinal inflammation. We also investigated the microflora structure before and after Lactobacillus GG (LGG administration in children with CF with and without antibiotic treatment.The intestinal microbiota were analyzed by denaturing gradient gel electrophoresis (DGGE, real-time polymerase chain reaction (RT-PCR, and fluorescence in situ hybridization (FISH. Intestinal inflammation was assessed by measuring fecal calprotectin (CLP and rectal nitric oxide (rNO production in children with CF as compared with healthy controls. We then carried out a small double-blind randomized clinical trial with LGG.Twenty-two children with CF children were enrolled in the study (median age, 7 years; range, 2-9 years. Fecal CLP and rNO levels were higher in children with CF than in healthy controls (184±146 µg/g vs. 52±46 µg/g; 18±15 vs. 2.6±1.2 µmol/L NO2 (-, respectively; P<0.01. Compared with healthy controls, children with CF had significantly different intestinal microbial core structures. The levels of Eubacterium rectale, Bacteroides uniformis, Bacteroides vulgatus, Bifidobacterium adolescentis, Bifidobacterium catenulatum, and Faecalibacterium prausnitzii were reduced in children with CF. A similar but more extreme pattern was observed in children with CF who were taking antibiotics. LGG administration reduced fecal CLP and partially restored intestinal microbiota. There was a significant correlation between reduced microbial richness and intestinal inflammation.CF causes qualitative and quantitative changes in intestinal microbiota, which may represent a novel therapeutic target in the treatment of CF. Administration of probiotics restored gut microbiota, supporting

  6. Characterization of Microbiota in Children with Chronic Functional Constipation.

    Science.gov (United States)

    de Meij, Tim G J; de Groot, Evelien F J; Eck, Anat; Budding, Andries E; Kneepkens, C M Frank; Benninga, Marc A; van Bodegraven, Adriaan A; Savelkoul, Paul H M

    2016-01-01

    Disruption of the intestinal microbiota is considered an etiological factor in pediatric functional constipation. Scientifically based selection of potential beneficial probiotic strains in functional constipation therapy is not feasible due to insufficient knowledge of microbiota composition in affected subjects. The aim of this study was to describe microbial composition and diversity in children with functional constipation, compared to healthy controls. Fecal samples from 76 children diagnosed with functional constipation according to the Rome III criteria (median age 8.0 years; range 4.2-17.8) were analyzed by IS-pro, a PCR-based microbiota profiling method. Outcome was compared with intestinal microbiota profiles of 61 healthy children (median 8.6 years; range 4.1-17.9). Microbiota dissimilarity was depicted by principal coordinate analysis (PCoA), diversity was calculated by Shannon diversity index. To determine the most discriminative species, cross validated logistic ridge regression was performed. Applying total microbiota profiles (all phyla together) or per phylum analysis, no disease-specific separation was observed by PCoA and by calculation of diversity indices. By ridge regression, however, functional constipation and controls could be discriminated with 82% accuracy. Most discriminative species were Bacteroides fragilis, Bacteroides ovatus, Bifidobacterium longum, Parabacteroides species (increased in functional constipation) and Alistipes finegoldii (decreased in functional constipation). None of the commonly used unsupervised statistical methods allowed for microbiota-based discrimination of children with functional constipation and controls. By ridge regression, however, both groups could be discriminated with 82% accuracy. Optimization of microbiota-based interventions in constipated children warrants further characterization of microbial signatures linked to clinical subgroups of functional constipation.

  7. Molecular analysis of the gut microbiota of identical twins with Crohn's disease

    Energy Technology Data Exchange (ETDEWEB)

    Jansson, Janet; Dicksved, Johan; Halfvarson, Jonas; Rosenquist, Magnus; Jarnerot, Gunnar; Tysk, Curt; Apajalahti, Juha; Engstrand, Lars; Jansson, Janet K.

    2008-03-14

    Increasing evidence suggests that a combination of host genetics and the composition of the gut microbiota are important for development of Crohn's disease (CD). Our aim was to study identical twins with CD to determine microbial factors independently of host genetics. Fecal samples were studied from 10 monozygotic twin pairs with CD (discordant n=6, concordant n=4) and 8 healthy twin pairs. DNA was extracted, 16S rRNA genes were PCR amplified and T-RFLP fingerprints generated using general bacterial and Bacteroides group specific primers. The microbial communities were also profiled based on their % G+C contents. Bacteroides 16S rRNA genes were cloned and sequenced from a subset of the samples. The bacterial diversity in each sample and similarity indices between samples were estimated based on the T-RFLP data using a combination of statistical approaches. Healthy individuals had a significantly higher bacterial diversity compared to individuals with CD. The fecal microbial communities were more similar between healthy twins than between twins with CD, especially when these were discordant for the disease. The microbial community profiles of individuals with ileal CD were significantly different from healthy individuals and those with colonic CD. Also, CD individuals had a lower relative abundance of B. uniformis and higher relative abundances of B. ovatus and B. vulgatus. Our results suggest that genetics and/or environmental exposure during childhood in part determine the gut microbial composition. However, CD is associated with dramatic changes in the gut microbiota and this was particularly evident for individuals with ileal CD.

  8. Feeding broilers with dry whey powder and whey protein concentrate affected productive performance, ileal digestibility of nutrients and cecal microbiota community.

    Science.gov (United States)

    Pineda-Quiroga, C; Camarinha-Silva, A; Borda-Molina, D; Atxaerandio, R; Ruiz, R; García-Rodríguez, A

    2018-04-01

    Dietary interventions are a common practice in the poultry industry to promote optimal performance and health of animals. Here, we aim at assessing the influence of supplementing broiler diets with dry whey powder (DWP) and whey protein concentrate (WPC) on nutrient coefficient of apparent ileal digestibility (CAID) and productive performance. Cecal microbiota composition was also determined using Illumina amplicon sequencing. Dietary treatments were control diet (no supplementation of DWP or WPC), 60-DWP (60 g/kg of DWP), and 80-WPC (80 g/kg of WPC). One-day-old male broilers were randomly assigned to one of three treatments, and housed in floor pens. In Trial 1, 90 1-day-old chicks were allocated to three pens/treatment, with 10 birds/pen, during 21 days for CAID evaluation. Diet 60-DWP increased Ca CAID (P=0.041), while diet 80-WPC improved Ca and P CAID (PWPC increased their BW, average daily gain (ADG) and feed intake (FI) during the starter (PWPC reduced the feed conversion ratio of chickens during the starter period (PWPC differed from those fed with control diet (R=0.776, P=0.008; and R=0.740, P=0.008, respectively). The abundance of Bacteroides fragilis, Bacteroides spp., Escherichia coli/Shigella flexneri and Megamonas furniformis increased when 60-DWP and 80-WPC diets were offered, while the presence of Helicobacter pullorum decreased. Lactobacillus salivarius consistently increased in chickens with better feed conversion ratio, which were those fed with 60-DWP. The results obtained in the present study indicate that growth of chickens is improved by DWP and WPC supplementation because of a higher mineral digestibility, increased feed intake and modulation of cecal microbiota communities.

  9. Identifying keystone species in the human gut microbiome from metagenomic timeseries using sparse linear regression.

    Directory of Open Access Journals (Sweden)

    Charles K Fisher

    Full Text Available Human associated microbial communities exert tremendous influence over human health and disease. With modern metagenomic sequencing methods it is now possible to follow the relative abundance of microbes in a community over time. These microbial communities exhibit rich ecological dynamics and an important goal of microbial ecology is to infer the ecological interactions between species directly from sequence data. Any algorithm for inferring ecological interactions must overcome three major obstacles: 1 a correlation between the abundances of two species does not imply that those species are interacting, 2 the sum constraint on the relative abundances obtained from metagenomic studies makes it difficult to infer the parameters in timeseries models, and 3 errors due to experimental uncertainty, or mis-assignment of sequencing reads into operational taxonomic units, bias inferences of species interactions due to a statistical problem called "errors-in-variables". Here we introduce an approach, Learning Interactions from MIcrobial Time Series (LIMITS, that overcomes these obstacles. LIMITS uses sparse linear regression with boostrap aggregation to infer a discrete-time Lotka-Volterra model for microbial dynamics. We tested LIMITS on synthetic data and showed that it could reliably infer the topology of the inter-species ecological interactions. We then used LIMITS to characterize the species interactions in the gut microbiomes of two individuals and found that the interaction networks varied significantly between individuals. Furthermore, we found that the interaction networks of the two individuals are dominated by distinct "keystone species", Bacteroides fragilis and Bacteroided stercosis, that have a disproportionate influence on the structure of the gut microbiome even though they are only found in moderate abundance. Based on our results, we hypothesize that the abundances of certain keystone species may be responsible for individuality in

  10. Disrupted intestinal microbiota and intestinal inflammation in children with cystic fibrosis and its restoration with Lactobacillus GG: a randomised clinical trial.

    Science.gov (United States)

    Bruzzese, Eugenia; Callegari, Maria Luisa; Raia, Valeria; Viscovo, Sara; Scotto, Riccardo; Ferrari, Susanna; Morelli, Lorenzo; Buccigrossi, Vittoria; Lo Vecchio, Andrea; Ruberto, Eliana; Guarino, Alfredo

    2014-01-01

    Intestinal inflammation is a hallmark of cystic fibrosis (CF). Administration of probiotics can reduce intestinal inflammation and the incidence of pulmonary exacerbations. We investigated the composition of intestinal microbiota in children with CF and analyzed its relationship with intestinal inflammation. We also investigated the microflora structure before and after Lactobacillus GG (LGG) administration in children with CF with and without antibiotic treatment. The intestinal microbiota were analyzed by denaturing gradient gel electrophoresis (DGGE), real-time polymerase chain reaction (RT-PCR), and fluorescence in situ hybridization (FISH). Intestinal inflammation was assessed by measuring fecal calprotectin (CLP) and rectal nitric oxide (rNO) production in children with CF as compared with healthy controls. We then carried out a small double-blind randomized clinical trial with LGG. Twenty-two children with CF children were enrolled in the study (median age, 7 years; range, 2-9 years). Fecal CLP and rNO levels were higher in children with CF than in healthy controls (184±146 µg/g vs. 52±46 µg/g; 18±15 vs. 2.6±1.2 µmol/L NO2 (-), respectively; P<0.01). Compared with healthy controls, children with CF had significantly different intestinal microbial core structures. The levels of Eubacterium rectale, Bacteroides uniformis, Bacteroides vulgatus, Bifidobacterium adolescentis, Bifidobacterium catenulatum, and Faecalibacterium prausnitzii were reduced in children with CF. A similar but more extreme pattern was observed in children with CF who were taking antibiotics. LGG administration reduced fecal CLP and partially restored intestinal microbiota. There was a significant correlation between reduced microbial richness and intestinal inflammation. CF causes qualitative and quantitative changes in intestinal microbiota, which may represent a novel therapeutic target in the treatment of CF. Administration of probiotics restored gut microbiota, supporting the

  11. Alterations in the gut microbiota of patients with acquired immune deficiency syndrome.

    Science.gov (United States)

    Zhou, Youlian; Ou, Zhitao; Tang, Xiaoping; Zhou, Yongjian; Xu, Haoming; Wang, Xianfei; Li, Kang; He, Jie; Du, Yanlei; Wang, Hong; Chen, Ye; Nie, Yuqiang

    2018-02-07

    Acquired immune deficiency syndrome (AIDS), caused by infection with human immunodeficiency virus (HIV), is associated with gastrointestinal disease, systemic immune activation and changes in the gut microbiota. Here, we aim to investigate the gut microbiota patterns of HIV-infected individuals and HIV-uninfected individuals in populations from South China. We enrolled 33 patients with HIV (14 participants treated with highly active antiretroviral therapy [HAART] for more than 3 months; the remaining 19 individuals had not received treatment) and 35 healthy controls (HC) for a cross-sectional comparison of gut microbiota using stool samples. Gut microbial communities were profiled by sequencing the bacterial 16S rRNA genes. Dysbiosis was more common among patients with AIDS compared with healthy individuals. Dysbiosis was characterized by decreased α-diversity, low mean counts of Bacteroidetes, Faecalibacterium, Prevotella, Bacteroides vulgatus, Dialister and Roseburia inulnivorans, and high mean counts of Proteobacteria, Enterococcus, Streptococcus, Lactobacillus, Lachnociostridium, Ruminococcus gnavus and Streptococcus vestibularis. Increased abundance of Bacilli was observed in homosexual patients. Proteobacteria were higher among heterosexual patients with HIV infections. Tenericutes were higher among patients with history of intravenous drug abuse. Restoration of gut microbiota diversity and a significant increase in abundance of Faecalibacterium, Blautia and Bacteroides were found in patients receiving HAART compared to those who did not receive. HIV infection-associated dysbiosis is characterized by decreased levels of α-diversity and Bacteroidetes, increased levels of Proteobacteria and the alterations of gut microbiota correlate with the route of HIV transmission. The imbalanced faecal microbiota of HIV infection is partially restored after therapy. © 2018 The Authors. Journal of Cellular and Molecular Medicine published by John Wiley & Sons Ltd and

  12. Rhizobia symbiosis of seven leguminous species growing along Xindian riverbank of Northern Taiwan

    Directory of Open Access Journals (Sweden)

    Cheng-Tai Huang

    2018-01-01

    Full Text Available Legume-rhizobia symbioses of seven leguminous species growing along Xindian riverbank of Northern Taiwan were investigated in this study. These legumes form either determinate or indeterminate types of root nodules. The determinate nodules of Alysicarpus vaginalis, Desmodium. triflorum, D. heterophyllum, Sesbania cannabina and the indeterminate nodules of Mimosa pudica harbored bacteroids of morphological uniformity (length of 1-3 μm, while the indeterminate nodules of Crotalaria zanzibarica and Trifolium repens contained bacteroids of highly pleomorphism (size varying from 1 to 5 μm. The enclosed bacteria were isolated from respective nodules, and twenty slow-growing and nine fast-growing rhizobial isolates were recovered. The slow-growing isolates were classified to the genus Bradyrhizobium based on the 16S rRNA sequences, whereas the fast-growing rhizobia comprise four genera, Neorhizobium, Rhizobium, Cupriavidus and Paraburkholderia. Results of stable isotope analyses revealed that the seven leguminous species had similar and consistently negative δ15N values in leaves (mean of -1.2 ‰, whereas the values were positive (varying from 3.7 to 7.3 ‰ in the nodules. These values were significantly higher in the indeterminate nodules than those in the determinate ones. In addition, variations in the values of leaf δ13C (varying from -29 to -34‰ among the seven legumes were measured, indicating their photosynthetic water use efficiencies were different. This is the first field survey to report the rhizobial diversity and the nutrient relationships of sympatric legume in Taiwan.

  13. Mode of delivery affects the bacterial community in the newborn gut.

    Science.gov (United States)

    Biasucci, Giacomo; Rubini, Monica; Riboni, Sara; Morelli, Lorenzo; Bessi, Elena; Retetangos, Cristiana

    2010-07-01

    The first colonisation of the intestine is one of the most profound immunological exposures faced by the newborn and it is influenced by external and internal factors. The early composition of human microbiota could have long-lasting metabolic effects and the initial composition of human intestinal bacteria is also known to affect postnatal immune system development, as we are already aware that reduced microbial stimulation during infancy would result in slower postnatal maturation of the immune system and development of an optimal balance between TH1 and TH2-like immunity. Mode of delivery has a major role on the composition of intestinal microbiota in early infancy, as it has been shown that infants born by Caesarean section (CS) have lower numbers of Bifidobacteria and Bacteroides compared with vaginally born infants. We designed a study to investigate the influence of mode of delivery (CS vs. vaginal delivery) on intestinal microbial composition on day 3 of life using PCR-denaturing gradient gel electrophoresis (DGGE) and PCR-temperature gradient gel electrophoresis (TGGE). Both DGGE and TGGE analyses have been used, together with the specific amplifications for 10 Bifidobacterium sp., 3 Ruminococcus sp., and Bacteroides that all have a highly relevant physiological role in the intestinal ecosystem of the newborn. A total of 46 term infants were enrolled in the study, consecutively recruiting all the CS-delivered babies (n=23; 8 males and 15 females) and the immediately following spontaneously delivered babies (n=23; 11 males and 12 females). DGGE analysis carried out with Bifidobacterium-specific primers revealed the presence of this genus in 13 of 23 (56.5%) samples derived from vaginally delivered newborns but in none of the samples obtained from newborns delivered by CS. PCR analysis with Bifidobacterium-species-specific primers showed that naturally delivered infants had a large number of bifidobacterial species, whereas in CS-delivered babies only two

  14. Microbial Health Risks Associated with Exposure to Stormwater in a Water Plaza

    Science.gov (United States)

    Sales-Ortells, Helena; Medema, Gertjan

    2015-04-01

    Climate change scenarios predict an increase of intense rainfall events in summer in Western Europe. Current urban drainage systems cannot cope with such intense precipitation events. Cities are constructing local stormwater storage facilities to prevent pluvial flooding. Combining storage with other functions, such as recreation, may lead to exposure to contaminants. This study assessed the microbial quality of rainwater collected in a water plaza in Rotterdam (The Netherlands) and the health risks associated with recreational exposure. The water plaza collects street run-off, diverges first flush to the sewer system and stores the rest of the run-off in the plaza as open water. A rain simulation experiment was conducted using drinking water from fire hydrants. The water flowed over the street pavement into the street gutters and into the square. Samples were collected from the first flush diverted water and from two different levels of the water plaza at different points in time. Campylobacter spp., Cryptosporidium, and Legionella pneumophila were the pathogens investigated, using quantitative PCR. Escherichia coli was quantified with culture methods to obtain information on faecal contamination. Microbial source tracking tools (human Bacteroides, avian Helicobacter and canine mitochondrial DNA, all analysed with quantitative PCR) were used to determine the origin (human, animal) of the intestinal pathogens. To estimate the health risks for children playing in the water plaza after a rain event, a quantitative microbial risk assessment model was built. The volume of water ingested was obtained from literature on similar locations (flooded streets). Published dose-response models were used to calculate the risk per event. Exposure frequency was estimated using weather data (precipitation events). E. coli concentrations were below the level for excellent bathing water in the EU Bathing Water Directive. Cryptosporidium was not found in any sample. Campylobacter spp

  15. Occurrence of H2-Uptake Hydrogenases in Bradyrhizobium sp. (Lupinus) and Their Expression in Nodules of Lupinus spp. and Ornithopus compressus1

    Science.gov (United States)

    Murillo, Jesús; Villa, Ana; Chamber, Manuel; Ruiz-Argüeso, Tomás

    1989-01-01

    Fifty-four strains of Bradyrhizobium sp. (Lupinus) from worldwide collections were screened by a colony hybridization method for the presence of DNA sequences homologous to the structural genes of the Bradyrhizobium japonicum hydrogenase. Twelve strains exhibited strong colony hybridization signals, and subsequent Southern blot hybridization experiments showed that they fell into two different groups on the basis of the pattern of EcoRI fragments containing the homology to the hup probe. All strains in the first group (UPM860, UPM861, and 750) expressed uptake hydrogenase activity in symbiosis with Lupinus albus, Lupinus angustifolius, Lupinus luteus, and Ornithopus compressus, but both the rate of H2 uptake by bacteroids and the relative efficiency of N2 fixation (RE = 1 - [H2 evolved in air/acetylene reduced]) by nodules were markedly affected by the legume host. L. angustifolius was the less permissive host for hydrogenase expression in symbiosis with the three strains (average RE = 0.76), and O. compressus was the more permissive (average RE = 1.0). None of the strains in the second group expressed hydrogenase activity in lupine nodules, and only one exhibited low H2-uptake activity in symbiosis with O. compressus. The inability of these putative Hup+ strains to induce hydrogenase activity in lupine nodules is discussed on the basis of the legume host effect. Among the 42 strains showing no homology to the B. japonicum hup-specific probe in the colony hybridization assay, 10 were examined in symbiosis with L. angustifolius. The average RE for these strains was 0.51. However, one strain, IM43B, exhibited high RE values (higher than 0.80) and high levels of hydrogenase activity in symbiosis with L. angustifolius, L. albus, and L. luteus. In Southern blot hybridization experiments, no homology was detected between the B. japonicum hup-specific DNA probe and total DNA from vegetative cells or bacteroids from strain IM43B even under low stringency hybridization

  16. Modificação da microbiota associada às lesões peridentárias da "cara inchada" em bezerros transferidos para área indene

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    Dutra Iveraldo S.

    2000-01-01

    Full Text Available Observações sobre a epizootiologia da "cara inchada" dos bovinos (CI indicam que animais clinicamente positivos se recuperam espontâneamente quando transferidos para área indene. No presente estudo, 13 bovinos com lesões peridentárias progressivas da "cara inchada" foram transferidos para área indene com a finalidade de se verificar a evolução clínica da doença e a composição da microbiota da bolsa peridentária em duas situações distintas: (1 nas lesões progressivas e (2 quando da recuperação clínica. O estudo bacteriológico semi-quantitativo e qualitativo foi realizado tendo como referência a percentagem de Bacteroides pigmentados de negro presentes nos cultivos. Nas lesões progressivas a percentagem média destes microrganismos foi de 71,3%. Após 4 a 7 meses da transferência os animais se recuperaram espontaneamente, observando-se uma melhora na condição nutricional, desaparecimento do abaulamento facial e do odor fétido bucal e cicatrização com epitelização das lesões peridentárias. Na avaliação da composição da micro-biota das bolsas peridentárias dos bezerros quando clinicamente recuperados, este mesmo grupo de micorganismos representou em média 1,7%. Os resultados revelaram a ocorrência de uma predominância de Bacteroides pigmentados de negro nas lesões peridentárias progressivas da "cara inchada"e sua remissão quantitativa percentual após a recuperação clínica dos animais, consubstanciando as evidências de sua natureza infecciosa primária.

  17. Population level of microbiota in colon of brestfed infants with acute colienteritis

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    D. V. Rotar

    2017-06-01

    Full Text Available Introduction: Despite the undeniable successes in the study of etiology and pathogenesis of acute intestinal infections in children made in recent decades, unfortunately, its’ result does not guarantee clear determination of etiology and mechanisms of development of the disease. This makes impossible to conduct a successful therapy and prevention. Aim: To determine the quantitative changes of microbiome in colon cavity in breastfed infants suffering from colienteritis. Material and methods: Content of colon cavity of 48 children (one to six months old suffered from colienteritis, which was studied with microbiological examination (control group – 35 samples of colon content of practically healthy children. Results: It was revealed that population level of Bifidobacteria in colon cavity in breastfed infants suffering from colienteritis reaches 10.87±0.79 lg CFU/g, Lactobacilli is lower by 12.29 %, Bacteroides – 51.39 %, Escherichia - by 36.39 %. This leads to the contamination of colon with pathogenic E. coli Hly+ in 27.08 % (7.79±0.27 lg CFU/g. Smaller (6.50±0.22 lg CFU/g population level is found in enteropathogenic Escherichia that contaminate biotope in 29.17 % of patients. There is experiencing elevation of population level of Staphylococci by 2.10 times and colonization of the biotope by pathogenic Escherichia (E. coli Hly+, EPEC and conditionally pathogenic Enterobacteria (Proteus spp., C. diversus, Peptococus. The results demonstrated that in majority of sick children there is formation of dysbacteriosis of I stage, and in other one (35.41 % - II-III stages. Conclusions: Acute colienteritis in one to six months old children, who are bestfeded, develops on the background of prevailing colon dysbiosis of I – III stages. This disturbancy is formed by reducing the number of Bifidobacteria and Lactobacilli and the contamination of colon with E. coli Hly +, enteropathogenic Escherichia and C. diversus, Proteus spp., Peptococi

  18. Clinical Pharmacokinetics of Levornidazole in Elderly Subjects and Dosing Regimen Evaluation Using Pharmacokinetic/Pharmacodynamic Analysis.

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    Guo, Beining; He, Gaoli; Wu, Xiaojie; Yu, Jicheng; Cao, Guoying; Li, Yi; Fan, Yaxin; Chen, Yuancheng; Shi, Yaoguo; Zhang, Yingyuan; Zhang, Jing

    2017-07-01

    Levornidazole, the levo-isomer of ornidazole, is a third-generation nitroimidazole derivative newly developed after metronidazole, tinidazole, and ornidazole. An open-label, parallel-controlled, single-dose study was conducted for the investigation of the pharmacokinetic (PK) profile of levornidazole and its metabolites in healthy elderly Chinese subjects, and for the evaluation of 2 dosing regimens in the elderly. Levornidazole was intravenously administered at 500 mg to healthy elderly (aged 60-80 years) or young subjects (aged 19-45 years). The PK profiles of levornidazole and its metabolites in elderly subjects were evaluated and compared with those in the young group. WinNonlin software was used for simulating the PK profile of levornidazole in the elderly population following the dosing regimens of 500 mg BID and 750 mg once daily for 7 days. Monte Carlo simulation was used for estimating the cumulative fraction of response and probability of target attainment of both dosing regimens against Bacteroides spp. The C max , AUC 0-24, and AUC 0-∞ values of levornidazole in the elderly group were 11.98 μg/mL, 131.36 μg·h/mL, and 173.61 μg·h/mL, respectively. The t 1/2 , CL t , and mean residence time from time 0 to infinity were 12.21 hours, 2.91 L/h, and 16.46 hours. The metabolic ratios of metabolites (M) 1, 2, 4, and 6 were 90% against B fragilis and other Bacteroides spp, and the probability of target attainment was >90% when the minimum inhibitory concentration was ≤1 μg/mL, in both groups. No dosing regimen adjustment is suggested when levornidazole is used in elderly patients with normal hepatic functioning and mild renal dysfunction. The findings from the PK/PD analysis imply that both regimens may achieve satisfactory clinical and microbiological efficacy against anaerobic infections in elderly patients. Chinese Clinical Trial Registry (http://www.chictr.org.cn) identifier: ChiCTR-OPC-16007938. Copyright © 2017 Elsevier HS Journals, Inc. All

  19. Ileal microbiota of growing pigs fed different dietary calcium phosphate levels and phytase content and subjected to ileal pectin infusion.

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    Metzler-Zebeli, B U; Vahjen, W; Baumgärtel, T; Rodehutscord, M; Mosenthin, R

    2010-01-01

    Two experiments with growing pigs were conducted to determine the effects of dietary P and Ca levels, phytase supplementation, and ileal pectin infusion on changes in bacterial populations in the ileum and on ileal and fecal fermentation patterns. Growing pigs (BW 30.1 +/- 1.3 kg) were fitted with simple T-cannulas at the distal ileum and were fed a low-P corn-soybean meal control diet (3 g of P/kg), or the control diet supplemented with either 15 g of monocalcium phosphate (MCP)/kg (Exp. 1) or 1,000 phytase units of phytase/kg (Exp. 2). Daily infusion treatments consisted of either 60 g of pectin dissolved in 1.8 L of demineralized water or 1.8 L of demineralized water as a control infusion, infused via the ileal cannula. In each experiment, 8 barrows were assigned to 4 dietary treatments according to a double incomplete 4 x 2 Latin square design. The dietary treatments in Exp. 1 were the control diet with water infusion, the control diet with pectin infusion, the MCP diet with water infusion, or the MCP diet with pectin infusion. In Exp. 2, the pigs received the same control treatments as in Exp. 1 and the phytase diet in combination with water or pectin infusion. Gene copy numbers of total bacteria, Lactobacillus spp., Lactobacillus reuteri, Lactobacillus amylovorus/Lactobacillus sobrius, Lactobacillus mucosae, Enterococcus spp., Enterococcus faecium, Enterococcus faecalis, bifidobacteria, the Clostridium coccoides cluster, the Clostridium leptum cluster, the Bacteroides-Prevotella-Porphyrmonas group, and Enterobacteriaceae were determined by quantitative PCR in DNA extracts of ileal digesta. In Exp. 1, addition of MCP reduced ileal gene copy numbers of Enterococcus spp. (P = 0.048), E. faecium (P = 0.015), and the C. leptum cluster (P = 0.028), whereas pectin infusion enhanced (P = 0.008) ileal d-lactate concentration. In Exp. 2, supplemental phytase led to greater ileal gene copy numbers of the C. coccoides (P = 0.041) and C. leptum (P = 0.048) clusters and

  20. Ontogenesis of the Gut Microbiota Composition in Healthy, Full-Term, Vaginally Born and Breast-Fed Infants over the First 3 Years of Life: A Quantitative Bird's-Eye View.

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    Nagpal, Ravinder; Tsuji, Hirokazu; Takahashi, Takuya; Nomoto, Koji; Kawashima, Kazunari; Nagata, Satoru; Yamashiro, Yuichiro

    2017-01-01

    Early-life intestinal microbiota development is crucial for host's long-term health and is influenced by many factors including gestational age, birth and feeding modes, birth environment, ethnic/geographical background, etc. However, 'quantitative' data on the actual population levels of gut bacterial communities when these influences are controlled for is relatively rare. Herein, we demonstrate a quantitative perspective of microbiota development in natural and healthy milieus, i.e., in healthy, full-term, vaginally born and breast-fed infants ( n = 19) born at same clinic. Fecal microbiota at age 1 and 7 days, 1, 3, and 6 months and 3 years is quantified using highly sensitive reverse-transcription-quantitative-PCR assays targeting bacterial rRNA molecules. At day 1, we detect one or more bacteria in all (100%) of the babies, wherein the microbiota is composed mainly of enterobacteria (35%), Bacteroides fragilis group (23%), enterococci (18%), staphylococci (13%), and bifidobacteria (9%). Altogether, facultative anaerobes predominate during first few weeks whereafter obligate anaerobes including bifidobacteria, B. fragilis group, Clostridium coccoides group, and Clostridium leptum subgroup gradually start prevailing. At 3 years, the composition is represented almost entirely (99%) by obligate anaerobes including C. leptum subgroup (34%), bifidobacteria (22%), B. fragilis group (21%), C. coccoides group (17%), Atopobium cluster (4%), and Prevotella (1%). The overall obligate/facultative proportion is 32/68, 37/63, 54/46, 70/30, 64/36, and 99/1% at 1 and 7 days, 1, 3, and 6 months and 3 years, respectively. However, interestingly, considerable individual-specific variations in the obligate/facultative ratios as well as in the proportions of Firmicutes, Bacteroides, Actinobacteria, and Proteobacteria communities are seen among these babies. This disparity even within this highly homogenous cohort manifests the magnitude of diverse patterns of gut microbiota

  1. The mode of delivery affects the diversity and colonization pattern of the gut microbiota during the first year of infants' life: a systematic review.

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    Rutayisire, Erigene; Huang, Kun; Liu, Yehao; Tao, Fangbiao

    2016-07-30

    The human gut is the habitat for diverse and dynamic microbial ecosystem. The human microbiota plays a critical role in functions that sustain health and is a positive asset in host defenses. Establishment of the human intestinal microbiota during infancy may be influenced by multiple factors including delivery mode. Present review compiles existing evidences on the effect of delivery mode on the diversity and colonization pattern of infants gut microbiota. Two investigators searched for relevant scientific publications from four databases (Pubmed, Medline, Embase, and Web of Science). The last search was performed on September 21, 2015, using key terms ((delivery mode OR caesarean delivery OR cesarean section OR vaginal delivery) AND (gut microbiota OR gut microbiome OR gut microflora OR intestinal microflora OR microbial diversity) AND (infants OR children)). All included studies described at least two types of gut microbiota in relation to delivery mode (caesarean section vs vaginal delivery) and used fecal samples to detect gut microbiota. Seven out of 652 retrieved studies met inclusion criteria, were included in systematic analysis. Caesarean Section (CS) was associated with both lower abundance and diversity of the phyala Actinobacteria and Bacteroidetes, and higher abundance and diversity of the phylum Firmicute from birth to 3 months of life. At the colonization level, Bifidobacterium, and Bacteroides genera seems to be significantly more frequent in vaginally delivered infants compared with CS delivered. These infants were more colonized by the Clostridium, and Lactobacillus genera. From the reports, it is tempting to say that delivery mode has less effect on colonization and diversity of Bifidobacteria, Bacteroides, Clostridium, and Lactobacillus genera from the age of 6 to 12 months of life. The diversity and colonization pattern of the gut microbiota were significantly associated to the mode of delivery during the first three months of life, however

  2. Taxonomic composition of microbiota of colon in breastfed infants with acute colienteritis

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    L. I. Sydorchuk

    2017-02-01

    Full Text Available Introduction: In recent years, paradoxical situation has been created, that testifies adverse evolution of modern acute intestinal infections, especially in infants and vital prognosis for patients by measure of deep study of this disease in patients, which number is significant and continues to grow, and the prognosis is getting worse. Aim: To define the etiology of colienteritis in infants (1–6 months old, the taxonomic composition of pathogenic and conditionally pathogenic microorganisms. Materials and methods: Content of colon of 48 children (one to six months old with colienteritis underwent bacterial and mycological examination (control group – 35 samples of colon content of practically healthy infants. Results: Etiological structure was determined in 28 (58,33 % of investigations. Consistency index, frequency of occurrence, Margalef species richness, Whittaker species diversity, Simpson and Berger–Parker species dominance indices of bacteria of genera Bifidobacterium, Lactobacillus, Bacteroides and Escherichia did not differ in patients and healthy children. These indices grow in Peptostreptococci: constancy index – by 78,26 %, frequency of occurrence – by 60,00 %, Margalef species richness index – by 2 times, Whittaker species diversity index – by 97,32 %, Simpson species dominance index – by 3 times and Berger - Parker index – by 65,31 %. These indices also grew in conditionally pathogenic Enterobacteria (Proteus by 82,24 %, by 2 times, by 2,03 times, by 68,18 % respectively. Study of taxonomic composition of colon microbiota in children with acute colienteritis showed widespread contamination of biotope (cavity by pathogenic (E. coli Hly +, enteropathogenic E. coli and conditionally pathogenic (C. diversus, Proteus ssp. Enterobacteria, Staphylococci, Peptococcus. This is accompanied with elimination of bacteria of genus Eubacterium from colon cavity. Conclusions: Acute colienteritis in one to six months old breastfed

  3. Dietary Capsaicin Improves Glucose Homeostasis and Alters the Gut Microbiota in Obese Diabetic ob/ob Mice

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    Jun-Xian Song

    2017-08-01

    Full Text Available Background: The effects of capsaicin on obesity and glucose homeostasis are still controversial and the mechanisms underlying these effects remain largely unknown. This study aimed to investigate the potential relationship between the regulation of obesity and glucose homeostasis by dietary capsaicin and the alterations of gut microbiota in obese diabetic ob/ob mice.Methods: The ob/ob mice were subjected to a normal, low-capsaicin (0.01%, or high-capsaicin (0.02% diet for 6 weeks, respectively. Obesity phenotypes, glucose homeostasis, the gut microbiota structure and composition, short-chain fatty acids, gastrointestinal hormones, and pro-inflammatory cytokines were measured.Results: Both the low- and high-capsaicin diets failed to prevent the increase in body weight, adiposity index, and Lee's obesity index. However, dietary capsaicin at both the low and high doses significantly inhibited the increase of fasting blood glucose and insulin levels. These inhibitory effects were comparable between the two groups. Similarly, dietary capsaicin resulted in remarkable improvement in glucose and insulin tolerance. In addition, neither the low- nor high-capsaicin diet could alter the α-diversity and β-diversity of the gut microbiota. Taxonomy-based analysis showed that both the low- and high-capsaicin diets, acting in similar ways, significantly increased the Firmicutes/Bacteroidetes ratio at the phylum level as well as increased the Roseburia abundance and decreased the Bacteroides and Parabacteroides abundances at the genus level. Spearman's correlation analysis revealed that the Roseburia abundance was negatively while the Bacteroides and Parabacteroides abundances were positively correlated to the fasting blood glucose level and area under the curve by the oral glucose tolerance test. Finally, the low- and high-capsaicin diets significantly increased the fecal butyrate and plasma total GLP-1 levels, but decreased plasma total ghrelin, TNF-α, IL-1

  4. Activity of Telithromycin (HMR 3647) against Anaerobic Bacteria Compared to Those of Eight Other Agents by Time-Kill Methodology†

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    Credito, Kim L.; Ednie, Lois M.; Jacobs, Michael R.; Appelbaum, Peter C.

    1999-01-01

    Time-kill studies examined the activities of telithromycin (HMR 3647), erythromycin A, azithromycin, clarithromycin, roxithromycin, clindamycin, pristinamycin, amoxicillin-clavulanate, and metronidazole against 11 gram-positive and gram-negative anaerobic bacteria. Time-kill studies were carried out with the addition of Oxyrase in order to prevent the introduction of CO2. Macrolide-azalide-ketolide MICs were 0.004 to 32.0 μg/ml. Of the latter group, telithromycin had the lowest MICs, especially against non-Bacteroides fragilis group strains, followed by azithromycin, clarithromycin, erythromycin A, and roxithromycin. Clindamycin was active (MIC ≤ 2.0 μg/ml) against all anaerobes except Peptostreptococcus magnus and Bacteroides thetaiotaomicron, while pristinamycin MICs were 0.06 to 4.0 μg/ml. Amoxicillin-clavulanate had MICs of ≤1.0 μg/ml, while metronidazole was active (MICs, 0.03 to 2.0 μg/ml) against all except Propionibacterium acnes. After 48 h at twice the MIC, telithromycin was bactericidal (≥99.9% killing) against 6 strains, with 99% killing of 9 strains and 90% killing of 10 strains. After 24 h at twice the MIC, 90, 99, and 99.9% killing of nine, six, and three strains, respectively, occurred. Lower rates of killing were seen at earlier times. Similar kill kinetics relative to the MIC were seen with other macrolides. After 48 h at the MIC, clindamycin was bactericidal against 8 strains, with 99 and 90% killing of 9 and 10 strains, respectively. After 24 h, 90% killing of 10 strains occurred at the MIC. The kinetics of clindamycin were similar to those of pristinamycin. After 48 h at the MIC, amoxicillin-clavulanate showed 99.9% killing of seven strains, with 99% killing of eight strains and 90% killing of nine strains. At four times the MIC, metronidazole was bactericidal against 8 of 10 strains tested after 48 h and against all 10 strains after 24 h; after 12 h, 99% killing of all 10 strains occurred. PMID:10428930

  5. High molecular weight barley β-glucan alters gut microbiota toward reduced cardiovascular disease risk

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    Yanan eWang

    2016-02-01

    Full Text Available The physiological cholesterol-lowering benefits of β-glucan have been well documented, however, whether modulation of gut microbiota by β-glucan is associated with these physiological effects remains unknown. The objectives of this study were therefore to determine the impact of β-glucan on the composition of gut microbiota in mildly hypercholesterolemic individuals and to identify if the altered microbiota are associated with bioactivity of β-glucan in improving risk factors of cardiovascular disease (CVD. Using a randomized, controlled crossover study design, individuals received for 5-week either a treatment breakfast containing 3g high molecular weight (HMW, 3g low molecular weight (LMW, 5g LMW barley β-glucan or wheat and rice (WR. The American Heart Association (AHA diet served as the background diet for all treatment groups. Phases were separated by 4-week washout periods. Fecal samples were collected at the end of each intervention phase and subjected to Illumina sequencing of 16S rRNA genes. Results revealed that at the phylum level, supplementation of 3g/d HMW β-glucan increased Bacteroidetes and decreased Firmicutes abundances compared to control (P < 0.001. At the genus level, consumption of 3g/d HMW β-glucan increased Bacteroides (P < 0.003, tended to increase Prevotella (P < 0.1 but decreased Dorea (P < 0.1, whereas diets containing 5g LMW β-glucan and 3g LMW β-glucan failed to alter the gut microbiota composition. Bacteroides, Prevotella, and Dorea composition correlated (P < 0.05 with shifts of CVD risk factors, including body mass index, waist circumference, blood pressure, as well as triglyceride levels. Our data suggest that consumption of HMW β-glucan favourably alters the composition of the gut microbiota and this altered microbiota profile associates with a reduction of CVD risk markers. Together, our study suggests that β-glucan induced shifts in gut microbiota in a MW-dependent manner and that might be one of

  6. Clinical characteristics and antimicrobial susceptibilities of anaerobic bacteremia in an acute care hospital.

    Science.gov (United States)

    Tan, Thean Yen; Ng, Lily Siew Yong; Kwang, Lee Ling; Rao, Suma; Eng, Li Ching

    2017-02-01

    This study investigated the clinical features of anaerobic bacteraemia in an acute-care hospital, and evaluated the antimicrobial susceptibility of these isolates to commonly available antibiotics. Microbiological and epidemiological data from 2009 to 2011were extracted from the laboratory information system and electronic medical records. One hundred and eleven unique patient episodes consisting of 116 anaerobic isolates were selected for clinical review and antibiotic susceptibility testing. Susceptibilities to amoxicillin-clavulanate, clindamycin, imipenem, metronidazole, moxifloxacin, penicillin and piperacillin-tazobactam were performed using Etest strips with categorical interpretations according to current CLSI breakpoints. Metronidazole-resistant and carbapenem-resistant anaerobic Gram-negative bacilli were screened for the nim and cfiA genes. Clinical data was obtained retrospectively from electronic medical records. During the 3 year period, Bacteroides fragilis group (41%), Clostridium species (14%), Propionibacterium species (9%) and Fusobacterium species (6%) were the most commonly isolated anaerobes. Patients with anaerobic bacteraemia that were included in the study were predominantly above 60 years of age, with community-acquired infections. The most commonly used empiric antibiotic therapies were beta-lactam/beta-lactamase inhibitor combinations (44%) and metronidazole (10%). The crude mortality was 25%, and appropriate initial antibiotic therapy was not significantly associated with improved survival. Intra-abdominal infections (39%) and soft-tissue infections (33%) accounted for nearly three-quarters of all bacteraemia. Antibiotics with the best anaerobic activity were imipenem, piperacillin-tazobactam, amoxicillin-clavulanate and metronidazole, with in-vitro susceptibility rates of 95%, 95%, 94% and 92% respectively. Susceptibilities to penicillin (31%), clindamycin (60%) and moxifloxacin (84%) were more variable. Two multidrug

  7. Integrated analysis of water quality parameters for cost-effective faecal pollution management in river catchments.

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    Nnane, Daniel Ekane; Ebdon, James Edward; Taylor, Huw David

    2011-03-01

    In many parts of the world, microbial contamination of surface waters used for drinking, recreation, and shellfishery remains a pervasive risk to human health, especially in Less Economically Developed Countries (LEDC). However, the capacity to provide effective management strategies to break the waterborne route to human infection is often thwarted by our inability to identify the source of microbial contamination. Microbial Source Tracking (MST) has potential to improve water quality management in complex river catchments that are either routinely, or intermittently contaminated by faecal material from one or more sources, by attributing faecal loads to their human or non-human sources, and thereby supporting more rational approaches to microbial risk assessment. The River Ouse catchment in southeast England (U.K.) was used as a model with which to investigate the integration and application of a novel and simple MST approach to monitor microbial water quality over one calendar year, thereby encompassing a range of meteorological conditions. A key objective of the work was to develop simple low-cost protocols that could be easily replicated. Bacteriophages (viruses) capable of infecting a human specific strain of Bacteroides GB-124, and their correlation with presumptive Escherichia coli, were used to distinguish sources of faecal pollution. The results reported here suggest that in this river catchment the principal source of faecal pollution in most instances was non-human in origin. During storm events, presumptive E. coli and presumptive intestinal enterococci levels were 1.1-1.2 logs higher than during dry weather conditions, and levels of the faecal indicator organisms (FIOs) were closely associated with increased turbidity levels (presumptive E. coli and turbidity, r = 0.43). Spatio-temporal variation in microbial water quality parameters was accounted for by three principal components (67.6%). Cluster Analysis, reduced the fourteen monitoring sites to six

  8. In vitroinvestigation of orange fleshed sweet potato prebiotic potential and its implication on human gut health

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    Mary N.Muchiri

    2017-10-01

    Full Text Available Background: Some food ingredients (prebiotics have been shown to promote a healthy gut by selectively stimulating growth/activity of beneficial gastrointestinal microbes and metabolites such as short chain fatty acids (SCFA while inhibiting pathogens. Orange fleshed sweet potato (Ipomoea batatas Lam; OFSP root tuber is a starchy tropical crop and highly nutritious in terms of pro-vitamin A (beta carotene, dietary fibre, and natural sugars, with negligible amount of fats and cholesterol. Purpose of study: The aim of the study was to investigate using simulated human gut system whether OFSP may have prebiotic activity derived from their fibre, resistant starch, and/or the sugars. Methodology: In vitro pH controlled stirred batch culture fermentation system was used to compare the effect on human gut microbiota of four substrates: two varieties of OFSP (SPK 004 and Tainung, FOS and sucrose known for positive prebiotic and non-selective change respectively. The system was inoculated with faecal slurry from six different human healthy donors from different ethical backgrounds, age, and the effectual change recorded over 24 hours by monitoring bacterial counts (total bacteria, Bacteroides and Bifidobacterium using qPCR molecular technique and SCFA profiles by gas chromatography. Results: The total bacteria count increased by (0.92-1.7 log10 and Bacteroides genus (1.03-1.8 log10 throughout the experimental period but with no significant differences (p<0.05 between the four substrates. However, there were significant differences (p<0.05 in the beneficial Bifidobacterium (1.66-2.66 log10 between the 2 varieties of OFSP and the two controls (FOS and sucrose. The levels of SCFA increased, with acetate as the predominant acid and lactic acid being the least. The OFSP purees elicited high butyric acid levels, which were comparable to those of positive control FOS. Conclusions: The study demonstrated that OFSP purees may have prebiotic potential that can

  9. Comparative evaluation of antimicrobial action of MTA, calcium hydroxide and Portland cement Avaliação comparativa da ação antimicrobiana do MTA, hidróxido de cálcio e cimento Portland

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    Caroline Sousa Ribeiro

    2006-10-01

    Full Text Available The present study aimed to evaluate and compare the antimicrobial effect of MTA Dentsply, MTA Angelus, Calcium Hydroxide and Portland cement. Four reference bacterial strains were used: Pseudomonas aeruginosa, Escherichia coli, Bacteroides fragilis, and Enterococcus faecalis. Plates containing Mueller-Hinton agar supplemented with 5% sheep blood, hemin, and menadione were inoculated with the bacterial suspensions. Subsequently, wells were prepared and immediately filled with materials and incubated at 37ºC for 48 hours under anaerobic conditions, except P. aeruginosa. The diameters of inhibition zones were measured, and data analyzed using ANOVA and the Tukey test with 1% level of significance. MTA Dentsply, MTA Angelus and Portland cement inhibited the growth of P. aeruginosa. Calcium Hydroxide was effective against P. aeruginosa and B. fragillis. Under anaerobic conditions, which may hamper the formation of reactive oxygen species, the materials failed to inhibit E. faecalis, and E. coli.O objetivo do presente trabalho foi avaliar e comparar o efeito antimicrobiano do MTA Dentsply, MTA Angelus, hidróxido de cálcio e cimento Portland sobre quatro cepas bacterianas: Pseudomonas aeruginosa, Escherichia coli, Bacteroides fragilis, e Enterococcus faecalis. Placas contendo agar Muller-Hinton suplementadas com 5% de sangue de carneiro, hemina e menadiona foram inoculadas com as suspensões bacterianas. Poços foram confeccionados com auxílio de perfuradores e imediatamente preenchidos com os materiais, e incubados a 37ºC por 48 horas em atmosfera de anaerobiose, exceto P. aeruginosa. O diâmetro dos halos de inibição foi medido e os dados analisados usando o teste estatístico ANOVA e o de Tukey com nível de significância de 1%. O MTA Dentsply, MTA Angelus e Cimento Portland inibiram o crescimento da P.aeruginosa. O hidróxido de cálcio foi efetivo contra P. aeruginosa e B. fragillis. Sob atmosfera de anaerobiose, condição que pode

  10. Ceftaroline plus Avibactam Demonstrates Bactericidal Activity against Pathogenic Anaerobic Bacteria in a One-Compartment In Vitro Pharmacokinetic/Pharmacodynamic Model

    Science.gov (United States)

    Werth, Brian J.

    2014-01-01

    Anaerobic pathogens are often associated with polymicrobial infections, such as diabetic foot infections. Patients with these infections are often treated with broad-spectrum, multidrug therapies targeting resistant Gram-positive bacteria, such as methicillin-resistant Staphylococcus aureus, as well as Gram-negative bacteria and anaerobes. The broad-spectrum, non-beta-lactam, beta-lactamase inhibitor avibactam has been combined with ceftaroline and may provide a single-product alternative for complicated polymicrobial infections. We compared the activity of ceftaroline-avibactam (CPA) to that of ertapenem (ERT) against common anaerobic pathogens in an in vitro pharmacokinetic/pharmacodynamic (PK/PD) model. Simulations of doses of ceftaroline-fosamil at 600 mg every 8 h (q8h) (maximum free drug concentration [fCmax], 17.04 mg/liter, and half-life [t1/2], 2.66 h) plus avibactam at 600 mg q8h (fCmax, 11.72 mg/liter, and t1/2, 1.8 h) and of ertapenem at 1 g q24h (fCmax, 13 mg/liter, and t1/2, 4 h) were evaluated against two strains of Bacteroides fragilis, one strain of Prevotella bivia, and one strain of Finegoldia magna in an anaerobic one-compartment in vitro PK/PD model over 72 h with a starting inoculum of ∼8 log10 CFU/ml. Bactericidal activity was defined as a reduction of ≥3 log10 CFU/ml from the starting inoculum. Both CPA and ERT were bactericidal against all four strains. CPA demonstrated improved activity against Bacteroides strains compared to that of ERT but had similar activity against Finegoldia magna and P. bivia, although modest regrowth was observed with CPA against P. bivia. No resistance emerged from any of the models. The pharmacokinetics achieved were 92 to 105% of the targets. CPA has potent in vitro activity against common anaerobic pathogens at clinically relevant drug exposures and may be a suitable single product for the management of complicated polymicrobial infections. PMID:24217692

  11. Comparative (metagenomic analysis and ecological profiling of human gut-specific bacteriophage φB124-14.

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    Lesley A Ogilvie

    Full Text Available Bacteriophage associated with the human gut microbiome are likely to have an important impact on community structure and function, and provide a wealth of biotechnological opportunities. Despite this, knowledge of the ecology and composition of bacteriophage in the gut bacterial community remains poor, with few well characterized gut-associated phage genomes currently available. Here we describe the identification and in-depth (metagenomic, proteomic, and ecological analysis of a human gut-specific bacteriophage (designated φB124-14. In doing so we illuminate a fraction of the biological dark matter extant in this ecosystem and its surrounding eco-genomic landscape, identifying a novel and uncharted bacteriophage gene-space in this community. φB124-14 infects only a subset of closely related gut-associated Bacteroides fragilis strains, and the circular genome encodes functions previously found to be rare in viral genomes and human gut viral metagenome sequences, including those which potentially confer advantages upon phage and/or host bacteria. Comparative genomic analyses revealed φB124-14 is most closely related to φB40-8, the only other publically available Bacteroides sp. phage genome, whilst comparative metagenomic analysis of both phage failed to identify any homologous sequences in 136 non-human gut metagenomic datasets searched, supporting the human gut-specific nature of this phage. Moreover, a potential geographic variation in the carriage of these and related phage was revealed by analysis of their distribution and prevalence within 151 human gut microbiomes and viromes from Europe, America and Japan. Finally, ecological profiling of φB124-14 and φB40-8, using both gene-centric alignment-driven phylogenetic analyses, as well as alignment-free gene-independent approaches was undertaken. This not only verified the human gut-specific nature of both phage, but also indicated that these phage populate a distinct and unexplored

  12. Effect of water stress on nitrogen fixation and nodule structure of common bean Efeito do estresse hídrico na fixação biológica de nitrogênio e estrutura de nódulos de feijão

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    Maria Lucrecia Gerosa Ramos

    2003-03-01

    Full Text Available The aim of this work was to investigate the effect of water stress on N2 fixation and nodule structure of two common bean (Phaseolus vulgaris L. cultivars Carioca and EMGOPA-201. Plants were harvested after five and eight days of water stress. Carioca had lower nodule dry weight on both water stress periods; shoot dry weight was lower at five days water stress and did not differ from control after eight days stress. Both cultivars had lower nitrogenase activity than control after five and eight days water stress. For both cultivars, after eight days stress bacteroid membranes were damaged. Carioca presented more pronounced damage to infected tissue, with host cell vacuolation and loss of the peribacteroid membrane at five days after stress; at eight days after stress, there was degradation of cytoplasm host cells and senescence of bacteroids, with their release into intercellular spaces. Intensity of immunogold-labeling of intercellular cortical glycoprotein with the monoclonal antibodies MAC 236/265 was different for both cultivars.O objetivo deste trabalho foi investigar o efeito do estresse hídrico na fixação biológica do N2 e na estrutura dos nódulos de feijão (Phaseolus vulgaris L., nas cultivares Carioca e EMGOPA-201. As plantas foram colhidas após cinco e oito dias de estresse hídrico. A cultivar Carioca apresentou menor peso seco de nódulos que o controle (plantas irrigadas. O peso da parte aérea seca da cultivar Carioca foi menor aos cinco dias de estresse hídrico e não diferiu do controle, após oito dias de estresse. As duas cultivares tiveram menor atividade da nitrogenase após cinco e oito dias de estresse hídrico e apresentaram danos na membrana peribacteróide após oito dias de estresse. A cultivar Carioca foi mais afetada do que a EMGOPA-201, com vacuolação das células e perda da membrana peribacteróide após cinco dias de estresse; aos oito dias, houve degradação das células do citoplasma, senescência e

  13. Additional oligofructose/inulin does not increase faecal bifidobacteria in critically ill patients receiving enteral nutrition: a randomised controlled trial.

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    Majid, Hazreen A; Cole, Jayne; Emery, Peter W; Whelan, Kevin

    2014-12-01

    Patients with diarrhoea during enteral nutrition (EN) have been shown to have low faecal bifidobacteria concentrations. Oligofructose/inulin selectively stimulate the growth of bifidobacteria in healthy humans. This study investigates the effect of additional oligofructose/inulin on the gastrointestinal microbiota, short-chain fatty acids (SCFA) and faecal output in patients receiving EN. Adult patients in the intensive care unit (ICU) who were starting EN with a formula containing fibre were randomised to receive 7 g/d of additional oligofructose/inulin or an identically packaged placebo (maltodextrin). A fresh faecal sample was collected at baseline and following at least 7 days of supplementation. Faecal microbiota were analysed using fluorescent in-situ hybridisation and faecal output was monitored daily. Twenty-two patients (mean age 71 years) completed at least 7 days of intervention (mean 12 days). At the end of the intervention, there were no significant differences in the concentrations of bifidobacteria between the groups, after adjusting for baseline values (oligofructose/inulin 6.9 + 1.4, placebo 7.8 + 1.3 log10 cells/g dry faeces, P > 0.05), but there were significantly lower concentrations of Faecalibacterium prausnitzii (7.0 + 1.0 vs. 8.4 + 1.3 log10 cells/g, P = 0.01) and Bacteroides-Prevotella (9.1 + 1.0 vs. 9.9 + 0.9 log10 cells/g, P = 0.05) in patients receiving additional oligofructose/inulin. There were no differences in faecal concentrations of any SCFA, secretory IgA, daily faecal score or incidence of diarrhoea between the two groups. Additional oligofructose/inulin did not increase faecal bifidobacteria in critically ill patients receiving EN, although it did result in lower concentrations of F. prausnitzii and Bacteroides-Prevotella. This trial is registered at http://controlled-trials.com. Identifier: ISRCTN06446184. Copyright © 2013 Elsevier Ltd and European Society for Clinical Nutrition and Metabolism. All

  14. Phylogeny and molecular signatures (conserved proteins and indels that are specific for the Bacteroidetes and Chlorobi species

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    Lorenzini Emily

    2007-05-01

    Full Text Available Abstract Background The Bacteroidetes and Chlorobi species constitute two main groups of the Bacteria that are closely related in phylogenetic trees. The Bacteroidetes species are widely distributed and include many important periodontal pathogens. In contrast, all Chlorobi are anoxygenic obligate photoautotrophs. Very few (or no biochemical or molecular characteristics are known that are distinctive characteristics of these bacteria, or are commonly shared by them. Results Systematic blast searches were performed on each open reading frame in the genomes of Porphyromonas gingivalis W83, Bacteroides fragilis YCH46, B. thetaiotaomicron VPI-5482, Gramella forsetii KT0803, Chlorobium luteolum (formerly Pelodictyon luteolum DSM 273 and Chlorobaculum tepidum (formerly Chlorobium tepidum TLS to search for proteins that are uniquely present in either all or certain subgroups of Bacteroidetes and Chlorobi. These studies have identified > 600 proteins for which homologues are not found in other organisms. This includes 27 and 51 proteins that are specific for most of the sequenced Bacteroidetes and Chlorobi genomes, respectively; 52 and 38 proteins that are limited to species from the Bacteroidales and Flavobacteriales orders, respectively, and 5 proteins that are common to species from these two orders; 185 proteins that are specific for the Bacteroides genus. Additionally, 6 proteins that are uniquely shared by species from the Bacteroidetes and Chlorobi phyla (one of them also present in the Fibrobacteres have also been identified. This work also describes two large conserved inserts in DNA polymerase III (DnaE and alanyl-tRNA synthetase that are distinctive characteristics of the Chlorobi species and a 3 aa deletion in ClpB chaperone that is mainly found in various Bacteroidales, Flavobacteriales and Flexebacteraceae, but generally not found in the homologs from other organisms. Phylogenetic analyses of the Bacteroidetes and Chlorobi species is also

  15. Real-time analysis of gut flora in Entamoeba histolytica infected patients of Northern India

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    Verma Anil Kumar

    2012-08-01

    Full Text Available Abstract Background Amebic dysentery is caused by the protozoan parasite Entamoeba histolytica and the ingestion of quadrinucleate cyst of E. histolytica from fecally contaminated food or water initiates infection. Excystation occurs in the lumen of small intestine, where motile and potentially invasive trophozoites germinate from cysts. The ability of trophozoites to interact and digest gut bacteria is apparently important for multiplication of the parasite and its pathogenicity; however the contribution of resident bacterial flora is not well understood. We quantified the population of Bacteroides, Bifidobacterium, Ruminococcus, Lactobacillus, Clostridium leptum subgroup, Clostridium coccoides subgroup, Eubacterium, Campylobacter, Methanobrevibacter smithii and Sulphur reducing bacteria using genus specific primers in healthy (N = 22 vs amebic patients (E. histolytica positive, N = 17 stool samples by Real-time PCR. Results Absolute quantification of Bacteroides (p = .001, Closrtridium coccoides subgroup (p = 0.002, Clostridium leptum subgroup (p = 0.0001, Lactobacillus (p = 0.037, Campylobacter (p = 0.0014 and Eubacterium (p = 0.038 show significant drop in their population however, significant increase in Bifdobacterium (p = 0.009 was observed where as the population of Ruminococcus (p = 0.33 remained unaltered in healthy vs amebic patients (E. histolytica positive. We also report high prevalence of nimE gene in stool samples of both healthy volunteers and amebic patients. No significant decrease in nimE gene copy number was observed before and after the treatment with antiamebic drug. Conclusions Our results show significant alteration in predominant gut bacteria in E. histolytica infected individuals. The frequent episodes of intestinal amoebic dysentery thus result in depletion of few predominant genera in gut that may lead to poor digestion and absorption of food in intestine. It further disturbs

  16. 16S Based Microbiome Analysis from Healthy Subjects' Skin Swabs Stored for Different Storage Periods Reveal Phylum to Genus Level Changes.

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    Klymiuk, Ingeborg; Bambach, Isabella; Patra, Vijaykumar; Trajanoski, Slave; Wolf, Peter

    2016-01-01

    Microbiome research and improvements in high throughput sequencing technologies revolutionize our current scientific viewpoint. The human associated microbiome is a prominent focus of clinical research. Large cohort studies are often required to investigate the human microbiome composition and its changes in a multitude of human diseases. Reproducible analyses of large cohort samples require standardized protocols in study design, sampling, storage, processing, and data analysis. In particular, the effect of sample storage on actual results is critical for reproducibility. So far, the effect of storage conditions on the results of microbial analysis has been examined for only a few human biological materials (e.g., stool samples). There is a lack of data and information on appropriate storage conditions on other human derived samples, such as skin. Here, we analyzed skin swab samples collected from three different body locations (forearm, V of the chest and back) of eight healthy volunteers. The skin swabs were soaked in sterile buffer and total DNA was isolated after freezing at -80°C for 24 h, 90 or 365 days. Hypervariable regions V1-2 were amplified from total DNA and libraries were sequenced on an Illumina MiSeq desktop sequencer in paired end mode. Data were analyzed using Qiime 1.9.1. Summarizing all body locations per time point, we found no significant differences in alpha diversity and multivariate community analysis among the three time points. Considering body locations separately significant differences in the richness of forearm samples were found between d0 vs. d90 and d90 vs. d365. Significant differences in the relative abundance of major skin genera ( Propionibacterium , Streptococcus , Bacteroides , Corynebacterium , and Staphylococcus ) were detected in our samples in Bacteroides only among all time points in forearm samples and between d0 vs. d90 and d90 vs. d365 in V of the chest and back samples. Accordingly, significant differences were

  17. Rhizobial exopolysaccharides: genetic control and symbiotic functions

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    Mazur Andrzej

    2006-02-01

    Full Text Available Abstract Specific complex interactions between soil bacteria belonging to Rhizobium, Sinorhizobium, Mesorhizobium, Phylorhizobium, Bradyrhizobium and Azorhizobium commonly known as rhizobia, and their host leguminous plants result in development of root nodules. Nodules are new organs that consist mainly of plant cells infected with bacteroids that provide the host plant with fixed nitrogen. Proper nodule development requires the synthesis and perception of signal molecules such as lipochitooligosaccharides, called Nod factors that are important for induction of nodule development. Bacterial surface polysaccharides are also crucial for establishment of successful symbiosis with legumes. Sugar polymers of rhizobia are composed of a number of different polysaccharides, such as lipopolysaccharides (LPS, capsular polysaccharides (CPS or K-antigens, neutral β-1, 2-glucans and acidic extracellular polysaccharides (EPS. Despite extensive research, the molecular function of the surface polysaccharides in symbiosis remains unclear. This review focuses on exopolysaccharides that are especially important for the invasion that leads to formation of indetermined (with persistent meristem type of nodules on legumes such as clover, vetch, peas or alfalfa. The significance of EPS synthesis in symbiotic interactions of Rhizobium leguminosarum with clover is especially noticed. Accumulating data suggest that exopolysaccharides may be involved in invasion and nodule development, bacterial release from infection threads, bacteroid development, suppression of plant defense response and protection against plant antimicrobial compounds. Rhizobial exopolysaccharides are species-specific heteropolysaccharide polymers composed of common sugars that are substituted with non-carbohydrate residues. Synthesis of repeating units of exopolysaccharide, their modification, polymerization and export to the cell surface is controlled by clusters of genes, named exo/exs, exp or

  18. Real-time analysis of gut flora in Entamoeba histolytica infected patients of Northern India.

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    Verma, Anil Kumar; Verma, Ravi; Ahuja, Vineet; Paul, Jaishree

    2012-08-22

    Amebic dysentery is caused by the protozoan parasite Entamoeba histolytica and the ingestion of quadrinucleate cyst of E. histolytica from fecally contaminated food or water initiates infection. Excystation occurs in the lumen of small intestine, where motile and potentially invasive trophozoites germinate from cysts. The ability of trophozoites to interact and digest gut bacteria is apparently important for multiplication of the parasite and its pathogenicity; however the contribution of resident bacterial flora is not well understood. We quantified the population of Bacteroides, Bifidobacterium, Ruminococcus, Lactobacillus, Clostridium leptum subgroup, Clostridium coccoides subgroup, Eubacterium, Campylobacter, Methanobrevibacter smithii and Sulphur reducing bacteria using genus specific primers in healthy (N = 22) vs amebic patients (E. histolytica positive, N = 17) stool samples by Real-time PCR. Absolute quantification of Bacteroides (p = .001), Closrtridium coccoides subgroup (p = 0.002), Clostridium leptum subgroup (p = 0.0001), Lactobacillus (p = 0.037), Campylobacter (p = 0.0014) and Eubacterium (p = 0.038) show significant drop in their population however, significant increase in Bifdobacterium (p = 0.009) was observed where as the population of Ruminococcus (p = 0.33) remained unaltered in healthy vs amebic patients (E. histolytica positive). We also report high prevalence of nimE gene in stool samples of both healthy volunteers and amebic patients. No significant decrease in nimE gene copy number was observed before and after the treatment with antiamebic drug. Our results show significant alteration in predominant gut bacteria in E. histolytica infected individuals. The frequent episodes of intestinal amoebic dysentery thus result in depletion of few predominant genera in gut that may lead to poor digestion and absorption of food in intestine. It further disturbs the homeostasis between gut epithelium and

  19. Role of Gut Microbiota on Cardio-Metabolic Parameters and Immunity in Coronary Artery Disease Patients with and without Type-2 Diabetes Mellitus

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    Lidia Sanchez-Alcoholado

    2017-10-01

    Full Text Available Gut microbiota composition has been reported as a factor linking host metabolism with the development of cardiovascular diseases (CVD and intestinal immunity. Such gut microbiota has been shown to aggravate CVD by contributing to the production of trimethylamine N-oxide (TMAO, which is a pro-atherogenic compound. Treg cells expressing the transcription factor Forkhead box protein P3 (FoxP3 play an essential role in the regulation of immune responses to commensal microbiota and have an atheroprotective role. However, the aim of this study was to analyze the role of gut microbiota on cardio-metabolic parameters and immunity in coronary artery disease (CAD patients with and without type-2 diabetes mellitus (DM2. The study included 16 coronary CAD-DM2 patients, and 16 age, sex, and BMI matched CAD patients without DM2 (CAD-NDM2. Fecal bacterial DNA was extracted and analyzed by sequencing in a GS Junior 454 platform followed by a bioinformatic analysis (QIIME and PICRUSt. The present study indicated that the diversity and composition of gut microbiota were different between the CAD-DM2 and CAD-NDM2 patients. The abundance of phylum Bacteroidetes was lower, whereas the phyla Firmicutes and Proteobacteria were higher in CAD-DM2 patients than those in the CAD-NDM2 group. CAD-DM2 patients had significantly less beneficial or commensal bacteria (such as Faecalibacterium prausnitzii and Bacteroides fragilis and more opportunistic pathogens (such as Enterobacteriaceae, Streptococcus, and Desulfovibrio. Additionally, CAD-DM2 patients had significantly higher levels of plasma zonulin, TMAO, and IL-1B and significantly lower levels of IL-10 and FOXP3 mRNA expression than CAD-NDM2. Moreover, in the CAD-MD2 group, the increase in Enterobacteriaceae and the decrease in Faecalibacterium prausnitzii were significantly associated with the increase in serum TMAO levels, while the decrease in the abundance of Bacteroides fragilis was associated with the reduction in

  20. Systems biology of bacterial nitrogen fixation: High-throughput technology and its integrative description with constraint-based modeling

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    Resendis-Antonio Osbaldo

    2011-07-01

    Full Text Available Abstract Background Bacterial nitrogen fixation is the biological process by which atmospheric nitrogen is uptaken by bacteroids located in plant root nodules and converted into ammonium through the enzymatic activity of nitrogenase. In practice, this biological process serves as a natural form of fertilization and its optimization has significant implications in sustainable agricultural programs. Currently, the advent of high-throughput technology supplies with valuable data that contribute to understanding the metabolic activity during bacterial nitrogen fixation. This undertaking is not trivial, and the development of computational methods useful in accomplishing an integrative, descriptive and predictive framework is a crucial issue to decoding the principles that regulated the metabolic activity of this biological process. Results In this work we present a systems biology description of the metabolic activity in bacterial nitrogen fixation. This was accomplished by an integrative analysis involving high-throughput data and constraint-based modeling to characterize the metabolic activity in Rhizobium etli bacteroids located at the root nodules of Phaseolus vulgaris (bean plant. Proteome and transcriptome technologies led us to identify 415 proteins and 689 up-regulated genes that orchestrate this biological process. Taking into account these data, we: 1 extended the metabolic reconstruction reported for R. etli; 2 simulated the metabolic activity during symbiotic nitrogen fixation; and 3 evaluated the in silico results in terms of bacteria phenotype. Notably, constraint-based modeling simulated nitrogen fixation activity in such a way that 76.83% of the enzymes and 69.48% of the genes were experimentally justified. Finally, to further assess the predictive scope of the computational model, gene deletion analysis was carried out on nine metabolic enzymes. Our model concluded that an altered metabolic activity on these enzymes induced

  1. Taxonomic structure and population level of colon microbial contents in white rats with experimental thyrotoxicosis

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    L.I. Sydorchuk

    2017-08-01

    Full Text Available Background. Production of numerous biologically active compounds and their metabolites by intestinal microflora, interaction with the immune and other systems is of great importance while studying its changes in various diseases, one of which is thyrotoxicosis. So, the purpose of this study was to determine the severity of intestine microbioma disorder in white rats with experimental thyrotoxicosis (ET. Materials and methods. Studies were carried out on 25 mature male white rats (15 — control group, 10 — research group. ET was simulated by intragastric administration of L-thyroxine for 14 days. Under sterile conditions a laparotomy was performed, a section (2–3 cm of the large intestine with its contents was taken. Sterile 0.9% NaCl solution was added to the content. Series of ten-fold dilutions with a concentration of the initial mixture of 10–2 to 10–11 was prepared. From each test tube 0.01 ml was seeded on solid nutrient media with subsequent isolation and identification of microbes according to morphological, tinctorial, cultural and biochemical properties. Results. The results of the study demonstrated that in ET animals the main microbioma is represented by bacteria Bifidobacterium, Lactobacillus, Bacteroides, and also opportunistic enterobacteria (Escherichia, Proteus, Klebsiella, peptococcus, staphylococci and clostridia. This is accompanied by the elimination of Peptostreptococcus, Enterococcus from bacterial biotope and the contamination of K. oxytoca and staphylococci. There was a pronounced deficit of bifidobacteria by 42.81 %, lactobacillus by 22.57 %, normal intestinal bacillus by 16.48 %. By the population level, the coefficient of quantitative dominance and the significance factor, the leading place is occupied by bacteroids, role of which is increased by 21.72 %, and lactobacillus role decreases by 39.31 %, bifidobacteria decreases by 51.48 % and E. coli decreases by 57.49 %. In this case, the role of peptococcus 3

  2. Bacterial vaginosis, vaginal flora patterns and vaginal hygiene practices in patients presenting with vaginal discharge syndrome in The Gambia, West Africa.

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    Demba, Edward; Morison, Linda; van der Loeff, Maarten Schim; Awasana, Akum A; Gooding, Euphemia; Bailey, Robin; Mayaud, Philippe; West, Beryl

    2005-03-09

    Bacterial vaginosis (BV) - a syndrome characterised by a shift in vaginal flora - appears to be particularly common in sub-Saharan Africa, but little is known of the pattern of vaginal flora associated with BV in Africa. We conducted a study aimed at determining the prevalence of BV and patterns of BV-associated vaginal micro-flora among women with vaginal discharge syndrome (VDS) in The Gambia, West Africa. We enrolled 227 women with VDS from a large genito-urinary medicine clinic in Fajara, The Gambia. BV was diagnosed by the Nugent's score and Amsel's clinical criteria. Vaginal swabs were collected for T vaginalis and vaginal flora microscopy, and for Lactobacillus spp, aerobic organisms, Candida spp and BV-associated bacteria (Gardnerella vaginalis, anaerobic bacteria, and Mycoplasma spp) cultures; and cervical swabs were collected for N gonorrhoeae culture and C trachomatis PCR. Sera were tested for HIV-1 and HIV-2 antibodies. Sexual health history including details on sexual hygiene were obtained by standardised questionnaire. BV prevalence was 47.6% by Nugent's score and 30.8% by Amsel's clinical criteria. Lactobacillus spp were isolated in 37.8% of women, and 70% of the isolates were hydrogen-peroxide (H202)-producing strains. Prevalence of BV-associated bacteria were: G vaginalis 44.4%; Bacteroides 16.7%; Prevotella 15.2%; Peptostretococcus 1.5%; Mobiluncus 0%; other anaerobes 3.1%; and Mycoplasma hominis 21.4%. BV was positively associated with isolation of G vaginalis (odds-ratio [OR] 19.42, 95%CI 7.91 - 47.6) and anaerobes (P = 0.001 [OR] could not be calculated), but not with M hominis. BV was negatively associated with presence of Lactobacillus (OR 0.07, 95%CI 0.03 - 0.15), and H2O2-producing lactobacilli (OR 0.12, 95% CI 0.05 - 0.28). Presence of H2O2-producing lactobacilli was associated with significantly lower prevalence of G vaginalis, anaerobes and C trachomatis. HIV prevalence was 12.8%. Overall, there was no association between BV and HIV, and

  3. [Lactobacillus rhamnosus GG improves symptoms and its mechnism in mice with ovalbumin-induced food allergy].

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    Fang, Shuanfeng; Zhang, Yu; Zhang, Yun; Zhu, Xiaohua; Yie, Bei

    2017-05-01

    Objective To investigate the effect of Lactobacillus rhamnosus GG (LGG) on peripheral blood IL-4/IFN-γ in mice with ovalbumin-induced food allergy. Methods The mice with food allergy were divided into 3 groups (n=10 in each group): food allergy model group, low-dose LGG group (1×10 8 CFU/mL, 200 μL/d) and high-dose LGG group (1×10 9 CFU/mL, 200 μL/d). The healthy mice (n=10) served as a control group. Mice in the LGG groups were given LGG for consecutive 22 days after modeling. The control mice and the food allergy model mice were given normal saline instead of LGG. At day 23, the allergic score, body mass, thymus index, spleen index were recorded and calculated; the expressions of IgE, IL-4 and IFN-γ in peripheral blood were detected by ELISA; the pathological changes of small intestines were observed by HE staining and fecal flora were examined by bacterial culture. Results The thymus and spleen indexes had no significant differences within the 4 groups. Compared with the control group, IL-4, allergic score, E.coli and bacteroides increased, and IFN-γ, IFN-γ/IL-4, IgE, body mass, Bifidobacterium and Lactobacillus decreased in the mice with food allergy. Compared with the mice with food allergy, IL-4, allergic score, E.coli and Bacteroides decreased significantly, and IFN-γ, IFN-γ/IL-4, IgE, body mass, Bifidobacterium and Lactobacillus significantly increased in the LGG groups in a dose-dependent manner. In the food allergy model group, some edematous and necrotic epithelial cells were found in intestinal mucosa. Compared with the food allergy model group, the intestinal mucosa was integrated and the intestinal cells appeared ordered in the LGG groups. Conclusion LGG can remarkably improve the symptoms of ovalbumin-induced food allergy probably by decreasing IL-4/IFN-γ ratio.

  4. Fertilizer and sanitary quality of digestate biofertilizer from the co-digestion of food waste and human excreta.

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    Owamah, H I; Dahunsi, S O; Oranusi, U S; Alfa, M I

    2014-04-01

    This research was aimed at assessing the fertilizer quality and public health implications of using digestate biofertilizer from the anaerobic digestion of food wastes and human excreta. Twelve (12) kg of food wastes and 3kg of human excreta were mixed with water in a 1:1 w/v to make 30-l slurry that was fed into the anaerobic digester to ferment for 60days at mesophilic temperature (22-31°C). Though BOD, COD, organic carbon and ash content in the feedstock were reduced after anaerobic digestion by 50.0%, 10.6%, 74.3% and 1.5% respectively, nitrogen, pH and total solids however increased by 12.1%, 42.5% and 12.4% respectively. The C/N ratios of the feedstock and compost are 135:1 and 15.8:1. The residual total coliforms of 2.10×10(8)CFU/100ml in the digestate was above tolerable limits for direct application on farmlands. Microbial analysis of the digestate biofertilizer revealed the presence of Pseudomonas, Klebsiella, Clostridium, Bacillus, Bacteroides, Penicillum, Salmollena, and Aspergillus. Klebsiella, Bacillus, Pseudomonas, Penicillum and Aspergillus can boost the efficiency of the biofertilizer through nitrogen fixation and nutrient solubility in soils but Klebsiella again and Salmollena are potential health risks to end users. Further treatment of the digestate for more efficient destruction of pathogens is advised. Copyright © 2014 Elsevier Ltd. All rights reserved.

  5. Comparison of Schaedler agar and trypticase soy-yeast extract agar for the cultivation of anaerobic bacteria.

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    Starr, S E; Killgore, G E; Dowell, V R

    1971-10-01

    Schaedler agar (SA) and Trypticase soy-yeast extract agar (TSYEA), both supplemented with rabbit blood (5%, v/v) and menadione (0.5 mg/liter), were compared with respect to quantitative recovery, quality of growth, and rapidity of growth of selected anaerobic bacteria. The media were stored for 2 to 4 days prior to use in an anaerobic glove box, where all subsequent bacteriological procedures were performed. After 24 hr of incubation, colonies of Clostridium cadaveris (C. capitovale), C. haemolyticum, C. novyi A, and C. perfringens were larger on SA than on TSYEA, and the appearance of C. novyi B colonies on SA at 24 hr antedated their appearance on TSYEA. Quantitative recovery of C. novyi B was improved on SA; recovery of the other clostridia tested was comparable on the two media (inconclusive results were obtained with C. novyi A). Rough colonial types of some of the clostridia emerged on SA. No appreciable differences in results with the two media were noted for Bacteroides fragilis, B. melaninogenicus, or Fusobacterium fusiforme.

  6. Microbiology and management of neonatal necrotizing enterocolitis.

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    Brook, Itzhak

    2008-02-01

    Necrotizing enterocolitis (NEC) is a clinical syndrome of ischemic necrosis of the bowel of multiple etiological factors that include the presence of intestinal ischemia, abnormal bacterial flora, and intestinal mucosal immaturity. Numerous reports have implied that the fecal microflora may contribute to the pathogenesis of NEC. A broad range of organisms generally found in the distal gastrointestinal tract have been recovered from the peritoneal cavity and blood of infants with NEC. The predominant organisms include Enterobacteriaceae (i.e., Escherichia coli, Klebsiella pneumoniae) , Clostridium spp., enteric pathogens (salmonellae, Coxsackie B2 virus, coronavirus, rotavirus), and potential pathogens (Bacteroides fragilis). The goals of the initial management is preventing ongoing damage, restoring hemostasis, and minimizing complications. Medical management includes withholding oral feeding, placement of nasogastric tube, abdominal decompression, paracentesis, vigorous intravenous hydration containing electrolytes and calories, support of the circulation, administration of antibiotics, and surveillance for deterioration or complications that require surgical intervention. Indications for surgery include clinical deterioration, perforation, peritonitis, obstruction, and abdominal mass. Prevention remains crucial to decrease the incidence of NEC. Preventive methods include cautious feeding regimens, the use of maternal breast milk, and the use of probiotics.

  7. Microbial diversity in a thermophilic aerobic biofilm process: analysis by length heterogeneity PCR (LH-PCR).

    Science.gov (United States)

    Tiirola, Marja A; Suvilampi, Juhani E; Kulomaa, Markku S; Rintala, Jukka A

    2003-05-01

    A two-stage pilot-scale thermophilic aerobic suspended carrier biofilm process (SCBP) was set up for the on-site treatment of pulp and paper mill whitewater lining. The microbial diversity in this process was analyzed by length heterogeneity analysis of PCR-amplified 16S ribosomal DNA. The primer pair selected for PCR amplification was first evaluated by a computational analysis of fragment lengths in ten main phylogenetical eubacterial groups. The fragment contained the first third of the 16S rRNA gene, which was shown to vary naturally between 465 and 563 bp in length. The length heterogeneity analysis of polymerase chain reaction (LH-PCR) profile of the biomass attached to carrier elements was found to be diverse in both stages of the SCBP. During normal operating conditions, sequences belonging to beta-Proteobacteria, Cytophaga/Flexibacter/Bacteroides group and gamma-Proteobacteria were assigned to the most prominent LH-PCR peak. Samples from the suspended biomass consisted of completely different bacterial populations, which were, however, similar in the serial reactors. The pilot process experienced alkaline shocks, after which Bacillus-like sequences were detected in both the biofilm and suspended biomass. However, when the conditions were reversed, the normal microbial population in the biofilm recovered rapidly without further biomass inoculations. This study shows that LH-PCR is a valuable method for profiling microbial diversity and dynamics in industrial wastewater processes.

  8. Effect of Lactobacillus salivarius Ls-33 on fecal microbiota in obese adolescents.

    Science.gov (United States)

    Larsen, Nadja; Vogensen, Finn K; Gøbel, Rikke Juul; Michaelsen, Kim F; Forssten, Sofia D; Lahtinen, Sampo J; Jakobsen, Mogens

    2013-12-01

    This study is a part of the clinical trials with probiotic bacterium Lactobacillus salivarius Ls-33 conducted in obese adolescents. Previously reported clinical studies showed no effect of Ls-33 consumption on the metabolic syndrome in the subject group. The aim of the study was to investigate the impact of L. salivarius Ls-33 on fecal microbiota in obese adolescents. The study was a double-blinded intervention with 50 subjects randomized to intake of L. salivarius Ls-33 or placebo for 12 weeks. The fecal microbiota was assessed by real-time quantitative PCR before and after intervention. Concentrations of fecal short chain fatty acids were determined using gas chromatography. Ratios of Bacteroides-Prevotella-Porphyromonas group to Firmicutes belonging bacteria, including Clostridium cluster XIV, Blautia coccoides_Eubacteria rectale group and Roseburia intestinalis, were significantly increased (p ≤ 0.05) after administration of Ls-33. The cell numbers of fecal bacteria, including the groups above as well as Clostridium cluster I, Clostridium cluster IV, Faecalibacterium prausnitzii, Enterobacteriaceae, Enterococcus, the Lactobacillus group and Bifidobacterium were not significantly altered by intervention. Similarly, short chain fatty acids remained unaffected. L. salivarius Ls-33 might modify the fecal microbiota in obese adolescents in a way not related to metabolic syndrome. NCT 01020617. Copyright © 2013 Elsevier Ltd and European Society for Clinical Nutrition and Metabolism. All rights reserved.

  9. Humin as an electron donor for enhancement of multiple microbial reduction reactions with different redox potentials in a consortium.

    Science.gov (United States)

    Zhang, Dongdong; Zhang, Chunfang; Xiao, Zhixing; Suzuki, Daisuke; Katayama, Arata

    2015-02-01

    A solid-phase humin, acting as an electron donor, was able to enhance multiple reductive biotransformations, including dechlorination of pentachlorophenol (PCP), dissimilatory reduction of amorphous Fe (III) oxide (FeOOH), and reduction of nitrate, in a consortium. Humin that was chemically reduced by NaBH4 served as an electron donor for these microbial reducing reactions, with electron donating capacities of 0.013 mmol e(-)/g for PCP dechlorination, 0.15 mmol e(-)/g for iron reduction, and 0.30 mmol e(-)/g for nitrate reduction. Two pairs of oxidation and reduction peaks within the humin were detected by cyclic voltammetry analysis. 16S rRNA gene sequencing-based microbial community analysis of the consortium incubated with different terminal electron acceptors, suggested that Dehalobacter sp., Bacteroides sp., and Sulfurospirillum sp. were involved in the PCP dechlorination, dissimilatory iron reduction, and nitrate reduction, respectively. These findings suggested that humin functioned as a versatile redox mediator, donating electrons for multiple respiration reactions with different redox potentials. Copyright © 2014 The Society for Biotechnology, Japan. Published by Elsevier B.V. All rights reserved.

  10. Correlation of intestinal microbiota with overweight and obesity in Kazakh school children

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    Xu Peiru

    2012-11-01

    Full Text Available Abstract Background This study sought to investigate a possible correlation between the intestinal microbiota, Bacteroidetes and Firmicutes, and obesity in Kazakh school children, aged 7–13 (n = 175. Results Obese subjects had significantly greater systolic blood pressure, waist and hip circumference, as well as HOMA-IR as compared to normal and overweight participants. In addition, Bacteroides copy number and Bact/Firm ratios were significantly lower in the obese group as compared to the normal and overweight groups (P Bacteroidetes copy number (r = −0.18, P = 0.017 as well as Bact/Firm (r = −0.22, P = 0.003 was observed. Conclusion An association between reduced gut Bacteroidetes and Bact/Firm ratio with obesity in female Kazakh children was identified. Further studies are necessary to elucidate the mechanism behind these changes as well as the value of determining their presence for predicting obesity.

  11. Intake of Meat Proteins Substantially Increased the Relative Abundance of Genus Lactobacillus in Rat Feces.

    Directory of Open Access Journals (Sweden)

    Yingying Zhu

    Full Text Available Diet has been shown to have a critical influence on gut bacteria and host health, and high levels of red meat in diet have been shown to increase colonic DNA damage and thus be harmful to gut health. However, previous studies focused more on the effects of meat than of meat proteins. In order to investigate whether intake of meat proteins affects the composition and metabolic activities of gut microbiota, feces were collected from growing rats that were fed with either meat proteins (from beef, pork or fish or non-meat proteins (casein or soy for 14 days. The resulting composition of gut microbiota was profiled by sequencing the V4-V5 region of the 16S ribosomal RNA genes and the short chain fatty acids (SCFAs were analyzed using gas chromatography. The composition of gut microbiota and SCFA levels were significantly different between the five diet groups. At a recommended dose of 20% protein in the diet, meat protein-fed rats had a higher relative abundance of the beneficial genus Lactobacillus, but lower levels of SCFAs and SCFA-producing bacteria including Fusobacterium, Bacteroides and Prevotella, compared with the soy protein-fed group. Further work is needed on the regulatory pathways linking dietary protein intake to gut microbiota.

  12. Intake of Meat Proteins Substantially Increased the Relative Abundance of Genus Lactobacillus in Rat Feces.

    Science.gov (United States)

    Zhu, Yingying; Lin, Xisha; Li, He; Li, Yingqiu; Shi, Xuebin; Zhao, Fan; Xu, Xinglian; Li, Chunbao; Zhou, Guanghong

    2016-01-01

    Diet has been shown to have a critical influence on gut bacteria and host health, and high levels of red meat in diet have been shown to increase colonic DNA damage and thus be harmful to gut health. However, previous studies focused more on the effects of meat than of meat proteins. In order to investigate whether intake of meat proteins affects the composition and metabolic activities of gut microbiota, feces were collected from growing rats that were fed with either meat proteins (from beef, pork or fish) or non-meat proteins (casein or soy) for 14 days. The resulting composition of gut microbiota was profiled by sequencing the V4-V5 region of the 16S ribosomal RNA genes and the short chain fatty acids (SCFAs) were analyzed using gas chromatography. The composition of gut microbiota and SCFA levels were significantly different between the five diet groups. At a recommended dose of 20% protein in the diet, meat protein-fed rats had a higher relative abundance of the beneficial genus Lactobacillus, but lower levels of SCFAs and SCFA-producing bacteria including Fusobacterium, Bacteroides and Prevotella, compared with the soy protein-fed group. Further work is needed on the regulatory pathways linking dietary protein intake to gut microbiota.

  13. Effect of dietary porphyran from the red alga, Porphyra yezoensis, on glucose metabolism in diabetic KK-Ay mice.

    Science.gov (United States)

    Kitano, Yuki; Murazumi, Koki; Duan, Jingjing; Kurose, Kosuke; Kobayashi, Shunichi; Sugawara, Tatsuya; Hirata, Takashi

    2012-01-01

    Porphyran (POR) from the red alga Porphyra yezoensis is a water soluble dietary fiber. In this study, we investigated the effect of dietary POR on glucose metabolism in KK-Ay mice (a model for type 2 diabetes). Mice were divided into 4 groups and fed a diet containing 5% cellulose (control), POR, POR Arg or POR K. After 3 wk of feeding, plasma insulin levels and the calculated homeostasis model assessment-insulin resistance (HOMA-IR) index were significantly lower in the POR group than in the control group. Compared with the control group, plasma adiponectin levels were significantly increased in the POR, POR Arg and POR K groups. These results suggest that dietary POR should improve glucose metabolism in diabetes via up-regulation of adiponectin levels. In addition, the amount of propionic acid in the cecum of the POR group was significantly higher than in the control group and the profile of bacterial flora was changed by dietary POR. In the cecum of the POR, POR Arg and POR K groups, Bacteroides was significantly increased and Clostridium coccoides was significantly decreased compared with in the control group. The effects of dietary POR on the hindgut environment might contribute to the improvement of glucose metabolism.

  14. Noninvasive Imaging of Colitis Using Multispectral Optoacoustic Tomography.

    Science.gov (United States)

    Bhutiani, Neal; Grizzle, William E; Galandiuk, Susan; Otali, Denis; Dryden, Gerald W; Egilmez, Nejat K; McNally, Lacey R

    2017-06-01

    Currently, several noninvasive modalities, including MRI and PET, are being investigated to identify early intestinal inflammation, longitudinally monitor disease status, or detect dysplastic changes in patients with inflammatory bowel disease. Here, we assess the applicability and utility of multispectral optoacoustic tomography (MSOT) in evaluating the presence and severity of colitis. Methods: C57B/6 mice were untreated or treated with Bacteroides fragilis and antibiotic-mediated depletion of intestinal flora to initiate colitis. Mice were imaged using MSOT to detect intestinal inflammation. Intestinal inflammation identified with MSOT was also confirmed using both colonoscopy and histology. Results: Mice with bacterial colitis demonstrated a temporally associated increase in mesenteric and colonic vascularity with an increase in mean signal intensity of oxygenated hemoglobin ( P = 0.004) by MSOT 2 d after inoculation. These findings were significantly more prominent 7 d after inoculation, with increased mean signal intensity of oxygenated hemoglobin ( P = 0.0002) and the development of punctate vascular lesions on the colonic surface, which corresponded to changes observed on colonoscopy as well as histology. Conclusion: With improvements in depth of tissue penetration, MSOT may hold potential as a sensitive, accurate, noninvasive imaging tool in the evaluation of patients with inflammatory bowel disease. © 2017 by the Society of Nuclear Medicine and Molecular Imaging.

  15. The Rhizobium meliloti putA gene: its role in the establishment of the symbiotic interaction with alfalfa.

    Science.gov (United States)

    Jiménez-Zurdo, J I; García-Rodríguez, F M; Toro, N

    1997-01-01

    Little is known about the energy sources used by rhizobia during colonization, invasion and root nodule formation on leguminous plants. We have recently reported that an impaired proline metabolism in rhizobium meliloti leads to a reduced nodulation efficiency and competitiveness on alfalfa roots. In the present study we have characterized the R. meliloti proline dehydrogenase gene (putA) and addressed the question of its role in symbiosis. This rhizobial gene encodes a 1224-amino-acid-long polypeptide which is homologous to enteric bacteria, Rhodobacter capsulatus and Bradyrhizobium japonicum PutA proteins. Like the situation in these bacteria, sequence analysis identified the proline dehydrogenase (PDH) and pyrroline-5-carboxylate dehydrogenase (P5CDH) domains in the R. meliloti putA-encoded protein. Beta-galactosidase assays performed with free-living cells carrying a putA-lacZ transcriptional fusion revealed that R. meliloti putA gene expression is induced by proline, autoregulated by its encoded product, and independent of the general nitrogen regulatory system (Ntr). In addition, analysis of putA expression during the different steps of the symbiotic interaction with alfalfa showed that expression of this gene is turned on by the root exudates (RE), during root invasion and nodule formation, but not in differentiated nitrogen-fixing bacteroids. Furthermore, we show that the PutA- phenotype leads to a significant reduction of alfalfa root colonization by R. meliloti.

  16. Comparative Analysis of Glycoside Hydrolases Activities from Phylogenetically Diverse Marine Bacteria of the Genus Arenibacter

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    Valery Mikhailov

    2013-06-01

    Full Text Available A total of 16 marine strains belonging to the genus Arenibacter, recovered from diverse microbial communities associated with various marine habitats and collected from different locations, were evaluated in degradation of natural polysaccharides and chromogenic glycosides. Most strains were affiliated with five recognized species, and some presented three new species within the genus Arenibacter. No strains contained enzymes depolymerizing polysaccharides, but synthesized a wide spectrum of glycosidases. Highly active β-N-acetylglucosaminidases and α-N-acetylgalactosaminidases were the main glycosidases for all Arenibacter. The genes, encoding two new members of glycoside hydrolyses (GH families, 20 and 109, were isolated and characterized from the genomes of Arenibacter latericius. Molecular genetic analysis using glycosidase-specific primers shows the absence of GH27 and GH36 genes. A sequence comparison with functionally-characterized GH20 and GH109 enzymes shows that both sequences are closest to the enzymes of chitinolytic bacteria Vibrio furnissii and Cellulomonas fimi of marine and terrestrial origin, as well as human pathogen Elisabethkingia meningoseptica and simbionts Akkermansia muciniphila, gut and non-gut Bacteroides, respectively. These results revealed that the genus Arenibacter is a highly taxonomic diverse group of microorganisms, which can participate in degradation of natural polymers in marine environments depending on their niche and habitat adaptations. They are new prospective candidates for biotechnological applications due to their production of unique glycosidases.

  17. Comparative Analysis of Glycoside Hydrolases Activities from Phylogenetically Diverse Marine Bacteria of the Genus Arenibacter

    Science.gov (United States)

    Bakunina, Irina; Nedashkovskaya, Olga; Balabanova, Larissa; Zvyagintseva, Tatyana; Rasskasov, Valery; Mikhailov, Valery

    2013-01-01

    A total of 16 marine strains belonging to the genus Arenibacter, recovered from diverse microbial communities associated with various marine habitats and collected from different locations, were evaluated in degradation of natural polysaccharides and chromogenic glycosides. Most strains were affiliated with five recognized species, and some presented three new species within the genus Arenibacter. No strains contained enzymes depolymerizing polysaccharides, but synthesized a wide spectrum of glycosidases. Highly active β-N-acetylglucosaminidases and α-N-acetylgalactosaminidases were the main glycosidases for all Arenibacter. The genes, encoding two new members of glycoside hydrolyses (GH) families, 20 and 109, were isolated and characterized from the genomes of Arenibacter latericius. Molecular genetic analysis using glycosidase-specific primers shows the absence of GH27 and GH36 genes. A sequence comparison with functionally-characterized GH20 and GH109 enzymes shows that both sequences are closest to the enzymes of chitinolytic bacteria Vibrio furnissii and Cellulomonas fimi of marine and terrestrial origin, as well as human pathogen Elisabethkingia meningoseptica and simbionts Akkermansia muciniphila, gut and non-gut Bacteroides, respectively. These results revealed that the genus Arenibacter is a highly taxonomic diverse group of microorganisms, which can participate in degradation of natural polymers in marine environments depending on their niche and habitat adaptations. They are new prospective candidates for biotechnological applications due to their production of unique glycosidases. PMID:23752354

  18. Determination of fecal contamination origin in reclaimed water open-air ponds using biochemical fingerprinting of enterococci and fecal coliforms.

    Science.gov (United States)

    Casanovas-Massana, Arnau; Blanch, Anicet R

    2013-05-01

    Low levels of fecal indicator bacteria (FIB) were recently detected in two reclaimed water open-air ponds used to irrigate a golf course located in Northeastern Spain. The aim of this study was to evaluate the feasibility of a biochemical fingerprinting method to track the origin of fecal contamination in water with low FIB levels, as in the aforementioned ponds. We also aimed to determine whether FIB presence was due to regrowth of the reclaimed water populations or to a contribution of fecal matter whose source was in the golf facility. Three hundred and fifty enterococcal strains and 308 fecal coliform strains were isolated from the ponds and reclamation plant, and they were biochemically phenotyped. In addition, the inactivation of several microbial fecal pollution indicators (fecal coliforms, total bifidobacteria, sorbitol-fermenting bifidobacteria, somatic bacteriophages, and bacteriophages infecting Bacteroides thetaiotaomicron) was studied using a mesocosm in situ in order to obtain information about their decay rate. Although FIB concentration was low, the biochemical fingerprinting provided evidence that the origin of the fecal contamination in the ponds was not related to the reclaimed water. Biochemical fingerprinting thus proved to be a successful approach, since other microbial source-tracking methods perform poorly when dealing with low fecal load matrices. Furthermore, the mesocosm assays indicated that none of the microbial fecal indicators was able to regrow in the ponds. Finally, the study highlights the fact that reclaimed water may be recontaminated in open-air reservoirs, and therefore, its microbial quality should be monitored throughout its use.

  19. Lactobacillus rhamnosus R11 consumed in a food supplement survived human digestive transit without modifying microbiota equilibrium as assessed by real-time polymerase chain reaction.

    Science.gov (United States)

    Firmesse, Olivier; Mogenet, Agnès; Bresson, Jean-Louis; Corthier, Gérard; Furet, Jean-Pierre

    2008-01-01

    The aim of this study was to evaluate the survival of Lactobacillus rhamnosus R11 and Lactobacillus acidophilus R52 in the human digestive tract and their effects on the microbiota homeostasis. We designed an open human trial including 14 healthy volunteers. A 3-week exclusion period of fermented products was followed by a 12-day consumption period of 4 capsules daily containing 2 x 10(9)L. rhamnosus R11 and 1 x 10(8)L. acidophilus R52, and a 12-day wash-out period. The 2 strains and dominant bacterial groups of the microbiota were quantified by real-time polymerase chain reaction. At the end of the capsule consumption period, high levels of L. rhamnosus R11 were detected in faecal samples from all volunteers, reaching a mean value of 7.1 log(10) colony-forming unit (CFU) equivalents/g of stool. L. acidophilus R52 was detected in the stools of only 1 volunteer, reaching a maximum level of 6.1 log(10) CFU equivalents/g of stool. Dilution plating enumerations performed in parallel provided less consistent and generally lower levels. No significant effect of capsule consumption was observed on microbiota homeostasis for the dominant faecal populations. Mean values of 8.8, 9.2, 9.9 and 10.6 log(10) CFU equivalents/g of stool were obtained for the Clostridium coccoides, Bifidobacterium sp., Bacteroides sp. and Clostridium leptum groups, respectively.

  20. Microcosms for evaluating microbial indicator persistence and mobilization in fluvial sediments during rainfall events.

    Science.gov (United States)

    Martín-Díaz, Julia; García-Aljaro, Cristina; Pascual-Benito, Míriam; Galofré, Belén; Blanch, Anicet R; Lucena, Francisco

    2017-10-15

    Mediterranean rivers, which are subject to long, dry periods and heavy rainfall events, could be particularly useful for understanding future climate scenarios. This study generated microcosms that mimicked riverbank sediment resuspension into the water of a typical Mediterranean river as a consequence of heavy rainfall. The mobilization and inactivation of six fecal pollution indicators and microbial source tracking markers were evaluated. The T 90 values in the sediments were: 4 days for sorbitol-fermenting Bifidobacterium, 11 days for culturable E. coli, 36 days for bacteriophages infecting Bacteroides thetaiotaomicron strain GA17 and more than 42 days for qPCR-detected E. coli, somatic coliphages and sulfite-reducing clostridia spores. Bacteriophages and bacteria showed different resuspension and sedimentation patterns. The data obtained could be used in predictive models to assess the effects of climate change on surface water quality. Pathogen mobilization into the water column poses a risk for humans, animals and the natural environment, and breaches the One Health approach. Copyright © 2017 Elsevier Ltd. All rights reserved.

  1. The microbial content of raw and pasteurized cow milk as determined by molecular approaches.

    Science.gov (United States)

    Quigley, Lisa; McCarthy, Robert; O'Sullivan, Orla; Beresford, Tom P; Fitzgerald, Gerald F; Ross, R Paul; Stanton, Catherine; Cotter, Paul D

    2013-08-01

    The microbial composition of raw and pasteurized milk is assessed on a daily basis. However, many such tests are culture-dependent, and, thus, bacteria that are present at subdominant levels, or that cannot be easily grown in the laboratory, may be overlooked. To address this potential bias, we have used several culture-independent techniques, including flow cytometry, real-time quantitative PCR, and high-throughput DNA sequencing, to assess the microbial population of milk from a selection of commercial milk producers, pre- and postpasteurization. The combination of techniques employed reveals the presence of a previously unrecognized and diverse bacterial population in unpasteurized cow milk. Most notably, the use of high-throughput DNA sequencing resulted in several bacterial genera being identified in milk samples for the first time. These included Bacteroides, Faecalibacterium, Prevotella, and Catenibacterium. Our culture-independent analyses also indicate that the bacterial population of pasteurized milk is more diverse than previously appreciated, and that nonthermoduric bacteria within these populations are likely to be in a damaged, nonculturable form. It is thus apparent that the application of state-of-the-art approaches can provide a detailed insight into the bacterial composition of milk and could potentially be employed in the future to investigate the factors that influence the composition of these populations. Copyright © 2013 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

  2. Enrichment of extremophilic exoelectrogens in microbial electrolysis cells using Red Sea brine pools as inocula.

    Science.gov (United States)

    Shehab, Noura A; Ortiz-Medina, Juan F; Katuri, Krishna P; Hari, Ananda Rao; Amy, Gary; Logan, Bruce E; Saikaly, Pascal E

    2017-09-01

    Applying microbial electrochemical technologies for the treatment of highly saline or thermophilic solutions is challenging due to the lack of proper inocula to enrich for efficient exoelectrogens. Brine pools from three different locations (Valdivia, Atlantis II and Kebrit) in the Red Sea were investigated as potential inocula sources for enriching exoelectrogens in microbial electrolysis cells (MECs) under thermophilic (70°C) and hypersaline (25% salinity) conditions. Of these, only the Valdivia brine pool produced high and consistent current 6.8±2.1A/m 2 -anode in MECs operated at a set anode potential of +0.2V vs. Ag/AgCl (+0.405V vs. standard hydrogen electrode). These results show that exoelectrogens are present in these extreme environments and can be used to startup MEC under thermophilic and hypersaline conditions. Bacteroides was enriched on the anode of the Valdivia MEC, but it was not detected in the open circuit voltage reactor seeded with the Valdivia brine pool. Copyright © 2017 Elsevier Ltd. All rights reserved.

  3. Simultaneous delivery of antibiotics neomycin and ampicillin in drinking water inhibits fermentation of resistant starch in rats.

    Science.gov (United States)

    Carvajal-Aldaz, Diana G; Guice, Justin L; Page, Ryan C; Raggio, Anne M; Martin, Roy J; Husseneder, Claudia; Durham, Holiday A; Geaghan, James; Janes, Marlene; Gauthier, Ted; Coulon, Diana; Keenan, Michael J

    2017-03-01

    Antibiotics ampicillin 1 g/L and neomycin 0.5 g/L were added to drinking water before or during feeding of resistant starch (RS) to rats to inhibit fermentation. In a preliminary study, antibiotics and no RS were given prior to rats receiving a transplant of cecal contents via gavage from donor rats fed RS (without antibiotics) or a water gavage before feeding resistant starch to both groups. Antibiotics given prior to feeding RS did not prevent later fermentation of RS regardless of either type of gavage. In the second study, antibiotics were given simultaneously with feeding of RS. This resulted in inhibition of fermentation of RS with cecal contents pH >8 and low amounts of acetate and butyrate. Rats treated with antibiotics had reduced Bifidobacteria spp., but similar Bacteroides spp. to control groups to reduce acetate and butyrate and preserve the production of propionate. Despite reduced fermentation, rats given antibiotics had increased glucagon-like peptide 1 (GLP-1) and cecum size, measures that are usually associated with fermentation. A simultaneous delivery of antibiotics inhibited fermentation of RS. However, increased GLP-1 and cecum size would be confounding effects in assessing the mechanism for beneficial effects of dietary RS by knocking out fermentation. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  4. Comparative in vitro fermentations of cranberry and grape seed polyphenols with colonic microbiota.

    Science.gov (United States)

    Sánchez-Patán, Fernando; Barroso, Elvira; van de Wiele, Tom; Jiménez-Girón, Ana; Martín-Alvarez, Pedro J; Moreno-Arribas, M Victoria; Martínez-Cuesta, M Carmen; Peláez, Carmen; Requena, Teresa; Bartolomé, Begoña

    2015-09-15

    In this study, we have assessed the phenolic metabolism of a cranberry extract by microbiota obtained from the ascending colon and descending colon compartments of a dynamic gastrointestinal simulator (SHIME). For comparison, parallel fermentations with a grape seed extract were carried out. Extracts were used directly without previous intestinal digestion. Among the 60 phenolic compounds targeted, our results confirmed the formation of phenylacetic, phenylpropionic and benzoic acids as well as phenols such as catechol and its derivatives from the action of colonic microbiota on cranberry polyphenols. Benzoic acid (38.4μg/ml), 4-hydroxy-5-(3'-hydroxyphenyl)-valeric acid (26.2μg/ml) and phenylacetic acid (19.5μg/ml) reached the highest concentrations. Under the same conditions, microbial degradation of grape seed polyphenols took place to a lesser extent compared to cranberry polyphenols, which was consistent with the more pronounced antimicrobial effect observed for the grape seed polyphenols, particularly against Bacteroides, Prevotella and Blautia coccoides-Eubacterium rectale. Copyright © 2015 Elsevier Ltd. All rights reserved.

  5. In vitro extraction and fermentation of polyphenols from grape seeds (Vitis vinifera) by human intestinal microbiota.

    Science.gov (United States)

    Zhou, Li; Wang, Wei; Huang, Jun; Ding, Yu; Pan, Zhouqiang; Zhao, Ya; Zhang, Renkang; Hu, Bing; Zeng, Xiaoxiong

    2016-04-01

    The effects of several parameters on the extraction yield of total polyphenols from grape seeds by pressurized liquid extraction were investigated. The highest recovery of total polyphenols occurred at 80 °C within 5 min, and a single extraction allowed a recovery of more than 97% of total polyphenols. Following the purification with macroporous resin, the effects of grape polyphenols (>94.8%) on human intestinal microbiota were monitored over 36 h incubation by fluorescence in situ hybridization, and short-chain fatty acids (SCFAs) were measured by HPLC. The result showed that the grape polyphenols promoted the changes in the relevant microbial populations and shifted the profiles of SCFAs. Fermentation of grape polyphenols resulted in a significant increase in the numbers of Bifidobacterium spp. and Lactobacillus-Enterococcus group and inhibition in the growth of the Clostridium histolyticum group and the Bacteroides-Prevotella group, with no significant effect on the population of total bacteria. The findings suggest that grape polyphenols have potential prebiotic effects on modulating the gut microbiota composition and generating SCFAs that contribute to the improvements of host health.

  6. Assessment of the prebiotic effect of quinoa and amaranth in the human intestinal ecosystem.

    Science.gov (United States)

    Gullón, Beatriz; Gullón, Patricia; Tavaria, Freni K; Yáñez, Remedios

    2016-09-14

    Quinoa and amaranth belong to the group of the so called "superfoods" and have a nutritional composition that confers multiple benefits. In this work, we explored the possibility of these foods exhibiting a prebiotic effect. These pseudocereals were subjected to an in vitro digestion and used as carbon sources in batch cultures with faecal human inocula. The effects on the microbiota composition and their metabolic products were determined by assessment of variations in pH, short-chain fatty acid (SCFA) production and changes in the dynamic bacterial populations by fluorescence in situ hybridization (FISH). After 48 h of incubation, the total SCFAs were 106.5 mM for quinoa and 108.83 mM for amaranth, in line with the decrease in pH. Considerable differences (p < 0.05) were found in certain microbial groups, including Bifidobacterium spp., Lactobacillus-Enterococcus, Atopobium, Bacteroides-Prevotella, Clostridium coccoides-Eubacterium rectale, Faecalibacterium prausnitzii and Roseburia intestinalis. Our research suggests that these pseudocereals can have the prebiotic potential and that their intake may improve dysbiosis or maintain the gastrointestinal health through a balanced intestinal microbiota, although additional studies are necessary.

  7. Xylo-Oligosaccharides and Inulin Affect Genotoxicity and Bacterial Populations Differently in a Human Colonic Simulator Challenged with Soy Protein

    Directory of Open Access Journals (Sweden)

    Michael A. Conlon

    2013-09-01

    Full Text Available High dietary intakes of some protein sources, including soy protein, can increase colonic DNA damage in animals, whereas some carbohydrates attenuate this. We investigated whether inulin and xylo-oligosaccharides (XOS could be protective against DNA strand breaks by adding them to a human colonic simulator consisting of a proximal vessel (PV (pH 5.5 and a distal vessel (DV (pH 6.8 inoculated with human faeces and media containing soy protein. Genotoxicity of the liquid phase and microbial population changes in the vessels were measured. Soy protein (3% was fermented with 1% low amylose cornstarch for 10 day followed by soy protein with 1% XOS or 1% inulin for 10 day. Inulin did not alter genotoxicity but XOS significantly reduced PV genotoxicity and increased DV genotoxicity. Inulin and XOS significantly increased butyrate concentration in the DV but not PV. Numbers of the key butyrate-producing bacterium Faecalibacterium prausnitzii were significantly increased in the PV and DV by inulin but significantly decreased by XOS in both vessels. Other bacteria examined were also significantly impacted by the carbohydrate treatments or by the vessel (i.e., pH. There was a significant overall inverse correlation between levels of damage induced by the ferments and levels of sulphate-reducing bacteria, Bacteroides fragilis, and acetate. In conclusion, dietary XOS can potentially modulate the genotoxicity of the colonic environment and specific bacterial groups and short chain fatty acids may mediate this.

  8. Metabolic engineering of Escherichia coli to produce 2'-fucosyllactose via salvage pathway of guanosine 5'-diphosphate (GDP)-l-fucose.

    Science.gov (United States)

    Chin, Young-Wook; Seo, Nari; Kim, Jae-Han; Seo, Jin-Ho

    2016-11-01

    2'-Fucosyllactose (2-FL) is one of the key oligosaccharides in human milk. In the present study, the salvage guanosine 5'-diphosphate (GDP)-l-fucose biosynthetic pathway from fucose was employed in engineered Escherichia coli BL21star(DE3) for efficient production of 2-FL. Introduction of the fkp gene coding for fucokinase/GDP-l-fucose pyrophosphorylase (Fkp) from Bacteroides fragilis and the fucT2 gene encoding α-1,2-fucosyltransferase from Helicobacter pylori allows the engineered E. coli to produce 2-FL from fucose, lactose and glycerol. To enhance the lactose flux to 2-FL production, the attenuated, and deleted mutants of β-galactosidase were employed. Moreover, the 2-FL yield and productivity were further improved by deletion of the fucI-fucK gene cluster coding for fucose isomerase (FucI) and fuculose kinase (FucK). Finally, fed-batch fermentation of engineered E. coli BL21star(DE3) deleting lacZ and fucI-fucK, and expressing fkp and fucT2 resulted in 23.1 g/L of extracellular concentration of 2-FL and 0.39 g/L/h productivity. Biotechnol. Bioeng. 2016;113: 2443-2452. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

  9. Enhancing flora balance in the gastrointestinal tract of mice by lactic acid bacteria from Chinese sourdough and enzyme activities indicative of metabolism of protein, fat, and carbohydrate by the flora.

    Science.gov (United States)

    Yang, Dong; Yu, Xiaomin; Wu, Yaoping; Chen, Xingxing; Wei, Hua; Shah, Nagendra P; Xu, Feng

    2016-10-01

    In this study, we investigated the effect of administration of 5 strains of lactic acid bacteria (LAB) isolated from traditional Chinese sourdough on the flora balance of gastrointestinal tract of mice. We specifically measured Enterococcus, Enterobacter, Bacteroides, and Lactobacillus by plate count and real-time PCR methods, and α-glucosidase, lactate dehydrogenase, esterase, and aminopeptidase activities as indicative of metabolism of sugar, fat, and protein from LAB isolated from feces of mice in vitro. The results showed that administration of Lactobacillus acidophilus LAC0201 and Lactobacillus fermentum LFE0302 lowered the uricacid index of serum. Lactobacillus acidophilus LAC0201, L. fermentum LFE0302, as well as Lactobacillus curvatus LCU0401 administration resulted in a reduction in the opportunistic pathogens (i.e., Enterococcus and Enterobacter), meanwhile, administration of L. fermentum LFE0302 and Lactobacillus sp. ULA0104 resulted in an increase in the counts of Lactobacillus. Lactobacillus fermentum LFE0302 administration increased starch digestion of intestinal flora after 4wk of feeding and also resulted in increased α-glucosidase activity in the intestinal flora after 3wk of feeding. We found a similar trend in esterase activity after administration of L. acidophilus LAC0201 for 3wk. Hence, our study suggested that LAB from Chinese sourdough might be used as potential probiotics to strengthen the flora balance in gastrointestinal tract and positively change the metabolism of nutrients through bacterial enzyme activities. Copyright © 2016 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

  10. HLA-B27 and human β2-microglobulin affect the gut microbiota of transgenic rats.

    Directory of Open Access Journals (Sweden)

    Phoebe Lin

    Full Text Available The HLA-B27 gene is a major risk factor for clinical diseases including ankylosing spondylitis, acute anterior uveitis, reactive arthritis, and psoriatic arthritis, but its mechanism of risk enhancement is not completely understood. The gut microbiome has recently been shown to influence several HLA-linked diseases. However, the role of HLA-B27 in shaping the gut microbiome has not been previously investigated. In this study, we characterize the differences in the gut microbiota mediated by the presence of the HLA-B27 gene. We identified differences in the cecal microbiota of Lewis rats transgenic for HLA-B27 and human β2-microglobulin (hβ2m, compared with wild-type Lewis rats, using biome representational in situ karyotyping (BRISK and 16S rRNA gene sequencing. 16S sequencing revealed significant differences between transgenic animals and wild type animals by principal coordinates analysis. Further analysis of the data set revealed an increase in Prevotella spp. and a decrease in Rikenellaceae relative abundance in the transgenic animals compared to the wild type animals. By BRISK analysis, species-specific differences included an increase in Bacteroides vulgatus abundance in HLA-B27/hβ2m and hβ2m compared to wild type rats. The finding that HLA-B27 is associated with altered cecal microbiota has not been shown before and can potentially provide a better understanding of the clinical diseases associated with this gene.

  11. Changes in Composition and Function of Human Intestinal Microbiota Exposed to Chlorpyrifos in Oil as Assessed by the SHIME® Model

    Directory of Open Access Journals (Sweden)

    Julie Reygner

    2016-11-01

    Full Text Available The presence of pesticide residues in food is a public health problem. Exposure to these substances in daily life could have serious effects on the intestine—the first organ to come into contact with food contaminants. The present study investigated the impact of a low dose (1 mg/day in oil of the pesticide chlorpyrifos (CPF on the community structure, diversity and metabolic response of the human gut microbiota using the SHIME® model (six reactors, representing the different parts of the gastrointestinal tract. The last three reactors (representing the colon were inoculated with a mixture of feces from human adults. Three time points were studied: immediately before the first dose of CPF, and then after 15 and 30 days of CPF-oil administration. By using conventional bacterial culture and molecular biology methods, we showed that CPF in oil can affect the gut microbiota. It had the greatest effects on counts of culturable bacteria (with an increase in Enterobacteria, Bacteroides spp. and clostridia counts, and a decrease in bifidobacterial counts and fermentative activity, which were colon-segment-dependent. Our results suggest that: (i CPF in oil treatment affects the gut microbiota (although there was some discordance between the culture-dependent and culture-independent analyses; (ii the changes are “SHIME®-compartment” specific; and (iii the changes are associated with minor alterations in the production of short-chain fatty acids and lactate.

  12. Bacterial polysaccharide levan as stabilizing, non-toxic and functional coating material for microelement-nanoparticles.

    Science.gov (United States)

    Bondarenko, Olesja M; Ivask, Angela; Kahru, Anne; Vija, Heiki; Titma, Tiina; Visnapuu, Meeri; Joost, Urmas; Pudova, Ksenia; Adamberg, Signe; Visnapuu, Triinu; Alamäe, Tiina

    2016-01-20

    Levan, fructose-composed biopolymer of bacterial origin, has potential in biotechnology due to its prebiotic and immunostimulatory properties. In this study levan synthesized by levansucrase from Pseudomonas syringae was thoroughly characterized and used as multifunctional biocompatible coating material for microelement-nanoparticles (NPs) of selenium, iron and cobalt. Transmission electron microscopy (TEM), hydrodynamic size measurements (DLS) and X-ray photoelectron spectroscopy (XPS) showed the interaction of levan with NPs. Levan stabilized the dispersions of NPs, decreased their toxicity and had protective effect on human intestinal cells Caco-2. In addition, levan attached to cobalt NPs remained accessible as a substrate for the colon bacteria Bacteroides thetaiotaomicron. We suggest that the combination of levan and nutritionally important microelements in the form of NPs serves as a first step towards a novel "2 in 1" approach for food supplements to provide safe and efficient delivery of microelements for humans and support beneficial gut microbiota with nutritional oligosaccharides. Copyright © 2015 Elsevier Ltd. All rights reserved.

  13. Fluorescence in situ hybridization analysis of hindgut bacteria associated with the development of equine laminitis.

    Science.gov (United States)

    Milinovich, Gabriel J; Trott, Darren J; Burrell, Paul C; Croser, Emma L; Al Jassim, Rafat A M; Morton, John M; van Eps, Andrew W; Pollitt, Christopher C

    2007-08-01

    Carbohydrate-induced laminitis in horses is characterized by marked changes in the composition of the hindgut microbiota, from a predominantly Gram-negative population to one dominated by Gram-positive bacteria. The objective of this study was to monitor changes in the relative abundance of selected hindgut bacteria that have previously been implicated in the pathophysiology of equine laminitis using fluorescence in situ hybridization (FISH). Caecal cannulae were surgically implanted in five Standardbred horses and laminitis induced by oral administration of a bolus dose of oligofructose. Caecal fluid and faecal specimens were collected over a 48 h period at 2 to 4 h intervals post-oligofructose administration and subjected to FISH using probes specific for nine bacterial groups to determine changes in their relative abundance compared with total bacteria hybridizing to the generic EUBMIX probe. Additionally, hoof biopsies were taken over the course of the experiment at 6 h intervals and evaluated for histopathological changes consistent with laminitis, allowing changes in hindgut microbiota to be correlated with the onset of lesions in the foot. Of the microorganisms specifically targeted, streptococci of the Streptococcus bovis/equinus complex were the only bacteria that consistently proliferated in both caecal fluid and faeces immediately before the onset of histological signs of laminitis. Furthermore, lactobacilli, Enterobacteriaceae, Allisonella histaminiformans, enterococci, Bacteroides fragilis, Mitsuokella jalaludinii and Clostridium difficile did not establish significant populations in the hindgut before the onset of equine laminitis.

  14. Human colorectal mucosal microbiota correlates with its host niche physiology revealed by endomicroscopy.

    Science.gov (United States)

    Wang, Ai-Hua; Li, Ming; Li, Chang-Qing; Kou, Guan-Jun; Zuo, Xiu-Li; Li, Yan-Qing

    2016-02-26

    The human gut microbiota plays a pivotal role in the maintenance of health, but how the microbiota interacts with the host at the colorectal mucosa is poorly understood. We proposed that confocal laser endomicroscopy (CLE) might help to untangle this relationship by providing in vivo physiological information of the mucosa. We used CLE to evaluate the in vivo physiology of human colorectal mucosa, and the mucosal microbiota was quantified using 16 s rDNA pyrosequencing. The human mucosal microbiota agglomerated to three major clusters dominated by Prevotella, Bacteroides and Lactococcus. The mucosal microbiota clusters did not significantly correlate with the disease status or biopsy sites but closely correlated with the mucosal niche physiology, which was non-invasively revealed by CLE. Inflammation tilted two subnetworks within the mucosal microbiota. Infiltration of inflammatory cells significantly correlated with multiple components in the predicted metagenome, such as the VirD2 component of the type IV secretory pathway. Our data suggest that a close correlation exists between the mucosal microbiota and the colorectal mucosal physiology, and CLE is a clinically available tool that can be used to facilitate the study of the in vivo correlation between colorectal mucosal physiology and the mucosal microbiota.

  15. Changes in the composition of intestinal fungi and their role in mice with dextran sulfate sodium-induced colitis.

    Science.gov (United States)

    Qiu, Xinyun; Zhang, Feng; Yang, Xi; Wu, Na; Jiang, Weiwei; Li, Xia; Li, Xiaoxue; Liu, Yulan

    2015-05-27

    Intestinal fungi are increasingly believed to greatly influence gut health. However, the effects of fungi on intestinal inflammation and on gut bacterial constitution are not clear. Here, based on pyrosequencing method, we reveal that fungal compositions vary in different intestinal segments (ileum, cecum, and colon), prefer different colonization locations (mucosa and feces), and are remarkably changed during intestinal inflammation in dextran sulfate sodium (DSS)-colitis mouse models compare to normal controls: Penicillium, Wickerhamomyces, Alternaria, and Candida are increased while Cryptococcus, Phialemonium, Wallemia and an unidentified Saccharomycetales genus are decreased in the guts of DSS-colitis mice. Fungi-depleted mice exhibited aggravated acute DSS-colitis associated with gain of Hallella, Barnesiella, Bacteroides, Alistipes, and Lactobacillus and loss of butyrate-producing Clostridium XIVa, and Anaerostipes compare with normal control. In contrast, bacteria-depleted mice show attenuated acute DSS-colitis. Mice with severely chronic recurrent DSS-colitis show increased plasma (1,3)-β-D-glucan level and fungal translocation into the colonic mucosa, mesenteric lymph nodes and spleen. This work demonstrate the different roles of fungi in acute and chronic recurrent colitis: They are important counterbalance to bacteria in maintaining intestinal micro-ecological homeostasis and health in acutely inflamed intestines, but can harmfully translocate into abnormal sites and could aggravate disease severity in chronic recurrent colitis.

  16. Spontaneous perforation of pyometra: a report of seven cases and review of the literature.

    Science.gov (United States)

    Ikeda, Michi; Takahashi, Toshifumi; Kurachi, Hirohisa

    2013-01-01

    The spontaneous perforation of pyometra is very rare and is associated with a poor prognosis. The present study aimed to evaluate the clinical characteristics and prognostic factors for patient survival. We reported on 7 patients with spontaneous rupture of pyometra. We also reviewed 47 additional published cases. Thus, all 54 patients were analyzed for mortality. We investigated the prognosis in 44 of 54 patients, excluding 8 patients with undocumented outcome and 2 who died of other diseases. The mortality rate was 25% (11 of 44). In univariate analysis, variables such as age, correct preoperative diagnosis, comorbidities, the presence of malignancy, and hysterectomy were not significant between surviving and deceased patients. In bacterial cultures from the peritoneal cavity, the most common etiological organisms were Escherichia coli and anaerobes such as Bacteroides and Peptococcus species. The rate of isolation of anaerobic bacteria was significantly increased in patients who died (odds ratio, 6.33; 95% confidence interval, 1.28-31.02; p = 0.04). Antibiotic therapy for E. coli and anaerobes should be considered in patients with spontaneous perforation of pyometra. Copyright © 2013 S. Karger AG, Basel.

  17. Nano-hydroxyapatite alleviates the detrimental effects of heavy metals on plant growth and soil microbes in e-waste-contaminated soil.

    Science.gov (United States)

    Wei, Liu; Wang, Shutao; Zuo, Qingqing; Liang, Shuxuan; Shen, Shigang; Zhao, Chunxia

    2016-06-15

    The crude recycling activities of e-waste have led to the severe and complex contamination of e-waste workshop topsoil (0-10 cm) by heavy metals. After nano-hydroxyapatite (NHAp) application in June 2013, plant and soil samples were obtained in November 2013, December 2013, March 2014 and June 2014. The results showed that NHAp effectively reduced the concentration of CaCl2-extractable Pb, Cu, Cd, and Zn in the topsoil and significantly reduced the metal content in ryegrass and also increased the plant biomass compared with that of the control. Moreover, the concentrations of CaCl2-extractable metals in the soil decreased with increasing NHAp. NHAp application also increased the activities of soil urease, phosphatase and dehydrogenase. Moreover, the soil bacterial diversity and community structure were also altered after NHAp application. Particularly, Stenotrophomonas sp. and Bacteroides percentages were increased. Our work proves that NHAp application can alleviate the detrimental effects of heavy metals on plants grown in e-waste-contaminated soil and soil enzyme activities, as well as soil microbial diversity.

  18. Understanding the degradation of Congo red and bacterial diversity in an air-cathode microbial fuel cell being evaluated for simultaneous azo dye removal from wastewater and bioelectricity generation.

    Science.gov (United States)

    Sun, Jian; Li, Youming; Hu, Yongyou; Hou, Bin; Zhang, Yaping; Li, Sizhe

    2013-04-01

    We investigated the mechanism of Congo red degradation and bacterial diversity in a single-chambered microbial fuel cell (MFC) incorporating a microfiltration membrane and air-cathode. The MFC was operated continuously for more than 4 months using a mixture of Congo red and glucose as fuel. We demonstrated that the Congo red azo bonds were reduced at the anode to form aromatic amines. This is consistent with the known mechanism of anaerobic biodegradation of azo dyes. The MFC developed a less dense biofilm at the anode in the presence of Congo red compared to its absence indicating that Congo red degradation negatively affected biofilm formation. Denaturing gradient gel electrophoresis and direct 16S ribosomal DNA gene nucleotide sequencing revealed that the microbial communities differed depending on whether Congo red was present in the MFC. Geobacter-like species known to generate electricity were detected in the presence or absence of Congo red. In contrast, Azospirillum, Methylobacterium, Rhodobacter, Desulfovibrio, Trichococcus, and Bacteroides species were only detected in its presence. These species were most likely responsible for degrading Congo red.

  19. Enrichment of extremophilic exoelectrogens in microbial electrolysis cells using Red Sea brine pools as inocula

    KAUST Repository

    Chehab, Noura A.

    2017-05-03

    Applying microbial electrochemical technologies for the treatment of highly saline or thermophilic solutions is challenging due to the lack of proper inocula to enrich for efficient exoelectrogens. Brine pools from three different locations (Valdivia, Atlantis II and Kebrit) in the Red Sea were investigated as potential inocula sources for enriching exoelectrogens in microbial electrolysis cells (MECs) under thermophilic (70°C) and hypersaline (25% salinity) conditions. Of these, only the Valdivia brine pool produced high and consistent current 6.8 ± 2.1 A/m2-anode in MECs operated at a set anode potential of +0.2 V vs. Ag/AgCl (+0.405 V vs. standard hydrogen electrode). These results show that exoelectrogens are present in these extreme environments and can be used to startup MEC under thermophilic and hypersaline conditions. Bacteroides was enriched on the anode of the Valdivia MEC, but it was not detected in the open circuit voltage reactor seeded with the Valdivia brine pool.

  20. More than meets the eye: associations of vaginal bacteria with gram stain morphotypes using molecular phylogenetic analysis.

    Science.gov (United States)

    Srinivasan, Sujatha; Morgan, Martin T; Liu, Congzhou; Matsen, Frederick A; Hoffman, Noah G; Fiedler, Tina L; Agnew, Kathy J; Marrazzo, Jeanne M; Fredricks, David N

    2013-01-01

    Bacterial vaginosis (BV) is a highly prevalent condition associated with adverse health outcomes. Gram stain analysis of vaginal fluid is the standard for confirming the diagnosis of BV, wherein abundances of key bacterial morphotypes are assessed. These Lactobacillus, Gardnerella, Bacteroides, and Mobiluncus morphotypes were originally linked to particular bacterial species through cultivation studies, but no studies have systematically investigated associations between uncultivated bacteria detected by molecular methods and Gram stain findings. In this study, 16S-rRNA PCR/pyrosequencing was used to examine associations between vaginal bacteria and bacterial morphotypes in 220 women with and without BV. Species-specific quantitative PCR (qPCR) and fluorescence in Situ hybridization (FISH) methods were used to document concentrations of two bacteria with curved rod morphologies: Mobiluncus and the fastidious BV-associated bacterium-1 (BVAB1). Rank abundance of vaginal bacteria in samples with evidence of curved gram-negative rods showed that BVAB1 was dominant (26.1%), while Mobiluncus was rare (0.2% of sequence reads). BVAB1 sequence reads were associated with Mobiluncus morphotypes (pGram-negative rods designated Mobiluncus morphotypes on Gram stain are more likely BVAB1. These findings provide a clearer picture of the bacteria associated with morphotypes on vaginal Gram stain.

  1. Response of goose intestinal microflora to the source and level of dietary fiber.

    Science.gov (United States)

    Zhou, Haizhu; Guo, Wei; Zhang, Tao; Xu, Bo; Zhang, Di; Teng, Zhanwei; Tao, Dapeng; Lou, Yujie; Gao, Yunhang

    2018-02-14

    Geese are capable of digesting and making use of a high-fiber diet, but the mechanism is not well understood and would be of great significance for the development and utilization of roughage resources. In this study, we investigated the effect of dietary fiber (source: corn stover and alfalfa, included at 5% or 8%) on microflora in goose intestines. We used 35-day-old Carlos geese in which we first studied the influence of fiber ingestion on diet digestibility and immune organ indices of geese and found that high dietary fiber (8% content) significantly increased feed intake, the digestibility of neutral and acid detergent fiber, and thymus, bursa, and spleen size. Subsequently, we investigated the effect of dietary fiber on the microbial flora in the various intestinal segments by high throughput sequencing. The bacterial diversity and relative abundance were significantly affected by the type and amount of dietary fiber fed, including that of cellulolytic bacteria such as Bacteroides, Ruminococcus, Clostridium, and Pseudomonas spp. Finally, we isolated and identified 8 strains with cellulolytic ability from goose intestine and then analyzed their activities in combination. The optimal combination for cellulase activity was Cerea bacillus and Pseudomonas aeruginosa. This study has laid a theoretical and practical foundation for knowledge of the efficient conversion and utilization of cellulose by geese. © 2018 Poultry Science Association Inc.

  2. Microbial community structure in moraine lakes and glacial meltwaters, Mount Everest.

    Science.gov (United States)

    Liu, Yongqin; Yao, Tandong; Jiao, Nianzhi; Kang, Shichang; Zeng, Yonghui; Huang, Sijun

    2006-12-01

    The bacterial diversity and abundance in two moraine lakes and two glacial meltwaters (5140, 5152, 5800 and 6350 m above sea level, respectively) in the remote Mount Everest region were examined through 16S rRNA gene clone library and flow cytometry approaches. In total, 247 clones were screened by RFLP and 60 16S rRNA gene sequences were obtained, belonging to the following groups: Proteobacteria (8% alpha subdivision, 21% beta subdivision, and 1% gamma subdivision), Cytophaga-Flavobacteria-Bacteroides (CFB) (54%), Actinobacteria (4%), Planctomycetes (2%), Verrucomicrobia (2%), Fibrobacteres (1%) and Eukaryotic chroloplast (3%), respectively. The high dominance of CFB distinguished the Mount Everest waters from other mountain lakes. The highest bacterial abundance and diversity occurred in the open moraine lake at 5152 m, and the lowest in the glacial meltwater at 6350 m. Low temperature at high altitude is considered to be critical for component dominancy. At the same altitude, nutrient availability plays a role in regulating population structure. Our results also show that the bacteria in Mount Everest may be derived from different sources.

  3. Changes in cecal microbiota and mucosal gene expression revealed new aspects of epizootic rabbit enteropathy.

    Directory of Open Access Journals (Sweden)

    Christine Bäuerl

    Full Text Available Epizootic Rabbit Enteropathy (ERE is a severe disease of unknown aetiology that mainly affects post-weaning animals. Its incidence can be prevented by antibiotic treatment suggesting that bacterial elements are crucial for the development of the disease. Microbial dynamics and host responses during the disease were studied. Cecal microbiota was characterized in three rabbit groups (ERE-affected, healthy and healthy pretreated with antibiotics, followed by transcriptional analysis of cytokines and mucins in the cecal mucosa and vermix by q-rtPCR. In healthy animals, cecal microbiota with or without antibiotic pretreatment was very similar and dominated by Alistipes and Ruminococcus. Proportions of both genera decreased in ERE rabbits whereas Bacteroides, Akkermansia and Rikenella increased, as well as Clostridium, γ-Proteobacteria and other opportunistic and pathogenic species. The ERE group displayed remarkable dysbiosis and reduced taxonomic diversity. Transcription rate of mucins and inflammatory cytokines was very high in ERE rabbits, except IL-2, and its analysis revealed the existence of two clearly different gene expression patterns corresponding to Inflammatory and (mucin Secretory Profiles. Furthermore, these profiles were associated to different bacterial species, suggesting that they may correspond to different stages of the disease. Other data obtained in this work reinforced the notion that ERE morbidity and mortality is possibly caused by an overgrowth of different pathogens in the gut of animals whose immune defence mechanisms seem not to be adequately responding.

  4. A primary assessment of the endophytic bacterial community in a xerophilous moss (Grimmia montana using molecular method and cultivated isolates

    Directory of Open Access Journals (Sweden)

    Xiao Lei Liu

    2014-01-01

    Full Text Available Investigating the endophytic bacterial community in special moss species is fundamental to understanding the microbial-plant interactions and discovering the bacteria with stresses tolerance. Thus, the community structure of endophytic bacteria in the xerophilous moss Grimmia montana were estimated using a 16S rDNA library and traditional cultivation methods. In total, 212 sequences derived from the 16S rDNA library were used to assess the bacterial diversity. Sequence alignment showed that the endophytes were assigned to 54 genera in 4 phyla (Proteobacteria, Firmicutes, Actinobacteria and Cytophaga/Flexibacter/Bacteroids. Of them, the dominant phyla were Proteobacteria (45.9% and Firmicutes (27.6%, the most abundant genera included Acinetobacter, Aeromonas, Enterobacter, Leclercia, Microvirga, Pseudomonas, Rhizobium, Planococcus, Paenisporosarcina and Planomicrobium. In addition, a total of 14 species belonging to 8 genera in 3 phyla (Proteobacteria, Firmicutes, Actinobacteria were isolated, Curtobacterium, Massilia, Pseudomonas and Sphingomonas were the dominant genera. Although some of the genera isolated were inconsistent with those detected by molecular method, both of two methods proved that many different endophytic bacteria coexist in G. montana. According to the potential functional analyses of these bacteria, some species are known to have possible beneficial effects on hosts, but whether this is the case in G. montana needs to be confirmed.

  5. Temporal distribution of bacterial community structure in the Changjiang Estuary hypoxia area and the adjacent East China Sea

    International Nuclear Information System (INIS)

    Liu Min; Huang Huiqin; Bao Shixiang; Xiao Tian; Zhang Wuchang; Wu Ying; Zhou Feng

    2012-01-01

    Bacterial community structure and the effects of environmental factors on the microbial community distribution were investigated in the Changjiang Estuary hypoxia area and its adjacent area in the East China Sea (ECS) in June, August and October, 2006. Profiles of bacterial communities were generated by denaturing gradient gel electrophoresis (DGGE) of 16S rRNA genes followed by DNA sequence analysis. The dominant bacterial groups were affiliated to Gammaproteobacteria, Cytophaga–Flavobacteria–Bacteroides (CFB), Deltaproteobacteria, Cyanobacteria and Firmicutes, which were mostly from the marine seawater ecosystem. Effects of environmental factors on the bacterial community distribution were analyzed by the ordination technique of canonical correspondence analysis (CCA). The environmental factors significantly influencing bacterial community structure were different in the three months; dissolved organic carbon (DOC) and temperature in June and nitrite in August. No environmental variables displayed significant influence on the bacterial community at the 5% level in October. The seasonal environmental heterogeneity in the Changjiang Estuary and the adjacent ECS, such as seasonal hydrodynamic conditions and riverine input of nutrients, might be the reason for the difference in the key environmental factors determining the bacterial community in the three months. (letter)

  6. Investigation of Chitosan for Prevention of Diabetic Progression Through Gut Microbiota Alteration in Sugar Rich Diet Induced Diabetic Rats.

    Science.gov (United States)

    Prajapati, Bhumika; Rajput, Parth; Jena, Prasant Kumar; Seshadri, Sriram

    2015-01-01

    Sugar rich diet induces inflammation and insulin resistance mainly through gut microbiota alteration. Gut microflora dysbiosis increases plasma lipopolysaccharide and reduces short chain fatty acids to impair the insulin signaling cascades by different molecular pathways to progress into diabetes. Chitosan based formulations have major significance in insulin delivery system due to their ability to protect the insulin from enzymatic degradation and its efficient inter-epithelial transport. This study was designed to investigate the effect of chitosan administration on gut microflora mediated signaling pathways to prevent the diet induced diabetes. Male wistar rats were divided into non-diabetic group with a normal diet (CD), diabetic group with high sucrose diet (HSD) and treatment group with HSD and chitosan (60 mg/kg). After 8 weeks of the study, significant alterations in two major gut dominant microbial phyla i.e Firmicutes and Bacteroides and four dominant microbial species i.e. Lactobacilli, Bifidobacteria, Escherichia and Clostridia were observed in HSD group compared to CD. This microbial dysbiosis in dominant phyla was significantly prevented in chitosan administrated HSD group. Chitosan administration had also reduced the HSD induced activation of Toll like receptors and Nod like receptors signaling pathways compared to HSD control group to reduce the inflammation. These suggest that chitosan can prevent the progression of Type 2 Diabetes through gut microbiota alteration, reducing endotoxin and microbes mediated inflammation.

  7. Gut microbiota-involved mechanisms in enhancing systemic exposure of ginsenosides by coexisting polysaccharides in ginseng decoction

    Science.gov (United States)

    Zhou, Shan-Shan; Xu, Jun; Zhu, He; Wu, Jie; Xu, Jin-Di; Yan, Ru; Li, Xiu-Yang; Liu, Huan-Huan; Duan, Su-Min; Wang, Zhuo; Chen, Hu-Biao; Shen, Hong; Li, Song-Lin

    2016-03-01

    Oral decoctions of traditional Chinese medicines (TCMs) serve for therapeutic and prophylactic management of diseases for centuries. Small molecules and polysaccharides are the dominant chemicals co-occurred in the TCM decoction. Small molecules are well-studied by multidisciplinary elaborations, whereas the role of polysaccharides remains largely elusive. Here we explore a gut microbiota-involved mechanism by which TCM polysaccharides restore the homeostasis of gut microbiota and consequently promote the systemic exposure of concomitant small molecules in the decoction. As a case study, ginseng polysaccharides and ginsenosides in Du-Shen-Tang, the decoction of ginseng, were investigated on an over-fatigue and acute cold stress model. The results indicated that ginseng polysaccharides improved intestinal metabolism and absorption of certain ginsenosides, meanwhile reinstated the perturbed holistic gut microbiota, and particularly enhanced the growth of Lactobacillus spp. and Bacteroides spp., two major metabolic bacteria of ginsenosides. By exploring the synergistic actions of polysaccharides with small molecules, these findings shed new light on scientization and rationalization of the classic TCM decoctions in human health care.

  8. Effect of periodontal status of rotary electric toothbrushes vs. manual toothbrushes during periodontal maintenance. II. Microbiological results.

    Science.gov (United States)

    Murray, P A; Boyd, R L; Robertson, P B

    1989-07-01

    We compared the use of a rotary electric toothbrush with conventional toothbrushing for their effectiveness in modulating the subgingival microbiota. Forty subjects who had received periodontal treatment for moderate to advanced periodontitis and were on 3-month periodontal maintenance were divided into two equal groups matched for age and sex. One group used only the rotary tooth cleaner and the other group used conventional toothbrushing, dental floss, and toothpicks for 12 months. Subgingival plaque samples (two sites per patient) were taken from 10 subjects per group at baseline, 6 months, and 12 months and analyzed for percentage of obligate anaerobes and colony-forming units of black-pigmented Bacteroides, Fusobacterium, Actinomyces, Streptococcus, and Veillonella spp. The percentage of spirochetes and motile rods was determined by darkfield microscopy. Results showed that levels of obligate anaerobes, Fusobacterium, and Actinomyces and percentage of spirochetes and motile rods decreased significantly (P less than 0.05), while levels of Streptococcus spp. increased (P less than 0.05) for both groups. However, there was no significant difference between the two groups, indicating that the rotary tooth cleaner and conventional toothbrushing are equally effective in controlling gingivitis and fostering a less pathogenic microflora.

  9. Vaginal microbiota in menopause

    Directory of Open Access Journals (Sweden)

    Martinus Tarina

    2016-12-01

    Full Text Available The human vagina together with its resident, microbiota, comprise a dynamic ecosystem. Normal microbiota is dominated by Lactobacillus species, and pathogen microbiota such as Gardnerella species and Bacteroides species can occur due to decrease in Lactobacillus domination. Lactobacillus plays an essential role in keeping normal vaginal microbiota in balance. Vaginal microbiota adapts to pH change and hormonal value. Changes in the vaginal microbiota over a woman’s lifespan will influence the colonization of pathogenic microbes. They include changes in child, puberty, reproductive state, menopause, and postmenopause. Estrogen levels change will affect the colonization of pathogenic microbium, leading to genitourinary syndrome of menopause. Vulvovaginal atrophy is often found in postmenopausal women, and dominated by L. iners, Anaerococcus sp, Peptoniphilus sp, Prevotella sp, and Streptococcus sp. The normal vaginal microbiota’s imbalance in menopause will cause diseases such as bacterial vaginosis, and recurrent vulvovaginal candidiasis due to hormonal therapies. Changes in the vaginal microbiota due to bacterial vaginosis are characterized by decrease in H2O2-producing Lactobacillus. They are also caused by the increase in numbers and concentration of Gardnerella vaginalis, Mycoplasma hominis, and other anaerob species such as Peptostreptococci, Prevotella spp, and Mobiluncus spp.

  10. Assessment of bacterial diversity in Hyalomma aegyptium, H. marginatum and H. excavatum ticks through tag-encoded pyrosequencing.

    Science.gov (United States)

    Keskin, Adem; Bursali, Ahmet; Snow, David E; Dowd, Scot E; Tekin, Saban

    2017-12-01

    Ticks are among the most significant human-biting ectoparasites and they play a major role in transmission of many pathogenic agents to humans. In the present study, three species of Hyalomma ticks, Hyalomma aegyptium, H. marginatum and H. excavatum, were examined for the presence of zoonotic bacteria, both male and female ticks alike. Examination of microbial diversity with tag-encoded pyrosequencing indicates that H. marginatum and H. excavatum were more diversity rich than H. aegyptium. Although numerous pathogenic and non-pathogenic bacterial genera were detected, including Acidovorax, Bacillus, Bacteroides, Bdellovibrio, Clostridium, Curvibacter, Escherichia, Flavobacterium, Limnohabitans, Paenibacillus, Ralstonia, Sarcina, Sediminibacterium, Segetibacter Stenotrophomonas and Variovorax, the predominant zoonotic bacteria represented in these ticks were genera Borrelia, Francisella, and Rickettsia. To the authors' knowledge, this work represents the first detection of Yersinia enterocolitica in the tick H. excavatum, raising questions regarding the vector competency of this tick, as well as associations of different disease representations perhaps through previously unforeseen routes of pathogen introduction. Likewise, similar questions are related to the presence of Legionella pneumophila in one H. excavatum sample.

  11. [Role of several periodontopathogenic microorganisms and tlr4 gene Asp299Gly polymorphism in atherosclerosis pathogenesis].

    Science.gov (United States)

    Skochko, O V; Bobrova, N A; Izmaylova, O V; Kaĭdashev, I P

    2011-01-01

    Establishment of presence of periodonto-pathogenic microorganisms in atherosclerosis plaque and surrounding tissues, and possible relation of development of atherosclerosis and TLR4 gene Asp299Gly polymorphism in ischemic heart disease patients (IHD). Samples of coronary vessels obtained during autopsy of 31 individuals deceased from IHD and 5 individuals deceased due to reasons not related with IHD were studied. PCR was used to determine DNA of the microorganisms. TLR4 gene polymorphic segment was amplified by using specific primers. Analysis of coronary vessel atherosclerotic plaques revealed presence of the studied periodontopathogenic microorganisms in 83.9% of cases. The most frequently detected were Porphyromonas gingivalis (64.5%), Treponema denticola (41.9%), Actinobacillus actinomycetemcomitans (32.3%), less frequently--Bacteroides forsythus and Prevotella intermedia (12.9% and 6.5% respectively). In 51.6% of cases 2 or more microorganisms were detected. Only in 11.1% ofcoronary artery samples, with plaques containing microorganisms, the microorganisms were detected in undamaged tissues. Patients deceased from IHD had TLR4 gene 299Gly allele significantly more frequently. The studied periodontopathogenic microorganisms can play an important role in the pathogenesis of atherosclerotic injury of coronary arteries in IHD. The presence of TLR4 gene allele 299Gly significantly contributes to these processes.

  12. Determination of free and bound riboflavin in cow's milk using a novel flavin-binding protein.

    Science.gov (United States)

    Koop, Julia; Monschein, Stefanie; Pauline Macheroux, E; Knaus, Tanja; Macheroux, Peter

    2014-03-01

    A recently described putative protease from the gut bacterium Bacteroides thetaiotaomicron (termed ppBat) exhibits two tryptophan residues in the interface which enable specific binding of the isoalloxazine heterocycle of riboflavin and its two cofactor forms, FMN and FAD. Recombinant ppBat was used to capture riboflavin from bovine milk directly without any prior preparation steps. The flavin-loaded protein was then re-isolated by means of affinity chromatography to identify and quantify the captured flavins. Free riboflavin concentrations were determined to 197 and 151μg/l for milk with 3.5% and 0.5% fat content, respectively. Total riboflavin concentrations were also determined after acid-treatment of milk and were 4-5 times higher than for free riboflavin. Free FMN and FAD were not detectable and only trace amounts of FMN were found in milk following acid treatment. The method appears to be amenable to develop a direct assay for free riboflavin in milk and other foods. Copyright © 2013 Elsevier Ltd. All rights reserved.

  13. Non Digestible Oligosaccharides Modulate the Gut Microbiota to Control the Development of Leukemia and Associated Cachexia in Mice.

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    Laure B Bindels

    Full Text Available We tested the hypothesis that changing the gut microbiota using pectic oligosaccharides (POS or inulin (INU differently modulates the progression of leukemia and related metabolic disorders. Mice were transplanted with Bcr-Abl-transfected proB lymphocytes mimicking leukemia and received either POS or INU in their diet (5% for 2 weeks. Combination of pyrosequencing, PCR-DGGE and qPCR analyses of the 16S rRNA gene revealed that POS decreased microbial diversity and richness of caecal microbiota whereas it increased Bifidobacterium spp., Roseburia spp. and Bacteroides spp. (affecting specifically B. dorei to a higher extent than INU. INU supplementation increased the portal SCFA propionate and butyrate, and decreased cancer cell invasion in the liver. POS treatment did not affect hepatic cancer cell invasion, but was more efficient than INU to decrease the metabolic alterations. Indeed, POS better than INU delayed anorexia linked to cancer progression. In addition, POS treatment increased acetate in the caecal content, changed the fatty acid profile inside adipose tissue and counteracted the induction of markers controlling β-oxidation, thereby hampering fat mass loss. Non digestible carbohydrates with prebiotic properties may constitute a new nutritional strategy to modulate gut microbiota with positive consequences on cancer progression and associated cachexia.

  14. Bacteria of the human gut microbiome catabolize red seaweed glycans with carbohydrate-active enzyme updates from extrinsic microbes.

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    Hehemann, Jan-Hendrik; Kelly, Amelia G; Pudlo, Nicholas A; Martens, Eric C; Boraston, Alisdair B

    2012-11-27

    Humans host an intestinal population of microbes--collectively referred to as the gut microbiome--which encode the carbohydrate active enzymes, or CAZymes, that are absent from the human genome. These CAZymes help to extract energy from recalcitrant polysaccharides. The question then arises as to if and how the microbiome adapts to new carbohydrate sources when modern humans change eating habits. Recent metagenome analysis of microbiomes from healthy American, Japanese, and Spanish populations identified putative CAZymes obtained by horizontal gene transfer from marine bacteria, which suggested that human gut bacteria evolved to degrade algal carbohydrates-for example, consumed in form of sushi. We approached this hypothesis by studying such a polysaccharide utilization locus (PUL) obtained by horizontal gene transfer by the gut bacterium Bacteroides plebeius. Transcriptomic and growth experiments revealed that the PUL responds to the polysaccharide porphyran from red algae, enabling growth on this carbohydrate but not related substrates like agarose and carrageenan. The X-ray crystallographic and biochemical analysis of two proteins encoded by this PUL, BACPLE_01689 and BACPLE_01693, showed that they are β-porphyranases belonging to glycoside hydrolase families 16 and 86, respectively. The product complex of the GH86 at 1.3 Å resolution highlights the molecular details of porphyran hydrolysis by this new porphyranase. Combined, these data establish experimental support for the argument that CAZymes and associated genes obtained from extrinsic microbes add new catabolic functions to the human gut microbiome.

  15. Reduced Mass and Diversity of the Colonic Microbiome in Patients with Multiple Sclerosis and Their Improvement with Ketogenic Diet.

    Science.gov (United States)

    Swidsinski, Alexander; Dörffel, Yvonne; Loening-Baucke, Vera; Gille, Christoph; Göktas, Önder; Reißhauer, Anne; Neuhaus, Jürgen; Weylandt, Karsten-Henrich; Guschin, Alexander; Bock, Markus

    2017-01-01

    Background: Colonic microbiome is thought to be involved in auto-immune multiple sclerosis (MS). Interactions between diet and the colonic microbiome in MS are unknown. Methods: We compared the composition of the colonic microbiota quantitatively in 25 MS patients and 14 healthy controls.Fluorescence in situ hybridization (FISH) with 162 ribosomal RNA derived bacterial FISH probes was used. Ten of the MS patients received a ketogenic diet for 6 months. Changes in concentrations of 35 numerically substantial bacterial groups were monitored at baseline and at 2, 12, and 23/24 weeks. Results: No MS typical microbiome pattern was apparent.The total concentrations and diversity of substantial bacterial groups were reduced in MS patients ( P < 0.001). Bacterial groups detected with EREC (mainly Roseburia ), Bac303 ( Bacteroides ), and Fprau ( Faecalibacterium prausnitzii ) probes were diminished the most. The individual changes were multidirectional and inconsistent. The effects of a ketogenic diet were biphasic. In the short term, bacterial concentrations and diversity were further reduced. They started to recover at week 12 and exceeded significantly the baseline values after 23-24 weeks on the ketogenic diet. Conclusions: Colonic biofermentative function is markedly impaired in MS patients.The ketogenic diet normalized concentrations of the colonic microbiome after 6 months.

  16. Effect of lactose on gut microbiota and metabolome of infants with cow's milk allergy.

    Science.gov (United States)

    Francavilla, Ruggiero; Calasso, Maria; Calace, Laura; Siragusa, Sonya; Ndagijimana, Maurice; Vernocchi, Pamela; Brunetti, Luigia; Mancino, Giuseppe; Tedeschi, Giuseppe; Guerzoni, Elisabetta; Indrio, Flavia; Laghi, Luca; Miniello, Vito L; Gobbetti, Marco; De Angelis, Maria

    2012-08-01

    Allergic infants have an unusual gastrointestinal microbiota with low numbers of Bifidobacterium/Lactobacilli and high levels of Clostridium, staphylococci and Escherichia coli. Hydrolyzed formula used to treat these infants is deprived of lactose that instead may influence the gut microbial composition. The aim of the present study is to investigate the influence of lactose on the composition of the gut microbiota and metabolome of infants with cow's milk allergy. Infants prospectively enrolled received an extensively hydrolyzed formula with no lactose for 2 months followed by an identical lactose-containing formula for an additional 2 months. Healthy, age-gender-matched infants were used as controls. The following determinations were performed before and after the introduction of lactose in the diet: enumeration of cells present in the feces using FISH, counts of viable bacterial cells and gas-chromatography mass spectrometry/solid-phase microextraction analysis. The addition of lactose to the diet significantly increases the counts of Bifidobacteria and lactic acid bacteria (p lactose significantly increases the concentration of total short-chain fatty acids (p lactose to an extensively hydrolyzed formula is able to positively modulate the composition of gut microbiota by increasing the total fecal counts of Lactobacillus/Bifidobacteria and decreasing that of Bacteroides/Clostridia. The positive effect is completed by the increase of median concentration of short chain fatty acids, especially for acetic and butyric acids demonstrated by the metabolomic analysis. © 2012 John Wiley & Sons A/S.

  17. Intrauterine bacterial findings in postpartum cows with retained fetal membranes.

    Science.gov (United States)

    Bekana, M; Jonsson, P; Ekman, T; Kindahl, H

    1994-11-01

    Eleven Swedish postpartum cows with retained fetal membranes (RFM) were studied to determine the intrauterine bacterial flora. Bacteriological examination was performed from twice weekly uterine biopsies. A total of 161 biopsies were collected during the first 8 weeks postpartum of which 82 (50.9%) were found with bacterial growth. Seventy-one of the 82 bacteria-positive biopsies (86.6%) showed mixed infections whereas the remaining 11 (13.4%) were pure cultures. Generally, a total of 322 isolates belonging to 12 different genera of bacteria, 6 facultative and 6 obligate anaerobic pathogens were identified. Mixed infections were most frequent for Actinomyces pyogenes together with obligate anaerobic bacteria, especially Bacteroides levii/spp. and Fusobacterium necrophorum. All of the studied cows had an infection that involved the first two genera of bacteria, whereas F. necrophorum was found in 8 of the 11 animals. The present work suggests that a possible pathogenic synergism between A. pyogenes and the two main Gram-negative anaerobes might have caused early endometritis and/or persistent infection.

  18. Effect of Bifidobacterium breve on the Intestinal Microbiota of Coeliac Children on a Gluten Free Diet: A Pilot Study

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    Andrea Quagliariello

    2016-10-01

    Full Text Available Coeliac disease (CD is associated with alterations of the intestinal microbiota. Although several Bifidobacterium strains showed anti-inflammatory activity and prevention of toxic gliadin peptides generation in vitro, few data are available on their efficacy when administered to CD subjects. This study evaluated the effect of administration for three months of a food supplement based on two Bifidobacterium breve strains (B632 and BR03 to restore the gut microbial balance in coeliac children on a gluten free diet (GFD. Microbial DNA was extracted from faeces of 40 coeliac children before and after probiotic or placebo administration and 16 healthy children (Control group. Sequencing of the amplified V3-V4 hypervariable region of 16S rRNA gene as well as qPCR of Bidobacterium spp., Lactobacillus spp., Bacteroides fragilis group Clostridium sensu stricto and enterobacteria were performed. The comparison between CD subjects and Control group revealed an alteration in the intestinal microbial composition of coeliacs mainly characterized by a reduction of the Firmicutes/Bacteroidetes ratio, of Actinobacteria and Euryarchaeota. Regarding the effects of the probiotic, an increase of Actinobacteria was found as well as a re-establishment of the physiological Firmicutes/Bacteroidetes ratio. Therefore, a three-month administration of B. breve strains helps in restoring the healthy percentage of main microbial components.

  19. Effect of Probiotic (VSL#3 and Omega-3 on Lipid Profile, Insulin Sensitivity, Inflammatory Markers, and Gut Colonization in Overweight Adults: A Randomized, Controlled Trial

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    Hemalatha Rajkumar

    2014-01-01

    Full Text Available To evaluate the effects of probiotic (VSL#3 and omega-3 fatty acid on insulin sensitivity, blood lipids, and inflammation, we conducted a clinical trial in 60 overweight (BMI>25, healthy adults, aged 40–60 years. After initial screening the subjects were randomized into four groups with 15 per group. The four groups received, respectively, placebo, omega-3 fatty acid, probiotic VSL#3, or both omega-3 and probiotic, for 6 weeks. Blood and fecal samples were collected at baseline and after 6 weeks. The probiotic (VSL#3 supplemented group had significant reduction in total cholesterol, triglyceride, LDL, and VLDL and had increased HDL (P<0.05 value. VSL#3 improved insulin sensitivity (P<0.01, decreased hsCRP, and favorably affected the composition of gut microbiota. Omega-3 had significant effect on insulin sensitivity and hsCRP but had no effect on gut microbiota. Addition of omega-3 fatty acid with VSL#3 had more pronounced effect on HDL, insulin sensitivity and hsCRP. Subjects with low HDL, insulin resistance, and high hsCRP had significantly lower total lactobacilli and bifidobacteria count and higher E. coli and bacteroides count.

  20. Ecophysiological characterization of cultivable Antarctic psychrotolerant marine bacteria able to degrade hydrocarbons

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    De Domenico, M

    2005-11-01

    Full Text Available The basic understanding of both the physiology and ecology of psychrotolerant Antarctic bacteria is a crucial step for the optimization of their biodegradative activity in cold environments. The detection of cold-adapted hydrocarbon-degrading bacteria in Antarctic seawaters is certainly of great interest for bioremediative purpose in oil polluted marine Antarctic systems, where the introduction of non native species is not allowed. This study focused on psychrotolerant marine bacteria inhabiting an Antarctic coastal area directly influenced by the human activity at the Italian Research Station (Terra Nova Bay. Fifty bacterial strains were isolated from hydrocarbon-degrading enrichment cultures obtained from seawater samples collected in the inlet Road Bay (Ross Sea. A preliminary Restriction Fragment Length Polymorphism (RFLP analysis, carried out on 16S rDNA amplified via PCR using RSAI and AluI restriction enzymes, was applied to cluster the isolates according to the restriction profile they showed. One representative isolate per cluster was selected for further characterization; to elucidate their taxonomic position, conventional phenotypic and phylogenetic analyses were performed. Results led to the identification of the isolates as members of ten genera belonging to four phylogenetic groups: the alfa- and gamma-proteobacteria subdivisions, the gram-positive branch and the Cytophaga-Flexibacter-Bacteroides (CFB phylum. Results indicate a high degree of biodiversity within the peculiar ecophysiological group of the hydrocarbon-degrading marine bacteria.