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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. Tetracycline transport in Bacteroides fragilis.

    OpenAIRE

    Fayolle, F; Privitera, G; Sebald, M

    1980-01-01

    In susceptible strain of Bacteroides fragilis, tetracycline uptake is biphasic. The initial phase is independent of adenosine 5'-triphosphate synthesis, which is coupled to fumarate reduction; this phase is not altered by expression of tetracycline resistance genes in a resistant strain. The second phase appears to occur by active transport, since it is largely reduced by rotenone, an inhibitor of electron transport to fumarate; moreover, this phase is under negative control of the tetracycli...

  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. Serum antibodies to oral Bacteroides asaccharolyticus (Bacteroides gingivalis): relationship to age and periondontal disease.

    OpenAIRE

    Mouton, C; Hammond, P G; Slots, J; Genco, R J

    1981-01-01

    An enzyme-linked immunosorbent assay microplate method was used for measuring levels of antibody specific for the oral serotype of Bacteroides asaccharolyticus (Bacteroides gingivalis) in serum samples obtained from umbilical cords, infants, children, periodontally normal adults, and edentulous adults. Serum from patients with various periodontal diseases, including adult periodontitis, localized juvenile periodontitis, generalized juvenile periodontitis, post-localized juvenile periodontitis...

  5. Bacteroides species: maintenance of laboratory strains.

    OpenAIRE

    Baldwin, W W; Tseng, M; Landay, M E

    1981-01-01

    A medium composed of blood agar base (40 g/liter), yeast extract (5 g/liter), and cysteine hydrochloride (0.05 g/liter), completely filling screw-cap tubes (13 by 100 mm), can keep Bacteroides species alive for at least 10 months without refrigeration.

  6. Lectinlike adhesins in the Bacteroides fragilis group.

    OpenAIRE

    Rogemond, V; Guinet, R M

    1986-01-01

    Lectinlike adhesins were identified in the Bacteroides fragilis group by using sugars immobilized on agarose beads either with whole bacteria by direct microscopic examination or with soluble extracts by immunoaffinoelectrophoresis. These two methods allowed the identification of two sugars reacting with whole bacteria and with the corresponding extracts: alpha-D-glucosamine and D-galactosamine. Among eight strains tested representing seven species, the two strains of B. fragilis were equally...

  7. Monoclonal antibodies to Bacteroides fragilis lipopolysaccharide.

    OpenAIRE

    Linko-Kettunen, L; Arstila, P; Jalkanen, M; Jousimies-Somer, H; Lassila, O; Lehtonen, O P; Weintraub, A; Viljanen, M K

    1984-01-01

    Monoclonal antibodies (MoAbs) to the lipopolysaccharide (LPS) of Bacteroides fragilis were produced by immunizing mice before hybridization with bacterial outer membranes solubilized with Triton X-100. Nineteen stabile clones were established. They all produced antibodies that reacted more strongly with purified B. fragilis LPS than with crude sonicated antigen in an enzyme immunoassay. Four MoAbs were studied by immunoblotting and enzyme immunoassay inhibition. Immunoblotting confirmed that ...

  8. Localizations of aluminum in soybean bacteroids and seeds.

    OpenAIRE

    Roth, L. E.; Dunlap, J R; Stacey, G.

    1987-01-01

    Aluminum, long known to be detrimental to soybean productivity, was localized in the polyphosphate granules (PPG) of bacteroids in root nodules of soybean plants. By using energy-dispersive X-ray analysis, bacteroids in early infections were shown to have typical PPG constituents. However, in PPG in older infections and after the bacteroids were digested intracellularly, aluminum was also detected. These results indicate that aluminum accumulates in PPG after a period when organisms have been...

  9. Activities of Nigerian chewing stick extracts against Bacteroides gingivalis and Bacteroides melaninogenicus.

    OpenAIRE

    Rotimi, V. O.; Laughon, B E; Bartlett, J. G.; Mosadomi, H A

    1988-01-01

    The in vitro activities of extracts of Nigerian chewing sticks against Bacteroides gingivalis and B. melaninogenicus are presented. The greatest inhibitory action was produced by Serindeia werneckei, whereas Fagara zanthoxyloides produced no appreciable inhibitory effect. A generally good correlation was found between the killing curves and MICs. Only extracts of Anogeissus leiocarpus showed acute toxicity in mice.

  10. Activities of Nigerian chewing stick extracts against Bacteroides gingivalis and Bacteroides melaninogenicus.

    Science.gov (United States)

    Rotimi, V O; Laughon, B E; Bartlett, J G; Mosadomi, H A

    1988-04-01

    The in vitro activities of extracts of Nigerian chewing sticks against Bacteroides gingivalis and B. melaninogenicus are presented. The greatest inhibitory action was produced by Serindeia werneckei, whereas Fagara zanthoxyloides produced no appreciable inhibitory effect. A generally good correlation was found between the killing curves and MICs. Only extracts of Anogeissus leiocarpus showed acute toxicity in mice. PMID:2897830

  11. [The first metronidazole-resistant Bacteroides species isolated at Marmara University Hospital: Bacteroides thetaiotaomicron].

    Science.gov (United States)

    Toprak Ülger, Nurver; Sayın, Elvan; Soyad, Ad; Dane, Faysal; Söyletir, Güner

    2013-10-01

    Bacteroides species, the predominant constituents of the human intestinal microbiota can cause serious intraabdominal and postoperative wound infections and bacteremia. Moreover, these bacteria are more resistant to antimicrobial agents than the other anaerobes. The limited number of the antimicrobials, such as carbapenems, beta-lactam/beta-lactamase inhibitors and nitroimidazoles are highly effective in eliminating Bacteroides. However, a few metronidazole-resistant isolates have been reported from several countries recently. The nim genes (nim A-G) are suggested to be responsible for the majority of the metronidazole resistance. Here, we describe a metronidazole-resistant Bacteroides thetaiotaomicron isolated from a blood culture. A gram-negative obligate anaerobic rod was isolated from the postoperative 5th day blood culture of a 62-year-old male patient with adenocarcinoma of the pancreas head. The strain was identified as B.thetaiotaomicron by using a combination of conventional tests and commercially available biochemical kits. Antimicrobial susceptibility testing was performed by agar dilution method. The resistance genes were investigated by means of PCR using specific primer pairs for nim gene. The purified PCR product was sequenced and analyzed by comparison of the consensus sequences with GenBank sequences. The MIC for metronidazole was 16 mg/L. Although the strain was intermediate according the CLSI criteria, it was resistant (> 4 mg/L) according to EUCAST criteria. The isolate was nim gene positive, and nucleotide sequencing of the PCR product shared 100% similarity with nimE gene (emb |AM042593.1 |). On the other hand the isolate was susceptible to carbapenems and sulbactam-ampicillin. Following administration of ampicillin-sulbactam, the patient's fever disappeared after 24 hours. The clinical condition improved considerably and he was discharged at day 8. The patient was followed up at the medical oncology clinic; however he died due to disease

  12. Black-pigmented Bacteroides spp. in the human oral cavity.

    OpenAIRE

    Zambon, J J; Reynolds, H S; Slots, J

    1981-01-01

    Five healthy children under 6 years of age, five healthy adults, and 10 adult periodontitis patients were examined for the prevalence and distribution of black-pigmented Bacteroides in the oral cavity. A total of 13 samples was obtained from each individual, including four supragingival and four subgingival dental plaques, dental occlusal surface, buccal mucosa, dorsal tongue, tonsil, and whole saliva. Black-pigmented Bacteroides were recovered from nine adult periodontitis patients. Healthy ...

  13. Protein phosphorylation in Bradyrhizobium japonicum bacteroids and cultures.

    OpenAIRE

    Karr, D B; Emerich, D W

    1989-01-01

    Protein phosphorylation was demonstrated in Bradyrhizobium japonicum bacteroids in vivo and in cultures in vivo and in vitro. Comparison of in vivo-labeled phosphoproteins of bacteroids and of cultured cells showed differences in both the pattern and intensity of labeling. In cultured cells, comparison of the labeling patterns and intensities of in vivo- and in vitro-labeled phosphoproteins showed a number of similarities; however, several phosphoproteins were found only after one of the two ...

  14. 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....

  15. Carbon Metabolism Enzymes of Rhizobium tropici Cultures and Bacteroids.

    Science.gov (United States)

    Romanov, V I; Hernández-Lucas, I; Martínez-Romero, E

    1994-07-01

    We determined the activities of selected enzymes involved in carbon metabolism in free-living cells of Rhizobium tropici CFN299 grown in minimal medium with different carbon sources and in bacteroids of the same strain. The set of enzymatic activities in sucrose-grown cells suggests that the pentose phosphate pathway, with the participation of the Entner-Doudoroff pathway, is probably the primary route for sugar catabolism. In glutamate- and malate-grown cells, high activities of the gluconeogenic enzymes (phosphoenolpyruvate carboxykinase, fructose-6-phosphate aldolase, and fructose bisphosphatase) were detected. In bacteroids, isolated in Percoll gradients, the levels of activity for many of the enzymes measured were similar to those of malate-grown cells, except that higher activities of glucokinase, glucose-6-phosphate dehydrogenase, and NAD-dependent phosphogluconate dehydrogenase were detected. Phosphoglucomutase and UDP glucose pyrophosphorylase showed high and constant levels under all growth conditions and in bacteroids. PMID:16349319

  16. Bacteroides fragilis aortic arch pseudoaneurysm: case report with review

    Directory of Open Access Journals (Sweden)

    Yang Yu-Jen

    2008-05-01

    Full Text Available Abstract We present a case of 58-year-old woman with underlying diabetes mellitus, hepatitis C virus-related liver cirrhosis, and total hysterectomy for uterine myoma 11 moths ago, who was diagnosed ruptured aortic arch mycotic pseudoaneurysm after a certain period of survey for her unknown fever cause. After emergent surgery with prosthetic graft interposition, all her blood cultures and tissue cultures revealed pathogen with Bacteroides fragilis. Although mycotic aneurysms have been well described in literatures, an aneurysm infected solely with Bacteroides fragilis is unusual, with only eight similar cases in the literature. Here we reported the only female case with her specific clinical and management course and summarized all reported cases of mycotic aneurysm caused by Bacteroides fragilis to clarify their conditions and treatments, alert the difficulty in diagnosis, and importance of highly suspicious.

  17. Long-wave UV light fluorescence for identification of black-pigmented Bacteroides spp.

    OpenAIRE

    Slots, J; Reynolds, H S

    1982-01-01

    Black-pigmented Bacteroides strains were grown on blood agar, and the colonies were evaluated for fluorescence from long-wave UV light. Most test strains of Bacteroides melaninogenicus subsp. intermedius exhibited a brilliant red fluorescence. B. melaninogenicus subsp. melaninogenicus fluoresced mostly red-orange. Bacteroides asaccharolyticus showed a yellow or red fluorescence. The intensity of the Bacteroides fluorescence weakened when the black pigment of the colonies developed. In contras...

  18. Antigenic Studies of Oral and Nonoral Black-Pigmented Bacteroides Strains

    OpenAIRE

    Reed, Michael J; Slots, Jørgen; Mouton, Christian; Genco, Robert J.

    1980-01-01

    Antigens of several oral and nonoral strains of Bacteroides asaccharolyticus (proposed classification of oral B. asaccharolyticus, Bacteroides gingivalis), Bacteroides melaninogenicus subsp. intermedius, B. melaninogenicus subsp. melaninogenicus, and B. melaninogenicus subsp. levii were identified in soluble preparations obtained by sonication, autoclaving, and NaOH treatment of whole bacterial cells. The sonicate preparations contained the most complete representation of soluble antigens usi...

  19. Isolation and characterization of proteases from Bacteroides melaninogenicus.

    OpenAIRE

    Fujimura, S.; Nakamura, T.(International Center for Elementary Particle Physics and Department of Physics, The University of Tokyo, Tokyo, Japan)

    1981-01-01

    We isolated two types of intracellular proteases from a strain of Bacteroides melaninogenicus. These enzymes were extracted from cells by ultrasonic treatment and were partially purified. These two enzymes (proteases I and II) differed in molecular weight, heat stability, sensitivity to reducing agents, Km value, and optimum pH for activity.

  20. Soluble aldehyde dehydrogenase and metabolism of aldehydes by soybean bacteroids.

    OpenAIRE

    Peterson, J. B.; LaRue, T A

    1982-01-01

    A soluble aldehyde dehydrogenase (EC 1.2.1.3) was partially purified from Rhizobium japonicum bacteroids and from free-living R. japonicum 61A76. The enzyme was activated by NAD+, NADH, and dithiothreitol, and it reduced NAD(P)+. Acetaldehyde, propionaldehyde, butyraldehyde, benzaldehyde, and succinic semialdehyde were substrates. The Km for straight-chain aldehydes decreased with increasing carbon chain length. The aldehyde dehydrogenase was inhibited by 6-cyanopurine, but not by metronidazo...

  1. Bacteroides gingivalis vesicles bind to and aggregate Actinomyces viscosus.

    OpenAIRE

    Ellen, R P; Grove, D A

    1989-01-01

    Isolated Bacteroides gingivalis 2561 vesicles aggregated suspensions of Actinomyces viscosus and Actinomyces naeslundii of all taxonomy clusters. Vesicles bound near A. viscosus cell walls and among its surface fibrils. Tritiated vesicles bound slightly better to saliva-coated hydroxyapatite (SHA) than to SHA coated with A. viscosus; saturation was approached at the concentrations that were tested. Pretreatment of A. viscosus-coated SHA with vesicles impaired the subsequent adherence of B. gi...

  2. Trans locus inhibitors limit concomitant polysaccharide synthesis in the human gut symbiont Bacteroides fragilis

    OpenAIRE

    Chatzidaki-Livanis, Maria; Weinacht, Katja G.; Comstock, Laurie E.

    2010-01-01

    Bacteroides is an abundant genus of bacteria of the human intestinal microbiota. Bacteroides species synthesize a large number of capsular polysaccharides (PS), a biological property not shared with closely related oral species, suggesting importance for intestinal survival. Bacteroides fragilis, for example, synthesizes eight capsular polysaccharides per strain, each of which phase varies via inversion of the promoters located upstream of seven of the eight polysaccharide biosynthesis operon...

  3. The effect of environmental conditions on expression of Bacteroides fragilis and Bacteroides thetaiotaomicron C10 protease genes

    Directory of Open Access Journals (Sweden)

    Thornton Roibeard F

    2012-09-01

    Full Text Available Abstract Background Bacteroides fragilis and Bacteroides thetaiotaomicron are members of the normal human intestinal microbiota. However, both organisms are capable of causing opportunistic infections, during which the environmental conditions to which the bacteria are exposed change dramatically. To further explore their potential for contributing to infection, we have characterized the expression in B. thetaiotaomicron of four homologues of the gene encoding the C10 cysteine protease SpeB, a potent extracellular virulence factor produced by Streptococcus pyogenes. Results We identified a paralogous set of genes (btp genes in the B. thetaiotaomicron genome, that were related to C10 protease genes we recently identified in B. fragilis. Similar to C10 proteases found in B. fragilis, three of the B. thetaiotaomicron homologues were transcriptionally coupled to genes encoding small proteins that are similar in structural architecture to Staphostatins, protease inhibitors associated with Staphopains in Staphylococcus aureus. The expression of genes for these C10 proteases in both B. fragilis and B. thetaiotaomicron was found to be regulated by environmental stimuli, in particular by exposure to oxygen, which may be important for their contribution to the development of opportunistic infections. Conclusions Genes encoding C10 proteases are increasingly identified in operons which also contain genes encoding proteins homologous to protease inhibitors. The Bacteroides C10 protease gene expression levels are responsive to different environmental stimuli suggesting they may have distinct roles in the bacterial-host interaction.

  4. Plasmid-associated transfer of tetracycline resistance in Bacteroides ruminicola.

    OpenAIRE

    Flint, H J; Thomson, A. M.; Bisset, J

    1988-01-01

    Tetracycline resistance was transferred at frequencies between 10(-7) and 10(-6) per recipient cell in anaerobic matings between two strains of the strictly anaerobic rumen bacterium Bacteroides ruminicola. The donor strain, 223/M2/7, was a multiple-plasmid-bearing tetracycline-resistant strain from the ovine rumen, and the recipient, F101, was a rifampin-resistant mutant of B14, a bovine strain belonging to B. ruminicola subsp. brevis. Resistance transfer could occur in the presence of DNase...

  5. Protein phosphorylation in Bradyrhizobium japonicum bacteroids and cultures

    International Nuclear Information System (INIS)

    Protein phosphorylation was demonstrated in Bradyrhizobium japonicum bacteroids in vivo and in cultures in vivo and in vitro. Comparison of in vivo-labeled phosphoproteins of bacteroids and of cultured cells showed differences in both the pattern and intensity of labeling. In cultured cells, comparison of the labeling patterns and intensities of in vivo- and in vitro-labeled phosphoproteins showed a number of similarities; however, several phosphoproteins were found only after one of the two labeling conditions. The labeling intensity was time dependent in both in vivo and in vitro assays and was dependent on the presence of magnesium in in vitro assays. Differences in the rates of phosphorylation and dephosphorylation were noted for a number of proteins. The level of incorporation of 32P into protein was only 2% or less of the total phosphate accumulated during the in vivo labeling period. Several isolation and sample preparation procedures resulted in differences in labeling patterns. Phosphatase inhibitors and several potential metabolic effectors had negligible effects on the phosphorylation pattern. There were no significant changes in the phosphorylation patterns of cells cultured on mannitol, acetate, and succinate, although the intensity of the labeling did vary with the carbon source

  6. 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.

  7. Mobile genetic elements in the genus Bacteroides, and their mechanism(s) of dissemination

    OpenAIRE

    Nguyen, Mai; Vedantam, Gayatri

    2011-01-01

    Bacteroides spp organisms, the predominant commensal bacteria in the human gut have become increasingly resistant to many antibiotics. They are now also considered to be reservoirs of antibiotic resistance genes due to their capacity to harbor and disseminate these genes via mobile transmissible elements that occur in bewildering variety. Gene dissemination occurs within and from Bacteroides spp primarily by conjugation, the molecular mechanisms of which are still poorly understood in the gen...

  8. Design and evaluation of Bacteroides DNA probes for the specific detection of human fecal pollution.

    OpenAIRE

    Kreader, C A

    1995-01-01

    Because Bacteroides spp. are obligate anaerobes that dominate the human fecal flora, and because some species may live only in the human intestine, these bacteria might be useful to distinguish human from nonhuman sources of fecal pollution. To test this hypothesis, PCR primers specific for 16S rRNA gene sequences of Bacteroides distasonis, B. thetaiotaomicron, and B. vulgatus were designed. Hybridization with species-specific internal probes was used to detect the intended PCR products. Extr...

  9. A Peptidoglycan-Remodeling Enzyme Is Critical for Bacteroid Differentiation in Bradyrhizobium spp. During Legume Symbiosis.

    Science.gov (United States)

    Gully, Djamel; Gargani, Daniel; Bonaldi, Katia; Grangeteau, Cédric; Chaintreuil, Clémence; Fardoux, Joël; Nguyen, Phuong; Marchetti, Roberta; Nouwen, Nico; Molinaro, Antonio; Mergaert, Peter; Giraud, Eric

    2016-06-01

    In response to the presence of compatible rhizobium bacteria, legumes form symbiotic organs called nodules on their roots. These nodules house nitrogen-fixing bacteroids that are a differentiated form of the rhizobium bacteria. In some legumes, the bacteroid differentiation comprises a dramatic cell enlargement, polyploidization, and other morphological changes. Here, we demonstrate that a peptidoglycan-modifying enzyme in Bradyrhizobium strains, a DD-carboxypeptidase that contains a peptidoglycan-binding SPOR domain, is essential for normal bacteroid differentiation in Aeschynomene species. The corresponding mutants formed bacteroids that are malformed and hypertrophied. However, in soybean, a plant that does not induce morphological differentiation of its symbiont, the mutation does not affect the bacteroids. Remarkably, the mutation also leads to necrosis in a large fraction of the Aeschynomene nodules, indicating that a normally formed peptidoglycan layer is essential for avoiding the induction of plant immune responses by the invading bacteria. In addition to exopolysaccharides, capsular polysaccharides, and lipopolysaccharides, whose role during symbiosis is well defined, our work demonstrates an essential role in symbiosis for yet another rhizobial envelope component, the peptidoglycan layer. PMID:26959836

  10. Relative adherence of Bacteroides species and strains to Actinomyces viscosus on saliva-coated hydroxyapatite

    International Nuclear Information System (INIS)

    The study was designed to compare the adherence of several Bacteroides species to A. viscosus. Using 3H, we labeled 24 laboratory strains, including 13 Bacteroides species and 11 fresh clinical isolates of three Bacteroides species. Their adherence to A. viscosus bound to a saliva-coated mineral surface was quantified by liquid scintillation. Adherence relative to a standard strain, B. gingivalis 2561, was compared. Among the lab bacteroides, those of B. gingivalis (eight strains) were the greatest binders (mean, 80.5 ± 12.4%). Strains of other lab bacteroides bound less well (mean, 33.4 ± 6.3%). The difference in means was statistically significant (p less than 0.01). The mean for B. gingivalis strains was also significantly greater than that for strains of B. intermedius (51.7 ± 6.2%). Attachment of B. gingivalis was saturable in experiments in which either input concentration or time was the independent variable, indicating that B. gingivalis cells do not accumulate in this vitro simulation of plaque formation by binding to each other. Subculture did not seem to affect the degree of binding

  11. Disk diffusion susceptibility testing of the Bacteroides fragilis group.

    Science.gov (United States)

    Horn, R; Bourgault, A M; Lamothe, F

    1987-10-01

    The susceptibilities of 225 isolates of the Bacteroides fragilis group to six antibiotics were determined by a new disk diffusion test in Wilkins-Chalgren agar and by the standard agar dilution method. For disk diffusion, the bacteria were directly suspended in saline and immediately swabbed onto 15-cm agar plates. Disks of cefoxitin (30 micrograms), chloramphenicol (30 micrograms), clindamycin (2 micrograms), moxalactam (30 micrograms), imipenem (10 micrograms), and ticarcillin (75 micrograms) were applied, and the plates were incubated at 37 degrees C in an anaerobic atmosphere. Zone sizes were measured at 24 h. The results of disk diffusion and agar dilution were compared by regression analysis by the method of least squares and by the error rate-bounded method. Zones were easily measured for 216 strains (96%). The correlation between the MICs and diameters of inhibition for cefoxitin, clindamycin, moxalactam, and ticarcillin was generally good. A correlation could not be established for chloramphenicol and imipenem, as there were too few resistant strains. With the recommended resistance breakpoints, the following susceptible and resistant zone diameter breakpoints could be established: cefoxitin, less than or equal to 19 and greater than or equal to 21 mm; clindamycin, less than or equal to 14 and greater than or equal to 18 mm; moxalactam, less than or equal to 21 and greater than or equal to 25 mm; and ticarcillin, less than or equal to 15 and greater than or equal to 16 mm. By applying these zone criteria, the percentage of false-susceptible strains was less than 1% and of false-resistant strains was less than 4% for the drugs tested. PMID:3481247

  12. Transfer of clindamicyn resistance between Bacteroides fragilis group strains isolated from clinical specimens

    Directory of Open Access Journals (Sweden)

    Cibele B. Mano de Carvalho

    1998-09-01

    Full Text Available Clindamycin resistance was trasferred by a conjugation-like process from Bacteroides thetaiotaomicron 52, a multiple antibiotic-resistant strain isolated from clinical specimens, to other Bacteroides species. A possible association between a plasmid detected in the donor strain and clindamycin resistance is discussed.Resistência à clindamicina foi transferida através de processo semelhante à conjugação, de uma cepa multirresistente e isolada de espécime clínico, B. thetaiotaomicron 52, para outra espécie de Bacteroides. Uma possível associação entre um plasmídio detectado na cepa doadora e a resistência à clindamicina é discutida.

  13. Complete genome sequence of Bacteroides salanitronis type strain (BL78T)

    Energy Technology Data Exchange (ETDEWEB)

    Gronow, Sabine [DSMZ - German Collection of Microorganisms and Cell Cultures GmbH, Braunschweig, Germany; Held, Brittany [Los Alamos National Laboratory (LANL); Lucas, Susan [Joint Genome Institute, Walnut Creek, California; Lapidus, Alla L. [Joint Genome Institute, Walnut Creek, California; Glavina Del Rio, Tijana [Joint Genome Institute, Walnut Creek, California; Nolan, Matt [Joint Genome Institute, Walnut Creek, California; Tice, Hope [Joint Genome Institute, Walnut Creek, California; Deshpande, Shweta [Joint Genome Institute, Walnut Creek, California; Cheng, Jan-Fang [Joint Genome Institute, Walnut Creek, California; Pitluck, Sam [Joint Genome Institute, Walnut Creek, California; Liolios, Konstantinos [Joint Genome Institute, Walnut Creek, California; Pagani, Ioanna [Joint Genome Institute, Walnut Creek, California; Ivanova, N [U.S. Department of Energy, Joint Genome Institute; Mavromatis, K [U.S. Department of Energy, Joint Genome Institute; Pati, Amrita [U.S. Department of Energy, Joint Genome Institute; Tapia, Roxanne [Los Alamos National Laboratory (LANL); Han, Cliff [Los Alamos National Laboratory (LANL); Goodwin, Lynne A. [Los Alamos National Laboratory (LANL); Chen, Amy [Joint Genome Institute, Walnut Creek, California; Palaniappan, Krishna [Joint Genome Institute, Walnut Creek, California; Land, Miriam L [ORNL; Hauser, Loren John [ORNL; Chang, Yun-Juan [ORNL; Jeffries, Cynthia [Oak Ridge National Laboratory (ORNL); Brambilla, Evelyne-Marie [DSMZ - German Collection of Microorganisms and Cell Cultures GmbH, Braunschweig, Germany; Rohde, Manfred [HZI - Helmholtz Centre for Infection Research, Braunschweig, Germany; Goker, Markus [DSMZ - German Collection of Microorganisms and Cell Cultures GmbH, Braunschweig, Germany; Detter, J. Chris [Joint Genome Institute, Walnut Creek, California; Woyke, Tanja [Joint Genome Institute, Walnut Creek, California; Bristow, James [Joint Genome Institute, Walnut Creek, California; Markowitz, Victor [Joint Genome Institute, Walnut Creek, California; Hugenholtz, Philip [U.S. Department of Energy, Joint Genome Institute; Kyrpides, Nikos C [Joint Genome Institute, Walnut Creek, California; Klenk, Hans-Peter [DSMZ - German Collection of Microorganisms and Cell Cultures GmbH, Braunschweig, Germany; Eisen, Jonathan [Joint Genome Institute, Walnut Creek, California

    2011-01-01

    Bacteroides salanitronis Lan et al. 2006 is a species of the genus Bacteroides, which belongs to the family Bacteroidaceae. The species is of interest because it was isolated from the gut of a chicken and the growing awareness that the anaerobic microflora of the cecum is of benefit for the host and may impact poultry farming. The 4,308,663 bp long genome consists of a 4.24 Mbp chromosome and three plasmids (6 kbp, 19 kbp, 40 kbp) containing 3,737 protein-coding and 101 RNA genes and is a part of the Genomic Encyclopedia of Bacteria and Archaea project.

  14. A proteomic approach towards understanding the cross talk between Bacteroides fragilis and Bifidobacterium longum in coculture.

    Science.gov (United States)

    Rios-Covián, David; Sánchez, Borja; Martínez, Noelia; Cuesta, Isabel; Hernández-Barranco, Ana M; de Los Reyes-Gavilán, Clara G; Gueimonde, Miguel

    2016-07-01

    A better understanding of the interactions among intestinal microbes is needed to decipher the complex cross talk that takes place within the human gut. Bacteroides and Bifidobacterium genera are among the most relevant intestinal bacteria, and it has been previously reported that coculturing of these 2 microorganisms affects their survival. Therefore, coculturing of Bifidobacterium longum NB667 and Bacteroides fragilis DSMZ2151 was performed with the aim of unravelling the mechanisms involved in their interaction. To this end, we applied proteomic (2D-DIGE) analyses, and by chromatographic techniques we quantified the bacterial metabolites produced during coincubation. Coculture stimulated the growth of B. longum, retarding that of B. fragilis, with concomitant changes in the production of some proteins and metabolites of both bacteria. The combined culture promoted upregulation of the bifidobacterial pyruvate kinase and downregulation of the Bacteroides phosphoenolpyruvate carboxykinase - 2 enzymes involved in the catabolism of carbohydrates. Moreover, B. fragilis FKBP-type peptidyl-prolyl cis-trans isomerase, a protein with chaperone-like activity, was found to be overproduced in coculture, suggesting the induction of a stress response in this microorganism. This study provides mechanistic data to deepen our understanding of the interaction between Bacteroides and Bifidobacterium intestinal populations. PMID:27156738

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

    Science.gov (United States)

    Parajuli, Sunita; Siegfried, Justin; Dubrovskaya, Yanina; Rahimian, Joseph

    2016-01-01

    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. PMID:27418986

  16. Prevalence of Fragilysin Gene in Bacteroides fragilis Isolates from Blood and Other Extraintestinal Samples

    OpenAIRE

    Foulon, Ina; Piérard, Denis; Muyldermans, Gaëtan; Vandoorslaer, Kristof; Soetens, Oriane; Rosseel, Paul; Lauwers, Sabine

    2003-01-01

    Of 166 Bacteroides fragilis isolates, 26.2% of 103 isolates from blood and 20.6% of 63 extraintestinal isolates harbored the fragilysin gene (difference not statistically significant). Clinical characteristics and evolution were comparable in patients with B. fragilis bacteremia with or without this enterotoxin. Fragilysin seems not to be an important virulence factor in B. fragilis disease.

  17. 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.

  18. Extensive Mobilome-Driven Genome Diversification in Mouse Gut-Associated Bacteroides vulgatus mpk

    Science.gov (United States)

    Lange, Anna; Beier, Sina; Steimle, Alex; Autenrieth, Ingo B.; Huson, Daniel H.; Frick, Julia-Stefanie

    2016-01-01

    Like many other Bacteroides species, Bacteroides vulgatus strain mpk, a mouse fecal isolate which was shown to promote intestinal homeostasis, utilizes a variety of mobile elements for genome evolution. Based on sequences collected by Pacific Biosciences SMRT sequencing technology, we discuss the challenges of assembling and studying a bacterial genome of high plasticity. Additionally, we conducted comparative genomics comparing this commensal strain with the B. vulgatus type strain ATCC 8482 as well as multiple other Bacteroides and Parabacteroides strains to reveal the most important differences and identify the unique features of B. vulgatus mpk. The genome of B. vulgatus mpk harbors a large and diverse set of mobile element proteins compared with other sequenced Bacteroides strains. We found evidence of a number of different horizontal gene transfer events and a genome landscape that has been extensively altered by different mobilization events. A CRISPR/Cas system could be identified that provides a possible mechanism for preventing the integration of invading external DNA. We propose that the high genome plasticity and the introduced genome instabilities of B. vulgatus mpk arising from the various mobilization events might play an important role not only in its adaptation to the challenging intestinal environment in general, but also in its ability to interact with the gut microbiota. PMID:27071651

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

    OpenAIRE

    Hawkins Shawn A; Layton Alice C; Ripp Steven; Williams Dan; Sayler Gary S

    2008-01-01

    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.

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

    OpenAIRE

    Hawkins, Shawn A; Layton, Alice C.; Ripp, Steven; Williams, Dan; Sayler, Gary S.

    2008-01-01

    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.

  1. Identification of Bacteroides forsythus in subgingival plaque from patients with advanced periodontitis.

    OpenAIRE

    Gersdorf, H; Meissner, A.; Pelz, K; G. Krekeler; Göbel, U B

    1993-01-01

    Bacteroides forsythus has been associated with destructive adult periodontitis. Up to now, detailed analysis by classical means was hampered by the fastidious nature of the organism. There is hope that the application of molecular detection methods such as indirect immunofluorescence or in situ hybridization (ISH) will allow for more rapid and accurate identification. Here we describe a B. forsythus-specific probe (BFV530), complementary to 16S rRNA, which correctly identified all B. forsythu...

  2. The use of monoclonal antibodies to detect Bacteroides gingivalis in biological samples.

    OpenAIRE

    Chen, P; Bochacki, V; Reynolds, H S; Beanan, J; Tatakis, D.N.; Zambon, J J; Genco, R J

    1986-01-01

    Hybridomas were established which produce monoclonal antibodies specific for Bacteroides gingivalis, a pathogen associated with human periodontal disease. Spleen cells from BALB/c mice immunized with formalinized B. gingivalis were fused with Sp2/0-Ag14 myeloma cells. Of 1,050 wells with positive growth, 60 contained antibody reactive with the immunizing strain of B. gingivalis by enzyme-linked immunosorbent assay. Expansion of these cultures and cloning by limited dilution resulted in 28 clo...

  3. Adhesion of Actinomyces viscosus to Porphyromonas (Bacteroides) gingivalis-coated hexadecane droplets.

    OpenAIRE

    Rosenberg, M; Buivids, I A; Ellen, R P

    1991-01-01

    Interbacterial adhesion (coadhesion) is considered a major determinant of dental plaque ecology. In this report, we studied several aspects of the adhesion of Porphyromonas (Bacteroides) gingivalis to hexadecane in order to use the liquid hydrocarbon as a convenient substratum for coadhesion assays. Washed suspensions of hydrophobic P. gingivalis 2561 cells were vortexed with hexadecane to yield highly stable cell-coated droplets. Kinetics of coadhesion between Actinomyces viscosus cells and ...

  4. A Novel Tightly Regulated Gene Expression System for the Human Intestinal Symbiont Bacteroides thetaiotaomicron

    Science.gov (United States)

    Horn, Nikki; Carvalho, Ana L.; Overweg, Karin; Wegmann, Udo; Carding, Simon R.; Stentz, Régis

    2016-01-01

    There is considerable interest in studying the function of Bacteroides species resident in the human gastrointestinal (GI)-tract and the contribution they make to host health. Reverse genetics and protein expression techniques, such as those developed for well-characterized Escherichia coli cannot be applied to Bacteroides species as they and other members of the Bacteriodetes phylum have unique promoter structures. The availability of useful Bacteroides-specific genetic tools is therefore limited. Here we describe the development of an effective mannan-controlled gene expression system for Bacteroides thetaiotaomicron containing the mannan-inducible promoter–region of an α-1,2-mannosidase gene (BT_3784), a ribosomal binding site designed to modulate expression, a multiple cloning site to facilitate the cloning of genes of interest, and a transcriptional terminator. Using the Lactobacillus pepI as a reporter gene, mannan induction resulted in an increase of reporter activity in a time- and concentration-dependent manner with a wide range of activity. The endogenous BtcepA cephalosporinase gene was used to demonstrate the suitability of this novel expression system, enabling the isolation of a His-tagged version of BtCepA. We have also shown with experiments performed in mice that the system can be induced in vivo in the presence of an exogenous source of mannan. By enabling the controlled expression of endogenous and exogenous genes in B. thetaiotaomicron this novel inducer-dependent expression system will aid in defining the physiological role of individual genes and the functional analyses of their products. PMID:27468280

  5. Stability in Escherichia coli of an antibiotic resistance plasmid from Bacteroides fragilis.

    OpenAIRE

    Rashtchian, A; Booth, S J

    1981-01-01

    A Bacteroides fragilis strain resistant to penicillin G, tetracycline, and clindamycin was screened for the presence of plasmid deoxyribonucleic acid (DNA). Agarose gel electrophoresis of ethanol-precipitated DNA from cleared lysates of this strain revealed two plasmid DNA bands. The molecular weights of the plasmids were estimated by their relative mobility in agarose gel and compared with standard plasmids with known molecular weights. The molecular weights were 3.40 +/- 0.20 x 10(6) and 1....

  6. 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....

  7. Immunochemical and Biological Characterization of Three Capsular Polysaccharides from a Single Bacteroides fragilis Strain

    OpenAIRE

    Wiltrud M Kalka-Moll; Wang, Ying(School of Physics, Shandong University, Jinan, 250100, PR China); Comstock, L. E.; Gonzalez, Sylvia E.; Tzianabos, Arthur O.; Dennis L Kasper

    2001-01-01

    Although Bacteroides fragilis accounts for only 0.5% of the normal human colonic flora, it is the anaerobic species most frequently isolated from intra-abdominal and other infections with an intestinal source. The capsular polysaccharides of B. fragilis are part of a complex of surface polysaccharides and are the organism's most important virulence factors in the formation of intra-abdominal abscesses. Two capsular polysaccharides from strain NCTC 9343, PS A1 and PS B1, have been characterize...

  8. Evidence for T Cell-dependent Immunity to Bacteroides fragilis in an Intraabdominal Abscess Model

    OpenAIRE

    Onderdonk, Andrew B.; Markham, Richard B.; Zaleznik, Dori F.; Cisneros, Ronald L.; Dennis L Kasper

    1982-01-01

    It has been shown that active immunization of rats with the capsular polysaccharide of Bacteroides fragilis protects these animals against abscess development following intraperitoneal challenge with this species. Passive transfer of hyperimmune globulin from immunized animals to nonimmune recipients provided protection against B. fragilis bacteremia in challenged animals, but did not confer protection against abscess development. On the other hand, adoptive transfer of spleen cells from immu...

  9. Genetic evidence that outer membrane binding of starch is required for starch utilization by Bacteroides thetaiotaomicron.

    OpenAIRE

    Anderson, K.L.; Salyers, A A

    1989-01-01

    Mutagenesis of Bacteroides thetaiotaomicron with the transposon Tn4351 produced five classes of mutants that were not able to grow on amylose or amylopectin. These classes of mutants differed in their ability to grow on maltoheptaose (G7) and in the level of starch-degrading enzymes produced when bacteria were grown on maltose. All of the mutants were deficient in starch binding. Since one class of mutants retained normal levels of starch-degrading enzymes, this indicates that binding of the ...

  10. Oral implantation of Bacteroides asaccharolyticus and Eikenella corrodens in conventional hamsters.

    OpenAIRE

    Nagahata, T; Kiyoshige, T; Tomono, S; Abe, R; Sasaki, S.; Takazoe, I

    1982-01-01

    Oral implantation of Bacteroides asaccharolyticus 381-R' and Eikenella corrodens 1073S-R, which are highly resistant to streptomycin, was examined in conventional hamsters. The hamsters' first molars were ligatured with cotton threads preimmersed in bacterial suspensions. Bacterial inoculation was performed daily for 1 week, followed by a single weekly inoculation for 7 more weeks. Hamsters were fed Keyes' diet no. 2000 or ordinary powdered diet. Bacterial recovery, gingival histological chan...

  11. Formation of Novel Polysaccharides by Bradyrhizobium japonicum Bacteroids in Soybean Nodules

    OpenAIRE

    Streeter, John G.; Salminen, Seppo O.; Whitmoyer, Robert E.; Carlson, Russell W

    1992-01-01

    Certain strains of Bradyrhizobium japonicum form a previously unknown polysaccharide in the root nodules of soybean plants (Glycine max (L.) Merr.). The polysaccharide accumulates inside of the symbiosome membrane—the plant-derived membrane enclosing the bacteroids. In older nodules (60 days after planting), the polysaccharide occupies most of the symbiosome volume and symbiosomes become enlarged so that there is little host cytoplasm in infected cells. The two different groups of B. japonicu...

  12. Cephamycin inactivation due to enzymatic hydrolysis by beta-lactamase from Bacteroides fragilis.

    OpenAIRE

    Yotsuji, A; Minami, S; Kakizawa, H; Yasuda, T; Takai, A.; Saikawa, I; Inoue, M.; Mitsuhashi, S

    1985-01-01

    The susceptibility of 53 clinical isolates of Bacteroides fragilis to cephamycins was examined. Judging from the MICs for 50% of the strains tested, moxalactam was the most active, however, judging from the MICs for 90% of the strains tested, cefbuperazone was more effective than moxalactam. A correlation was observed between in vitro activity of benzylpenicillin and cephaloridine and beta-lactamase production. Inactivation due to enzymatic hydrolysis of cephamycins over a short time was not ...

  13. Purification and Comparison of the Periplasmic and Extracellular Forms of the Cellodextrinase from Bacteroides succinogenes

    OpenAIRE

    Huang, Li; Forsberg, Cecil W.

    1988-01-01

    Both the periplasmic and the extracellular cellodextrinases from Bacteroides succinogenes S85 grown on Avicel microcrystalline cellulose were purified to homogeneity by column chromatography and characterized. Over 70% of the total cellobiosidase activity displayed by cells was accounted for by these enzymes. The periplasmic and extracellular cellodextrinases had identical molecular weights (50,000), as determined by sodium dodecyl sulfate-polyacrylamide gel electrophoresis, and identical iso...

  14. Purification and characterization of an immunoglobulin A1 protease from Bacteroides melaninogenicus.

    OpenAIRE

    Mortensen, S B; Kilian, M

    1984-01-01

    Attention has recently been focused on bacterial proteases with the capacity to cleave immunoglobulin A (IgA proteases) as possible pathogenic factors in bacterial meningitis, gonorrhoea, and destructive periodontal disease. Here, we describe a method for the rapid purification of a specific IgA1 protease from Bacteroides melaninogenicus. The IgA1 protease was purified 6,172-fold with a yield of 9% by ammonium sulfate precipitation, DEAE-ion exchange chromatography, and separation on a prepar...

  15. 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.

  16. Development of new host-specific Bacteroides qPCRs for the identification of fecal contamination sources in water.

    Science.gov (United States)

    Gómez-Doñate, Marta; Casanovas-Massana, Arnau; Muniesa, Maite; Blanch, Anicet R

    2016-02-01

    Bacteroides spp. have been proposed as indicators of fecal contamination in microbial source tracking (MST) methodologies. The aim of this study was to develop new qPCR assays that target host-specific Bacteroidal 16S ribosomal RNA genes, to determine the source of fecal contamination in water. Denaturing gradient gel electrophoresis (DGGE) was used to select for host-specific bands of Bacteroides associated with a fecal pollution source and later to design four qPCR host-specific assays. A set of common primers for Bacteroides spp., four different Bacteroides spp. host-associated hydrolysis probes (human, cattle, pig, and poultry), and one hydrolysis probe for the Bacteroides genus were designed. This set of qPCR assays together with other previously developed Bacteroidetes MST targets were used to analyze water samples with fecal contamination from the four sources studied. The host-specific Bacteroides qPCRs designed for human (HMprobeBac), pig (PGprobeBac), and poultry (PLprobeBac) were highly specific for its sources (1.0, 0.97, and 1.0, respectively) although its sensitivity was lower (0.45, 0.50, and 0.73, respectively). The cattle-specific qPCR was totally unspecific and was discarded for future experiments. When compared to previously designed assays, the human and pig qPCRs showed better accuracies (0.86 and 0.84) than their counterparts HF183 and Pig-2-Bac (0.38 and 0.65). Thus, the newly designed human, pig, and poultry qPCR assays outperform other methods developed until date and may be useful for source tracking purposes. PMID:26763626

  17. Interactions between Bifidobacterium and Bacteroides species in cofermentations are affected by carbon sources, including exopolysaccharides produced by bifidobacteria.

    Science.gov (United States)

    Rios-Covian, David; Arboleya, Silvia; Hernandez-Barranco, Ana M; Alvarez-Buylla, Jorge R; Ruas-Madiedo, Patricia; Gueimonde, Miguel; de los Reyes-Gavilan, Clara G

    2013-12-01

    Cocultures of strains from two Bifidobacterium and two Bacteroides species were performed with exopolysaccharides (EPS) previously purified from bifidobacteria, with inulin, or with glucose as the carbon source. Bifidobacterium longum NB667 and Bifidobacterium breve IPLA20004 grew in glucose but showed poor or no growth in complex carbohydrates (inulin, EPS E44, and EPS R1), whereas Bacteroides grew well in the four carbon sources tested. In the presence of glucose, the growth of Bacteroides thetaiotaomicron DSM-2079 was inhibited by B. breve, whereas it remained unaffected in the presence of B. longum. Ba. fragilis DSM-2151 contributed to a greater survival of B. longum, promoting changes in the synthesis of short-chain fatty acids (SCFA) and organic acids in coculture with respect to monocultures. In complex carbohydrates, cocultures of bifidobacterium strains with Ba. thetaiotaomicron did not modify the behavior of Bacteroides nor improve the poor growth of bifidobacteria. The metabolic activity of Ba. fragilis in coculture with bifidobacteria was not affected by EPS, but greater survival of bifidobacteria at late stages of incubation occurred in cocultures than in monocultures, leading to a higher production of acetic acid than in monocultures. Therefore, cocultures of Bifidobacterium and Bacteroides can behave differently against fermentable carbohydrates as a function of the specific characteristics of the strains from each species. These results stress the importance of considering specific species and strain interactions and not simply higher taxonomic divisions in the relationship among intestinal microbial populations and their different responses to probiotics and prebiotics. PMID:24077708

  18. Purification and properties of Bacteroides heparinolyticus heparinase (heparin lyase, EC 4.2.2.7).

    OpenAIRE

    Nakamura, T.(International Center for Elementary Particle Physics and Department of Physics, The University of Tokyo, Tokyo, Japan); Shibata, Y.; Fujimura, S.

    1988-01-01

    Heparinase (heparin lyase, EC 4.2.2.7) was isolated from the cell extract of an oral bacterium, Bacteroides heparinolyticus. It was a basic protein with an isoelectric point of 9.5. Its molecular weight was 63,000. The enzyme was the most active against heparin among the tested mucopolysaccharides. Catalytic properties may be similar to those of heparinase of Flavobacterium heparinum, since the enzymatic degradation products obtained by using the two enzymes were the same on the basis of pape...

  19. Intracellular glycosidases of human colon Bacteroides ovatus B4-11.

    OpenAIRE

    Reddy, N R; Palmer, J K; Pierson, M. D.; Bothast, R J

    1984-01-01

    Activity of various glycosidases in the intracellular enzyme fraction of Bacteroides ovatus B4-11 was investigated. During 120 h of incubation at 37 degrees C, ca. 30% of the crude hemicellulose was hydrolyzed by an intracellular enzyme fraction of strain B4-11. Xylose was the major sugar released from crude hemicellulose. Glycosidases (alpha-1,6-glucosidase, alpha-1,4-glucosidase, beta-1,4-glucosidase, and beta-1,4-xylosidase) were induced in B. ovatus B4-11 by crude hemicellulose and hetero...

  20. Molecular cloning and sequencing of the gene encoding the fimbrial subunit protein of Bacteroides gingivalis.

    OpenAIRE

    Dickinson, D P; Kubiniec, M A; Yoshimura, F; Genco, R J

    1988-01-01

    The gene encoding the fimbrial subunit protein of Bacteroides gingivalis 381, fimbrilin, has been cloned and sequenced. The gene was present as a single copy on the bacterial chromosome, and the codon usage in the gene conformed closely to that expected for an abundant protein. The predicted size of the mature protein was 35,924 daltons, and the secretory form may have had a 10-amino-acid, hydrophilic leader sequence similar to the leader sequences of the MePhe fimbriae family. The protein se...

  1. Fermentation of fenugreek fiber, psyllium husk, and wheat bran by Bacteroides ovatus V975.

    Science.gov (United States)

    Al-Khaldi, S F; Martin, S A; Prakash, L

    1999-10-01

    The objective of this study was to evaluate the ability of the human colonic bacterium Bacteroides ovatus V975 to ferment fenugreek fiber (Fenufibers), psyllium husk (Metamucil), and wheat bran (Wheat Chex). Strain V975 was incubated in basal medium that contained 0.1 g of each fiber source for 0, 24, or 48 h. Little digestion of either fiber source was detected over 48 h, and little acetate or succinate was produced. From the lack of significant fiber digestion and fermentation by B. ovatus, it seems that all three fiber sources could be used as dietary supplements to increase roughage in the human diet. PMID:10486060

  2. 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 of......The human gut is extremely densely inhabited by bacteria mainly from two phyla, Bacteroidetes and Firmicutes, and there is a great interest in analyzing whole-genome sequences for these species because of their relation to human health and disease. Here, we do whole-genome comparison of 105...... other Bacteroides species, based on analysis of 16S rRNA sequence, whole-genome protein families and functional content, 16S rRNA sequences of the two species suggest that they belong to the Firmicutes phylum. We have presented a more detailed and precise description of the phylogenetic relationships of...

  3. Activation of Bacteroides fragilis toxin by a novel bacterial protease contributes to anaerobic sepsis in mice.

    Science.gov (United States)

    Choi, Vivian M; Herrou, Julien; Hecht, Aaron L; Teoh, Wei Ping; Turner, Jerrold R; Crosson, Sean; Bubeck Wardenburg, Juliane

    2016-05-01

    Bacteroides fragilis is the leading cause of anaerobic bacteremia and sepsis. Enterotoxigenic strains that produce B. fragilis toxin (BFT, fragilysin) contribute to colitis and intestinal malignancy, yet are also isolated in bloodstream infection. It is not known whether these strains harbor unique genetic determinants that confer virulence in extra-intestinal disease. We demonstrate that BFT contributes to sepsis in mice, and we identify a B. fragilis protease called fragipain (Fpn) that is required for the endogenous activation of BFT through the removal of its auto-inhibitory prodomain. Structural analysis of Fpn reveals a His-Cys catalytic dyad that is characteristic of C11-family cysteine proteases that are conserved in multiple pathogenic Bacteroides spp. and Clostridium spp. Fpn-deficient, enterotoxigenic B. fragilis has an attenuated ability to induce sepsis in mice; however, Fpn is dispensable in B. fragilis colitis, wherein host proteases mediate BFT activation. Our findings define a role for B. fragilis enterotoxin and its activating protease in the pathogenesis of bloodstream infection, which indicates a greater complexity of cellular targeting and activity of BFT than previously recognized. The expression of fpn by both toxigenic and nontoxigenic strains suggests that this protease may contribute to anaerobic sepsis in ways that extend beyond its role in toxin activation. It could thus potentially serve as a target for disease modification. PMID:27089515

  4. Heterogeneity in resistant fecal Bacteroides fragilis group collected from healthy people.

    Science.gov (United States)

    Narimani, T; Douraghi, M; Owlia, P; Rastegar, A; Esghaei, M; Nasr, B; Talebi, M

    2016-06-01

    Normal nonpathogenic flora would represent a constant lake of resistance genes potentially transferable to human pathogens. To assess the prevalence of resistance genes and genetic variability of Bacteroides fragilis group (BFG) from normal flora, 177 Bacteroides isolates obtained from the fecal samples of healthy individuals. These isolates were subjected to antibiotic susceptibility testing and pulsed field gel electrophoresis (PFGE). The isolates were further tested for the presence of ermF, tetQ and bft genes by PCR. Our results indicated the presence of different clonal strains (1 common type and 57 single types) among the resistant isolates. The resistance rate for the six antibiotics in this study was between 1% and 95%. Most of the isolates (99%) were susceptible to metronidazole. ermF and tetQ were detected in all erythromycin and tetracycline resistant isolates. None of the isolates were carried bft gene. These data suggest dissemination of heterogenic clonal groups in healthy persons and resistance to 5 high commonly used antibiotics. PMID:26945562

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

    Directory of Open Access Journals (Sweden)

    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.

  6. Identification and Phylogeny of the First T Cell Epitope Identified from a Human Gut Bacteroides Species.

    Directory of Open Access Journals (Sweden)

    Maria Elisa Perez-Muñoz

    Full Text Available Host T cell reactivity toward gut bacterial epitopes has been recognized as part of disease pathogenesis. However, the specificity of T cells that recognize this vast number of epitopes has not yet been well described. After colonizing a C57BL/6J germ-free mouse with the human gut symbiotic bacteria Bacteroides thetaiotaomicron, we isolated a T cell that recognized these bacteria in vitro. Using this T cell, we mapped the first known non-carbohydrate T cell epitope within the phylum Bacteroidetes. The T cell also reacted to two other additional Bacteroides species. We identified the peptide that stimulated the T cell by using a genetic approach. Genomic data from the epitope-positive and epitope-negative bacteria explain the cross-reactivity of the T cell to multiple species. This epitope degeneracy should shape our understanding of the T cell repertoire stimulated by the complex microbiome residing in the gastrointestinal tract in both healthy and disease states.

  7. Safety Assessment of Bacteroides uniformis CECT 7771 Isolated from Stools of Healthy Breast-Fed Infants.

    Directory of Open Access Journals (Sweden)

    M Leonor Fernández-Murga

    Full Text Available Bacteroides uniformis CECT 7771 is a potential probiotic strain, originally isolated from the stools of healthy breast-feed infants. The strain showed pre-clinical efficacy in a mouse obesity model. The objective of this study was to evaluate its potential toxicity and translocation ability after acute oral administration to mice.A safety study was conducted in immunocompetent and immunosuppressed C57BL-6 mice. Both mouse groups (n = 10 per group were fed orally 2 x 10(9 colony forming units (cfu/day of B. uniformis CECT 7771 or placebo by gavage for 6 days. Throughout this time, feed and water intake and body weight were monitored. Afterwards, mice were sacrificed and biological samples were collected to analyze blood and urine biochemistry, inflammatory and immune markers; gut mucosal histology and bacterial translocation to peripheral tissues. The results demonstrated that acute ingestion of this Bacteroides strain had no adverse effects on the animals' general health status or food intake, nor did it affect biochemical indicators of liver, kidney and pancreatic function or gut mucosal histology. Findings also demonstrated that administration did not lead to bacterial translocation to blood, liver or mesenteric lymph nodes. B. uniformis CECT 7771 also downregulated gene and protein expression (iNOS and PPAR-γ and inflammatory cytokines induced by immunosuppression.The findings indicate that the acute oral consumption of B. uniformis CECT 7771 does not raise safety concerns in mice. Further studies in humans should be conducted.

  8. 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.

  9. 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

  10. Bacteroides fragilis interferes with iNOS activity and leads to pore formation in macrophage surface

    International Nuclear Information System (INIS)

    Bacteroides fragilis is the anaerobe most commonly recoverable from clinical specimens. The wide genetic diversity of this bacterium related with virulence potential is still an open question. In this study, we analyzed the morphological aspects and microbicide action of MO during interactions with B. fragilis. A filamentous cytoplasm content release and a different actin organization colocalized with iNOS were detected. It was also possible to observe the reduction of NO production in the same conditions. The scanning electron microscopy showed the formation of pore-like structures in the surface of macrophages in the bacterial presence and by transmission electron microscopy we could observe the extrusion of cytoplasm contents as well as the condensation of chromatin in the nucleus periphery. These data suggest the existence of an inhibitory mechanism developed by B. fragilis strains for one of the macrophage microbicide actions

  11. Prevalence and antibiotic susceptibility of Bacteroides fragilis group isolated from stool samples in North Lebanon

    Directory of Open Access Journals (Sweden)

    Mariam Yehya

    2013-09-01

    Full Text Available Fifty one strains of the Bacteroides fragilis group were isolated from 45 fecal samples. Classical phenotypic identification showed that 16 isolates were B. thetaiotaomicron, 12 B. uniformis, 9 B. eggerthii,7 B. vulgatus,3 B. caccae,2 Parabacteroides distasonis with 1 identified B. ovatus and 1 B. fragilis. The 51 strains were tested for susceptibility against 16 antimicrobial agents and the MICs for metronidazole were determined. The tests showed that imipenem, meropenem and chloram-phenicol were the most effective antibiotics (98%, 98% and 92.16% of susceptibility, respectively followed by ticarcillin/clavulanic acid, piperacillin/tazobactam, rifampin (88.24% susceptibility, moxifloxacin 86.27% and tigecycline 84.31%. Ofloxacin and cefotaxime were the least effective antibiotics with 27.45% and 0% of activity respectively. Only six of the 51 isolated strains were resistant to metronidazole with MICs = 64 mg/L (1 strain and > 256 mg/L (5 strains.

  12. Bacteroides fragilis induce necrosis on mice peritoneal macrophages: In vitro and in vivo assays

    Energy Technology Data Exchange (ETDEWEB)

    Vieira, J.M.B.D., E-mail: jmanya@terra.com.br [Laboratorio de Tecnologia em Cultura de Celulas, UEZO, Rio de Janeiro (Brazil); Laboratorio de Biologia de Anaerobios, IMPPG, UFRJ, Rio de Janeiro (Brazil); Seabra, S.H. [Laboratorio de Tecnologia em Cultura de Celulas, UEZO, Rio de Janeiro (Brazil); Vallim, D.C. [Instituto Oswaldo Cruz, Rio de Janeiro (Brazil); Americo, M.A.; Fracallanza, S.E.L. [Laboratorio de Bacteriologia Medica, IMPPG, UFRJ, Rio de Janeiro (Brazil); Vommaro, R.C. [Laboratorio de Ultra-estrutura Celular Hertha Meyer, IBCCF, UFRJ (Brazil); Domingues, R.M.C.P. [Laboratorio de Biologia de Anaerobios, IMPPG, UFRJ, Rio de Janeiro (Brazil)

    2009-10-02

    Bacteroides fragilis is an anaerobic bacteria component of human intestinal microbiota and agent of infections. In the host B. fragilis interacts with macrophages, which produces toxic radicals like NO. The interaction of activated mice peritoneal macrophages with four strains of B. fragilis was evaluated on this study. Previously was shown that such strains could cause metabolic and morphologic alterations related to macrophage death. In this work propidium iodide staining showed the strains inducing macrophage necrosis in that the labeling was evident. Besides nitroblue tetrazolium test showed that B. fragilis stimulates macrophage to produce oxygen radicals. In vivo assays performed in BalbC mice have results similar to those for in vitro tests as well as scanning electron microscopy, which showed the same surface pore-like structures observed in vitro before. The results revealed that B. fragilis strains studied lead to macrophage death by a process similar to necrosis.

  13. Bacteroides fragilis induce necrosis on mice peritoneal macrophages: In vitro and in vivo assays

    International Nuclear Information System (INIS)

    Bacteroides fragilis is an anaerobic bacteria component of human intestinal microbiota and agent of infections. In the host B. fragilis interacts with macrophages, which produces toxic radicals like NO. The interaction of activated mice peritoneal macrophages with four strains of B. fragilis was evaluated on this study. Previously was shown that such strains could cause metabolic and morphologic alterations related to macrophage death. In this work propidium iodide staining showed the strains inducing macrophage necrosis in that the labeling was evident. Besides nitroblue tetrazolium test showed that B. fragilis stimulates macrophage to produce oxygen radicals. In vivo assays performed in BalbC mice have results similar to those for in vitro tests as well as scanning electron microscopy, which showed the same surface pore-like structures observed in vitro before. The results revealed that B. fragilis strains studied lead to macrophage death by a process similar to necrosis.

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

    Science.gov (United States)

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

    2015-02-01

    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/clavulanic acid, cefoxitin, clindamycin, imipenem, metronidazole, moxifloxacin, piperacillin/tazobactam, tigecycline by agar dilution method previously. The inhibition zones of the same antibiotics including meropenem disc were determined by the disc diffusion on Brucella blood agar supplemented with haemin and vitamin K1. Plates were incubated at 37 °C in an anaerobic atmosphere for 24 h. The zone diameters were read at 100% inhibition. In case of discrepant results MICs were determined by gradient test and compared with the inhibition zones on the same plate. We found a good agreement between the inhibition zone diameters and the MICs for imipenem, metronidazole, moxifloxacin and tigecyclin. The inhibition zone diameters of meropenem also separated clearly the isolates, which can be considered wild-type isolates. In case of amoxicillin/clavulanic acid and piperacillin/tazobactam intermediate and susceptible isolates according to the MIC determination, overlap during the zone diameter determination. Isolates with an inhibition zone disk diffusion can be an option for susceptibility testing of B. fragilis group isolates for most relevant antibiotics in routine laboratories. PMID:25464140

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

    International Nuclear Information System (INIS)

    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 3H-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

  16. Labeling of carbon pools in Bradyrhizobium japonicum and Rhizobium leguminosarum bv viciae bacteroids following incubation of intact nodules with 14CO2

    International Nuclear Information System (INIS)

    The aim of the work reported here was to ascertain that the patterns of labeling seen in isolated bacteroids also occurred in bacteroids in intact nodules and to observe early metabolic events following exposure of intact nodules to 14CO2. Intact nodules of soybean (Glycine max L. Merr. cv Ripley) inoculated with Bradyrhizobium japonicum USDA 110 and pea (Pisum sativum L. cv Progress 9) inoculated with Rhizobium leguminosarum by viciae isolate 128C53 were detached and immediately fed 14CO2 for 1 to 6 min. Bacteroids were purified from these nodules in 5 to 7 min after the feeding period. In the cytosol from both soybean and pea nodules, malate had the highest radioactivity, followed by citrate and aspartate. In peas, asparagine labeling equaled that of aspartate. In B. japonicum bacteroids, malate was the most rapidly labeled compound, and the rate of glutamate labeling was 67% of the rate of malate labeling. Aspartate and alanine were the next most rapidly labeled compounds. R. leguminosarum bacteroids had very low amounts of 14C and, after a 1-min feeding, malate contained 90% of the radioactivity in the organic acid fraction. Only a trace of activity was found in aspartate, whereas the rate of glutamate and alanine labeling approached that of malate after 6 min of feeding. Under the conditions studied, malate was the major form of labeled carbon supplied to both types of bacteroids. These results with intact nodules confirm our earlier results with isolated bacteroids, which showed that a significant proportion of provided labeled substrate, such as malate, is diverted to glutamate. This supports the conclusion that microaerobic conditions in nodules influence carbon metabolism in bacteroids. (author)

  17. Cryptic tetracycline resistance determinant (class F) from Bacteroides fragilis mediates resistance in Escherichia coli by actively reducing tetracycline accumulation.

    OpenAIRE

    Park, B. H.; Hendricks, M; Malamy, M H; Tally, F P; Levy, S. B.

    1987-01-01

    Escherichia coli bearing a cryptic tetracycline resistance determinant from Bacteroides fragilis expressed low-level constitutive resistance to tetracycline under aerobic, but not anaerobic, growth conditions and accumulated less tetracycline aerobically than did isogenic susceptible cells. This decreased uptake was energy dependent and reversible by increased concentrations of tetracycline, suggesting a saturable carrier-mediated active efflux mechanism. Decreased uptake was not seen when th...

  18. Tetracycline-inducible transfer of tetracycline resistance in Bacteroides fragilis in the absence of detectable plasmid DNA.

    OpenAIRE

    Rashtchian, A; Dubes, G R; Booth, S J

    1982-01-01

    Tetracycline resistance of three Bacteroides fragilis strains was shown to be inducible by subinhibitory concentrations of tetracycline. Tetracycline resistance markers could be transferred to another B. fragilis strain by filter mating. The transferability was inducible by subinhibitory concentrations of tetracycline and did not take place in the absence of tetracycline. The optimum concentration of tetracycline for induction of transfer was about 2 microgram/ml. The transfer was shown to be...

  19. 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...

  20. Thioredoxin Reductase Is Essential for Thiol/Disulfide Redox Control and Oxidative Stress Survival of the Anaerobe Bacteroides fragilis▿ †

    OpenAIRE

    Rocha, Edson R.; Tzianabos, Arthur O; Smith, C. Jeffrey

    2007-01-01

    Results of this study showed that the anaerobic, opportunistic pathogen Bacteroides fragilis lacks the glutathione/glutaredoxin redox system and possesses an extensive number of putative thioredoxin (Trx) orthologs. Analysis of the genome sequence revealed six Trx orthologs and an absence of genes required for synthesis of glutathione and glutaredoxins. In addition, it was shown that the thioredoxin reductase (TrxB)/Trx system is the major or sole redox system for thiol/disulfide cellular hom...

  1. Characterization of Four Outer Membrane Proteins Involved in Binding Starch to the Cell Surface of Bacteroides thetaiotaomicron

    OpenAIRE

    Shipman, Joseph A.; Berleman, James E.; Salyers, Abigail A.

    2000-01-01

    Bacteroides thetaiotaomicron, a gram-negative obligate anaerobe, utilizes polysaccharides by binding them to its cell surface and allowing cell-associated enzymes to hydrolyze them into digestible fragments. We use the starch utilization system as a model to analyze the initial steps involved in polysaccharide binding and breakdown. In a recent paper, we reported that one of the outer membrane proteins involved, SusG, had starch-degrading activity but was not sufficient for growth on starch. ...

  2. Physiological Characterization of SusG, an Outer Membrane Protein Essential for Starch Utilization by Bacteroides thetaiotaomicron

    OpenAIRE

    Shipman, Joseph A.; Cho, Kyu Hong; Siegel, Hilary A.; Salyers, Abigail A.

    1999-01-01

    Results from previous studies had suggested that Bacteroides thetaiotaomicron utilizes starch by binding the polysaccharide to the bacterial surface and subsequently degrading the polymer by using cell-associated enzymes. Most of the starch-degrading activity was localized to the periplasm, but a portion appeared to be membrane associated. This raised the possibility that some breakdown might occur in the outer membrane prior to exposure of the polysaccharide to the periplasmic polysaccharide...

  3. Therapeutic evaluation of difloxacin (A-56619) and A-56620 for experimentally induced Bacteroides fragilis-associated intra-abdominal abscess.

    OpenAIRE

    Thadepalli, H; Gollapudi, S V; Chuah, S K

    1986-01-01

    Difloxacin (A-56619) and A-56620, two novel fluoroquinolones, were tested in comparison with ciprofloxacin, cefoxitin, and combined clindamycin and gentamicin in the treatment of experimentally induced intraabdominal abscess associated with Bacteroides fragilis. Difloxacin was found to be as effective as clindamycin-gentamicin. A-56620, despite achieving subtherapeutic levels in serum, was found to be as effective as cefoxitin. Both difloxacin and A-56620 were effective in vivo against experi...

  4. Mutation of the Zinc-Binding Metalloprotease Motif Affects Bacteroides fragilis Toxin Activity but Does Not Affect Propeptide Processing

    OpenAIRE

    Franco, Augusto A.; Buckwold, Simy L.; Shin, Jai W.; Ascon, Miguel; Sears, Cynthia L.

    2005-01-01

    To evaluate the role of the zinc-binding metalloprotease in Bacteroides fragilis toxin (BFT) processing and activity, the zinc-binding consensus sequences (H348, E349, H352, G355, H358, and M366) were mutated by site-directed-mutagenesis. Our results indicated that single point mutations in the zinc-binding metalloprotease motif do not affect BFT processing but do reduce or eliminate BFT biologic activity in vitro.

  5. Mutation of the Zinc-Binding Metalloprotease Motif Affects Bacteroides fragilis Toxin Activity but Does Not Affect Propeptide Processing

    Science.gov (United States)

    Franco, Augusto A.; Buckwold, Simy L.; Shin, Jai W.; Ascon, Miguel; Sears, Cynthia L.

    2005-01-01

    To evaluate the role of the zinc-binding metalloprotease in Bacteroides fragilis toxin (BFT) processing and activity, the zinc-binding consensus sequences (H348, E349, H352, G355, H358, and M366) were mutated by site-directed-mutagenesis. Our results indicated that single point mutations in the zinc-binding metalloprotease motif do not affect BFT processing but do reduce or eliminate BFT biologic activity in vitro. PMID:16041055

  6. Use of abundance ratios of somatic coliphages and bacteriophages of Bacteroides thetaiotaomicron GA17 for microbial source identification.

    Science.gov (United States)

    Muniesa, Maite; Lucena, Francisco; Blanch, Anicet R; Payán, Andrey; Jofre, Juan

    2012-12-01

    Water contaminated with human faeces is a risk to human health and management of water bodies can be improved by determining the sources of faecal pollution. Field studies show that existing methods are insufficient and that different markers are required. This study proposes the combined use of two microbial indicators, the concentrations of which are presented as ratios. This provides a more reliable approach to identifying faecal sources as it avoids variation due to treatment or ageing of the contamination. Among other indicators, bacteriophages have been proposed as rapid and cheap indicators of faecal pollution. Samples analysed in this study were derived from wastewater treatment plants (raw sewage, secondary and tertiary effluents and raw sewage sludge) river water, seawater and animal related wastewater. The abundance ratios of faecal coliforms and Bacteroides phages, either strain RYC2056 (non-specific for faecal origin) or strain GA17 (specific for human pollution), and among somatic coliphages and phages infecting both Bacteroides strains, were evaluated. The results indicate that the ratio of somatic coliphages and phages infecting Bacteroides strain GA17, which is specific to human faecal sources, provides a robust method for discriminating samples, even those presenting different levels and ages of pollution, and allows samples polluted with human faeces to be distinguished from those containing animal faecal pollution. This method allows the generation of numerical data that can be further applied to numerical methods for faecal pollution discrimination. PMID:23039916

  7. Differential proteomic analysis of outer membrane enriched extracts of Bacteroides fragilis grown under bile salts stress.

    Science.gov (United States)

    Boente, Renata F; Pauer, Heidi; Silva, Deborah N S; Filho, Joaquim Santos; Sandim, Vanessa; Antunes, Luis Caetano M; Ferreira, Rosana Barreto Rocha; Zingali, Russolina B; Domingues, Regina M C P; Lobo, Leandro A

    2016-06-01

    Bacteroides fragilis is the most commonly isolated anaerobic bacteria from infectious processes. Several virulence traits contribute to the pathogenic nature of this bacterium, including the ability to tolerate the high concentrations of bile found in the gastrointestinal tract (GIT). The activity of bile salts is similar to detergents and may lead to membrane permeabilization and cell death. Modulation of outer membrane proteins (OMPs) is considered a crucial event to bile salts resistance. The primary objective of the current work was to identify B. fragilis proteins associated with the stress induced by high concentration of bile salts. The outer membrane of B. fragilis strain 638R was isolated after growth either in the presence of 2% conjugated bile salts or without bile salts. The membrane fractions were separated on SDS-PAGE and analyzed by ESI-Q/TOF tandem mass spectrometry. A total of 37 proteins were identified; among them nine were found to be expressed exclusively in the absence of bile salts whereas eight proteins were expressed only in the presence of bile salts. These proteins are related to cellular functions such as transport through membrane, nutrient uptake, and protein-protein interactions. This study demonstrates the alteration of OMPs composition in B. fragilis during bile salts stress resistance and adaptation to environmental changes. Proteomics of OMPs was also shown to be a useful approach in the identification of new targets for functional analyses. PMID:26948242

  8. 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.

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

    Science.gov (United States)

    Adamberg, Kaarel; Tomson, Katrin; Talve, Tiina; Pudova, Ksenia; Puurand, Marju; Visnapuu, Triinu; Alamäe, Tiina; Adamberg, Signe

    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 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. PMID:26629816

  10. Pyogenic arthritis of native joints due to Bacteroides fragilis: Case report and review of the literature.

    Science.gov (United States)

    Nolla, Joan M; Murillo, Oscar; Narvaez, Javier; Vaquero, Carmen Gómez; Lora-Tamayo, Jaime; Pedrero, Salvador; Cabo, Javier; Ariza, Javier

    2016-06-01

    Pyogenic arthritis of native joints due to Bacteroides fragilis seems to be an infrequent disease. We analyzed the cases diagnosed in a tertiary hospital during a 22-year period and reviewed the literature to summarize the experience with this infectious entity.In our institution, of 308 patients with pyogenic arthritis of native joints, B fragilis was the causative organism in 2 (0.6%) cases. A MEDLINE search (1981-2015) identified 19 additional cases.Of the 21 patients available for review (13 men and 8 women, with a mean age, of 54.4 ± 17 years), 19 (90%) presented a systemic predisposing factor for infection; the most common associated illness was rheumatoid arthritis (8 patients). Bacteremia was documented in 65% (13/20) of cases. In 5 patients (24%), 1 or more concomitant infectious process was found. Metronidazole was the most frequently used antibiotic. Surgical drainage was performed in 11 cases (52%). The overall mortality rate was 5%.Pyogenic arthritis of native joints due to B fragilis is an infrequent disease that mainly affects elderly patients with underlying medical illnesses and in whom bacteremia and the presence of a concomitant infectious process are frequent conditions. PMID:27336895

  11. 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.

  12. 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.

  13. Isolation, Detection, and Characterization of Enterotoxigenic Bacteroides fragilis in Clinical Samples

    Science.gov (United States)

    Fathi, Payam; Wu, Shaoguang

    2016-01-01

    Bacteroides fragilis is an extensively studied anaerobic bacterium comprising the normal flora of the human gut. B. fragilis is known to be one of the most commonly isolated species from clinical samples and has been shown to cause a wide range of pathologies in humans [1, 2]. As an opportunistic pathogen B. fragilis can cause abscess formation and bacteremia [2]. Additionally in its enterotoxigenic form, B. fragilis is a known cause of diarrheal illness, is associated with inflammatory bowel disease, and has been recently characterized in patients with colon cancer [3 - 5]. As research in the field of the gut microbiome continues to expand at an ever increasing rate due to advances in the availability of next generation sequencing and analysis tools it is important to outline various molecular methods that can be employed in quickly detecting and isolating relevant strains of B. fragilis. This review outlines methods that are routinely employed in the isolation and detection of B. fragilis, with an emphasis on characterizing enterotoxigenic B. fragilis (ETBF) strains.

  14. 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.

  15. 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.

  16. A novel strain of Bacteroides fragilis enhances phagocytosis and polarises M1 macrophages

    Science.gov (United States)

    Deng, Huimin; Li, Zhengchao; Tan, Yafang; Guo, Zhaobiao; Liu, Yangyang; Wang, Ye; Yuan, Yuan; Yang, Ruifu; Bi, Yujing; Bai, Yang; Zhi, Fachao

    2016-01-01

    Commensal Bacteroides fragilis possesses immune-regulatory characteristics. Consequently, it has been proposed as a potential novel probiotic because of its therapeutic effects on immune imbalance, mental disorders and inflammatory diseases. Macrophages play a central role in the immune response, developing either a classical-M1 or an alternative-M2 phenotype after stimulation with various signals. The interactions between macrophages and B. fragilis, however, remain to be defined. Here, a new isolate of B. fragilis, ZY-312, was shown to possess admirable properties, including tolerance to simulated gastric fluid, intestinal fluid and ox bile, and good safety (MOI = 100, 200) and adherent ability (MOI = 100) to LoVo cells. Isolate ZY-312 cell lysate promoted phagocytosis of fluorescent microspheres and pathogenic bacteria in bone marrow-derived macrophage (BMDM) cells. Gene expression of IL-12, iNOS and IL-1β in BMDM cells was increased after treatment with ZY-312, indicating the induction of M1 macrophages, consistent with enhanced secretion of NO. Cell surface expression of CD80 and CD86 was also increased. This study is the first to demonstrate that B. fragilis enhances the phagocytic functions of macrophages, polarising them to an M1 phenotype. Our findings provide insight into the close relationship between B. fragilis and the innate immune system. PMID:27381366

  17. Azide protection of bacteroides superoxide dismutases from inactivation by hydrogen peroxide

    International Nuclear Information System (INIS)

    The anaerobes Bacteroides fragilis, B. distasonis and B. thetaiotaomicron produce an iron-containing superoxide dismutase (FeSOD). These FeSODs are reversibly inhibited by 1 mM azide (NaN3) and are irreversibly inactivated upon incubation with hydrogen peroxide (H2O2). H2O2 inactivation of the enzyme likely depends on a Fenton type reaction with the production of hydroxyl radical (OH). Addition of NaN3 to the enzyme solution decreased the rate of inactivation by H2O2. After 20 minutes incubation of purified B. distasonis FeSOD with 2.5 mM H2O2, 61% of the initial enzymatic activity remained when 1 mM NaN3 was also present compared with 29% activity without NaN3. Similar results were seen with FeSOD from B. fragilis and B. thetaiotaomicron. Metal analyses of the native, peroxidized, and NaN3 protected samples are consistent with loss of Fe from the enzyme upon peroxidation, but retention of Fe and enzymatic activity in the NaN3 protected sample. Protection of FeSOD activity from H2O2 inactivation was dependent on NaN3 concentration. Anionic hydroxyl radical scavengers, such as urate and xanthine did not significantly protect the enzyme. The results are consistent with binding of azide to the active site either preventing entry of H2O2 or altering Fe redox potential, preventing OH production

  18. 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.

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

    International Nuclear Information System (INIS)

    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 45Ca 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)

  20. Metabolism of poly-β-hydroxybutyric acid in bacteroids of Rhizobium lupini in connection with nitrogen fixation and photosynthesis

    International Nuclear Information System (INIS)

    The darkening of lupin plants grown in a sand culture on a nitrogen-free medium at a stage of initial flowering led to a sharply decreased nitrogen fixation intensity which eventually ceased. Decreased intensity of nitrogen fixation in bacteroids was accompanied by an accumulation of poly-β-hydroxybutyric acid (PHB): in the course of 10-20 h (depending upon temperature) its content increased by 2.5-3.0 times. If, following darkening, the plants were once again exposed to light, an abrupt increase of nitrogen fixation intensity was observed and a simultaneous decrease of PHB content. It has been shown that lupin's exposure to light in 14CO2 atmosphere lasting 19 h resulted in the latter's incorporation into PHB, bacteroids and into the entire nodule; these processes developed almost in parallel. During the early period of vegetation growth prior to flowering, the PHB content of bacteroids decreased from 13 14 to 3.4% of dry weight, whereas the intensity of nitrogen fixation was raised. Concurrently increase of the activity of some enzymes connected with the PHB metabolism (aceto-acetyl-CoA-reductase, acetyl-CoA acetyl transferase PHB-depolymerase, (CoA-transferase, of 3-ketoacids) occured. The plants' subsequent ageing and reduction of nitrogen fixation intensity led to a noticeable increase of PHB content and a decrease of the above mentioned enzymes' activity. The specific activity of β-hydroxybutyric dehydrogenase involved with PHB catabolism was high and was maintained at a constant level throughout the entire vegetative period. (orig.)

  1. Effect of extracellular pH on growth and proton motive force of Bacteroides succinogenes, a cellulolytic ruminal bacterium.

    OpenAIRE

    Russell, J B

    1987-01-01

    The utilization of cellulose or cellobiose by Bacteroides succinogenes S85 was severely inhibited at pH values of less than 5.7. Since low pH inhibited the utilization of both cellobiose and cellulose, changes in cellulase activity could not explain the effect. At an extracellular pH of 6.9, the pH gradient (delta pH) across the cell membrane was only 0.07 U. As extracellular pH declined from 6.9 to 5.7, intracellular pH decreased to a smaller extent than extracellular pH and delta pH increas...

  2. Development of a Gene Inactivation System for Bacteroides forsythus: Construction and Characterization of a BspA Mutant

    OpenAIRE

    Honma, Kiyonobu; Kuramitsu, Howard K.; Genco, Robert J.; Sharma, Ashu

    2001-01-01

    Bacteroides forsythus is a gram-negative anaerobic bacterium associated with periodontitis. The bspA gene encoding a cell surface associated leucine-rich repeat protein (BspA) involved in adhesion to fibronectin and fibrinogen was recently cloned from this bacterium in our laboratory. We now describe the construction of a BspA-defective mutant of B. forsythus. This is the first report describing the generation of a specific gene knockout mutant of B. forsythus, and this procedure should be us...

  3. Development of a Gene Inactivation System for Bacteroides forsythus: Construction and Characterization of a BspA Mutant

    Science.gov (United States)

    Honma, Kiyonobu; Kuramitsu, Howard K.; Genco, Robert J.; Sharma, Ashu

    2001-01-01

    Bacteroides forsythus is a gram-negative anaerobic bacterium associated with periodontitis. The bspA gene encoding a cell surface associated leucine-rich repeat protein (BspA) involved in adhesion to fibronectin and fibrinogen was recently cloned from this bacterium in our laboratory. We now describe the construction of a BspA-defective mutant of B. forsythus. This is the first report describing the generation of a specific gene knockout mutant of B. forsythus, and this procedure should be useful in establishing the identity of virulence-associated factors in these organisms. PMID:11402017

  4. Comparison of the activity of imipenem and beta-lactams combined with sulbactam and clavulanic acid in beta-lactamase-producing strains of Bacteroides fragilis.

    Science.gov (United States)

    Martín, M A; Castillo, A M; Liébana, J; Marín, A; Alados, J C; Piédrola, G

    1991-01-01

    We compared the "in vitro" activity of imipenem with 14 beta-lactams, both alone and in combination with clavulanic acid, and sulbactam against 110 beta-lactamase-producing strains of Bacteroides fragilis. The following antibiotics were tested: amoxycillin, penicillin, mezlocillin, piperacillin, cephalothin, cephazolin, cefamandole, cefmetazole, cefonicid, cefoxitin, cefotaxime, ceftazidime, ceftizoxime, and ceftriaxone. In all cases, except those of cefoxitin and cefmetazole, these combinations showed a statistically significant increase in beta-lactam activity, which was, however, never higher than that of imipenem, the antibiotic which performed best against Bacteroides fragilis. PMID:1940333

  5. NAD- and NADP-dependent 7alpha-hydroxysteroid dehydrogenases from bacteroides fragilis.

    Science.gov (United States)

    Macdonald, I A; Williams, C N; Mahony, D E; Christie, W M

    1975-03-28

    Twenty strains of Bacteroides fragilis were screened for hydroxysteroid oxidoreductase activity in cell-free preparations. Eighteen strains were shown to contain NAD-dependent 7alpha-hydroxysteroid dehydrogenase. Sixteen of the strains containing the NAD-dependent enzyme also contained NADP-depedent 7alpha-hydroxysteroid dehydrogenase, but invariably in lesser amounts. A strain particulary rich in both 7alpha-hydroxysteroid dehydrogenase activities was selected for further study. Measurement of activity as a function of pH revealed a fairly sharp optimal activity range of 9.5--10.0 for the NAD-dependent enzyme and a broad flat optimal range of 7.0--9.0 for the NADP-dependent enzyme. Michaelis constants for trihydroxy-bile acids for the NAD-dependent enzyme were in the range of 0.32--0.34 mM, whereas dihydroxy-bile acids gave a Km of 0.1 mM. Thin-layer chromatography studies on the oxidation product of 3alpha, 7alpha-dihydroxy-5beta-cholanoic acid (chenodeoxycholic acid) by the dehydrogenase revealed a band corresponding to that of synthetic 3alpha-hydroxy, 7-keto-5beta-cholanoic acid. Similarly the oxidation product of chenodeoxycholic acid by both 7alpha-hydroxysteroid dehydrogenase and commercially available 3alpha-hy-droxysteroid dehydrogenase revealed a band corresponding to that of synthetic 3,7-diketo-5beta-cholanoic acid. Neither of these two oxidation products could be distinguished from those by the Escherichia coli dehydrogenase oxidation previously reported. Disc-gel electrophoresis of a cell-free lyophilized preparation indicated one active band for NAD-dependent activity of mobility similar to that for the NADP-dependent E. coli enzyme. The NADP-dependent dehydrogenase was unstable and rapidly lost activity after polyacylamide disc-gel electrophoresis, ultracentrifugation, freezing on refrigeration at 4 degrees C. No 3 alpha- or 12alpha-oriented oxidoreductase activity was demonstrated in any of the strains examined. PMID:236764

  6. Efficient and regioselective synthesis of globotriose by a novel α-galactosidase from Bacteroides fragilis.

    Science.gov (United States)

    Gong, Wei; Xu, Li; Gu, Guofeng; Lu, Lili; Xiao, Min

    2016-08-01

    Globotriose (Galα1-4Galβ1-4Glc) is an important cell surface epitope that acts as the receptor for Shiga-like toxins, and it is also the core structure of Globo H and SSEA4 that are tumor-associated glycans. Hence, the enzymatic synthesis of globotriose would be necessary for the development of carbohydrate-based therapeutics for bacterial infections and cancers. Here, a novel GH27 α-galactosidase gene (agaBf3S), a 1521-bp DNA encoding 506 amino acids with a calculated molecular mass of 57.7 kDa, from Bacteroides fragilis NCTC9343 was cloned and heterogeneously expressed in Escherichia coli. The recombinant enzyme AgaBf3S preferentially hydrolyzed p-nitrophenyl-α-D-galactopyranoside (pNPαGal) in all tested nitrophenyl glycosides. It showed maximum activity at pH 4.5 and 40 °C, and it was stable at pH 4.0-11.0 below 40 °C and metal-independent. The K m and k cat values for pNPαGal, melibiose, and globotriose were 1.27 mM and 172.97 S(-1), 62.76 mM and 17.74 S(-1), and 4.62 mM and 388.45 S(-1), respectively. AgaBf3S could transfer galactosyl residue from pNPαGal to lactose (Galβ1-4Glc) with high efficiency and strict α1-4 regioselectivity. The effects of initial substrate concentration, pH, temperature, and reaction time on transglycosylation reaction catalyzed by AgaBf3S were studied in detail. AgaBf3S could synthesize globotriose as a single transglycosylation product with a maximum yield of 32.4 % from 20 mM pNPαGal and 500 mM lactose (pH 4.5) at 40 °C for 30 min. This new one-enzyme one-step synthetic reaction is simple, fast, and low cost, which provides a promising alternative to the current synthetic methods for access to pharmaceutically important Galα1-4-linked oligosaccharides. PMID:27020280

  7. Pirin-like proteins are regulated by oxidative stress and iron in bacteroides fragilis and involved in the modulation of central energy metabolism and metronidazole susceptibility

    Science.gov (United States)

    Bacteroides fragilis is the most frequent anaerobe isolated from human infections. Clinical isolates of B. fragilis are among the highest aerotolerant anaerobic bacteria. The oxidative stress response (OSR) in B. fragilis induces an array of genes enabling them to survive prolonged oxygen exposure i...

  8. 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

  9. 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

    clearly separated the resistant and the susceptible population of B. fragilis group strains. In the case of cefoxitin only resistant population could be separated with an inhibition zone <17 mm, intermediate and susceptible isolates overlap. In conclusion, we suggest that disk diffusion can be an option...... 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...... with haemin and vitamin K1. Plates were incubated at 37 °C in an anaerobic atmosphere for 24 hours. The zone diameters were read at 100% inhibition. In case of discrepant results MICs were determined by gradient test and compared with the inhibition zones on the same plate. We found a good agreement...

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

    International Nuclear Information System (INIS)

    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

  11. Fluorescence studies with malate dehydrogenase from rhizobium japonicum 3I1B-143 bacteroids: a two-tryptophan containing protein

    Science.gov (United States)

    Ghiron, Camillo A.; Eftink, Maurice R.; Waters, James K.; Emerich, David W.

    1990-05-01

    A number of fluorescence studies, both of trp residues and bound NADH, have been reported for porcine MDH. The large number of trp residues (6) complicates the interpretation of some studies. To circumvent this we have performed studies with a two tryptophan (per subunit) MDH from Rhizobium japonicum 311B-143 bacteroids. We have performed phase/modulation fluorescence lifetime measurements, as a function of temperature and added quencher KI, in order to resolved the 1.3 ns (blue) and 6.6 ns (red) contributions from the two classes of trp residues. Anisotropy decay studies have also been performed. The binding of NADH dynamically quenches the fluorescence of both tip residues, but, unlike mammalian cytoplasmic and mitochondrial MDH, there is not a large enhancement in fluorescence of bound NADH upon forming a ternary complex with either tartronic acid or D-malonate.

  12. 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)

    Bradyrhizobium japonicum is a symbiotic nitrogen-fixing soil bacteria that induce root nodules formation in legume soybean (Glycine max.). Using 13C- and 31P-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)

  13. 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)

    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

  14. Effect of pH on tritium exchange and hydrogen production and uptake in free-living cells and in bacteroids of Bradyrhizobium japonicum

    International Nuclear Information System (INIS)

    Soybean nodule bacteroids and Bradyrhizobium japonicum free-living cells induced for H2-uptake hydrogenase, actively catalyze the evolution of H2 in a reaction highly dependent on the pH. The optimal pHs for the evolution and uptake reactions were 4.0 and 7.5-8.0, respectively. No differences were found between free-living cells and bacteroids with respect to hydrogen acceptor specificity, although absolute rates of H2 uptake were higher for free-living cells. Both types of cells were able to evolve hydrogen from reduced methyl viologen at low pH. These intact cells also catalyzed the exchange reaction between tritium and water in the absence of oxygen. The pH profile of the exchange activity showed two peaks at values near the optimal pHs for the evolution and uptake reactions

  15. Activities of New Antimicrobial Agents (Trovafloxacin, Moxifloxacin, Sanfetrinem, and Quinupristin-Dalfopristin) against Bacteroides fragilis Group: Comparison with the Activities of 14 Other Agents

    OpenAIRE

    Betriu, Carmen; Gómez, María; Palau, M. Luisa; Sánchez, Ana; Picazo, Juan J.

    1999-01-01

    The antimicrobial activities of trovafloxacin, moxifloxacin, sanfetrinem, quinupristin-dalfopristin, and 14 other antimicrobial agents against 218 Bacteroides fragilis group strains were determined. A group of 10 imipenem-resistant strains were also tested. Imipenem, meropenem, and sanfetrinem had the lowest MICs of all of the β-lactams. Quinupristin-dalfopristin inhibited all of the strains at 2 μg/ml. Overall, the MICs of trovafloxacin and moxifloxacin for 90% of the strains tested were 1 a...

  16. Antagonism exerted by an association of a Bacteroides thetaiotaomicron strain and a Fusobacterium necrogenes strain against Clostridium perfringens in gnotobiotic mice and in fecal suspensions incubated in vitro.

    OpenAIRE

    Yurdusev, N; Ladire, M; Ducluzeau, R.; Raibaud, P

    1989-01-01

    Antagonism between an association of Bacteroides thetaiotaomicron and Fusobacterium necrogenes strains and two strains of Clostridium perfringens was evidenced both in vivo in gnotobiotic mice and ex vivo in fecal suspensions incubated for 22 h at 37 degrees C. Several features of this antagonism were similar in and ex vivo. (i) An obligate and continuous synergy between B. thetaiotaomicron and F. necrogenes was required; (ii) the two C. perfringens strains did not respond to the same extent ...

  17. Distribution, Detection of Enterotoxigenic Strains and Antimicrobial Drug Susceptibility Patterns of Bacteroides Fragilis Group in Diarrheic and Non-Diarrheic Feces from Brazilian Infants

    OpenAIRE

    Débora Paula Ferreira; Vânia Lúcia Silva; Danielle Aparecida Guimarães; Cíntia Marques Coelho; Danielle Alves Gomes Zauli; Luiz de Macêdo Farias; Maria Auxiliadora Roque Carvalho; Claudio Galuppo Diniz

    2010-01-01

    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. Diarrhe...

  18. Comparison of the inoculum effect of cefoxitin and other cephalosporins and of beta-lactamase inhibitors and their penicillin-derived components on the Bacteroides fragilis group.

    OpenAIRE

    Goldstein, E J; Citron, D M; Cherubin, C E

    1991-01-01

    We compared the inoculum effects for 109 recent clinical isolates of the Bacteroides fragilis group of cefoxitin, cefotetan, ceftizoxime, ceftriaxone, and three beta-lactamase inhibitors (clavulanic acid, sulbactam, and tazobactam) and their penicillin-derived components. Bactericidal activity was assayed and morphologic changes were monitored for selected strains exhibiting a large inoculum effect. Ceftizoxime demonstrated the largest inoculum effect, followed by cefotetan and ceftriaxone. T...

  19. A recent fixation of cfiA genes in a monophyletic cluster of Bacteroides fragilis is correlated with the presence of multiple insertion elements.

    OpenAIRE

    Ruimy, R; Podglajen, I.; Breuil, J; Christen, R; Collatz, E.

    1996-01-01

    Small-subunit ribosomal DNA sequences of 16 strains of Bacteroides fragilis were determined and compared with previously published sequences. Three phylogenetic methods (the neighbor-joining, maximum-likelihood, and maximum-parsimony methods) as well as a bootstrap analysis were used to assess the robustness of each topology. All phylogenetic analyses demonstrated that the B. fragilis strains were clearly divided into two robust monophyletic units which corresponded to the cfiA-negative and c...

  20. Cloning, Expression, and Sequencing of a Cell Surface Antigen Containing a Leucine-Rich Repeat Motif from Bacteroides forsythus ATCC 43037

    OpenAIRE

    Sharma, Ashu; Sojar, Hakimuddin T.; Glurich, Ingrid; Honma, Kiyonobu; Kuramitsu, Howard K.; Genco, Robert J.

    1998-01-01

    Bacteroides forsythus is a recently recognized human periodontopathogen associated with advanced, as well as recurrent, periodontitis. However, very little is known about the mechanism of pathogenesis of this organism. The present study was undertaken to identify the surface molecules of this bacterium that may play roles in its adherence to oral tissues or triggering of a host immune response(s). The gene (bspA) encoding a cell surface-associated protein of B. forsythus with an apparent mole...

  1. A PCR Assay To Discriminate Human and Ruminant Feces on the Basis of Host Differences in Bacteroides-Prevotella Genes Encoding 16S rRNA

    OpenAIRE

    Bernhard, Anne E.; Field, Katharine G.

    2000-01-01

    Our purpose was to develop a rapid, inexpensive method of diagnosing the source of fecal pollution in water. In previous research, we identified Bacteroides-Prevotella ribosomal DNA (rDNA) PCR markers based on analysis. These markers length heterogeneity PCR and terminal restriction fragment length polymorphism distinguish cow from human feces. Here, we recovered 16S rDNA clones from natural waters that were close phylogenetic relatives of the markers. From the sequence data, we designed spec...

  2. Biochemical evidence that starch breakdown by Bacteroides thetaiotaomicron involves outer membrane starch-binding sites and periplasmic starch-degrading enzymes.

    OpenAIRE

    Anderson, K L; Salyers, A A

    1989-01-01

    Bacteroides thetaiotaomicron can utilize amylose, amylopectin, and pullulan as sole sources of carbon and energy. The enzymes that degrade these polysaccharides were found to be primarily cell associated rather than extracellular. Although some activity was detected in extracellular fluid, this appeared to be the result of cell lysis. The cell-associated amylase, amylopectinase, and pullulanase activities partitioned similarly to the periplasmic marker, acid phosphatase, when cells were expos...

  3. Expression of arsenic resistance genes in the obligate anaerobe Bacteroides vulgatus ATCC 8482, a gut microbiome bacterium.

    Science.gov (United States)

    Li, Jiaojiao; Mandal, Goutam; Rosen, Barry P

    2016-06-01

    The response of the obligate anaerobe Bacteroides vulgatus ATCC 8482, a common human gut microbiota, to arsenic was determined. B. vulgatus ATCC 8482 is highly resistant to pentavalent As(V) and methylarsenate (MAs(V)). It is somewhat more sensitive to trivalent inorganic As(III) but 100-fold more sensitive to methylarsenite (MAs(III)) than to As(III). B. vulgatus ATCC 8482 has eight continuous genes in its genome that we demonstrate form an arsenical-inducible transcriptional unit. The first gene of this ars operon, arsR, encodes a putative ArsR As(III)-responsive transcriptional repressor. The next three genes encode proteins of unknown function. The remaining genes, arsDABC, have well-characterized roles in detoxification of inorganic arsenic, but there are no known genes for MAs(III) resistance. Expression of each gene after exposure to trivalent and pentavalent inorganic and methylarsenicals was analyzed. MAs(III) was the most effective inducer. The arsD gene was the most highly expressed of the ars operon genes. These results demonstrate that this anaerobic microbiome bacterium has arsenic-responsive genes that confer resistance to inorganic arsenic and may be responsible for the organism's ability to maintain its prevalence in the gut following dietary exposure to inorganic arsenic. PMID:27040269

  4. Unraveling the substrate recognition mechanism and specificity of the unusual glycosyl hydrolase family 29 BT2192 from Bacteroides thetaiotaomicron.

    Science.gov (United States)

    Guillotin, Laure; Lafite, Pierre; Daniellou, Richard

    2014-03-11

    Glycosyl hydrolase (GH) family 29 (CAZy database) consists of retaining α-l-fucosidases. We have identified BT2192, a protein from Bacteroides thetaiotaomicron, as the first GH29 representative exhibiting both weak α-l-fucosidase and β-d-galactosidase activities. Determination and analysis of X-ray structures of BT2192 in complex with β-d-galactoside competitive inhibitors showed a new binding mode different from that of known GH29 enzymes. Three point mutations, specific to BT2192, prevent the canonical GH29 substrate α-l-fucose from binding efficiently to the fucosidase-like active site relative to other GH29 enzymes. β-d-Galactoside analogues bind and interact in a second pocket, which is not visible in other reported GH29 structures. Molecular simulations helped in the assessment of the flexibility of both substrates in their respective pocket. Hydrolysis of the fucosyl moiety from the putative natural substrates like 3-fucosyllactose or Lewis(X) antigen would be mainly due to the efficient interactions with the galactosyl moiety, in the second binding site, located more than 6-7 Å apart. PMID:24527659

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

    International Nuclear Information System (INIS)

    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

  6. 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

  7. 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.

  8. Pglyrp-Regulated Gut Microflora Prevotella falsenii, Parabacteroides distasonis and Bacteroides eggerthii Enhance and Alistipes finegoldii Attenuates Colitis in Mice.

    Directory of Open Access Journals (Sweden)

    Roman Dziarski

    Full Text Available Dysbiosis is a hallmark of inflammatory bowel disease (IBD, but it is unclear which specific intestinal bacteria predispose to and which protect from IBD and how they are regulated. Peptidoglycan recognition proteins (Pglyrps are antibacterial, participate in maintaining intestinal microflora, and modulate inflammatory responses. Mice deficient in any one of the four Pglyrp genes are more sensitive to dextran sulfate sodium (DSS-induced colitis, and stools from Pglyrp-deficient mice transferred to wild type (WT germ-free mice predispose them to much more severe colitis than stools from WT mice. However, the identities of these Pglyrp-regulated bacteria that predispose Pglyrp-deficient mice to colitis or protect WT mice from colitis are not known. Here we identified significant changes in β-diversity of stool bacteria in Pglyrp-deficient mice compared with WT mice. The most consistent changes in microbiome in all Pglyrp-deficient mice were in Bacteroidales, from which we selected four species, two with increased abundance (Prevotella falsenii and Parabacteroides distasonis and two with decreased abundance (Bacteroides eggerthii and Alistipes finegoldii. We then gavaged WT mice with stock type strains of these species to test the hypothesis that they predispose to or protect from DSS-induced colitis. P. falsenii, P. distasonis, and B. eggerthii all enhanced DSS-induced colitis in both WT mice with otherwise undisturbed intestinal microflora and in WT mice with antibiotic-depleted intestinal microflora. By contrast, A. finegoldii (which is the most abundant species in WT mice attenuated DSS-induced colitis both in WT mice with otherwise undisturbed intestinal microflora and in WT mice with antibiotic-depleted intestinal microflora, similar to the colitis protective effect of the entire normal microflora. These results identify P. falsenii, P. distasonis, and B. eggerthii as colitis-promoting species and A. finegoldii as colitis-protective species.

  9. Fermentable non-starch polysaccharides increases the abundance of Bacteroides-Prevotella-Porphyromonas in ileal microbial community of growing pigs.

    Science.gov (United States)

    Ivarsson, E; Roos, S; Liu, H Y; Lindberg, J E

    2014-11-01

    Most plant-origin fiber sources used in pig production contains a mixture of soluble and insoluble non-starch polysaccharides (NSP). The knowledge about effects of these sources of NSP on the gut microbiota and its fermentation products is still scarce. The aim of this study was to investigate effects of feeding diets with native sources of NSP on the ileal and fecal microbial composition and the dietary impact on the concentration of short-chain fatty acids (SCFA) and lactic acid. The experiment comprised four diets and four periods in a change-over design with seven post valve t-cecum cannulated growing pigs. The four diets were balanced to be similar in NSP content and included one of four fiber sources, two diets were rich in pectins, through inclusion of chicory forage (CFO) and sugar beet pulp, and two were rich in arabinoxylan, through inclusion of wheat bran (WB) and grass meal. The gut microbial composition was assessed with terminal restriction fragment (TRF) length polymorphism and the abundance of Lactobacillus spp., Enterobacteriaceae, Bacteroides-Prevotella-Porphyromonas and the β-xylosidase gene, xynB, were assessed with quantitative PCR. The gut microbiota did not cluster based on NSP structure (arabinoxylan or pectin) rather, the effect was to a high degree ingredient specific. In pigs fed diet CFO, three TRFs related to Prevotellaceae together consisted of more than 25% of the fecal microbiota, which is about 3 to 23 times higher (Pchicory pectin increased the acetic acid proportion in both ileal digesta and feces. PMID:25046106

  10. 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.

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

    International Nuclear Information System (INIS)

    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

  12. Degradation of Fructans and Production of Propionic Acid by Bacteroides thetaiotaomicron are Enhanced by the Shortage of Amino Acids.

    Science.gov (United States)

    Adamberg, Signe; Tomson, Katrin; Vija, Heiki; Puurand, Marju; Kabanova, Natalja; Visnapuu, Triinu; Jõgi, Eerik; Alamäe, Tiina; Adamberg, Kaarel

    2014-01-01

    Bacteroides thetaiotaomicron is commonly found in the human colon and stabilizes its ecosystem by 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 (degree of polymerization > 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

  13. 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 BACKGROUND: 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. METHODS: 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. RESULTS: 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. CONCLUSIONS: 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

  14. Bacteroides fragilis type VI secretion systems use novel effector and immunity proteins to antagonize human gut Bacteroidales species.

    Science.gov (United States)

    Chatzidaki-Livanis, Maria; Geva-Zatorsky, Naama; Comstock, Laurie E

    2016-03-29

    Type VI secretion systems (T6SSs) are multiprotein complexes best studied in Gram-negative pathogens where they have been shown to inhibit or kill prokaryotic or eukaryotic cells and are often important for virulence. We recently showed that T6SS loci are also widespread in symbiotic human gut bacteria of the order Bacteroidales, and that these T6SS loci segregate into three distinct genetic architectures (GA). GA1 and GA2 loci are present on conserved integrative conjugative elements (ICE) and are transferred and shared among diverse human gut Bacteroidales species. GA3 loci are not contained on conserved ICE and are confined toBacteroides fragilis Unlike GA1 and GA2 T6SS loci, most GA3 loci do not encode identifiable effector and immunity proteins. Here, we studied GA3 T6SSs and show that they antagonize most human gut Bacteroidales strains analyzed, except forB. fragilisstrains with the same T6SS locus. A combination of mutation analyses,trans-protection analyses, and in vitro competition assays, allowed us to identify novel effector and immunity proteins of GA3 loci. These proteins are not orthologous to known proteins, do not contain identified motifs, and most have numerous predicted transmembrane domains. Because the genes encoding effector and immunity proteins are contained in two variable regions of GA3 loci, GA3 T6SSs of the speciesB. fragilisare likely the source of numerous novel effector and immunity proteins. Importantly, we show that the GA3 T6SS of strain 638R is functional in the mammalian gut and provides a competitive advantage to this organism. PMID:26951680

  15. Detection of non-enterotoxigenic and enterotoxigenic Bacteroides fragilis in stool samples from children in São Paulo, Brazil Detecção de Bacteroides fragilis enterotoxigênicos e não enterotoxigênicos de amostras fecais de crianças em São Paulo, Brasil

    OpenAIRE

    Flávio Krzyzanowsky; Avila-Campos, Mario J.

    2003-01-01

    Non-enterotoxigenic bacteria of the Bacteroides fragilis group and enterotoxigenic B. fragilis were identified from children with and without aqueous acute diarrhea. In this study, 170 stool samples from 96 children with and 74 without diarrhea were analyzed. Enterotoxin production and the toxin gene detection were detected by cytotoxicity assay on HT-29/C1 cells and by PCR, respectively. B. fragilis species was prevalent in both groups and enterotoxigenic B. fragilis strains were isolated fr...

  16. Levofloxacin plus Metronidazole Administered Once Daily versus Moxifloxacin Monotherapy against a Mixed Infection of Escherichia coli and Bacteroides fragilis in an In Vitro Pharmacodynamic Model

    OpenAIRE

    Hermsen, Elizabeth D.; Hovde, Laurie B.; Sprandel, Kelly A.; Rodvold, Keith A.; Rotschafer, John C.

    2005-01-01

    Moxifloxacin has been suggested as an option for monotherapy of intra-abdominal infections. Recent data support the use of a once-daily metronidazole regimen. The purpose of this study was to investigate the activity of levofloxacin (750 mg every 24 h [q24h]) plus metronidazole (1,500 mg q24h) compared with that of moxifloxacin (400 mg q24h) monotherapy in a mixed-infection model. By using an in vitro pharmacodynamic model in duplicate, Escherichia coli and Bacteroides fragilis were exposed t...

  17. 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

  18. Diversity of Bacteroides fragilis Strains in Their Capacity To Recover Phages from Human and Animal Wastes and from Fecally Polluted Wastewater

    OpenAIRE

    Puig, Anna; Queralt, Nuria; Jofre, Juan; Araujo, Rosa

    1999-01-01

    Great differences in capability to detect bacteriophages from urban sewage of the area of Barcelona existed among 115 strains of Bacteroides fragilis. The capability of six of the strains to detect phages in a variety of feces and wastewater was studied. Strains HSP40 and RYC4023 detected similar numbers of phages in urban sewage and did not detect phages in animal feces. The other four strains detected phages in the feces of different animal species and in wastewater of both human and animal...

  19. [Tracing the Fecal Contamination Sources Based on Bacteroides 16S rRNA PCR- DGGE in Karst Groundwater: Taking Laolongdong Underground River System, Nanshan, Chongqing as an Example].

    Science.gov (United States)

    Zhang, Hong; Jiang, Yong-jun; Zhang, Yuan-zhu; Duan, Yi-fan; Lü, Xian-fu; He, Qiu-fang

    2016-05-15

    Microbial contamination in karst groundwater continually increases and tracing the source researches has become a hot topic for international researchers. In this study, Laolongdong underground river at Nanshan, Chongqing was chosen as an example to adopt filter membrane methods to monitor the fecal microbial contaminations including the total bacterial concentration (TB), the total E. coli concentration (TE), the total fecal coliform (FC) and the total fecal Streptocoocci (FS). Bacteriodes was used as an indicator and PCR-DGGE analysis was used to trace fecal contamination sources in karst groundwater. The results suggested that groundwater in this area was seriously polluted by microbes from feces. The concentrations of microbial parameters exceeded limited levels greatly and the total bacterial amounts ranged 10-2.9 x 10⁷ CFU · mL⁻¹, the concentrations of E. coli were between 4.3-4.0 x 10⁵ CFU · mL⁻¹, the max concentration of FC was 1.1 x 10⁶ CFU · (100 mL)⁻¹ and the max concentration of FS was 1.1 x 10⁵ CFU · (100 mL)⁻¹. The FC/FS ratios were mostly over 2 which suggested that the main fecal source in groundwater was human feces. In addition, PCR-DGGE contrastive analysis of Bacteroides communities showed that the similarities between groundwater samples and human feces were in range of 7. 1% -69. 1% , and the similarity of the groundwater sample from Laolongdong underground river outlet was 69.1% . Bacteroides community similarities between groundwater samples and swine feces were in range of 1.1%-53.4%, and the similarity of Laolongdong underground river outlet was merely 1.5%. The similarity data implied that groundwater contamination resulted mainly from human feces, swine feces contamination composed part of animals' fecal contamination, and other animals' feces participated too. Furthermore, sequencing results of PCR-DGGE products revealed that most Bacteroides in groundwater originated from human intestinal tract and human feces

  20. Frequent occurrence of the human-specific Bacteroides fecal marker at an open coast marine beach: relationship to waves, tides and traditional indicators.

    Science.gov (United States)

    Santoro, Alyson E; Boehm, Alexandria B

    2007-08-01

    Molecular genetic markers, such as those from fecal Bacteroides microorganisms, can link microbial pollution with its source, and have been used successfully in studies of sheltered aquatic environments. Their applicability to wave-driven, open coast environments has not been tested. We assessed the contribution of a tidal outlet to surf zone water quality in coastal Orange County, California, USA by measuring three traditional culture-based fecal indicator bacteria (FIB) as well as the human-specific Bacteroides molecular marker (HF marker) at four shoreline locations. We found that total and fecal coliform levels were higher during low tides than high tides at two of the four stations, and that this effect was strongest at the mouth of the tidal lagoon and decayed with distance from the outlet. The HF marker was detected in 23% and 47% of samples from the tidal outlet and 26% and 41% of samples from an adjacent recreational beach in 2005 and 2006 respectively. Surprisingly, the station farthest from the tidal outlet had the highest occurrence of the HF marker. We found no relationship between FIB abundance and occurrence of the HF marker for individual samples, but that when the data were considered together by year, higher FIB abundance was correlated with a higher incidence of the HF marker. DNA sequences of the HF marker recovered from this site were > 99% similar to those recovered from other states and countries, suggesting low global diversity of this marker. These data provide strong support for the idea that multiple time points and physical conditions should be considered when assessing coastal water quality. PMID:17635548

  1. Independent and Combined Effects of Lactitol, Polydextrose, and Bacteroides thetaiotaomicron on Postprandial Metabolism and Body Weight in Rats Fed a High-Fat Diet

    Science.gov (United States)

    Olli, Kaisa; Saarinen, Markku T.; Forssten, Sofia D.; Madetoja, Mari; Herzig, Karl-Heinz; Tiihonen, Kirsti

    2016-01-01

    Obesity is related to the consumption of energy-dense foods in addition to changes in the microbiome where a higher abundance of gut Bacteroidetes can be found in lean subjects or after weight loss. Lactitol, a sweet-tasting sugar alcohol, is a common sugar-replacement in foods. Polydextrose (PDX), a highly branched glucose polymer, is known to reduce energy intake. Here, we test if the combined effects of lactitol or PDX in combination with Bacteroides species will have a beneficial metabolic response in rats fed a high-fat (HF) diet. A total of 175 male Wistar rats were fed either a LF or HF diet. Bacteroides thetaiotaomicron (1010 bacteria/animal/day) was orally administered with or without lactitol (1.6−2 g/animal/day) or PDX (2 g/animal/day) for 8 days. Postprandial blood samples, cecal digesta, and feces were collected on the last day. Measurements included: body weight, feed consumption, cecal short-chain fatty acids, fecal dry matter and heat value, blood glucose, insulin, triglyceride, and satiety hormone concentrations. Lactitol and PDX decreased the mean body weight when administered with B. thetaiotaomicron or when lactitol was administered alone. Levels of postprandial plasma triglycerides declined with lactitol and PDX when administered with B. thetaiotaomicron. For intestinal hormone release, lactitol – alone or with B. thetaiotaomicron – increased the release of gastrointestinal peptide tyrosine tyrosine (PYY) as well as the area under the curve (AUC) measured for PYY (0–8 h). In addition, levels of insulin AUC (0–8 h) decreased in the lactitol and PDX-supplemented groups. Lactitol and PDX may both provide additional means to regulate postprandial metabolism and weight management, whereas the addition of B. thetaiotaomicron in the tested doses had only minor effects on the measured parameters.

  2. 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. PMID:25540839

  3. Crystallization and preliminary X-ray crystallographic analysis of the tetracycline-degrading monooxygenase TetX2 from Bacteroides thetaiotaomicron

    International Nuclear Information System (INIS)

    Crystallization and preliminary X-ray crystallographic analysis of the tetracycline-degrading monooxygenase TetX2 from B. thetaiotaomicron are reported. The flavin-dependent monooxygenase TetX2 from Bacteroides thetaiotaomicron confers resistance against tetracyclines in aerobically grown Escherichia coli. TetX2 modifies several tetracycline antibiotics by regioselective hydroxylation of the substrates to 11a-hydroxy-tetracyclines. X-ray diffraction data were collected from a native TetX2 crystal and a TetX2 crystal with incorporated selenomethionine to resolutions of 2.5 and 3.0 Å, respectively. The native crystal belonged to the triclinic space group P1, with unit-cell parameters a = 68.55, b = 80.88, c = 87.53 Å, α = 111.09, β = 98.98, γ = 93.38°, whereas the selenomethionine-labelled TetX2 crystal belonged to the monoclinic space group P21, with unit-cell parameters a = 87.34, b = 68.66, c = 152.48 Å, β = 101.08°

  4. Acylhomoserine lactone production and degradation by the fish pathogen Tenacibaculum maritimum, a member of the Cytophaga-Flavobacterium-Bacteroides (CFB) group.

    Science.gov (United States)

    Romero, Manuel; Avendaño-Herrera, Rubén; Magariños, Beatriz; Cámara, Miguel; Otero, Ana

    2010-03-01

    Tenacibaculum maritimum (formerly Flexibacter maritimus) is a filamentous, biofilm-forming member of the Cytophaga-Flavobacterium-Bacteroides group (or Bacteroidetes), which causes the widely distributed marine fish disease tenacibaculosis. A search for N-acylhomoserine lactones (AHLs) quorum-sensing (QS) signals in the culture media of nine representative strains of this species using different biosensor strains revealed the presence of short-type AHL activity in all of them. N-butyryl-L-homoserine lactone (C4-HSL) was identified in T. maritimum NCIMB2154(T) by LC-MS. A degradation activity for long-acyl AHLs (C10-HSL) was subsequently demonstrated in T. maritimum NCIMB2154(T). The acidification of the culture medium after degradation did not allow the recovery of C10-HSL, which indicates a possible acylase-type degradation activity. Even though the physiological processes under the control of AHL-mediated QS in T. maritimum need to be further characterized, this discovery extends the paradigm of AHL-mediated QS signalling beyond the Proteobacteria and reinforces its ecological significance. PMID:20377642

  5. Reduced Carbon Availability to Bacteroids and Elevated Ureides in Nodules, But Not in Shoots, Are Involved in the Nitrogen Fixation Response to Early Drought in Soybean1[OA

    Science.gov (United States)

    Ladrera, Rubén; Marino, Daniel; Larrainzar, Estíbaliz; González, Esther M.; Arrese-Igor, Cesar

    2007-01-01

    Nitrogen fixation (NF) in soybean (Glycine max L. Merr.) is highly sensitive to soil drying. This sensitivity has been related to an accumulation of nitrogen compounds, either in shoots or in nodules, and a nodular carbon flux shortage under drought. To assess the relative importance of carbon and nitrogen status on NF regulation, the responses to the early stages of drought were monitored with two soybean cultivars with known contrasting tolerance to drought. In the sensitive cultivar (‘Biloxi’), NF inhibition occurred earlier and was more dramatic than in the tolerant cultivar (‘Jackson’). The carbon flux to bacteroids was also more affected in ‘Biloxi’ than in ‘Jackson’, due to an earlier inhibition of sucrose synthase activity and a larger decrease of malate concentration in the former. Drought provoked ureide accumulation in nodules of both cultivars, but this accumulation was higher and occurred earlier in ‘Biloxi’. However, at this early stage of drought, there was no accumulation of ureides in the leaves of either cultivar. These results indicate that a combination of both reduced carbon flux and nitrogen accumulation in nodules, but not in shoots, is involved in the inhibition of NF in soybean under early drought. PMID:17720761

  6. 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.

  7. Distribution, detection of enterotoxigenic strains and antimicrobial drug susceptibility patterns of bacteroides fragilis group in diarrheic and non-diarrheic feces from brazilian infants.

    Science.gov (United States)

    Ferreira, Débora Paula; Silva, Vânia Lúcia; Guimarães, Danielle Aparecida; Coelho, Cíntia Marques; Zauli, Danielle Alves Gomes; Farias, Luiz Macêdo; Carvalho, Maria Auxiliadora Roque; Diniz, Claudio Galuppo

    2010-07-01

    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. PMID:24031535

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

    Directory of Open Access Journals (Sweden)

    EFSA Panel on Dietetic Products, Nutrition and Allergies (NDA

    2015-01-01

    Full Text Available 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 of vitamins B2 and B12 and furosine in heat-treated fermented milk products does not give rise to concerns regarding disadvantageous nutritional effects. The Panel considers that the microbiological data provided do not give rise to safety concerns. The Panel also notes that a pilot study and a RCT over six weeks with 140 volunteers receiving daily doses of a spray-dried heat-treated fermented milk product containing intakes of up to 1 ´ 1012 inactivated bacterial cells of B. xylanisolvens DSM 23964 were provided. No clinical effects related to the treatment were observed in the two studies. Although no information has been provided to conclude on the risk of allergic reactions caused by the NF, the Panel considers that it is unlikely that its allergenic potential is dissimilar to that of other fermented dairy products. The Panel concludes that the NF ‘heat-treated milk products fermented with B. xylanisolvens DSM 23964’ is safe for the proposed uses and at the proposed use levels.

  9. 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

  10. 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. PMID:24459149

  11. Cloning, Expression, and Sequencing of a Cell Surface Antigen Containing a Leucine-Rich Repeat Motif from Bacteroides forsythus ATCC 43037

    Science.gov (United States)

    Sharma, Ashu; Sojar, Hakimuddin T.; Glurich, Ingrid; Honma, Kiyonobu; Kuramitsu, Howard K.; Genco, Robert J.

    1998-01-01

    Bacteroides forsythus is a recently recognized human periodontopathogen associated with advanced, as well as recurrent, periodontitis. However, very little is known about the mechanism of pathogenesis of this organism. The present study was undertaken to identify the surface molecules of this bacterium that may play roles in its adherence to oral tissues or triggering of a host immune response(s). The gene (bspA) encoding a cell surface-associated protein of B. forsythus with an apparent molecular mass of 98 kDa was isolated by immunoscreening of a B. forsythus gene library constructed in a lambda ZAP II vector. The encoded 98-kDa protein (BspA) contains 14 complete repeats of 23 amino acid residues that show partial homology to leucine-rich repeat motifs. A recombinant protein containing the repeat region was expressed in Escherichia coli, purified, and utilized for antibody production, as well as in vitro binding studies. The purified recombinant protein bound strongly to fibronectin and fibrinogen in a dose-dependent manner and further inhibited the binding of B. forsythus cells to these extracellular matrix (ECM) components. In addition, adult patients with B. forsythus-associated periodontitis expressed specific antibodies against the BspA protein. We report here the cloning and expression of an immunogenic cell surface-associated protein (BspA) of B. forsythus and speculate that it mediates the binding of bacteria to ECM components and clotting factors (fibronectin and fibrinogen, respectively), which may be important in the colonization of the oral cavity by this bacterium and is also a target for the host immune response. PMID:9826345

  12. Improved Multiplex PCR Using Conserved and Species-Specific 16S rRNA Gene Primers for Simultaneous Detection of Actinobacillus actinomycetemcomitans, Bacteroides forsythus, and Porphyromonas gingivalis

    Science.gov (United States)

    Tran, Simon Dangtuan; Rudney, Joel D.

    1999-01-01

    Among putative periodontal pathogens, Actinobacillus actinomycetemcomitans, Bacteroides forsythus, and Porphyromonas gingivalis are most convincingly implicated as etiological agents in periodontitis. Therefore, techniques for detection of those three species would be of value. We previously published a description of a multiplex PCR that detects A. actinomycetemcomitans and P. gingivalis. The present paper presents an improvement on that technique, which now allows more sensitive detection of all three periodontal pathogens. Sensitivity was determined by testing serial dilutions of A. actinomycetemcomitans, B. forsythus, and P. gingivalis cells. Primer specificity was tested against (i) all gene sequences from the GenBank-EMBL database, (ii) six A. actinomycetemcomitans, one B. forsythus, and four P. gingivalis strains, (iii) eight different species of oral bacteria, and (iv) supra- and subgingival plaque samples from 20 healthy subjects and subgingival plaque samples from 10 patients with periodontitis. The multiplex PCR had a detection limit of 10 A. actinomycetemcomitans, 10 P. gingivalis, and 100 B. forsythus cells. Specificity was confirmed by the fact that (i) none of our forward primers were homologous to the 16S rRNA genes of other oral species, (ii) amplicons of predicted size were detected for all A. actinomycetemcomitans, B. forsythus, and P. gingivalis strains tested, and (iii) no amplicons were detected for the eight other bacterial species. A. actinomycetemcomitans, B. forsythus, and P. gingivalis were detected in 6 of 20, 1 of 20, and 11 of 20 of supragingival plaque samples, respectively, and 4 of 20, 7 of 20, and 13 of 20 of subgingival plaque samples, respectively, from periodontally healthy subjects. Among patients with periodontitis, the organisms were detected in 7 of 10, 10 of 10, and 7 of 10 samples, respectively. The simultaneous detection of three periodontal pathogens is an advantage of this technique over conventional PCR assays. PMID

  13. 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

  14. Structure of Bacteroides thetaiotaomicron BT2081 at 2.05 Å resolution: the first structural representative of a new protein family that may play a role in carbohydrate metabolism

    International Nuclear Information System (INIS)

    The crystal structure of BT2081 from B. thetaiotaomicron reveals a two-domain protein with a putative carbohydrate-binding site in the C-terminal domain. BT2081 from Bacteroides thetaiotaomicron (GenBank accession code NP-810994.1) is a member of a novel protein family consisting of over 160 members, most of which are found in the different classes of Bacteroidetes. Genome-context analysis lends support to the involvement of this family in carbohydrate metabolism, which plays a key role in B. thetaiotaomicron as a predominant bacterial symbiont in the human distal gut microbiome. The crystal structure of BT2081 at 2.05 Å resolution represents the first structure from this new protein family. BT2081 consists of an N-terminal domain, which adopts a β-sandwich immunoglobulin-like fold, and a larger C-terminal domain with a β-sandwich jelly-roll fold. Structural analyses reveal that both domains are similar to those found in various carbohydrate-active enzymes. The C-terminal β-jelly-roll domain contains a potential carbohydrate-binding site that is highly conserved among BT2081 homologs and is situated in the same location as the carbohydrate-binding sites that are found in structurally similar glycoside hydrolases (GHs). However, in BT2081 this site is partially occluded by surrounding loops, which results in a deep solvent-accessible pocket rather than a shallower solvent-exposed cleft

  15. Polaribacter gen. nov., with three new species, P. irgensii sp. nov., P. franzmannii sp. nov. and P. filamentus sp. nov., gas vacuolate polar marine bacteria of the Cytophaga-Flavobacterium-Bacteroides group and reclassification of 'Flectobacillus glomeratus' as Polaribacter glomeratus comb. nov

    Science.gov (United States)

    Gosink, J. J.; Woese, C. R.; Staley, J. T.

    1998-01-01

    Several psychrophilic, gas vacuolate strains of the Cytophage-Flavobacterium-Bacteroides (CFB) phylogenetic group were isolated from sea ice and water from the Arctic and the Antarctic. The closest taxonomically defined species by 16S rRNA sequence analysis is 'Flectobacillus glomeratus'. However, 'Flc. glomeratus' is phylogenetically distant from the Flectobacillus type species, Flc. major. On the basis of phenotypic, genotypic and 16S rRNA sequence analyses we propose a new genus, Polaribacter, with three new species, Polaribacter irgensii strain 23-P (ATCC 700398), Polaribacter franzmannii strain 301 (ATCC 700399) and Polaribacter filamentus strain 215 (ATCC 700397). P. filamentus is the type species of the genus. None of these species exhibits a cosmopolitan or bipolar distribution. This is the first taxonomic description of gas vacuolate bacteria in the CFB group. Additionally, we propose that 'Flc. glomeratus' be reclassified to the genus Polaribacter as P. glomeratus, comb. nov.

  16. Hematogenous Long Bone Osteomyelitis by Prevotella (Bacteroides) Melaninogenicus

    OpenAIRE

    Karabinas, Panagiotis K; Stergios, Evangelopoulos Dimitrios; Athanasopoulou, Marina G; Vlamis, John

    2010-01-01

    Anaerobic infections are difficult to recognize and may lead to life threatening complications. We present the case of an acute Prevotella hematogenous infection of the humerus in a previously healthy adult patient, treated with a two-stage surgical treatment, emphasizing on the importance of the radical surgical debridement and the selection of the appropriate antimicrobial agents. To our knowledge, such an acute hematogenous infection has not been previously reported in the literature. Keyw...

  17. Xylan degradation by the anaerobic bacterium Bacteroides xylanolyticus.

    OpenAIRE

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

    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 the plant polymers can be conserved in fermentation products. The valorization of agricultural waste plant materials can consist of low and high technological processes. These include the production of biog...

  18. 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.

  19. Porphyromonas gingivalis, Bacteroides forsythus and other putative periodontal pathogens in subjects with and without periodontal destruction

    NARCIS (Netherlands)

    van Winkelhoff, AJ; Loos, BG; van der Reijden, WA; van der Velden, U

    2002-01-01

    Background and aims: Bacteria play an essential role in the pathogenesis of destructive periodontal disease. It has been suggested that not all bacteria associated with periodontitis may be normal inhabitants of a periodontally healthy dentition. In particular, Porphyromonas gingivalis and Actinobac

  20. Unraveling the pectinolytic function of Bacteroides xylanisolvens using a RNA-seq approach and mutagenesis

    OpenAIRE

    Despres, Jordane; Forano, Evelyne; Lepercq, Pascale; Comtet-Marre, Sophie; Jubelin, Grégory; Yeoman, Carl J.; Miller, Margret E. Berg; Fields, Christopher J.; Terrapon, Nicolas; Le Bourvellec, Carine; Renard, Catherine; Henrissat, Bernard; White, Bryan A

    2016-01-01

    Background Diet and particularly dietary fibres have an impact on the gut microbiome and play an important role in human health and disease. Pectin is a highly consumed dietary fibre found in fruits and vegetables and is also a widely used additive in the food industry. Yet there is no information on the effect of pectin on the human gut microbiome. Likewise, little is known on gut pectinolytic bacteria and their enzyme systems. This study was undertaken to investigate the mechanisms of pecti...

  1. Bacteroidal Diseases of Larval Honey Bee%蜜蜂细菌性幼虫病

    Institute of Scientific and Technical Information of China (English)

    黄文诚

    2004-01-01

    蜜蜂细菌性幼虫病主要是美洲幼虫腐臭病(简称美腐病)和欧洲幼虫腐臭病(简称欧腐病),此外还有一种称为粉状鳞片病的幼虫病,很少发生,对它的研究了解不多。

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

    OpenAIRE

    Adamberg, Kaarel; Tomson, Katrin; Talve, Tiina; Pudova, Ksenia; Puurand, Marju; Visnapuu, Triinu; Alamäe, Tiina; Adamberg, Signe

    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, change...

  3. 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...

  4. Bacteroides oralisのヒアルロニダーぜの精製とその性状

    OpenAIRE

    柴田, 幸永; 志村, 隆二; 藤村, 節夫; 中村, 武

    1988-01-01

    From a culture supernatant of B. oralis ATCC 33269, hyaluronidase was purified to homogeneity by ammonium sulfate precipitation, DEAE-cellulose column chromatography, gel filtration on Sephacryl S-300, and hydroxylapatite column chromatography. Specific activity increased 12,000 fold and recovery was 5.8% The molecular weight was determined to be 75,000 by gel filtration, and the isoelectric point was 7.6. The optimum pH for the activity was 5.5. The purified hyaluronidase degraded hyaluronic...

  5. The genes for three xylan-degrading activities from Bacteroides ovatus are clustered in a 3.8-kilobase region.

    OpenAIRE

    Whitehead, T. R.; Hespell, R B

    1990-01-01

    Genes coding for three xylan-degrading activities, xylanase, xylosidase, and arabinosidase, were simultaneously cloned from the colonic anaerobic organism Bacteriodes ovatus. The genes for the three enzymes were located on a 3.8-kilobase EcoRI genomic insert and were cloned by using plasmid pUC18. All three activities were expressed in Escherichia coli JM83, and all were cell associated. Expression of the xylanase gene was independent from expression of the xylosidase and arabinosidase genes,...

  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

    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...... vitamins B2 and B12 and furosine in heat-treated fermented milk products does not give rise to concerns regarding disadvantageous nutritional effects. The Panel considers that the microbiological data provided do not give rise to safety concerns. The Panel also notes that a pilot study and a RCT over six...... weeks with 140 volunteers receiving daily doses of a spray-dried heat-treated fermented milk product containing intakes of up to 1 ´ 1012 inactivated bacterial cells of B. xylanisolvens DSM 23964 were provided. No clinical effects related to the treatment were observed in the two studies. Although no...

  7. 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...

  8. Rhizobium nodM and nodN genes are common nod genes: nodM encodes functions for efficiency of nod signal production and bacteroid maturation.

    OpenAIRE

    Baev, N; Schultze, M; Barlier, I; Ha, D C; Virelizier, H.; Kondorosi, E.; Kondorosi, A

    1992-01-01

    Earlier, we showed that Rhizobium meliloti nodM codes for glucosamine synthase and that nodM and nodN mutants produce strongly reduced root hair deformation activity and display delayed nodulation of Medicago sativa (Baev et al., Mol. Gen. Genet. 228:113-124, 1991). Here, we demonstrate that nodM and nodN genes from Rhizobium leguminosarum biovar viciae restore the root hair deformation activity of exudates of the corresponding R. meliloti mutant strains. Partial restoration of the nodulation...

  9. 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 ...

  10. Normal luminal bacteria, especially Bacteroides species, mediate chronic colitis, gastritis, and arthritis in HLA-B27/human beta2 microglobulin transgenic rats.

    OpenAIRE

    Rath, H C; Herfarth, H H; Ikeda, J S; Grenther, W B; Hamm, T E; Balish, E; Taurog, J D; Hammer, R. E.; Wilson, K H; Sartor, R B

    1996-01-01

    Genetic and environmental factors are important in the pathogenesis of clinical and experimental chronic intestinal inflammation. We investigated the influence of normal luminal bacteria and several groups of selected bacterial strains on spontaneous gastrointestinal and systemic inflammation in HLA-B27 transgenic rats. Rats maintained germfree for 3-9 mo were compared with littermates conventionalized with specific pathogen-free bacteria. Subsequently, germfree transgenic rats were colonized...

  11. 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

    ≤ 0.05) compared with cells without bacteria added. The alteration in cellular GPR120 mRNA was observed with bacteria categorized as either probiotics or bacteria capable of inducing an anti-inflammatory effect. The beneficial effect of these bacteria may very well be mediated by regulation of GPR120...

  12. Identificación del origen de la contaminación fecal en aguas con Bifidobacterium spp. y/o Bacteroides spp. específicas de huéspedes

    OpenAIRE

    Gómez Doñate, Marta

    2014-01-01

    El agua es un recurso renovable y fundamental para el sustento y desarrollo de la vida en el planeta. Debido al crecimiento de la población humana junto con la expansión de la actividad industrial, la agricultura y ganadería intensivas y el cambio climático han provocado un gran deterioro en la calidad del agua. La contaminación de origen fecal es una de las fuentes más relevantes de la polución del agua, ya que puede comportar la presencia de microrganismos patógenos, los cuales implican un ...

  13. Cloning of a Chryseobacterium (Flavobacterium) meningosepticum Chromosomal Gene (blaACME) Encoding an Extended-Spectrum Class A β-Lactamase Related to the Bacteroides Cephalosporinases and the VEB-1 and PER β-Lactamases

    OpenAIRE

    Rossolini, Gian Maria; Franceschini, Nicola; Lauretti, Laura; Caravelli, Berardo; Riccio, Maria Letizia; Galleni, Moreno; Frère, Jean-Marie; Amicosante, Gianfranco

    1999-01-01

    In addition to the BlaB metallo-β-lactamase, Chryseobacterium (Flavobacterium) meningosepticum CCUG 4310 (NCTC 10585) constitutively produces a 31-kDa active-site serine β-lactamase, named CME-1, with an alkaline isoelectric pH. The blaACME gene that encodes the latter enzyme was isolated from a genomic library constructed in the Escherichia coli plasmid vector pACYC184 by screening for cefuroxime-resistant clones. Sequence analysis revealed that the CME-1 enzyme is a new class A β-lactamase ...

  14. Dicty_cDB: SFF774 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available 89 |AF280689.1 Bacteroides fragilis isolate BFR 2393 glutamine synthetase (glnA) gene, partial cds. 56 3e-04... 2 AF280688 |AF280688.1 Bacteroides fragilis isolate Tal2480 glutamine synthetase (glnA) gene, partial cds. ...56 3e-04 2 AF280643 |AF280643.1 Bacteroides fragilis isolate BFR3392 glutamine sy...nthetase (glnA) gene, partial cds. 56 3e-04 2 AF280679 |AF280679.1 Bacteroides fragilis isolate 1297 glutamin...e synthetase (glnA) gene, partial cds. 56 3e-04 2 AF280641 |AF280641.1 Bacteroides fragilis isolate Tal3636 glutamin

  15. Detection of Genetic Markers of Fecal Indicator Bacteria in Lake Michigan and Determination of Their Relationship to Escherichia coli Densities Using Standard Microbiological Methods

    OpenAIRE

    Bower, Patricia A.; Scopel, Caitlin O.; Jensen, Erika T.; Depas, Morgan M.; McLellan, Sandra L

    2005-01-01

    Lake Michigan surface waters impacted by fecal pollution were assessed to determine the occurrence of genetic markers for Bacteroides and Escherichia coli. Initial experiments with sewage treatment plant influent demonstrated that total Bacteroides spp. could be detected by PCR in a 25- to 125-fold-higher dilution series than E. coli and human-specific Bacteroides spp., which were both found in similar dilution ranges. The limit of detection for the human-specific genetic marker ranged from 0...

  16. Dicty_cDB: Contig-U13065-1 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available :none) Salmonella enterica subsp. ente... 50 5e-05 CR626927_476( CR626927 |pid:none) Bacteroides fragi...ium chrysogenum Wisconsi... 54 5e-06 AP006841_1248( AP006841 |pid:none) Bacteroides fragilis YC...:none) Ostreococcus lucimarinus CCE9901... 53 1e-05 AM902716_720( AM902716 |pid:none) Bordetella petrii stra...veticus DPC 457... 50 5e-05 CR626927_1013( CR626927 |pid:none) Bacteroides fragilis NCTC 9343,... 50... avium 197N complete ... 50 5e-05 AP006841_1145( AP006841 |pid:none) Bacteroides fragilis YCH46 DNA

  17. Dicty_cDB: Contig-U16292-1 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available :none) Bacteroides fragilis NCTC 9343,... 62 2e-19 (Q8A624) RecName: Full=6-phosphofructokin...:none) Bacteroides fragilis YCH46 DNA,... 62 2e-19 CR626927_3444( CR626927 |pid...alenii PYR-1... 47 7e-11 CR626927_174( CR626927 |pid:none) Bacteroides fragilis NCTC 9343, ... 49 7e-11 AP006841_217( AP006841 |pid...:none) Bacteroides fragilis YCH46 DNA, ... 49 7e-11 CP000820_1801( CP000820 |pid:none) Fra... DSM 6724,... 64 2e-18 CU207366_1625( CU207366 |pid:none) Gramella forsetii KT080

  18. Dicty_cDB: Contig-U10823-1 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available enterica subsp. enteri... 80 2e-13 CR626927_476( CR626927 |pid:none) Bacteroides fragilis NCTC 9343, ... 7...4e-13 AP006841_551( AP006841 |pid:none) Bacteroides fragilis YCH46 DNA, ... 79 4e-13 BA000023_2698( BA000023 |pid...:none) Saccharopolyspora erythraea NRR... 70 2e-10 AP006841_1248( AP006841 |pid:none) Bacteroides fragi...7 2e-09 AM902716_720( AM902716 |pid:none) Bordetella petrii strain DSM 128... 67 ...tum walsbyi DSM 16790 ... 62 9e-08 CR626927_1013( CR626927 |pid:none) Bacteroides fragilis NCTC 9343,...

  19. NCBI nr-aa BLAST: CBRC-GACU-23-0143 [SEVENS

    Lifescience Database Archive (English)

    Full Text Available CBRC-GACU-23-0143 ref|YP_001297499.1| two-component system sensor histidine kinase/response regu ... lator, hybrid ... [Bacteroides vulgatus ATCC 8482] gb|ABR37877.1| tw ... system sensor histidine kinase/response regulator, hybrid ... [Bacteroides vulgatus ATCC 8482] YP_001297499.1 9. ...

  20. Gene : CBRC-GACU-23-0143 [SEVENS

    Lifescience Database Archive (English)

    Full Text Available CBRC-GACU-23-0143 Novel UN B UNKNOWN ref|YP_001297499.1| two-component system sensor histidine k ... inase/response regulator, hybrid ... [Bacteroides vulgatus ATCC 8482] gb|ABR37877.1| tw ... system sensor histidine kinase/response regulator, hybrid ... [Bacteroides vulgatus ATCC 8482] 9.0 33% gnl|UG|Ga ...

  1. Some new aspects of the pea (Pisum sativum L. root nodule ultrastructure

    Directory of Open Access Journals (Sweden)

    Wojciech Borucki

    2014-02-01

    Full Text Available Unequal cell divisions were observed in the meristem of pea root nodule. Since after such divisions only the bigger cells become infected then those divisions play a significant role in the formation of the three-dimensional structure of the bacteroidal tissue. In the infected cells of the young ineffective bacteroidal tissue the first host reaction to the incompatibility of the symbiotic system is the RER membranes aggregation. In effective symbiosis RER membranes form permanent sites of contact with the peribacteroidal membranes thus connecting all the symbiosoms in the cell. Possibly that ensures the synchronisation of the differentiation processes of the bacteroids and/or their simultaneous degeneration. The presence of membraneous structures in the form of rings is a characteristic feature of effective bacteroids. It is postulated that the structures are directly connected with nitrogen assimilation. Structures X and Y which are present in the bacteroids of the effective and ineffective symbiosis may be connected with the adaptation of bacterial cells to lowered oxygen pressure in bacteroidal tissue and their transformation (structures X into bacteroids. The presence of the cytoplasm (or cytoplasmatic remnants of the infected cells was observed in the intercellular spaces. It is sugested that it is a way, so far unknown, of the gas diffusion regulation in bacteroidal tissue.

  2. Dicty_cDB: Contig-U05223-1 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available 014299_3202( AE014299 |pid:none) Shewanella oneidensis MR-1, com... 36 0.006 AE015928_321( AE015928 |pid:none) Bacteroide...1 0.080 AP006841_706( AP006841 |pid:none) Bacteroides fragilis YCH46 DNA, ... 37 ...enstephanensis KBAB4... 38 0.50 CP000447_1129( CP000447 |pid:none) Shewanella frigidimarina NCIMB ... 38 0.5...:none) Bacteroides fragilis YCH46 DNA,... 37 0.66 AE006914_1285( AE006914 |pid...:none) Burkholderia multivorans ATCC 1... 36 1.5 CP000880_293( CP000880 |pid:none) Salmonella

  3. Dicty_cDB: Contig-U12666-1 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available pha-xylo... 161 3e-38 AB090361_1( AB090361 |pid:none) Mortierella alliacea agdA mRNA for... 160 3e-38 ( Q09901 ) RecName: Full... Agrobacterium tumefaciens str. C... 59 2e-07 AP006841_1248( AP006841 |pid:none) Bacteroides fragilis YCH46 ...us oryzae RIB40 genomic... 57 9e-07 CR626927_476( CR626927 |pid:none) Bacteroides fragili...s NCTC 9343, ... 56 1e-06 AP006841_551( AP006841 |pid:none) Bacteroides fragilis ...5... 55 3e-06 CR626927_1013( CR626927 |pid:none) Bacteroides fragilis NCTC 9343,... 55 3e-06 AE015928_3657( AE015928 |pid

  4. Dicty_cDB: Contig-U12973-1 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available :none) Medicago truncatula clone mth2-78... 36 1.2 AP006841_1399( AP006841 |pid:none) Bacteroides fragi... 71 5e-11 AE014613_3359( AE014613 |pid:none) Salmonella enterica subsp. ente... 70 6e-11 AE015928_3084( AE015928 |pid... enterica subsp. ente... 70 6e-11 AP006841_1248( AP006841 |pid:none) Bacteroides fragi...89 hyp... 70 8e-11 CR626927_476( CR626927 |pid:none) Bacteroides fragilis NCTC 9343, ... 70 1e-10 AP006841_551( AP006841 |pid...:none) Bacteroides fragilis YCH46 DNA, ... 70 1e-10 AE005673_786( AE005673 |pid

  5. Linking Long-Term Dietary Patterns with Gut Microbial Enterotypes

    OpenAIRE

    Wu, Gary D; Jun CHEN; Hoffmann, Christian; Bittinger, Kyle; Chen, Ying-Yu; Keilbaugh, Sue A.; Bewtra, Meenakshi; Knights, Dan; Walters, William A.; Knight, Rob; Sinha, Rohini; Gilroy, Erin; Gupta, Kernika; Baldassano, Robert; Nessel, Lisa

    2011-01-01

    Diet strongly affects human health, partly by modulating gut microbiome composition. We used diet inventories and 16S rDNA sequencing to characterize fecal samples from 98 individuals. Fecal communities clustered into enterotypes distinguished primarily by levels of Bacteroides and Prevotella. Enterotypes were strongly associated with long-term diets, particularly protein and animal fat (Bacteroides) versus carbohydrates (Prevotella). A controlled-feeding study of 10 subjects showed that micr...

  6. Keratinolytic activity of cutaneous and oral bacteria.

    OpenAIRE

    Mikx, F H; De Jong, M H

    1987-01-01

    A test was developed to measure the keratinolytic activity of cutaneous and oral bacteria. Keratin, labeled with fluorescein isothiocyanate, was used in a phosphate buffer (pH 7.2) with 1 mM dithiothreitol. The degradation of keratin was estimated by measuring the fluorescence of the degradation products in the supernatant of the reaction mixtures in a luminescence spectrometer. Several oral and cutaneous bacteria were investigated: Bacteroides gingivalis, Bacteroides intermedius, Treponema d...

  7. 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.

  8. Variation in Microbiome LPS Immunogenicity Contributes to Autoimmunity in Humans.

    Science.gov (United States)

    Vatanen, Tommi; Kostic, Aleksandar D; d'Hennezel, Eva; Siljander, Heli; Franzosa, Eric A; Yassour, Moran; Kolde, Raivo; Vlamakis, Hera; Arthur, Timothy D; Hämäläinen, Anu-Maaria; Peet, Aleksandr; Tillmann, Vallo; Uibo, Raivo; Mokurov, Sergei; Dorshakova, Natalya; Ilonen, Jorma; Virtanen, Suvi M; Szabo, Susanne J; Porter, Jeffrey A; Lähdesmäki, Harri; Huttenhower, Curtis; Gevers, Dirk; Cullen, Thomas W; Knip, Mikael; Xavier, Ramnik J

    2016-05-01

    According to the hygiene hypothesis, the increasing incidence of autoimmune diseases in western countries may be explained by changes in early microbial exposure, leading to altered immune maturation. We followed gut microbiome development from birth until age three in 222 infants in Northern Europe, where early-onset autoimmune diseases are common in Finland and Estonia but are less prevalent in Russia. We found that Bacteroides species are lowly abundant in Russians but dominate in Finnish and Estonian infants. Therefore, their lipopolysaccharide (LPS) exposures arose primarily from Bacteroides rather than from Escherichia coli, which is a potent innate immune activator. We show that Bacteroides LPS is structurally distinct from E. coli LPS and inhibits innate immune signaling and endotoxin tolerance; furthermore, unlike LPS from E. coli, B. dorei LPS does not decrease incidence of autoimmune diabetes in non-obese diabetic mice. Early colonization by immunologically silencing microbiota may thus preclude aspects of immune education. PMID:27133167

  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. 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...... 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 as...... constitute a component of the transfer of nitrogen between the symbionts....

  11. Activity of difloxacin (A-56619) and A-56620 against clinical anaerobic bacteria in vitro.

    OpenAIRE

    Bansal, M B; Thadepalli, H

    1987-01-01

    We determined the MICs of difloxacin (A-56619) and A-56620 against anaerobic bacteria and assessed the effects of alterations in pH, size of inoculum, addition of human serum, and repeated exposure to subinhibitory levels of antibiotics. We tested for synergism of these drugs with cefoxitin against Bacteroides spp. We found that difloxacin and A-56620 were as active as ciprofloxacin, inhibiting about 90% of B. fragilis (4 micrograms/ml) and other Bacteroides spp. (8 micrograms/ml), A-56620 be...

  12. Susceptibility of anaerobic bacteria to carbenicillin.

    Science.gov (United States)

    Blazevic, D J; Matsen, J M

    1974-05-01

    One hundred and seventy-one strains of anaerobes were tested for susceptibility to carbenicillin by using agar dilution, broth dilution, and two disk diffusion methods. The minimal inhibitory concentration (MIC) for 67% of 51 strains of Bacteroides fragilis, 7 of 9 strains of Bacteroides melaninogenicus, and all of 8 strains of Eubacterium was 100 mug or less per ml. The MICs of the remaining anaerobes were 50 mug or less per ml. The broth dilution results were felt to be the most accurate of the four methods utilized. PMID:4462461

  13. Dicty_cDB: Contig-U10802-1 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available 000937_1110( CP000937 |pid:none) Francisella philomiragia subsp.... 82 2e-24 CR925678_560( CR925678 |pid:non...tr. ... 90 2e-27 CP000447_443( CP000447 |pid:none) Shewanella frigidimarina NCIMB 4... 84 2e-27 CP000931_3877( CP000931 |pid...:none) Shewanella oneidensis MR-1, com... 80 3e-26 CP000510_40( CP000510 |pid...:none) Bacteroides fragilis NCTC 9343,... 80 1e-23 AP006841_3046( AP006841 |pid...:none) Bacteroides fragilis YCH46 DNA,... 80 1e-23 CP001197_348( CP001197 |pid:none) Desulfovi

  14. [BACTERIOLOGICAL ASPECTS OF AN ACUTE APPENDICITIS].

    Science.gov (United States)

    Zhuchenko, O P

    2016-03-01

    Peculiarities of microflora in the appendix mucosa and abdominal exudate in different morphological forms of an acute appendicitis (AA) were studied up. In accordance to the bacteriological investigations data, anaerobic, and aerobic microorganisms in AA were revealed in a monoculture and in association, more frequently--obligate anaer- obes (bacteroids) with E. coli--in 82 (80.39%) observations, staphylococcus--in 52 (50.98%), fecal streptococcus--in 19 (18.63%). With progression of inflammatory process and destructive changes in the appendix wall the quantity of bacteroids and enterobacteria have had enhanced, while the quantity of lacto- and bifidumflora-- reduced. PMID:27514082

  15. Chemical and physical differentiation of superoxide dismutases in anaerobes.

    OpenAIRE

    Gregory, E M; Dapper, C H

    1980-01-01

    Superoxide dismutase activity in crude or partially purified cell extracts from several species and strains of obligate anaerobe Bacteroides was inhibited instantaneously by NaN3 and was inactivated rapidly upon incubation with H2O2. The extent of NaN3 inhibition varied from 41 to 93%, and the half-life of the enzymatic activity in 5 mM H2O2 ranged from 1.2 to 6.1 min, depending upon the organism tests. When grown in a defined medium containing 59Fe, Bacteroides fragilis (VPI 2393) incorporat...

  16. 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.

  17. [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. PMID:2638022

  18. Papel de las bacterias anaerobias en la etiopatogenia de la patología pulpoperiapical

    OpenAIRE

    Pumarola Suñé, José; Brau Aguadé, Esteban; Canalda Sahli, Carlos

    1993-01-01

    La mayor prevalencia de especies microbianas estrictamente anaerobias en las lesiones periapicales, particularmente Bacteroides pigmentados, y las recientes taxonomías aprobadas para determinadas especies de este grupo bacteriano ha motivado la revisión de la relevancia que tienen estos microorganismos en la etiopatogenia pulpoperiapical.

  19. Gut Microbes Take Their Vitamins

    OpenAIRE

    Sonnenburg, Erica D.; Sonnenburg, Justin L.

    2014-01-01

    The dense microbial ecosystem within the gut is connected through a complex web of metabolic interactions. In this issue of Cell Host & Microbe, Degnan et al. (2014) establish the importance of different vitamin B12transporters that help a Bacteroides species acquire vitamins from the environment tomaintain a competitive edge.

  20. In vitro activity of pipecolic acid amide of clindamycin (U-57930E) on anaerobic bacteria compared with those of clindamycin, cefoxitin, and chloramphenicol.

    OpenAIRE

    Dhawan, V K; Bansal, M B; Thadepalli, H

    1982-01-01

    In vitro activity of pipecolic acid amide of clindamycin (U-57930E) against 265 isolates of anaerobic bacteria, including 66 strains of Bacteroides fragilis, was compared with those of clindamycin, chloramphenicol, and cefoxitin. At therapeutically achievable concentrations, the activities of all four antibiotics against anaerobic bacteria were similar.

  1. Dicty_cDB: SSC160 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available argivasghy ksnqivltrrtlekiqhlkdeegfqitsdnleaankcailiigvlpaqvpqllesikhlv tkdhiiisvvlgitisgirshlqpdvytpivrampntai...hy ksnqivltrrtlekiqhlkdeegfqitsdnleaankcailiigvlpaqvpqllesikhlv tkdhiiisvvlgitisgirshlqpdvytpivrampntaiqnp*h...8 |pid:none) Bacteroides thetaiotaomicron VP... 120 1e-25 CP001175_2211( CP001175 |pid:none) Listeria monocy...Translated Amino Acid sequence vnnkfylyfkkiiikkkkk*kkkn*kmvatdlknnkniailgsgnlgvsi...nslated Amino Acid sequence (All Frames) Frame A: vnnkfylyfkkiiikkkkk*kkkn*kmvatdlknnkniailgsgnlgvsiargivasg

  2. Enzyme Profile of Lactobacillus Strain GG by a Rapid API ZYM System: A Comparison of Intestinal Bacterial Strains

    OpenAIRE

    Ling, W H; Saxelin, M.; Hanninen, O.; Salminen, S

    2011-01-01

    Lactobacillus GG and eight strains of lactobacilli (L. acidophilus, L. rhamnosus, L. bulgaricus and L. helviticus) and other clinical organisms (Escherichia coli, Peptostreptococcus anaerobius, Bacteroides fragilis and Clostridium difficile) were compared for their enzyme profiles. Specific activities of 19 hydrolytic enzymes for each strain were determined using the microenzyme API ZYM system. Lactobacillus GG enzyme profile showed high peptidase, chymotrypsin and phosphatase activities, and...

  3. An antibacterial assay of aqueous extract of garlic against anaerobic/microaerophilic and aerobic bacteria

    OpenAIRE

    Elsom, Giles K.; Hide, Denis; Salmon, David M.

    2011-01-01

    Both the minimum inhibitory and minimum bactericidal concentration (expressed in terms of thiosulphinate concentration) of an aqueous extract of garlic was determined against nine species of bacteria. Helicobacter pylori proved to be extremely sensitive to garlic extract, whilst Bacteroides fragilis, Clostridium perfringens, Enterobacter cloacae, Escherichia coli, Pseudomonas aeruginosa, Salmonella typhimurium and Staphylococcus aureus all were moderately sensitive to the garlic extract treat...

  4. 21 CFR 520.447 - Clindamycin solution.

    Science.gov (United States)

    2010-04-01

    ... (Staphylococcus aureus or S. intermedius), deep wounds and abscesses due to susceptible strains of Bacteroides... infections due to susceptible strains of S. aureus, B. fragilis, P. melaninogenicus, F. necrophorum, and C. perfringens; and osteomyelitis due to susceptible strains of S. aureus, B. fragilis, P. melaninogenicus,...

  5. Inconsistency of Synergy Between the β-Lactamase Inhibitor CP-45,899 and β-Lactam Antibiotics Against Multiply Drug-Resistant Enterobacteriaceae and Pseudomonas Species

    OpenAIRE

    Fass, Robert J.

    1981-01-01

    Synergy between CP-45,899 and ampicillin or newer β-lactam antibiotics against multiply drug-resistant Enterobacteriaceae and Pseudomonas species was inconsistent. In contrast, synergy between CP-45,899 and ampicillin against β-lactamase-producing strains of Haemophilus influenzae type b and Bacteroides fragilis was consistent and marked.

  6. Turnover of nitrogenase and leghemoglobin in root nodules of Pisum sativum

    NARCIS (Netherlands)

    Bisseling, T.; Straten, van J.; Houwaard, F.

    1980-01-01

    Turnover rates of the two nitrogenase components and leghemoglobin in root nodules of pea plants nodulated with Rhizobium leguminosarum were determined with three different methods: 1, Kinetics of 35S incorporation into protein; 2, pulse-chase experiments; 3, chloramphenicol inhibition of bacteroid

  7. Uterine Microbiota Progression from Calving until Establishment of Metritis in Dairy Cows

    Science.gov (United States)

    Jeon, Soo Jin; Vieira-Neto, Achilles; Gobikrushanth, Mohanathas; Daetz, Rodolfo; Mingoti, Rodolfo D.; Parize, Ana Carolina Brigolin; de Freitas, Sabrina Lucas; da Costa, Antonio Nelson Lima; Bicalho, Rodrigo C.; Lima, Svetlana; Jeong, K. Casey

    2015-01-01

    The objective of this study was to evaluate the progression of the uterine microbiota from calving until establishment of metritis. Uterine swabs (n = 72) collected at 0, 2, and 6 ± 2 days postpartum (dpp) from 12 metritic and 12 healthy cows were used for metagenomic sequencing of the 16S rRNA gene on the Illumina MiSeq platform. A heat map showed that uterine microbiota was established at calving. The microbiota changed rapidly from 0 to 6 ± 2 dpp, with a decrease in the abundance of Proteobacteria and an increase in the abundance of Bacteroidetes and Fusobacteria, which were dominant in metritic cows. Uterine microbiota composition was shared; however, metritic and healthy cows could be discriminated using relative abundance of bacterial genera at 0, 2, and 6 ± 2 dpp. Bacteroides was the main genus associated with metritis because it was the only genus that showed significantly greater abundance in cows with metritis. As the abundance of Bacteroides organisms increased, the uterine discharge score, a measure of uterine health, worsened. Fusobacterium was also an important genus associated with metritis because Fusobacterium abundance increased as Bacteroides abundance increased and the uterine discharge score worsened as the abundance increased. The correlation with uterine discharge score and the correlation with Bacteroides or Fusobacterium showed that other bacteria, such as Helcoccocus, Filifactor, and Porphyromonas, were also associated with metritis. There were also bacteria associated with uterine health, such as “Candidatus Blochmannia,” Escherichia, Sneathia, and Pedobacter. PMID:26150453

  8. Interactions between Periodontal Bacteria and Human Oral Epithelial Cells: Fusobacterium nucleatum Adheres to and Invades Epithelial Cells

    OpenAIRE

    Han, Yiping W.; Shi, Wenyuan; HUANG, GEORGE T.-J.; Kinder Haake, Susan; Park, No-Hee; Kuramitsu, Howard; Genco, Robert J.

    2000-01-01

    Bacteria are causative agents of periodontal diseases. Interactions between oral bacteria and gingival epithelial cells are essential aspects of periodontal infections. Using an in vitro tissue culture model, a selected group of gram-negative anaerobic bacteria frequently associated with periodontal diseases, including Bacteroides forsythus, Campylobacter curvus, Eikenella corrodens, Fusobacterium nucleatum, Porphyromonas gingivalis, and Prevotella intermedia, were examined for their ability ...

  9. Antimicrobial activity of Ethiopian medicinal plants

    OpenAIRE

    Bernášková, Eva

    2013-01-01

    In vitro antimicrobial activity of eighteen Ethiopian medicinal plant species that were selected based on ethnobotanical information on their traditional use to treat infectious diseases was determined by the broth microdilution method. The antimicrobial activity of ethanol extracts of selected plants against potentially pathogenic microorganism such as Bacillus cereus, Bacteroides fragilis, Candida albicans, Clostridium perfringens, Enterococcus faecalis, Escherichia coli, Listeria monocytog...

  10. 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...

  11. [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. PMID:24630580

  12. 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...... membrane, called peribacteroid space (PS), mediate the exchange of metabolites between the symbionts. Proteome analysis was used as an approach to characterise the proteins in the PBM and the PS. A standard differential centrifugation procedure including a Percoll gradient was used for symbiosome isolation...... from pea root nodules. Proteins in the PBM and PS fractions obtained from the symbiosomes were separated by two-dimensional gel electrophoresis, and 89 spots were analysed by tandem mass spectrometry. The proteins of 46 spots could be identified by database search. The results showed that PS and even...

  13. AcEST: DK956327 [AcEST

    Lifescience Database Archive (English)

    Full Text Available istoyl] glucosamine N-acyltransferase OS=Bacteroides thetaiotaomicron Align length 40 Score (bit) 33.1 E-value 1.1 Rep...ase OS=Bacteroides thetaiotaomicron GN=lpxD PE=3 SV=1 Length = 346 Score = 33.1 bits (74), Expe...SIGSRCVIHSGAVIGAD-GFGFAPNA 190 >sp|P16716|RPO2_SHEVK DNA-directed RNA polymerase 132 kDa polypeptide (Fragment) OS=Sheepp... N-... 31 5.3 sp|A6KWL3|LPXD_BACV8 UDP-3-O-[3-hydroxymyristoyl] glucosamine N-... 31 5.3 sp|Q23915|KINX_DICDI Probable serine/threoni..., Jinghui Zhang, Zheng Zhang, Webb Miller, and David J. Lipman (1997), Gapped BLAST and PSI-BLAST: a new generation

  14. In vitro activity of ceftriaxone combined with tazobactam against anaerobic bacteria.

    Science.gov (United States)

    Wüst, J; Hardegger, U

    1994-02-01

    The in vitro activity of ceftriaxone combined with tazobactam against 190 strains of anaerobic bacteria was compared with that of amoxicillin with clavulanic acid, ampicillin with sulbactam, piperacillin alone and with tazobactam, cefoxitin, and imipenem, i.e. beta-lactam antibiotics established in the treatment of anaerobic infections. All anaerobes tested were susceptible to ceftriaxone when tazobactam was added at fixed ratios (ceftriaxone to tazobactam) of 2:1 and 8:1 and at constant concentrations of 2,4 and 8 mg/l, respectively. When 4 mg/l tazobactam was added, the MICs of ceftriaxone for 83 of 94 strains of the Bacteroides fragilis group were reduced by a factor of 8 to 512; for eight strains, this reduction was two to fourfold. Only the MICs of ceftriaxone for three Bacteroides fragilis strains were not influenced. PMID:8013494

  15. AcEST: DK949777 [AcEST

    Lifescience Database Archive (English)

    Full Text Available _PORGI UDP-3-O-[3-hydroxymyristoyl] glucosamine N-acyltransferase OS=Porphyromonas gingivalis GN=lpxD PE=3 SV=1 Leng...PAEFKDGYVASSLVGINHNSGPRAILGC 447 >sp|Q64XW8|LPXD_BACFR UDP-3-O-[3-hydroxymyristoyl] glucosamine N-acyltransferase OS=Bacteroides fra...DP-3-O-[3-hydroxymyristoyl] glucosamine N-acyltransferase OS=Bacteroides thetaiotaomicron GN=lpxD PE=3 SV=1 Leng...ition sp|Q8A014|LPXD_BACTN UDP-3-O-[3-hydroxymyristoyl] glucosamine N-acyltransferase OS...|LPXD_BACTN UDP-3-O-[3-hydroxymyristoyl] glucosamine N-... 33 1.4 sp|P33191|TUB8_SOLTU Induced stolen tip protein TUB8 (Fra

  16. Dicty_cDB: CHQ735 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available tein Score E Sequences producing significant alignments: (bits) Value AF331669_1( AF331669 |pid:none) Drom...ome Xq27.1-27.3. Contains STSs and GSSs. 52 0.016 1 CV653915 |CV653915.1 TgESTzyr...-17 L78465_1( L78465 |pid:none) Human alpha-N-acetylglucosaminidase (u... 92 2e-17 AE015928_3588( AE015928 |pid:none) Bacteroi...RNA for alph... 85 2e-15 AP006841_677( AP006841 |pid:none) Bacteroides fragilis YCH46 DNA, ... 82 2e-14 CR62...6927_576( CR626927 |pid:none) Bacteroides fragilis NCTC 9343, ... 82 2e-14 BX2559

  17. Dicty_cDB: SHE175 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available ducing significant alignments: (bits) Value AF331669_1( AF331669 |pid:none) Dro...mosome Xq27.1-27.3. Contains STSs and GSSs. 52 0.016 1 CV653915 |CV653915.1 TgESTzyr93e08.y1 Tg COUG Tachyzoit...( L78465 |pid:none) Human alpha-N-acetylglucosaminidase (u... 84 5e-15 AE015928_3588( AE015928 |pid:none) Bacteroi...des thetaiotaomicron VP... 83 8e-15 AP006841_677( AP006841 |pid:none) Bacteroides fragilis YCH46 DNA, ...... 79 1e-13 CP000312_824( CP000312 |pid:none) Clostridium perfringens SM101, c... 79 1e-13 CR626927_576( CR

  18. 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

    positive correlation was observed between the increase in body mass index and the increase of the short-chain-fatty-acid-producing clostridia, the Clostridum leptum group, and Eubacterium hallii. Considering previously established positive associations between rapid infant weight gain, early breastfeeding......Fecal samples were obtained from a cohort of 330 healthy Danish infants at 9, 18, and 36 months after birth, enabling characterization of interbacterial relationships by use of quantitative PCR targeting 31 selected bacterial 16S rRNA gene targets representing different phylogenetic levels...... 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...

  19. Helminth infection promotes colonization resistance via type 2 immunity.

    Science.gov (United States)

    Ramanan, Deepshika; Bowcutt, Rowann; Lee, Soo Ching; Tang, Mei San; Kurtz, Zachary D; Ding, Yi; Honda, Kenya; Gause, William C; Blaser, Martin J; Bonneau, Richard A; Lim, Yvonne A L; Loke, P'ng; Cadwell, Ken

    2016-04-29

    Increasing incidence of inflammatory bowel diseases, such as Crohn's disease, in developed nations is associated with changes to the microbial environment, such as decreased prevalence of helminth colonization and alterations to the gut microbiota. We find that helminth infection protects mice deficient in the Crohn's disease susceptibility gene Nod2 from intestinal abnormalities by inhibiting colonization by an inflammatory Bacteroides species. Resistance to Bacteroides colonization was dependent on type 2 immunity, which promoted the establishment of a protective microbiota enriched in Clostridiales. Additionally, we show that individuals from helminth-endemic regions harbor a similar protective microbiota and that deworming treatment reduced levels of Clostridiales and increased Bacteroidales. These results support a model of the hygiene hypothesis in which certain individuals are genetically susceptible to the consequences of a changing microbial environment. PMID:27080105

  20. Dicty_cDB: Contig-U16162-1 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available :none) Bacteroides fragilis NCTC 9343,... 93 5e-17 AJ720350_1( AJ720350 |pid..... 93 5e-17 AP006841_4502( AP006841 |pid:none) Bacteroides fragilis YCH46 DNA,....... 90 3e-16 CP000447_3212( CP000447 |pid:none) Shewanella frigidimarina NCIMB ... ...87 2e-15 CP000509_1657( CP000509 |pid:none) Nocardioides sp. JS614, complet... 87 2e-15 CP000155_268( CP000155 |pid:none) Hahella... Ich... 46 1.9 2 ( EL906924 ) INIT2_15_G06.b1_A006 G5 trophont cDNA (INIT2) Ich... 46 1.9 2 ( AF148983 ) Legionella dr

  1. Linking long-term dietary patterns with gut microbial enterotypes.

    Science.gov (United States)

    Wu, Gary D; Chen, Jun; Hoffmann, Christian; Bittinger, Kyle; Chen, Ying-Yu; Keilbaugh, Sue A; Bewtra, Meenakshi; Knights, Dan; Walters, William A; Knight, Rob; Sinha, Rohini; Gilroy, Erin; Gupta, Kernika; Baldassano, Robert; Nessel, Lisa; Li, Hongzhe; Bushman, Frederic D; Lewis, James D

    2011-10-01

    Diet strongly affects human health, partly by modulating gut microbiome composition. We used diet inventories and 16S rDNA sequencing to characterize fecal samples from 98 individuals. Fecal communities clustered into enterotypes distinguished primarily by levels of Bacteroides and Prevotella. Enterotypes were strongly associated with long-term diets, particularly protein and animal fat (Bacteroides) versus carbohydrates (Prevotella). A controlled-feeding study of 10 subjects showed that microbiome composition changed detectably within 24 hours of initiating a high-fat/low-fiber or low-fat/high-fiber diet, but that enterotype identity remained stable during the 10-day study. Thus, alternative enterotype states are associated with long-term diet. PMID:21885731

  2. Assessment of serum antibody patterns and analysis of subgingival microflora of members of a family with a high prevalence of early-onset periodontitis.

    OpenAIRE

    Williams, B L; Ebersole, J. L.; Spektor, M D; Page, R C

    1985-01-01

    In a study of members of a large family with a high prevalence of early-onset periodontitis, we sampled the subgingival microflora and characterized 40 isolates from each sample. We surveyed serum samples by enzyme-linked immunosorbent assay for antibodies reacting with any of a panel of 21 periodontal bacteria. The mother and 7 of her 13 children had early-onset periodontitis. Bacteroides gingivalis was not detected in the subgingival flora of any affected or unaffected family member, and Ac...

  3. Přirozená a syntetická prebiotika ve výživě zvířat

    OpenAIRE

    Keřtofová, Ivana

    2013-01-01

    Prebiotics are a different indigestible food ingredients, which pass into the colon through the digestive tract of a living organism and there selectively stimulate the growth of a limited number (1 to 50) of the genera of bacteria (Bifidobacteria, Lactobacillus, Eubacteria, Bacteroides, Gram-positive cocci, etc.). These bacteria are able to cleave undigested nutrients on short fatty acids (acetic, butyric) by microbial enzymes. These acids are the energy source for macroorganism and microorg...

  4. Effect of soluble carbohydrates on digestion of cellulose by pure cultures of rumen bacteria.

    OpenAIRE

    Hiltner, P; Dehority, B. A.

    1983-01-01

    The rate of cellulose digestion in the presence of either glucose or cellobiose was studied for the three predominant species of cellulolytic rumen bacteria: Ruminococcus albus, Ruminococcus flavefaciens, and Bacteroides succinogenes. When a soluble carbohydrate was added to cellulose broth, the lag phase of cellulose digestion was shortened. Presumably, this was due to greater numbers of bacteria, because increasing the size of the inoculum had a similar effect. Cellulose digestion occurred ...

  5. A highly sensitive method for detection of molybdenum-containing proteins

    International Nuclear Information System (INIS)

    A highly sensitive method for detection of molybdenum-containing proteins in gels after electrophoresis has been developed. The method involves in vitro labeling of the proteins with the radioactive isotope 185W. The method used to detect molybdenum-accumulating proteins in lupine seeds, xanthine dehydrogenase and another molybdenum-containing protein in wheat, barley, and pea seedlings, and nitrate reductase and xanthine dehydrogenase in bacteroides from lupine nodules. Nitrogenase could not be detected by the method. 16 refs., 5 figs

  6. In Vitro Activities of Doripenem and Six Comparator Drugs against 423 Aerobic and Anaerobic Bacterial Isolates from Infected Diabetic Foot Wounds▿

    OpenAIRE

    Goldstein, Ellie J. C.; Citron, Diane M.; Merriam, C. Vreni; Warren, Yumi A.; Tyrrell, Kerin L.; Fernandez, Helen T.

    2007-01-01

    Against 182 anaerobe and 241 aerobe strains obtained from diabetic foot infections, doripenem was the most active carbapenem against Pseudomonas aeruginosa (MIC90, 2 μg/ml), more active than imipenem against Proteus mirabilis, and ertapenem was more active against Escherichia coli and Klebsiella spp. The MIC50 and MIC90 values were ≤0.125 μg/ml for methicillin-sensitive Staphylococcus aureus and all streptococci and 0.25/1 for Bacteroides fragilis.

  7. 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 ...

  8. Distribution of amoxicillin and clavulanic acid in infected animals and efficacy against experimental infections.

    OpenAIRE

    Boon, R J; Beale, A S; Comber, K. R.; Pierce, C V; Sutherland, R.

    1982-01-01

    The therapeutic effects produced by formulations of amoxicillin plus clavulanic acid (BRL 25 000A and BRL 25 000G) were compared with those of amoxicillin and clavulanic acid separately against a variety of infections produced by amoxicillin-susceptible and beta-lactamase-producing (amoxicillin-resistant) bacteria. The infection models studied included intraperitoneal infections, a mouse pneumonia, experimental pyelonephritis, and local lesions caused by Staphylococcus aureus and Bacteroides ...

  9. Characterization of a novel tetracycline resistance that functions only in aerobically grown Escherichia coli.

    OpenAIRE

    Speer, B S; Salyers, A A

    1988-01-01

    A tetracycline resistance (Tcr) gene that was found originally on two Bacteroides plasmids (pBF4 and pCP1) confers tetracycline resistance on Escherichia coli, but only when it is grown aerobically. Using maxicells, we have identified a 44-kilodalton protein which is encoded by the region that carries the Tcr gene and which may be the Tcr gene product. Localization experiments indicate that this 44-kilodalton protein is cytoplasmic. To determine whether the tetracycline resistance gene is exp...

  10. The cryptic tetracycline resistance determinant on Tn4400 mediates tetracycline degradation as well as tetracycline efflux.

    OpenAIRE

    Park, B. H.; Levy, S. B.

    1988-01-01

    Escherichia coli containing the cryptic tetracycline resistance determinant (class F) from the Bacteroides fragilis transposon Tn4400 on plasmid pGAT400 expressed a detoxification of tetracycline as well as an active efflux of tetracycline. This finding concurs with the report of detoxification for a related tetracycline resistance determinant from B. fragilis on Tn4351 (B. S. Speer and A. Salyers, J. Bacteriol. 170:1423-1429, 1987), which specifies a 10-fold-higher resistance than Tn4400. In...

  11. 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| mult ... idrug efflux pump ... BexA [Parabacteroides sp. D13] gb|EEY81680.1| mult ...

  12. In vitro activity of biapenem (L-627), a new carbapenem, against anaerobes.

    OpenAIRE

    Aldridge, K E; MORICE,N; Schiro, D D

    1994-01-01

    We tested 441 clinical strains of anaerobes by using a broth microdilution method to determine the in vitro activity of biapenem for comparison with those of other agents. Biapenem had activity comparable to those of imipenem and meropenem against all groups of anaerobes with MICs for 90% of the strains tested of 0.06 to 2 micrograms/ml. Against the Bacteroides fragilis group, biapenem was more active than ampicillin-sulbactam, ticarcillin-clavulanate, piperacillin, cefoxitin, cefotaxime, and...

  13. Characterization of the bacterial community associated with body wall lesions of Tripneustes gratilla (Echinoidea) using culture-independent methods

    OpenAIRE

    Becker, P.; Gillan, D.C.; Eeckhaut, I.

    2009-01-01

    The bacterial community associated with skin lesions of the sea urchin Tripneustes gratilla was investigated using 16S ribosomal RNA gene cloning and fluorescent in situ hybridization (FISH). All clones were classified in the Alphaproteobacteria, Gammaproteobacteria and Cytophaga-Flexibacter-Bacteroides (CFB) bacteria. Most of the Alphaproteobacteria were related to the Roseobacter lineage and to bacteria implicated in marine diseases. The majority of the Gammaproteobacteria were identified a...

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

    OpenAIRE

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

    2003-01-01

    Background and aims: 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 investigated if Lactobacillus rhamnosus GG (L GG) can prevent colitis in TG rats monoassociated with B vulgatus and if L GG or Lactobacillus plantarum 299v (LP 299v) can treat establishe...

  15. Fluoroquinolone Resistance in Anaerobic Bacteria following Exposure to Levofloxacin, Trovafloxacin, and Sparfloxacin in an In Vitro Pharmacodynamic Model

    OpenAIRE

    Ross, Gigi H.; Wright, David H.; Hovde, Laurie Baeker; Peterson, Marnie L.; Rotschafer, John C.

    2001-01-01

    This investigation explored pharmacodynamic characteristics of fluoroquinolones against Bacteroides thetaiotamicron and the potential for development of resistance. An in vitro model was used to generate kill curves with three fluoroquinolones at various area under the concentration-time curve (AUC)/MIC ratios. Concentration-independent killing was observed. Increases in MICs were noted following exposure to fluoroquinolones at AUC/MIC ratios of 6 to 14.

  16. Prebiotics and human health: The state-of-the-art and future perspectives

    OpenAIRE

    Conway, Patricia L

    2001-01-01

    Prebiotics stimulate growth and/or activity of some presumably beneficial colonic bacteria and thereby have the potential to improve health, possibly through the actions of fermentation end products including butyrate. Some ingested oligosaccharides and resistant starches elevate levels of bifidobacteria and lactobacilli, and decrease bacteroides, enterobacteria and clostridia. Rodent studies have shown that prebiotic consumption can protect against pathogens, reduce the risk of colon cancer,...

  17. Mpi recombinase globally modulates the surface architecture of a human commensal bacterium

    OpenAIRE

    Coyne, Michael J.; Weinacht, Katja G.; Krinos, Corinna M.; Comstock, Laurie E.

    2003-01-01

    The mammalian gut represents a complex and diverse ecosystem, consisting of unique interactions between the host and microbial residents. Bacterial surfaces serve as an interface that promotes and responds to this dynamic exchange, a process essential to the biology of both symbionts. The human intestinal microorganism, Bacteroides fragilis, is able to extensively modulate its surface. Analysis of the B. fragilis genomic sequence, together with genetic conservation ana...

  18. Synergism in Degradation and Utilization of Intact Forage Cellulose, Hemicellulose, and Pectin by Three Pure Cultures of Ruminal Bacteria †

    OpenAIRE

    Osborne, J. M.; Dehority, B. A.

    1989-01-01

    Pure cultures of ruminal bacteria characterized as using only a single forage polysaccharide (Fibrobacter succinogenes A3c, cellulolytic; Bacteroides ruminicola H2b, hemicellulolytic; Lachnospira multiparus D15d, pectinolytic) were inoculated separately and in all possible combinations into fermentation tubes containing orchard grass as the sole substrate. Fermentations were run to completion, and then cultures were analyzed for digestion of cellulose plus degradation and utilization of hemic...

  19. Bases farmacomicrobiológicas del tratamiento antibiótico de las enfermedades periodontales y periimplatarias Farmacobiological concepts in the antibiotic treatment of the periodontal diseases

    OpenAIRE

    Liñares, J.; J.E. Martín-Herrero

    2003-01-01

    La enfermedad periodontal debe considerarse un proceso infeccioso bacteriano crónico. En su etiología, no hay una única especie bacteriana implicada, sino que podríamos considerarla como una infección polimicrobiana en la que estarían implicados diversos microorganismos. Las bacterias que se han asociado más directamente con la enfermedad periodontal son Actinobacillus actinomycetemcomitans, Porphyromonas gingivalis, Prevotella intermedia, Bacteroides forsythus y Treponema denticola. Los pará...

  20. Association of Fecal Indicator Bacteria with Human Viruses and Microbial Source Tracking Markers at Coastal Beaches Impacted by Nonpoint Source Pollution

    OpenAIRE

    McQuaig, Shannon; GRIFFITH John; Harwood, Valerie J.

    2012-01-01

    Water quality was assessed at two marine beaches in California by measuring the concentrations of culturable fecal indicator bacteria (FIB) and by library-independent microbial source tracking (MST) methods targeting markers of human-associated microbes (human polyomavirus [HPyV] PCR and quantitative PCR, Methanobrevibacter smithii PCR, and Bacteroides sp. strain HF183 PCR) and a human pathogen (adenovirus by nested PCR). FIB levels periodically exceeded regulatory thresholds at Doheny and Av...

  1. 6 beta-Iodopenicillanic acid (UI-38,006), a beta-lactamase inhibitor that extends the antibacterial spectrum of beta-lactam compounds: initial bacteriological characterization.

    OpenAIRE

    Moore, B A; Brammer, K W

    1981-01-01

    UK-38,006, 6 beta-iodopenicillanic acid, was shown to be a potent inhibitor of beta-lactamase enzymes. It potentiated the antibacterial action of ampicillin in vitro against beta-lactamase-producing strains of Staphylococcus aureus, Haemophilus influenzae, Bacteroides fragilis. Neisseria gonorrhoeae, and many Enterobacteriaceae. This ability to synergize with ampicillin was also demonstrated in vivo after oral administration of UK-38,006 to experimentally infected mice. UK-38,006 was also sho...

  2. The pathophysiology of necrotizing enterocolitis in preterm infants: New insights in the interaction between the gut and its microbiota

    OpenAIRE

    Heida, Fardou Hadewych

    2016-01-01

    Necrotizing enterocolitis (NEC) is a severe gastrointestinal disorder affecting the preterm infant. The underlying cause of NEC is partly unknown. This thesis studied the gut flora, the intestinal barrier function, and the intestinal bloodcirculation contributing to NEC. We observed NEC-associated bacteria (Clostridium perfringens and Bacteroides dorei) within the first baby poop after birth (meconium). These bacteria might predispose the intestine to an early inflammatory reaction. We also o...

  3. Cefotetan, a new cephamycin: comparison of in vitro antimicrobial activity with other cephems, beta-lactamase stability, and preliminary recommendations for disk diffusion testing.

    OpenAIRE

    Ayers, L W; Jones, R N; Barry, A. L.; Thornsberry, C; Fuchs, P C; Gavan, T L; Gerlach, E H; Sommers, H M

    1982-01-01

    Cefotetan is a new, potent, 7 alpha-methoxy cephalosporin (cephamycin). The in vitro activity of cefotetan tested in a multiphasic, collaborative study against 12,260 consecutive clinical isolates and 448 selected isolates showed 93% of Enterobacteriaceae, 90% of methicillin-susceptible Staphylococcus aureus (broth dilution), 83% of Bacteroides fragilis, and 72% of non-enterococcal streptococci to be inhibited by less than or equal to 8 micrograms/ml. Beta-Lactamase-producing and -nonproducin...

  4. The Effects of Maturation on the Colonic Microflora in Infancy and Childhood

    OpenAIRE

    Enck, P.; Zimmermann, K.; Rusch, K.; A. Schwiertz; S. Klosterhalfen; Frick, J. S.

    2009-01-01

    The composition of colonic mircoflora and its changes with maturation have rarely been investigated in large samples. Methods. We used conventional microbiological testing to analyse the colonic flora (Kyberstatus, Institut forMicroecology, Herborn, Germany) of stool samples from 12 484 children with different intestinal and nonintestinal diagnoses. Stool samples were analysed for total colony forming units (CFU) (per g stool) and the abundance of Bifidobacteria, Bacteroides sp., Escherichia ...

  5. Molecular genetic studies on obligate anaerobic bacteria

    International Nuclear Information System (INIS)

    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

  6. Effect of oxygen and temperature on the dynamic of the dominant bacterial populations of pig manure and on the persistence of pig-associated genetic markers, assessed in river water microcosms

    OpenAIRE

    2011-01-01

    Aims: The aim is to evaluate the dynamic of Bacteroides-Prevotella and Bacillus-Streptococcus-Lactobacillus populations originating from pig manure and the persistence of pig-associated markers belonging to these groups according to temperature and oxygen. Methods and Results: River water was inoculated with pig manure and incubated under microaerophilic and aerobic conditions, at 4 and 20 degrees C over 43 days. The diversity of bacterial populations was analysed by capillary electrophoresis...

  7. Identification of Nonpoint Sources of Fecal Pollution in Coastal Waters by Using Host-Specific 16S Ribosomal DNA Genetic Markers from Fecal Anaerobes

    OpenAIRE

    Bernhard, Anne E.; Field, Katharine G.

    2000-01-01

    We describe a new PCR-based method for distinguishing human and cow fecal contamination in coastal waters without culturing indicator organisms, and we show that the method can be used to track bacterial marker sequences in complex environments. We identified two human-specific genetic markers and five cow-specific genetic markers in fecal samples by amplifying 16S ribosomal DNA (rDNA) fragments from members of the genus Bifidobacterium and the Bacteroides-Prevotella group and performing leng...

  8. Bacterial Vaginosis Biofilms: Challenges to Current Therapies and Emerging Solutions

    OpenAIRE

    Machado, Daniela; Castro, Joana; Palmeira-de-Oliveira, Ana; Martinez-de-Oliveira, José; Cerca, Nuno

    2016-01-01

    Bacterial vaginosis (BV) is the most common genital tract infection in women during their reproductive years and it has been associated with serious health complications, such as preterm delivery and acquisition or transmission of several sexually transmitted agents. BV is characterized by a reduction of beneficial lactobacilli and a significant increase in number of anaerobic bacteria, including Gardnerella vaginalis, Atopobium vaginae, Mobiluncus spp., Bacteroides spp. and Prevotella spp.. ...

  9. Comparative inhibition of bacterial and microsomal 3-ketodihydrosphingosine synthetases by L-cycloserine and other inhibitors.

    OpenAIRE

    Sundaram, K S; Lev, M

    1984-01-01

    Eleven compounds were examined for their capacity to inhibit the first enzyme of the sphingolipid pathway, 3-ketodihydrosphingosine synthetase. Of these, L-cycloserine was the most potent, affecting both bacterial and brain microsomal enzymes to a significant degree at 0.04 mM. D- and L-cycloserine irreversibly inactivated the enzyme, indicating a suicide substrate mode of action. L-Cycloserine was a more potent inhibitor of the growth of Bacteroides levii than was D-cycloserine, indicating t...

  10. Modulation of the Colonic Bacterial Flora Affects Differently Bacterial Translocation and Liver Injury in an Acute Liver Injury Model

    OpenAIRE

    Adawi, Diya; Molin, Göran; Ahrné, Siv; Jeppsson, Bengt

    2011-01-01

    Objective: To evaluate the effects of the administration of different bacterial strains on the extent of liver injury and bacterial translocation in an acute liver injury model. Design: Experimental study. Setting: University hospital, Sweden. Subjects: Sprague–Dawley rats. Interventions: Six different bacterial strains (Bacteroides fragilis ATCC 25285T, Enterococcus faecium No.1, Enterococcus faecium No.2, Escherichia coli F131, Lactobacillus plantarum DSM 6595, and Bifidobacterium lon...

  11. Ciprofloxacin, a quinolone carboxylic acid compound active against aerobic and anaerobic bacteria.

    OpenAIRE

    Chin, N X; Neu, H C

    1984-01-01

    The in vitro activity of ciprofloxacin, a quinolone-carboxylic acid derivative, was compared with those of norfloxacin, cefotaxime, cephalexin, ceftazidime, moxalactam, amoxicillin, and methicillin and other agents, as appropriate. The MICs of ciprofloxacin for 90% of members of the family Enterobacteriaceae and for Pseudomonas aeruginosa, Neisseria spp., and Bacteroides fragilis were between 0.005 and 0.8 micrograms/ml, whereas streptococci and staphylococci were all inhibited by less than o...

  12. Soluble CD14 and CD83 from Human Neonatal Antigen-Presenting Cells Are Inducible by Commensal Bacteria and Suppress Allergen-Induced Human Neonatal Th2 Differentiation▿ †

    OpenAIRE

    Lundell, Anna-Carin; Andersson, Kerstin; Josefsson, Elisabet; Steinkasserer, Alexander; Rudin, Anna

    2007-01-01

    CD14 is expressed on the cell surface of various antigen-presenting cells, and CD83 is a maturation marker for dendritic cells (DC). CD14 and CD83 are also present as soluble proteins, and both have immunoregulatory functions. We examined whether neonatal cord blood monocytes or DC released soluble CD14 (sCD14) or sCD83 when exposed to the commensal intestinal bacteria Clostridium perfringens, Staphylococcus aureus, Lactobacillus rhamnosus, Escherichia coli, and Bacteroides fragilis. We found...

  13. Attachment of oral bacteria to a basement-membrane-like matrix and to purified matrix proteins.

    OpenAIRE

    Winkler, J R; S. R. John; Kramer, R H; Hoover, C.I.; Murray, P A

    1987-01-01

    The purpose of this study was to investigate the adherence of oral bacteria to an in vitro basement-membrane-like matrix and to selected individual macromolecular constituents of this matrix. Radiolabeled bacteria were incubated with basement-membrane-like matrices isolated from PF HR-9 cells. Bacteroides gingivalis 33277, Fusobacterium nucleatum FN-2, and Actinobacillus actinomycetemcomitans GA3(A) bound to the matrix in the range of 44 to 70%, considerably higher than the ranges of A. actin...

  14. Degradation of chondroitin sulfate by the gut microbiota of Chinese individuals.

    Science.gov (United States)

    Shang, Qingsen; Yin, Yeshi; Zhu, Liying; Li, Guoyun; Yu, Guangli; Wang, Xin

    2016-05-01

    Oral preparations of chondroitin sulfate (CS) have long been used as anti-osteoarthritis (anti-OA) drugs. However, little is known about the degradation of CS by human gut microbiota. In the present study, degradation profiles of CSA (the main constituent of CS drugs) by the human gut microbiota from six healthy subjects were investigated. Each individual's microbiota had differing degradation activities, but ΔUA-GalNAc4S was the end product in all cases. To elucidate the mechanisms underlying this phenomenon, different CSA-degrading bacteria were isolated from each individual's microbiota and tested for CSA degradation. In addition to Bacteroides thetaiotaomicron J1, Bacteroides thetaiotaomicron 82 and Bacteroides ovatus E3, a new CSA-degrading bacterium, Clostridium hathewayi R4, was isolated and characterized. Interestingly, at least two different CSA-degrading species were identified from each individual's gut microbiota. Predictably, these functional bacteria also had differing degradation rates, but still generated the same end product, ΔUA-GalNAc4S. In addition, the human fecal isolates produced different degradation profiles for CSC, CSD, and CSE, suggesting that CS could be readily metabolized to varying extents by diverse microbial consortiums, which may help to explain the poor bioavailability and unequal efficacy of CS among individuals in OA treatment. PMID:26800901

  15. Effect of oligosaccharides on the adhesion of gut bacteria to human HT-29 cells.

    Science.gov (United States)

    Altamimi, M; Abdelhay, O; Rastall, R A

    2016-06-01

    The influence of five oligosaccharides (cellobiose, stachyose, raffinose, lactulose and chito-oligosaccharides) on the adhesion of eight gut bacteria (Bifidobacterium bifidum ATCC 29521, Bacteroides thetaiotaomicron ATCC 29148D-5, Clostridium leptum ATCC 29065, Blautia coccoides ATCC 29236, Faecalibacterium prausnitzii ATCC 27766, Bacteroides fragilis ATCC 23745, Clostridium difficile ATCC 43255 and Lactobacillus casei ATCC 393) to mucous secreting and non-mucous secreting HT-29 human epithelial cells, was investigated. In pure culture, the bacteria showed variations in their ability to adhere to epithelial cells. The effect of oligosaccharides diminished adhesion and the presence of mucus played a major factor in adhesion, likely due to high adhesiveness to mucins present in the native human mucus layer covering the whole cell surface. However, clostridia displayed almost the same level of adhesion either with or without mucus being present. Bl. coccoides adhesion was decreased by stachyose and cellobiose in non-mucus-secreting cells in pure culture, while in mixed faecal culture cellobiose displayed the highest antiadhesive activity with an overall average of 65% inhibition amongst tested oligomers and lactulose displayed the lowest with an average of 47.4%. Bifidobacteria, Bacteroides, lactobacilli and clostridia were inhibited within the following ranges 47-78%, 32-65%, 11.7-58% and 64-85% respectively. This means that clostridia were the most strongly influenced members of the microflora amongst the bacterial groups tested in mixed culture. In conclusion, introducing oligosaccharides which are candidate prebiotics into pure or mixed cultures has affected bacterial adhesion. PMID:27018325

  16. In vitro fermentation of alginate and its derivatives by human gut microbiota.

    Science.gov (United States)

    Li, Miaomiao; Li, Guangsheng; Shang, Qingsen; Chen, Xiuxia; Liu, Wei; Pi, Xiong'e; Zhu, Liying; Yin, Yeshi; Yu, Guangli; Wang, Xin

    2016-06-01

    Alginate (Alg) has a long history as a food ingredient in East Asia. However, the human gut microbes responsible for the degradation of alginate and its derivatives have not been fully understood yet. Here, we report that alginate and the low molecular polymer derivatives of mannuronic acid oligosaccharides (MO) and guluronic acid oligosaccharides (GO) can be completely degraded and utilized at various rates by fecal microbiota obtained from six Chinese individuals. However, the derivative of propylene glycol alginate sodium sulfate (PSS) was not hydrolyzed. The bacteria having a pronounced ability to degrade Alg, MO and GO were isolated from human fecal samples and were identified as Bacteroides ovatus, Bacteroides xylanisolvens, and Bacteroides thetaiotaomicron. Alg, MO and GO can increase the production level of short chain fatty acids (SCFA), but GO generates the highest level of SCFA. Our data suggest that alginate and its derivatives could be degraded by specific bacteria in the human gut, providing the basis for the impacts of alginate and its derivates as special food additives on human health. PMID:26891629

  17. The evolution of cooperation within the gut microbiota.

    Science.gov (United States)

    Rakoff-Nahoum, Seth; Foster, Kevin R; Comstock, Laurie E

    2016-05-12

    Cooperative phenotypes are considered central to the functioning of microbial communities in many contexts, including communication via quorum sensing, biofilm formation, antibiotic resistance, and pathogenesis. The human intestine houses a dense and diverse microbial community critical to health, yet we know little about cooperation within this important ecosystem. Here we test experimentally for evolved cooperation within the Bacteroidales, the dominant Gram-negative bacteria of the human intestine. We show that during growth on certain dietary polysaccharides, the model member Bacteroides thetaiotaomicron exhibits only limited cooperation. Although this organism digests these polysaccharides extracellularly, mutants lacking this ability are outcompeted. In contrast, we discovered a dedicated cross-feeding enzyme system in the prominent gut symbiont Bacteroides ovatus, which digests polysaccharide at a cost to itself but at a benefit to another species. Using in vitro systems and gnotobiotic mouse colonization models, we find that extracellular digestion of inulin increases the fitness of B. ovatus owing to reciprocal benefits when it feeds other gut species such as Bacteroides vulgatus. This is a rare example of naturally-evolved cooperation between microbial species. Our study reveals both the complexity and importance of cooperative phenotypes within the mammalian intestinal microbiota. PMID:27111508

  18. Microbial source markers assessment in the Bogotá River basin (Colombia).

    Science.gov (United States)

    Venegas, Camilo; Diez, Hugo; Blanch, Anicet R; Jofre, Juan; Campos, Claudia

    2015-09-01

    The microbiological indicators traditionally used to assess fecal contamination are insufficient to identify the source. The aim of this study was to detect microbial markers to identify the source of fecal pollution in the Bogotá River (Colombia). For this, we determined non-discriminating indicators such as Escherichia coli, somatic coliphages and phages infecting strain RYC2056 of Bacteroides, and potential source tracking markers as phages infecting strains GA17, HB13, and CA8 of Bacteroides, sorbitol-fermenting bifidobacteria, and molecular markers of Bifidobacterium adolescentis, Bifiodobacterium dentium, and Bacteroidetes in raw municipal wastewaters, slaughterhouse wastewaters, and the Bogotá River. Bacteriophages infecting Bacteroides strain GA17 and the molecular markers identified the wastewater sources. In contrast, sorbitol-fermenting bifidobacteria failed regarding specificity. In the Bogotá River, phages infecting strain GA17 were detected in all samples downstream of Bogotá, whereas they should be concentrated from 1 l samples in upstream samples containing less than 10(3) E. coli/100 ml to be detected. In the river water, the fraction of positive detections of molecular markers was lower than that of phages infecting strain GA17. The ratio SOMCPH/GA17PH was shown also to be a good marker. These results provide information that will allow focusing measures for sanitation of the Bogotá River. PMID:26322765

  19. 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.

  20. Fermentation characteristics ofMegasphaera elsdeniiJ6 derived from pig feces on different lactate isomers

    Institute of Scientific and Technical Information of China (English)

    JIANG Xiao-lin; SU Yong; ZHU Wei-yun

    2016-01-01

    D-Lactate-utilizing bacteria play important roles in maintaining the balance of gut lactate; however, studies on gut D-lactate-uti-lizing bacteria have been limited. This study aimed to isolate and identify D-lactate-utilizing bacteria from pig gut using the Hungate rol-tube method, and to investigate their metabolic characteristicsin vitro. Six different anaerobes were isolated from pig feces, which were identiifed as related toBacteroides fragilis, Bacteroides acidifaciens,Veilonela denticariosi, Veilonela caviae,Bacteroides uniformis, andMegasphaera elsdenibased on the 16S rRNA gene sequences. Al strains had a signiifcant ability to utilize D-lactate, which was concluded afterin vitro fermentation with 25 mmol L–1 D-lactate as the primary carbon source. Of al 6 strains,M. elsdeniJ6 showed the highest efifciency of D-lactate utilization and produced a higher ratio of butyrate in total short chain fatty acids (SCFAs). Thus, thein vitro fermentation characteristics of this strain in D-, L-, and DL-lactate mixtures (D-lactate:L-lactate=1:1 or 1:2) were further studied. The results showed that M. elsdeni J6 preferred utilizing D-lactate, and produced more SCFA when using D-lactate as the primary carbon source. The ifndings suggest that the administration of D-lactate-utilizing bacteria such asM. elsdeni J6 may have a potential advantage in the aleviation of D-lactic acidosis in the animal gut.

  1. Evidence for extraintestinal growth of bacteroidales originating from poultry litter.

    Science.gov (United States)

    Weidhaas, Jennifer; Mantha, Sirisha; Hair, Elliott; Nayak, Bina; Harwood, Valerie J

    2015-01-01

    Water quality monitoring techniques that target microorganisms in the order Bacteroidales are potential alternatives to conventional methods for detection of fecal indicator bacteria. Bacteroidales and members of the genus Bacteroides have been the focus of microbial source tracking (MST) investigations for discriminating sources of fecal pollution (e.g., human or cattle feces) in environmental waters. For accurate source apportionment to occur, one needs to understand both the abundance of Bacteroides in host feces and the survival of these host-associated microbial markers after deposition in the environment. Studies were undertaken to evaluate the abundance, persistence, and potential for growth of Bacteroidales originating from poultry litter under oxic and anoxic environmental conditions. Bacteroidales abundance, as determined by quantitative PCR (qPCR) with GenBac primers and probe, increased 2 to 5 log gene copies ml(-1) and 2 log gene copies g litter(-1) under most conditions during incubation of poultry litter in a variety of laboratory microcosm and field mesocosm studies. DNA sequencing of the Bacteroidales organisms in the litter identified taxa with sequences corresponding exactly to the GenBac primer and probe sequences and that were closely related to Bacteroides uniformis, B. ovatus, and B. vulgatus. These results suggest that MST studies using qPCR methods targeting Bacteroidales in watersheds that are affected by poultry litter should be interpreted cautiously. Growth of Bacteroidales originating from poultry litter in environmental waters may occur while Bacteroidales growth from other fecal sources declines, thus confounding the interpretation of MST results. PMID:25326306

  2. Proline auxotrophy in Sinorhizobium meliloti results in a plant-specific symbiotic phenotype.

    Science.gov (United States)

    diCenzo, George C; Zamani, Maryam; Cowie, Alison; Finan, Turlough M

    2015-12-01

    In order to effectively manipulate rhizobium-legume symbioses for our benefit, it is crucial to first gain a complete understanding of the underlying genetics and metabolism. Studies with rhizobium auxotrophs have provided insight into the requirement for amino acid biosynthesis during the symbiosis; however, a paucity of available L-proline auxotrophs has limited our understanding of the role of L-proline biosynthesis. Here, we examined the symbiotic phenotypes of a recently described Sinorhizobium meliloti L-proline auxotroph. Proline auxotrophy was observed to result in a host-plant-specific phenotype. The S. meliloti auxotroph displayed reduced symbiotic capability with alfalfa (Medicago sativa) due to a decrease in nodule mass formed and therefore a reduction in nitrogen fixed per plant. However, the proline auxotroph formed nodules on white sweet clover (Melilotus alba) that failed to fix nitrogen. The rate of white sweet clover nodulation by the auxotroph was slightly delayed, but the final number of nodules per plant was not impacted. Examination of white sweet clover nodules by confocal microscopy and transmission electron microscopy revealed the presence of the S. meliloti proline auxotroph cells within the host legume cells, but few differentiated bacteroids were identified compared with the bacteroid-filled plant cells of WT nodules. Overall, these results indicated that L-proline biosynthesis is a general requirement for a fully effective nitrogen-fixing symbiosis, likely due to a transient requirement during bacteroid differentiation. PMID:26395514

  3. Development and testing of real-time PCR assays for determining fecal loading and source identification (cattle, human, etc.) in surface water and groundwater

    Science.gov (United States)

    McKay, L. D.; Layton, A.; Gentry, R.

    2004-12-01

    A multi-disciplinary group of researchers at the University of Tennessee is developing and testing a series of microbial assay methods based on real-time PCR to detect fecal bacterial concentrations and host sources in water samples. Real-time PCR is an enumeration technique based on the unique and conserved nucleic acid sequences present in all organisms. The first research task was development of an assay (AllBac) to detect total amount of Bacteroides, which represents up to 30 percent of fecal mass. Subsequent assays were developed to detect Bacteroides from cattle (BoBac) and humans (HuBac) using 16sRNA genes based on DNA sequences in the national GenBank, as well as sequences from local fecal samples. The assays potentially have significant advantages over conventional bacterial source tracking methods because: 1. unlike traditional enumeration methods, they do not require bacterial cultivation; 2. there are no known non-fecal sources of Bacteroides; 3. the assays are quantitative with results for total concentration and for each species expressed in mg/l; and 4. they show little regional variation within host species, meaning that they do not require development of extensive local gene libraries. The AllBac and BoBac assays have been used in a study of fecal contamination in a small rural watershed (Stock Creek) near Knoxville, TN, and have proven useful in identification of areas where cattle represent a significant fecal input and in development of BMPs. It is expected that these types of assays (and future assays for birds, hogs, etc.) could have broad applications in monitoring fecal impacts from Animal Feeding Operations, as well as from wildlife and human sources.

  4. Pleiotropic effects of a rel mutation on stress survival of Rhizobium etli CNPAF512

    Directory of Open Access Journals (Sweden)

    Beullens Serge

    2008-12-01

    Full Text Available Abstract Background The rel gene of Rhizobium etli (relRet, the nodulating endosymbiont of the common bean plant, determines the cellular level of the alarmone (pppGpp and was previously shown to affect free-living growth and symbiosis. Here, we demonstrate its role in cellular adaptation and survival in response to various stresses. Results Growth of the R. etli relRet mutant was strongly reduced or abolished in the presence of elevated NaCl levels or at 37°C, compared to the wild type. In addition, depending on the cell density, decreased survival of exponentially growing or stationary phase relRet mutant cells was obtained after H2O2, heat or NaCl shock compared to the wild-type strain. Survival of unstressed stationary phase cultures was differentially affected depending on the growth medium used. Colony forming units (CFU of relRet mutant cultures continuously decreased in minimal medium supplemented with succinate, whereas wild-type cultures stabilised at higher CFU levels. Microscopic examination of stationary phase cells indicated that the relRet mutant was unable to reach the typical coccoid morphology of the wild type in stationary phase cultures. Assessment of stress resistance of re-isolated bacteroids showed increased sensitivity of the relRet mutant to H2O2 and a slightly increased resistance to elevated temperature (45°C or NaCl shock, compared to wild-type bacteroids. Conclusion The relRet gene is an important factor in regulating rhizobial physiology, during free-living growth as well as in symbiotic conditions. Additionally, differential responses to several stresses applied to bacteroids and free-living exponential or stationary phase cells point to essential physiological differences between the different states.

  5. Microbial Source Tracking as a Tool for TMDL Development, Little Blue River in Independence, Missouri

    Science.gov (United States)

    Christensen, Eric D.; Bushon, Rebecca N.; Brady, Amie M.G.

    2013-01-01

    The Little Blue River in Jackson County, Missouri has been listed by the Missouri Department of Natural Resources as impaired by bacteria for the protection of aquatic life and contact recreation from urban point and nonpoint sources. The Clean Water Act requires that a total maximum daily load (TMDL) for Escherichia coli (E. coli) be developed. Over a 5-year period, 108 base-flow, 87 stormflow, 48 fecal source, and 12 sewage influent samples were collected and analyzed for E. coli and Bacteroides general and host-associated microbial source tracking (MST) genetic markers. Less than half of the main-stem base-flow samples exceeded the E. coli state standard, whereas, all of the stormflow samples exceeded the standard during the recreation season (April through October). Both E. coli and MST markers were detected more frequently and at higher concentrations in stormflow samples. Only 14 percent of samples with E. coli detections greater than the Missouri state standard of 206 colonies per 100 milliliters had the human-associated Bacteroides marker as the only identified marker; therefore, Little Blue River TMDL development may require a broader scope beyond the municipal separate storm sewer system if bacteria sources are to be identified and addressed. Fecal samples showed a greater specificity with the human-associated marker than the dog- or ruminant-associated Bacteroides markers; however, false positives were at least one order of magnitude lower than true positives. MST data may be a useful tool for identifying probable sources of contamination and directing TMDL strategies.

  6. The influence of non-steroidal anti-inflammatory drugs on the gut microbiome.

    Science.gov (United States)

    Rogers, M A M; Aronoff, D M

    2016-02-01

    The composition of the gut microbiome with the use of non-steroidal anti-inflammatory drugs (NSAIDs) has not been fully characterized. Drug use within the past 30 days was ascertained in 155 adults, and stool specimens were submitted for analysis. Area under the receiver operating characteristic curve (AUC) was calculated in logit models to distinguish the relative abundance of operational taxonomic units (OTUs) by medication class. The type of medication had a greater influence on the gut microbiome than the number of medications. NSAIDs were particularly associated with distinct microbial populations. Four OTUs (Prevotella species, Bacteroides species, family Ruminococcaceae, and Barnesiella species) discriminated aspirin users from those using no medication (AUC = 0.96; 95% CI 0.84-1.00). The microbiome profile of celecoxib users was similar to that of ibuprofen users, with both showing enrichment of Acidaminococcaceae and Enterobacteriaceae. Bacteria from families Propionibacteriaceae, Pseudomonadaceae, Puniceicoccaceae and Rikenellaceae were more abundant in ibuprofen users than in controls or naproxen users. Bacteroides species and Erysipelotrichaceae species discriminated individuals using NSAIDs plus proton-pump inhibitors from those using NSAIDs alone (AUC = 0.96; 95% CI 0.87-1.00). Bacteroides species and a bacterium of family Ruminococcaceae discriminated individuals using NSAIDs in combination with antidepressants and laxatives from those using NSAIDs alone (AUC = 0.98; 95% CI 0.93-1.00). In conclusion, bacteria in the gastrointestinal tract reflect the combinations of medications that people ingest. The bacterial composition of the gut varied with the type of NSAID ingested. PMID:26482265

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

    Science.gov (United States)

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

    2014-10-01

    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, clindamycin, penicillin, ampicillin, meropenem, ciprofloxacin, and amdinocillin) against a CTX-M-15-producing E. coli sequence type 131 (ST131) isolate with a fluoroquinolone resistance phenotype. Mice (8 per group) were orogastrically administered 0.25 ml saline with 10(8) CFU/ml E. coli ST131. On that same 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 0.95), nor did they suppress Bacteroides or Gram-positive organisms. The results showed that antimicrobials both with and without an impact on Gram-negative anaerobes can select for ESBL-producing E. coli, indicating that not only Gram-negative anaerobes have a role in upholding colonization resistance. Other, so-far-unknown bacterial populations must be of importance for preventing colonization by incoming E. coli. PMID:25092712

  8. Higher blood glucose level associated with body mass index and gut microbiota in elderly people

    Science.gov (United States)

    Sepp, Epp; Kolk, Helgi; Lõivukene, Krista; Mikelsaar, Marika

    2014-01-01

    Background Some dominant bacterial divisions of the intestines have been linked to metabolic diseases such as overweight and diabetes. Objective A pilot study aimed to evaluate the relations between the culturable intestinal bacteria with body mass index (BMI) and some principal cellular and metabolic markers of blood in people older than 65. Design Altogether 38 generally healthy elderly people were recruited: ambulatory (n=19) and orthopedic surgery (n=19). Questionnaires on general health, anthropometric measurements, routine clinical and laboratory data, and quantitative composition of cultivable gut microbiota were performed. Results Blood glucose level was positively correlated with BMI (r=0.402; p=0.014). Higher blood glucose level had negative correlation with relative share of intestinal anaerobic bacteria such as bacteroides (r=−0.434; p=0.0076) and gram-positive anaerobic cocci (r=−0.364; p=0.027). In contrast, the relative share of bifidobacteria (r=0.383; p=0.019) and staphylococci (r=0.433; p=0.008) was positively correlated to blood glucose level. In elderly people, a higher blood glucose concentration was predicted by the reduction of the anaerobes’ proportion (adj. sex, age, and BMI R2=0.192, p=0.028) and that of Bacteroides sp. (adj. R2=0.309, p=0.016). Conclusion A tight interplay between increased BMI, level of blood glucose, and the reduced proportion of cultivable bacteroides is taking place in the gut microbiota of elderly people. PMID:24936169

  9. Higher blood glucose level associated with body mass index and gut microbiota in elderly people

    Directory of Open Access Journals (Sweden)

    Epp Sepp

    2014-06-01

    Full Text Available Background: Some dominant bacterial divisions of the intestines have been linked to metabolic diseases such as overweight and diabetes. Objective: A pilot study aimed to evaluate the relations between the culturable intestinal bacteria with body mass index (BMI and some principal cellular and metabolic markers of blood in people older than 65. Design: Altogether 38 generally healthy elderly people were recruited: ambulatory (n=19 and orthopedic surgery (n=19. Questionnaires on general health, anthropometric measurements, routine clinical and laboratory data, and quantitative composition of cultivable gut microbiota were performed. Results: Blood glucose level was positively correlated with BMI (r=0.402; p=0.014. Higher blood glucose level had negative correlation with relative share of intestinal anaerobic bacteria such as bacteroides (r=−0.434; p=0.0076 and gram-positive anaerobic cocci (r=−0.364; p=0.027. In contrast, the relative share of bifidobacteria (r=0.383; p=0.019 and staphylococci (r=0.433; p=0.008 was positively correlated to blood glucose level. In elderly people, a higher blood glucose concentration was predicted by the reduction of the anaerobes’ proportion (adj. sex, age, and BMI R2=0.192, p=0.028 and that of Bacteroides sp. (adj. R2=0.309, p=0.016. Conclusion: A tight interplay between increased BMI, level of blood glucose, and the reduced proportion of cultivable bacteroides is taking place in the gut microbiota of elderly people.

  10. TNFR2 Deficiency Acts in Concert with Gut Microbiota To Precipitate Spontaneous Sex-Biased Central Nervous System Demyelinating Autoimmune Disease.

    Science.gov (United States)

    Miller, Patrick G; Bonn, Michael B; Franklin, Craig L; Ericsson, Aaron C; McKarns, Susan C

    2015-11-15

    TNF-α antagonists provide benefit to patients with inflammatory autoimmune disorders such as Crohn's disease, rheumatoid arthritis, and ankylosing spondylitis. However, TNF antagonism unexplainably exacerbates CNS autoimmunity, including multiple sclerosis and neuromyelitis optica. The underlying mechanisms remain enigmatic. We demonstrate that TNFR2 deficiency results in female-biased spontaneous autoimmune CNS demyelination in myelin oligodendrocyte glycoprotein-specific 2D2 TCR transgenic mice. Disease in TNFR2(-/-) 2D2 mice was associated with CNS infiltration of T and B cells as well as increased production of myelin oligodendrocyte glycoprotein-specific IL-17, IFN-γ, and IgG2b. Attenuated disease in TNF(-/-) 2D2 mice relative to TNFR2(-/-) 2D2 mice identified distinctive roles for TNFR1 and TNFR2. Oral antibiotic treatment eliminated spontaneous autoimmunity in TNFR2(-/-) 2D2 mice to suggest role for gut microbiota. Illumina sequencing of fecal 16S rRNA identified a distinct microbiota profile in male TNFR2(-/-) 2D2 that was associated with disease protection. Akkermansia muciniphila, Sutterella sp., Oscillospira sp., Bacteroides acidifaciens, and Anaeroplasma sp. were selectively more abundant in male TNFR2(-/-) 2D2 mice. In contrast, Bacteroides sp., Bacteroides uniformis, and Parabacteroides sp. were more abundant in affected female TNFR2(-/-) 2D2 mice, suggesting a role in disease causation. Overall, TNFR2 blockade appears to disrupt commensal bacteria-host immune symbiosis to reveal autoimmune demyelination in genetically susceptible mice. Under this paradigm, microbes likely contribute to an individual's response to anti-TNF therapy. This model provides a foundation for host immune-microbiota-directed measures for the prevention and treatment of CNS-demyelinating autoimmune disorders. PMID:26475926

  11. Gut bacteria alteration in obese people and its relationship with gene polymorphism

    Institute of Scientific and Technical Information of China (English)

    Hao-Jiang Zuo; Zhi-Mei Xie; Wei-Wei Zhang; Yong-Ru Li; Wei Wang; Xiao-Bei Ding; Xiao-Fang Pei

    2011-01-01

    AIM:To investigate the differences in cultivable gut bacteria and peroxisome proliferator-activated receptor γ2 (PPAR-γ2 ) gene Pro12Ala variation in obese and normal-weight Chinese people. METHODS:Using culture methods,the amounts of Escherichia coli ,Enterococci ,Bacteroides ,Lactobacilli ,Bifidobacteria and Clostridium perfringens (C.perfringens ) in the feces of 52 obese participants [body mass index (BMI):≥ 28 kg/m2] and 52 participants of normalweight (BMI:18.5-24 kg/m2) were obtained.Study participants completed comprehensive questionnaires and underwent clinical laboratory tests.The polymerase chain reaction-restriction fragment length polymorphism (PCR-PFLP) assay was used to analyze PPAR-γ2 gene Pro12Ala variation. RESULTS:The obese group exhibited a lower amount of C.perfringens (6.54 ± 0.65 vs 6.94 ± 0.57,P = 0.001) and Bacteroides (9.81 ± 0.58 vs 10.06 ± 0.39,P = 0.012) than their normal-weight counterparts.No major differences were observed in Pro12Ala genotype distribution between the two groups; however,obese individuals with a Pro/Ala genotype had a significantly lower level of Bacteroides (9.45 ± 0.62 vs 9.93 ± 0.51,P = 0.027) than those with a Pro/Pro genotype.In addition, the obese group demonstrated a higher stool frequency (U = 975,P < 0.001) and a looser stool (U = 1062,P = 0.015) than the normal-weight group. CONCLUSION:Our results indicated interactions among cultivable gut flora,host genetic factors and obese phenotype and this might be helpful for obesity prevention.

  12. Rhizobial Diversity and Nodulation Characteristics of the Extremely Promiscuous Legume Sophora flavescens.

    Science.gov (United States)

    Jiao, Yin Shan; Liu, Yuan Hui; Yan, Hui; Wang, En Tao; Tian, Chang Fu; Chen, Wen Xin; Guo, Bao Lin; Chen, Wen Feng

    2015-12-01

    In present study, we report our extensive survey on the diversity and biogeography of rhizobia associated with Sophora flavescens, a sophocarpidine (matrine)-containing medicinal legume. We additionally investigated the cross nodulation, infection pattern, light and electron microscopies of root nodule sections of S. flavescens infected by various rhizobia. Seventeen genospecies of rhizobia belonging to five genera with seven types of symbiotic nodC genes were found to nodulate S. flavescens in natural soils. In the cross-nodulation tests, most representative rhizobia in class α-Proteobacteria, whose host plants belong to different cross-nodulation groups, form effective indeterminate nodules, while representative rhizobia in class β-Proteobacteria form ineffective nodules on S. flavescens. Highly host-specific biovars of Rhizobium leguminosarum (bv. trifolii and bv. viciae) and Rhizobium etli bv. phaseoli could establish symbioses with S. flavescens, providing further evidence that S. flavescens is an extremely promiscuous legume and it does not have strict selectivity on either the symbiotic genes or the species-determining housekeeping genes of rhizobia. Root-hair infection is found as the pattern that rhizobia have gained entry into the curled root hairs. Electron microscopies of ultra-thin sections of S. flavescens root nodules formed by different rhizobia show that the bacteroids are regular or irregular rod shape and nonswollen types. Some bacteroids contain poly-β-hydroxybutyrate (PHB), while others do not, indicating the synthesis of PHB in bacteroids is rhizobia-dependent. The extremely promiscuous symbiosis between S. flavescens and different rhizobia provide us a basis for future studies aimed at understanding the molecular interactions of rhizobia and legumes. PMID:26389798

  13. Phylogenetic analysis of bacteria in sea ice brine sampled from the Canada Basin, Arctic Ocean

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    Bacterial diversity in sea ice brine samples which collected from four stations located at the Canada Basin, Arctic Ocean was analyzed by PCR-DGGE. Twenty-three 16S rDNA sequences of bacteria obtained from DGGE bands were cloned and sequenced. Phylogenetic analysis clustered these sequences within γ-proteobacteria, Cytophaga-Flexibacter-Bacteroides (CFB) group, Firmicutes and Actinobacteria. The phylotype of Pseudoalteromonas in the γ-proteobacteria was predominant and members of the CFB group and γ-proteobacteria were highly abundant in studied sea ice brine samples.

  14. Dicty_cDB: Contig-U15333-1 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available Name: Full=NADP-specific glutamate dehydrogenase; ... 74 8e-25 CP000115_2272( CP000115 |pid:none) Nitrobacter winogra...3347( CR626927 |pid:none) Bacteroides fragilis NCTC 9343,... 75 1e-26 ( P94316 ) RecName: Full=NAD-specific glutamate dehydrog... yezoensis strain TU-1 glu... 100 8e-26 AI1503( AI1503 ) NADP-specific glutamate dehydrog...Name: Full=NAD-specific glutamate dehydrogenase; ... 117 6e-53 AE016877_1361( AE016877 |pid:no...Name: Full=NAD-specific glutamate dehydrogenase; ... 117 2e-52 A

  15. Estudio comparativo de la acción antimicrobiana de diversos fondos cavitarios empleados en Odontología conservadora

    OpenAIRE

    Pumarola Suñé, José; Espías Gómez, Ángel F. (Ángel Fortunato); Canalda Sahli, Carlos

    1989-01-01

    La existencia de diversos fondos cavitarios, nos ha conducido a la comparación de su acción inhibidora del crecimiento microbiano. Para ellos se han tenido en cuenta los siguientes fondos cavitarios: Life, Dycal. 11, Calcipulpe, Hidróxido cálcico puro y Cavitec; habiendo testado las siguientes especies bacterianas: Veillonella parvula, Bacteroides'fragilis, Peptococcus s.p., Staphylococcus aureus y Streptococcus B hemolítico. Los resultados obtenidos en esta investigación demuestran el mayor ...

  16. Dicty_cDB: VSH274 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available raspanin tspC; 173 4e-42 AE015928_2029( AE015928 |pid:none) Bacteroides thetaiotaomicron VP... 39 0.12 ...sdlcpkdgdkikyeghycgealsdqfsskiyavgaaglaigi ielvailfslfliiricrsprtrsxasilnk*ikqnk*...ces producing significant alignments: (bits) Value N ( AU267180 ) Dictyostelium discoideum vegetative cDNA c...7 ) Dictyostelium discoideum vegetative cDNA clone:VS... 1098 0.0 2 ( C84714 ) Di... Dictyostelium discoideum vegetative cDNA clone:VS... 658 0.0 2 ( C90221 ) Dictyostelium discoideum slug cDN

  17. Novel aerobic tetracycline resistance gene that chemically modifies tetracycline.

    OpenAIRE

    Speer, B S; Salyers, A A

    1989-01-01

    A tetracycline resistance gene that was found originally on the Bacteroides plasmid pBF4 confers resistance on Escherichia coli but only when cells are growing aerobically. When E. coli EM24 carrying this aerobic tetracycline resistance (*Tcr) gene is grown in medium containing tetracycline, the resulting spent medium is no longer toxic to tetracycline-sensitive (Tcs) E. coli EM24 (B.S. Speer and A.A. Salyers, J. Bacteriol. 170: 1423-1429, 1988). To determine whether the *Tcr gene product mod...

  18. The Infant Gut Microbiome: Evidence for Obesity Risk and Dietary Intervention

    Directory of Open Access Journals (Sweden)

    Petya T. Koleva

    2015-03-01

    Full Text Available Increasing globally, particularly in children, obesity is a serious public health issue and risk factor for overweight and metabolic disease in later life. Both in experimental animal and human studies, advances in gene sequencing technologies have yielded intriguing possibilities for the role of the gut microbiome in later development of overweight status. Before translating study findings into practice, we must first reconcile inconsistencies between animal experimentation, and human adult and infant studies. Recent evidence for associations with gut microbiota and infant weight gain or child weight status, implicate Bacteroides and Lactobacillus species. Dietary manipulation with human milk and pre/probiotic formulations holds promise for preventing obesity.

  19. Genes for a microaerobically induced oxidase complex in Bradyrhizobium japonicum are essential for a nitrogen-fixing endosymbiosis.

    OpenAIRE

    Preisig, O; Anthamatten, D; Hennecke, H

    1993-01-01

    We report the discovery of a Bradyrhizobium japonicum gene cluster (fixNOQP) in which mutations resulted in defective soybean root-nodule bacteroid development and symbiotic nitrogen fixation. The predicted, DNA-derived protein sequences suggested that FixN is a heme b and copper-binding oxidase subunit, FixO a monoheme cytochrome c, FixQ a polypeptide of 54 amino acids, and FixP a diheme cytochrome c and that they are all membrane-bound. The isolation and analysis of membrane proteins from B...

  20. Complete genome sequence of Croceibacter bacteriophage P2559S.

    Science.gov (United States)

    Kang, Ilnam; Kang, Dongmin; Cho, Jang-Cheon

    2012-08-01

    Croceibacter atlanticus HTCC2559(T), a marine bacterium isolated from the Sargasso Sea, is a phylogenetically unique member of the family Flavobacteriaceae. Strain HTCC2559(T) possesses genes related to interaction with primary producers, which makes studies on bacteriophages infecting the strain interesting. Here we report the genome sequence of bacteriophage P2559S, which was isolated off the coast of the Republic of Korea and lytically infects HTCC2559(T). Many genes predicted in the P2559S genome had their homologs in Bacteroides phages. PMID:22843867

  1. The Effect of Lactulose on the Survival of Lactobacillus rhamnosus in the Simulator of the Human Intestinal Microbial Ecosystem (SHIME) and in vivo

    OpenAIRE

    Kontula, Pia; Nollet, Lode; Saarela, Maria; Vilpponen-Salmela, Terttu; Verstraete, Willy; Mattila-Sandholm, Tiina; von Wright, Atte

    2011-01-01

    The effect of lactulose on the survival of Lactobacillus rhamnosus VTT E-97800 and on the colon microbiota and its metabolic activity was studied using the Simulator of the Human Intestinal Microbial Ecosystem (SHIME) model. L. rhamnosus VTT E-97800 and lactulose together enhanced the production of butyric acid and decreased ammonium concentration in the model. The numbers of Bacteroides were observed to decrease 2.5–2.0 log10 cfu:ml during the SHIME experiment. In the subsequent in viv...

  2. Intracellular pH of acid-tolerant ruminal bacteria.

    OpenAIRE

    Russell, J B

    1991-01-01

    Acid-tolerant ruminal bacteria (Bacteroides ruminicola B1(4), Selenomonas ruminantium HD4, Streptococcus bovis JB1, Megasphaera elsdenii B159, and strain F) allowed their intracellular pH to decline as a function of extracellular pH and did not generate a large pH gradient across the cell membrane until the extracellular pH was low (less than 5.2). This decline in intracellular pH prevented an accumulation of volatile fatty acid anions inside the cells.

  3. Characterization of the bacterial community associated with body wall lesions of Tripneustes gratilla (Echinoidea) using culture-independent methods.

    Science.gov (United States)

    Becker, Pierre T; Gillan, David C; Eeckhaut, Igor

    2009-02-01

    The bacterial community associated with skin lesions of the sea urchin Tripneustes gratilla was investigated using 16S ribosomal RNA gene cloning and fluorescent in situ hybridization (FISH). All clones were classified in the Alphaproteobacteria, Gammaproteobacteria and Cytophaga-Flexibacter-Bacteroides (CFB) bacteria. Most of the Alphaproteobacteria were related to the Roseobacter lineage and to bacteria implicated in marine diseases. The majority of the Gammaproteobacteria were identified as Vibrio while CFB represented only 9% of the total clones. FISH analyses showed that Alphaproteobacteria, CFB bacteria and Gammaproteobacteria accounted respectively for 43%, 38% and 19% of the DAPI counts. The importance of the methods used is emphasized. PMID:19041326

  4. AcEST: BP919832 [AcEST

    Lifescience Database Archive (English)

    Full Text Available 8025|PUR7_ARATH Phosphoribosylaminoimidazole-succinocarboxamide synthase, chloroplastic OS=Arabidopsis thaliana Align leng...dazole-succinocarboxamide synthase OS=Bacteroides fragilis GN=purC PE=3 SV=1 Length = 314 Score...UR3|A7NUR3_VITVI Phosphoribosylaminoimidazole-succinocarboxamide synthase OS=Vitis vinifera GN=GSVIVT00015149001 PE=3 SV=1 Leng...dazole-succinocarboxamide synthase, chloroplastic OS=Arabidopsis thaliana GN=PUR7 PE=2 SV=2 Leng...TELAWRYIFLYETITGSRIDIIPTQ 390 >sp|Q07463|PUR7_VIGAC Phosphoribosylaminoimidazole-succinocarboxamide synthase, chloroplastic (Fra

  5. Pathogenicity of enterococci in a rat model of fecal peritonitis.

    Science.gov (United States)

    Matlow, A G; Bohnen, J M; Nohr, C; Christou, N; Meakins, J

    1989-07-01

    The pathogenicity of enterococci in intraabdominal sepsis has not been clarified. Therefore, fecal-type peritonitis was induced in rats by intraperitoneal injection of barium sulfate along with a bacterial inoculum consisting of Escherichia coli, Bacteroides fragilis, and Clostridium perfringens with or without Streptococcus faecalis. Mortality at 19 d and characteristics of intraabdominal abscesses in survivors at 19 d were analyzed. The presence of S. faecalis in the original inoculum was significantly associated with death or large (greater than 20 mm) abscess formation when these two end points were examined together. S. faecalis may synergize with other bacteria in intraabdominal sepsis to augment morbidity and possibly mortality. PMID:2543707

  6. [Changes in sensitivity of clinical strains of bacteria to dioxidine from 1984 to 1988].

    Science.gov (United States)

    Bol'shakov, L V

    1990-09-01

    Dioxidine sensitivity of 7291 strains of aerobic bacteria and 163 strains of anaerobic bacteria was assayed with the disk diffusion method. The sensitivity of the aerobes was studied in the time course from 1984 to 1988. It was shown that during the 5-year period, the sensitivity of gram-positive bacteria to dioxidine gradually decreased. At the same time no increase in resistance of gram-negative organisms to dioxidine was observed. A high dioxidine sensitivity of obligate anaerobes, i.e. Clostridium spp., Bacteroides spp., Fusobacterium spp., anaerobic cocci and others was demonstrated. PMID:2275583

  7. Multilaboratory evaluation of an agar diffusion disk susceptibility test for rapidly growing anaerobic bacteria.

    Science.gov (United States)

    Barry, A L; Fuchs, P C; Gerlach, E H; Allen, S D; Acar, J F; Aldridge, K E; Bourgault, A M; Grimm, H; Hall, G S; Heizmann, W

    1990-01-01

    A multilaboratory collaborative study was undertaken to determine whether the anaerobic disk diffusion test of Horn et al. could be performed reproducibly and accurately. Tests with nine different antimicrobial disks were evaluated. Reproducibility of the agar diffusion disk method was similar to that of the reference agar dilution test procedure. The anaerobic disk diffusion procedure was found to be a potentially useful method for testing some antimicrobial agents against rapidly growing anaerobes belonging to the Bacteroides fragilis group. These promising results warrant further investigations and validations. PMID:2406872

  8. Dicty_cDB: Contig-U08276-1 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available s vulgatus ATCC 8482,... 68 5e-10 CP000937_1762( CP000937 |pid:none) Francisella philomiragia subsp.... 68 5...ncisella philomiragia subsp.... 68 7e-10 CP000387_341( CP000387 |pid...:none) Bordetella bronchiseptica strain... 66 3e-09 AY184800_1( AY184800 |pid:none) Chlam...:none) Streptococcus uberis 0140J comp... 65 3e-09 AM902716_1980( AM902716 |pid:none) Bordetella petrii stra...5 6e-09 AE015928_2229( AE015928 |pid:none) Bacteroides thetaiotaomicron VP... 65 6e-09 BX640414_260( BX640414 |pid:none) Bordetella

  9. Dicty_cDB: Contig-U16398-1 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available protein W03G11.3 - Caenorhabditis ele... 171 2e-79 CR626927_1714( CR626927 |pid:none) Bacteroides fragilis N...r t... 44 2e-08 4 ( EY389259 ) CAXA7751.fwd CAXA Helobdella robusta Subtracted L... 52...istant snail (BS... 34 6e-06 4 ( EY366812 ) CAXA10925.fwd CAXA Helobdella robusta Subtracted ... 52 9e-06 3 ...( EY365585 ) CAXA10268.fwd CAXA Helobdella robusta Subtracted ... 52 9e-06 3 ( EY...377107 ) CAXA16539.fwd CAXA Helobdella robusta Subtracted ... 52 1e-05 3 ( EY371880 ) CAXA13699.fwd CAXA Helobdella robusta Subtra

  10. Dicty_cDB: Contig-U09190-1 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available 1 7e-11 FJ222876_1( FJ222876 |pid:none) Xylella fastidiosa strain E O1b ci... 71 7e-11 AP006841_3746( AP006841 |pid:none) Bacteroide...07 9 ( EY334963 ) CAWY6720.rev CAWY Helobdella robusta Subtracted E... 56 3e-07 2...*... 42 3e-07 8 ( EY334244 ) CAWY6237.fwd CAWY Helobdella robusta Subtracted E......smodium falciparum chromosome 12 clone 3D7, **... 44 1e-06 8 ( EY325895 ) CAWY11234.rev CAWY Helobdella robusta Subtra...cted ... 44 1e-06 4 ( EY382916 ) CAXA431.fwd CAXA Helobdella robusta Subtracted La... 64 1

  11. Dicty_cDB: Contig-U15792-1 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available baltica OS155, compl... 249 3e-64 AE014299_1859( AE014299 |pid:none) Shewanella oneidensis MR-1, com... 2... loihica PV-4, comple... 242 3e-62 CP000447_2708( CP000447 |pid:none) Shewanella frigidima... bronchiseptica strain ... 213 2e-53 BX640436_178( BX640436 |pid:none) Bordetella...s fragilis NCTC 9343,... 192 4e-47 AP006841_1611( AP006841 |pid:none) Bacteroides fragi...rensis subsp. novicida U112, comp... 52 0.069 1 ( CP000437 ) Francisella tularensis subsp. hola

  12. Dicty_cDB: Contig-U10300-1 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available ns ORS 2... 116 1e-24 BX640416_10( BX640416 |pid:none) Bordetella pertussis strain Toham... 114 ...:none) Gluconobacter oxydans 621H, com... 93 2e-17 CP000447_3010( CP000447 |pid:none) Shewanella frigid...00447_2198( CP000447 |pid:none) Shewanella frigidimarina NCIMB ... 75 4e-12 CP001103_1911( CP001103 |pid:non...:none) Yersinia pseudotuberculosis strain... 69 2e-10 AE017354_2270( AE017354 |pid:none) Legionella pneumophila...:none) Bacteroides fragilis YCH46 DNA,... 69 3e-10 AY306007_1( AY306007 |pid:none) Da

  13. Dicty_cDB: Contig-U15213-1 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available rochlorococcus marinus str. NAT... 95 4e-18 CP000937_1559( CP000937 |pid:none) Francisella philomiragi...:none) Methylobacterium nodulans ORS 2... 88 4e-16 AP006841_3263( AP006841 |pid:none) Bacteroides fragili...:none) Shewanella denitrificans OS217,... 105 4e-21 CP000115_205( CP000115 |pid:none) Nitrobacter winogra...:none) Lactobacillus gasseri ATCC 33323... 100 9e-20 AE014299_2458( AE014299 |pid:none) Shewanella oneide... sp. JS666, complete... 99 3e-19 AM902716_1733( AM902716 |pid:none) Bordetella petrii strain DSM 12... 99 3e

  14. A bacterial carbohydrate links innate and adaptive responses through Toll-like receptor 2

    OpenAIRE

    Wang, Qun; McLoughlin, Rachel M.; Cobb, Brian A; Charrel-Dennis, Marie; Zaleski, Kathleen J.; Golenbock, Douglas; Tzianabos, Arthur O.; Kasper, Dennis L.

    2006-01-01

    Commensalism is critical to a healthy Th1/Th2 cell balance. Polysaccharide A (PSA), which is produced by the intestinal commensal Bacteroides fragilis, activates CD4+ T cells, resulting in a Th1 response correcting the Th2 cell skew of germ-free mice. We identify Toll-like receptors as crucial to the convergence of innate and adaptive responses stimulated by PSA. Optimization of the Th1 cytokine interferon-γ in PSA-stimulated dendritic cell–CD4+ T cell co-cultures depends on both Toll-like re...

  15. 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 of the...

  16. Dicty_cDB: Contig-U12908-1 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available 0... 36 0.008 18 ( BX293980 ) Mycoplasma mycoides subsp. mycoides SC str. PG1, ..... 0.089 12 ( AC117070 ) Dictyostelium discoideum chromosome 2 map 2097701... 34 0.... 0.66 CR382139_551( CR382139 |pid:none) Debaryomyces hansenii strain CBS... 39 0.66 (Q9JIL8) RecName: Full=DNA repair pro...:none) Plasmodium falciparum MAL3P2, com... 36 3.3 AP006841_778( AP006841 |pid:none) Bacteroides fragilis YC...irnvfkvlitilvgsiiygtytnqfqpn piepfhltepigqtwlhslkdistnwyhiwsdsfkdlarikplsesqtmpars*itr

  17. Competition Among Rhizobium leguminosarum Strains for Nodulation of Lentils (Lens esculenta)

    OpenAIRE

    May, Sheila N.; Bohlool, B. Ben

    1983-01-01

    Thirty-one cultures of Rhizobium leguminosarum were screened for effectiveness (C2H2 reduction) on lentils (Lens esculenta). Fluorescent antibodies prepared against three of the most effective strains (Hawaii 5-0, Nitragin 92A3, and Nitragin 128A12) exhibited a high degree of strain specificity; the antibodies reacted strongly with their homologous rhizobia in culture and with bacteroids in nodules. They did not cross-react with one another, and only weakly with 5 of the 47 other R. leguminos...

  18. Genetic analysis of the Rhizobium meliloti bacA gene: functional interchangeability with the Escherichia coli sbmA gene and phenotypes of mutants.

    OpenAIRE

    Ichige, A; Walker, G C

    1997-01-01

    The Rhizobium meliloti bacA gene encodes a function that is essential for bacterial differentiation into bacteroids within plant cells in the symbiosis between R. meliloti and alfalfa. An Escherichia coli homolog of BacA, SbmA, is implicated in the uptake of microcin B17, microcin J25 (formerly microcin 25), and bleomycin. When expressed in E. coli with the lacZ promoter, the R. meliloti bacA gene was found to suppress all the known defects of E. coli sbmA mutants, namely, increased resistanc...

  19. Immunological evaluation of the entirely carbohydrate-based Thomsen-Friedenreich - PS B conjugate.

    Science.gov (United States)

    Trabbic, Kevin R; Bourgault, Jean-Paul; Shi, Mengchao; Clark, Matthew; Andreana, Peter R

    2016-04-01

    PS B, a naturally occurring CD4(+) T-cell simulating zwitterionic polysaccharide from Bacteroides fragilis ATCC 25285/NCTC 9343, was conjugated with aminooxy Thomsen Friedenreich (TF or T) [α-d-Gal-(1,3)-β-d-GalNAc-ONH2] tumor antigen. Immunization in Jax C57BL/6, followed by ELISA revealed IgM and IgG antibody TF specificity. FACS data noted preferential binding to TF-laced MCF-7 cells but not to HCT-116 cells. PMID:26958987

  20. 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.

  1. Dynamics of Gut Microbiota According to the Delivery Mode in Healthy Korean Infants.

    Science.gov (United States)

    Lee, Eun; Kim, Byoung Ju; Kang, Mi Jin; Choi, Kil Yong; Cho, Hyun Ju; Kim, Yeongho; Yang, Song I; Jung, Young Ho; Kim, Hyung Young; Seo, Ju Hee; Kwon, Ji Won; Kim, Hyo Bin; Lee, So Yeon; Hong, Soo Jong

    2016-09-01

    Microbial colonization of the infant gut is unstable and shows a wide range of diversity between individuals. Gut microbiota play an important role in the development of the immune system, and an imbalance in these organisms can affect health, including an increased risk of allergic diseases. Microbial colonization of young infants is affected by the delivery mode at birth and the consequent alterations of gut microbiota in early life affect the development of allergic diseases. We investigated the effects of the delivery mode on the temporal dynamics of gut microbiota in healthy Korean infants. Fecal samples were collected at 1-3 days, 1 month, and 6 months after birth in six healthy infants. Microbiota were characterized by 16S rRNA shotgun sequencing. At the first and third days of life, infants born by vaginal delivery showed a higher richness and diversity of gut microbiota compared with those born by cesarean section. However, these differences disappeared with age. The Bacteroides genus and Bacteroidetes phylum were abundant in infants born by vaginal delivery, whereas Bacilli and Clostridium g4 were increased in infants born by cesarean section. The Firmicutes phylum and Bacteroides genus showed convergent dynamics with age. This study demonstrated the effect of delivery mode on the dynamics of gut microbiota profiles in healthy Korean infants. PMID:27334787

  2. 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. PMID:26123782

  3. Detection of S-nitrosothiol and nitrosylated proteins in Arachis hypogaea functional nodule: response of the nitrogen fixing symbiont.

    Directory of Open Access Journals (Sweden)

    Debasis Maiti

    Full Text Available To detect the presence of NO, ROS and RNS in nodules of crack entry legumes, we used Arachis hypogaea functional nodule. The response of two cognate partner rhizobia was compared towards NO and GSNO using S. meliloti and Bradyrhizobium sp NC921001. ROS, NO, nitrosothiol and bacteroids were detected by fluorescence microscopy. Redox enzymes and thiol pools were detected biochemically. Nitrosothiols were found to be present but ROS and NO were absent in A. hypogaea nodule. A number of S-nitrosylated proteins were also detected. The total thiol pool and most of the redox enzymes were low in nodule cytosolic extract but these were found to be high in the partner microorganisms indicating partner rhizobia could protect the nodule environment against the nitrosothiols. Both S. meliloti and Bradyrhizobium sp NC921001 were found to contain GSNO reductase. Interestingly, there was a marked difference in growth pattern between S. meliloti and Bradyrhizobium sp in presence of sodium nitroprusside (SNP and S-nitrosoglutathione (GSNO. Bradyrhizobium sp was found to be much more tolerant to NO donor compounds than the S. meliloti. In contrast, S. meliloti showed resistance to GSNO but was sensitive to SNP. Together our data indicate that nodule environment of crack entry legumes is different than the nodules of infection mode entry in terms of NO, ROS and RNS. Based on our biochemical characterization, we propose that exchange of redox molecules and reactive chemical species is possible between the bacteroid and nodule compartment.

  4. Species-function relationships shape ecological properties of the human gut microbiome.

    Science.gov (United States)

    Vieira-Silva, Sara; Falony, Gwen; Darzi, Youssef; Lima-Mendez, Gipsi; Garcia Yunta, Roberto; Okuda, Shujiro; Vandeputte, Doris; Valles-Colomer, Mireia; Hildebrand, Falk; Chaffron, Samuel; Raes, Jeroen

    2016-01-01

    Despite recent progress, the organization and ecological properties of the intestinal microbial ecosystem remain under-investigated. Here, using a manually curated metabolic module framework for (meta-)genomic data analysis, we studied species-function relationships in gut microbial genomes and microbiomes. Half of gut-associated species were found to be generalists regarding overall substrate preference, but we observed significant genus-level metabolic diversification linked to bacterial life strategies. Within each genus, metabolic consistency varied significantly, being low in Firmicutes genera and higher in Bacteroides. Differentiation of fermentable substrate degradation potential contributed to metagenomic functional repertoire variation between individuals, with different enterotypes showing distinct saccharolytic/proteolytic/lipolytic profiles. Finally, we found that module-derived functional redundancy was reduced in the low-richness Bacteroides enterotype, potentially indicating a decreased resilience to perturbation, in line with its frequent association to dysbiosis. These results provide insights into the complex structure of gut microbiome-encoded metabolic properties and emphasize the importance of functional and ecological assessment of gut microbiome variation in clinical studies. PMID:27573110

  5. Dietary resistant dextrins positively modulate fecal and cecal microbiota composition in young rats.

    Science.gov (United States)

    Śliżewska, Katarzyna; Libudzisz, Zdzisława; Barczyńska, Renata; Kapuśniak, Janusz; Zduńczyk, Zenon; Juśkiewicz, Jerzy

    2015-01-01

    The objective of the present study was to demonstrate the effect of dietary resistant dextrins, as potential prebiotics, on the intestinal microflora of young rats. Enzyme-resistant dextrin, prepared by heating of potato starch in the presence of hydrochloric (0.1% dsb) and tartaric (40% dsb) acid at 130ºC for 2 h (CA-dextrin). The experiment was performed on 24 Wistar male rats at 3-wk of age, divided by analogues in three experimental groups (control, starch and dextrin). Analyses determined the overall bacterial counts and the counts of Lactobacillus, Bifidobacterium, Bacteroides and Clostridium strains within the feces and cecal contents of rats using fluorescence in situ hybridization method. CA-dextrin had no effect on primary growth indicators (body weight, body weight gain, dietary consumption) or the mass of the small intestine and the cecum, but dextrins caused a reduction in pH and the concentration of ammonia within the cecal contents. That supplementation of diet with resistant dextrins had a positive effect on composition of intestinal microflora in rats. It increased the counts of Bifidobacterium and Lactobacillus strains both in the feces and in the cecum. Moreover, it reduced the counts of Clostridium and Bacteroides strains. These results may suggest that resistant dextrins exerted a prebiotic-like effect in the large intestine. PMID:26610307

  6. 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.

  7. 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.

  8. The Modulatory Effect of Anthocyanins from Purple Sweet Potato on Human Intestinal Microbiota in Vitro.

    Science.gov (United States)

    Zhang, Xin; Yang, Yang; Wu, Zufang; Weng, Peifang

    2016-03-30

    In order to investigate the modulatory effect of purple sweet potato anthocyanins (PSPAs) on human intestinal microbiota, PSPAs were prepared by column chromatography and their influence on intestinal microbiota was analyzed by monitoring the bacterial populations and analyzing short-chain fatty acid (SCFA) concentrations at different time points. The numbers (log10 cell/mL) of Bifidobacterium and Lactobacillus/Enterococcus spp., Bacteroides-Prevotella, Clostridium histolyticum, and total bacteria after 24 h of culture in anaerobic fermentation broth containing PSPAs were 8.44 ± 0.02, 8.30 ± 0.01, 7.80 ± 0.03, 7.60 ± 0.03, and 9.00 ± 0.02, respectively, compared with 8.21 ± 0.03, 8.12 ± 0.02, 7.95 ± 0.02, 7.77 ± 0.02, and 9.01 ± 0.03, respectively, in the controls. The results showed that PSPAs induced the proliferation of Bifidobacterium and Lactobacillus/Enterococcus spp., inhibited the growth of Bacteroides-Prevotella and Clostridium histolyticum, and did not affect the total bacteria number. Total SCFA concentrations in the cultures with PSPAs were significantly higher than in the controls (P acids, which may exert a better effect on intestinal microecology, suggesting that PSPAs may have prebiotic-like activity by generating SCFAs and modulating the intestinal microbiota, contributing to improvements in human health. PMID:26975278

  9. Cultured representatives of two major phylogroups of human colonic Faecalibacterium prausnitzii can utilize pectin, uronic acids, and host-derived substrates for growth.

    Science.gov (United States)

    Lopez-Siles, Mireia; Khan, Tanweer M; Duncan, Sylvia H; Harmsen, Hermie J M; Garcia-Gil, L Jesús; Flint, Harry J

    2012-01-01

    Faecalibacterium prausnitzii is one of the most abundant commensal bacteria in the healthy human large intestine, but information on genetic diversity and substrate utilization is limited. Here, we examine the phylogeny, phenotypic characteristics, and influence of gut environmental factors on growth of F. prausnitzii strains isolated from healthy subjects. Phylogenetic analysis based on the 16S rRNA sequences indicated that the cultured strains were representative of F. prausnitzii sequences detected by direct analysis of fecal DNA and separated the available isolates into two phylogroups. Most F. prausnitzii strains tested grew well under anaerobic conditions on apple pectin. Furthermore, F. prausnitzii strains competed successfully in coculture with two other abundant pectin-utilizing species, Bacteroides thetaiotaomicron and Eubacterium eligens, with apple pectin as substrate, suggesting that this species makes a contribution to pectin fermentation in the colon. Many F. prausnitzii isolates were able to utilize uronic acids for growth, an ability previously thought to be confined to Bacteroides spp. among human colonic anaerobes. Most strains grew on N-acetylglucosamine, demonstrating an ability to utilize host-derived substrates. All strains tested were bile sensitive, showing at least 80% growth inhibition in the presence of 0.5 μg/ml bile salts, while inhibition at mildly acidic pH was strain dependent. These attributes help to explain the abundance of F. prausnitzii in the colonic community but also suggest factors in the gut environment that may limit its distribution. PMID:22101049

  10. Molecular analysis of gut microbiota in obesity among Indian individuals

    Indian Academy of Sciences (India)

    Deepak P Patil; Dhiraj P Dhotre; Sachin G Chavan; Armiya Sultan; Dhawal S Jain; Vikram B Lanjekar; Jayshree Gangawani; Poonam S Shah; Jayshree S Todkar; Shashank Shah; Dilip R Ranade; Milind S Patole; Yogesh S Shouche

    2012-09-01

    Obesity is a consequence of a complex interplay between the host genome and the prevalent obesogenic factors among the modern communities. The role of gut microbiota in the pathogenesis of the disorder was recently discovered; however, 16S-rRNA-based surveys revealed compelling but community-specific data. Considering this, despite unique diets, dietary habits and an uprising trend in obesity, the Indian counterparts are poorly studied. Here, we report a comparative analysis and quantification of dominant gut microbiota of lean, normal, obese and surgically treated obese individuals of Indian origin. Representative gut microbial diversity was assessed by sequencing fecal 16S rRNA libraries for each group (n=5) with a total of over 3000 sequences. We detected no evident trend in the distribution of the predominant bacterial phyla, Bacteroidetes and Firmicutes. At the genus level, the bacteria of genus Bacteroides were prominent among the obese individuals, which was further confirmed by qPCR ( > 0.05). In addition, a remarkably high archaeal density with elevated fecal SCFA levels was also noted in the obese group. On the contrary, the treated-obese individuals exhibited comparatively reduced Bacteroides and archaeal counts along with reduced fecal SCFAs. In conclusion, the study successfully identified a representative microbial diversity in the Indian subjects and demonstrated the prominence of certain bacterial groups in obese individuals; nevertheless, further studies are essential to understand their role in obesity.

  11. Comparative cytotoxicity of periodontal bacteria

    International Nuclear Information System (INIS)

    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

  12. Real-time PCR detection of pathogenic microorganisms in roof-harvested rainwater in Southeast Queensland, Australia.

    Science.gov (United States)

    Ahmed, W; Huygens, F; Goonetilleke, A; Gardner, T

    2008-09-01

    In this study, the microbiological quality of roof-harvested rainwater was assessed by monitoring the concentrations of Escherichia coli, enterococci, Clostridium perfringens, and Bacteroides spp. in rainwater obtained from tanks in Southeast Queensland, Australia. Samples were also tested using real-time PCR (with SYBR Green I dye) for the presence of potential pathogenic microorganisms. Of the 27 rainwater samples tested, 17 (63%), 21 (78%), 13 (48%), and 24 (89%) were positive for E. coli, enterococci, C. perfringens, and Bacteroides spp., respectively. Of the 27 samples, 11 (41%), 7 (26%), 4 (15%), 3 (11%), and 1 (4%) were PCR positive for the Campylobacter coli ceuE gene, the Legionella pneumophila mip gene, the Aeromonas hydrophila lip gene, the Salmonella invA gene, and the Campylobacter jejuni mapA gene. Of the 21 samples tested, 4 (19%) were positive for the Giardia lamblia beta-giardin gene. The binary logistic regression model indicated a positive correlation (P < 0.02) between the presence/absence of enterococci and A. hydrophila. In contrast, the presence/absence of the remaining potential pathogens did not correlate with traditional fecal indicators. The poor correlation between fecal indicators and potential pathogens suggested that fecal indicators may not be adequate to assess the microbiological quality of rainwater and consequent health risk. PMID:18621865

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

    Science.gov (United States)

    Samanta, Ashis Kumar; Jayaram, C.; Jayapal, N.; Sondhi, N.; Kolte, A. P.; Senani, S.; Sridhar, M.; Dhali, A.

    2015-01-01

    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. PMID:26176779

  14. A rhizobium leguminosarum mutant defective in symbiotic iron acquisition

    International Nuclear Information System (INIS)

    Iron acquisition by symbiotic Rhizobium spp. is essential for nitrogen fixation in the legume root nodule symbiosis. Rhizobium leguminosarum 116, an ineffective mutant strain with a defect in iron acquisition, was isolated after nitrosoguanidine mutagenesis of the effective strain 1062. The pop-1 mutation in strain 116 imparted to it a complex phenotype, characteristic of iron deficiency. Several iron(III)-solubilizing agents, such as citrate, hydroxyquinoline, and dihydroxybenzoate, stimulated growth of 116 on low-iron solid medium; anthranilic acid, the R. leguminosarum siderophore, inhibited low-iron growth of 116. The initial rate of 55Fe uptake by suspensions of iron-starved 116 cells was 10-fold less than that of iron-starved wild-type cells. Electron microscopic observations revealed no morphological abnormalities in the small, white nodules induced by 116. Nodule cortical cells were filled with vesicles containing apparently normal bacteroids. No premature degeneration of bacteroids or of plant cell organelles was evident. The authors mapped pop-1 by R plasmid-mediated conjugation and recombination to the ade-27-rib-2 region of the R. leguminosarum chromosome. No segregation of pop-1 and the symbiotic defect was observed among the recombinants from these crosses. Cosmid pKN1, a pLAFR1 derivative containing a 24-kilobase-pair fragment of R. leguminosarum DNA, conferred on 116 the ability to grow on dipyridyl medium and to fix nitrogen symbiotically

  15. 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.

  16. Quantification of human-associated fecal indicators reveal sewage from urban watersheds as a source of pollution to Lake Michigan.

    Science.gov (United States)

    Templar, Hayley A; Dila, Deborah K; Bootsma, Melinda J; Corsi, Steven R; McLellan, Sandra L

    2016-09-01

    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 human Lachnospiraceae, 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 (land use, storm characteristics, and other factors that drive sewage contamination in urban waterways. PMID:27236594

  17. 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.

  18. AcEST: DK949283 [AcEST

    Lifescience Database Archive (English)

    Full Text Available 0.53 sp|A8EUE3|SECA_ARCB4 Protein translocase subunit secA OS=Arcobac... 34 0.53 sp|Q8CHG3|GCC2_MOUSE GRIP and coiled-coil...e OS=Metha... 32 2.0 sp|A6KYR3|SYM_BACV8 Methionyl-tRNA synthetase OS=Bacteroides vul... 32 2.6 sp|A2AQ25|SKT_MOUSE Sickle tail pro...sporter ATP-binding... 31 5.8 sp|Q8A3M1|SYM_BACTN Methionyl-tRNA synthetase OS=Bacteroides the... 31 5.8 sp|...merase OS=Tomato spotted wilt virus (strain Brazilian Br-01) GN=L PE=3 SV=1 Length = 2875 Score = 35.4 bits ...005_J06, 5' (618 letters) Database: uniprot_trembl.fasta 7,341,751 sequences; 2,3

  19. The Effects of Maturation on the Colonic Microflora in Infancy and Childhood

    Directory of Open Access Journals (Sweden)

    P. Enck

    2009-01-01

    Full Text Available The composition of colonic mircoflora and its changes with maturation have rarely been investigated in large samples. Methods. We used conventional microbiological testing to analyse the colonic flora (Kyberstatus, Institut forMicroecology, Herborn, Germany of stool samples from 12 484 children with different intestinal and nonintestinal diagnoses. Stool samples were analysed for total colony forming units (CFU (per g stool and the abundance of Bifidobacteria, Bacteroides sp., Escherichia coli, Enterococcus sp., and Lactobacillus sp. with respect to age, gender. A subset of 1089 infants was analysed for monthly changes within the first year of life. Results. Total CFU and individual microbial species were highest during the first year of life, decreased within the first 2 years, and then stabilized for the remaining childhood. In infants, the total CFU rose until month 5, declined with weaning, and peaked at 9–10 months. Significant effects of age, but not of gender, were found in Bacteroides sp. and Lactobacilli. However Bacterioids sp. and Lactobacilli increased with age, while Enterococci and E. coli decreased, and Bifidobacteria remained stable. Conclusion. Colonic microflora show both a bacteria-specific and general pattern of maturation which is most profound within the first year.

  20. Interferon Tau Affects Mouse Intestinal Microbiota and Expression of IL-17.

    Science.gov (United States)

    Ren, Wenkai; Chen, Shuai; Zhang, Liwen; Liu, Gang; Hussain, Tarique; Hao, Xiao; Yin, Jie; Duan, Jielin; Tan, Bie; Wu, Guoyao; Bazer, Fuller W; Yin, Yulong

    2016-01-01

    This study was conducted to explore the effects of interferon tau (IFNT) on the intestinal microbiota and expression of interleukin 17 (IL-17) in the intestine of mice. IFNT supplementation increased microbial diversity in the jejunum and ileum but decreased microbial diversity in the feces. IFNT supplementation influenced the composition of the intestinal microbiota as follows: (1) decreasing the percentage of Firmicutes and increasing Bacteroidetes in the jejunum and ileum; (2) enhancing the percentage of Firmicutes but decreasing Bacteroidetes in the colon and feces; (3) decreasing Lactobacillus in the jejunum and ileum; (4) increasing the percentage of Blautia, Bacteroides, Alloprevotella, and Lactobacillus in the colon; and (5) increasing the percentage of Lactobacillus, Bacteroides, and Allobaculum, while decreasing Blautia in the feces. Also, IFNT supplementation decreased the expression of IL-17 in the intestines of normal mice and of an intestinal pathogen infected mice. In conclusion, IFNT supplementation modulates the intestinal microbiota and intestinal IL-17 expression, indicating the applicability of IFNT to treat the intestinal diseases involving IL-17 expression and microbiota. PMID:27610003

  1. 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.

  2. Factors Influencing Fecal Contamination in Pond of Bangladesh

    Science.gov (United States)

    Knappett, P. S.; Escamilla, V.; Layton, A.; McKay, L. D.; Emch, M.; Mailloux, B. J.; Williams, D. E.; Huq, M. R.; Alam, M.; Farhana, L.; Ferguson, A. S.; Sayler, G. S.; Ahmed, K.; Serre, M. L.; Akita, Y.; Yunus, M.; van Geen, A.

    2010-12-01

    Occurrence of diarrheal disease in villages in rural Bangladesh remains relatively common, even though many households have switched to tubewell water for drinking and cooking. One factor contributing to this may be exposure to fecal contamination in ponds, which are often used for bathing and fishing. The objective of this study is to determine the dominant sources of fecal pollution in typical ponds and to explore the relationship between local population, latrine density, latrine quality and concentrations of fecal bacteria and pathogens in pond water. Forty-three ponds were sampled and analyzed for E. coli using culture-based methods and for E. coli, Bacteroides and adenovirus using quantitative PCR. Population and sanitation infrastructure were surveyed and compared to levels of pond fecal contamination. Molecular fecal source tracking using Bacteroides, determined that humans were the dominant source of fecal contamination in 79% of the ponds. Ponds directly receiving latrine effluent had the highest concentrations of fecal indicator bacteria. Concentrations of fecal indicator bacteria correlated with population surveyed within a distance of 30-70 m (pcattle. Since the majority of fecal pollution is from humans, use of pond water could help explain the persistence of diarrheal disease in rural Bangladesh.

  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. PMID:27306663

  4. Prebiotic stimulation of human colonic butyrate-producing bacteria and bifidobacteria, in vitro.

    Science.gov (United States)

    Scott, Karen P; Martin, Jennifer C; Duncan, Sylvia H; Flint, Harry J

    2014-01-01

    Dietary macronutrients affect the composition of the gut microbiota, and prebiotics are used to improve and maintain a healthy gut. The impact of prebiotics on dominant gut bacteria other than bifidobacteria, however, is under-researched. Here, we report carbohydrate utilisation patterns for representative butyrate-producing anaerobes, belonging to the Gram-positive Firmicutes families Lachnospiraceae and Ruminococcaceae, by comparison with selected Bacteroides and Bifidobacterium species. Growth assessments using anaerobic Hungate tubes and a new rapid microtitre plate assay were generally in good agreement. The Bacteroides strains tested showed some growth on basal medium with no added carbohydrates, utilising peptides in the growth medium. The butyrate-producing strains exhibited different growth profiles on the substrates, which included starch, inulin, fructooligosaccharides (FOS), galactooligosaccharides (GOS) and xylooligosaccharides (XOS). Eleven were able to grow on short-chain FOS, but this number decreased as the chain length of the fructan substrates increased. Long-chain inulin was utilised by Roseburia inulinivorans, but by none of the Bifidobacterium species examined here. XOS was a more selective growth substrate than FOS, with only six of the 11 Firmicutes strains able to use XOS for growth. These results illustrate the selectivity of different prebiotics and help to explain why some are butyrogenic. PMID:23909466

  5. Gut microbiome diversity in acute infective and chronic inflammatory gastrointestinal diseases in North India.

    Science.gov (United States)

    Kedia, Saurabh; Rampal, Ritika; Paul, Jaishree; Ahuja, Vineet

    2016-07-01

    The disease profile in the Indian population provides a unique opportunity for studying the host microbiome interaction in both infectious (amebiasis) and autoimmune diseases like inflammatory bowel disease (IBD) from a similar environment and genetic background. Analysis of fecal samples from untreated amebic liver abscess (ALA) patients, Entamoeba histolytica (Eh)-negative and -positive asymptomatic individuals, and pus samples from naive ALA patients revealed a significant reduction in Lactobacillus in asymptomatic individuals (Eh +ve) and ALA patients. Two anaerobic genera, namely Bacteroides and Peptostreptococcus, were detected in naive ALA pus samples. Analysis of fecal samples from amoebic colitis patients showed a significant decline in population of Bacteroides, Clostridium coccoides and leptum subgroup, Lactobacillus, Campylobacter, and Eubacterium, whereas a significant increase in Bifidobacterium was observed. Mucosa-associated bacterial flora analysis from IBD patients and healthy controls revealed a significant difference in concentration of bacteria among predominating and subdominating genera between ulcerative colitis (UC), Crohn's disease (CD) patients, and controls. In contrast to the mucosal studies, we found a significant increase in lactobacilli population in fecal samples of active UC patients. Another study revealed a significant decrease of Clostridium coccoides and leptum clusters in fecal samples of active UC patients along with decreased concentrations of fecal SCFAs, especially of n-butyrate, iso-butyrate, and acetate. We therefore found similar perturbations in gut microbiome in both infectious and autoimmune diseases, indicating inflammation to be the major driver for changes in gut microbiome. PMID:26994772

  6. 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

    2014-02-01

    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.

  7. 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.

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

    Science.gov (United States)

    Verstraelen, Hans; Vilchez-Vargas, Ramiro; Desimpel, Fabian; Jauregui, Ruy; Vankeirsbilck, Nele; Weyers, Steven; Verhelst, Rita; De Sutter, Petra; Pieper, Dietmar H; Van De Wiele, Tom

    2016-01-01

    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 Prevotella spp

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

    Directory of Open Access Journals (Sweden)

    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

  10. Antimicrobial activity of diterpenes from Viguiera arenaria against endodontic bacteria.

    Science.gov (United States)

    Carvalho, Tatiane C; Simão, Marília R; Ambrósio, Sérgio R; Furtado, Niege A J C; Veneziani, Rodrigo C S; Heleno, Vladimir C G; Da Costa, Fernando B; Gomes, Brenda P F A; Souza, Maria Gorete M; Borges dos Reis, Erika; Martins, Carlos H G

    2011-01-01

    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. PMID:21233793

  11. Microbial utilization and selectivity of pectin fractions with various structures.

    Science.gov (United States)

    Onumpai, Chatchaya; Kolida, Sofia; Bonnin, Estelle; Rastall, Robert A

    2011-08-15

    To evaluate the fermentation properties of oligosaccharides derived from pectins and their parent polysaccharides, a 5-ml-working-volume, pH- and temperature-controlled fermentor was tested. Six pectic oligosaccharides representing specific substructures found within pectins were prepared. These consisted of oligogalacturonides (average degrees of polymerization [DP] of 5 and 9), methylated oligogalacturonides (average DP of 5), oligorhamnogalacturonides (average DP of 10 as a disaccharide unit of galacturonic acid and rhamnose), oligogalactosides (average DP of 5), and oligoarabinosides (average DP of 6). The influence of these carbohydrates on the human fecal microbiota was evaluated. Use of neutral sugar fractions resulted in an increase in Bifidobacterium populations and gave higher organic acid yields. The Bacteroides-Prevotella group significantly increased on all oligosaccharides except oligogalacturonides with an average DP of 5. The most selective substrates for bifidobacteria were arabinan, galactan, oligoarabinosides, and oligogalactosides. PMID:21724897

  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. PMID:26572404

  13. Dicty_cDB: Contig-U16436-1 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available 5 e-114 CU633870_115( CU633870 |pid:none) Podospora anserina genomic DNA c... 344 e-114 AJ621287_1( AJ621287...015928 |pid:none) Bacteroides thetaiotaomicron VP... 39 0.90 CP000099_229( CP000099 |pid:none) Methanosarcina...nkkkkkkgrppp Translated Amino Acid sequence (All Frames) Frame A: LIFFFLININKFIIIEIKIFYFL...098096_5( EU098096 |pid:none) Blumeria graminis f. sp. hordei Av... 325 2e-99 A67854_1( A67854 |pid:none) Sequence 26 from Paten...0615_1648( CP000615 |pid:none) Burkholderia vietnamiensis G4 c... 271 8e-71 AM902716_277( AM902716 |pid:none) Bordetella petrii stra

  14. Dicty_cDB: Contig-U15026-1 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available bacteroides distasonis ATCC ... 89 6e-16 AP008209_848( AP008209 |pid:none) Oryza sativa (japonica cult...e-05 (Q080P6) RecName: Full=Cysteine desulfurase; EC=2.8.1.7... 52 9e-05 AE005672_828( AE005672 |pid:none) Streptococcus pneumoni...e) Homo sapiens cysteine desulfurase ... 64 2e-08 CP000107_402( CP000107 |pid:none) Ehrlichia canis str. J...l=Cysteine desulfurase; EC=2.8.1.7... 62 8e-08 AM920428_1570( AM920428 |pid:none) Penicillium chryso...e) Bifidobacterium longum DJO10A, c... 53 4e-05 (B4RMB8) RecName: Full=Cysteine desulfuras

  15. Dicty_cDB: Contig-U10444-1 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available e) Ralstonia solanacearum strain Mo... 236 8e-61 CP000103_850( CP000103 |pid:none) Nitrosospira mult...bacteroides distasonis ATCC ... 132 1e-29 AM412317_1614( AM412317 |pid:none) Clostridium botulinum A str...e S-acetyltransferase (EC 2.3.1.12)... 115 2e-24 AY596298_165( AY596298 |pid:none) Haloarcul...S-suc... 248 3e-64 A41015( A41015 ) dihydrolipoamide S-succinyltransferase (EC 2.3.1.... 247 3e-64 AB075013_1( AB075013 |pid:non...e S-succinyltransferase (EC 2.3.1.... 235 2e-60 CP000699_1289( CP000699 |pid:none) Sphingomonas

  16. Localization of acid phosphatase activity in the apoplast of root nodules of pea (Pisum sativum

    Directory of Open Access Journals (Sweden)

    Marzena Sujkowska

    2011-04-01

    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.

  17. Distribution of two triamines, spermidine and homospermidine, and an aromatic amine, 2-phenylethylamine, within the phylum Bacteroidetes.

    Science.gov (United States)

    Hosoya, Ryuichi; Hamana, Koei

    2004-10-01

    Cellular polyamines of the newly additional 19 species belonging to the class Bacteroides of the phylum Bacteroidetes were analyzed by HPLC to display polyamine distribution as a chemotaxonomic marker within the total 41 species. Three profiles, the presence of spermidine, the presence of homospermidine and the absence of both triamines, corresponded to their phylogenetical positions within the four families of the class. The occurrence of an aromatic amine, 2-phenylethylamine, extracted into cellular polyamine fraction, was also determined within the 121 species distributed within the phylum. This aromatic amine was found in Cellulophaga lytica, Cytophaga latercula, Tenacibaculum amylolyticum, Tenacibaculum martimum, Tenacibaculum mesophilum and Psychroflexus torquis belonging to the family Flavobacteriaceae of the class Flavobacteria, and Flexibacter flexilis and Microscilla marina belonging to the family Flexibacteraceae of the class Sphingobacteria. PMID:15747230

  18. Tenacibaculum skagerrakense sp. nov., a marine bacterium isolated from the pelagic zone in Skagerrak, Denmark.

    Science.gov (United States)

    Frette, Lone; Jørgensen, Niels O G; Irming, Heidi; Kroer, Niels

    2004-03-01

    A number of bacteria were isolated from sea water in Skagerrak, Denmark, at 30 m depth. Two of the isolates, strains D28 and D30(T), belonged to the Flavobacteriaceae within the Cytophaga-Flavobacterium-Bacteroides group. Sequencing of 16S rRNA genes of the two strains indicated strongly that they belonged to the genus Tenacibaculum and that they showed greatest similarity to the species Tenacibaculum amylolyticum and Tenacibaculum mesophilum. DNA-DNA hybridization values, DNA base composition and phenotypic characteristics separated the Skagerrak strains from the other species within TENACIBACULUM: Thus, it is concluded that the strains belong to a novel species within the genus Tenacibaculum, for which the name Tenacibaculum skagerrakense sp. nov. is proposed, with strain D30(T) (=ATCC BAA-458(T)=DSM 14836(T)) as the type strain. PMID:15023969

  19. Symbiotic leghemoglobins are crucial for nitrogen fixation in legume root nodules but not for general plant growth and development

    DEFF Research Database (Denmark)

    Ott, Thomas; van Dongen, Joost T; Günther, Catrin; Krusell, Lene; Desbrosses, Guilhem; Vigeolas, Helene; Bock, Vivien; Czechowski, Tomasz; Geigenberger, Peter; Udvardi, Michael K

    2005-01-01

    fixation (SNF). In legumes, SNF occurs in specialized organs, called nodules, which contain millions of nitrogen-fixing rhizobia, called bacteroids. The induction of nodule-specific plant genes, including those encoding symbiotic leghemoglobins (Lb), accompanies nodule development. Leghemoglobins...... accumulate to millimolar concentrations in the cytoplasm of infected plant cells prior to nitrogen fixation and are thought to buffer free oxygen in the nanomolar range, avoiding inactivation of oxygen-labile nitrogenase while maintaining high oxygen flux for respiration. Although widely accepted, this......RNAi plants grew normally when fertilized with mineral nitrogen. These data indicate roles for leghemoglobins in oxygen transport and buffering and prove for the first time that plant hemoglobins are crucial for symbiotic nitrogen fixation. Udgivelsesdato: 2005-Mar-29...

  20. Estimating Time Since Death from Postmortem Human Gut Microbial Communities.

    Science.gov (United States)

    Hauther, Kathleen A; Cobaugh, Kelly L; Jantz, Lee Meadows; Sparer, Tim E; DeBruyn, Jennifer M

    2015-09-01

    Postmortem succession of human-associated microbial communities ("human microbiome") has been suggested as a possible method for estimating postmortem interval (PMI) for forensic analyses. Here we evaluate human gut bacterial populations to determine quantifiable, time-dependent changes postmortem. Gut microflora were repeatedly sampled from the proximal large intestine of 12 deceased human individuals as they decayed under environmental conditions. Three intestinal bacterial genera were quantified by quantitative PCR (qPCR) using group-specific primers targeting 16S rRNA genes. Bacteroides and Lactobacillus relative abundances declined exponentially with increasing PMI at rates of Nt=0.977e(-0.0144t) (r2=0.537, pPMI. PMID:26096156

  1. 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...... using K+ concentration gradients and valinomycin, and the size of the imposed Delta psi was determined by measuring vesicle uptake of [C-14]tetraphenylphosphonium. Vesicle uptake of MA was driven by a negative Delta psi and was stimulated by a low extravesicular pH. Protonophore-induced collapse of the...... pH gradient indicated that uptake of MA was not related to the presence of a pH gradient. The MA-uptake mechanism appeared to have a large capacity for transport, and saturation was not observed at MA concentrations in the range of 25 mu M to 150 mM. MA uptake could be inhibited by NH4+, which...

  2. Dicty_cDB: Contig-U01814-1 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available a Primary Ear... 32 6.5 2 ( EH014515 ) USDA-FP_182321 Lysiphlebus testaceipes adult whol... 34 6.5 2 ( FD00...1 ) 285600 Tomato MboI BAC Library Solanum lycopersic... 34 6.4 2 ( CK402015 ) AUF_IfInt_205_d23 Ictalurus furcatus intest...s) Database: nrp_B 3,236,559 sequences; 1,051,180,864 total letters Searching..................72 |pid:none) Shewanella piezotolerans WP3, co... 103 7e-21 CP000139_1583( CP000139 |pid:none) Bacteroides v...00555_3148( CP000555 |pid:none) Methylibium petroleiphilum PM1,... 113 9e-24 ( Q0

  3. AcEST: DK962705 [AcEST

    Lifescience Database Archive (English)

    Full Text Available LSCPTCGKGGLTPEQRGER 127 >tr|A9PJC7|A9PJC7_POPJC Putative uncharacterized protein OS=Populus jackii PE=4 SV=1 Leng...-containing cysteine-ri... 36 0.13 sp|Q9Y2M2|CC032_HUMAN Uncharacterized protein C3orf3...p|Q64VI7|DNAJ_BACFR Chaperone protein dnaJ OS=Bacteroides fragi... 32 3.3 sp|Q5LED4|DNAJ_BACFN Chaperone protein dnaJ OS=Bac...teroides fragi... 32 3.3 sp|Q73T77|DNAJ2_MYCPA Chaperone protein dnaJ 2 OS=Mycobacterium ......ition tr|B6U3Z1|B6U3Z1_MAIZE Putative uncharacterized protein OS=Zea mays Align length 52

  4. Rhizobium Strain Effects on Yield and Bleeding Sap Amino Compounds in Pisum sativum

    DEFF Research Database (Denmark)

    Rosendahl, Lis

    1984-01-01

    for a higher percentage of the organic solutes transporting newly assimilated N from the root system than in the association with 1044. The Rhizobium strain effect on amino compound composition of the bleeding sap may indicate an influence of the bacteroids on either the N-assimilatory enzyme system......Bleeding sap composition, dry matter production and N distribution in pea (P. sativum L. cv. Bodil) grown with and without nitrate and nodulated with either R. leguminosarum strain 128c53 or strain 1044 were compared. Nitrate increased the total dry matter production of both symbioses, but...... relative to the total N-accumulation was greater with strain 128c53 due to a higher production of nodule tissue. The root bleeding sap of the symbiosis with the greater yield (strain 1044) contained high levels of asparagine and aspartic acid. In the 128c53 symbiosis, glutamine plus homoserine accounted...

  5. A novel bioinformatic strategy to characterise microbial communities in biogas reactors

    DEFF Research Database (Denmark)

    Treu, Laura; Campanaro, Stefano; De Francisci, Davide;

    2014-01-01

    16S hypervariable regions, especially when working with the not high quality very short reads characteristics of next generation sequencers (Mande S.S. et al., 2012). Previous works analysed the microbial community composition in biogas reactors via 16S rDNA sequencing (Luo, G. et al., 2013; Werner......, J.J. et al., 2011). For this reason we developed a bioinformatics strategy in order to create a tool to review the generated dataset and to obtain a more strict control on the bacterial composition at the species level, with estimation of its reliability. The program perform local similarity search......%). Bacteroides, Acetobacterium and Pseudomonas genera had difficulties in the assignment, gathering medium-low probability as well (1 to 50%). On the contrary several other genera were assigned with high probability and no multiple matches. Some of them including only one species uniquely identified, some other...

  6. AcEST: DK943515 [AcEST

    Lifescience Database Archive (English)

    Full Text Available L 730 >tr|Q8A4J5|Q8A4J5_BACTN Conserved protein found in conjugate transposon OS=Bacteroides...488 Definition Adiantum capillus-veneris mRNA. clone: YMU02A01NGRL0003_B07. 5' end sequence. Accession DK943...of protein database search programs, Nucleic Acids Res. 25:3389-3402. Query= DK943515|Adiantum capillus-veneris mRNA, clone...5 1.9 tr|Q8A4J5|Q8A4J5_BACTN Conserved protein found in conjugate tran... 35 2.4 tr|B0ULW0|B0ULW0_METS4 Phosphate butyryltransfer...YMU02A01NGRL0003_B07 488 Adiantum capillus-veneris mRNA. clone: YMU02A01NGRL0003_B0

  7. 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...

  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 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...

  9. AcEST: BP915528 [AcEST

    Lifescience Database Archive (English)

    Full Text Available GPSGEGYFRLTAFGSRENTLEAVERFK 406 >sp|Q64SY6|DAPAT_BACFR LL-diaminopimelate aminotransferase OS=Bacteroides fra...d_95, whole genome... 103 3e-21 tr|B6TIG6|B6TIG6_MAIZE Transaminase/ transferase, transferring n... 101 2e-2...opimelate aminotransferase OS=Geobacter sulfurreducens GN=dapL PE=3 SV=1 Length = 410 Scor...406 >sp|A5GD93|DAPAT_GEOUR LL-diaminopimelate aminotransferase OS=Geobacter uraniireducens (strain Rf4) GN=dapL PE=3 SV=1 Leng...6VMN8|Q6VMN8_ORYSJ Putative aminotransferase AGD2 OS=Oryza sativa subsp. japonica GN=AGD2 PE=2 SV=1 Length =

  10. Gene-microbiota interactions contribute to the pathogenesis of inflammatory bowel disease.

    Science.gov (United States)

    Chu, Hiutung; Khosravi, Arya; Kusumawardhani, Indah P; Kwon, Alice H K; Vasconcelos, Anilton C; Cunha, Larissa D; Mayer, Anne E; Shen, Yue; Wu, Wei-Li; Kambal, Amal; Targan, Stephan R; Xavier, Ramnik J; Ernst, Peter B; Green, Douglas R; McGovern, Dermot P B; Virgin, Herbert W; Mazmanian, Sarkis K

    2016-05-27

    Inflammatory bowel disease (IBD) is associated with risk variants in the human genome and dysbiosis of the gut microbiome, though unifying principles for these findings remain largely undescribed. The human commensal Bacteroides fragilis delivers immunomodulatory molecules to immune cells via secretion of outer membrane vesicles (OMVs). We reveal that OMVs require IBD-associated genes, ATG16L1 and NOD2, to activate a noncanonical autophagy pathway during protection from colitis. ATG16L1-deficient dendritic cells do not induce regulatory T cells (T(regs)) to suppress mucosal inflammation. Immune cells from human subjects with a major risk variant in ATG16L1 are defective in T(reg) responses to OMVs. We propose that polymorphisms in susceptibility genes promote disease through defects in "sensing" protective signals from the microbiome, defining a potentially critical gene-environment etiology for IBD. PMID:27230380

  11. Nosocomial diarrhea: evaluation and treatment of causes other than Clostridium difficile.

    Science.gov (United States)

    Polage, Christopher R; Solnick, Jay V; Cohen, Stuart H

    2012-10-01

    Diarrhea is common among hospitalized patients but the causes are distinct from those of diarrhea in the community. We review existing data about the epidemiology of nosocomial diarrhea and summarize recent progress in understanding the mechanisms of diarrhea. Clinicians should recognize that most cases of nosocomial diarrhea have a noninfectious etiology, including medications, underlying illness, and enteral feeding. Apart from Clostridium difficile, the frequency of infectious causes such as norovirus and toxigenic strains of Clostridium perfringens, Klebsiella oxytoca, Staphylococcus aureus, and Bacteroides fragilis remains largely undefined and test availability is limited. Here we provide a practical approach to the evaluation and management of nosocomial diarrhea when tests for C. difficile are negative. PMID:22700831

  12. AcEST: BP913416 [AcEST

    Lifescience Database Archive (English)

    Full Text Available GCATGTAGTTTGGA CAGAGATG ■■Homology search results ■■ - Swiss-Prot (release 56.9) Link to BlastX Result : Swi...AC_BACFN Uronate isomerase OS=Bacteroides fragilis (... 30 4.5 sp|Q3ITT7|SYA_NATPD Alanyl-tRNA synthetase OS=Natronomonas phar...C++ N IP+ M C Sbjct: 417 LSYPRHEYFRRTLCNLLGCDVENGEIPLSEMERVC 451 >sp|Q3ITT7|SYA_NATPD Alanyl-tRNA synthetase OS=Natronomonas phar...ng, Webb Miller, and David J. Lipman (1997), Gapped BLAST and PSI-BLAST: a new generation of protein database searc...148,809,765 total letters Searching..................................................done Score E Sequences

  13. Changes of Mouse Gut Microbiota Diversity and Composition by Modulating Dietary Protein and Carbohydrate Contents: A Pilot Study.

    Science.gov (United States)

    Kim, Eunjung; Kim, Dan-Bi; Park, Jae-Yong

    2016-03-01

    Dietary proteins influence colorectal cancer (CRC) risk, depending on their quantity and quality. Here, using pyrosequencing, we compared the fecal microbiota composition in Balb/c mice fed either a normal protein/carbohydrate diet (ND, 20% casein and 68% carbohydrate) or a high-protein/low-carbohydrate diet (HPLCD, 30% casein and 57% carbohydrate). The results showed that HPLCD feeding for 2 weeks reduced the diversity and altered the composition of the microbiota compared with the ND mice, which included a decrease in the proportion of the family Lachnospiraceae and Ruminococcaceae and increases in the proportions of the genus Bacteroides and Parabacteroides, especially the species EF09600_s and EF604598_s. Similar changes were reported in patients with inflammatory bowel disease, and in mouse models of CRC and colitis, respectively. This suggests that HPLCD may lead to a deleterious luminal environment and may have adverse effects on the intestinal health of individuals consuming such a diet. PMID:27069907

  14. Dicty_cDB: Contig-U08144-1 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available genome. 40 0.36 18 ( M34947 ) P.chabaudi major merozoite surface antigen mRNA, co... 42 0.38 3 ( AC215379 )...me... 89 2e-16 ( P29083 ) RecName: Full=General transcription factor IIE subunit ... 87 8e-16 AE014296_2125( AE014296 |pid:none) Dro..........................done Score E Sequences producing significant alignments: (bits) Value N ( BJ325481 ) Dictyostelium discoi...mosome 2 map 2234041... 34 2.3 14 ( DR146743 ) 49123921 Drosophila pseudoobscura embryonic...) RecName: Full=Trimethylamine methyltransferase mttB; ... 36 2.9 AE015928_4279( AE015928 |pid:none) Bacteroides thetaiotaomicro

  15. AcEST: DK954516 [AcEST

    Lifescience Database Archive (English)

    Full Text Available 17_GEOUR 50S ribosomal protein L17 OS=Geobacter uran... 31 6.3 sp|P23093|CSP_PLABA Circumsporozoite protein ...bable nucleoporin Nup58 OS=Drosophila melanogaster GN=Nup58 PE=1 SV=1 Length = 546 Score = 31.2 bit...tein 2 OS... 32 3.7 sp|Q9VDV3|NUPL1_DROME Probable nucleoporin Nup58 OS=Drosophila m... 31 4.8 sp|Q6W4X9|MUC...tein-L-isoaspartate O-methyltransferase ... 31 4.8 sp|Q64U07|SYI_BACFR Isoleucyl-tRNA synthetase OS=Bacteroi...des fra... 31 6.2 sp|Q5LCU8|SYI_BACFN Isoleucyl-tRNA synthetase OS=Bacteroides fra... 31 6.2 sp|P58415|COMD_

  16. AcEST: BP912108 [AcEST

    Lifescience Database Archive (English)

    Full Text Available Tektin-2 OS=Bos taurus GN=TEKT2 PE=2 SV=1 30 6.0 sp|P19260|MSA2_PLAFG Merozoite surface antigen 2, allelic f...QRVATEFAFRKRLREMEKLYSELKWQEKNTLE 288 Query: 182 EVA 174 E+A Sbjct: 289 EIA 291 >sp|P19260|MSA2_PLAFG Merozoit...CTN Galactose-binding-like protein OS=Bacteroides thetaiotaomicron GN=BT_1775 PE=4 SV=1 Length = 570 Score = 33.5 bit...is... 43 0.009 tr|B4PGP5|B4PGP5_DROYA GE21359 OS=Drosophila yakuba GN=GE21359 P... 35 ... SEDEAPRRSR+GEGKK+R Sbjct: 273 NSFRND--ESESEDEAPRRSRHGEGKKKR 299 >tr|B4PGP5|B4PGP5_DROYA GE21359 OS=Drosophi

  17. Characteristics of enriched cultures for bio-huff-`n`-puff tests at Jilin oil field

    Energy Technology Data Exchange (ETDEWEB)

    Xiu-Yuan Wang; Gang Dai; Yan-Fen Xue; Shu-Hua Xie [Institute of Microbiology, Beijing (China)] [and others

    1995-12-31

    Three enriched cultures (48, 15a, and 26a), selected from more than 80 soil and water samples, could grow anaerobically in the presence of crude oil at 30{degrees}C and could ferment molasses to gases and organic acids. Oil recovery by culture 48 in the laboratory model experiment was enhanced by 25.2% over the original reserves and by 53.7% over the residual reserves. Enriched culture 48 was composed of at least 4 species belonging to the genera Eubacterium, Fusobacterium, and Bacteroides. This enriched culture was used as inoculum for MEOR field trials at Jilin oil field with satisfactory results. The importance of the role of these isolates in EOR was confirmed by their presence and behavior in the fluids produced from the microbiologically treated reservoir.

  18. 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.

  19. Fluoroscence in situ hybridization of chicken intestinal samples with bacterial rRNA targeted oligonucleotide probes

    DEFF Research Database (Denmark)

    Olsen, Katja Nyholm; Francesch, M.; Christensen, Henrik

    2006-01-01

    338, Probe D and Non-EUB338 according to previous publications. Cultures of 38 bacterial strains representing type strains within the genera Bacillus, Listeria, Campylobacter, Bacteroides, Clostridium, Enterococcus, Streptococcus, Escherichia, Salmonella and Lactobacillus were used for optimization of......RNA of genera Lactobacillus, Bacillus, Enterococcus-Streptococcus, Enterobacteriaceae, Salmonella, Clostridium and Bacteriodes were around 1 ×108 bacterial cells per g of gut material. As for the EUB338 probe, huge variations were observed between the six different samples analysed even though each...... sample was obtained from a pool of six chickens allocated in the same cage. The technique will be used to investigate the effect of antimicrobials, feed additive, rearing conditions and Salmonella - and Campylobacter status on the bacterial composition of the chicken intestine....

  20. Human gut microbes impact host serum metabolome and insulin sensitivity

    DEFF Research Database (Denmark)

    Gudmundsdottir, Valborg; Hyotylainen, Tuulia; Nielsen, Trine;

    2016-01-01

    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 individ......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...

  1. Clindamycin and gentamicin for aerobic and anaerobic sepsis.

    Science.gov (United States)

    Fass, R J; Ruiz, D E; Gardner, W G; Rotilie, C A

    1977-01-01

    Thirty-eight adult patients with serious pleuropulmonary, soft-tissue, bone, and intra-abdominal infections caused by combinations of aerobic, facultative, and anaerobic bacteria were treated with parenterally given clindamycin phosphate and gentamicin sulfate and surgery when appropriate. Nine had associated bacteremia. In 29, infections failed to respond to other therapeutic regimens, which included penicillins, cephalosporins, aminoglycosides, and chloramphenicol. Results with clindamycin and gentamicin were excellent and were attributed primarily to the activity of clindamycin against anaerobes, particularly Bacteroides fragilis. Serum concentrations of clindamycin surpassed by manyfold the minimal inhibitory concentrations (MICs) for anaerobes. Serum concentrations of gentamicin did not consistently surpass the MICs for Enterobacteriaceae and Pseudomonas aeruginosa, although those organisms were consistently gentamicinsusceptible by disk diffusion susceptibility tests. Persistent colonization with Enterobacteriaceae, P aeruginosa, enterococci, or Candida were common, and occasionally they were significant in prolonging the clinical courses of patients with extensive infections. PMID:318824

  2. [Sensitivity of anaerobic bacteria to therapeutic agents (Zurich 1984)].

    Science.gov (United States)

    Wüst, J; Hardegger, U

    1985-12-28

    There are several reports in the literature on resistance of anaerobic bacteria against antimicrobial agents. Therefore, 231 anaerobic strains of various bacterial genera, isolated from clinical specimens during fall 1984, were tested for susceptibility to antimicrobial agents active against anaerobic bacteria. Whereas 23% of the Bacteroides species not belonging to the B. fragilis group were resistant to penicillin, the anaerobic bacteria were still susceptible to chloramphenicol, clindamycin and the nitroimidazoles. The resistance rate against the various new beta-lactam antibiotics was comparable to results of other studies. Due to the increasing resistance it is recommended that the susceptibility of clinically important anaerobes be tested by appropriate techniques. The agar diffusion test must not be used due to unreliable results. Instead, the minimal inhibitory concentration should be determined or the "broth-disk" test performed. PMID:4089587

  3. Anaerobic bacteria: evaluation of disc susceptibility to four cephalosporins.

    Science.gov (United States)

    Dubois, J; Pechère, J C

    1978-01-01

    The disc diffusion technique was evaluated with 178 strains of anaerobes and four cephalosporins (cephalothin, cefamandole, cefazolin and cefoxitin). Good correlation in results was found in comparison with the agar dilution technique (p less than 0.001) with the exception of cefamandole and cefazolin against anaerobic cocci (p greater than 0.05). Choosing a breakpoint of 8 microgram/ml for distinguishing susceptible and resistant strains, we determined corresponding incubation, the rate of error is less than 1% for false susceptible and less than 5% for false resistant. However, some strains of anaerobic cocci required a 48 hour incubation period for allowing visible growth. Moreover, a great deal (60.5%) of overlapping zone diameters made interpretation of disc diffusion test difficult among Bacteroides fragilis strains classed as susceptible, intermediate and resistant occuring with cefoxitin. The results have shown that the cephalothin disk will not accurately predict susceptibility of B. fragilis to cefoxitin. PMID:730395

  4. Infective endocarditis in bicuspid aortic valve: atrioventricular block as sign of perivalvular abscess.

    Science.gov (United States)

    Bacchion, Francesco; Cukon, Sonja; Rizzoli, Giulio; Gerosa, Gino; Daliento, Luciano; Thiene, Gaetano; Basso, Cristina

    2007-01-01

    A 46-year-old man presenting with fever, peripheral edema, and chest pain was admitted to the emergency department. Electrocardiogram showed sinus tachycardia and first-degree atrioventricular block. Transesophageal echocardiogram showed infective endocarditis in bicuspid aortic valve, complicated with severe aortic regurgitation, ring abscess, and sinus-of-Valsalva aneurysm extending to mitroaortic fibrous continuity. The patient, who was unaware of his bicuspid aortic valve condition, reported having undergone an orthodontic procedure complicated with dental abscess 1 month prior, which was treated with combined clavulanate-amoxicillin antibiotic therapy. Blood cultures were positive for Bacteroides fragilis resistant to metronidazole. Intravenous antibiotic therapy was undertaken, with rapid resolution of fever. He eventually underwent successful aortic homograft implantation and mitral valve repair with residual first-degree atrioventricular block. PMID:17637435

  5. 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.

  6. Dicty_cDB: Contig-U07978-1 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available ium discoideum chromoso... 699 0.0 CP000931_1519( CP000931 |pid:none) Shewanella halifa...us cereus subsp. cytotoxi... 442 e-122 CP000447_1317( CP000447 |pid:none) Shewanella frigidimarin...us cereus B4264, complete... 438 e-121 AE014299_1632( AE014299 |pid:none) Shewanella oneidens...:none) Bacteroides fragilis YCH46 DNA,... 342 3e-92 CP000697_24( CP000697 |pid:none) Acidip... 64 1e-06 3 ( AF513274 ) Francisella tularensis subsp. novicida isolate GA... 38 1e-06 5 ( FC815490 ) Sr_pAMT7_03e04_T7 S. ra

  7. Dicty_cDB: Contig-U10265-1 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available in6076, c... 33 8.5 CP000937_1480( CP000937 |pid:none) Francisella philomiragia subsp.... 33 8.5 C...P000478_144( CP000478 |pid:none) Syntrophobacter fumaroxidans MPO... 33 5.0 AP006841_3437( AP006841 |pid:none) Bacteroides fragi...cus asparagine-linke... 210 2e-53 BC044127_1( BC044127 |pid:none) Xenopus laevis asparagi...) Debaryomyces hansenii strain CBS... 179 6e-44 BC112581_1( BC112581 |pid:none) Bos taurus asparagine-linked...:none) Thermomicrobium roseum DSM 5159... 84 2e-15 BX842652_78( BX842652 |pid:none) Bdell

  8. Dicty_cDB: Contig-U15255-1 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available :none) Ralstonia eutropha JMP134 chrom... 97 5e-19 AP006841_3502( AP006841 |pid:none) Bacteroides fragi...om... 90 6e-17 CP000447_2048( CP000447 |pid:none) Shewanella frigidimarina NCIMB ... 90 6e-17 CS360325_1( CS360325 |pid... 7e-14 BX640416_135( BX640416 |pid:none) Bordetella pertussis strain Toha... 79 2e-13 CP001614_1734( CP001614 |pid...:none) Teredinibacter turnerae T7901, ... 78 3e-13 AM902716_379( AM902716 |pid:none) Bordetella petrii stra...in DSM 128... 77 4e-13 BX640429_59( BX640429 |pid:none) Bordetella parapertussis stra

  9. Dicty_cDB: Contig-U14933-1 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available :none) Saccharophagus degradans 2-40, ... 140 2e-55 CP000444_1874( CP000444 |pid:none) Shewanella...e-55 AP006841_4096( AP006841 |pid:none) Bacteroides fragilis YCH46 DNA,... 148 3e-55 AP008955_517( AP008955 |pid:none) Brevibacill...:none) Psychrobacter arcticus 273-4, com... 168 2e-72 CP000447_3258( CP000447 |pid:none) Shewanella frigid...:none) Acinetobacter baumannii ACICU, ... 169 2e-70 BX640429_39( BX640429 |pid:none) Bordetella parapertussis stra...tella pertussis strain Toha... 149 5e-70 AM902716_2813( AM902716 |pid:none) Bordetella petrii stra

  10. Dicty_cDB: Contig-U09878-1 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available 5 CP000447_3062( CP000447 |pid:none) Shewanella frigidimarina NCIMB ... 52 6e-05 CP001080_839( CP001080 |pid:none) Sulfurihydr... 82 1e-22 5 ( DY887765 ) CeleSEQ4425 Cunninghamella elegans pBluescript (E... 82 2e-22 5 ( C25696 ) Dictyostelium discoide...halogenans 2... 55 4e-06 AP006841_1122( AP006841 |pid:none) Bacteroides fragi...1e-05 BA000040_425( BA000040 |pid:none) Bradyrhizobium japonicum USDA 11... 54 1e-05 CP000302_2906( CP000302 |pid:none) Shewanella...mp... 52 3e-05 AE014299_3548( AE014299 |pid:none) Shewanella oneidensis MR-1, com... 52 3e-05 CP000685_416( CP000685 |pid:none) Fla

  11. Dicty_cDB: Contig-U04565-1 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available :none) Francisella philomiragia subsp.... 47 3e-04 AE017355_2939( AE017355 |pid:none) Bacillus thuringi...... 58 6e-13 4 ( ES566693 ) TPAF-aaa36g02.g1 T.spiralis_EST Trichinella spira... 58 1e-12 3 ( CV042354 ) tai55a05.y2 Hydra...i cDNA, mRNA sequence. 44 5.7 1 ( CR626927 ) Bacteroides fragilis NCTC 9343, comp...:none) Burkholderia glumae BGR1 plasmid ... 44 0.004 CP000608_600( CP000608 |pid:none) Francisella tula...itrophicus SB, c... 40 0.043 CP000447_2081( CP000447 |pid:none) Shewanella frigidimarina NCIMB ... 40 0

  12. Dicty_cDB: Contig-U12971-1 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available :none) Salinispora arenicola CNS-205, ... 46 5e-04 AE014299_1044( AE014299 |pid:none) Shewanella oneide...:none) Streptococcus mutans UA159, com... 50 2e-05 AP006841_673( AP006841 |pid:none) Bacteroides fragi...nsis MR-1, com... 46 5e-04 CP000447_3218( CP000447 |pid:none) Shewanella frigidimarina NCIMB ... 45 6e...:none) Helicoverpa armigera midgut aminop... 67 3e-10 AF020389_1( AF020389 |pid:none) Plutella xylostella...e-10 EU568874_1( EU568874 |pid:none) Helicoverpa armigera note Bt-Cry1A... 66 4e-10 AF109692_1( AF109692 |pid:none) Plutella

  13. 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. PMID:26574685

  14. Parotitis due to anaerobic bacteria.

    Science.gov (United States)

    Matlow, A; Korentager, R; Keystone, E; Bohnen, J

    1988-01-01

    Although Staphylococcus aureus remains the pathogen most commonly implicated in acute suppurative parotitis, the pathogenic role of gram-negative facultative anaerobic bacteria and strict anaerobic organisms in this disease is becoming increasingly recognized. This report describes a case of parotitis due to Bacteroides disiens in an elderly woman with Sjögren's syndrome. Literature reports on seven additional cases of suppurative parotitis due to anaerobic bacteria are reviewed. Initial therapy of acute suppurative parotitis should include coverage for S. aureus and, in a very ill patient, coverage of gram-negative facultative organisms with antibiotics such as cloxacillin and an aminoglycoside. A failure to respond clinically to such a regimen or isolation of anaerobic bacteria should lead to the consideration of the addition of clindamycin or penicillin. PMID:3287567

  15. AcEST: BP913800 [AcEST

    Lifescience Database Archive (English)

    Full Text Available |B4J5X5|B4J5X5_DROGR GH20808 OS=Drosophila grimshawi GN=GH2080... 37 0.67 tr|B2WFV8|B2WFV8_PYRTR Putative uncharacteri...m protein C OS=Bacteroides frag... 30 8.2 sp|Q9LUS3|PP237_ARATH Pentatricopeptide repeat...|Q5FG15|GPDA_EHRRG Glycerol-3-phosphate dehydrogenase [NAD(P)+] OS=Ehrlichia ruminantium (strain Gardel) GN=...|B4J5X5|B4J5X5_DROGR GH20808 OS=Drosophila grimshawi Align length 75 Score (bit) 36.6 E...zed protein OS=Pyren... 35 2.0 tr|Q8C5Y4|Q8C5Y4_MOUSE Putative uncharacteri

  16. Dicty_cDB: Contig-U10239-1 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available uctase subunit D; ... 130 4e-44 EU016667_23( EU016667 |pid:none) Uncultured marine microor...6 e-134 FJ859351_37( FJ859351 |pid:none) Micromonas sp. RCC299 mitochondri... 253 e-134 AY267353_16( AY26735...75_1724( CP001275 |pid:none) Thermomicrobium roseum DSM 5159... 135 2e-65 AP011115_5974( AP011115 |pid:none)...110 1e-50 AE015928_4063( AE015928 |pid:none) Bacteroides thetaiotaomicron VP... 116 1e-50 CP000932_1390( CP0...eductase subunit D 2; ... 160 1e-78 AY832208_1( AY832208 |pid:none) Eichhornia crassipes NADH dehydro

  17. Dicty_cDB: Contig-U16273-1 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available 3( EF106972 |pid:none) Uncultured marine Nitrospinaceae b... 107 4e-40 AE015928_1526( AE015928 |pid:none) Bacteroides thetaiotaomicro...r... 351 e-179 AY028259_1( AY028259 |pid:none) Avicennia marina myo-inositol 1-ph... 350 e-179 CP001574_495( CP001574 |pid:none) Micr...6 2 ( BF634972 ) NF077A08DT1F1056 Drought Medicago truncatula cDNA... 58 3e-06 2 ( CU701463 ) Phaeodactylum tricorn... partial ino... 38 1.1 CP001628_2218( CP001628 |pid:none) Micrococcus luteus NCTC 2665, c... 38 ...W477286 ) ga44e07.y1 Moss EST library PPU Physcomitrella pa... 36 2e-04 4 ( ES389624 ) MUS08-N15.x1d-t SHGC-MUS Mytilus californ

  18. Dicty_cDB: Contig-U16366-1 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available 274 2e-68 1 ( AF219101 ) Dictyostelium dimigraformum 18S ribosomal RNA gen... 272 6e-68 1 ( AF219107 ) Polysphondylium violac...98681_614( AM398681 |pid:none) Flavobacterium psychrophilum JIP... 42 0.15 (Q54G0...9 0.98 CP000102_217( CP000102 |pid:none) Methanosphaera stadtmanae DSM 30... 38 2.2 CP000771_697( CP000771 |pid:none) Fervidobacte...NARE domain... 37 2.8 BX571876_74( BX571876 |pid:none) Leptospira biflexa temperate bact... 37 2.8 AY372122_...RIKEN ... 36 6.3 CR626927_3516( CR626927 |pid:none) Bacteroides fragilis NCTC 9343,... 36 6.3 AJ318337_1( AJ318337 |pid:none) Pla

  19. Evaluation of antimicrobial efficacy of various root canal filling materials for primary teeth.

    Science.gov (United States)

    Pabla, T; Gulati, M S; Mohan, U

    1997-12-01

    Four materials viz. zinc oxide-eugenol, iodoform paste, Kri paste, Maisto's paste and Vitapex (Calcium hydroxide + iodoform) were tested for their antibacterial effect against the aerobic and anerobic bacteria, viz. Staphylococcus aureus, Streptococcus viridans, Streptococcus faecalis, Bacteroides melaninogenicus and mixed bacterial culture; obtained from infected non-vital deciduous anterior teeth. The antimicrobial sensitivity was checked on BHI-agar plates using well method. The results showed that all the 4 materials were distinctly different from each other in their antimicrobial activity. Maisto's paste was invariably the superior most in its antibacterial efficacy (in comparison to all the 5 micro-organism strains). Iodoformized zincoxide eugenol appeared to be the second best followed by Kri paste. Vitapex showed the least antibacterial activity. PMID:10635127

  20. Efficacy of a twelve-hourly ceftriaxone regimen in the treatment of serious bacterial infections.

    Science.gov (United States)

    Maslow, M J; Levine, J F; Pollock, A A; Simberkoff, M S; Rahal, J J

    1982-01-01

    Eighteen patients with 21 serious infections were treated with ceftriaxone, 1 g intravenously every 12 h, for a mean duration of 8 days. Eighteen gram-negative and two gram-positive organisms were isolated. Sites of infection included blood (three patients), urinary tract (six patients), respiratory tract (seven patients), biliary tract (three patients), ascitic fluid (one patient), and skin (one patient). Serum, bile, and ascitic fluid concentrations of ceftriaxone were in excess of the minimal bactericidal concentration required for the infecting organism in all cases. A bacteriological response was demonstrated in 94% of the infections. A clinical response occurred in four infections from which no pathogens were recovered. In one patient, ceftriaxone failed to eradicate a peritoneal infection due to Bacteroides fragilis. In two patients, superinfection with enterococci developed both during and after therapy. Systemic tolerance to ceftriaxone was excellent. PMID:6289735

  1. Gut Microbiota, Inflammation, and Colorectal Cancer.

    Science.gov (United States)

    Brennan, Caitlin A; Garrett, Wendy S

    2016-09-01

    Colorectal cancer is the second-leading cause of cancer-related deaths in the United States and fourth-leading cause of cancer-related deaths worldwide. While cancer is largely considered to be a disease of genetic and environmental factors, increasing evidence has demonstrated a role for the microbiota (the microorganisms associated with the human body) in shaping inflammatory environments and promoting tumor growth and spread. Herein, we discuss both human data from meta'omics analyses and data from mechanistic studies in cell culture and animal models that support specific bacterial agents as potentiators of tumorigenesis-including Fusobacterium nucleatum, enterotoxigenic Bacteroides fragilis, and colibactin-producing Escherichia coli. Further, we consider how microbes can be used in diagnosing colorectal cancer and manipulating the tumor environment to encourage better patient outcomes in response to immunotherapy treatments. PMID:27607555

  2. Detection and persistence of fecal Bacteroidales as water quality indicators in unchlorinated drinking water

    DEFF Research Database (Denmark)

    Saunders, Aaron Marc; Kristiansen, Anja; Lund, Marie Braad;

    2009-01-01

    doi:10.1016/j.syapm.2008.11.004 The results of this study support the use of fecal Bacteroidales qPCR as a rapid method to complement traditional, culture dependent, water quality indicators in systems where drinking water is supplied without chlorination or other forms of disinfection. A SYBR...... green based, quantitative PCR assay was developed to determine the concentration of fecal Bacteroidales 16S rRNA gene copies. The persistence of a Bacteroides vulgatus pure culture and fecal Bacteroidales from a wastewater inoculum was determined in unchlorinated drinking water at10°C. B. vulgatus 16S r......RNA gene copies persisted throughout the experimental period (200 days) in sterile drinking water but decayed faster in natural drinking water, indicating that the natural microbiota accelerated decay. In a simulated fecal contamination of unchlorinated drinking water, the decay of fecal Bacteroidales 16S...

  3. AcEST: BP918563 [AcEST

    Lifescience Database Archive (English)

    Full Text Available 88 >sp|B1H2Q2|ZRAN1_XENTR Ubiquitin thioesterase zranb1 OS=Xenopus tropicalis GN=...---CPNAVQQTKALPELA 348 >tr|B7AQJ2|B7AQJ2_9BACE Putative uncharacterized protein OS=Bacteroides pectinophilus... G... 30 9.1 sp|A1VT89|PURT_POLNA Phosphoribosylglycinamide formyltransferase... 30 9.2 sp|Q03495|POLN_HEVME Non-structural polypro...tein with coiled-coil OS=Mus musculus GN=Wac PE=1 SV=2 Length = 646 Score = 31.2 bits (69), Expect = 3.1 Identities...tein 38 OS=Xenopus tropicalis GN=rbm38 PE=2 SV=1 Length = 219 Score = 31.2 bits (69), Expect = 3.2 Identities

  4. Microbial source tracking(MST) and quantitative tracking of biological fecal contamination in water environment%MST与水环境生物源污染定量化溯源

    Institute of Scientific and Technical Information of China (English)

    郭萍; 李红娜; 李峰

    2016-01-01

    微生物溯源技术(Microbial source tracking,MST)通过靶标生物标记定位污染来源,为难以确定污染来源的非点源生物源污染监测提供了技术手段。基于微生物溯源技术从定性到定量化的发展历程,介绍了MST技术的产生、发展与特点以及MST在水环境污染监测与管理中的应用;重点论述了拟杆菌(Bacteroides spp.)基因标记水环境定量化溯源的研究进展,集中分析了温度、光照、盐度等环境因子对拟杆菌基因标记环境衰变的影响以及环境因子与定量化溯源结果准确性的相关关系,并据此判定环境生物因子可能对基因标记环境衰变结果存在一定的影响。依据目前定量溯源研究与应用现状,提出了提高拟杆菌定量溯源准确性和广泛性的研究重点和应用前景。%Microbial source tracking(MST)provides an accessible method for tracking the non-point contamination from biological sources, for it allows practitioners to discriminate among many possible sources of fecal contamination in the environmental waters by identifying the target biomarkers. In this paper, the origin, development process from qualitative to quantitative, characteristics and environmental applica-tions of MST technology were briefly reviewed. The screening criteria of microbes as indicators were developed. Bacteroides spp. as one of the accepted indicators showed some advantages in quantitative MST because this microbe couldn′t reproduce in vitro environment accord-ing to the criteria. The research on quantitative source tracking with Bacteroides spp. gene marker under different conditions has made a great progress. The research has been focused on the development of Bacteroides spp. gene-markers and their application to contamination source tracking at a quantitative level in water environment. The effects of environmental factors such as light, dark, temperature etc. on the decay of gene marks, and the

  5. [Effects of nifuroxazide on fecal flora in healthy subjects].

    Science.gov (United States)

    Buisson, Y; Larribaud, J

    1989-01-01

    Effect of nifuroxazide on fecal flora was studied in 12 healthy volunteers receiving, in hazardous order and double-blind procedure, three six-days courses of treatment separated by eight-days spaces of time: the conventional dosage of 400 mg twice a day, a dosage of 1200 mg once a day, and placebo. Among six settled bacteriological index (wealth of the fecal flora, percentage of gram-negative bacteria, numbers of E. coli, Enterococcus, Clostridium and Bacteroides), no significant variation was found by means of statistical study between D0, D2 and D7, nor between the three courses of treatment. Therefore nifuroxazide, even in high dosage, does not injure integrity of microbial intestinal ecosystem under so defined experimental conditions, similar with clinical conditions. PMID:2756516

  6. Engineering of Saccharomyces cerevisiae to utilize xylan as a sole carbohydrate source by co-expression of an endoxylanase, xylosidase and a bacterial xylose isomerase.

    Science.gov (United States)

    Mert, Marlin John; la Grange, Daniël Coenrad; Rose, Shaunita Hellouise; van Zyl, Willem Heber

    2016-04-01

    Xylan represents a major component of lignocellulosic biomass, and its utilization by Saccharomyces cerevisiae is crucial for the cost effective production of ethanol from plant biomass. A recombinant xylan-degrading and xylose-assimilating Saccharomyces cerevisiae strain was engineered by co-expression of the xylanase (xyn2) of Trichoderma reesei, the xylosidase (xlnD) of Aspergillus niger, the Scheffersomyces stipitis xylulose kinase (xyl3) together with the codon-optimized xylose isomerase (xylA) from Bacteroides thetaiotaomicron. Under aerobic conditions, the recombinant strain displayed a complete respiratory mode, resulting in higher yeast biomass production and consequently higher enzyme production during growth on xylose as carbohydrate source. Under oxygen limitation, the strain produced ethanol from xylose at a maximum theoretical yield of ~90 %. This study is one of only a few that demonstrates the construction of a S. cerevisiae strain capable of growth on xylan as sole carbohydrate source by means of recombinant enzymes. PMID:26749525

  7. Characteristics of extracellular polymeric substances and bacterial communities in an anaerobic membrane bioreactor coupled with online ultrasound equipment.

    Science.gov (United States)

    Yu, Zhiyong; Wen, Xianghua; Xu, Meilan; Huang, Xia

    2012-08-01

    Two parallel anaerobic membrane bioreactors (MBRs), integrated with or without ultrasound equipment for online membrane fouling control (US-AnMBR, or AnMBR) were established to digest waste activated sludge (WAS). The characteristics of bound extracellular polymeric substances (EPS) and bacterial communities in the systems were investigated for further understanding of the membrane fouling mechanisms. Ultrasound was an effective method for reducing cake layer resistance. A relatively high amount of bound EPS were found in the cake layer, especially for the US-AnMBR, by responding to the external forces (i.e. cross flow and ultrasound). High-throughput pyrosequencing and denaturing gradient gel electrophoresis (DGGE) were applied to analyze the bacterial diversity. Some bacterial populations contributing to membrane fouling were identified to accumulate in the cake layer, such as Peptococcaceae, Bacteroides and Syntrophobacterales. Since the ultrasounded retentate was recirculated back to the reactor, the bacterial community in the digested sludge was affected. PMID:22621809

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

    Directory of Open Access Journals (Sweden)

    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.

  9. Effect of chito-oligosaccharides over human faecal microbiota during fermentation in batch cultures.

    Science.gov (United States)

    Mateos-Aparicio, Inmaculada; Mengíbar, Marian; Heras, Angeles

    2016-02-10

    Chitosan with high number of deacetylated units, its reacetylated derivative and COS obtained through an enzymatic treatment with chitosanase were tested in pH controlled batch cultures to investigate the ability of the human faecal microbiota to utilise them. Chitosan derivatives with high number of deacetylated units decreased the bacterial populations: Bifidobacterium spp., Eubacterium rectale/Clostridium coccoides, C. Histolyticum and Bacteroides/Prevotella. On the other hand, chitosan derivatives with high content of acetylated residues maintained the tested bacterial groups and could increase Lactobacillus/Enterococcus. Regarding short chain fatty acids (SCFA), only low Mw COS increased the production in similar levels than fructo-oligossacharides (FOS). The acetylated chitosans and their COS do not appear as potential prebiotics but did not affect negatively the faecal microbiota, while derivatives with high number of deacetylated units could induce a colonic microbiota imbalance. PMID:26686171

  10. Synthesis of an Aminooxy Derivative of the Tetrasaccharide Repeating Unit of Streptococcus dysgalactiae 2023 Polysaccharide for a PS A1 Conjugate Vaccine.

    Science.gov (United States)

    Ghosh, Samir; Nishat, Sharmeen; Andreana, Peter R

    2016-06-01

    A highly efficient and stereocontrolled synthesis of an aminooxy derivative of the tetrasaccharide repeating unit of a rhamnose-rich polysaccharide isolated from the cell envelop of bovine mastitis Streptococcus dysgalactiae 2023 is reported for the first time. The synthesis was accomplished utilizing a stereoselective and convergent [2 + 2] glycosylation strategy inclusive of a disaccharide Schmidt donor and an inclusive rhamnose disaccharide acceptor. The synthetic aminooxy tetrasaccharide was conjugated to T-cell stimulating immunogen PS A1 from Bacteroides fragilis ATCC 25285/NCTC 9343 via a physiologically stable oxime linkage to furnish the first semisynthetic bacterial-based immunogen construct targeting S. dysgalactiae 2023. The synthetic tetrasaccharide was assembled in 19 steps with a ∼5.0% overall yield. PMID:27149417

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

    Science.gov (United States)

    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 agar medium, the isolate is inoculated on the surface, and the medium is incubated for 24 to 48 h. A 15-min test containing p-nitrophenyl polyglycosides as the substrate complex was developed to yield results comparable with the agar-based starch test. The reagent was made in liquid form, 0.20 ml per tube, and could be incubated either in ambient air or at 35 degrees C. When dried, the p-nitrophenyl polyglycoside reagent could be stored at 0 degrees C for 4 weeks. PMID:6418764

  12. AcEST: DK946160 [AcEST

    Lifescience Database Archive (English)

    Full Text Available 8. 5' end sequence. DK946160 CL242Contig1 Show DK946160 Clone id YMU02A01NGRL0011_K18 Library YMU02 Length 190 Definition Adiant...ein database search programs, Nucleic Acids Res. 25:3389-3402. Query= DK946160|Adiantum capillus-veneris mRN...core E Sequences producing significant alignments: (bits) Value sp|Q8A255|MRAY_BACTN Phospho-N-acetylmuramoyl-pentapeptide-tran...on of protein database search programs, Nucleic Acids Res. 25:3389-3402. Query= DK946160|Adiant...on sp|Q8A255|MRAY_BACTN Phospho-N-acetylmuramoyl-pentapeptide-transferase OS=Bacteroid

  13. Structure of BT-3984, a member of the SusD/RagB family of nutrient-binding molecules

    International Nuclear Information System (INIS)

    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

  14. [Epidemiology of the resistance to antibiotics at the Hospital Center of Aulnay-sous-Bois].

    Science.gov (United States)

    Le Pennec, M P; Caron, I; Chevallier, P; Giacomini, T

    1989-04-01

    Over the 14 month period (1/6/87-1/8/88) the majority of the bacteremia observed in the intensive unit (C.H. d'Aulnay) was due to Gram-positive bacteria (16/23 cases). The incidence of resistant to methicillin Staphylococcus aureus (SAMR) in blood culture was 10% in 1986 and 14% in 1987. Resistance of S. pneumoniae to penicillin was not detected; 30% of the 72 strains were resistant to erythromycin and 26% to tetracycline. Among Enterobacteriaceae, third generation cephalosporin is uncommon (2.8%) as gentamicin resistance (4.5%). Among the anaerobes, 57% of non Bacteroides fragilis group are resistant to penicillin. Nitroimidazole resistance was not detected. PMID:2789482

  15. 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

    The gut microbiota plays an important role in human health by interacting with host diet, but there is substantial inter-individual variation in the response to diet. Here we compared the gut microbiota composition of healthy subjects who exhibited improved glucose metabolism following 3-day...... 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...... increased potential to ferment complex polysaccharides after BKB. Finally, germ-free mice transplanted with microbiota from responder human donors exhibited improved glucose metabolism and increased abundance of Prevotella and liver glycogen content compared with germ-free mice that received non...

  16. AcEST: BP915499 [AcEST

    Lifescience Database Archive (English)

    Full Text Available |A6L2I2|A6L2I2_BACV8 Putative transmembrane transport protein ... 33 7.2 tr|A0QQ67|A0QQ67...|A6L2I2|A6L2I2_BACV8 Putative transmembrane transport protein OS=Bacteroides vulgatus (stra...ase OS=Mycobacterium smegmatis (strain ATCC 700084 / mc(2)155) GN=MSMEG_0645 PE=4 SV=1 Length = 280...15499 - Show BP915499 Clone id YMU001_000072_D03 Library YMU01 Length 486 Definition Adiantum capillus-vener...r G OS=Staphylococcus intermedius GN=fusA PE=3 SV=3 Length = 693 Score = 29.3 bit

  17. MgtE From Rhizobium leguminosarum Is a Mg²⁺ Channel Essential for Growth at Low pH and N2 Fixation on Specific Plants.

    Science.gov (United States)

    Hood, Graham; Karunakaran, Ramakrishnan; Downie, J Allan; Poole, Philip

    2015-12-01

    MgtE is predicted to be a Rhizobium leguminosarum channel and is essential for growth when both Mg²⁺ is limiting and the pH is low. N₂was only fixed at 8% of the rate of wild type when the crop legume Pisum sativum was inoculated with an mgtE mutant of R. leguminosarum and, although bacteroids were present, they were few in number and not fully developed. R. leguminosarum MgtE was also essential for N₂fixation on the native legume Vicia hirsuta but not when in symbiosis with Vicia faba. The importance of MgtE and the relevance of the contrasting phenotypes is discussed. PMID:26422403

  18. 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

    2015-01-01

    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. PMID:26040234

  19. 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.

  20. 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

  1. 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

  2. A novel sampling method for the investigation of gut microbiota

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    AIM: In order to characterize the qualitative and quantitative microorganisms in different sites of the lower digestive tract (LDT) in healthy volunteers, a specific technique was developed for collecting mucous of the distal ileum, colon and rectum.METHODS: A polyethylene tube was designed to go through the colonoscope channel with a No. 8 French tube. In order to avoid internal contamination, the distal extremity was protected with a membrane of microfilm after being sterilized in ethilene oxid. To facilitate the aspiration of a precise volume, its interior was coated with silicone. One hundred microlliter (0.1 mL) sample of mucous was collected and transferred into an Eppenddorff tube containing nine hundred microlliter (0.9 mL) of VMGA-3 (viable medium of Goteborg). This procedure was repeated at each site of the LDT with a new sterilized catheter.RESULTS: All sites revealed the "non pathogenic"anaerobic bacteria Veillonella sp (average 105 colony forming units/mL-CFU/mL), allowing to conclude an environment of low oxidation-reduction potential (redox)in the LDT. It was also characterized the presence of Klebisiella sp with significant statistical predominance (SSP) in the ileum. Enterobacter sp was found with SSP in the sigmoid colon, BacteroideS sp non-pigmented (npg)and E. coli with SSP in the sigmoid colon and rectum,Enterococcus sp and Lactobacillus sp with SSP in the rectum, all in a mean concentration of 105 CFU/mL.CONCLUSION: This procedure is feasible and efficient and can point out a similar distribution of the aerobic and anaerobic bacteria with the presence of biological markers of normal microbiota in the LDT.

  3. 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.

  4. Monitoring of microbial community structure and succession in the biohydrogen production reactor by denaturing gradient gel electrophoresis (DGGE)

    Institute of Scientific and Technical Information of China (English)

    XING; Defeng; REN; Nanqi; GONG; Manli; LI; Jianzheng; LI; Q

    2005-01-01

    To study the structure of microbial communities in the biological hydrogen production reactor and determine the ecological function of hydrogen producing bacteria, anaerobic sludge was obtained from the continuous stirred tank reactor (CSTR) in different periods of time, and the diversity and dynamics of microbial communities were investigated by denaturing gradient gel electrophoresis (DGGE). The results of DGGE demonstrated that an obvious shift of microbial population happened from the beginning of star-up to the 28th day, and the ethanol type fermentation was established. After 28 days the structure of microbial community became stable, and the climax community was formed. Comparative analysis of 16S rDNA sequences from reamplifying and sequencing the prominent bands indicated that the dominant population belonged to low G+C Gram-positive bacteria (Clostridium sp. And Ethanologenbacterium sp.), β- proteobacteria (Acidovorax sp.), γ-proteobacteria (Kluyvera sp.), Bacteroides (uncultured bacterium SJA-168), and Spirochaetes (uncultured eubacterium E1-K13), respectively. The hydrogen production rate increased obviously with the increase of Ethanologenbacterium sp., Clostridium sp. And uncultured Spirochaetes after 21 days, meanwhile the succession of ethanol type fermentation was formed. Throughout the succession the microbial diversity increased however it decreased after 21 days. Some types of Clostridium sp. Acidovorax sp., Kluyvera sp., and Bacteroides were dominant populations during all periods of time. These special populations were essential for the construction of climax community. Hydrogen production efficiency was dependent on both hydrogen producing bacteria and other populations. It implied that the co-metabolism of microbial community played a great role of biohydrogen production in the reactors.

  5. Correlation between body mass index and faecal microbiota from children.

    Science.gov (United States)

    Ignacio, A; Fernandes, M R; Rodrigues, V A A; Groppo, F C; Cardoso, A L; Avila-Campos, M J; Nakano, V

    2016-03-01

    Childhood obesity is an increasing problem at the global level and considered as a risk factor for obesity development and the associated co-morbidities in adult life. In this study, the occurrence of Bacteroides fragilis group, Clostridium spp., Bifidobacterium spp. and Escherichia coli in 84 faecal samples from 30 obese, 24 overweight and 30 lean children was verified by culture technique and quantitative determination by quantitative PCR. In addition, Lactobacillus spp. and Methanobrevibacter smithii were also analysed. A correlation between the body mass index (BMI) and these bacteria was sought. Bacteroides vulgatus, Clostridium perfringens and Bifidobacterium adolescentis were most prevalent in all samples evaluated by culture-method. The B. fragilis group were found at high concentrations in obese and overweight children when compared with the lean ones (p 0.015). The obese and overweight children harboured higher numbers of Lactobacillus spp. than lean children (p 0.022). The faecal concentrations of the B. fragilis group (r = 0.24; p 0.026) and Lactobacillus spp. (r = 0.44; p 0.002) were positively correlated with BMI. Bifidobacterium spp. were found in higher numbers in the lean group than the overweight and obese ones (p 0.042). Furthermore, a negative correlation between BMI and Bifidobacterium spp. copy number (r = -0.22; p 0.039) was observed. Our findings show some difference in the intestinal microbial ecosystem of obese children compared with the lean ones and a significant association between number of Lactobacillus spp. and B. fragilis group and BMI. PMID:26551842

  6. Fish Oil Enhances Recovery of Intestinal Microbiota and Epithelial Integrity in Chronic Rejection of Intestinal Transplant

    Science.gov (United States)

    Li, Qiurong; Zhang, Qiang; Wang, Chenyang; Tang, Chun; Zhang, Yanmei; Li, Ning; Li, Jieshou

    2011-01-01

    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. PMID:21698145

  7. Comparative in vitro activity of ceftaroline, ceftaroline-avibactam, and other antimicrobial agents against aerobic and anaerobic bacteria cultured from infected diabetic foot wounds.

    Science.gov (United States)

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

    2013-07-01

    Foot infections are the most common infectious complication of diabetes. Moderate to severe diabetic foot infections (DFI) are typically polymicrobial with both aerobic and anaerobic organisms. The role of MRSA in these wounds has become an increasing concern. To determine if the addition of avibactam, a novel non-beta-lactam beta-lactamase inhibitor, to ceftaroline would be more active than ceftaroline alone, we tested 316 aerobic pathogens and 154 anaerobic recovered from patients with moderate to severe DFI, and compared ceftaroline with and without avibactam to other agents. Testing on aerobes was done by broth microdilution and by agar dilution for anaerobes, according to CLSI M11-A8, and M7-A8 standards. Ceftaroline-avibactam MIC90 for all Staphylococcus spp. including MRSA was 0.5 μg/mL, and for enterococci was 1 μg/mL. The MIC90s for enteric Gram-negative rods was 0.125 μg/mL. The addition of avibactam to ceftaroline reduced the ceftaroline MICs for 2 strains of resistant Enterobacter spp. and for 1 strain of Morganella. Against anaerobic Gram-positive cocci ceftaroline-avibactam had an MIC90 0.125 μg/mL and for clostridia 1 μg/mL. Avibactam improved ceftaroline's MIC90s for Bacteroides fragilis from >32 to 2 μg/mL and for Prevotella spp. from >32 to 1 μg/mL. Ceftaroline alone demonstrates excellent in vitro activity against most of the aerobes found in moderate to severe DFI. The addition of avibactam provides an increased spectrum of activity including the beta-lactamase producing Prevotella, Bacteroides fragilis and ceftaroline resistant gram-negative enteric organisms. PMID:23623385

  8. 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 BACKGROUND & AIMS: 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. METHODS: 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. RESULTS: 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. CONCLUSIONS: CF causes qualitative and quantitative changes in intestinal microbiota, which may represent a novel therapeutic target in the treatment of CF

  9. Bases farmacomicrobiológicas del tratamiento antibiótico de las enfermedades periodontales y periimplatarias Farmacobiological concepts in the antibiotic treatment of the periodontal diseases

    Directory of Open Access Journals (Sweden)

    J. Liñares

    2003-12-01

    Full Text Available La enfermedad periodontal debe considerarse un proceso infeccioso bacteriano crónico. En su etiología, no hay una única especie bacteriana implicada, sino que podríamos considerarla como una infección polimicrobiana en la que estarían implicados diversos microorganismos. Las bacterias que se han asociado más directamente con la enfermedad periodontal son Actinobacillus actinomycetemcomitans, Porphyromonas gingivalis, Prevotella intermedia, Bacteroides forsythus y Treponema denticola. Los parámetros farmacodinámicos de los antibióticos son muy útiles a la hora de seleccionar pautas posológicas. El aumento de resistencias producido en muchos periodontopatógenos en los últimos años ha relegado a algunos antibióticos a un segundo plano. Entre la gran variedad de antibióticos utilizados, se han obtenido buenas respuestas terapéuticas con amoxicilina/ácido clavulánico, metronidazol, clindamicina, doxiciclina y las combinaciones de metronidazol más amoxicilina y metronidazol más amoxicili-na/ácido clavulánico.Periodontal disease must be considered a chronic bacterial infection. It does not appear to one single bacterial species that is uniquely involved. Rather, periodontal disease seems to be a polymicrobial infection involving several organisms. The bacteria most often associated with periodontal disease are Actinobacillus actinomycetemcomitans, Porphyromonas gingivalis, Prevotella intermedia, Bacteroides forsythus y Treponema denticola. Pharmacodynamics parameters are very useful to select dosing regimens. The increase in prevalence of resistance occurred in some periodontopathogens in the last years has pushed some antibiotics into the background. Positive responses have been reported with amoxicillin/clavulanate, metronidazole, clindamycin, doxycycline and the combination therapy metronidazole plus amoxicillin and metronidazole plus amoxicillin/clavulanate.

  10. Mortality in necrotizing fasciitis

    International Nuclear Information System (INIS)

    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)

  11. A comparative cytological and morphometric analysis of vacuolation in central tissue of the effective and ineffective pea (Pisum sativum L. root nodules

    Directory of Open Access Journals (Sweden)

    Wojciech Borucki

    2011-04-01

    Full Text Available Vacuoles play very important physiological roles in plant cells. Pea root nodules, which exhibit distinct zonation (meristematic zone and central tissue zones, may serve as a good experimental model for the investigations of vacuole development and its importance to cell and tissue functioning. Moreover, the nodule central tissue is composed of both infected and uninfected cells which play different physiological roles and differ in the level of vacuolation. Cytological observations revealed that central vacuoles of the infected cells of the effective nodules expand toward cell walls. Thus only thin layers of the cytoplasm separate each central vacuole from plasma membrane and cell wall. This finding is discussed from the viewpoint of improved exchange of solutes and water between the central vacuole and apoplast of the infected cell. Three-dimensional reconstruction of the vacuoles of infected cells within a fragment of effective nodule central tissue, showed their spatial arrangement. Possible advantages coming from the spatial arrangement of vacuoles within the central tissue are discussed. A comparative study of the central tissue (bacteroidal tissue and meristem vacuolation of the effective and ineffective pea root nodules is also presented. Morphometric measurements revealed that the effective nodule central tissue was more vacuolated than the ineffective one. It was proved that maturation of the infected cells involves dynamic changes in their vacuolation. Having numerous fixing nitrogen bacteroids, the infected cells of effective central tissue were less vacuolated than uninfected cells. On the other hand, both infected and uninfected cells of the effective central tissue showed a much higher level of vacuolation in nitrogen-fixing zone than cells of the same type in ineffective tissue. These results indicate that vacuolation is an important factor in development and functioning of pea root nodule central tissue.

  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. [Antimicrobial susceptibility of clinical isolates of aerobic Gram-positive cocci and anaerobic bacteria in 2006].

    Science.gov (United States)

    Yamaguchi, Takahiro; Yoshida, Isamu; Itoh, Yoshihisa; Tachibana, Mineji; Takahashi, Choichiro; Kaku, Mitsuo; Kanemitsu, Keiji; Okada, Masahiko; Horikawa, Yoshinori; Shiotani, Joji; Kino, Hiroyoshi; Ono, Yuka; Baba, Hisashi; Matsuo, Shuji; Asari, Seishi; Toyokawa, Masahiro; Matsuoka, Kimiko; Kusano, Nobuchika; Nose, Motoko; Murase, Mitsuharu; Miyamoto, Hitoshi; Saikawa, Tetsunori; Hiramatsu, Kazufumi; Kohno, Shigeru; Yanagihara, Katsunori; Yamane, Nobuhisa; Nakasone, Isamu; Maki, Hideki; Yamano, Yoshinori

    2010-12-01

    The activity of antibacterial agents against aerobic Gram-positive cocci (26 species, 1022 strains) and anaerobic bacteria (23 species, 184 strains) isolated from clinical specimens in 2006 at 16 clinical facilities in Japan were studied using either broth microdilution or agar dilution method. The ratio of methicillin-resistant strains among Staphylococcus aureus and Staphylococcus epidermidis was 53.0% and 65.8%, suggesting that resistant strains were isolated at high frequency. Vancomycin (VCM) and quinupristin/dalfopristin (QPR/DPR) had good antibacterial activity against methicillin-resistant S. aureus and methicillin-resistant S. epidermidis, with MIC90s of < or = 2 micrcog/mL. The ratio of penicillin (PC) intermediate and resistant strains classified by mutations of PC-binding proteins among Streptococcus pneumoniae was 87.6%. Ceftriaxone, cefpirome, cefepime, carbapenem antibiotics, VCM, teicoplanin, linezolid(LZD) and QPR/DPR had MIC90s of < or = 1 microg/mL against PC-intermediate and resistant S. pneumoniae strains. Against all strains of Enterococcus faecalis and Enterococcus faecium, the MICs of VCM and TEIC were under 2 microg/mL, and no resistant strain was detected, suggesting that these agents had excellent activities against these species. 10.9% of E. faecalis strains or 3.5% of E. faecium strains showed intermediate or resistant to LZD. 24.4% of E. faecium strains showed intermediate or resistant to QPR/DPR. Against all strains of Clostridium difficile, the MIC of VCM were under 1 microg/mL, suggesting that VCM had excellent activity against C. difficile. Carbapenems showed good activity against Peptococcaceae, Bacteroides spp., and Prevotella spp. However since several strains of Bacteroides fragilis showed resistant to carbapenems and the susceptibility of this species should be well-focused in the future. PMID:21425596

  14. [Antimicrobial susceptibility of clinical isolates of aerobic gram-positive cocci and anaerobic bacteria in 2008].

    Science.gov (United States)

    Yoshida, Isamu; Yamaguchi, Takahiro; Kudo, Reiko; Fuji, Rieko; Takahashi, Choichiro; Oota, Reiko; Kaku, Mitsuo; Kunishima, Hiroyuki; Okada, Masahiko; Horikawa, Yoshinori; Shiotani, Joji; Kino, Hiroyoshi; Ono, Yuka; Fujita, Shinichi; Matsuo, Shuji; Kono, Hisashi; Asari, Seishi; Toyokawa, Masahiro; Kusano, Nobuchika; Nose, Motoko; Horii, Toshinobu; Tanimoto, Ayako; Miyamoto, Hitoshi; Saikawa, Tetsunori; Hiramatsu, Kazufumi; Kohno, Shigeru; Yanagihara, Katsunori; Yamane, Nobuhisa; Nakasone, Isamu; Maki, Hideki; Yamano, Yoshinori

    2012-02-01

    The activity of antibacterial agents against aerobic Gram-positive cocci (25 genus or species, 1029 strains) and anaerobic bacteria (21 genus or species, 187 strains) isolated from clinical specimens in 2008 at 16 clinical facilities in Japan were studied using either broth microdilution or agar dilution method. The ratio of methicillin-resistant strains among Staphylococcus aureus and Staphylococcus epidermidis was 59.6% and 81.2%, suggesting that resistant strains were isolated at high frequency. Vancomycin (VCM), linezolid (LZD) and quinupristin/dalfopristin (QPR/DPR) had good antibacterial activity against methicillin-resistant S. aureus and methicillin-resistant S. epidermidis, with MIC90s of < or = 2 microg/mL. The ratio of penicillin (PC) intermediate and resistant strains classified by mutations of PC-binding proteins among Streptococcus pneumoniae was 92.0% that was highest among our previous reports. Cefpirome, carbapenems, VCM, teicoplanin (TEIC), LZD and QPR/DPR had MIC90s of < or = 1 microg/mL against PC-intermediate and resistant S. pneumoniae strains. Against all strains of Enterococcus faecalis and Enterococcus faecium, the MICs of VCM and TEIC were under 2 microg/mL, and no resistant strain was detected, suggesting that these agents had excellent activities against these species. 15.9% of E. faecalis strains and 1.2% of E. faecium strains showed intermediate to LZD. 17.1% of E. faecium strains showed intermediate or resistant to QPR/DPR. Against all strains of Clostridium difficile, the MIC of VCM was under 1 microg/mL, suggesting that VCM had excellent activity. Carbapenems showed good activity against Clostridiales, Bacteroides spp., and Prevotella spp., but one strain of Bacteroides fragilis showed resistant to carbapenems. And so, the susceptibility of this species should be well-focused in the future at detecting continuously. PMID:22808693

  15. Helicobacter species ribosomal DNA in the pancreas, stomach and duodenum of pancreatic cancer patients

    Institute of Scientific and Technical Information of China (English)

    Hans-Olof Nilsson; Unne Stenram; Ingemar Ihse; Torkel Wadstr(o)m

    2006-01-01

    AIM: To determine whether gastric and enteric Helico-bacter species are associated with pancreatic cancer.METHODS: Patients with exocrine pancreatic cancer(n = 40), neuroendocrine cancer (n = 14), multipleendocrine neoplasia type 1 (n = 8), and chronic pan-creatitis (n = 5) were studied. Other benign pancreat-ic diseases (n = 10) and specimens of normal pancre-as (n = 7) were included as controls. Pancreatic tissuespecimens were analyzed by Helicobacter-specificPCR-assay and products were characterized by dena-turing gradient electrophoresis and DNA-sequencing.From a subset of the pancreatic cancer patients, gas-tric and/or duodenal tissue as well as gallbladder andductus choledochus tissue were analyzed. Gallbladderand choledochus samples were included as controls.Stomach and duodenum samples were investigated toanalyze whether a gastric helicobacter might dissemi-nate to the pancreas in pancreatic cancer patients.Pancreatic specimens were analyzed by Bacteroides-specific PCR for detecting the translocation of indig-enous gut microbes to the diseased pancreas.RESULTS: Helicobacter DNA was detected in pancreas(tumor and/or surrounding tissue) of 75% of patientswith exocrine cancer, 57% of patients with neuro-endocrine cancer, 38% of patients with multiple eh-docrine neoplasia, and 60% of patients with chronicpancreatitis. All samples from other benign pancreaticdiseases and normal pancreas were negative. Thirty-three percent of the patients were helicobacter-positive in gastroduodenal specimens. Surprisingly,H. bilis was identified in 60% of the positive gastro-duodenal samples. All gallbladder and ductus cho-ledochus specimens were negative for helicobacter.Bacteroides PCR-assay was negative for all pancreaticsamples.CONCLUSION: Helicobacter DNA commonly detectedin pancreatic cancer suggests a possible role of theemerging pathogens in the development of chronicpancreatitis and pancreatic cancer.

  16. 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

  17. 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

  18. Progreso en el conocimiento de la microbiota intestinal humana

    Directory of Open Access Journals (Sweden)

    Virginia Robles-Alonso

    2013-06-01

    Full Text Available La aparición de nuevas técnicas de secuenciación así como el desarrollo de herramientas bioinformáticas han permitido no sólo describir la composición de la comunidad bacteriana que habita el tracto gastrointestinal, sino también las funciones metabólicas de las que proveen al huésped. La mayoría de los miembros de esta amplia comunidad bacteriana pertenecen a Dominio Bacteria, aunque encontramos también Archaea y formas eucariotas y virus. Únicamente entre 7 y 9 de las 55 Phyla del Dominio Bacteria conocidos están presentes en flora fecal humana. Su mayoría pertenecen además a las Divisiones Bacteroidetes and Firmicutes, encontrando también Proteobacteria, Actinobacteria, Fusobacteria y Verrucomicrobia. Bacteroides, Faecalibacterium y Bifidobacterium son los Géneros más abundantes aunque su abundancia relativa es muy variable entre individuos. El análisis metagenómico de la flora intestinal ha permitido describir una colección de 5 millones de genes microbianos que codifican para aproximadamente 20.000 funciones biológicas relacionadas con la vida de las bacterias. El ecosistema intestinal humano puede clasificarse en torno a tres grupos de acuerdo a la abundancia relativa de tres Géneros: Bacteroides (enterotipo 1, Prevotella (enterotipo 2 y Ruminococcus (enterotype 3. Estos grupos han sido denominados "enterotipos" y su descripción sugiere que las variaciones entre individuos están estratificadas. Una vez descrita la composición bacteriana sería interesante establecer la relación entre la alteración de equilibrios ecológicos con estados de enfermedad que puedan desembocar en una novedosa vía terapéutica.

  19. Throwing the dice for the diagnosis of vaginal complaints?

    Directory of Open Access Journals (Sweden)

    Taras David

    2006-02-01

    Full Text Available Abstract Backround Vaginitis is among the most common conditions women are seeking medical care for. Although these infections can easily be treated, the relapse rate is high. This may be due to inadequate use of the diagnostic potential. Methods We evaluated the misjudgement rate of the aetiology of vaginal complaints. A total of 220 vaginal samples from women with a vaginal complaint were obtained and analysed for numbers of total lactobacilli, H2O2-producing lactobacilli, total aerobic cell counts and total anaerobic cell counts including bifidobacteria, Bacteroides spp., Prevotella spp. Additionally, the presence of Atopobium vaginae, Gardnerella vaginalis, Candida spp. and Trichomonas vaginalis was evaluated by DNA-hybridisation using the PCR and Affirm VPIII Microbial Identification Test, respectively. Results The participating physicians diagnosed Bacterial vaginosis (BV as origin of discomfort in 80 cases, candidiasis in 109 cases and mixed infections in 8 cases. However, a present BV, defined as lack of H2O2-lactobacilli, presence of marker organisms, such as G. vaginalis, Bacteroides spp. or Atopobium vaginae, and an elevated pH were identified in only 45 cases of the women examined. Candida spp. were detected in 46 cases. Interestingly, an elevated pH corresponded solely to the presence of Atopobium vaginae, which was detected in 11 cases. Conclusion Errors in the diagnosis of BV and candida vulvovaginitis (CV were high. Interestingly, the cases of misjudgement of CV (77% were more numerous than that of BV (61%. The use of Amsel criteria or microscopy did not reduce the number of misinterpretations. The study reveals that the misdiagnosis of vaginal complaints is rather high.

  20. Multicentre survey of the comparative in-vitro activity of piperacillin/tazobactam against bacteria from hospitalized patients in the British Isles.

    Science.gov (United States)

    Chen, H Y; Bonfiglio, G; Allen, M; Piper, D; Edwardson, T; McVey, D; Livermore, D M

    1993-08-01

    Twenty-nine British and Irish hospitals each collected up to 300 bacterial isolates from in-patients. The organisms were identified by an appropriate API system or, for staphylococci, by their Gram and coagulase reactions. Disc susceptibility tests were performed. Isolates that gave zones spp. streptococci, pneumococci and Enterococcus faecalis were susceptible to piperacillin/tazobactam (defined as giving a zone > or = 22 mm to a 75 micrograms + 10 micrograms disc), as were 86% of Acinetobacter spp. and 82% of the Citrobacter, Enterobacter, Morganella and Serratia group. Tazobactam particularly extended the activity of piperacillin against E. coli isolates (96% susceptible cf. 61% to piperacillin alone) klebsiellae (95% cf. 70%), P. mirabilis (99% cf. 86%), and Acinetobacter spp. (86% cf. 53%). Occasional (18%) resistance in Enterobacter, Serratia and Citrobacger spp. was probably caused by stable depression of Class I beta-lactamases, which are inhibited poorly by tazobactam. High resistance frequencies (> 25%) were found for Enterococcus faecium and Xanthomonas maltophilia. Tazobactam potentiated piperacillin against beta-lactamase-producing methicillin-susceptible Staphylococcus aureus, but the mode inhibition zone of piperacillin/tazobactam discs was only 26 mm, compared to 38 mm for beta-lactamase-negative isolates. Nevertheless, fewer than 5% of the enzyme producers appeared resistant to 8 + 4 mg/L piperacillin/tazobactam in MIC tests. Similar behaviour was noted for coagulase-negative staphylococci. Amongst the eleven comparator drugs, ceftazidime, gentamicin and ciprofloxacin were as active as piperacillin/tazobactam against most enterobacteria. However, Acinetobacter and Bacteroides spp. and enterococci were resistant to ceftazidime, and Bacteroides spp., enterococci, pneumococci and other streptococci were inherently resistant to ciprofloxacin and gentamicin. Cefuroxime, ampicillin and co-amoxiclav had narrower spectra. Only imipenem showed a

  1. The association of gut microbiota with body weight and body mass index in preschool children of Estonia

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    Epp Sepp

    2013-02-01

    Full Text Available Background: The gut microbiota has been shown to affect both fat storage and energy harvesting, suggesting that it plays a direct role in the development of obesity. The aim of this study was to investigate whether intestinal colonization by particular species/groups of the intestinal microbiota is related to body weight values in Estonian preschool children born in different years during the entire 1990s. Methods: Body weight, height, body mass index (BMI, and quantitative composition of cultivable gut microbiota (staphylococci, enterococci, streptococci, enterobacteria, lactobacilli, anaerobic gram-positive cocci, bifidobacteria, eubacteria, bacteroides, clostridia, and candida were studied in 51 healthy 5-year-old children (40 were born between 1993 and 94 and 11 were born between 1996 and 97. Results: At the age of 5 years, median weight was 19.5 kg and median BMI was 15.3 kg/m2. Significantly higher BMI (p=0.006 was found in 5-year-old children born in late versus early 1990s during the development of socioeconomic situation of Estonia (2% rise in gross domestic product. The counts of the different gut bacteria did not show any association with weight and BMI in the 5-year-old children. However, the BMI values were in positive correlation with a relative share of anaerobic gram-positive bacteria, for example, bifidobacteria when adjusted for sex and year of birth (adj R2=0.459, p=0.026 and eubacteria (adj R2=0.484, p=0.014 in the community of cultured intestinal microbiota. The relative share of bacteroides showed a negative correlation with the childrens’ weight (adj R2=− 0.481, p=0.015. Conclusion: The body weight indices of preschool children of the general population are associated with the proportion of anaerobic intestinal microbiota and can be predicted by sex and particular socioeconomic situation from birth to 5 years of age.

  2. Prebiotic fibres dose-dependently increase satiety hormones and alter Bacteroidetes and Firmicutes in lean and obese JCR:LA-cp rats.

    Science.gov (United States)

    Parnell, Jill A; Reimer, Raylene A

    2012-02-01

    There is a growing interest in modulating gut microbiota with diet in the context of obesity. The purpose of the present study was to evaluate the dose-dependent effects of prebiotics (inulin and oligofructose) on gut satiety hormones, energy expenditure, gastric emptying and gut microbiota. Male lean and obese JCR:LA-cp rats were randomised to either of the following: lean 0 % fibre (LC), lean 10 % fibre (LF), lean 20 % fibre (LHF), obese 0 % fibre (OC), obese 10 % fibre (OF) or obese 20 % fibre (OHF). Body composition, gastric emptying, energy expenditure, plasma satiety hormone concentrations and gut microbiota (using quantitative PCR) were measured. Caecal proglucagon and peptide YY mRNA levels were up-regulated 2-fold in the LF, OF and OHF groups and 3-fold in the LHF group. Ghrelin O-acyltransferase mRNA levels were higher in obese v. lean rats and decreased in the OHF group. Plasma ghrelin response was attenuated in the LHF group. Microbial species measured in the Bacteroidetes division decreased, whereas those in the Firmicutes increased in obese v. lean rats and improved with prebiotic intake. Bifidobacterium and Lactobacillus increased in the OHF v. OC group. Bacteroides and total bacteria negatively correlated with percentage of body fat and body weight. Enterobacteriaceae increased in conjunction with glucose area under the curve (AUC) and glucagon-like peptide-1 AUC. Bacteroides and total bacteria correlated positively with ghrelin AUC yet negatively with insulin AUC and energy intake (P alterations in gut microbiota) are regulated in a dose-dependent manner. The combined effects of prebiotics may have therapeutic potential for obesity. PMID:21767445

  3. 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.

  4. Application of empirical predictive modeling using conventional and alternative fecal indicator bacteria in eastern North Carolina waters

    Science.gov (United States)

    Gonzalez, Raul; Conn, Kathleen E.; Crosswell, Joey; Noble, Rachel

    2012-01-01

    Coastal and estuarine waters are the site of intense anthropogenic influence with concomitant use for recreation and seafood harvesting. Therefore, coastal and estuarine water quality has a direct impact on human health. In eastern North Carolina (NC) there are over 240 recreational and 1025 shellfish harvesting water quality monitoring sites that are regularly assessed. Because of the large number of sites, sampling frequency is often only on a weekly basis. This frequency, along with an 18–24 h incubation time for fecal indicator bacteria (FIB) enumeration via culture-based methods, reduces the efficiency of the public notification process. In states like NC where beach monitoring resources are limited but historical data are plentiful, predictive models may offer an improvement for monitoring and notification by providing real-time FIB estimates. In this study, water samples were collected during 12 dry (n = 88) and 13 wet (n = 66) weather events at up to 10 sites. Statistical predictive models for Escherichiacoli (EC), enterococci (ENT), and members of the Bacteroidales group were created and subsequently validated. Our results showed that models for EC and ENT (adjusted R2 were 0.61 and 0.64, respectively) incorporated a range of antecedent rainfall, climate, and environmental variables. The most important variables for EC and ENT models were 5-day antecedent rainfall, dissolved oxygen, and salinity. These models successfully predicted FIB levels over a wide range of conditions with a 3% (EC model) and 9% (ENT model) overall error rate for recreational threshold values and a 0% (EC model) overall error rate for shellfish threshold values. Though modeling of members of the Bacteroidales group had less predictive ability (adjusted R2 were 0.56 and 0.53 for fecal Bacteroides spp. and human Bacteroides spp., respectively), the modeling approach and testing provided information on Bacteroidales ecology. This is the first example of a set of successful statistical

  5. 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

  6. 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

  7. ISOLATION OF ANAEROBES IN DEEP SEATED PRESSURE ULCERS USING A NOVEL INNOVATIVE TECHNIQUE OF ANAEROBE ISOLATION

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    Lalbiaktluangi

    2015-12-01

    Full Text Available BACKGROUND Isolation of an anaerobe is usually neglected in hospitals with limited resources due to the expensive and complicated technique of anaerobic isolation methods, which is difficult to arrange in such resource poor settings. Conventionally adopted anaerobic culture methods such as Anaerobic jar, Gas-Pak, Anoxomat or Automated glove-box systems are extremely costly and cumbersome for single unit testing, but not suitable for small scale laboratories. However, anaerobic bacteria are not to be overlooked as they have made a comeback in clinical settings and are even showing resistance to Metronidazole, once thought to be the gold standard bullet against anaerobes. Deep seated pressure ulcers are usually the site where anaerobe causes an infection in synergy with aerobes. AIMS AND OBJECTIVES Isolation of anaerobes in deep seated pressure ulcers using a novel innovative technique and to study their antibiogram profile. MATERIALS AND METHODS Swabs taken from depth of deep seated pressure ulcers were immediately inoculated in Brucella blood agar at bedside and placed in polycarbonate airtight jar for anaerobic incubation using a novel innovative Modified Candle Jar technique. In this technique five grams of grease-free grade zero steel wool were dipped in 50ml freshly prepared acidified copper sulphate solution until the copper colour appeared. Excess solution was drained and the steel wool was moulded into a loose pad to fit on an open Petri plate placed on top of the inoculated Brucella blood agar plates. A white-wax candle was placed at the centre of this plate. A small test tube containing mixture of 0.5g sodium-bicarbonate and 0.5g magnesium carbonate was kept ready to be placed inside the jar, just after placing the inoculated plate and incubated for 48 hours. RESULTS Peptostreptococcus anaerobius and Bacteroides fragilis were successfully isolated from deep seated pressure ulcers by this method. Antibiogram studies were done using the

  8. The impact of hospital and urban wastewaters on the bacteriological contamination of the water resources in Kinshasa, Democratic Republic of Congo.

    Science.gov (United States)

    Kilunga, Pitchouna I; Kayembe, John M; Laffite, Amandine; Thevenon, Florian; Devarajan, Naresh; Mulaji, Crispin K; Mubedi, Josué I; Yav, Zéphirin G; Otamonga, Jean-Paul; Mpiana, Pius T; Poté, John

    2016-10-14

    Although the United Nations General Assembly recognized in 2010 the right to safe and clean drinking water and sanitation as a human right that is essential to the full enjoyment of life and all other human rights, the contamination of water supplies with faecal pathogens is still a major and unsolved problem in many parts of the world. In this study, faecal indicator bacteria (FIB), including Escherichia coli (E. coli) and Enterococcus (ENT), were quantified over the period of June/July 2014 and June/July 2015 to assess the quality of hospital effluents (n = 3: H1, H2 and H3) and of rivers receiving wastewaters from the city of Kinshasa, Democratic Republic of Congo. The water and sediment samples from the river-receiving systems were collected in, upstream and downstream of the hospital outlet pipe (HOP) discharge. The analysis of E. coli and ENT in water and sediment suspension was performed using the cultural membrane filter method. The FIB characterization was performed for general E. coli, Enterococcus faecalis(E. faecalis) and human-specific Bacteroides by PCR using specific primers. The results revealed very high FIB concentration in the hospital effluent waters, with E. coli reaching the values of 4.2 × 10(5), 16.1 × 10(5) and 5.9 × 10(5) CFU 100 mL(-1), for the hospital effluents from H1, H2, and H3, respectively; and Enterococcus reaching the values of 2.3 × 10(4), 10.9 × 10(4) and 4.1 × 10(4) CFU 100 mL(-1), respectively. Interestingly, the FIB levels in the water and sediment samples from river-receiving systems are spatially and temporally highly variable and present in some samples with higher values than the hospital effluents. The PCR assays for human-specific Bacteroides HF183/HF134 further indicate that more than 98% of bacteria were from human origin. The results of this research therefore confirm the hypothesis of our previous studies, indicating that in developing countries (e.g., Democratic Republic of Congo and South India), the

  9. BSAC standardized disc susceptibility testing method (version 8).

    Science.gov (United States)

    Andrews, J M

    2009-09-01

    azithromycin, clarithromycin, erythromycin and telithromycin (Table 15); clarithromycin and erythromycin MIC and zone diameter BPs for Moraxella catarrhalis (Table 16); azithromycin MIC BPs for Neisseria gonorrhoeae (Table 17); chloramphenicol and rifampicin MIC BPs for Neisseria meningitidis (Table 18); azithromycin MIC BPs for Haemophilus influenzae (Table 19); MIC BPs for metronidazole for Bacteroides fragilis, Bacteroides thetaiotaomicron and Clostridium perfringens (Tables 23-25, respectively); susceptibility testing of Listeria spp. (Appendix 3); the acceptable range for ATCC 25923 to a 10 microg tobramycin disc (Table 26). PMID:19587067

  10. In vitro activities of cefminox against anaerobic bacteria compared with those of nine other compounds.

    Science.gov (United States)

    Hoellman, D B; Spangler, S K; Jacobs, M R; Appelbaum, P C

    1998-03-01

    The agar dilution MIC method was used to test the activity of cefminox, a beta-lactamase-stable cephamycin, compared with those of cefoxitin, cefotetan, moxalactam, ceftizoxime, cefotiam, cefamandole, cefoperazone, clindamycin, and metronidazole against 357 anaerobes. Overall, cefminox was the most active beta-lactam, with an MIC at which 50% of isolates are inhibited (MIC50) of 1.0 microg/ml and an MIC90 of 16.0 microg/ml. Other beta-lactams were less active, with respective MIC50s and MIC90s of 2.0 and 64.0 microg/ml for cefoxitin, 2.0 and 128.0 microg/ml for cefotetan, 2.0 and 64.0 microg/ml for moxalactam, 4.0 and > 128.0 microg/ml for ceftizoxime, 16.0 and > 128.0 microg/ml for cefotiam, 8.0 and >128.0 microg/ml for cefamandole, and 4.0 and 128.0 microg/ml for cefoperazone. The clindamycin MIC50 and MIC90 were 0.5 and 8.0 microg/ml, respectively, and the metronidazole MIC50 and MIC90 were 1.0 and 4.0 microg/ml, respectively. Cefminox was especially active against Bacteroides fragilis (MIC90, 2.0 microg/ml), Bacteroides thetaiotaomicron (MIC90, 4.0 microg/ml), fusobacteria (MIC90, 1.0 microg/ml), peptostreptococci (MIC90, 2.0 microg/ml), and clostridia, including Clostridium difficile (MIC90, 2.0 microg/ml). Time-kill studies performed with six representative anaerobic species revealed that at the MIC all compounds except ceftizoxime were bactericidal (99.9% killing) against all strains after 48 h. At 24 h, only cefminox and cefoxitin at 4x the MIC and cefoperazone at 8x the MIC were bactericidal against all strains. After 12 h, at the MIC all compounds except moxalactam, ceftizoxime, cefotiam, cefamandole, clindamycin, and metronidazole gave 90% killing of all strains. After 3 h, cefminox at 2 x the MIC produced the most rapid effect, with 90% killing of all strains. PMID:9517922

  11. Comparative (Meta)genomic Analysis and Ecological Profiling of Human Gut-Specific Bacteriophage φB124-14

    Science.gov (United States)

    Ogilvie, Lesley A.; Caplin, Jonathan; Dedi, Cinzia; Diston, David; Cheek, Elizabeth; Bowler, Lucas; Taylor, Huw; Ebdon, James; Jones, Brian V.

    2012-01-01

    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 (meta)genomic, 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 ecological landscape

  12. Comparative (metagenomic analysis and ecological profiling of human gut-specific bacteriophage φB124-14.

    Directory of Open Access Journals (Sweden)

    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

  13. 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

  14. 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

  15. Ileal microbiota of growing pigs fed different dietary calcium phosphate levels and phytase content and subjected to ileal pectin infusion.

    Science.gov (United States)

    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

  16. Real-time analysis of gut flora in Entamoeba histolytica infected patients of Northern India

    Directory of Open Access Journals (Sweden)

    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

  17. Microorganisms linked to inflammatory bowel disease-associated dysbiosis differentially impact host physiology in gnotobiotic mice.

    Science.gov (United States)

    Hoffmann, Thomas W; Pham, Hang-Phuong; Bridonneau, Chantal; Aubry, Camille; Lamas, Bruno; Martin-Gallausiaux, Camille; Moroldo, Marco; Rainteau, Dominique; Lapaque, Nicolas; Six, Adrien; Richard, Mathias L; Fargier, Emilie; Le Guern, Marie-Emmanuelle; Langella, Philippe; Sokol, Harry

    2016-02-01

    Studying host-microbiota interactions are fundamental to understanding the mechanisms involved in intestinal homeostasis and inflammation. In this work, we analyzed these interactions in mice that were mono-associated with six microorganisms that are representative of inflammatory bowel disease (IBD)-associated dysbiosis: the bacteria Bacteroides thetaiotaomicron, adhesive-invasive Escherichia coli (AIEC), Ruminococcus gnavus and Roseburia intestinalis; a yeast used as a probiotic drug, Saccharomyces boulardii CNCM I-745; and another yeast, Candida albicans. Extensive ex vivo analyses including colon transcriptomics, histology, immune response, bile acid metabolism and short-chain fatty acid production were studied. We showed that B. thetaiotaomicron had the highest impact on the immune system because it was almost able to recapitulate the effects of the entire conventional microbiota and notably induced Treg pathways. Furthermore, these analyses uncovered the effects of E. coli AIEC LF82 on indoleamine 2,3-dioxygenase expression and of S. boulardii CNCM I-745 on angiogenesis. These results were confirmed in vitro in human cell lines. Finally, our results suggested that R. gnavus has major effects on metabolism, and notably on tryptophan metabolism. This work therefore reveals that microorganisms with a potential role in intestinal homeostasis and inflammation have specific impacts on the host, and it suggests several tracks to follow to understand intestinal homeostasis and IBD pathogenesis better, providing new insights to identify novel therapeutic targets. PMID:26218241

  18. The host and the flora.

    Science.gov (United States)

    Nuding, S; Antoni, L; Stange, E F

    2013-01-01

    To prevent bacterial overgrowth, colonization of the epithelium and subsequent translocation, the gastrointestinal tract maintains an effective mucosal barrier. Besides mucus the most important components of this protective system are epithelial antimicrobial peptides such as defensins, the cathelicidin LL-37, lysozyme, phospholipase A, and proteins with additional antimicrobial properties such as ubiquicidin, ribosomal proteins or histones. Commensal species may tolerate intestinal antimicrobial peptides, for example Bacteroides ssp. or Parabacteroides ssp. as major species in the human colon were highly resistant to the constitutive defensin HBD-1 and only susceptible to the inducible defensin HBD-3. Reduction of disulfide bonds is an important mechanism activating HBD-1. As several studies show, alterations in the expression of antimicrobial peptides directly influence the composition of the intestinal flora. Correspondingly, an increased production of defensins or inhibition of the processing of mouse defensins to their active form led to a quantitative shift of luminal and mucosal bacterial species. On the other hand, microorganisms also modulate the synthesis of host defensins by induction or inhibition of specific peptides. Lactobacilli, the probiotic strain Escherichia coli Nissle and Salmonella enteritica stimulate HBD-2 expression, whereas Shigella flexneri downregulates the synthesis of HBD-1, HBD-3 and LL-37. Thus, the proper balance between the luminal flora and the mucosa is a permanently dynamic, sensitive and host-specific relationship. PMID:24246976

  19. Elevated IgG levels against specific bacterial antigens in obese patients with diabetes and in mice with diet-induced obesity and glucose intolerance.

    Science.gov (United States)

    Mohammed, Nadeem; Tang, Lihua; Jahangiri, Anisa; de Villiers, Willem; Eckhardt, Erik

    2012-09-01

    High fat diets increase the risk for insulin resistance by promoting inflammation. The cause of inflammation is unclear, but germfree mouse studies have implicated commensal gut bacteria. We tested whether diet-induced obesity, diabetes, and inflammation are associated with anti-bacterial IgG. Blood from lean and obese healthy volunteers or obese patients with diabetes were analyzed by ELISA for IgG against extracts of potentially pathogenic and pro-biotic strains of Escherichia coli (LF-82 and Nissle), Bacteroides thetaiotaomicron, and Lactobacillus acidophilus, and for circulating tumor necrosis factor α (TNFα). C57Bl/6 mice were fed low- or high-fat diets (10% or 60% kcal from fat) for 10 weeks and tested for anti-bacterial IgG, bodyweight, fasting glucose, and inflammation. Obese diabetic patients had significantly more IgG against extracts of E. coli LF-82 compared with lean controls, whereas IgG against extracts of the other bacteria was unchanged. Circulating TNFα was elevated and correlated with IgG against the LF-82 extract. Mice fed high-fat diets had increased fasting glucose levels, elevated TNFα and neutrophils, and significantly more IgG against the LF-82 extracts. Diabetes in obesity is characterized by increased IgG against specific bacterial antigens. Specific commensal bacteria may mediate inflammatory effects of high-fat diets. PMID:22424821

  20. Development of microbial trigger based oral formulation of Tinidazole and its Gamma Scintigraphy Evaluation: A promising tool against anaerobic microbes associated GI problems.

    Science.gov (United States)

    Sharma, Braj Gaurav; Kumar, Neeraj; Nishad, Dhruv Kumar; Khare, Naveen K; Bhatnagar, Aseem

    2016-06-30

    Tinidazole is a versatile anti-amoebic and anti-anaerobic drug used in treatment of intestinal infection. The aim of present study was to develop and evaluate a guar gum based novel target release Tinidazole matrix tablet in animal models and healthy human volunteer using Gamma Scintigraphy technique. Anti-anaerobic and anti-protozoal activity of the developed formulation was studied in vitro against Bacteroides fragilis and Dentamoeba fragilis. Tinidazole was successful radiolabelled with (99m)Tc-pertechnetate using stannous chloride as a reducing agent and stable up to 24h in normal saline and serum. Radiolabeled formulation was evaluated in 6 Newzealand white rabbits by gamma Scintigraphy in static manner up to 24h for its retention in gastrointestinal tract (GIT). Similar set of study was conducted in 12 healthy human volunteers for similar objective Scintigraphy images of healthy human volunteer showed retention of optimized formulations in stomach up to 60min, from where it moved to duodenum further and reached ileum in around 5h. However, initiation of drug release was observed from intestine at 7h. Complete dissociation and release of drug was observed at 24h in colon due to anaerobic microbial rich environment. Results drawn from Scintigraphy images indicate that radiolabeled (99m)Tc-Tinidazole tablet transit through upper part of GI without disintegration. Hence the developed matrix tablet may have a role in treatment of intestinal infection caused by anaerobic bacteria. PMID:27108116

  1. In vitro fermentability and prebiotic potential of soyabean Okara by human faecal microbiota.

    Science.gov (United States)

    Pérez-López, E; Cela, D; Costabile, A; Mateos-Aparicio, I; Rupérez, P

    2016-09-01

    At present, there is a huge interest in finding new prebiotics from agrofood industrial waste, such as the soyabean by-product Okara, rich in insoluble dietary fibre. A previous treatment of Okara with high hydrostatic pressure assisted by the food-grade enzyme Ultraflo ® L achieved a 58·2 % increment in its soluble dietary fibre (SDF) contents. Therefore, potential prebiotic effect of both treated and native Okara was assayed using 48 h, pH-controlled, anaerobic batch cultures inoculated with human faecal slurries, which simulate the human gut. Changes in faecal microbiota were evaluated using 16S rRNA-based fluorescence in situ hybridisation, whereas release of SCFA and lactic acid was assessed by HPLC. Both Okara samples exhibited potential prebiotic effects but Okara treated to maximise its SDF content showed higher SCFA plus lactic acid, better growth promotion of beneficial bacteria, including bifidobacteria after 4 and 48 h and lactobacilli after 4 h of fermentation, and a greater inhibition of potentially harmful bacterial groups such as clostridia and Bacteroides. Differences found between fructo-oligosaccharides and Okara substrates could be attributed to the great complexity of Okara's cell wall, which would need longer times to be fermented than other easily digested molecules, thus allowing an extended potential prebiotic effect. These results support an in vitro potential prebiotic effect of Okara. PMID:27469454

  2. Sepsis in preterm infants causes alterations in mucosal gene expression and microbiota profiles compared to non-septic twins.

    Science.gov (United States)

    Cernada, María; Bäuerl, Christine; Serna, Eva; Collado, Maria Carmen; Martínez, Gaspar Pérez; Vento, Máximo

    2016-01-01

    Sepsis is a life-threatening condition in preterm infants. Neonatal microbiota plays a pivotal role in the immune system maturation. Changes in gut microbiota have been associated to inflammatory disorders; however, a link with sepsis in the neonatal period has not yet been established. We aimed to analyze gut microbiota and mucosal gene expression using non-invasively obtained samples to provide with an integrative perspective of host-microbe interactions in neonatal sepsis. For this purpose, a prospective observational case-control study was conducted in septic preterm dizygotic twins and their non-septic twin controls. Fecal samples were used for both microbiota analysis and host genome-wide expression using exfoliated intestinal cells. Gene expression of exfoliated intestinal cells in septic preterm showed an induction of inflammatory and oxidative stress pathways in the gut and pro-oxidant profile that caused dysbiosis in the gut microbiota with predominance of Enterobacteria and reduction of Bacteroides and Bifidobacterium spp.in fecal samples, leading to a global reduction of beneficial anaerobic bacteria. Sepsis in preterm infants induced low-grade inflammation and oxidative stress in the gut mucosa, and also changes in the gut microbiota. This study highlights the role of inflammation and oxidative stress in neonatal sepsis on gut microbial profiles. PMID:27180802

  3. Significant pharmacokinetic differences of berberine are attributable to variations in gut microbiota between Africans and Chinese.

    Science.gov (United States)

    Alolga, Raphael N; Fan, Yong; Chen, Zhuo; Liu, Li-Wei; Zhao, Yi-Jing; Li, Jin; Chen, Yan; Lai, Mao-De; Li, Ping; Qi, Lian-Wen

    2016-01-01

    We investigated the influence of gut microbiotal metabolism on the pharmacokinetics of berberine in healthy male Africans and Chinese. The Cmax and AUC in the Africans were 2.67-fold and 2.0-fold higher than the Chinese, respectively. Microbiotal compositions by 16S rRNA pyrosequencing showed higher abundance of the genera Prevotella, Bacteroides, and Megamonas (34.22, 13.88, and 10.68%, respectively) in the Chinese than the Africans (30.08, 9.43, and 0.48%, respectively). Scatter plot showed a strong negative correlation between the microbiotal abundance and the berberine AUC, especially for the genus Prevotella (r = -0.813) and its species. A more extensive metabolism was observed in Chinese with 1.83-fold higher metabolites, possibly contributing to the lower AUC than the Africans. In conclusion, significant PK differences of berberine were observed between Africans and Chinese, which is partly attributable to variations in gut microbiota and its corresponding metabolic capacity. PMID:27283523

  4. Use of antibiotics in the management of postirradiation wound infection and sepsis

    International Nuclear Information System (INIS)

    Ionizing gamma irradiation depresses the host defenses and enhances the susceptibility of the immunocompromised host to local and systemic infection due to endogenous or exogenous microorganisms. Trauma and wounding act synergistically and decrease the survival after exposure to irradiation. The current antimicrobial agents suitable for controlling serious infections and their use in post irradiation local and systemic infection with and without trauma are discussed. The experience gained in managing immunocompromised patients following chemotherapy is reviewed. Empiric single agent or combination agent therapy should be directed at the eradication of potential gram-negative as well as gram-positive pathogens. The most important organisms known to cause these infections are Pseudomonas sp. and Enterobacteriaceae. Management of intra-abdominal infections following trauma should include early surgical correlation and antimicrobials directed against the Bacteroides fragilis group and Enterobacteriaceae. Staphylococcus aureus and Streptococcus pyogenes cause most skin and soft tissue infections following trauma. Chemoprophylaxis of enteric sources of systemic infection can be achieved by antimicrobials that selectively inhibit the Enterobacteriaceae sp. and preserve the anaerobic flora. The management of infection in the injured and irradiated host includes supportive and restorative therapy. Supportive therapy includes debridement and cleansing of wounds, fluids, immunoglobulin, and antimicrobials. Restorative therapy includes definite surgery repair and replenishment of the immune system by use of immunomodulators, growth factors, and bone marrow transplantation. Further studies are needed to examine the usefulness of presently available drugs and experimental agents in the irradiated and traumatized host. 111 references

  5. Drought Stress Responses in Soybean Roots and Nodules

    Science.gov (United States)

    Kunert, Karl J.; Vorster, Barend J.; Fenta, Berhanu A.; Kibido, Tsholofelo; Dionisio, Giuseppe; Foyer, Christine H.

    2016-01-01

    Drought is considered to be a major threat to soybean production worldwide and yet our current understanding of the effects of drought on soybean productively is largely based on studies on above-ground traits. Although the roots and root nodules are important sensors of drought, the responses of these crucial organs and their drought tolerance features remain poorly characterized. The symbiotic interaction between soybean and rhizobia facilitates atmospheric nitrogen fixation, a process that provides essential nitrogen to support plant growth and development. Symbiotic nitrogen fixation is important for sustainable agriculture, as it sustains plant growth on nitrogen-poor soils and limits fertilizer use for crop nitrogen nutrition. Recent developments have been made in our understanding of the drought impact on soybean root architecture and nodule traits, as well as underpinning transcriptome, proteome and also emerging metabolome information, with a view to improve the selection of more drought-tolerant soybean cultivars and rhizobia in the future. We conclude that the direct screening of root and nodule traits in the field as well as identification of genes, proteins and also metabolites involved in such traits will be essential in order to gain a better understanding of the regulation of root architecture, bacteroid development and lifespan in relation to drought tolerance in soybean. PMID:27462339

  6. Differential Susceptibility of Bacteria to Mouse Paneth Cell a-Defensins under Anaerobic Conditions

    Directory of Open Access Journals (Sweden)

    Jennifer R. Mastroianni

    2014-10-01

    Full Text Available Small intestinal Paneth cells secrete a-defensin peptides, termed cryptdins (Crps in mice, into the intestinal lumen, where they confer immunity to oral infections and define the composition of the ileal microbiota. In these studies, facultative bacteria maintained under aerobic or anaerobic conditions displayed differential sensitivities to mouse a-defensins under in vitro assay conditions. Regardless of oxygenation, Crps 2 and 3 had robust and similar bactericidal activities against S. typhimurium and S. flexneri, but Crp4 activity against S. flexneri was attenuated in the absence of oxygen. Anaerobic bacteria varied in their susceptibility to Crps 2-4, with Crp4 showing less activity than Crps 2 and 3 against Enterococcus faecalis, and Bacteroides fragilis in anaerobic assays, but Fusobacterium necrophorum was killed only by Crp4 and not by Crps 2 and 3. The influence of anaerobiosis in modulating Crp bactericidal activities in vitro suggests that a-defensin effects on the enteric microbiota may be subject to regulation by local oxygen tension.

  7. Phylogenetic diversity of bacteria associated with Paleolithic paintings and surrounding rock walls in two Spanish caves (Llonín and La Garma).

    Science.gov (United States)

    Schabereiter-Gurtner, Claudia; Saiz-Jimenez, Cesareo; Piñar, Guadalupe; Lubitz, Werner; Rölleke, Sabine

    2004-02-01

    Bacterial diversity in caves is still rarely investigated using culture-independent techniques. In the present study, bacterial communities on Paleolithic paintings and surrounding rock walls in two Spanish caves (Llonín and La Garma) were analyzed, using 16S rDNA-based denaturing gradient gel electrophoresis community fingerprinting and phylogenetic analyses without prior cultivation. Results revealed complex bacterial communities consisting of a high number of novel 16S rDNA sequence types and indicated a high biodiversity of lithotrophic and heterotrophic bacteria. Identified bacteria were related to already cultured bacteria (39 clones) and to environmental 16S rDNA clones (46 clones). The nearest phylogenetic relatives were members of the Proteobacteria (41.1%), of the Acidobacterium division (16.5%), Actinobacteria (20%), Firmicutes (10.6%), of the Cytophaga/Flexibacter/Bacteroides division (5.9%), Nitrospira group (3.5%), green non-sulfur bacteria (1.2%), and candidate WS3 division (1.2%). Thirteen of these clones were most closely related to those obtained from the previous studies on Tito Bustillo Cave. The comparison of the present data with the data obtained previously from Altamira and Tito Bustillo Caves revealed similarities in the bacterial community components, especially in the high abundance of the Acidobacteria and Rhizobiaceae, and in the presence of bacteria related to ammonia and sulfur oxidizers. PMID:19712338

  8. Vertical quantitative and dominant population distribution of the bacteria isolated from the Muztagata ice core

    Institute of Scientific and Technical Information of China (English)

    XIANG; Shurong; YAO; Tandong; AN; Lizhe; WU; Guangjian; XU

    2005-01-01

    Vertical distribution of the main bacteria isolated from the Muztagata ice core (about 22.4 m) was investigated by means of cultivation and 16S rRNA sequence analysis. The results showed that the amount of culturable bacteria fluctuated with ice core depth, and was more in dirty layer than in clean ice, which suggested the close corresponding relationship between high input of the bacteria deposited by wind and snowflow and dirty layer. Most of the bacteria were psychrophiles and psychrotolerants, including α- and γ-proteobacteria, Cryobacterium psychrophilum, CFB (Cytophaga-Flavobacterium-Bacteroides) group, high-G+C gram-positive bacteria (HGC). Acinetobacter sp. And HGC repeatly occurred in different ice depths, and their quantitative distribution was consistent with the change of the total amount of culturable bacteria with depth, which suggested the main bio-indicator; while Flavobacterium, Cryobacterium psychrophilum, and α-proteobacteria, also functioned as a secondary indicator of climatic and environmental changes. This study is the first report concerning continuous quantitative variation and pattern of the main culturable bacteria in ice core section.

  9. Bacterial community in deep subseafloor sediments from the western Pacific "warm pool"

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    The bacterial community in deep subseafloor sediments at a depth of 230 cm from the western Pacific "warm pool" is studied by construction of 16S rDNA clone library and PCR-RFLP (Restriction Fragment Length Polymorphism) analysis. The results indicate that the bacterial community in these sediments is mainly composed of five groups: α-Proteobacteria, β-Proteobacteria, CFB group (Cytophaga / Flexi-bacteria / Bacteroides), Acidobacteria and gram positive bacteria, with a few genera detected in each group. The most abundant bacteria group is α-Proteobacteria, and the next is β-Proteobacteria. The dominant species in α-and β-Proteobacteria are Sphingomonas paucimobilis and Pseudomonas alca-ligenes respectively. The CFB group is simply composed of members belonging to Flavobacterium. The gram positive bacteria are rich, and mainly consists of the genus Geobacillus. The analysis of bacterial community indicates that organic matter is still abundant in the subseafloor sediments at the depth of 230 cm in the western Pacific "warm pool" . These bacteria in this deep biosphere may play an impor-tant role in the nitrogen cycle of deep sea sediments at "warm pool" .

  10. A microfluidics-based in vitro model of the gastrointestinal human–microbe interface

    Science.gov (United States)

    Shah, Pranjul; Fritz, Joëlle V.; Glaab, Enrico; Desai, Mahesh S.; Greenhalgh, Kacy; Frachet, Audrey; Niegowska, Magdalena; Estes, Matthew; Jäger, Christian; Seguin-Devaux, Carole; Zenhausern, Frederic; Wilmes, Paul

    2016-01-01

    Changes in the human gastrointestinal microbiome are associated with several diseases. To infer causality, experiments in representative models are essential, but widely used animal models exhibit limitations. Here we present a modular, microfluidics-based model (HuMiX, human–microbial crosstalk), which allows co-culture of human and microbial cells under conditions representative of the gastrointestinal human–microbe interface. We demonstrate the ability of HuMiX to recapitulate in vivo transcriptional, metabolic and immunological responses in human intestinal epithelial cells following their co-culture with the commensal Lactobacillus rhamnosus GG (LGG) grown under anaerobic conditions. In addition, we show that the co-culture of human epithelial cells with the obligate anaerobe Bacteroides caccae and LGG results in a transcriptional response, which is distinct from that of a co-culture solely comprising LGG. HuMiX facilitates investigations of host–microbe molecular interactions and provides insights into a range of fundamental research questions linking the gastrointestinal microbiome to human health and disease. PMID:27168102

  11. Distribution and functions of TonB-dependent transporters in marine bacteria and environments: implications for dissolved organic matter utilization.

    Directory of Open Access Journals (Sweden)

    Kai Tang

    Full Text Available BACKGROUND: Bacteria play critical roles in marine nutrient cycles by incorporating and redistributing dissolved organic matter (DOM and inorganic nutrients in the ocean. TonB-dependent transporter (TBDT proteins allow Gram-negative bacteria to take up scarce resources from nutrient-limiting environments as well as siderophores, heme, vitamin B12, and recently identified carbohydrates. Thus, the characterization of TBDT distribution and functions is essential to better understand the contribution TBDT to DOM assimilation and its consequences on nutrient cycling in the environment. METHODOLOGY/PRINCIPAL FINDINGS: This study presents the distribution of encoded known and putative TBDT proteins in the genomes of microorganisms and from the Global Ocean Survey data. Using a Lek clustering algorithm and substrate specificities, the TBDT sequences were mainly classified into the following three groups: (1 DOM transporters; (2 Siderophores/Vitamins transporters; and (3 Heme/Hemophores/Iron(heme-binding protein transporters. Diverse TBDTs were found in the genomes of oligotroph Citromicrobium bathyomarinum JL354 and Citromicrobium sp JLT1363 and were highly expressed in the stationary phase of bacterial growth. The results show that the Gammaproteobacteria and the Cytophaga-Flavobacterium-Bacteroides (CFB group bacteria accounted for the majority of the TBDT gene pool in marine surface waters. CONCLUSIONS/SIGNIFICANCE: The results of this study confirm the ecological importance of TBDTs in DOM assimilation for bacteria in marine environments owing to a wide range of substrate utilization potential in the ubiquitous Gammaproteobacteria and CFB group bacteria.

  12. Denitrification by intact soybean nodules in relation to natural 15N enrichment of nodules

    International Nuclear Information System (INIS)

    The natural 15N abundance of nodules of soybeans (Glycine max (L.) Merrill) which are actively fixing N2 is considerably higher than other tissues. To investigate the question of whether isotopic fractionation associated with denitrification by bacteroids causes this 15N enrichment, we inoculated soybeans with two strains of Rhizobium japonicum. Free-living cultures of one of these (strain USDA 33) were unable to denitrify or respire NO3-, while free-living cultures of the second (strain USDA 138) were capable of denitrification. USDA 138 formed nodules which fixed N2 very efficiently. The N of these nodules was enriched in 15N and the nodules reduced a substantial amount of NO3- to NO2- and N2O. Nodules infected with USDA 33 fixed about half as much N2 as those infected with USDA 138. The former nodules were enriched in 15N (although less so than nodules infected with USDA 138), despite the fact that the nodules formed by USDA 33 did not reduce NO3-. Clearly denitrification could not have been the cause of 15N enrichment of nodules infected with strain USDA 33. Alternative causes of 15N enrichment of soybean nodules and their possible metabolic significance are discussed

  13. [Colonic microbial biocenosis in rheumatoid arthritis].

    Science.gov (United States)

    Gul'neva, M Iu; Noskov, S M

    2011-01-01

    The aim of the work was to study colonic microbial biocenosis and colonizing ability of opportunistic bacteria in 32 patients with rheumatoid arthritis (RA) and 30 healthy subjects. RA was diagnosed based on the American Rheumatism Association criteria (1987). Qualitative and quantitative composition of the microflora was detected by a bacteriological method. StatSoft Statistics 6.0 was used to treat the data obtained. RA was associated with significant modification of the intestinal flora, viz. decrease in lactobacteria and significant increase of enterococci, clostridia, colibacteria showing reduced enzymatic activity, and opportunistic species. Also, symbiotic relationships between microorganisms altered. The fraction of bifidobacteria, bacteroids, and lactopositive colibacteria reduced while the abundance of opportunistic enterobacteria and staphylococci was elevated. Opportunistic Enterobacteriaceae were present in urine and nasal mucosa which suggested their translocation from the intestines. It is concluded that changes in intestinal microflora and colonization by opportunistic bacteria enhance the risk of development of co-morbid conditions in patients with RA. PMID:21932563

  14. Cefoxitin and Cephalothin: Antimicrobial Activity, Human Pharmacokinetics, and Toxicology

    Science.gov (United States)

    Brumfitt, William; Kosmidis, John; Hamilton-Miller, Jeremy M. T.; Gilchrist, James N. G.

    1974-01-01

    Cefoxitin, a semisynthetic cephamycin, has been compared with the widely used parenteral cephalosporin, cephalothin, in terms of antibacterial activity, human pharmacokinetics, and toxicity. For both compounds, minimal inhibitory concentrations were within the therapeutic range against the 156 gram-positive cocci tested (except group D streptococci), but cephalothin was 8 to 20 times more active. Regarding the 313 gram-negative organisms tested, both antibiotics were of approximately equal activity against cephalothin-susceptible strains, but cefoxitin was outstandingly superior against Providencia spp. and indole-producing Proteus spp., and markedly better against Serratia marcescens and Bacteroides fragilis. Against these organisms, cefoxitin but not cephalothin would be expected to be therapeutically valuable. Antibiotic activity levels in the serum and urine of 18 human volunteers after parenteral administration were higher and more prolonged in the case of cefoxitin, which had an average terminal serum half-life of about 45 min and a urinary recovery of about 90%. Cefoxitin was entirely nontoxic and, given intramuscularly, slightly less painful then cephalothin. These preliminary results suggest that cephamycins may prove to be a significant chemotherapeutic advance. PMID:15830475

  15. Ethanol Production by Selected Intestinal Microorganisms and Lactic Acid Bacteria Growing under Different Nutritional Conditions.

    Science.gov (United States)

    Elshaghabee, Fouad M F; Bockelmann, Wilhelm; Meske, Diana; de Vrese, Michael; Walte, Hans-Georg; Schrezenmeir, Juergen; Heller, Knut J

    2016-01-01

    To gain some specific insight into the roles microorganisms might play in non-alcoholic fatty liver disease (NAFLD), some intestinal and lactic acid bacteria and one yeast (Anaerostipes caccae, Bacteroides thetaiotaomicron, Bifidobacterium longum, Enterococcus fecalis, Escherichia coli, Lactobacillus acidophilus, Lactobacillus fermentum, Lactobacillus plantarum, Weissella confusa, Saccharomyces cerevisiae) were characterized by high performance liquid chromatography for production of ethanol when grown on different carbohydrates: hexoses (glucose and fructose), pentoses (arabinose and ribose), disaccharides (lactose and lactulose), and inulin. Highest amounts of ethanol were produced by S. cerevisiae, L. fermentum, and W. confusa on glucose and by S. cerevisiae and W. confusa on fructose. Due to mannitol-dehydrogenase expressed in L. fermentum, ethanol production on fructose was significantly (P fermentative, mannitol-dehydrogenase negative lactic acid bacterium, may promote NAFLD through ethanol produced from sugar fermentation, while other intestinal bacteria and homo- and hetero-fermentative but mannitol-dehydrogenase positive lactic acid bacteria may not promote NAFLD. Also, our studies indicate that dietary factors interfering with gastrointestinal microbiota and microbial metabolism may be important in preventing or promoting NAFLD. PMID:26858714

  16. Electricity generation from cattle dung using microbial fuel cell technology during anaerobic acidogenesis and the development of microbial populations.

    Science.gov (United States)

    Zhao, Guang; Ma, Fang; Wei, Li; Chua, Hong; Chang, Chein-Chi; Zhang, Xiao-Jun

    2012-09-01

    A microbial fuel cell (MFC) was constructed to investigate the possible generation of electricity using cattle dung as a substrate. After 30 days of operation, stable electricity was generated, and the maximum volumetric power density was 0.220 W/m(3). The total chemical oxygen demand (TCOD) removal and coulombic efficiency (CE) of the MFC reached 73.9±1.8% and 2.79±0.6%, respectively, after 120 days of operation. Acetate was the main metabolite in the anolyte, and other volatile fatty acids (VFAs) (propionate and butyrate) were present in minor amounts. The PCR-DGGE analysis indicated that the following five groups of microbes were present: Proteobacteria, Bacteroides, Chloroflexi, Actinobacteria and Firmicutes. Proteobacteria and Firmicutes were the dominant phyla in the sample; specifically, 36.3% and 24.2% of the sequences obtained were Proteobacteria and Firmicutes, respectively. Clostridium sp., Pseudomonas luteola and Ochrobactrum pseudogrignonense were the most dominant groups during the electricity generation process. The diversity of archaea dramatically decreased after 20 days of operation. The detected archaea were hydrogenotrophic methanogens, and the Methanobacterium genus disappeared during the periods of stable electricity generation via acidogenesis. PMID:22595839

  17. Temporal distribution of bacterial community structure in the Changjiang Estuary hypoxia area and the adjacent East China Sea

    International Nuclear Information System (INIS)

    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)

  18. Molecular-based approaches to characterize coastal microbial community and their potential relation to the trophic state of Red Sea

    KAUST Repository

    Ansari, Mohd Ikram

    2015-03-11

    Molecular-based approaches were used to characterize the coastal microbiota and to elucidate the trophic state of Red Sea. Nutrient content and enterococci numbers were monitored, and used to correlate with the abundance of microbial markers. Microbial source tracking revealed the presence of >1 human-associated Bacteroides spp. at some of the near-shore sampling sites and at a heavily frequented beach. Water samples collected from the beaches had occasional exceedances in enterococci numbers, higher total organic carbon (TOC, 1.48-2.18 mg/L) and nitrogen (TN, 0.15-0.27 mg/L) than that detected in the near-shore waters. Enterococci abundances obtained from next-generation sequencing did not correlate well with the cultured enterococci numbers. The abundance of certain genera, for example Arcobacter, Pseudomonas and unclassified Campylobacterales, was observed to exhibit slight correlation with TOC and TN. Low abundance of functional genes accounting for up to 41 copies/L of each Pseudomonas aeruginosa and Campylobacter coli were detected. Arcobacter butzleri was also detected in abundance ranging from 111 to 238 copies/L. Operational taxonomic units (OTUs) associated with cyanobacteria, Prochlorococcus, Ostreococcus spp. and Gramella were more prevalent in waters that were likely impacted by urban runoffs and recreational activities. These OTUs could potentially serve as quantifiable markers indicative of the water quality.

  19. Xylitol Affects the Intestinal Microbiota and Metabolism of Daidzein in Adult Male Mice

    Science.gov (United States)

    Tamura, Motoi; Hoshi, Chigusa; Hori, Sachiko

    2013-01-01

    This study examined the effects of xylitol on mouse intestinal microbiota and urinary isoflavonoids. Xylitol is classified as a sugar alcohol and used as a food additive. The intestinal microbiota seems to play an important role in isoflavone metabolism. Xylitol feeding appears to affect the gut microbiota. We hypothesized that dietary xylitol changes intestinal microbiota and, therefore, the metabolism of isoflavonoids in mice. Male mice were randomly divided into two groups: those fed a 0.05% daidzein with 5% xylitol diet (XD group) and those fed a 0.05% daidzein-containing control diet (CD group) for 28 days. Plasma total cholesterol concentrations were significantly lower in the XD group than in the CD group (p < 0.05). Urinary amounts of equol were significantly higher in the XD group than in the CD group (p < 0.05). The fecal lipid contents (% dry weight) were significantly greater in the XD group than in the CD group (p < 0.01). The cecal microbiota differed between the two dietary groups. The occupation ratios of Bacteroides were significantly greater in the CD than in the XD group (p < 0.05). This study suggests that xylitol has the potential to affect the metabolism of daidzein by altering the metabolic activity of the intestinal microbiota and/or gut environment. Given that equol affects bone health, dietary xylitol plus isoflavonoids may exert a favorable effect on bone health. PMID:24336061

  20. Sepsis in preterm infants causes alterations in mucosal gene expression and microbiota profiles compared to non-septic twins

    Science.gov (United States)

    Cernada, María; Bäuerl, Christine; Serna, Eva; Collado, Maria Carmen; Martínez, Gaspar Pérez; Vento, Máximo

    2016-01-01

    Sepsis is a life-threatening condition in preterm infants. Neonatal microbiota plays a pivotal role in the immune system maturation. Changes in gut microbiota have been associated to inflammatory disorders; however, a link with sepsis in the neonatal period has not yet been established. We aimed to analyze gut microbiota and mucosal gene expression using non-invasively obtained samples to provide with an integrative perspective of host-microbe interactions in neonatal sepsis. For this purpose, a prospective observational case-control study was conducted in septic preterm dizygotic twins and their non-septic twin controls. Fecal samples were used for both microbiota analysis and host genome-wide expression using exfoliated intestinal cells. Gene expression of exfoliated intestinal cells in septic preterm showed an induction of inflammatory and oxidative stress pathways in the gut and pro-oxidant profile that caused dysbiosis in the gut microbiota with predominance of Enterobacteria and reduction of Bacteroides and Bifidobacterium spp.in fecal samples, leading to a global reduction of beneficial anaerobic bacteria. Sepsis in preterm infants induced low-grade inflammation and oxidative stress in the gut mucosa, and also changes in the gut microbiota. This study highlights the role of inflammation and oxidative stress in neonatal sepsis on gut microbial profiles. PMID:27180802

  1. Managing Microbial Risks from Indirect Wastewater Reuse for Irrigation in Urbanizing Watersheds.

    Science.gov (United States)

    Verbyla, Matthew E; Symonds, Erin M; Kafle, Ram C; Cairns, Maryann R; Iriarte, Mercedes; Mercado Guzmán, Alvaro; Coronado, Olver; Breitbart, Mya; Ledo, Carmen; Mihelcic, James R

    2016-07-01

    Limited supply of clean water in urbanizing watersheds creates challenges for safely sustaining irrigated agriculture and global food security. On-farm interventions, such as riverbank filtration (RBF), are used in developing countries to treat irrigation water from rivers with extensive fecal contamination. Using a Bayesian approach incorporating ethnographic data and pathogen measurements, quantitative microbial risk assessment (QMRA) methods were employed to assess the impact of RBF on consumer health burdens for Giardia, Cryptosporidium, rotavirus, norovirus, and adenovirus infections resulting from indirect wastewater reuse, with lettuce irrigation in Bolivia as a model system. Concentrations of the microbial source tracking markers pepper mild mottle virus and HF183 Bacteroides were respectively 2.9 and 5.5 log10 units lower in RBF-treated water than in the river water. Consumption of lettuce irrigated with river water caused an estimated median health burden that represents 37% of Bolivia's overall diarrheal disease burden, but RBF resulted in an estimated health burden that is only 1.1% of this overall diarrheal disease burden. Variability and uncertainty associated with environmental and cultural factors affecting exposure correlated more with QMRA-predicted health outcomes than factors related to disease vulnerability. Policies governing simple on-farm interventions like RBF can be intermediary solutions for communities in urbanizing watersheds that currently lack wastewater treatment. PMID:26992352

  2. Crystal structures of the BsPif1 helicase reveal that a major movement of the 2B SH3 domain is required for DNA unwinding.

    Science.gov (United States)

    Chen, Wei-Fei; Dai, Yang-Xue; Duan, Xiao-Lei; Liu, Na-Nv; Shi, Wei; Li, Na; Li, Ming; Dou, Shou-Xing; Dong, Yu-Hui; Rety, Stephane; Xi, Xu-Guang

    2016-04-01

    Pif1 helicases are ubiquitous members of the SF1B family and are essential for maintaining genome stability. It was speculated that Pif1-specific motifs may fold in specific structures, conferring distinct activities upon it. Here, we report the crystal structures of the Pif1 helicase fromBacteroides sppwith and without adenosine triphosphate (ATP) analog/ssDNA. BsPif1 shares structural similarities with RecD2 and Dda helicases but has specific features in the 1B and 2B domains. The highly conserved Pif1 family specific sequence motif interacts with and constraints a putative pin-loop in domain 1B in a precise conformation. More importantly, we found that the 2B domain which contains a specific extended hairpin undergoes a significant rotation and/or movement upon ATP and DNA binding, which is absolutely required for DNA unwinding. We therefore propose a mechanism for DNA unwinding in which the 2B domain plays a predominant role. The fact that the conformational change regulates Pif1 activity may provide insight into the puzzling observation that Pif1 becomes highly processive during break-induced replication in association with Polδ, while the isolated Pif1 has low processivity. PMID:26809678

  3. Biomethanation and microbial community changes in a digester treating sludge from a brackish aquaculture recirculation system.

    Science.gov (United States)

    Zhang, Xuedong; Tao, Yu; Hu, Jianmei; Liu, Gang; Spanjers, Henri; van Lier, Jules B

    2016-08-01

    Using a high-salinity-adapted inoculum and a moderate stepwise-increased organic loading rate (OLR), a stable digester performance was achieved in treating sludge from a brackish aquaculture recirculation system. The specific methane yield was distinctly enhanced, reaching 0.203LCH4/gCODadded, compared to literature values (0.140-0.154LCH4/gCODadded) from the salty sludges. OLR adjustment and the fecal substrate substantially influenced population changes in the digester. Within the bacterial subpopulations, the relative abundance of Bacillus and Bacteroides declined, accompanied by the increase of Clostridium and Trigonala over time. The results show Trigonala was derived from the substrate and accumulated inside the digester. The most abundant methanogen was Methanosarcina in the inoculum and the digestates. The Methanosarcina proliferation can be ascribed to its metabolic versatility, probably a feature of crucial importance for high-salinity environments. Other frequently observed methanogens were outcompeted. The population similarity at the genus level between inoculum and digestates declined during the initial stage and afterwards increased. PMID:27155261

  4. Arsenic Metabolism and Toxicity Influenced by Ferric Iron in Simulated Gastrointestinal Tract and the Roles of Gut Microbiota.

    Science.gov (United States)

    Yu, Haiyan; Wu, Bing; Zhang, Xu-Xiang; Liu, Su; Yu, Jing; Cheng, Shupei; Ren, Hong-Qiang; Ye, Lin

    2016-07-01

    Iron (Fe) is a common trace element in drinking water. However, little is known about how environmental concentrations of Fe affect the metabolism and toxicity of arsenic (As) in drinking water. In this study, influence of Fe at drinking water-related concentrations (0.1, 0.3, and 3 mg Fe (total)/L) on As metabolism and toxicity, and the roles of gut microbiota during this process were investigated by using in vitro Simulator of the Human Intestinal Microbial Ecosystem (SHIME). Results showed that Fe had ability to decrease bioaccessible As by coflocculation in small intestine. 0.1 and 0.3 mg/L Fe significantly increased As methylation in simulated transverse and descending colon. Gut microbiota played an important role in alteration of As species, and Fe could affect As metabolism by changing the gut microbiota. Bacteroides, Clostridium, Alistipes, and Bilophila had As resistance and potential ability to methylate As. Cytotoxicity assays of effluents from simulated colons showed that the low levels of Fe decreased As toxicity on human hepatoma cell line HepG2, which might be due to the increase of methylated As. When assessing the health risk of As in drinking water, the residual Fe should be considered. PMID:27280682

  5. DETECCIÓN DE FACTORES NOD EN. B. elkanii ICA 8001. INFLUENCIA DEL MEDIO DE CULTIVO

    Directory of Open Access Journals (Sweden)

    María C. Nápoles García

    2014-01-01

    Full Text Available Los factores de nodulación, sintetizados por diferentes especies de la familia Rizobiaceae, han sido descritos como señales esenciales en la interacción con plantas leguminosas. Ellos constituyen morfógenos que inducen el desarrollo de nódulos en la planta, permitiendo la entrada de las bacterias a las raíces y han demostrado tener una influencia positiva en el posterior desarrollo de los bacteroides y la eficiencia de la fijación del nitrógeno. Este trabajo está relacionado con la detección, mediante dos técnicas cromatográficas, de la producción de factores Nod por la cepa Bradyrhizobium elkanii ICA 8001, cultivada en diferentes medios; así como el efecto biológico de los inóculos obtenidos en interacción con la planta. Ambos métodos cromatográficos demostraron que la composición del medio de cultivo induce, en mayor o menor cantidad, el número de estructuras de factores Nod producidos por esta bacteria. Además, que inoculantes obtenidos a partir de diferentes composiciones de medio, inducen una nodulación diferenciada sobre plantas de soya.

  6. Inhibition of GlcNAc-Processing Glycosidases by C-6-Azido-NAG-Thiazoline and Its Derivatives

    Directory of Open Access Journals (Sweden)

    Jana Krejzová

    2014-03-01

    Full Text Available NAG-thiazoline is a strong competitive inhibitor of GH20 β-N-acetyl- hexosaminidases and GH84 β-N-acetylglucosaminidases. Here, we focused on the design, synthesis and inhibition potency of a series of new derivatives of NAG-thiazoline modified at the C-6 position. Dimerization of NAG-thiazoline via C-6 attached triazole linkers prepared by click chemistry was employed to make use of multivalency in the inhibition. Novel compounds were tested as potential inhibitors of β-N-acetylhexosaminidases from Talaromyces flavus, Streptomyces plicatus (both GH20 and β-N-acetylglucosaminidases from Bacteroides thetaiotaomicron and humans (both GH84. From the set of newly prepared NAG-thiazoline derivatives, only C-6-azido-NAG-thiazoline displayed inhibition activity towards these enzymes; C-6 triazole-substituted NAG-thiazolines lacked inhibition activity against the enzymes used. Docking of C-6-azido-NAG-thiazoline into the active site of the tested enzymes was performed. Moreover, a stability study with GlcNAc-thiazoline confirmed its decomposition at pH < 6 yielding 2-acetamido-2-deoxy-1-thio-α/β-D-glucopyranoses, which presumably dimerize oxidatively into S-S linked dimers; decomposition products of NAG-thiazoline are void of inhibitory activity.

  7. Gut microbiota composition and Clostridium difficile infection in hospitalized elderly individuals: a metagenomic study

    Science.gov (United States)

    Milani, Christian; Ticinesi, Andrea; Gerritsen, Jacoline; Nouvenne, Antonio; Lugli, Gabriele Andrea; Mancabelli, Leonardo; Turroni, Francesca; Duranti, Sabrina; Mangifesta, Marta; Viappiani, Alice; Ferrario, Chiara; Maggio, Marcello; Lauretani, Fulvio; De Vos, Willem; van Sinderen, Douwe; Meschi, Tiziana; Ventura, Marco

    2016-01-01

    The gut microbiota composition of elderly hospitalized patients with Clostridium difficile infection (CDI) exposed to previous antibiotic treatment is still poorly investigated. The aim of this study was to compare the microbiota composition by means of 16S rRNA microbial profiling among three groups of hospitalized elderly patients (age ≥ 65) under standard diet including 25 CDI-positive (CDI group), 29 CDI-negative exposed to antibiotic treatment (AB+ group) and 30 CDI-negative subjects not on antibiotic treatment (AB− group). The functional properties of the gut microbiomes of CDI-positive vs CDI-negative subjects were also assessed by shotgun metagenomics. A significantly lower microbial diversity was detected in CDI samples, whose microbiomes clustered separately from CDI-negative specimens. CDI was associated with a significant under-representation of gut commensals with putative protective functionalities, including Bacteroides, Alistipes, Lachnospira and Barnesiella, and over-representation of opportunistic pathogens. These findings were confirmed by functional shotgun metagenomics analyses, including an in-depth profiling of the Peptostreptococcaceae family. In CDI-negative patients, antibiotic treatment was associated with significant depletion of few commensals like Alistipes, but not with a reduction in species richness. A better understanding of the correlations between CDI and the microbiota in high-risk elderly subjects may contribute to identify therapeutic targets for CDI. PMID:27166072

  8. [Characterization of communities of heterotrophic bacteria associated with healthy and diseased corals in Nha Trang Bay (Vietnam)].

    Science.gov (United States)

    Beleneva, I A; Dautova, T I; Zhukova, N V

    2005-01-01

    A comparative investigation of the heterotrophic microflora of 11 species of healthy corals and of white-band-diseased and yellow-band-diseased corals inhabiting the reefs of Nha Trang Bay (Vietnam), which has been exposed to anthropogenic impact, was performed. Fifty-nine strains of heterotrophic bacteria isolated on Y/K and Endo media were investigated and characterized. All the isolates were identified at the genus level by consideration of the results of analysis of their phenotypic properties, determination of the molar percent of G+C bases in their DNA, and the composition of fatty acids of their lipids. In the composition of the microflora of tissues of healthy corals, gamma-proteobacteria prevailed, with halomonads being dominant among them. In addition, the gram-negative bacteria included Pseudomonas and Vibrio spp., members of the Cytophaga-Flavobacterium-Bacteroides (CFB) phylogenetic cluster, and Moraxella sp. The gram-positive bacteria revealed included Bacillus, Staphylococcus, Halococcus, and Micrococcus spp., and coryneform bacteria. In the composition of the microflora of the tissues of affected corals, bacteria of the family Enterobacteriaceae and of the genera Planococcus and Arthrobacter, which were not revealed in healthy hydrobionts, were found. The anthropogenic impact is not the sole factor determining the infection of corals. PMID:16315986

  9. Effect of radiation dose on the recovery of aerobic and anaerobic bacteria from mice

    International Nuclear Information System (INIS)

    The presence of aerobic and anaerobic bacteria in the blood, spleen, and liver was investigated in mice that were exposed to 7, 8, 9 or 10 Gy 60Co radiation. Microorganisms were detected more often in animals exposed to higher doses of radiation. The number of mice that were culture positive and the number of isolates in one site increased with increasing dose. Bacteria were recovered in mice killed at various times after radiation, in 3 of 100 mice exposed to 7 Gy, in 13 of 100 irradiated with 8 Gy, in 23 of 90 exposed to 9 Gy, and in 34 of 87 irradiated with 10 Gy. The predominant organisms recovered were Escherichia coli, anerobic Gram-positive cocci, Proteus mirabilis, Staphylococcus aureus, and Bacteroides spp. Escherichia coli and anaerobes were more often isolated in animals exposed to 10 Gy, while S. aureus was more often recovered in those irradiated with 9 Gy. These data demonstrate a relationship between the dose of radiation and the rate of infection due to enteric aerobic and anaerobic bacteria

  10. Role of anaerobes in acute pelvic inflammatory disease

    Directory of Open Access Journals (Sweden)

    Saini S

    2003-01-01

    Full Text Available Pouch of Douglas aspirates were collected from 50 women with history and examination suggestive of acute pelvic inflammatory disease (PID and 20 healthy women admitted for tubal ligation served as control. A total of 57 microorganisms were isolated from 37 patients out of 50 in study group. Of 37 positive cultures 21(56.7% were monomicrobial and 16(43.2% were polymicrobial. Most common symptom in study group was lower abdominal pain (90%, vaginal discharge (70% and irregular bleeding (40% and 30% patients had history of intrauterine contraceptive device (IUCD implantation. The predominant aerobic isolates were Escherichia coli, Coagulase Negative Staphylococcus (CONS, Staphylococcus aureus, Klebsiella pneumoniae while common anaerobes were Bacteroides fragilis, Prevotella melaninogenica, Fusobacterium nucleatum and Peptostreptococcus spp. Our study shows that cefotaxime, cefuroxime and gentamicin may be used for gram negative aerobic bacilli; cloxacillin, cephaloridine and erythromycin for aerobic gram positive cocci and amikacin and ceftazidime for Pseudomonas aeruginosa. Thus for optimum therapy of acute PID it is beneficial to keep in mind major conceptual changes and therapeutic realities that have influenced current understanding of acute PID and have affected the choice of therapy.

  11. Role of anaerobes in acute pelvic inflammatory disease.

    Science.gov (United States)

    Saini, S; Gupta, N; Batra, G; Arora, D R

    2003-01-01

    Pouch of Douglas aspirates were collected from 50 women with history and examination suggestive of acute pelvic inflammatory disease (PID) and 20 healthy women admitted for tubal ligation served as control. A total of 57 microorganisms were isolated from 37 patients out of 50 in study group. Of 37 positive cultures 21(56.7%) were monomicrobial and 16(43.2%) were polymicrobial. Most common symptom in study group was lower abdominal pain (90%), vaginal discharge (70%) and irregular bleeding (40%) and 30% patients had history of intrauterine contraceptive device (IUCD) implantation. The predominant aerobic isolates were Escherichia coli, Coagulase Negative Staphylococcus (CONS), Staphylococcus aureus, Klebsiella pneumoniae while common anaerobes were Bacteroides fragilis, Prevotella melaninogenica, Fusobacterium nucleatum and Peptostreptococcus spp. Our study shows that cefotaxime, cefuroxime and gentamicin may be used for gram negative aerobic bacilli; cloxacillin, cephaloridine and erythromycin for aerobic gram positive cocci and amikacin and ceftazidime for Pseudomonas aeruginosa. Thus for optimum therapy of acute PID it is beneficial to keep in mind major conceptual changes and therapeutic realities that have influenced current understanding of acute PID and have affected the choice of therapy. PMID:17643017

  12. Kiwifruit (Actinidia deliciosa) changes intestinal microbial profile

    Science.gov (United States)

    Lee, Yuan Kun; Low, Kay Yi; Siah, Kewin; Drummond, Lynley M.; Gwee, Kok-Ann

    2012-01-01

    Background Kiwifruit is high in pectic polysaccharides and dietary fiber. This study aimed to find out how the ingestion of kiwifruit will affect intestinal microbiota populations, namely Lactobacillus, Bacteroides, Clostridium, Bifidobacterium, and Enterococcus. Methods Freeze dried kiwifruit (equivalent of two fresh kiwifruits) was given to each of the six subjects daily for four days. Faecal samples were collected before, during and after kiwifruit consumption. The faecal bacteria were enumerated by qPCR and RT qPCR methods. Results The effect of the kiwifruit on intestinal microbiota profile varied between individuals; in general, the kiwifruit demonstrated a prebiotic effect of promoting the content of faecal lactobacilli and bifidobacteria (as compared to the baselines of the same individual before consumption) for as long as the fruit was consumed. The effect was however transient, the levels of the two bacteria returned near to that of the baselines upon cessation of consumption. Conclusion Kiwifruit is a prebiotic in selectively enhancing the growth of intestinal lactic acid bacteria. PMID:23990838

  13. Kiwifruit (Actinidia deliciosa changes intestinal microbial profile

    Directory of Open Access Journals (Sweden)

    Yuan Kun Lee

    2012-06-01

    Full Text Available Background: Kiwifruit is high in pectic polysaccharides and dietary fiber. This study aimed to find out how the ingestion of kiwifruit will affect intestinal microbiota populations, namely Lactobacillus, Bacteroides, Clostridium, Bifidobacterium, and Enterococcus. Methods: Freeze dried kiwifruit (equivalent of two fresh kiwifruits was given to each of the six subjects daily for four days. Faecal samples were collected before, during and after kiwifruit consumption. The faecal bacteria were enumerated by qPCR and RT qPCR methods. Results: The effect of the kiwifruit on intestinal microbiota profile varied between individuals; in general, the kiwifruit demonstrated a prebiotic effect of promoting the content of faecal lactobacilli and bifidobacteria (as compared to the baselines of the same individual before consumption for as long as the fruit was consumed. The effect was however transient, the levels of the two bacteria returned near to that of the baselines upon cessation of consumption. Conclusion: Kiwifruit is a prebiotic in selectively enhancing the growth of intestinal lactic acid bacteria.

  14. Phylogenetic analysis and taxonomic study of marine Cytophaga-like bacteria: proposal for Tenacibaculum gen. nov. with Tenacibaculum maritimum comb. nov. and Tenacibaculum ovolyticum comb. nov., and description of Tenacibaculum mesophilum sp. nov. and Tenacibaculum amylolyticum sp. nov.

    Science.gov (United States)

    Suzuki, M; Nakagawa, Y; Harayama, S; Yamamoto, S

    2001-09-01

    Bacterial strains were isolated from sponge and green algae which were collected on the coast of Japan and Palau. The phylogenetic relationships of these isolates among marine species of the Cytophaga-Flavobacterium-Bacteroides complex were analysed by using their gyrB nucleotide sequences and translated peptide sequences (GyrB) in addition to 16S rDNA sequences. These isolates were closely related to the previously characterized marine Flexibacter species, [Flexibacter] maritimus and [Flexibacter] ovolyticus. These Flexibacter species are distantly related to Flexibacter flexilis, the type species of the genus Flexibacter, and phylogenetically belong to the family Flavobacteriaceae (according to analysis using both 16S rDNA and GyrB sequences). Their phylogenetic, chemotaxonomic and phenotypic characteristics prompted the proposal that these two species should be transferred to the new genus Tenacibaculum, as Tenacibaculum maritimum and Tenacibaculum ovolyticum, respectively. Two additional new species of the genus Tenacibaculum, Tenacibaculum mesophilum gen. nov., sp. nov. (= MBIC 1140T = IFO 16307T) and Tenacibaculum amylolyticum gen. nov., sp. nov. (= MBIC 4355T = IFO 16310T), which were isolated from sponges and macroalgae, are also reported. For taxonomic considerations at the species level, the resolution of gyrB sequences was superior to that of 16S rDNA sequences, and the grouping based on the gyrB phylogram was consistent with DNA-DNA hybridization results. PMID:11594591

  15. Using microbiological tracers to assess the impact of winter land use restrictions on the quality of stream headwaters in a small catchment.

    Science.gov (United States)

    Flynn, Raymond M; Deakin, Jenny; Archbold, Marie; Cushnan, Hugh; Kilroy, Kate; O'Flaherty, Vincent; Misstear, Bruce D

    2016-01-15

    Diverse land use activities can elevate risk of microbiological contamination entering stream headwaters. Spatially distributed water quality monitoring carried out across a 17 km(2) agricultural catchment aimed to characterize microbiological contamination reaching surface water and investigate whether winter agricultural land use restrictions proved effective in addressing water quality degradation. Combined flow and concentration data revealed no significant difference in fecal indicator organism (FIO) fluxes in base flow samples collected during the open and prohibited periods for spreading organic fertilizer, while relative concentrations of Escherichia coli, fecal streptococci and sulfite reducing bacteria indicated consistently fresh fecal pollution reached aquatic receptors during both periods. Microbial source tracking, employing Bacteroides 16S rRNA gene markers, demonstrated a dominance of bovine fecal waste in river water samples upstream of a wastewater treatment plant discharge during open periods. This contrasted with responses during prohibited periods where human-derived signatures dominated. Differences in microbiological signature, when viewed with hydrological data, suggested that increasing groundwater levels restricted vertical infiltration of effluent from on-site wastewater treatment systems and diverted it to drains and surface water. Study results reflect seasonality of contaminant inputs, while suggesting winter land use restrictions can be effective in limiting impacts of agricultural wastes to base flow water quality. PMID:26470010

  16. Growth conditions determine the DNF2 requirement for symbiosis.

    Directory of Open Access Journals (Sweden)

    Fathi Berrabah

    Full Text Available Rhizobia and legumes are able to interact in a symbiotic way leading to the development of root nodules. Within nodules, rhizobia fix nitrogen for the benefit of the plant. These interactions are efficient because spectacularly high densities of nitrogen fixing rhizobia are maintained in the plant cells. DNF2, a Medicago truncatula gene has been described as required for nitrogen fixation, bacteroid's persistence and to prevent defense-like reactions in the nodules. This manuscript shows that a Rhizobium mutant unable to differentiate is not sufficient to trigger defense-like reactions in this organ. Furthermore, we show that the requirement of DNF2 for effective symbiosis can be overcome by permissive growth conditions. The dnf2 knockout mutants grown in vitro on agarose or Phytagel as gelling agents are able to produce nodules fixing nitrogen with the same efficiency as the wild-type. However, when agarose medium is supplemented with the plant defense elicitor ulvan, the dnf2 mutant recovers the fix- phenotype. Together, our data show that plant growth conditions impact the gene requirement for symbiotic nitrogen fixation and suggest that they influence the symbiotic suppression of defense reactions in nodules.

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

    Directory of Open Access Journals (Sweden)

    Kobayashi S.

    2009-06-01

    Full Text Available 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 electrophoretic mobility, of E. muris had almost the same mobility as that observed with the malic isoenzyme electrophorectic band of E. coli (UZG-EC-01 strain isolated from a gorilla. We determined the small subunit rRNA (SSU-rRNA gene sequence of the MG-EM-01 strain, and this sequence was observed to show 82.7% homology with that of the UZG-EC-01 strain. Further, the resultant phylogenetic tree for molecular taxonomy based on the SSU-rRNA genes of the 21 strains of the intestinal parasitic amoeba species indicated that the MG-EM-01 strain was most closely related to E. coli.

  18. Characterization of the microbial community in a lotic environment to assess the effect of pollution on nitrifying and potentially pathogenic bacteria.

    Science.gov (United States)

    Medeiros, J D; Araújo, L X; da Silva, V L; Diniz, C G; Cesar, D E; Del'Duca, A; Coelho, C M

    2014-08-01

    This study aimed to investigate microbes involved in the nitrogen cycle and potentially pathogenic bacteria from urban and rural sites of the São Pedro stream. Water samples were collected from two sites. A seasonal survey of bacterial abundance was conducted. The dissolved nutrient content was analysed. PCR and FISH analysis were performed to identify and quantify microbes involved in the nitrogen cycle and potentially pathogenic bacteria. The seasonal survey revealed that the bacterial abundance was similar along the year on the rural area but varied on the urban site. Higher concentration of dissolved nutrients in the urban area indicated a eutrophic system. Considering the nitrifying microbes, the genus Nitrobacter was found, especially in the urban area, and may act as the principal bacteria in converting nitrite into nitrate at this site. The molecular markers napA, amoA, and nfrA were more accumulated at the urban site, justifying the higher content of nutrients metabolised by these enzymes. Finally, high intensity of amplicons from Enterococcus, Streptococcus, Bacteroides/Prevotella/Porphyromonas, Salmonella, S. aureus, P. aeruginosa and the diarrheagenic lineages of E. coli were observed at the urban site. These results indicate a change in the structure of the microbial community imposed by anthrophic actions. The incidence of pathogenic bacteria in aquatic environments is of particular importance to public health, emphasising the need for sewage treatment to minimise the environmental impacts associated with urbanisation. PMID:25296210

  19. Photoinactivation of Eight Health-Relevant Bacterial Species: Determining the Importance of the Exogenous Indirect Mechanism.

    Science.gov (United States)

    Maraccini, Peter A; Wenk, Jannis; Boehm, Alexandria B

    2016-05-17

    It is presently unknown to what extent the endogenous direct, endogenous indirect, and exogenous indirect mechanisms contribute to bacterial photoinactivation in natural surface waters. In this study, we investigated the importance of the exogenous indirect mechanism by conducting photoinactivation experiments with eight health-relevant bacterial species (Bacteroides thetaiotaomicron, Campylobacter jejuni, Enterococcus faecalis, Escherichia coli K12, E. coli O157:H7, Salmonella enterica serovar Typhimurium LT2, Staphylococcus aureus, and Streptococcus bovis). We used three synthetic photosensitizers (methylene blue, rose bengal, and nitrite) and two model natural photosensitizers (Suwannee River natural organic matter and dissolved organic matter isolated from a wastewater treatment wetland) that generated singlet oxygen and hydroxyl radical. B. thetaiotaomicron had larger first order rate constants than all other organisms under all conditions tested. The presence of the synthetic photosensitizers generally enhanced photoinactivation of Gram-positive facultative anaerobes (Ent. faecalis, Staph. aureus, and Strep. bovis). Among Gram-negative bacteria, only methylene blue with E. coli K12 and rose bengal with C. jejuni showed an enhancing effect. The presence of model natural photosensitizers either reduced or did not affect photoinactivation rate constants. Our findings highlight the importance of the cellular membrane and photosensitizer properties in modulating the contribution of the exogenous indirect mechanism to the overall bacterial photoinactivation. PMID:27121126

  20. Identification of household bacterial community and analysis of species shared with human microbiome.

    Science.gov (United States)

    Jeon, Yoon-Seong; Chun, Jongsik; Kim, Bong-Soo

    2013-11-01

    Microbial populations in indoor environments, where we live and eat, are important for public health. Various bacterial species reside in the kitchen, and refrigerators, the major means of food storage within kitchens, can be a direct source of food borne illness. Therefore, the monitoring of microbiota in the refrigerator is important for food safety. We investigated and compared bacterial communities that reside in the vegetable compartment of the refrigerator and on the seat of the toilet, which is recognized as highly colonized by microorganisms, in ten houses using high-throughput sequencing. Proteobacteria, Firmicutes, Actinobacteria, and Bacteroidetes were predominant in refrigerator and toilet samples. However, Proteobacteria was more abundant in the refrigerator, and Firmicutes was more abundant in the toilet. These household bacterial communities were compared with those of human skin and gut to identify potential sources of household bacteria. Bacterial communities from refrigerators and toilets shared more species in common with human skin than gut. Opportunistic pathogens, including Propionibacterium acnes, Bacteroides vulgatus, and Staphylococcus epidermidis, were identified as species shared with human skin and gut microbiota. This approach can provide a general background of the household microbiota and a potential method of source-tracking for public health purposes. PMID:23743600

  1. Xylitol Affects the Intestinal Microbiota and Metabolism of Daidzein in Adult Male Mice

    Directory of Open Access Journals (Sweden)

    Motoi Tamura

    2013-12-01

    Full Text Available This study examined the effects of xylitol on mouse intestinal microbiota and urinary isoflavonoids. Xylitol is classified as a sugar alcohol and used as a food additive. The intestinal microbiota seems to play an important role in isoflavone metabolism. Xylitol feeding appears to affect the gut microbiota. We hypothesized that dietary xylitol changes intestinal microbiota and, therefore, the metabolism of isoflavonoids in mice. Male mice were randomly divided into two groups: those fed a 0.05% daidzein with 5% xylitol diet (XD group and those fed a 0.05% daidzein-containing control diet (CD group for 28 days. Plasma total cholesterol concentrations were significantly lower in the XD group than in the CD group (p < 0.05. Urinary amounts of equol were significantly higher in the XD group than in the CD group (p < 0.05. The fecal lipid contents (% dry weight were significantly greater in the XD group than in the CD group (p < 0.01. The cecal microbiota differed between the two dietary groups. The occupation ratios of Bacteroides were significantly greater in the CD than in the XD group (p < 0.05. This study suggests that xylitol has the potential to affect the metabolism of daidzein by altering the metabolic activity of the intestinal microbiota and/or gut environment. Given that equol affects bone health, dietary xylitol plus isoflavonoids may exert a favorable effect on bone health.

  2. Clinical and microbiological effects of a subantimicrobial dose of oral doxycycline on periodontitis in dogs.

    Science.gov (United States)

    Kim, S E; Hwang, S Y; Jeong, M; Lee, Y; Lee, E R; Park, Y W; Ahn, J S; Kim, S; Seo, K

    2016-02-01

    Doxycycline is regarded as an effective treatment for periodontal inflammation. In humans, it has been shown that the long-term administration of a subantimicrobial dose of doxycycline (SDD) does not induce antimicrobial effects on the subgingival microflora and furthermore does not affect antimicrobial susceptibility. The present study was designed to evaluate the influence of oral administration of SDD on normal periodontal microflora and antimicrobial susceptibility in dogs. Experimental periodontitis was induced in 12 experimental dogs using a silk and wire-twisted ligature for 60 days. After the periodontitis induction period, the ligature was removed, and dental cleaning (subgingival and supragingival ultrasonic scaling) was performed. The dogs were randomly assigned to one of two groups: an SDD group with six dogs receiving 2 mg/kg PO once daily and a control group with six dogs receiving a placebo. At weeks 0, 4 and 8, clinical periodontal parameters were evaluated. After the clinical assessments, subgingival plaque was sampled and then cultured in an anaerobic system for one week, and the total anaerobes, Porphyromonas spp., Bacteroides spp. and Pasteurella spp. counts were investigated. Using the agar dilution method, the minimum bactericidal concentration of doxycycline was evaluated and the resistance for doxycycline was monitored during this experimental phase. The clinical periodontal status of the SDD group was significantly improved compared to the control group (P  0.05), and antibacterial resistance was not established in the SDD group during the experimental periods (P dogs. PMID:26639830

  3. Probiotics and Acute Pancreatitis: There Is Still a Long Way to Go!

    Directory of Open Access Journals (Sweden)

    Generoso Uomo

    2016-05-01

    Full Text Available Probiotics are defined as “mono- or mixed cultures of live micro-organisms able to beneficially affect the host by improving the properties of the indigenous flora” [1]. The indigenous intestinal microflora is a complex ecosystem which develops early in life. In adulthood, this system consists of at least 500 different bacterial species with a maximum concentration of the bacteria in the ileum and colon [2]. More than 99% of the microorganisms in the colon are strictly anaerobic, such as bifidobacteria, peptostreptococci, Bacteroides spp., and Clostridium spp. [3]. Intestinal microflora has several important functions for the host including the production of vitamins, degradation of bile acids, digestion of nutrients and the conversion of (procarcinogenic substances. In addition, the colonization of the intestine by commensal bacteria is also important for the development and functioning of the immune system [4]. The functions of the intestinal microflora may be positively influenced by probiotics which exert a therapeutic effect through modification of the composition of indigenous intestinal microflora and its metabolic activity, prevention of overgrowth and colonization of pathogens, and stimulation of the immune system.

  4. Comparative Analysis of Glycoside Hydrolases Activities from Phylogenetically Diverse Marine Bacteria of the Genus Arenibacter

    Directory of Open Access Journals (Sweden)

    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.

  5. Microbiological profiles of sputum and gastric juice aspirates in Cystic Fibrosis patients.

    Science.gov (United States)

    Al-Momani, H; Perry, A; Stewart, C J; Jones, R; Krishnan, A; Robertson, A G; Bourke, S; Doe, S; Cummings, S P; Anderson, A; Forrest, T; Griffin, S M; Brodlie, M; Pearson, J; Ward, C

    2016-01-01

    Gastro-Oesophageal Reflux (GOR) is a key problem in Cystic Fibrosis (CF), but the relationship between lung and gastric microbiomes is not well understood. We hypothesised that CF gastric and lung microbiomes are related. Gastric and sputum cultures were obtained from fifteen CF patients receiving percutaneous endoscopic gastrostomy feeding. Non-CF gastric juice data was obtained through endoscopy from 14 patients without lung disease. Bacterial and fungal isolates were identified by culture. Molecular bacterial profiling used next generation sequencing (NGS) of the 16S rRNA gene. Cultures grew bacteria and/or fungi in all CF gastric juice and sputa and in 9/14 non-CF gastric juices. Pseudomonas aeruginosa(Pa) was present in CF sputum in 11 patients, 4 had identical Pa strains in the stomach. NGS data from non-CF gastric juice samples were significantly more diverse compared to CF samples. NGS showed CF gastric juice had markedly lower abundance of normal gut bacteria; Bacteroides and Faecalibacterium, but increased Pseudomonas compared with non-CF. Multivariate partial least squares discriminant analysis demonstrated similar bacterial profiles of CF sputum and gastric juice samples, which were distinct from non-CF gastric juice. We provide novel evidence suggesting the existence of an aerodigestive microbiome in CF, which may have clinical relevance. PMID:27245316

  6. Isolation of novel psychrophilic bacteria from Arctic sea ice

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    The phylogenetic diversity of culturable psychrophilic bacteria associated with sea ice from the high latitude regions of Canadian Basin and Chukchi Sea, Arctic, was investigated. A total of 34 psychropilic strains were isolated using three methods of (Ⅰ) dilution plating (at 4 ℃), (Ⅱ) bath culturing (at -1 ℃) and dilution plating, and (Ⅲ) cold shock (-20 ℃ for 24 h), bath culturing and dilution plating under aerobic conditions. Sea-ice samples were exposed to -20 ℃ for 24 h that might reduce the number of common microorganisms and encourage outgrowth of psychrophilic strains. This process might be able to be introduced to isolation psychrophilic bacteria from other environmental samples in future study. 16S rDNA nearly full-length sequence analysis revealed that psychrophilic strains felled in two phylogenetic divisions, γ-proteobacteria (in the genera Colwellia、Marinobacter、Shewanella、Glaciecola、Marinomonas and Pseudoalteromonas) and Cytophaga-Flexibacter-Bacteroides (Flavobacterium and Psychroflexus). Fifteen of bacterial isolates quite likely represented novel species (16S rDNA sequence similarity below 98%). One of strains (BSi20002) from Canadian Basin showed 100% sequence similarity to that of Marinobacter sp. ANT8277 isolated from the Antarctic Weddell sea ice, suggesting bacteria may have a bipolar distribution at the species level.

  7. Pyrosequencing Reveals a Core Community of Anodic Bacterial Biofilms in Bioelectrochemical Systems from China.

    Science.gov (United States)

    Xiao, Yong; Zheng, Yue; Wu, Song; Zhang, En-Hua; Chen, Zheng; Liang, Peng; Huang, Xia; Yang, Zhao-Hui; Ng, I-Son; Chen, Bor-Yann; Zhao, Feng

    2015-01-01

    Bioelectrochemical systems (BESs) are promising technologies for energy and product recovery coupled with wastewater treatment, and the core microbial community in electrochemically active biofilm in BESs remains controversy. In the present study, 7 anodic communities from 6 bioelectrochemical systems in 4 labs in southeast, north and south-central of China are explored by 454 pyrosequencing. A total of 251,225 effective sequences are obtained for 7 electrochemically active biofilm samples at 3% cutoff level. While Alpha-, Beta-, and Gamma-proteobacteria are the most abundant classes (averaging 16.0-17.7%), Bacteroidia and Clostridia are the two sub-dominant and commonly shared classes. Six commonly shared genera i.e., Azospira, Azospirillum, Acinetobacter, Bacteroides, Geobacter, Pseudomonas, and Rhodopseudomonas dominate the electrochemically active communities and are defined as core genera. A total of 25 OTUs with average relative abundance >0.5% were selected and designated as core OTUs, and some species relating to these OTUs have been reported electrochemically active. Furthermore, cyclic voltammetry and chronoamperometry tests show that two strains from Acinetobacter guillouiae and Stappia indica, bacteria relate to two core OTUs, are electrochemically active. Using randomly selected bioelectrochemical systems, the study has presented extremely diverse bacterial communities in anodic biofilms, though, we still can suggest some potentially microbes for investigating the electrochemical mechanisms in bioelectrochemical systems. PMID:26733958

  8. Semi-automatic in silico gap closure enabled de novo assembly of two Dehalobacter genomes from metagenomic data.

    Science.gov (United States)

    Tang, Shuiquan; Gong, Yunchen; Edwards, Elizabeth A

    2012-01-01

    Typically, the assembly and closure of a complete bacterial genome requires substantial additional effort spent in a wet lab for gap resolution and genome polishing. Assembly is further confounded by subspecies polymorphism when starting from metagenome sequence data. In this paper, we describe an in silico gap-resolution strategy that can substantially improve assembly. This strategy resolves assembly gaps in scaffolds using pre-assembled contigs, followed by verification with read mapping. It is capable of resolving assembly gaps caused by repetitive elements and subspecies polymorphisms. Using this strategy, we realized the de novo assembly of the first two Dehalobacter genomes from the metagenomes of two anaerobic mixed microbial cultures capable of reductive dechlorination of chlorinated ethanes and chloroform. Only four additional PCR reactions were required even though the initial assembly with Newbler v. 2.5 produced 101 contigs within 9 scaffolds belonging to two Dehalobacter strains. By applying this strategy to the re-assembly of a recently published genome of Bacteroides, we demonstrate its potential utility for other sequencing projects, both metagenomic and genomic. PMID:23284863

  9. Enteric short-chain fatty acids: microbial messengers of metabolism, mitochondria, and mind: implications in autism spectrum disorders

    Directory of Open Access Journals (Sweden)

    Derrick F. MacFabe

    2015-05-01

    Full Text Available Clinical observations suggest that gut and dietary factors transiently worsen and, in some cases, appear to improve behavioral symptoms in a subset of persons with autism spectrum disorders (ASDs, but the reason for this is unclear. Emerging evidence suggests ASDs are a family of systemic disorders of altered immunity, metabolism, and gene expression. Pre- or perinatal infection, hospitalization, or early antibiotic exposure, which may alter gut microbiota, have been suggested as potential risk factors for ASD. Can a common environmental agent link these disparate findings? This review outlines basic science and clinical evidence that enteric short-chain fatty acids (SCFAs, present in diet and also produced by opportunistic gut bacteria following fermentation of dietary carbohydrates, may be environmental triggers in ASD. Of note, propionic acid, a major SCFA produced by ASD-associated gastrointestinal bacteria (clostridia, bacteroides, desulfovibrio and also a common food preservative, can produce reversible behavioral, electrographic, neuroinflammatory, metabolic, and epigenetic changes closely resembling those found in ASD when administered to rodents. Major effects of these SCFAs may be through the alteration of mitochondrial function via the citric acid cycle and carnitine metabolism, or the epigenetic modulation of ASD-associated genes, which may be useful clinical biomarkers. It discusses the hypothesis that ASDs are produced by pre- or post-natal alterations in intestinal microbiota in sensitive sub-populations, which may have major implications in ASD cause, diagnosis, prevention, and treatment.

  10. Impact of a High-Fat or High-Fiber Diet on Intestinal Microbiota and Metabolic Markers in a Pig Model

    Directory of Open Access Journals (Sweden)

    Sonja N. Heinritz

    2016-05-01

    Full Text Available To further elaborate interactions between nutrition, gut microbiota and host health, an animal model to simulate changes in microbial composition and activity due to dietary changes similar to those in humans is needed. Therefore, the impact of two different diets on cecal and colonic microbial gene copies and metabolic activity, organ development and biochemical parameters in blood serum was investigated using a pig model. Four pigs were either fed a low-fat/high-fiber (LF, or a high-fat/low-fiber (HF diet for seven weeks, with both diets being isocaloric. A hypotrophic effect of the HF diet on digestive organs could be observed compared to the LF diet (p < 0.05. Higher gene copy numbers of Bacteroides (p < 0.05 and Enterobacteriaceae (p < 0.001 were present in intestinal contents of HF pigs, bifidobacteria were more abundant in LF pigs (p < 0.05. Concentrations of acetate and butyrate were higher in LF pigs (p < 0.05. Glucose was higher in HF pigs, while glutamic pyruvic transaminase (GPT showed higher concentrations upon feeding the LF diet (p < 0.001. However, C-reactive protein (CRP decreased with time in LF pigs (p < 0.05. In part, these findings correspond to those in humans, and are in support of the concept of using the pig as human model.

  11. Relationship of human-associated microbial source tracking markers with Enterococci in Gulf of Mexico waters.

    Science.gov (United States)

    Gordon, Katrina V; Brownell, Miriam; Wang, Shiao Y; Lepo, Joe Eugene; Mott, Joanna; Nathaniel, Rajkumar; Kilgen, Marilyn; Hellein, Kristen N; Kennedy, Elizabeth; Harwood, Valerie J

    2013-03-01

    Human and ecosystem health can be damaged by fecal contamination of recreational waters. Microbial source tracking (MST) can be used to specifically detect domestic sewage containing human waste, thereby informing both risk assessment and remediation strategies. Previously, an inter-laboratory collaboration developed standardized PCR methods for a bacterial, an archaeal, and a viral indicator of human sewage. Here we present results for two subsequent years of field testing in fresh and salt water by five laboratories across the U.S. Gulf Coast (two in Florida and one each in Mississippi, Louisiana and Texas) using common standard operating procedures (SOPs) developed previously. Culturable enterococci were enumerated by membrane filtration, and PCR was used to detect three MST markers targeting domestic sewage: human-associated Bacteroides (HF183), Methanobrevibacter smithii and human polyomaviruses BK and JC (HPyVs). Detection of sewage markers in surface waters was significantly associated with higher enterococci levels and with exceedance of the recreational water quality standard in four or three regions, respectively. Sewage markers were frequently co-detected in single samples, e.g., M. smithii and HF183 were co-detected in 81% of Louisiana samples, and HPyVs and M. smithii were co-detected in over 40% of southwest Florida and Mississippi samples. This study demonstrates the robustness and inter-laboratory transferability of these three markers for the detection of pollution from domestic sewage in the waters impacting the Gulf of Mexico over a coastal range of over 1000 miles. PMID:23260177

  12. Fecal bacterial microbiome diversity in chronic HIV-infected patients in China

    Science.gov (United States)

    Sun, Yang; Ma, Yingfei; Lin, Ping; Tang, Yi-Wei; Yang, Liying; Shen, Yinzhong; Zhang, Renfan; Liu, Li; Cheng, Jun; Shao, Jiashen; Qi, Tangkai; Tang, Yan; Cai, Rentian; Guan, Liqian; Luo, Bin; Sun, Meiyan; Li, Ben; Pei, Zhiheng; Lu, Hongzhou

    2016-01-01

    The purpose of this study was to identify fecal bacterial microbiome changes in patients with chronic human immunodeficiency virus (HIV) infection in China. Bacterial 16S rRNA genes were amplified, sequenced (454 pyrosequencing), and clustered into operational taxonomic units using the QIIME software. Relative abundance at the phylum and genus levels were calculated. Alpha diversity was determined by Chao 1 and observed-species indices, and beta diversity was determined by double principal component analysis using the estimated phylogeny-based unweighted Unifrac distance matrices. Fecal samples of the patients with chronic HIV-infection tended to be enriched with bacteria of the phyla Firmicutes (47.20%±0.43 relative abundance) and Proteobacteria (37.21%±0.36) compared with those of the non-HIV infected controls (17.95%±0.06 and 3.81%±0.02, respectively). Members of the genus Bilophila were exclusively detected in samples of the non-HIV infected controls. Bacteroides and arabacteroides were more abundant in the chronic HIV-infected patients. Our study indicated that chronic HIV-infected patients in China have a fecal bacterial microbiome composition that is largely different from that found in non-HIV infected controls, and further study is needed to evaluate whether microbiome changes play a role in disease complications in the distal gut, including opportunistic infections. PMID:27048741

  13. Correlation between diet and gut bacteria in a population of young adults.

    Science.gov (United States)

    Mayorga Reyes, Lino; González Vázquez, Raquel; Cruz Arroyo, Schahrasad M; Melendez Avalos, Araceli; Reyes Castillo, Pedro A; Chavaro Pérez, David A; Ramos Terrones, Idalia; Ramos Ibáñez, Norma; Rodríguez Magallanes, Magdalena M; Langella, Philippe; Bermúdez Humarán, Luis; Azaola Espinosa, Alejandro

    2016-06-01

    Dietary habits strongly influence gut microbiota. The aim of this study was to compare and correlated the abundance of Firmicutes and Bacteroidetes phyla, some representative bacteria of these phyla such as Bacteroides thetaiotaomicron, Prevotella, Faecalibacterium prausnitzii, Clostridium leptum and Bifidobacterium longum as a member of Actinobacteria phylum in young adults with their food intake. Faecal samples used came from lean subjects (BMI = 19.83 ± 0.94 kg/m(2)), overweight (BMI = 27.17 ± 0.51 kg/m(2)) and obese (BMI = 41.33 ± 5.25 kg/m(2)). There were significant differences in total studied gut microbiota between the overweight and lean groups. Members of the Firmicutes phylum, and Bifidobacterium longum, were more abundant in the lean group. The results suggest that diet rich in unsaturated fatty acids and fibre promote an abundant population of beneficial bacteria such as B. longum and Bacteroidetes. However, it has been considered that the results may be biased due to the size of the individuals studied; therefore the results could be only valid for the studied population. PMID:27018166

  14. Microbiological profiles of sputum and gastric juice aspirates in Cystic Fibrosis patients

    Science.gov (United States)

    Al-momani, H.; Perry, A.; Stewart, C. J.; Jones, R.; Krishnan, A.; Robertson, A. G.; Bourke, S.; Doe, S.; Cummings, S. P.; Anderson, A.; Forrest, T.; Griffin, S. M.; Brodlie, M.; Pearson, J.; Ward, C.

    2016-01-01

    Gastro-Oesophageal Reflux (GOR) is a key problem in Cystic Fibrosis (CF), but the relationship between lung and gastric microbiomes is not well understood. We hypothesised that CF gastric and lung microbiomes are related. Gastric and sputum cultures were obtained from fifteen CF patients receiving percutaneous endoscopic gastrostomy feeding. Non-CF gastric juice data was obtained through endoscopy from 14 patients without lung disease. Bacterial and fungal isolates were identified by culture. Molecular bacterial profiling used next generation sequencing (NGS) of the 16S rRNA gene. Cultures grew bacteria and/or fungi in all CF gastric juice and sputa and in 9/14 non-CF gastric juices. Pseudomonas aeruginosa(Pa) was present in CF sputum in 11 patients, 4 had identical Pa strains in the stomach. NGS data from non-CF gastric juice samples were significantly more diverse compared to CF samples. NGS showed CF gastric juice had markedly lower abundance of normal gut bacteria; Bacteroides and Faecalibacterium, but increased Pseudomonas compared with non-CF. Multivariate partial least squares discriminant analysis demonstrated similar bacterial profiles of CF sputum and gastric juice samples, which were distinct from non-CF gastric juice. We provide novel evidence suggesting the existence of an aerodigestive microbiome in CF, which may have clinical relevance. PMID:27245316

  15. Linking fecal bacteria in rivers to landscape, geochemical, and hydrologic factors and sources at the basin scale.

    Science.gov (United States)

    Verhougstraete, Marc P; Martin, Sherry L; Kendall, Anthony D; Hyndman, David W; Rose, Joan B

    2015-08-18

    Linking fecal indicator bacteria concentrations in large mixed-use watersheds back to diffuse human sources, such as septic systems, has met limited success. In this study, 64 rivers that drain 84% of Michigan's Lower Peninsula were sampled under baseflow conditions for Escherichia coli, Bacteroides thetaiotaomicron (a human source-tracking marker), landscape characteristics, and geochemical and hydrologic variables. E. coli and B. thetaiotaomicron were routinely detected in sampled rivers and an E. coli reference level was defined (1.4 log10 most probable number⋅100 mL(-1)). Using classification and regression tree analysis and demographic estimates of wastewater treatments per watershed, septic systems seem to be the primary driver of fecal bacteria levels. In particular, watersheds with more than 1,621 septic systems exhibited significantly higher concentrations of B. thetaiotaomicron. This information is vital for evaluating water quality and health implications, determining the impacts of septic systems on watersheds, and improving management decisions for locating, constructing, and maintaining on-site wastewater treatment systems. PMID:26240328

  16. [Strict anaerobic bacteria: comparative study of various beta-lactam antibiotics in combination with tazobactam or sulbactam].

    Science.gov (United States)

    Dubreuil, L; Sedallian, A

    1991-05-01

    The minimal inhibitory concentrations of piperacillin (PIP) or cefotaxime (CTX) alone or in combination with tazobactam (TAZ) were determined against 168 anaerobes. All the strains were inhibited by PIP + TAZ, but certain strains resistant to CTX + TAZ were found among B. fragilis, Eubacterium and Peptostreptococcus. The second investigations included 30 strains of Bacteroides fragilis. Concentrations of 2, 4 and 8 mg/l of TAZ and sulbactam (SUL) were combined with piperacillin or cefotaxime. The two beta-lactamase-inhibitors had similar activities when used at 2 or 4 mg/l, but at 8 mg/l TAZ was more active than SUL. All B. fragilis strains were inhibited by PIP + TAZ or PIP + SUL, whereas resistance was observed with CTX + SUL or CTX + TAZ. On the same strains the activities of 6 beta-lactams (PIP, mezlocillin, ticarcillin (TIC), CTX, ceftriaxone and ceftazidime) were determined in combination with either SUL 4 mg/l or TAZ 8 mg/l. Only PIP or TIC + SUL or TAZ were able to inhibit at least 90% of tested strains. No resistance could be detected with PIP + TAZ combination. As conclusion, the two inhibitors when combined with PIP or TIC offered greater activity against both Gram positive or negative anaerobes and PIP + TAZ remained the more potent combination. PMID:1652729

  17. Increased in vitro activity of ceftriaxone by addition of tazobactam against clinical isolates of anaerobes.

    Science.gov (United States)

    Aldridge, K E; Morice, N; Schiro, D D

    1994-08-01

    A total of 461 clinical strains of anaerobes were tested using a broth microdilution test to determine the activity of the combination of ceftriaxone and tazobactam and other antimicrobials against these isolates. Ceftriaxone was combined with tazobactam in ratios of 1:1, 2:1, 4:1, and 8:1 and twofold dilutions of ceftriaxone in constant concentrations to tazobactam of 2, 4, 8, 16, and 32 micrograms/ml. Against beta-lactamase-producing strains of the Bacteroides fragilis group, B. capillosus, and Prevotella species all combinations of ceftriaxone and tazobactam showed enhanced in vitro activity and were eight- to 2048-fold more active than ceftriaxone alone. By comparison ceftriaxone and tazobactam showed superior or equal activity to ampicillin and sulbactam, piperacillin and tazobactam, amoxicillin and clavulanate, ticarcillin and clavulanate, and metronidazole against these same strains. Against beta-lactamase nonproducing strains of Porphyromonas, Fusobacterium, Clostridium, Eubacterium, Peptostreptococcus, and Veillonella parvula the addition of tazobactam produced no appreciable enhanced ceftriaxone activity. Fixed concentrations of tazobactam at 2 and 4 micrograms/ml appear to be most suitable for susceptibility testing and are within the pharmacologic profile of this inhibitor. Pharmacologic and toxicity studies will be needed to define the role of ceftriaxone and tazobactam in infectious diseases. PMID:7851086

  18. 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.

  19. A microfluidics-based in vitro model of the gastrointestinal human-microbe interface.

    Science.gov (United States)

    Shah, Pranjul; Fritz, Joëlle V; Glaab, Enrico; Desai, Mahesh S; Greenhalgh, Kacy; Frachet, Audrey; Niegowska, Magdalena; Estes, Matthew; Jäger, Christian; Seguin-Devaux, Carole; Zenhausern, Frederic; Wilmes, Paul

    2016-01-01

    Changes in the human gastrointestinal microbiome are associated with several diseases. To infer causality, experiments in representative models are essential, but widely used animal models exhibit limitations. Here we present a modular, microfluidics-based model (HuMiX, human-microbial crosstalk), which allows co-culture of human and microbial cells under conditions representative of the gastrointestinal human-microbe interface. We demonstrate the ability of HuMiX to recapitulate in vivo transcriptional, metabolic and immunological responses in human intestinal epithelial cells following their co-culture with the commensal Lactobacillus rhamnosus GG (LGG) grown under anaerobic conditions. In addition, we show that the co-culture of human epithelial cells with the obligate anaerobe Bacteroides caccae and LGG results in a transcriptional response, which is distinct from that of a co-culture solely comprising LGG. HuMiX facilitates investigations of host-microbe molecular interactions and provides insights into a range of fundamental research questions linking the gastrointestinal microbiome to human health and disease. PMID:27168102

  20. Structural modulation of gut microbiota by chondroitin sulfate and its oligosaccharide.

    Science.gov (United States)

    Shang, Qingsen; Shi, Jingjing; Song, Guanrui; Zhang, Meifang; Cai, Chao; Hao, Jiejie; Li, Guoyun; Yu, Guangli

    2016-08-01

    Chondroitin sulfate (CS) as a dietary supplement and a symptomatic slow acting (SYSA) drug has been used for years. Recently, CS has been demonstrated to be readily degraded and fermented in vitro by specific human gut microbes, hinting that dietary CS may pose a potential effect on gut microbiota composition in vivo. However, until now, little information is available on modulations of gut microbiota by CS. In the present study, modulations of gut microbiota in Kunming mice by CS and its oligosaccharide (CSO) were investigated by high-throughput sequencing. As evidenced by Heatmap and principal component analysis (PCA), the female microbiota were more vulnerable than the male microbiota to CS and CSO treatment. Besides, it is of interest to found that CS and CSO had differing effects on the abundance of Bacteroidales S24-7, Bacteroides, Helicobacter, Odoribacter, Prevotellaceae and Lactobacillus in male mice versus female mice. Collectively, we demonstrated a sex-dependent effect on gut microbiota of CS and CSO. In addition, since gut microbiota exerts a major effect on host physiology, our study highlighted that certain beneficial effects of CS may be associated with modulations of gut microbiota, which merits further investigation. PMID:27164502