| [growth of non-sporing anaerobes in an oxygen-free blood culture system (author's transl)]. | the efficacy of the commercially available vacutainer blood culture system to support the growth of non-sporing anaerobes was compared with two laboratory-prepared blood culture media (supplemented thioglycollate medium and brain heart infusion). the media were inoculated with 10, 100 and 1000 organisms of the species tested, and the number of colony-forming units was determined at intervals of 8-10 hrs. analogous experiments were performed with batches of the media to which 10% vol/vol of human ... | 1977 | 325956 |
| evidence for natural transfer of a tetracycline resistance gene between bacteria from the human colon and bacteria from the bovine rumen. | previously, we demonstrated conjugal transfer of a specially constructed shuttle vector, prdb5, from the human colonic anaerobe bacteroides uniformis to the ruminal anaerobe prevotella (bacteroides) ruminicola b(1)4. we have now shown that naturally occurring gene transfer elements in bacteroides species and prevotella ruminicola can also be transferred between these two genera. a self-transmissible chromosomal element originally found in a clinical isolate of bacteroides fragilis (tcr emr 12256 ... | 1992 | 1599250 |
| development of a dna probe for streptococcus bovis by using a cloned amylase gene. | streptococcus bovis is a normal inhabitant of the rumen but has been implicated as a causative agent for ruminal lactic acidosis and related problems. while rarely isolated from humans, s. bovis has been identified as a causative agent for endocarditis, meningitis, and septicemia. recent reports have also suggested a correlation between human colonic carcinoma and increased levels of s. bovis. identification of s. bovis strains of human origin has been problematic because of variations in result ... | 1993 | 7691873 |
| [use of cell-surface antigens of bacteroides thetaiotaomicron in the passive hemagglutination test and in the inhibition of passive hemagglutination]. | the antigens were prepared from three b. thetaiotaomicron strains of different origin (nctc 10582--reference strain, 312/85--isolated from a pancreas fistula drain of a patient, and 9/18--derived from normal human intestinal microflora). lipopolysaccharides were extracted by the hot phenol-water method and purified by nuclease tretment. degradation of lipopolysaccharides was achieved by mild acid hydrolysis obtaining polysaccharide (ps) and lipid (la) fractions. capsular polysaccharide (cps) was ... | 1995 | 8833931 |
| development of a membrane-array method for the detection of human intestinal bacteria in fecal samples. | a membrane-array method was developed for the detection of human intestinal bacteria in fecal samples without using the expensive microarray-arrayer and laser-scanner. the 16s rdna sequences of 20 predominant human intestinal bacterial species were used to design oligonucleotide probes. three 40-mer oligonucleotides specific for each bacterial species (total 60 probes) were synthesized and applied to nitrocellulose membranes. digoxigenin (dig)-labeled 16s rdnas were amplified by polymerase chain ... | 2002 | 12477438 |
| human microbiota-secreted factors inhibit shiga toxin synthesis by enterohemorrhagic escherichia coli o157:h7. | escherichia coli o157:h7 is a food-borne pathogen causing hemorrhagic colitis and hemolytic-uremic syndrome, especially in children. the main virulence factor responsible for the more serious disease is the shiga toxin 2 (stx2), which is released in the gut after oral ingestion of the organism. although it is accepted that the amount of stx2 produced by e. coli o157:h7 in the gut is critical for the development of disease, the eukaryotic or prokaryotic gut factors that modulate stx2 synthesis ar ... | 2009 | 19064636 |
| integrated analysis of established and novel microbial and chemical methods for microbial source tracking. | several microbes and chemicals have been considered as potential tracers to identify fecal sources in the environment. however, to date, no one approach has been shown to accurately identify the origins of fecal pollution in aquatic environments. in this multilaboratory study, different microbial and chemical indicators were analyzed in order to distinguish human fecal sources from nonhuman fecal sources using wastewaters and slurries from diverse geographical areas within europe. twenty-six par ... | 2006 | 16957211 |
| structure and mechanism of a bacterial beta-glucosaminidase having o-glcnacase activity. | o-glcnac is an abundant post-translational modification of serine and threonine residues of nucleocytoplasmic proteins. this modification, found only within higher eukaryotes, is a dynamic modification that is often reciprocal to phosphorylation. in a manner analogous to phosphatases, a glycoside hydrolase termed o-glcnacase cleaves o-glcnac from modified proteins. enzymes with high sequence similarity to human o-glcnacase are also found in human pathogens and symbionts. we report the three-dime ... | 2006 | 16565725 |
| operon prediction without a training set. | motivation: annotation of operons in a bacterial genome is an important step in determining an organism's transcriptional regulatory program. while extensive studies of operon structure have been carried out in a few species such as escherichia coli, fewer resources exist to inform operon prediction in newly sequenced genomes. in particular, many extant operon finders require a large body of training examples to learn the properties of operons in the target organism. for newly sequenced genomes, ... | 2005 | 15539453 |
| formation of allyl isothiocyanate from sinigrin in the digestive tract of rats monoassociated with a human colonic strain of bacteroides thetaiotaomicron. | a human digestive strain of bacteroides thetaiotaomicron was tested for its ability to metabolise sinigrin, a glucosinolate commonly found in brassica vegetables. gnotobiotic rats harbouring the bacterial strain were orally dosed with 50 micromol sinigrin. hplc analysis of the digestive contents showed that sinigrin was degraded in the large bowel, where b. thetaiotaomicron was established at a high level. concurrently, a hydrolysis product of sinigrin, allyl isothiocyanate, was identified by gc ... | 2001 | 11287153 |
| molecular analysis of commensal host-microbial relationships in the intestine. | human beings contain complex societies of indigenous microbes, yet little is known about how resident bacteria shape our physiology. we colonized germ-free mice with bacteroides thetaiotaomicron, a prominent component of the normal mouse and human intestinal microflora. global intestinal transcriptional responses to colonization were observed with dna microarrays, and the cellular origins of selected responses were established by laser-capture microdissection. the results reveal that this commen ... | 2001 | 11157169 |
| evaluation of 16s rrna and cellular fatty acid profiles as markers of human intestinal bacterial growth in the chemostat. | chemostats were used to study the effects of carbon and nitrogen limitation and specific growth rate on 16s rrna synthesis and cellular fatty acid (cfa) profiles in four human intestinal bacteria (bacteroides thetaiotaomicron, bifidobacterium adolescentis, clostridium bifermentans and cl. difficile). cellular fatty acid synthesis varied with dilution rate and nutrient availability in different species, but these cellular constituents were relatively stable phenotypic characteristics in bact. the ... | 2000 | 11054172 |
| [toxins of bacteroides fragilis and bacteroides thetaiotaomicron rods as stimulators of adhesion molecule expression on the surface of vascular endothelial cells]. | lipopolysaccharides from four bacteroides fragilis strains: one nonenterotoxigenic (ntbf) and three enterotoxigenic (etbf), and from three b. thetaiotaomicron strains were extracted by hot phenol-water method and purified. b. fragilis enterotoxin was prepared according to the procedure of van tassell et al. (1992). the influence of the examined toxins on the expression of adhesion molecules: icam-1, vcam-1 and e-selectin on hmec-1 (human dermal microvascular endothelial cells) was assayed in eli ... | 1999 | 10865439 |
| utilization of algal polysaccharides by human colonic bacteria, in axenic culture or in association with hydrogenotrophic microorganisms. | the ability of different hydrolytic bacteria from the human colon to grow on various algal polymers (carrageenans, palmaria palmata xylan, ulvan, desulphated ulvan and laminaran) was investigated and the interactions between bacteroides thetaiotaomicron and h2-utilizing microorganisms (one methanogenic archaea and an acetogenic bacterium) were studied during laminaran degradation. none of the algal polysaccharides supported the growth of any of the hydrolytic species tested, except for laminaran ... | 1997 | 9178362 |
| characterization of a new type of bacteroides conjugative transposon, tcr emr 7853. | results of previous investigations suggested that the conjugative transposons found in human colonic bacteroides species were all members of a closely related family of elements, exemplified by tcr emr dot. we have now found a new type of conjugative transposon, tcr emr 7853, that does not belong to this family. tcr emr 7853 has approximately the same size as the tcr emr dot-type elements (70 to 80 kbp) and also carries genes encoding resistance to tetracycline (tcr) and erythromycin (emr); howe ... | 1994 | 7961412 |
| effect of long generation times on growth of bacteroides thetaiotaomicron in carbohydrate-induced continuous culture. | we investigated the ability of bacteroides thetaiotaomicron, an obligate anaerobe from human colonic microflora, to grow in a carbohydrate-limited continuous culture at generation times ranging from 3.5 to 28 h per division. four carbohydrates were tested: glucose, n-acetylglucosamine, glucuronic acid, and glucosamine. at a generation time of 3.5 h per division, the growth yields for bacteria growing on glucose, n-acetylglucosamine, and glucuronic acid were 76, 68, and 50 g of cells (dry weight) ... | 1981 | 7240086 |
| quantitative variability in requirements for opsonization of strains within the bacteroides fragilis group. | requirements for opsonization of various strains within the species bacteroides fragilis, bacteroides thetaiotaomicron, bacteroides vulgatus, and bacteroides distasonis were investigated. the minimal concentration of normal human serum that facilitated maximal uptake by human peripheral leukocytes of 14c-labeled strains ranged from 5% to 80%. heated (56 c at 30 min) serum produced less uptake than untreated serum, suggesting that complement was required for opsonization. using human serum deplet ... | 1983 | 6631060 |
| participation of immunoglobulin and the alternative complement pathway in opsonization of bacteroides fragilis and bacteroides thetaiotaomicron. | studies were conducted to determine the requirements for immunoglobulin and complement in opsonization of bacteroides fragilis and bacteroides thetaiotaomicron. the ability of human sera depleted of immunoglobulin or of components of complement to promote the phagocytosis and intracellular killing of the two strains of bacteroides by human leukocytes was measured in vitro under anaerobic conditions. neither hypogammaglobulinemic sera nor pooled normal human serum that was heated at 56 c for 30 ... | 1979 | 549187 |
| specificity of polysaccharide use in intestinal bacteroides species determines diet-induced microbiota alterations. | the intestinal microbiota impacts many facets of human health and is associated with human diseases. diet impacts microbiota composition, yet mechanisms that link dietary changes to microbiota alterations remain ill-defined. here we elucidate the basis of bacteroides proliferation in response to fructans, a class of fructose-based dietary polysaccharides. structural and genetic analysis disclosed a fructose-binding, hybrid two-component signaling sensor that controls the fructan utilization locu ... | 2010 | 20603004 |
| resistance trends of bacteroides fragilis group over an 8-year period, 1997-2004, in korea. | bacteroides fragilis group organisms are the most frequently isolated anaerobes in human infections. increasing resistance to various antimicrobial agents is a significant problem in choosing appropriate antimicrobial agents to treat anaerobic infections. periodic monitoring of the regional resistance trends of b. fragilis group isolates is needed. | 2009 | 19726890 |
| structural insight into the mechanism of streptozotocin inhibition of o-glcnacase. | despite decades of its use in diabetes research, the mechanism of cytotoxicity of streptozotocin (stz) toward pancreatic beta-islet cells has remained a topic of discussion. although stz toxicity is likely a function of its capacity to promote dna alkylation, it has been proposed that stz induces pancreatic beta-cell death through o-glcnacase inhibition. in this report, we explore the binding mode of stz to a close homolog of human o-glcnacase, btgh84 from bacteroides thetaiotaomicron. our resul ... | 2009 | 19217614 |
| structure of a susd homologue, bt1043, involved in mucin o-glycan utilization in a prominent human gut symbiont. | mammalian distal gut bacteria have an expanded capacity to utilize glycans. in the absence of dietary sources, some species rely on host-derived mucosal glycans. the ability of bacteroides thetaiotaomicron, a prominent human gut symbiont, to forage host glycans contributes to both its ability to persist within an individual host and its ability to be transmitted naturally to new hosts at birth. the molecular basis of host glycan recognition by this species is still unknown but likely occurs thro ... | 2009 | 19191477 |
| use of a bacteroides thetaiotaomicron-specific alpha-1-6, mannanase quantitative pcr to detect human faecal pollution in water. | the aims of this work were to develop a quantitative test, based on bacteroides thetaiotaomicron, for human faecal pollution in water and to evaluate test performance. | 2008 | 19149766 |
| the structural basis of substrate recognition in an exo-beta-d-glucosaminidase involved in chitosan hydrolysis. | family 2 of the glycoside hydrolase classification is one of the largest families. structurally characterized members of this family include enzymes with beta-galactosidase activity (escherichia coli lacz), beta-glucuronidase activity (homo sapiens gusb), and beta-mannosidase activity (bacteroides thetaiotaomicron btman2a). here, we describe the structure of a family 2 glycoside hydrolase, csxa, from amycolatopsis orientalis that has exo-beta-d-glucosaminidase (exo-chitosanase) activity. analysi ... | 2009 | 18976664 |
| effects of the gut microbiota on host adiposity are modulated by the short-chain fatty-acid binding g protein-coupled receptor, gpr41. | the distal human intestine harbors trillions of microbes that allow us to extract calories from otherwise indigestible dietary polysaccharides. the products of polysaccharide fermentation include short-chain fatty acids that are ligands for gpr41, a g protein-coupled receptor expressed by a subset of enteroendocrine cells in the gut epithelium. to examine the contribution of gpr41 to energy balance, we compared gpr41-/- and gpr41+/+ mice that were either conventionally-raised with a complete gut ... | 2008 | 18931303 |
| starch catabolism by a prominent human gut symbiont is directed by the recognition of amylose helices. | 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 bacteroi ... | 2008 | 18611383 |
| restored fitness leads to long-term persistence of resistant bacteroides strains in the human intestine. | acquired antibiotic resistance typically confers a cost to the bacteria, but these costs can be reduced by genetic compensation over time. the fitness of two bacteroides thetaiotaomicron clones consecutively isolated in vivo was studied using an in vitro pair-wise competition method. the isolates derived from faecal samples of two clindamycin-exposed healthy volunteers and the two b. thetaiotaomicron clone types could be followed up to 18 months in these two subjects. the two clones were origina ... | 2008 | 18434218 |
| plant carbohydrate scavenging through tonb-dependent receptors: a feature shared by phytopathogenic and aquatic bacteria. | tonb-dependent receptors (tbdrs) are outer membrane proteins mainly known for the active transport of iron siderophore complexes in gram-negative bacteria. analysis of the genome of the phytopathogenic bacterium xanthomonas campestris pv. campestris (xcc), predicts 72 tbdrs. such an overrepresentation is common in xanthomonas species but is limited to only a small number of bacteria. here, we show that one xcc tbdr transports sucrose with a very high affinity, suggesting that it might be a sucro ... | 2007 | 17311090 |
| bacteria and early human development. | our understanding of the relationship between microbes and their animal hosts have changed dramatically in the last decade. the development of powerful new molecular methods as well as different animal models, particularly germ free rodents, has enabled precise characterisation of the ways in which commensal bacteria in the gastrointestinal tract and other areas interact with their hosts. it is now clear that animal development, far from being genetically determined is intimately bound up with t ... | 2007 | 17289307 |
| mannose foraging by bacteroides thetaiotaomicron: structure and specificity of the beta-mannosidase, btman2a. | the human colonic bacterium bacteroides thetaiotaomicron, which plays an important role in maintaining human health, produces an extensive array of exo-acting glycoside hydrolases (gh), including 32 family gh2 glycoside hydrolases. although it is likely that these enzymes enable the organism to utilize dietary and host glycans as major nutrient sources, the biochemical properties of these gh2 glycoside hydrolases are currently unclear. here we report the biochemical properties and crystal struct ... | 2007 | 17287210 |
| functional genomic and metabolic studies of the adaptations of a prominent adult human gut symbiont, bacteroides thetaiotaomicron, to the suckling period. | the adult human gut microbiota is dominated by two divisions of bacteria, the bacteroidetes and the firmicutes. assembly of this community begins at birth through processes that remain largely undefined. in this report, we examine the adaptations of bacteroides thetaiotaomicron, a prominent member of the adult distal intestinal microbiota, during the suckling and weaning periods. germ-free nmri mice were colonized at birth from their gnotobiotic mothers, who harbored this anaerobic gram-negative ... | 2006 | 16968696 |
| 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. | 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 ... | 2010 | 20944224 |
| application of quantitative real-time pcr for rapid identification of bacteroides fragilis group and related organisms in human wound samples. | our goal was to establish a quantitative real-time pcr (qrt-pcr) method to detect bacteroides fragilis group and related organisms from clinical specimens. compared to conventional anaerobic culture, qrt-pcr can provide accurate and more rapid detection and identification of b.-áfragilis group and similar species. b.-áfragilis group and related organisms are the most frequently isolated anaerobic pathogens from clinical samples. however, culture and phenotypic identification is quite time-consum ... | 2011 | 21439390 |
| aberrant response to commensal bacteroides thetaiotaomicron in crohn's disease: an ex vivo human organ culture study. | human ex vivo evidence indicating that an inappropriate immune response(s) to nonpathogenic bacteria contributes to disease pathogenesis in pediatric crohn's disease (cd) is limited. the aim of the present study was to compare and contrast the early innate immune response of pediatric "healthy" versus cd mucosa to pathogenic, probiotic, and commensal bacteria. | 2011 | 21484962 |
| sulfatases and a radical adomet enzyme are key for mucosal glycan foraging and fitness of a prominent human gut bacteroides. | the large-scale application of genomic and metagenomic sequencing technologies has yielded a number of insights about the metabolic potential of symbiotic human gut microbes. nevertheless, the molecular basis of the interactions between commensal bacteria and their host remained to be investigated. bacteria colonizing the mucosal layer that overlies the gut epithelium are exposed to highly sulfated glycans which can serve as potential nutrient sources but their high sulfate content usually preve ... | 2011 | 21507958 |
| interaction of bacteroides spp. with the kallikrein-kinin system. | many bacterial pathogens interfere with the contact system (kallikrein-kinin system) in human plasma. activation of this system has two consequences: cleavage of high molecular weight kininogen (hk) resulting in release of the potent proinflammatory peptide bradykinin and initiation of the intrinsic pathway of coagulation. in this study, two species of the gram-negative anaerobic commensal organism bacteroides - bacteroides fragilis and bacteroides thetaiotaomicron, were found to bind hk and fib ... | 2011 | 21527472 |
| Reactive cysteine in the active-site motif of Bacteroides thetaiotaomicron dipeptidyl peptidase III is a regulatory residue for the enzyme activity. | Abstract Dipeptidyl peptidase III (DPP III), a member of the metallopeptidase family M49, was considered as an exclusively eukaryotic enzyme involved in intracellular peptide catabolism and pain modulation. New data on genome sequences revealed only in 2003 the first prokaryotic orthologs, which showed low sequence similarity to eukaryotic ones and a cysteine residue in the zinc-binding motif HEXXGH. Here we report the cloning and heterologous expression of DPP III from the human gut symbiont ... | 2011 | 22111839 |