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PubMed1989

Bacteroides species from the oral cavity and oral-associated diseases of cats.

One hundred and sixty-seven strains of Bacteroides were isolated from 71 subcutaneous fight-wound abscesses of cats, 21 cases of feline pyothorax, normal gingival margins from 10 cats and 6 cases of feline gingivitis. Bacteroides species constituted (as a proportion of all anaerobic isolates examined) 44.5% from subcutaneous abscesses, 33.7% from pyothoraxes, 37.5% from normal gingiva and 27.7% from diseased gingiva. Bacteroides tectum comprised 43.7% or 73 of 167 strains, followed by the black- or brown-pigmented asaccharolytic feline species of B. gingivalis, B. salivosus and Group B, comprising 32.3% or 54 of 167 strains. B. heparinolyticus (some 10% or 17 of 167 strains) was the next most common species described. The remainder consisted of two strains of B. fragilis and 21 unspeciated strains. Bacteroides tectum was frequently isolated from subcutaneous abscesses (43.7%) and pyothoraxes (46.6%), and it constituted some 33% of anaerobic isolated from normal gingiva. Bacteroides heparinolyticus was more commonly encountered in purulent lesions (abscesses and pyothoraxes) than in the oral cavity.

Animals↗
PubMed2005

Molecular profiling of Bacteroides spp. in human feces by PCR-temperature gradient gel electrophoresis.

A group-specific PCR-based temperature gradient gel electrophoresis (TGGE) method was developed to study the population composition of genus Bacteroides in human gut. Highly reproducible and well-separated bands in TGGE fingerprints of ten unrelated human fecal samples showed complex and host-specific Bacteroides species composition. Dynamic monitoring over 22 months of samples from one healthy 10-year-old boy indicated a relatively stable population profile of Bacteroides. The species identity of each band in TGGE gel of this boy was also resolved via comigration analysis of sequenced inserts in a Bacteroides group-specific clone library. This work provides a rapid and effective technique for analyzing the species composition of Bacteroides in human gut.

Bacterial Typing Techniques↗
PubMed1989

Proteolytic activity in black-pigmented bacteroides species.

Black-pigmented Bacteroides species are frequently found in dentoalveolar abscesses. One general mechanism of bacterial virulence is the production of extracellular enzymes which degrade connective tissue or molecules associated with host defense. In this study the proteolytic activity of 18 bacterial strains from 9 black-pigmented Bacteroides species was examined. Bacteroides gingivalis degraded the greatest number of substrates studied and produced the highest levels of enzymatic activity. B. gingivalis was the only species that degraded collagen and produced high levels of enzymes that degraded N-benzoyl-DL-arginine (BANA) and N-CBz-glycyl-glycyl-arginine. Bacteroides intermedius degraded several substrates including PZ peptide. Bacteroides endodontalis produced enzymes that degraded beta-naphthylamide derivatives of glycylproline and glycylphenylalanine. There were considerable differences in enzyme production between strains of the same species. Such heterogeneity between strains in the production of proteolytic enzymes may be relevant to the in vivo infections produced in the host.

Azo Compounds↗
PubMed1998

Design and evaluation of a 16S rRNA-targeted oligonucleotide probe for specific detection and quantitation of human faecal Bacteroides populations.

Colonic Bacteroides include several species which, by their population level and activities, are significant contributers to the metabolic activity and health of man and animals. Yet, the understanding of their ecology has been hampered by the lack of highly specific and reliable enumeration techniques. Based on 16S rRNA sequence comparisons within the available database, we have designed an 18-mer oligonucleotide that targets a region common to-and specific for the Bacteroides-Porphyromonas-Prevotella group. We have tested the specificity of the probe and its usefulness for studies of human faecal samples. Under experimentally optimized hybridization conditions, the probe was shown to similarly recognize the rDNA obtained from 40 strains representing 8 species of the Bacteroides-Porphyromonas-Prevotella group. Importantly, it did not recognize 31 strains of microorganisms representing 8 genera of the dominant human faecal microbiota. Among selected colonies of dominant microorganisms of the faecal flora of two human individuals, strains identified as B. vulgatus by immunoblots using a species-specific monoclonal antibody were all detected by the probe. Colony hybridization was used to enumerate total Bacteroides-group microorganisms in faecal specimen from children and adults. The probe described therein was further used in quantitative RNA blots to monitor fluctuations of the Bacteroides-group versus Bifidobacterium genus in frozen faecal samples from a child between 85 and 125 days of age. It will be applicable to similar investigations of other anaerobic environments.

Adult↗
PubMed1984

Plasmid transfer from Escherichia coli to Bacteroides fragilis: differential expression of antibiotic resistance phenotypes.

A unique shuttle plasmid, pDP1, has been constructed to mediate gene transfer between Escherichia coli and the Gram-negative anaerobe Bacteroides fragilis. pDP1 contains the pBR322 replicon and the Bacteroides clindamycin resistance plasmid pCP1 linked to the transfer origin of the broad host range plasmid RK2. pDP1 can be transferred from E. coli to B. fragilis by the RK2 conjugation system even though RK2 itself is not maintained in the Bacteroides recipients. The antibiotic resistance and replication functions of pDP1 have been mapped by deletion analysis, and a 5-kilobase portion of the plasmid has been identified as the essential region for maintenance in Bacteroides. Comparison of the resistance conferred by pDP1 on E. coli and B. fragilis shows that antibiotic resistance genes are expressed differently in aerobic and anaerobic bacteria. These results document the feasibility of gene transfer from E. coli to B. fragilis and demonstrate the usefulness of this conjugation system to study genetic structure and expression in Bacteroides.

Bacteroides fragilis↗
PubMed2003

Reclassification of Bacteroides putredinis (Weinberg et al., 1937) in a new genus Alistipes gen. nov., as Alistipes putredinis comb. nov., and description of Alistipes finegoldii sp. nov., from human sources.

During studies on the bacteriology of appendicitis in children, we often isolated from inflamed and non-inflamed tissue samples, an unusual bile-resistant pigment-producing strictly anaerobic gram-negative rod. Phenotypically this organism resembles members of Bacteroides fragilis group of species, as it is resistant to bile and exhibits a special-potency-disk pattern (resistance to vancomycin, kanamycin and colistin) typical for the B. fragilis group. However, the production of brown pigment on media containing haemolysed blood and a cellular fatty acid composition dominated by iso-C15:0, suggests that the organism most closely resembles species of the genus Porphyromonas. However, the unidentified organism differs from porphyromonads by being bile-resistant and by not producing butyrate as a metabolic end-product. Comparative 16S ribosomal RNA gene sequencing studies show the unidentified organism represents a distinct sub-line, associated with but distinct from, the miss-classified species Bacteroides putredinis. The clustering of the unidentified bacterium with Bacteroides putredinis was statistically significant, but they displayed > 4% sequence divergence with each other. Chromosomal DNA-DNA pairing studies further confirmed the separateness of the unidentified bacterium and Bacteroides putredinis. Based on phenotypic and phylogenetic considerations, it is proposed that Bacteroides putredinis and the unidentified bacterium from human sources be classified in a new genus Alistipes, as Alistipes putredinis comb. nov. and Alistipes finegoldii sp. nov., respectively. The type strain of Alistipes finegoldii is CCUG 46020(T) (= AHN243(T)).

Appendicitis↗
PubMedDate not supplied

Bacteriophages of Bacteroides.

Sixty-eight bacteriophages specific for nine species (DNA homology groups) of Bacteroides were isolated from sewage. Four distinct morphological types were isolated, three of which had not previously been described. Attempts to use these phages to transduce Bacteroides fragilis were unsuccessful. A total of 91 phage-susceptible strains of Bacteroides were used with these phages in a study of the feasibility of developing a scheme for identification of Bacteroides species. Blind trials were performed with 10 B. fragilis-specific phages and a collection of over 200 bacterial strains, including 144 strains of B. fragilis. Of the strains of B. fragilis, 78% were identified correctly within 24 hr. A phage-carrier state, or pseudolysogeny, was observed with most of the phage-host systems, and this state was studied in detail with B. fragilis phage Bf-1. The presence of a thick capsule around some cells in a pure culture of a host strain appears to render these cells resistant to phage infection, thus perpetuating the carrier state. It is suggested that such capsules may play a role in the virulence of strains of Bacteroides.

Bacteriophages↗
PubMed1976

The polysaccharide capsule of Bacteroides fragilis subspecies fragilis: immunochemical and morphologic definition.

A large-molecular-weight capsular polysaccharide was isolated from strains of Bacteroides fragilis subspecies fragilis. By means of electron microscopy and staining with ruthenium red, the thick polysaccharide capsule was also visualized. With use of a radioactive antigen-binding assay, antibody to this capsular polysaccharide was demonstrated in antisera prepared in rabbits to each of eight strains of B. fragilis fragilis. Antibody of similar specificity was not found in antisera prepared to Bacteroides melaninogenicus or to strains of Bacteroides fragilis subspecies vulgatus and Bacteroides fragilis subspecies distasonis; such antibody was found in antisera to only one of two strains of Bacteroides fragilis subspecies thetaiotaomicron. The radioactive antigen-binding assay is a sensitive test for the detection of antibody to capsular polysaccharide. This polysaccharide antigen may form the basis of a serogrouping system for B. fragilis.

Antigen-Antibody Complex↗
PubMed1982

Dehydrogenase patterns in the taxonomy of Bacteroides.

The malate dehydrogenase (MDH) electrophoretic mobilities of 128 strains of bacteroides belonging to 17 species, including three subspecies of Bacteroides melaninogenicus and two subspecies of Bacteroides ruminicola, were examined. Amongst the pigmented bacteroides, the migration of this enzyme correlated well with recognized taxa, and only one strain, VPI 9085 was clearly different. Other species such as B. oralis, B. buccalis, B. denticola, B. pentosaceus, B. bivius, B. disiens and B. ruminicola were delineated by the combined use of MDH and glutamate dehydrogenase. Forty-three strains belonging to the 'B. fragilis group' differed from the above species in possessing glucose-6-phosphate dehydrogenase and 6-phosphogluconate dehydrogenase, and reference strains as well as fresh isolates were assigned to the correct species by the mobility pattern of these two enzymes. Other properties of MDH such as the pH optima for the oxidation of malate or the reduction of oxaloacetate were of limited taxonomic value. However, the alkaline stability of this enzyme at pH 9, 10 and 11 clearly differentiates the saccharolytic from the non-saccharolytic species of pigmented bacteroides with the latter showing highly stable enzymes with a half life greater than 50 min.

Bacteroides↗
PubMed1991

Multivariate analyses of fatty acid data from whole-cell methanolysates of Prevotella, Bacteroides and Porphyromonas spp.

The genus Bacteroides contains a number of biochemically and physiologically heterogeneous groups of organisms and needs taxonomic revision. In this study cellular fatty acids from a number of Bacteroides spp. were identified and quantified using gas chromatography and gas chromatography-mass spectrometry. The chemical data were then subjected to principal components analysis. In B. fragilis, which is the type species of the genus Bacteroides, C3-OH-iso17 was the predominant fatty acid (38.0%) and Cante15 was present in higher amounts (32.7%) than Ciso15 (14.6%). B. fragilis thus differed from all the other species examined: Prevotella (Bacteroides) buccae, P. (B.) oralis, P. (B.) oris, P. (B.) disiens, P. (B.) veroralis, P. (B.) heparinolytica and Porphyromonas (Bacteroides) endodontalis. Principal components analysis also enabled the closely related P. buccae, P. oralis and P. oris to be differentiated.

Bacteriolysis↗
PubMed1982

Impairment by Bacteroides species of opsonisation and phagocytosis of enterobacteria.

The ability of human polymorphonuclear leucocytes to phagocytose and kill Proteus mirabilis was impaired in vitro when the human serum, used to opsonise the target bacteria, was pretreated with cultures of various Bacteroides species. Live and dead, either heat-killed or clindamycin-treated, bacteroides cells elicited the same phenomenon. When bacteroides-treated serum was used to opsonise different Proteus species, the subsequent uptake of all strains by polymorphonuclear leucocytes was inhibited, whereas bacteroides-treated serum inhibited the uptake of some but not all of the test strains of Escherichia coli. The opsonic activity of untreated human serum was reduced when the classical complement pathway was inhibited by ethyleneglycol-bis-(beta-aminoethyl ether)N,N'-tetra-acetic acid (EGTA); subsequent treatment with bacteroides did not further reduce the opsonic activity of the serum for P. mirabilis.

Bacteroides↗
PubMed2005

Bacteroides coprosuis sp. nov., isolated from swine-manure storage pits.

Two Gram-negative, anaerobic, non-spore-forming, rod-shaped organisms were isolated from a swine-manure storage pit. Based on morphological and biochemical criteria, the strains were tentatively identified as belonging to the genus Bacteroides but they did not appear to correspond to any recognized species of the genus. Comparative 16S rRNA gene sequencing studies showed that the strains were related closely to each other and confirmed their placement in the genus Bacteroides, but sequence divergence values of >10 % from reference Bacteroides species demonstrated that the organisms from manure represent a novel species. Based on biochemical criteria and molecular genetic evidence, it is proposed that the unknown isolates from manure be assigned to a novel species of the genus Bacteroides, as Bacteroides coprosuis sp. nov. The type strain is PC139T (=CCUG 50528T=NRRL B-41113T).

Animals↗
PubMed1990

Characterization and physical mapping of plasmids of black-pigmented Bacteroides.

Eight species of black-pigmented Bacteroides (BPB) were examined for plasmid content. Three classes of plasmids with molecular sizes of 16.0 kilobase (kb), 5.4 kb and 5.0 kb were found in 7 of 125 Bacteroides intermedius strains. One strain each of Porphyromonas (former Bacteroides) asaccharolyticus and of Bacteroides levii were also shown to have plasmids. However, no plasmids were detected in 90 strains of Porphyromonas (Bacteroides) gingivalis. The plasmids were purified and digested with restriction endonucleases for restriction mapping. The maps obtained in this study have given us information on the scheme of constructing recombinants which may be usable as shuttle vectors, by the recombination of BPB and Escherichia coli plasmids.

Bacteroides↗
PubMed1995

Anti-bacteroides lipopolysaccharide IgG levels in healthy adults and sepsis patients.

Members of the genus Bacteroides greatly outnumber enterobacteria in the human colon and therefore represent a vast potential pool of biologically active LPS. An enzyme-linked immunosorbent assay was developed to estimate the distribution of IgG levels to LPS from B. fragilis, B. vulgatus, B. thetaiotaomicron and to a mixture of rough LPS from three enterobacteria and Pseudomonas aeruginosa in sera from 641 adult blood donors. By inhibition ELISA some cross-reactivity was demonstrated between the different anti-bacteroides LPS IgG, but with very little between the anti-bacteroides LPS IgG and the anti-enterobacterial/Pseudomonas LPS IgG. Serum IgG was measured daily over 5-9 day periods in 12 sepsis patients (6 survivors, 6 non-survivors) and in a healthy individual. In all patients IgG levels fluctuated to a greater extent than levels in a healthy subject. Variations all followed similar overall trends and indicated that exposure to bacteroides LPS had occurred. In 5 out of 6 survivors, IgG levels were rising at the end of the period, while 4 of the 6 non-survivors showed falls, with an exception showing increasing levels to B. fragilis LPS. In 5 out of 6 non-survivors, IgG levels against B. fragilis LPS were substantially higher than those against the other LPSs. In this small sample some trends in antibody kinetics have been recognised which suggest bacteroides LPS may be significant in sepsis, and indicate that this study should be extended.

Antibodies, Bacterial↗
PubMed1999

Design of cluster-specific 16S rDNA oligonucleotide probes to identify bacteria of the Bacteroides subgroup harbored in human feces.

To develop a new simple method for identification of bacteria in the Bacteroides subgroup isolated from human feces, we designed a panel of four 16S rDNA-targeted oligonucleotide probes specific for each cluster of the Bacteroides subgroup. The probes Bac and bacvul were targeted to the Bacteroides cluster, and the probes Pre and Por have their target regions characteristic to those of the Prevotella cluster and the Porphyromonas cluster, respectively. The probes presented in this work were constructed to be specific for reference strains in each cluster of the Bacteroides subgroup and were not cross-hybridized with other major intestinal bacteria. The use of combination of these four probes will faciliate the identification of the clusters of the Bacteroides subgroup harbored in the intestine as compared to biological and biochemical testings.

Bacteroides↗
PubMed1990

Cytotoxic and immunostimulatory effects of Bacteroides cell products.

The etiologic role of Bacteroides in both periodontal and periapical infections has been well documented, with current interest focusing on the specific pathogenic mechanisms involved. The effects of cell fractions derived from Bacteroides gingivalis (BG), Bacteroides intermedius (BI), and Bacteroides asaccharolyticus (BA) have been studied in vitro through: an assessment of the direct cytotoxic effects on human gingival fibroblasts using a tetrazolium dye reduction assay, an evaluation of murine lymphocyte stimulation and interleukin-1 release, and the induction of human lymphocyte-mediated cytotoxicity. Both BG and BI stimulated interleukin-1 release (P less than 0.001), while BA, a nonoral organism, was not significantly active in this respect. Only BG sonicates were able to induce lymphocyte-mediated cytotoxicity (P less than 0.005). All three Bacteroides species demonstrated direct cytotoxic effects on cultured gingival fibroblasts, and these effects were related to the relative protein content and endotoxin activity of the sonicate preparations for each organism. These data show that BG and BI possess factors which may enhance their virulence through activities not shared with BA.

Analysis of Variance↗
PubMed2006

Three enzymes for trehalose synthesis in Bradyrhizobium cultured bacteria and in bacteroids from soybean nodules.

alpha,alpha-Trehalose is a disaccharide accumulated by many microorganisms, including rhizobia, and a common role for trehalose is protection of membrane and protein structure during periods of stress, such as desiccation. Cultured Bradyrhizobium japonicum and B. elkanii were found to have three enzymes for trehalose synthesis: trehalose synthase (TS), maltooligosyltrehalose synthase (MOTS), and trehalose-6-phosphate synthetase. The activity level of the latter enzyme was much higher than those of the other two in cultured bacteria, but the reverse was true in bacteroids from nodules. Although TS was the dominant enzyme in bacteroids, the source of maltose, the substrate for TS, is not clear; i.e., the maltose concentration in nodules was very low and no maltose was formed by bacteroid protein preparations from maltooligosaccharides. Because bacteroid protein preparations contained high trehalase activity, it was imperative to inhibit this enzyme in studies of TS and MOTS in bacteroids. Validamycin A, a commonly used trehalase inhibitor, was found to also inhibit TS and MOTS, and other trehalase inhibitors, such as trehazolin, must be used in studies of these enzymes in nodules. The results of a survey of five other species of rhizobia indicated that most species sampled had only one major mechanism for trehalose synthesis. The presence of three totally independent mechanisms for the synthesis of trehalose by Bradyrhizobium species suggests that this disaccharide is important in the function of this organism both in the free-living state and in symbiosis.

Bacteroides↗
PubMed2001

Characterization of the 13-kilobase ermF region of the Bacteroides conjugative transposon CTnDOT.

The conjugative transposon CTnDOT is virtually identical over most of its length to another conjugative transposon, CTnERL, except that CTnDOT carries an ermF gene that is not found on CTnERL. In this report, we show that the region containing ermF appears to consist of a 13-kb chimera composed of at least one class I composite transposon and a mobilizable transposon (MTn). Although the ermF region contains genes also carried on Bacteroides transposons Tn4351 and Tn4551, it does not contain the IS4351 element which is found on these transposons. In CTnDOT, insertion of the ermF region occurred near a stem-loop structure at the end of orf2, an open reading frame located immediately downstream of the integrase (int) gene of CTnDOT, and in a region known to be important for excision of CTnERL and CTnDOT. The chimera that comprises the ermF region can apparently no longer excise and circularize, but it contains a functional mobilization region related to that described for the Bacteroides MTn Tn4399. Analysis of 19 independent Bacteroides isolates showed that the ermF region is located in the same position in all of the strains analyzed and that the compositions of the ermF region are almost identical in these strains. Therefore, it appears that CTnDOT-like elements present in community and clinical isolates of Bacteroides were derived from a common ancestor and proliferated in the diverse Bacteroides population.

Anti-Bacterial Agents↗