Human gut Bacteroides species produce different types of toxins that antagonize closely related members of the gut microbiota. Some are toxic effectors delivered by type VI secretion systems, and others are non-contact-dependent secreted antimicrobial proteins. Many strains of Bacteroides fragilis secrete antimicrobial molecules, but only one of these toxins has been described to date (Bacteroi...

The barley grasses (Hordeum glaucum Steud. and Hordeum leporinum Link.) are important weeds of crops and pastures in South Australia. Populations of both species have evolved resistance to paraquat, primarily following intensive use of paraquat for winter weed control in lucerne (Medicago sativa L.) crops. In the past few years, agricultural consultants have been reporting an increase in proble...

The susceptibilities of recent clinical isolates of anaerobic bacteria from two community hospitals were determined. Thirty percent of pigmented Bacteroides species and bile-sensitive, nonpigmented Bacteroides species produced penicillinase and were resistant to amoxicillin. Cefoxitin and clindamycin showed good activity against most strains, with the exception of rare isolates of the Bacteroid...

BACKGROUND AND PURPOSE Bacteroides fragilis is a virulent anaerobic pathogen, resulting in considerable mortality. This study was conducted to investigate the clinical characteristics, significance of polymicrobial bacteremia, and treatment outcomes of B. fragilis bacteremia. METHODS This retrospective analysis enrolled 199 adult patients with B. fragilis bacteremia, who were admitted to hosp...

Accurate identification of Bacteroides species is often problematic. Therefore, we used a polymerase chain reaction (PCR) fingerprinting technique with either a single nonspecific primer derived from tDNA intergenic spacer or a single primer that anneals to mini- and microsatellite DNA sequences to compare 34 clinical isolates of B. fragilis and 21 clinical isolates of B. thetaiotaomicron from ...

Bacteroides species are nearly half of the fecal flora community and some are host symbionts crucial to host nutrition and systemic immunity. Among Bacteroides species B. fragilis strains are considered to be the opportunistic ones, being the most isolated anaerobic bacteria in clinical samples. Cell-free supernatants of 65 B. fragilis strains were assayed and they were capable of inducing vacu...

Evidences have shown that dysbiosis could promote the progression of colorectal cancer (CRC). However, the association of dysbiosis and prognosis of CRC is barely investigated. Therefore, we used 16S rRNA gene sequencing approach to determine differences in microbiota among tumor tissues of different prognosis and found that Fusobacterium nucleatum and Bacteroides fragilis were more abundant in...

Susceptibility testing was performed on Dientamoeba fragilis ATCC 30948 in a dixenic culture with Klebsiella pneumoniae and Bacteroides vulgatus. D. fragilis was cocultured with the bacteria in TYGM-9 medium (ATCC medium 1171). The activities of antiparasitic drugs were assessed by counting viable D. fragilis trophozoites with a hemacytometer by trypan blue exclusion. The minimal amebicidal con...

Erythromycin and cefamandole have exhibited synergistic activity against eight strains of Bacteroides fragilis subsp. fragilis. In concentrations of only 0.25 to 0.5 mug of erythromycin per ml (easily obtainable with oral therapy), less than 0.4 mug (0.015 to 1.0) of cefamandole per ml inhibited the B. fragilis strains. In the presence of the erythromycin, the potency of cefamandole was increas...

The presence of enterotoxigenic Bacteroides fragilis and nontoxigenic B. fragilis (NTBF) among 109 strains isolated from 1980-2008 in Brazil were investigated by PCR. One strain, representing 0.9% of the total analyzed strains, harbored the bft gene which was identified as bft-1 isoform based on PCR-RFLP and sequencing. Forty-nine strains (44.9%) exhibited the NTBF pattern III which possesses t...