Enterococcaceae

Abstract: Bacteria were isolated from the crop and midgut of field collected Bactrocera cacuminata (Hering) and Bactrocera tryoni (Froggatt) (Diptera: Tephritidae). Two methods were used, firstly isolation onto two types of bacteriological culture media (PYEA and TSA) and identification using the API-20E diagnostic kit, and secondly, analysis of samples using the 16S rRNA gene molecular diagnostic method. Using the API-20E method, 10 genera and 17 species of bacteria in the family Enterobacteriaceae were identified from cultures growing on the nutrient agar. The dominant species in both the crop and midgut were Citrobacter freundii, Enterobacter cloacae and Klebsiella oxytoca. Providencia rettgeri, Klebsiella pneumoniae ssp ozaenae and Serratia marcescens were isolated from B. tryoni only. Using the molecular cloning technique that is based on 16S rRNA gene sequences, five bacteria classes were dignosed — Alpha-, Beta-, Gamma- and Delta- Proteobacteria and Firmicutes — including five families, Leuconostocaceae, Enterococcaceae, Acetobacteriaceae, Comamonadaceae and Enterobacteriaceae. The bacteria affiliated with Firmicutes were found mainly in the crop while the Gammaproteobacteria, especially the family Enterobacteriaceae, was dominant in the midgut. This paper presents results from the first known application of molecular cloning techniques to study bacteria within tephritid species and the first record of Firmicutes bacteria in these flies.

Abstract: BACKGROUND This study aimed to identify the cultivable bacteria inhabiting the intestinal tract of adult oriental fruit flies (Bactrocera dorsalis) from laboratory-reared, laboratory sterile sugar-reared, and field-collected populations, and to evaluate the attractiveness of the metabolites produced by the above bacteria to their hosts. RESULTS Fifteen bacterial isolates chosen from the three populations were determined at species level. These 15 strains were cultured and the attractiveness of the whole Luria–Bertani broth, filtered and autoclaved supernatants to B. dorsalis adults was determined using bioassays. The bioassays showed that all bacterial strains were significantly more attractive to B. dorsalis adults than the media-only control. Among them, Bacillus cereus, Enterococcus faecalis, Enterobacter cloacae and Citrobacter freundii were the most attractive bacteria. Furthermore, results of a subsequent field test showed that the six bacterial strains were significantly more attractive than the control, with B. cereus and E. faecalis attracting significantly more flies. CONCLUSIONS A cultivable bacterial community composed of Enterobacteriaceae, Enterococcaceae, and Bacillaceae was identified in the intestinal tract of B. dorsalis. Metabolites from B. cereus attracted the greatest number of B. dorsalis adults in the laboratory and field. These results provide useful information for the development of bacterial biocontrol agents or implementation as an insecticide. © 2013 Society of Chemical Industry

Abstract: For detection of most members of the Enterococcaceae, the specificity of a novel oligonucleotide microarray (ECC-PhyloChip) consisting of 41 hierarchically nested 16S or 23S rRNA gene-targeted probes was evaluated with 23 pure cultures (including 19 Enterococcus species). Target nucleic acids were prepared by PCR amplification of a 4.5-kb DNA fragment containing large parts of the 16S and 23S rRNA genes and were subsequently labeled fluorescently by random priming. Each tested member of the Enterococcaceae was correctly identified on the basis of its unique microarray hybridization pattern. The evaluated ECC-PhyloChip was successfully applied for identification of Enterococcus faecium and Enterococcus faecalis in artificially contaminated milk samples demonstrating the utility of the ECC-PhyloChip for parallel identification and differentiation of Enterococcus species in food samples.

Abstract: Purpose. To detect the alteration of gut bacteria in children with ALL and analyse the impact of short-term-use of antibiotics on the changes caused by ALL. Methodology. We collected faecal samples from both children with ALL and healthy children. According to their medication history with antibiotics, we classified the samples into ALL+ATBx, ALL, CON+ATBx and CON groups. Next-generation sequencing was performed to identify the gut bacteria according to the MiSeq platform. The Shannon index, Simpson index, Chao index and Ace index were used to represent the alpha diversity of gut bacteria. The beta diversity was estimated using the principles of co-ordinate analysis and non-metric multi-dimensional scaling. The taxon composition and presence of biomarkers were then determined through bioinformatics. Results. With regard to alpha diversity, the Shannon index and Simpson index differed significantly between the ALL and CON groups, as well as the CON+ATBx and CON groups, but not the ALL+ATBx and CON+ATBx groups. With regard to beta diversity, the ALL and CON separated clearly into clusters, as did ALL+ATBx and CON+ATBx. There were differences in composition among the four groups at different taxonomy hierarchies. More bacteria showed an obvious difference between the paired groups ALL and CON than did for the paired groups ALL+ATBx and CON+ATBx. The area under the receiver operating characteristic curves for Bacteroidales and Enterococcaceae used to predict ALL were 0.735 and 0.724, respectively. Conclusion. ALL induced structural changes of the gut microbiota, with the alpha diversity being significantly weakened by antibiotics, but not beta diversity. Bacteroidales and Enterococcaceae can be referred to as biomarkers for ALL.