Project description:Light yellow-pigmented (strain PQ1) and yellow-pigmented (strain PQ2), gram-positive, non-spore-forming, nonmotile bacteria consisting of pairs or chains of cocci were isolated from the bile of a patient with cholecystitis (PQ1) and the peritoneal dialysate of another patient with peritonitis (PQ2). Morphologically and biochemically, the organisms phenotypically belonged to the genus Eterococcus. Whole-cell protein (WCP) analysis and sequence analysis of a segment of the 16S rRNA gene suggested that they are new species within the genus Enterococcus. PQ1 and PQ2 displayed less than 70% identities to other enterococcal species by WCP analysis. Sequence analysis showed that PQ1 shared the highest level of sequence similarity with Enterococcus raffinosus and E. malodoratus (sequence similarities of 99.8% to these two species). Sequence analysis of PQ2 showed that it had the highest degrees of sequence identity with the group I enterococci E. malodoratus (98.7%), E. raffinosus (98.6%), E. avium (98.6%), and E. pseudoavium (98.6%). PQ1 and PQ2 can be differentiated from the other Enterococcus spp. in groups II, III, IV, and V by their phenotypic characteristics: PQ1 and PQ2 produce acid from mannitol and sorbose and do not hydrolyze arginine, placing them in group I. The yellow pigmentation differentiates these strains from the other group I enterococci. PQ1 and PQ2 can be differentiated from each other since PQ1 does not produce acid from arabinose, whereas PQ2 does. Also, PQ1 is Enterococcus Accuprobe assay positive and pyrrolidonyl-beta-naphthylamide hydrolysis positive, whereas PQ2 is negative by these assays. The name Enterococcus gilvus sp. nov. is proposed for strain PQ1, and the name Enterococcus pallens sp. nov. is proposed for strain PQ2. Type strains have been deposited in culture collections as E. gilvus ATCC BAA-350 (CCUG 45553) and E. pallens ATCC BAA-351 (CCUG 45554).
Project description:Young adult N2 Caenorhabditis elegans were infected with Enterococcus faecalis or Enterococcus faecium for 8 h to determine the transcriptional host response to each enterococcal species. Analysis of differential gene expression in C. elegans young adults exposed to four different bacteria: heat-killed Escherichia coli strain OP50 (control), wild-type E. faecalis MMH594, wild-type E. faecium E007, or Bacillus subtilis PY79 (sigF::kan). Samples were analyzed at 8 hours after exposure to the different bacteria. These studies identified C. elegans genes induced by pathogen infection. Brain-heart infusion agar plates (10 ug/ml kanamycin) were used.
Project description:As a reference laboratory, the Streptococcus Laboratory at the Centers for Disease Control and Prevention (CDC) is frequently asked to confirm the identity of unusual or difficult-to-identify catalase-negative, gram-positive cocci. In order to accomplish the precise identification of these microorganisms, we have systematically applied analysis of whole-cell protein profiles (WCPP) and DNA-DNA reassociation experiments, in conjunction with conventional physiological tests. Using this approach, we recently focused on the characterization of three strains resembling the physiological groups I (strain SS-1730), II (strain SS-1729), and IV (strain SS-1728) of enterococcal species. Two strains were isolated from human blood, and one was isolated from human brain tissue. The results of physiological testing were not consistent enough to allow confident inclusion of the strains in any of the known enterococcal species. Resistance to vancomycin was detected in one of the strains (SS-1729). Analysis of WCPP showed unique profiles for each strain, which were not similar to the profiles of any previously described Enterococcus species. 16S ribosomal DNA (rDNA) sequencing results revealed three new taxa within the genus ENTEROCOCCUS: The results of DNA-DNA relatedness experiments were consistent with the results of WCPP analysis and 16S rDNA sequencing, since the percentages of homology with all 25 known species of Enterococcus were lower than 70%. Overall, the results indicate that these three strains constitute three new species of Enterococcus identified from human clinical sources, including one that harbors the vanA gene. The isolates were provisionally designated Enterococcus sp. nov. CDC Proposed New Species of Enterococcus 1 (CDC PNS-E1), type strain SS-1728(T) (= ATCC BAA-780(T) = CCUG 47860(T)); Enterococcus sp. nov. CDC PNS-E2, type strain SS-1729(T) (= ATCC BAA-781(T) = CCUG 47861(T)); and Enterococcus sp. nov. CDC PNS-E3, type strain SS-1730(T) (= ATCC BAA-782(T) = CCUG 47862(T)).
Project description:Strain Marseille-Q0835T is an aerobic, non-motile and non-spore-forming Gram-positive coccus isolated from the stools of a Burkinabe woman. In this report, we present its phenotypic description including MALDI-TOF mass spectrometry analysis and genome sequencing. Strain Marseille-Q0835T; 2.9768-Mb genome exhibited a 41.9 mol% G+C content and 2699 predicted genes. Considering phenotypic features and comparative genome studies, we propose the strain Marseille-Q0835T as the type strain of Enterococcus burkinafasonensis sp. nov., a new species within the family Enterococcaceae.
Project description:Inappropriate response to normal intestinal bacteria is involved in the development of Inflammatory Bowel Diseases (IBD, e.g. Crohn’s Disease (CD), ulcerative colitis (UC)) and variations in the host genome may mediate this process. IL-10-/- mice develop CD-like colitis mainly in the colon, in part due to inappropriate responses to normal intestinal bacteria including Enterococcus strains. Comprehensive characterization of changes in gene expression associated with the observed inflammation in the IL-10-/- mouse model has yet to be reported. Our aim was to characterize changes in colonic gene expression in IL-10-/- and C57BL/6J (C57; control) mice resulting from oral bacterial inoculation with 12 Enterococcus faecalis and faecium (EF) strains isolated from calves or poultry, complex intestinal flora (CIF) collected from healthy control mice, or a mixture of the two (EF•CIF). At 12 weeks of age, total RNA extracted from intact colon was hybridized to Agilent 44k mouse arrays. Lists of differentially expressed genes were generated using linear models for microarray analysis (Bioconductor), and genes clustered using GeneSpring GX and Ingenuity Pathways Analysis software. Intestinal inflammation was increased in IL-10-/- mice as a result of inoculation, with the strongest effect being in the EF and EF.CIF groups; expression of >4,000 gene probes was altered in colon tissue compared with similarly inoculated C57 mice. Genes differentially expressed in IL-10-/- mice as a result of EF or EF.CIF inoculation were associated with the following pathways: inflammatory disease (111 genes differentially expressed), immune response (209 genes), antigen presentation (11 genes, particularly major histocompatability complex Class II), fatty acid metabolism (30 genes) and detoxification (31 genes). Our results suggest that the colonic inflammation in EF and EF.CIF-inoculated IL-10-/- mice is mediated by mechanisms similar to those of human IBD, in particular CD. Example logFC calculation This example describes the calculation of the fold-change value (logFC) for a single spot (in this case, spot 27222) for a single comparison. This calculation method was applied to generate all of the comparison data shown in the supplementary data files. The comparison in question is for: colon tissue from C57BL/6J mouse with EF.CIF treatment (represented by duplicate samples GSM307282 (Title: C57BL/6J_Colon_EF.CIF_Rep1_(Pool17)) and GSM307283 (Title: C57BL/6J_Colon_EF.CIF_Rep2_(Pool18)) vs. colon tissue from C57BL/6J mouse under conventional conditions (represented by duplicate samples GSM307270 (Title: C57BL/6J_Colon_Conventional_Rep1_(Pool5)) and GSM307271 (Title: C57BL/6J_Colon_Conventional_Rep2_(Pool6)) Important Note: Limma analysis maps the treatments on each slide to the M values which are by convention always log2(R) - log2(G). Because this experiment is a reference design, with the reference RNA always Cy5 (i.e. red, channel 2) and the treatment sample Cy3 (i.e. green, channel 1), and we are interested in the values of the treatment samples compared with the reference, the M values in the data files are displayed as log2(G) - log2(R) The average expression is what is important here, which is calculated from the normalized M values for the appropriate comparison of interest as follows: [1] Mean value for Spot 27222, for each treatment: C57BL/6J mouse, EF.CIF: = mean (0.26363587 (GSM307282), 0.05084283 (GSM307283)) = 0.15723935 C57BL/6J mouse, conventional = mean (1.42951674 (GSM307270),1.15444106 (GSM307271)) = 1.2919789 [2] Calculation of LogFC for the comparison of interest: The contrast of interest is C57BL/6J: EF.CIF vs Conventional, so by performing a subtraction of these values for the comparison of interest (i.e. (mean for EF.CIF) - (mean for Conventional), the common reference is cancelled out, thus: C57BL/6J: EF.CIF vs Conventional = 0.15723935 - 1.2919789 = -1.13473955 So, the fold-change value (logFC) for spot 27222 for the comparison in question (C57BL/6J: EF.CIF vs. Conventional) is: -1.13473955
Project description:A group of gram positive bacteria that share the characteristic of fermenting hexose sugars to lactic acid are generally referred to as lactic acid bacteria (LAB). Enterococcus faecalis is one of the widely studied LABs due to a multiutude of reasons. On the one hand, it plays an important role in dairy industry, being for example a starter in cheese cultures. On the other hand, it accounts for a large part of the infections caused by the LABs in hospital environments. During the past few years, it developed resistance against most of the major antibiotics. Here, in an attempt to study its adaptive metabolism, a glutamine synthetase mutant (∆glnA) of E. faecalis was subjected to pH shift and the results from the integrative analysis of its metabolic network were compared to those of the wild type. The proteome data generated in this study were used to constrain the genome-scale metabolic network at two pH level, aiming to reduce the solution space and improve the accuracy of model simulation. This data particularly helped to come up with a new design for the amino acid transport system in the genome-scale model, resulting in an accurate reproduction of the metabolic behaviour of E. faecalis.