The sequence homologous to the predicted type I restriction-modification enzyme from E. coli O127:H6 strain E2348/69 was statistically associated with strains isolated from humans in comparison with strains isolated from bovines. All the other fragments were associated with neither pathotype nor host. Shen et al. (2004) first described the PAI ICL3 locus

in the O113:H21 VTEC strain CL3. PAI ICL3 is a hybrid genomic region composed of genes similar to EDL933 (serotype O157:H7) O islands 122 and 48, Yersinia pestis, Ralstonia solanacearum, Pseudomonas syringae, Fusobacterium nucleatum, Bacillus subtilis, S. enterica, and Sulfolobus Gefitinib price tokodaii (Table 3). To date, PAI ICL3 has been detected only in eae-negative VTEC strains associated with diseases in humans and never in any other pathogenic or commensal E. coli, and it may therefore be used as a new marker for those strains (Girardeau et al., 2009). As several genes of PAI ICL3 have been identified here in the bovine EHEC

strain 4276 of serogroup O26, their distribution was studied with specific PCRs in the collection of human and bovine Pictilisib EHEC and EPEC strains. Eight strains (three human EPEC and five human and bovine EHEC strains) were found to be positive for several PCRs targeting different genes of the PAI ICL3 locus (Table 3). According to their PFGE pattern, these eight strains are not closely related. Indeed, they are present in the five clusters revealed by the PFGE dendrogram with a similarity of 45%, suggesting that these genes were horizontally acquired. No statistical difference was associated with the pathotype and/or the host origin (P < 0.01). This genomic island can in fact be divided into four parts: two genomic segments (GS-I inserted and GS-II including two genes of OI-122) bordered by OI-48 segments either side (Shen et al., 2004). The eight strains were tested positive

here with the PCRs for the three genes of GS-I and CYTH4 for all six genes of the two OI-48 segments. To verify whether Z1640 gene is intact or not, we performed two PCRs: one PCR targeting the Z1640-1 and Z1640-3 sequences (using Z1640-F and Z1640-R primers) and one PCR targeting the Z1640-1 and S1 sequences (using Z1640-F and S1-bis-R primers). The eight strains were positive only with the Z1640/S1 PCR. On the other hand, only the S4 gene of GS-II was detected in all eight strains, while the other genes (including S10 and S11 genes of OI-122) were detected in none to six strains only. Several serogroups of EHEC strains (e.g. O5, O26, O111, O118) can infect both humans and calves and can also be found in healthy cattle. Factors implicated in host specificity have been identified for some other pathogenic E. coli strains, but not for EHEC strains. Such factors could be based on proteins intervening in the colonization stage (adhesins, for example).

It has the ability to interact with and invade host cells, and then to live within these cells (Ly & Casanova, 2007). We report that the two Lactobacillus strains display killing activity against G. vaginalis, UPEC and S. typhimurium by substances present in the cell-free culture supernatants (CFCSs). Moreover, our results show that the main metabolic product of Lactobacillus, lactic acid, displays

no killing activity at the concentration present in Lactobacillus cultures, whereas hydrogen peroxide dose-dependently killed these pathogens. We also provide evidence that at the concentration present in Lactobacillus cultures, lactic acid considerably enhances the killing activity of hydrogen peroxide. The prototype UPEC strain CFT073 (Mobley et al., 1990) and S. typhimurium SL1344 Selleck DAPT (Finlay & Falkow, 1990) were used. Bacteria were Transmembrane Transporters modulator cultured in Luria–Bertani (LB) agar (Difco Laboratories, Detroit, MI) and incubated at 37 °C for 24 h. Gardnerella vaginalis DSM 4944 was grown on Gardnerella agar plates purchased from BioMerieux (Lyon, France), as described previously (Atassi et al., 2006a, b). Bacteria were suspended in pH 7.0 buffered sodium chloride-peptone solution at about 106 CFU mL−1. Five hundred microliters of the prepared suspension was spread on the agar plate. The inoculated plates were dried under a sterile laminar airflow. The agar plates were then

incubated under anaerobic conditions in a sealed anaerobic jar (Becton Dickinson) at 37 °C for up to 36 h. Before being used, G. vaginalis was subcultured in brain–heart infusion supplemented with yeast

extract (1%), maltose (0.1%), glucose (0.1%) and horse serum (10%) under anaerobic conditions in a sealed anaerobic jar at 37 °C for up to 36 h. For each experiment, bacteria were subcultured for the exponential phase in appropriate media. Lactobacillus johnsonii strain NCC533 was from the Nestec Research Center PAK6 at Vers-chez-les-Blanc (Switzerland). The L. gasseri KS120.1 strain isolated from the vaginal flora of a healthy woman (Department of Obstetrics and Gynecology, Zurich University Hospital, Switzerland) was from Medinova (Zurich, Switzerland) (Atassi et al., 2006a, b). All the Lactobacillus strains were grown in De Man, Rogosa, Sharpe (MRS) broth (Biokar Diagnostic, Beauvais, France) for 24 h at 37 °C. The Lactobacillus culture was adjusted to pH 4.5 by adding HCl or NaOH to ensure standardized conditions. Cultures of the Lactobacillus strains (24 h) were centrifuged at 10 000 g for 30 min at 4 °C. Bacteria were collected and washed three times with sterile phosphate-buffered saline (Coconnier et al., 1997, 2000). Supernatants of the centrifuged cultures were collected and passed through a sterile 0.22-μm filter unit Millex GS (Millipore, Molsheim, France).

It has the ability to interact with and invade host cells, and then to live within these cells (Ly & Casanova, 2007). We report that the two Lactobacillus strains display killing activity against G. vaginalis, UPEC and S. typhimurium by substances present in the cell-free culture supernatants (CFCSs). Moreover, our results show that the main metabolic product of Lactobacillus, lactic acid, displays

no killing activity at the concentration present in Lactobacillus cultures, whereas hydrogen peroxide dose-dependently killed these pathogens. We also provide evidence that at the concentration present in Lactobacillus cultures, lactic acid considerably enhances the killing activity of hydrogen peroxide. The prototype UPEC strain CFT073 (Mobley et al., 1990) and S. typhimurium SL1344 Cobimetinib (Finlay & Falkow, 1990) were used. Bacteria were Y-27632 ic50 cultured in Luria–Bertani (LB) agar (Difco Laboratories, Detroit, MI) and incubated at 37 °C for 24 h. Gardnerella vaginalis DSM 4944 was grown on Gardnerella agar plates purchased from BioMerieux (Lyon, France), as described previously (Atassi et al., 2006a, b). Bacteria were suspended in pH 7.0 buffered sodium chloride-peptone solution at about 106 CFU mL−1. Five hundred microliters of the prepared suspension was spread on the agar plate. The inoculated plates were dried under a sterile laminar airflow. The agar plates were then

incubated under anaerobic conditions in a sealed anaerobic jar (Becton Dickinson) at 37 °C for up to 36 h. Before being used, G. vaginalis was subcultured in brain–heart infusion supplemented with yeast

extract (1%), maltose (0.1%), glucose (0.1%) and horse serum (10%) under anaerobic conditions in a sealed anaerobic jar at 37 °C for up to 36 h. For each experiment, bacteria were subcultured for the exponential phase in appropriate media. Lactobacillus johnsonii strain NCC533 was from the Nestec Research Center oxyclozanide at Vers-chez-les-Blanc (Switzerland). The L. gasseri KS120.1 strain isolated from the vaginal flora of a healthy woman (Department of Obstetrics and Gynecology, Zurich University Hospital, Switzerland) was from Medinova (Zurich, Switzerland) (Atassi et al., 2006a, b). All the Lactobacillus strains were grown in De Man, Rogosa, Sharpe (MRS) broth (Biokar Diagnostic, Beauvais, France) for 24 h at 37 °C. The Lactobacillus culture was adjusted to pH 4.5 by adding HCl or NaOH to ensure standardized conditions. Cultures of the Lactobacillus strains (24 h) were centrifuged at 10 000 g for 30 min at 4 °C. Bacteria were collected and washed three times with sterile phosphate-buffered saline (Coconnier et al., 1997, 2000). Supernatants of the centrifuged cultures were collected and passed through a sterile 0.22-μm filter unit Millex GS (Millipore, Molsheim, France).

It has the ability to interact with and invade host cells, and then to live within these cells (Ly & Casanova, 2007). We report that the two Lactobacillus strains display killing activity against G. vaginalis, UPEC and S. typhimurium by substances present in the cell-free culture supernatants (CFCSs). Moreover, our results show that the main metabolic product of Lactobacillus, lactic acid, displays

no killing activity at the concentration present in Lactobacillus cultures, whereas hydrogen peroxide dose-dependently killed these pathogens. We also provide evidence that at the concentration present in Lactobacillus cultures, lactic acid considerably enhances the killing activity of hydrogen peroxide. The prototype UPEC strain CFT073 (Mobley et al., 1990) and S. typhimurium SL1344 GSK1120212 supplier (Finlay & Falkow, 1990) were used. Bacteria were SCH772984 chemical structure cultured in Luria–Bertani (LB) agar (Difco Laboratories, Detroit, MI) and incubated at 37 °C for 24 h. Gardnerella vaginalis DSM 4944 was grown on Gardnerella agar plates purchased from BioMerieux (Lyon, France), as described previously (Atassi et al., 2006a, b). Bacteria were suspended in pH 7.0 buffered sodium chloride-peptone solution at about 106 CFU mL−1. Five hundred microliters of the prepared suspension was spread on the agar plate. The inoculated plates were dried under a sterile laminar airflow. The agar plates were then

incubated under anaerobic conditions in a sealed anaerobic jar (Becton Dickinson) at 37 °C for up to 36 h. Before being used, G. vaginalis was subcultured in brain–heart infusion supplemented with yeast

extract (1%), maltose (0.1%), glucose (0.1%) and horse serum (10%) under anaerobic conditions in a sealed anaerobic jar at 37 °C for up to 36 h. For each experiment, bacteria were subcultured for the exponential phase in appropriate media. Lactobacillus johnsonii strain NCC533 was from the Nestec Research Center HAS1 at Vers-chez-les-Blanc (Switzerland). The L. gasseri KS120.1 strain isolated from the vaginal flora of a healthy woman (Department of Obstetrics and Gynecology, Zurich University Hospital, Switzerland) was from Medinova (Zurich, Switzerland) (Atassi et al., 2006a, b). All the Lactobacillus strains were grown in De Man, Rogosa, Sharpe (MRS) broth (Biokar Diagnostic, Beauvais, France) for 24 h at 37 °C. The Lactobacillus culture was adjusted to pH 4.5 by adding HCl or NaOH to ensure standardized conditions. Cultures of the Lactobacillus strains (24 h) were centrifuged at 10 000 g for 30 min at 4 °C. Bacteria were collected and washed three times with sterile phosphate-buffered saline (Coconnier et al., 1997, 2000). Supernatants of the centrifuged cultures were collected and passed through a sterile 0.22-μm filter unit Millex GS (Millipore, Molsheim, France).