0×105

cells/well). Culture supernatants were removed and the monolayer was washed once with PBS buffer. Fresh bacterial cells cultured to an OD600 of 1.0 were diluted in DMEM with or without DSF at a final concentration of 50 μM, which were then added to the HeLa cell monolayers at a multiplicity of infection (MOI) about 1000, and gentamycin was added at different final concentrations as indicated. Cytotoxicity was determined by measuring the release of the cytosolic AG-881 enzyme lactate dehydrogenase (LDH) into supernatants using the cytotoxicity detection kit (Roche). Acknowledgements The funding for this work was provided by the Biomedical Research Council, the Agency of Science, Technology and Research (A*Star), Singapore. Electronic supplementary material Additional file 1: Figure S1: Real-time PCR analysis of DSF effect on transcriptional expression of selected genes in B. Selleck AZD5363 cereus 10987. Table S1. The genes with increased or decreased expression in B. cereus 10987 after treatment with 50 μM DSF. Figure S2. The bacterial growth rate in the presence and absence of 50 μM DSF or its analogue. Figure S3. Effect of DSF signal and rhamnolipid on the growth rate of B. thuringiensis. Table S2. Bacterial strains used in this study. (DOCX 107 KB) References 1. Livermore DM: The need for new

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