Project description:RNA-Seq of 3iL human embryonic stem cells with an induced expression profile that more closely resembles native pluripotent cells and uninduced controls
Project description:Transcriptional profiling of Bacillus subtilis str 3610 cells comparing sinR-/epsH- cells to sinR-/epsH-/remA- cells in MSgg Medium at optical density (600nm) of 1.0
Project description:Identification of the specific WalR (YycF) binding regions on the B. subtilis chromosome during exponential and phosphate starvation growth phases. The data serves to extend the WalRK regulon in Bacillus subtilis and its role in cell wall metabolism, as well as implying a role in several other cellular processes.
Project description:Abstract of associated manuscript: Daptomycin is the first of a new class of cyclic lipopeptide antibiotics used against multidrug-resistant Gram-positive pathogens. The proposed mechanism of action involves disruption of the functional integrity of the bacterial membrane in a Ca2+-dependent manner. We have used transcriptional profiling to demonstrate that treatment of Bacillus subtilis with daptomycin strongly induces the lia operon including the autoregulatory LiaRS two-component system (homologous to Staphylococcus aureus VraSR). The lia operon protects against daptomycin and deletion of liaH, encoding a phage shock protein A (PspA)-like protein, leads to 3-fold increased susceptibility. Since daptomycin interacts with the membrane, we tested mutants with altered membrane composition for effects on susceptibility. Deletion mutations of mprF (lacking lysyl-phosphatidylglycerol) or des (lipid desaturase) increased daptomycin susceptibility, whereas overexpression of MprF decreased susceptibility. Conversely, depletion of the cell for the anionic lipid phosphatidylglycerol led to increased resistance. Fluorescently-labeled daptomycin localized to the septa and in a helical pattern around the cell envelope and was delocalized upon depletion of phosphatidylglycerol. Together, these results indicate that the daptomycin-Ca2+ complex interacts preferentially with regions enriched in anionic phospholipids and leads to membrane stresses that can be ameliorated by PspA family proteins.