Project description:Transcriptional profiling of Bacillus subtilis to lethal heat stress by systematic sampling of bacterial cell suspensions exposed to gradually increasing temperatures. Keywords: Stress response
Project description:Bacterial cells often modulate their transcriptional profiles in response to the changes in iron availability. Ferric uptake regulator (Fur), as a global iron biosensor, plays a central role in maintaining iron homeostasis in Bacillus subtilis. Here we utilized a high affinity Fe2+ efflux transporter, Listeria monocytogenes FrvA, as an inducible genetic tool to deplete intracellular iron. We then characterized the responses of the Fur, FsrA, and PerR regulons as cells transition from iron sufficiency to deficiency. Our results indicate that the Fur regulon is derepressed in three distinct waves. First, elemental iron uptake (ywbLMN), ferric citrate uptake (ymfCDEF-yhfQ), and petrobactin uptake (yclNOPQ) systems are induced to prevent iron deficiency. Second, B. subtilis synthesizes its own siderophore bacillibactin (dhbACEBF) and turns on bacillibactin uptake (feuABC-yusV) along with flavodoxin (ykuNOP) and hydroxamate siderophore uptake (fhuBCGD-yxeB) to scavenge iron from the environment. Third, as iron levels decline further, an iron sparing response (fsrA, fbpAB, and fbpC) is induced to block the translation of nonessential iron-using proteins and permit only essential iron-dependent enzymes to utilize the limited iron. ChIP experiments demonstrate that in vivo occupancy of Fur correlates with derepression of each operon, and the graded response observed here results, at least in part, from higher affinity binding of Fur to the late induced genes. These results provide insights into the distinct roles of Fur-regulated target genes as intracellular iron levels decline.
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:Transcriptional response of Bacillus subtilis to moenomycin in wild-type 168. Bacillus subtilis 168, WT (-MOE) vs. WT (+MOE). The experiment was conducted in triplicate using three independent total RNA preparations. Untreated samples were labeled with Alexa Fluor 555 and moenomycin treated samples were labeled with Alexa Fluor 647.
Project description:Transcriptional response of Bacillus subtilis to ramoplanin in wild-type CU1065. Bacillus subtilis CU1065, WT (-RAM) vs. (+RAM) and liaR (yvqC) deletion (-RAM) vs. (+RAM). The experiment was conducted in triplicate using three independent total RNA preparations. Combined reference RNA was labeled with Cy3 and ramoplanin treated/untreated samples were labeled with Cy5.
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.
