Comprehensive Transcriptional Profiling of the Cell Envelope Stress Response of Bacillus subtilis

Bacterial cell envelope is the first and the major line of defense against threats from the environment. Because of its crucial roles in bacterial cell life, cell envelope is a prime target for numerous antibiotics. In this study, by treating Gram-positive model strain Bacillus subtilis with numbers of cell wall targeted antibiotics, we aimed to obtain a global comprehensive transcriptional profile of cell envelope stress response in B. subtilis via transcriptomic study using high-throughput RNA sequencing approach. This knowledge will then be subject to a series of comparative genomics analyses to get detailed information of the distribution and conservation of cell envelope stress-sensing regulatory systems in B. subtilis. Wild type Bacillus subtilis W168 cells at exponential phase of growth were treated with cell wall-targeted compounds, bacitracin, vancomycin, tunicamycin, phophomycin, penicillin G, flavomycin and lysozyme, respectively. With 10 min of induction, all samples were processed to undergo total RNA extraction, cDNA library preparation and then high-throughput RNA sequencing. The resulting sequencing raw data were analyzed in silico to reveal the differential gene expression in different treatments relative to non-treatment control.