The General Stress Response in Gram-Negative Bacteria

摘要: Being exposed to various kinds of stress in their natural environments, bacteria usually grow slowly or even have use limited resources entirely for maintenance and survival. The latter requires the induction general response, which, Escherichia coli related gram-negative bacteria, depends on σS (RpoS) subunit RNA polymerase. is closely vegetative sigma factor σ70 (RpoD) these two factors recognize similar but not identical promoter sequences. Target gene products a variety stress-protective functions that redirect metabolism, affect cell envelope shape, are involved biofilm formation pathogenesis, increase stationary phase stress-induced mutagenesis. This chapter summarizes diverse amazingly complex regulation σS. At molecular level, processes integrated with partitioning global transcription space by competition polymerase (RNAP) core enzyme signaling nucleotide second messengers include cAMP, (p)ppGpp, c-di-GMP. Physiologically, key player balance between lifestyle associated slow growth based nutrient scavenging motility focused strong resistance can sedentary multicellular existence biofilm. primary requirement inducing response E. accumulation, expression patterns many σS-dependent genes then being fine-tuned additional signal input.