Regulation of the stringent response is the essential function of the conserved bacterial G protein CgtA in Vibrio cholerae

摘要: The gene encoding the conserved bacterial G protein CgtA (Obg) is essential for viability in every organism which it has been studied. reported to be involved several diverse functions, including ribosome assembly, DNA repair, sporulation, and morphological development. However, none of these functions have identified as essential. Here we show that depletion Vibrio cholerae causes global changes expression are consistent with induction a classical low nutrient stress response or “stringent” response. We leads increased ppGpp levels correlate cessation growth. enzyme RelA responsible synthesis alarmone during stringent no longer relA deletion mutant thus conclude essentiality directly linked its ability affect levels. SpoT degrades ppGpp, here RelA+ CgtA+ background but not mutant. also confirmed interacts two-hybrid assay. suggest function repressor acts by regulating activity maintain when bacteria growing nutrient-rich environment.