Control of bacterial transcription, translation and replication by (p)ppGpp.
The small nucleotides pppGpp and ppGpp (or (p)ppGpp) are rapidly synthesized in response to nutritional stress. In Escherichia coli, the enzymes RelA and SpoT are triggered by different starvation signals to produce (p)ppGpp. In many Gram-positive bacteria this is carried out by RelA and two small homologs. (p)ppGpp, along with the transcription factor DksA, has profound effects on transcription initiation in E. coli. (p)ppGpp/DksA exert differential effects on promoters by playing upon their intrinsic kinetic parameters, and by facilitating the utilization of alternative sigma factors. (p)ppGpp also regulates replication and translation. These studies highlight (p)ppGpp as a key factor in bacterial physiology that responds rapidly to diverse stresses, by shutting down growth and priming cellular defensive and adaptive processes.
Srivatsan
Anjana
A
Department of Molecular and Human Genetics, One Baylor Plaza, Room S-911, Mail Stop 225, Baylor College of Medicine, Houston, TX 77030, United States.
Wang
Jue D
JD
D001412:Bacillus subtilis / Q000235:genetics / Q000378:metabolism / Q000502:physiology*; D001426:Bacterial Proteins / Q000235:genetics / Q000378:metabolism*; D004926:Escherichia coli / Q000235:genetics / Q000378:metabolism / Q000502:physiology*; D015964:Gene Expression Regulation, Bacterial; D006159:Guanosine Tetraphosphate / Q000378:metabolism*; D014176:Protein Biosynthesis; D014158:Transcription, Genetic
D001426:Bacterial Proteins; D006159:Guanosine Tetraphosphate