meRfi®-GM
The Digital Textbook on Gut Microbiota and Beyond

p-ppGpp stands for guanosine tetraphosphate (ppGpp) and guanosine pentaphosphate (pppGpp). When bacteria detect danger - like starvation or other stress - they quickly produce large amounts of p-ppGpp. This acts as an emergency signal to help the cell survive tough conditions by rapidly changing its internal processes
Pacios et al. 2020 Antimicrob Agents Chemother 64:1
Fernández-Coll & Cashel 2020 Front Microbiol 11: 592718

When danger (such as nutrient shortage) is sensed:

• The cell slows down growth.


• Ribosome production, protein synthesis, DNA replication, and energy usage are reduced or reprogrammed.


• Resources are shifted away from growth and towards survival, repair, and str…