Proliferation of lytic phages largely relies on the successful exploitation of bacterial replication, transcription and translation machineries. Hence, bacteriophages need to outwit bacterial defense and stress response systems to achieve their reproduction. Since the phages rapidly exploit the energetic and metabolic resources of their host cells to achieve their multiplication, we wondered if the general bacterial stress sensing and metabolic control system – the stringent response (SR) – might interfere with phage replication. The stringent response is a bacterial stress sensing and signaling mechanism that relies on the nucleotide second messengers (p)ppGpp. They are produced (e.g.) in response to amino acid starvation and essentially control all levels of the bacterial metabolism and physiology. This project will unravel the interplay and regulatory mechanisms between bacterial (p)ppGpp-related stress signaling and potential modulations delivered by the attacking phages. The interdisciplinary project combines basic microbiology, biochemistry and structural analysis.