Global Transcriptomic Profiling Reveals Conserved and Phage-specific Responses to Phage Infection in Escherichia Coli.

Although phages shape bacterial evolution and physiology, the specificity of host transcriptomic responses to phage infection remains incompletely understood. Here, we performed global transcriptomic profiling of Escherichia coli exposed to two lytic phages, ΦX174 and T4, and the temperate phage λ, to explore both conserved and phage-specific host responses. All infections induced stress-related genes, including SOS and general stress pathways, along with repression of anabolic processes such as purine and amino acid biosynthesis, suggesting a metabolic shift to conserve resources. Notably, ΦX174 strongly activated the phage shock protein operon, while both ΦX174 and λ selectively induced soxS, a regulator of oxidative stress. Despite infecting the same host, each phage triggered distinct transcriptional signatures. These findings highlight the complexity of bacterial responses and the value of transcriptomics in decoding host-phage interactions, offering insights into resistance, survival, and co-evolution.