Abortive infection (Abi) systems can stop phage replication by forcing infected cells to arrest growth or die, but this strategy is risky if it is triggered in the absence of phage. Here, we show that two Hachiman-family Abi systems—AbpAB and HamAB—require Escherichia coli DNA polymerase I (PolA) to block phage growth. PolA is also required for AbpAB-dependent growth arrest triggered by DNA damage (mitomycin C) or by expression of the T4 single-stranded DNA-binding protein gp32. In contrast, deleting rnhA (encoding RNase HI) makes AbpAB expression toxic even in the absence of phage. These results show that host replication and repair enzymes can both support anti-phage defense and prevent Abi-associated growth inhibition during uninfected growth.

Bacteria deploy diverse immune systems to counter phage infection, yet how these systems sense invasion remains incompletely understood. This Review categorizes phage-derived triggers and outlines eme...

Nature Reviews Microbiology, Published online: 02 October 2026; doi:10.1038/s41579-026-01376-xBacteria deploy diverse immune systems to counter phage infection, yet how these systems sense invasion remains incompletely understood. This Review categorizes phage-derived triggers and outlines emerging principles that govern immune recognition of phage infection.

Cultured phage collections provide essential access to viral biology, but they capture only a small and biased fraction of natural phage diversity. Key barriers to diverse phage isolation are likely t...

Für wen eignet sich eine Phagentherapie?

CRISPR-Cas provides RNA-mediated adaptive immunity, but how its first RNA-guided effector arose is unclear. In this study, we report the discovery of Viral Interference Programmable Repeat (VIPR) syst...

The T7 bacteriophage deactivates bacterial defence systems through T7K phosphorylation of nearly all host and phage proteins during infection.

The T7 bacteriophage deactivates bacterial defence systems through T7K phosphorylation of nearly all host and phage proteins during infection.

Many important biological functions arise not from single genes but from complex interactions encoded by entire genomes. We report the first generative design of complete bacteriophage genomes using g...

DNA glycosylases, typically used for DNA repair, can also protect bacteria against phages that would otherwise evade host immunity by incorporating modified bases into their genomes.

Bacterial reverse transcriptases defend against viruses, yet how their DNA products stop infection remains unknown. Bacteriophage inhibition of a host recombination enzyme activates the DRT3 defense s...

Systematic analysis of prokaryotic STAND NTPases — relatives of animal and plant immune receptors — uncovers diverse antiviral sensors that detect most of the core structural and replicative proteins of bacteriophages.

Shomar, Guillaume, et al. report the genomics-driven discovery of a family of more than 2,000 lanthipeptide biosynthetic gene clusters with anti-phage potential. They experimentally demonstrate anti-p...

Bacterial defense systems provide a rich reservoir for biotechnological innovation. Retrons are tripartite abortive infection systems that detect phage invasion using reverse-transcribed DNA (msDNA), ...

Retrons are prokaryotic genetic elements that protect bacterial cells from invading phages. The type IX retron comprises a non-coding RNA, a reverse transcriptase (RT), and dual effectors: a putative ...

Gabija acts early during phage infection, preventing phage genome circularization and replication. Phage DNA end-binding proteins prevent RecBCD loading onto linear DNA, and the absence of RecBCD lice...

OLD, an abortive immunity protein from prophage P2, consists of an ABC ATPase sensor and a TO-PRIM nuclease effector - a core architecture shared by a large protein family, including components of ant...

Nature Microbiology, Published online: 26 June 2026; doi:10.1038/s41564-026-02407-2The END nuclease targets eight phage families with at least ten different known DNA modifications, but not unmodified DNA. Its specificity is dictated by the C-terminal iEndoIII domain. To combat END, modified phages encode direct-binding inhibitors.

Auxiliary metabolic genes, acquired by cyanobacterial viruses (cyanophages) from their hosts, are thought to manipulate host metabolism during infection. A recent study by Nadel et al. performed in vi...

Nature Microbiology, Published online: 12 June 2026; doi:10.1038/s41564-026-02384-6The activation of an antiphage defence system relies on host factors targeted by phages, a mechanism analogous to the way that eukaryotic innate immune systems detect pathogen-induced perturbations of host cells through effector-triggered immunity.

Bacteria and archaea possess an enormous variety of antiviral immune systems that often share homologous proteins and domains. YprA-family helicases a…

CRISPR-Cas adaptive immunity systems provide defense against mobile genetic elements and are often countered by diverse anti-CRISPR (Acr) proteins....

The life cycle of temperate bacteriophages involves lytic or lysogenic cycles and has historically served as a model for studying genetic regulation. This Review provides an updated overview of these ...

El Mouali and Tawk et al. characterize the oxygen-tolerance response in the human gut-residing bacterium Segatella copri. They identified a subset of strains that acquired an additional oxygen regulat...

Browser-based prophage prediction using PhiSpy, Pyodide, and WebAssembly

Because all known living organisms are made from at least 20 canonical amino acids, the feasibility of life using a more simplified alphabet remains unclear. In this work, we leveraged computational d...