Non‑living bacteria continue weaving DNA, paving the way for engineered biomaterials

A team from Aarhus University demonstrated that bacterial cells keep producing DNA after they can no longer divide, a behavior they label “zombie bacteria.” This discovery challenges the traditional belief that DNA replication stops as soon as a cell dies.

In the lab, the researchers exposed typical bacterial strains to lethal compounds and tracked the subsequent intracellular activity. Fluorescent tags that attach to freshly synthesized nucleic acids revealed a surge of DNA production lasting several hours after conventional viability tests had verified cell death. Their results show that the enzymes responsible for polymerizing nucleotides stay functional even when the cell’s broader metabolism has ceased.

Importantly, the investigators found a way to dictate which genetic sequences the dead cells generate. Providing synthetic DNA templates together with the bacterial cultures enabled the zombie bacteria to construct specific strands of genetic material. Such precision indicates that deceased microbes might serve as miniature, self‑sufficient factories for bespoke nucleic‑acid products, eliminating concerns about uncontrolled proliferation.

The ramifications reach beyond fundamental microbiology. Should the technique be scaled up, it could facilitate the production of innovative biomaterials—like programmable hydrogels or biodegradable scaffolds—constructed from within by these inert yet chemically active cells. Since no living organisms are required, the method may bypass numerous regulatory and safety obstacles tied to genetically engineered microbes.

Although the work remains preliminary, the authors warn that additional research is required to delineate the boundaries of post‑mortem DNA synthesis and to avert accidental environmental release. Upcoming investigations are expected to test a wider array of bacterial species, evaluate the durability of the synthesized DNA, and examine ways to merge the approach with current synthetic‑biology workflows. If it proves viable, the “zombie bacteria” system could become another addition to the expanding suite of bio‑fabrication tools.