Which bacterium attacks and digests other bacteria from inside their cells?

Bdellovibrio bacteriovorus attacks and digests other bacteria from inside their cells.

This predatory bacterium swims rapidly through water and attaches to a suitable Gram-negative bacterial prey cell. It then enters the periplasm, the space between the prey’s inner and outer membranes, while reshaping the host into a structure called a bdelloplast.

Inside the bdelloplast, Bdellovibrio consumes the prey’s cellular contents and grows. It eventually divides into several offspring, which escape to hunt again. This unusual life cycle distinguishes it from bacteria that merely secrete toxins or compete for nutrients.

Researchers study Bdellovibrio as a possible source of new antibacterial strategies. It is not a general-purpose human antibiotic, and its activity is limited by prey type and environmental conditions.