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Understanding antibiotic resistance
Understanding antibiotic resistance

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3 Exploiting the natural defences of bacteria

In Weeks 3 and 4, you saw how antibiotic resistance naturally evolved to protect bacteria as they compete for limited resources in the wild. But antibiotics are just one weapon in bacteria’s defence arsenal. Some bacteria prey on other microbes, attacking and killing them. These predatory bacteria could be exploited to kill infectious pathogens as another alternative to antibiotics.

The best known type of predatory bacteria is Bdellovibrio bacteriovorus (Figure 7).

A scanning electron micrograph of the comma-shaped Bdellovibrio.
Figure 7 The predatory bacterium Bdellovibrio bacteriovorus.

Bdellovibrio bacteriovorous attaches to the surface of its prey. Once attached, it penetrates the bacterial cell membrane and replicates. Finally, the prey bacterium is lysed, releasing new B. bacteriovorous particles into the environment (Figure 8).

A schematic of the life cycle of Bdellovibrio bacteriovorus.
Figure 8 The life cycle of Bdellovibrio bacteriovorus.