Pleomorphism refers to the ability of an organism to alter its morphology and reproductive and other metabolic behavior in response to environmental changes.
The genera Corynebacterium and Coccobacillus are referred to as pleomorphic bacteria.
Some of the bacteria belonging to the Deinococcaceae family show pleomorphism.
Example: Deinococcus radiodurans is an extremophile and is the most radiation-resistant bacterium known.
Legionella pneumophila is another example of pleomorphic bacteria. Helicobacter pylori also show pleomorphism.