Pleomorphism (microbiology)

In microbiology, pleomorphism (from Ancient Greek πλέω-, pléō, "more", and -μορφή, morphḗ, form), also pleiomorphism, is the ability of some microorganisms to alter their morphology, biological functions or reproductive modes in response to environmental conditions.

[1] The modern definition of pleomorphism in the context of bacteriology is based on variation of morphology or functional methods of the individual cell, rather than a heritable change of these characters as previously believed.

[1] In the first decades of the 20th century, the term "pleomorphism" was used to refer to the idea that bacteria change morphology, biological systems, or reproductive methods dramatically according to environmental cues.

[7] Legionella pneumophila, the species of intracellular bacteria parasite responsible for Legionnaire's disease, has been seen to differentiate within a developmentally diverse network.

[11] Additionally, in one study focused on agents involved in a non-infectious disease, pleomorphic bacteria were found to exist in the blood of healthy human subjects.