Chlamydia pneumoniae is a small gram-negative bacterium that goes though transformations during its life cycle.

Life cycles of C. Pneumoniae (Chlamydia Pneumoniae or CPn) are:

  • Aberrant body (AB)
  • Elementary Body (EB)
  • Nucleus (N)
  • Reticulate Body (RB)

Elementary Body (EB)

Chlamydia Pneumoniae bacterium exists as Elementary Body between hosts. EB is not biologically active, but is resistant to environment. It is able to infect hosts by traveling from one person to another’s lungs by droplets.

Reticulate Body (RB)

When the bacterium has entered the host cell, it transforms into Reticulate Body. That is the form in which it replicates with help of host cell resources and metabolism. After replication it goes back into form of Elementary Body again.

Continuous transformation is one of the reasons why the disease is so tricky to control.