Changes

These bacteria only grow in the presence of living eukaryotic cells as they are unable to synthesise ATP therefore requiring intermediates from host cells. There are two morphological forms:

These bacteria only grow in the presence of living eukaryotic cells as they are unable to synthesise ATP therefore requiring intermediates from host cells. There are two morphological forms:

*Elementary body, the infective extracellular form, which is small, metabolically inert and osmotically stable; surrounded by cytoplasmic membrane, outer membrane with LPS, but no peptidoglycan

*Elementary body, the infective extracellular form, which is small, metabolically inert and osmotically stable; surrounded by cytoplasmic membrane, outer membrane with LPS, but no peptidoglycan

*Retiuculate body: larger, metabolically active, osmotically fragile

*Reticulate body: larger, metabolically active, osmotically fragile

The elementary body survives in the environment for several days.

The elementary body survives in the environment for several days.

==Pathogenesis and Pathogenicity==

==Pathogenesis and Pathogenicity==