Cross Index Chlamydia
SuperSet Prokaryote, Eubacteria
Compare Rickkettsiaceae: Cowdria, Coxiella, Erhlichia, Neorickettsia, Rickettsia, Rickettsiella, Rochalimaea Wobachia
Bartonellaceae: Bartonella, Grahamella
Anaplasmatacae: Aegyptianella, Anaplasma, Eperythrozoan, Haemobartonella


Contrast Archaea


Morphology Chlamydia
Staining Gram-negative. Cell walls are similar in structure and composition to walls of other Gram-negative bacteria, but muramic acid is either absent or is present only in traces. There is a genus-specific, wall-associated, lipopolysaccharide antigen that contains a 2-keto-3-deoxyoctanoic acid-like substance
Morphology coccoid organisms, 0.2-1.5 um, Transition between elementary bodies and reticulate bodies is gradual, and intermediate forms exist. Elementary bodies are 0.2-0.4 um in diameter. They contain electron-dense nuclear material and few ribosomes, are surrounded by rigid trilaminar walls, and are infectious. Reticulate bodies are 0.6-1.5 um in diameter. As compared to elementary bodies, reticulate bodies have less dense, fibrillar nuclear material, more ribosomes, and thinner and more flexible trilaminar walls. Infectivity of reticulate bodies for new host cells has not been demonstrated.
Motility Non-motile
Specialized structures Walls of elementary and reticulate bodies exhibit regular hexagonal arrays of subunits on the inner surface and single patches of hexagonally ordered hemispheric projections on their outer ones
Division multiplying only within membrane-bounded vacuoles in the cytoplasm of host cells by means of a unique developmental cycle characterized by change of small elementary bodies into larger reticulate bodies that divide by fission. The cycle is complete when reticulate bodies reorganize and condense into a new generation of elementary bodies which survive extracellularly
Solid surface  


Growth Parameters Chlamydia
Tropism Chlamydiae rely on their hosts for high-energy compounds and low molecular weight synthetic intermediates which they use to synthesize their own DNA, RNA and protein, as well as smaller molecules specific for chlamydiae and not made by host cells
Requirements Multiplication of chlamydiae outside of host cells has not been achieved. They may be propagated in laboratory animals, yolk sacs of chicken embryos or in cell cultures
Unique features  
Pathogenicity Chlamydiae cause a variety of diseases in humans, other mammals, and birds. infect other host cells by an unusual phagocytic mechanism that does not involve fusion of chlamydia- containing phagosomes with lysosomes


Genome Chlamydia
G+C Mol % 41-44 (Tm)
  The genome size is among the smallest of all procaryotes, 4-6 x 108 daltons


Reference Chlamydia
First citation Rake,G. 1957 Family Chlamydiaceae fam. nov.. In Breed, Murray and Smith (Editors) Bergey's Manual of Determinative Bacteriology, 7th Ed. The Williams and Wilkins Co. Baltimore, pp 957-968
The Prokaryotes  
Bergey's Systematatic p 729 J. W. Moulder, T.P. Hatch, C-C. Kuo, J. Schachter and J. Storz