Purification of infectious and non-infectious chlamydial particles using iodixanol for density gradient preparation.

Chlamydiae are obligate intracellular bacteria with two distinct morphological stages, the infectious elementary bodies (EBs) and non-infectious reticulate bodies (RBs). Here we describe a rapid and straightforward protocol for the purification of EBs and RBs involving special density gradients. It has been successfully applied to three chlamydial species.