Chlamydia cell biology and pathogenesis

Chlamydiaspp. are intracellular bacteria that depend on the host for their metabolic requirements, while hiding from host immune defences. In this Review, Elwell, Mirrashidi and Engel detail the molecular mechanisms that enable these pathogens to shape and thrive in their niche in host cells. Chlamydia spp. are important causes of human disease for which no effective vaccine exists. These obligate intracellular pathogens replicate in a specialized membrane compartment and use a large arsenal of secreted effectors to survive in the hostile intracellular environment of the host. In this Review, we summarize the progress in decoding the interactions between Chlamydia spp. and their hosts that has been made possible by recent technological advances in chlamydial proteomics and genetics. The field is now poised to decipher the molecular mechanisms that underlie the intimate interactions between Chlamydia spp. and their hosts, which will open up many exciting avenues of research for these medically important pathogens.