A unique feature of the intracellular life cycle ofLegionellapneumophilais the interaction between the vacuole in whichL. pneumophilaresides and the endoplasmic reticulum of the host cell. This interaction is crucial forL. pneumophilato establish a niche in which the bacteria can replicate intracellularly. Microscopic analysis of endoplasmic reticulum (ER) markers during infection yields information regarding the nature of the recruited vesicles as well as the kinetics of their recruitment. The recruitment of YFP-KDEL, GFP-p58, calnexin, and myc-Sec22b to theL. pneumophila– containing vacuole can be assessed by fluorescence microscopy. Methods for detection of these various ER markers during infection of mammalian cells byL. pneumophilaare described.
