Dear Editor,Legionella pneumophila,a gram-negative bacterium,is the causative agent of Legionnaires pneumonia by infecting human lung macrophages (Muder et al.,1986).Upon uptake into macrophages,the bacteria are intealized to escape the endocytic pathway and lysosomal network,and establish the Legionellacontaining vacuole (LCV) as an intracellular replicative organelle (Roy et al.,1998).The LCV hijacks and recruits theearly secretory ER-derived vesicles and transforms them into ER-like vacuole.