SMPD1 and infection: Here, we demonstrate that ASM activity is essential for optimal infection cycle progression of four obligate intracellular vacuole-adapted bacterial pathogens that target host cholesterol trafficking pathways: Anaplasma phagocytophilum (Xiong et al, 2009; Xiong & Rikihisa, 2012), Coxiella burnetii (Howe & Heinzen, 2006; Mulye et al, 2018), Chlamydia trachomatis (Carabeo et al, 2003; Beatty, 2006, 2008; Kumar et al, 2006; Cocchiaro et al, 2008; Cox et al, 2012), and Chlamydia pneumoniae (Liu et al, 2010).