Effector proteins function to alter host cell physiology and promote bacterial survival in host tissues. This protein is required for endosomal tubulation and negatively regulates the formation of Salmonella-induced filaments (Sifs) in epithelial cells. Has both deacylase and esterification activities in vitro, but esterification is probably the dominant activity in host cells. Significantly contributes to cholesterol esterification, which reduces cellular cholesterol in cells and abrogates the ability of SifA to associate with cholesterol and LAMP-1 vesicles. Interacts with RhoA and indirectly with SifA. Secreted via type III secretion system 2 (SPI-2 TTSS), and delivered into the host cytoplasm. Localizes to the Salmonella-containing vacuole (SCV) at early time points following invasion and subsequently traffics away from the SCV along Salmonella-induced filaments (Sifs) in epithelial cells. Mutants have reduced cholesterol esterification activity as well as reduced lipid droplets. Belongs to the 'GDSL' lipolytic enzyme family.