Open AccessThe Salmonella ‐containing vacuole is a major site of intracellular cholesterol accumulation and recruits the GPI‐anchored protein CD55
Author(s) -
Catron Drew M.,
Sylvester Matthew D.,
Lange Yvonne,
Kadekoppala Madhusudan,
Jones Bradley D.,
Monack Denise M.,
Falkow Stanley,
Haldar Kasturi
Publication year - 2002
Publication title -
cellular microbiology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.542
H-Index - 138
eISSN - 1462-5822
pISSN - 1462-5814
DOI - 10.1046/j.1462-5822.2002.00198.x
Subject(s) - vacuole , intracellular , biology , endosome , endocytic cycle , intracellular parasite , microbiology and biotechnology , salmonella , bacteria , biochemistry , endocytosis , cell , cytoplasm , genetics
Summary Intracellular, pathogenic Salmonella typhimurium avoids phago‐lysosome fusion, and exists within a unique vacuolar niche that resembles a late endosome. This model has emerged from studying the trafficking of host proteins to the Salmonella ‐containing vacuole (SCV). Very little is known about the role of major host lipids during infection. Here, we show using biochemical analyses as well as fluorescence microscopy, that intracellular infection perturbs the host sterol biosynthetic pathway and induces cholesterol accumulation in the SCV. Cholesterol accumulation is seen in both macrophages and epithelial cells: at the terminal stages of infection, as much as 30% of the total cellular cholesterol resides in the SCV. We find that accumulation of cholesterol in the SCV is linked to intracellular bacterial replication and may be dependent on Salmonella pathogenicity island 2 (SPI‐2). Furthermore, the construction of a three‐dimensional space‐filling model yields novel insights into the structure of the SCV: bacteria embedded in cholesterol‐rich membranes. Finally, we show that the glycosylphosphatidylinositol (GPI)‐anchored protein CD55 is recruited to the SCV. These data suggest that, in contrast to prevailing models, the SCV accumulates components of cholesterol‐rich early endocytic pathways during intracellular bacterial replication.