1: J Infect Dis. 2009 Nov 1;200(9):1367-70.

Role of rsbU and Staphyloxanthin in Phagocytosis and Intracellular Growth of
Staphylococcus aureus in Human Macrophages and Endothelial Cells.

Olivier AC, Lemaire S, Van Bambeke F, Tulkens PM, Oldfield E.

Unité de pharmacologie cellulaire et moléculaire and Louvain Drug Research
Institute, Université catholique de Louvain, Brussels, Belgium; 2Department of
Chemistry and Center for Biophysics and Computational Biology, University of
Illinois, Urbana, IL.

In Staphylococcus aureus, rsbU down-regulates agr and stimulates production of
staphyloxanthin (STX), an antioxidant that may contribute to intracellular
survival after phagocytosis. Using isogenic rsbU(-) and rsbU(+) strains, we show 
that rsbU causes increased internalization and intracellular growth in both THP-1
macrophages and human umbilical vein endothelial cells (more so for the latter)
without change in subcellular localization and that inhibition of STX
biosynthesis markedly reduces intracellular growth of the rsbU(+) strain (and of 
clinical isolates, including USA300; tested with macrophages only) without
affecting internalization. Thus, rsbU is important for uptake and for STX
biosynthesis and is critical for intracellular multiplication of S. aureus.

PMCID: PMC2762113 [Available on 2009/11/01]
PMID: 19817587 [PubMed - in process]

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