Abstractis responsible for over 35% of all foodborne illness Salmonella typhimurium related hospitalizations in the United States. This Gram-negative bacterium possesses an inner and an outer membrane (OM), the latter allowing its survival and replication within host tissues. During infection, OM is remodeled by transport of glycerophospholipids across the periplasm and into the OM. Increased levels of cardiolipin in the OM were observed upon PhoPQ activation and led to the discovery of YejM; an inner membrane protein essential for cell growth involved in cardiolipin binding and transport to the OM. Another protein that might be playing a role in cardiolipin transport is YejL, as its gene is localized upstream of on the same operon. Here we report how yejm YejM was engineered to facilitate crystal growth and X-ray diffraction analysis. Furthermore, we present for the first time that YejL is a ligand for YejM. Successful structure determination of YejM and YejL will help us understand how they interact and how YejM facilitates cardiolipin transport to the OM. Ultimately, , being an essential gene, may lead to new drug targets yejm inhibiting the pathogenic properties of . S. typhimuriumSusanne Ressl ( )

Salmonella  typhimurium is responsible for over 35% of all foodborne illness related hospitalizations in the United States. This Gram-negative bacterium possesses an inner and an outer membrane (OM), the latter allowing its survival and replication within host tissues. During infection, OM is remodeled by transport of glycerophospholipids across the periplasm and into the OM. Increased levels of cardiolipin in the OM were observed upon PhoPQ activation and led to the discovery of YejM; an inner membrane protein essential for cell growth involved in cardiolipin binding and transport to the OM. Here we report how YejM was engineered to facilitate crystal growth and X-ray diffraction analysis. Successful structure determination of YejM will help us understand how they interact and how YejM facilitates cardiolipin transport to the OM. Ultimately, yejm, being an essential gene, may lead to new drug targets inhibiting the pathogenic properties of  S. typhimurium.