Upon entry of Legionella pneumophila into amoebas and macrophages, host-mediated 
farnesylation of the AnkB effector enables its anchoring to the 
Legionella-containing vacuole (LCV) membrane. On the LCV, AnkB triggers docking 
of K(48)-linked polyubiquitinated proteins that are degraded by the host 
proteasomes to elevate cellular levels of amino acids needed for intracellular 
proliferation. Interference with AnkB function triggers L. pneumophila to 
exhibit a starvation response and differentiate into the nonreplicative phase in 
response to the basal levels of cellular amino acids that are not sufficient to 
power intracellular proliferation of L. pneumophila. Therefore, we have 
determined whether the biological function of AnkB is temporally and spatially 
triggered upon bacterial attachment to the host cell to circumvent a 
counterproductive bacterial differentiation into the nonreplicative phase upon 
bacterial entry. Here, we show that upon attachment of L. pneumophila to human 
monocyte-derived macrophages (hMDMs), the host farnesylation and ubiquitination 
machineries are recruited by the Dot/Icm system to the plasma membrane 
exclusively beneath sites of bacterial attachment. Transcription and injection 
of ankB is triggered by attached extracellular bacteria followed by rapid 
farnesylation and anchoring of AnkB to the cytosolic side of the plasma membrane 
beneath bacterial attachment, where K(48)-linked polyubiquitinated proteins are 
assembled and degraded by the proteasomes, leading to a rapid rise in the 
cellular levels of amino acids. Our data represent a novel strategy by an 
intracellular pathogen that triggers rapid nutritional remodeling of the host 
cell upon attachment to the plasma membrane, and as a result, a gratuitous 
surplus of cellular amino acids is generated to support proliferation of the 
incoming pathogen.