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\section{Introduction}  \emph{Francisella tularensis} is Gram-negative bacterial pathogen capable of causing disease in a remarkably diverse collection of hosts; at least 190 different species of mammals, 23 birds, 3 amphibians and 88 invertebrates are recognized as susceptible to infection (Morner \cite{TuliBook}(Morner  and Addison, 2001). In addition, \textit{F. tularensis} utilizes a wide variety of environmental arthropod vectors for spread between hosts \cite{24057273, 21529386, 20482589, 18950590, 22530023, 21612530, 20885922}. In experimental animals, \emph{F. tularensis} invades and replicates within both phagocytic and non-phagocytic cells \cite{24427743, 23966861, 21687806, 23322778} and several studies have demonstrated that \emph{F. tularensis} survives engulfment by bacterivorous protists, often escaping from the food vacuole and replicating within the cytosol (Abd et al 2003; Lauriano et al 2004; PMC2786426\cite{19820161}). This ability to survive intracellularly is thought to contribute to the low infectious dose of \textit{F. tularensis}, which is fewer than 10 cells in some cases (refs). Due to this high infectivity and an accompanying high rate of mortality and morbidity, \emph{F. tularensis} is of particular concern as an agent of biological warfare and is therefore classified as a Tier 1 select agent by the US Centers for Disease Control (1, 2). An attenuated live vaccine strain (LVS) was created from a virulent isolate in the 1950s (3). [Sentence describing the attenuation]. In addition to its use as an IND human vaccine that is administered to patient populations at increased risk for tularemia (ref), the LVS strain allows for the study of \textit{F. tularensis} pathogenesis in biosafety level two laboratories (refs).