FBP1 and infection: This is supported by the findings by Radlinski et al. (45) demonstrating that while F. tularensis is adept at modulating its metabolism to fluctuating concentrations of host-derived nutrients, the enzymes fructose 1,6-bisphosphatase (GlpX) and glycerol 3-phosphate dehydrogenase (GlpA) are essential for F. tularensis intracellular replication regardless of the infection models tested.