PknG senses amino acid availability to control metabolism and virulence of Mycobacterium tuberculosis
Fig 6
GarA was required during stationary phase for the maintenance of intracellular glutamate and for survival.
(A) M. smegmatis lacking garA failed to maintain intracellular glutamate and glutamine pools during extended stationary phase in 7H9 medium. Intracellular glutamate and glutamine were measured for wild type M. smegmatis (black circles), ΔgarAMs (red squares), and complemented ΔgarAMs (black triangles). Inset graphs show intracellular metabolites for the same experiment at day 28 (B) M. smegmatis lacking garA gradually lost viability during prolonged stationary phase. Cells were cultured in 7H9 medium over a time period of five months. Aliquots were withdrawn at regular intervals and surviving cells were plated on 7H10 to calculate CFU ml-1. All experiments were repeated at least 3 times and data show the mean with standard deviation.