FIG 2.

Glutamine is an essential anaplerotic substrate for the TCA cycle during VACV infection. (A) Simplified schematic of glucose and glutamine utilization. The dashed arrow represents multiple enzymatic reactions within the metabolic pathway. Abbreviations: alpha-KG, α-ketoglutarate; OAA, oxaloacetic acid; ACoA, acetyl coenzyme A. (B and C) HFFs were infected with VACV at an MOI of 5 and were fed replete medium, glutamine-free medium, or glutamine-free medium supplemented with 7 mM dimethyl-α-ketoglutarate, 4 mM oxaloacetic acid, or 4 mM pyruvate (B) or fed replete medium with 0 μM BPTES, 10 μM BPTES, or 10 μM BPTES and 7 mM dimethyl-α-ketoglutarate (C) at 1 hpi. Cell-associated virus was collected at 24 hpi, and viral yields were determined by a plaque assay.