HIV infection regulates the metabolism of latently infected macrophages. (A) Diagram of mitochondrial fuel input from glycolytic, glutamine, and fatty acid pathways, with appropriate inhibitors used to prevent the usage of these pathways. (B) OCR changes used to measure percentage dependency of one or two fuel types. OCR changes are measured at baseline (no compounds) for roughly 17 minutes, followed by injection of one fuel inhibitor for single fuel dependency, or with two inhibitors for double fuel dependency. OCR changes resulting from treatment are measured for approximately 40 minutes, followed by injection of the remaining two fuels for single fuel dependency experiments, or the single remaining fuel for double dependency measurements. Dependency for single and double fuel experiments is calculated as the percentage change from baseline due to the first injection. (B) Mitochondrial OXPHOS dependency on fatty acid, glutamine, and glucose. HIV infected macrophages were more dependent on glutamine than their uninfected counterparts (*p = 0.0001, n = 4). There was no significant change in dependency on fatty acid or glucose for OXPHOS during HIV infection. There was a significant dependence on fatty acids for OXPHOS in uninfected and HIV infected cells compared to glutamine and glucose (#p ≤ 0.0119). (C) Analysis of mitochondrial dependence on two fuel types for OXPHOS. When forced to use a single fuel source for OXPHOS, there was a significant decrease in the ability for HIV macrophages to use fatty acids and glucose, and a significant increase in the ability to use glutamine (*p ≤ 0.0002). Single and double dependency experiments indicate that uninfected macrophages are flexible to shift among several types of energy sources. However, HIV infected macrophages have an increased “flexibility” to shift among these forms of energy. (D) To evaluate whether the use of glutamine, glutamate, and α-KG is necessary for the survival of HIV reservoirs, we treated uninfected and HIV infected cultures of surviving macrophages with BPTES or Benzylserine. Both inhibitors did not alter the survival of uninfected cultures. However, the combination of both or Benzylserine alone resulted in significant cell death in the HIV infected cells. All points are significant after two days post-treatment (n = 4, p ≤ 0.005).