Systems-level metabolic flux profiling identifies fatty acid synthesis as a target for antiviral therapy

Abstract

Viruses rely on the metabolic network of their cellular hosts to provide energy and building blocks for viral replication. We developed a flux measurement approach based on liquid chromatography-tandem mass spectrometry to quantify changes in metabolic activity induced by human cytomegalovirus (HCMV). This approach reliably elucidated fluxes in cultured mammalian cells by monitoring metabolome labeling kinetics after feeding cells 13 C-labeled forms of glucose and glutamine. Infection with HCMV markedly upregulated flux through much of the central carbon metabolism, including glycolysis. Particularly notable increases occurred in flux through the tricarboxylic acid cycle and its efflux to the fatty acid biosynthesis pathway. Pharmacological inhibition of fatty acid biosynthesis suppressed the replication of both HCMV and influenza A, another enveloped virus. These results show that fatty acid synthesis is essential for the replication of two divergent enveloped viruses and that systems-level metabolic flux profiling can identify metabolic targets for antiviral therapy.The capability of mass spectrometry and nuclear magnetic resonance spectroscopy to quantify numerous metabolites simultaneously has given rise to the systems-level examination of metabolites (metabolomics) and their fluxes (fluxomics) [1][2][3] . Initial efforts to apply metabolomics to investigate human disease have focused largely on analysis of biofluids in normal versus affected individuals 4-7 . Although promising, such analysis is complicated by variation between individuals 8 . Moreover, the complexity of metabolic

Human kinome profiling identifies a requirement for AMP-activated protein kinase during human cytomegalovirus infection

“…HCMV induces glycolysis (8)(9)(10) and also causes increased levels of the glucose transporter GLUT4 at the plasma membrane increasing glucose uptake (11).…”

Erk regulation of pyruvate dehydrogenase flux through PDK4 modulates cell proliferation

“…Thus, system-level analyses are required to understand the complex regulation of glycolysis, the TCA cycle, and PDH flux by mitogenic, oncogenic, and environmental factors. 13 C metabolic flux analysis (MFA) provides an effective means of quantifying metabolic pathway utilization in mammalian cells (Boros et al 2003;Munger et al 2008;Zamboni 2011). The use of isotopic tracers, system-level data acquisition, and computational modeling allows for the estimation of fluxes and associated confidence intervals, which are the most representative characterization of in vivo enzyme function (Antoniewicz et al 2006;Metallo et al 2009).…”

Recent advances in CMV tropism, latency, and diagnosis during aging

“…The flow of carbons from glucose to fatty acid metabolism is increased, possibly involving the non-enzymatic conversation of a pyruvate to acetate to generate the substrates required for fatty acid synthesis and elongation (Vysochan et al 2017). Likewise, carbons from glutamine are redirected for anaplerotic usage to replenish the TCA cycle (Munger et al 2008;Chambers et al 2010). HCMV infection in human fibroblast dramatically increases the elongation of fatty acids to generate very long chain fatty acid tails (VLCFAs) (Koyuncu et al 2013;Purdy et al 2015).…”