¹³C Metabolic Flux Analysis of Acetate Conversion to Lipids by Yarrowia lipolytica

Liu, N.; Qiao, K.; Stephanopoulos, G.

To better understand the metabolism of yeast Yarrowia lipolyticain the presence of volatile fatty acids, Stephanopoulos and colleagues performed a stationary ¹³C metabolic flux analysis using two isotopically labeled acetate tracers (¹³C and ¹³C₂) as the feedstock. Distribution maps were constructed from empirical (by GC- and LC-MS) and theoretical observations of two different yeast extracts: MTYL037 (served as the control) and MTYL065 (engineered lipid overproducer). Lipid synthesis pathways investigated during the growth and production phases included the TCA, glyoxylate shunt, gluconeogenesis, and pentose phosphate. The results indicated a flux dependence on strain and phase, with malate transport and pyruvate kinase playing critical roles in energy production.