Figure 3. Steady state ¹³C tracer analysis of the aa3 cytochrome oxidase mutant strain.

(A) Metabolic subnetwork that could be deciphered using steady state ¹³C tracer analysis. Pathways with dashed line indicate multiple reactions combined into one reaction. Labeling pattern of metabolites in bold are measured using LC-MS/MS. TCA cycle contributes 45% of total influx into malate de novo synthesis, similar to WT. (B) Labeling patterns of malate and threonine (reflecting OAA) of the aa3 mutant strain showing different carboxylation signature.