Table 2.

Isotope labeling measurements used for metabolic flux determination.

Metabolite	Mass	Carbons	Composition
3PGA	585	123	C23 H54 O7 Si4 P
SER	390	123	C17 H40 O3 N Si3
PEP	453	123	C17 H38 O6 Si3 P
PYR	174	123	C6 H12 O3 N Si
ALA	232	23	C11 H26 O2 N Si2
LAC	233	23	C10 H25 O2 Si2
CIT	465	123456	C20 H39 O6 Si3
SUC	289	1234	C12 H25 O4 Si2
FUM	287	1234	C12 H23 O4 Si2
MAL	419	1234	C18 H39 O5 Si3

Abbreviations: 3PGA, 3-phosphoglycerate; ALA, alanine; CIT, citrate; FUM, fumarate; LAC, lactate; MAL, malate; SER, serine; PEP, phosphoenolpyruvate; PYR, pyruvate; SUC, succinate. Measurements taken at t = 0, 1, 2, 5, 10, and 20 min were fitted to the INST-MFA model. Note that the MID of 3PGA could not be accurately quantified in the SA590-PK (−thiamin) experiment.