Characterization of the metabolic shift between oxidative and fermentative growth in Saccharomyces cerevisiae by comparative 13C flux analysis

Table 2 Anabolic demand of Saccharomyces cerevisiae during aerobic glucose-limited chemostat culture at different dilution rates. The data are given in μmol (g cell dry mass)^-1 and are calculated from the cellular composition.

Compound	D = μ = 0.15 h^-1	D = μ = 0.30 h^-1	D = μ = 0.40 h^-1
Glucose 6-phosphate	2089	1694	1431
Erythrose 4-phosphate	243	281	307
Ribose 5-phosphate	115	127	141
Glyceraldehyde 3-phosphate	77	77	77
Phosphoglycerate (for lipids, nucleotides)	44	44	44
Phosphoglycerate (for serine + cysteine)	343	397	433
Phosphoglycerate/Oxaloacetate (for glycine)^a	236	273	298
Oxaloacetate (for threonine, methionine, isoleucine)	393	455	496
Oxaloacetate (for others)	290	332	364
Phosphoenolpyruvate	457	529	577
Pyruvate (for alanine)^b	304	352	384
Pyruvate (mitochondrial, for others)	981	1135	1237
Acetyl-CoA (cytosolic)	2108	2142	2164
Acetyl-CoA (mitochondrial)	216	250	273
2-Oxoglutarate	1008	1166	1272
NADPH	10088	11206	11956

^a The actual precursor demand for glycine biosynthesis depends on the contribution of the serine pathway (from phosphoglycerate) and threonine aldolase (from oxaloacetate). Based on the relative activity of both pathways, the corresponding demand has to be added appropriately to phosphoglycerate and oxaloacetate, respectively.
^b The demand of cytosolic and mitochondrial pyruvate for alanine synthesis depends on the relative contribution of cytosolic and mitochondrial route to alanine synthesis.

ISSN: 1475-2859