Elucidation of intrinsic biosynthesis yields using 13C-based metabolism analysis

Table 1 Simplified biochemical reactions considered in the model

Flux, v	Reactions	Note
v(1)	Glucose ➔ 2AceCoA + 2ATP + 4NADH	Glycolysis
v(2)	AceCoA + 1.75NADPH + 0.875ATP ➔ 0.125 C16:0 fatty acid	Fatty acid synthesis
v(3)	AceCoA ➔ 2NADH + NADPH + ATP + FADH2	TCA cycle
v(4)	NADH ➔ NADPH	Transhydrogenation
v(5)	NADH ➔ P/O ATP	Oxidative phosphorylation
v(6)	FADH2 ➔ 0.67(P/O)ATP	Oxidative phosphorylation
v(7)	ATP ➔ ATP_maintenance	ATP maintenance (non-growth associated)
v(8)	6.6Glucose + 37.6ATP + 9.5NADPH + 2.5AceCoA ➔ 39.7Biomass + 3.1NADH	Biomass formation

Note: Glucose consumption for both biomass growth and product synthesis is normalized to 100. The linear optimizer ‘linprog’ function in MATLAB is used for the optimization. The final yield (g fatty acid/g glucose) is calculated as follows: Y = (v(2)/8∙256)/(100∙180) g C16:0 fatty acid/g glucose.

ISSN: 1475-2859