186
Chapter 5
Use P/0 = 2 in overall reaction 2 and show that the experimentally observed stoichiometry:
-CH20 + 0.543 P + 0.120 X + 0.337 C 02 - 0.150 0 2 = 0
is obtained by combining overall reactions (1) to (3) in the ratio 0.7714: 0.1738: 0.0548.
The maintenance demand is significant, but not alarming. There is probably a kinetic
bottleneck in the pathway v2 from glucose to 3 G which causes overflow to (useless)
biomass formation. This needs to be looked at as a part of the physiological design of the
final production strain.
The solution to this question is helpful in understanding the (mathematically) complex
methods of section 5.4.2.
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