# GATE2014-49

Lysine is being produced in a lab-scale reactor by a threonine auxotroph. After 2 weeks of operation it was observed that the concentration of lysine in the reactor was gradually decreasing.Microbiological assays of reactor samples showed absence of contamination and recorded data showed no change in the operating conditions. The most probable reason for decrease in lysine concentration may be attributed to

1. accumulation of ethanol
2. growth of revertants
3. production of citric acid
4. unutilized phosphoenol pyruvate
in Others
edited

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