Metabolic Engineering for Cadaverine Production

As mentioned earlier, the cadaverine pathway in E. coli is hardly active under standard growth conditions. Essential engineering thus required constitutive overexpression of lysine decarboxylase, which was realized using an episomal multicopy plasmid carrying the cadA gene under the control of the tac promoter [15]. To eliminate undesired cadaverine utilization by competing pathways 

The bottleneck for production was thus assigned to the supply of oxaloacetate [15]. The maximum cadaverine concentration obtained with the recombinant strain was 9.6gl with a yield of 0.12gg glucose [15]. Cell-surface display of -galactosidase extended the substrate spectrum toward cellobiose [69]. 

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