Figure 1.

Metabolic enzyme expression balancing and modeling. (A) A hypothetical two-gene metabolic pathway. Overexpression of enzymes may cause a burden to the cell; the intermediate may be non-productive by reacting with alternative enzymes, causing cytotoxicity, or leaving the cell by active or passive transport. (B) The associated production landscape showing that for one or a combination of the above-stated scenarios, moderate gene expression is optimal. (C) An example of the landscape predicted by a regression model trained on 100 randomly sampled points from the true landscape. The correlation coefficient shown is between the predicted and true values in the 20-by-20 discretized space.