In our M.A.P.L.E. (Modular And Plastic-Looping E. coli) system the bioplastic, P(3HB), can be degraded and resynthesised. This is to allow the breakdown of such plastic without quality deterioration such that it can be converted into a 3D printing-ready form.

P(3HB) synthesis

In terms of synthesis, our engineered E. coli will be able to take in extracellular feedstock monomer into themselves. Such action is mediated by permease activity in their membranes. Once inside the cell, a cascade of reactions involving 4 different enzymes will take place. To generate these enzymes inside the cell they need to be genetically expressed in the first place. Therefore, it is necessary to model these expressions and how they could affect the corresponding enzymes produced within a certain amount of time.

1. ODEs

To model the genetic expression of these enzymes, transcription and translation need to be taken into account. At this stage, we have taken constitutive gene expression by mass action as the basis for our model and used ODEs to describe it:

2. Michaelis-Menten kinetics

3. Building the model (Matlab Simbiology)

4. Results

5. Experimental validation

P(3HB) degradation