PartD: system development

PartD of the project is concentrated on research application and the development of a working physical system.
Our project aims to synthesise biopolymer capsules to contain bacteria-infused 5mm diameter agarose pellets. The genetically engineered Pseudomonas putida and Pseudomonas fluorescent bacteria strains will be genetically engineered to enzymatically break down DCM, a common toxic waste product of industry, into less harmful and potentially useful HCl and formaldehyde, within cellular microcompartments.
The purpose of the biopolymer is to act as a DCM diffusion barrier, such that the rate of intake is less than or equal to the rate of DCM breakdown by the strain, allowing the capsules to be in direct contact with higher [DCM] while restricting the local [DCM] to our bacteria to ~20mM (viable). Synthesising capsule density between that of water and DCM, will suspend these at the interface of a biphasic mixture of the two, optimising turnover efficiency of the process.
Our work will involve the synthesis of cellulose-modified biopolymers, by two classes of reaction: acyl chloride esterification and Williamson ether synthesis. The first class of reactions will use microcrystalline cellulose powder substrate, carried out with various stoichiometries of AcCl, at 0°C. The second class of reactions will use NaH as base in various stoichiometries, under N2 atmosphere, followed by dropwise addition of corresponding stoichiometry of benzyl bromide. Modification aims to balance increasing diethyl ether solubility, while retaining chemical resistance to DCM. The polymer will be coated on an agarose substrate, eventually containing engineered strains of Pseudomonas bacteria, capable of breaking down DCM up to 20mM.