Product resistant biocatalysts for methacrylate ester manufacturing

Polymethylmethacryalte is a bulk plastic used in the manufacture of acrylics. It is a polymer of methylmethacrylate (MMA) which can be chemically synthesized via a number of well established processes. Fluctuating costs of the crude oil feedstock required for chemical synthesis of MMA now drive research into developing biocatalytic production of MMA. A methacrylate ester which can be chemically converted to MMA has been successfully synthesized in genetically engineered Escherichia coli. This ester is toxic to the biocatalysts at low concentration, and thus far can only be produced at relatively low product titres.

As a result a number of non-producing strains of E. coli have been adapted to become resistant to extracellular methacrylate ester. This project will investigate the best product-resistant mutants from previous research, introducing genes required for methacrylate ester synthesis and carrying out fed-batch fermentations to elucidate whether the mutants generated from extracellular methacrylate ester (a) can generate higher product titres than non-resistant strains, and (b) show any increased resistance to methacrylate ester within the biocatalyst.

Analysis of the outcomes of these fermentations using a variety of 'omics' approaches should provide a comprehensive picture of the cross-talking mechanisms implicated in methacrylate ester resistance, as well as providing a framework for reverse engineering rationally designed resistant mutants.