Cloning & Homologous Expression of Aspartate Kinase Gene

Cloning and homologous expression of aspartate kinase gene in a non-model bacterium to increase metabolic flux towards natural product biosynthesis.

During Aspartate metabolism, the conversion of Aspartate to Homoserine is mediated by aspartate kinase (AK), a protein with isozymes lysC, metL, and thrA, and aspartate-semialdehyde dehydrogenase (asd). The enzyme metL is predicted to be mainly responsible for the conversion of aspartate semialdehyde to homoserine.  Homoserine is the suspected precursor to a secondary metabolite of interest, “Metabolite A”. In theory, by engineering a bacterial strain to overexpress metL, metabolic flux would be directed away from branching metabolic pathways and towards homoserine production. In turn, given higher levels of available homoserine, this could lead to an increase in the biosynthesis of Metabolite A. This study aims to examine whether and how the overexpression of metL affects the titer production capacity of a natural product in a non-model bacterial strain.