Optimization of Growth Conditions for Methanol Consumption in Escherichia coli Expressing Methylotrophic Genes

Abstract

A variety of experiments were carried out to determine the optimal growth conditions for newly developed strains of Escherichia coli expressing methylotrophic genes. Yeast extract was determined to be the ideal co-substrate for methanol incorporation into biomass, providing a statistically significant biomass yield from 0.22 g biomass/ g yeast extract without methanol to 0.28 g biomass/ g yeast extract in the presence of methanol. Experiments were then conducted in continuous culture using varying yeast extract concentrations as a co-substrate with methanol in order to determine optimum growth conditions for methanol consumption. Finally, an adaptive evolution experiment was conducted in an attempt to induce a population of E. coli that showed improved growth on methanol over the genetically engineered base-strain.