Ruminant emissions are responsible for a significant portion of the anthropogenic greenhouse gases that cause global warming. Methane emissions from cows are diffuse and difficult to treat, however, several solutions have been proposed which could reduce low (v/v) methane streams emitted from cattle up to ~30%. The novel Cattlelyst biofilter proposed by the Wageningen University & Research international Genetic Engineering Machine competition team is designed is to collect and convert the methane and ammonia emitted from cattle by means of a hood system and two genetically modified organisms under three layers of safety mechanisms. The goal is to engineer Escherichia coli into a suitable synthetic methanotroph. In this thesis synthetic methanotrophy was attempted to be expressed in a suitable methanotrophic strain SM1 or C1Saux. The resulting products are one pSEVA2610-sMMO plasmid containing the subunits of sMMO with a duplication in the mmoX gene. The other chaperone plasmid could not be achieved and methylotrophic growth of the SM1 and C1Saux strain was not shown. In the end the hypothesis has neither been confirmed or rejected. Synthetic methanotrophy for biofilters is becoming an increasingly relevant technology for tackling low concentrations of methane as multiple technological advances are made as explored in this thesis. It is expected that improvements in biofilter design such as concentrating methane in a hood, porous packing material, and specific cultures which are engineerable could make biofilters a useful tool in achieving the global methane pledge.