Ethylene Synthesis by Genetically Modified Rhodococcus opacus PD630 on Synthetic Human Urine

To accommodate NASA's Center fro the Utilization of Biological Engineering in Space objectives for genetically modified organisms to produce materials and food sources required for Mars colonization, we are modifying a bacterium to produce ethylene from genetic modification. Our non-model bacterium, Rhodococcus opacus PD630, is a bacterium that has been proven in literature to be metabolically diverse enough to eat urea, a compound largely found in human urine. It has also been found to continue to grow at the same time as it is accumulating fatty acids, a trait that is useful for our research as it would allow fatty acids to be convertible in large quantities to ethylene if provided the correct gene through plasmid introduction. Growth curve studies on Luria-Bertani Broth and synthetic human urine were conducted on R. opacus PD630 to establish the growth behavior of the wild-type bacteria and then a crafted plasmid consisting of a pBAV1K backbone, efe gene, and PsbA promoter- Ribosome Binding Site was introduced into competent cells. Post plasmid introduction, growth media studies and plasmid identification through selective digestion would be conducted to ensure pure bacterial colonies for eventual ethylene production. Ethylene production would then be promoted through bacteria growth in synthetic human urine and kanamycin, later to be detected via gas chromatography.