The University’s iGem team, comprised of eight students, is working to improve the wastewater treatment process by manipulating a bacterium called Paracoccus denitrificans.
iGem, which stands for international genetically engineered machines, is a worldwide competition where primarily undergraduate students build genetically engineered systems.
As explained on iGem.org, “iGEM teams work inside and outside the lab, creating sophisticated projects that strive to create a positive contribution to their communities and the world.”
According to Steven Scherping, fourth-year College student and iGem team member, the team — tentatively named “Sewage PD” after the organism they work with, Paracoccus denitrificans — went through several ideas before arriving at their idea for the November competition. They decided to engineer a bacteria to both nitrify and denitrify wastewater — key parts of the wastewater cleaning process.
This research is necessary because wastewater contains ammonia (NH3) and ammonium (NH4+) — both of which are toxic nitrogen compounds. The current treatment process uses two different bacteria to remove these dangerous compounds.
According to Scherping, the bacterium Nitrosomonas europaea (NE) performs the first step in the process — turning ammonia and ammonium into nitrates. These nitrates are still harmful, so a second bacterium, Paracoccus denitrificans (PD), turns the nitrates into nitrogen gas. Nitrogen gas is not harmful — it makes up 78 percent of the atmosphere.
While this process is very efficient, it is also very energy-intensive. The bacterium NE requires oxygen to turn ammonia into nitrates — this requires huge fans to shoot air into the wastewater so that the bacteria can function properly. The second bacterium, however, is much more efficient — it does not require any inputs to do its job of turning nitrates into nitrogen gas.
According to Scherping, the team is…