Foam created by bacteria can create operational difficulties for wastewater treatment plants, but an exciting new discovery from La Trobe University researchers has the potential to solve this costly and hazardous issue.
Having published the finding in Nature Microbiology, Associate Professor Steve Petrovski said the potential solution was discovered during his research into a particular bacterium well known for causing troublesome foams in wastewater treatment plants
“This foam reduces the quality of effluent and creates a hazardous work environment at the plant. It costs the industry billions of dollars each year and makes the plants inefficient, yet there are no effective ways to control these foams,” he said.
“One particular bacterium — Gordonia amarae — is notorious for causing persistent and stable foams in wastewater treatment plants.
“Through our work to isolate a phage that will target G. amarae, we accidentally stumbled across another potential solution — a previously unknown microscopic parasite attached to the bacterium.”
The team identified previously unknown defence mechanisms, explaining why the bacteria is hard to combat with bacteriophages, Petrovski said.
“But the microparasite, which we have named Mycosynbacter amalyticus, latches onto G. amarae and in fact kills it. This may represent a promising biocontrol strategy to prevent wastewater foaming,” he said.
“Some organisms related to G. amarae can also cause disease in humans and animals such as nocardiosis and bacteremia, and this novel ultrasmall bacterium could potentially be the cure.
“This microparasitic bacterium could have medical implications and be used to control human and animal infections. We may be able to eliminate or control the infectious bacterium generating an alternative treatment option that does not require antibiotics.”
Petrovski said the team is now studying the way the newly discovered organism grows and ways in which it can be applied to wastewater treatment plants.
“We already know that it will reduce or eliminate G. amarae and some of its relatives in pure culture in the laboratory. We now need to test this in activated sludge,” he said.
“The next phase of this research will be understanding how this organism infects and kills the host bacteria. We will also be working with wastewater treatment plants to understand how this organism behaves in activated sludge and determine the best way to apply it to activated sludge systems.
“We also have an ongoing collaboration with the School of Pharmacy at La Trobe University and will investigate ways to develop pharmaceutical products to deliver this organism to infection sites.”
Petrovski said there are also plans for future commercialisation, which is a promising prospect for wastewater treatment plants worldwide.
“Our goal is eventually to create a product containing this microparasite that could be commercially available for use by the wastewater treatment sector to control foaming in wastewater aeration tanks and anaerobic digesters,” he said.