Developing tractable model systems for filamentous bacteria in wastewater treatment

Wastewater treatment (WWT) is arguably the most important biotechnological application in the world. Each day, large volumes of influent wastewater are processed in municipal WWT plants so that safe effluent is returned to the water cycle. It is the metabolic activity of flocculating bacteria that make this process work. In short, the bacteria degrade dissolved pollutants in the wastewater whilst forming compact flocs, which are then separated from the liquid under gravity. WWT flocs consist of micron-sized bacteria "glued" together by "sticky" polymers. Understanding the interactions underpinning polymer-mediated bacterial (colloidal) aggregation lies in the domain of soft matter. Therefore, the student will use the principles of soft matter to develop computational models for WWT bacteria, with a particular emphasis on filamentous cells. These are crucial for floc strength and structural integrity, however, too many filaments disrupt floc structure and give rise to a diffuse network that prevents compaction and subsequent settling.