Evaluating Bacterial Acid Production and pH Dynamics in a Real-Time In-Vitro Polymicrobial Biofilm Model

Dental caries still remains a severe problem for both health and the economy. This oral disease is multifactorial and biofilm-dependent, caused by changes in the composition and metabolism of complex communities of oral biofilm. Streptococcus mutans is one of the most common species in oral biofilms associated with tooth decay; however, several other microbial communities are spatially organised into complex structural arrangements and extracellular matrices, contributing to cariogenic biofilm formation. The established biofilms ferment available carbohydrates to produce lactic acid. Lactic acid lowers the environmental pH and promotes demineralisation of the tooth’s enamel leading to the formation of dental caries. A preliminary collaborative study with Unilever established a dynamic in vitro model using the fluorescent pH nanosensors to assess acid production, (and thus the metabolic activity) of S. mutans in real-time within flow biofilms.  This studentship will extend this established Unilever-UoN collaboration to (i) build polymicrobial biofilm models that more realistically mimic the oral cavity, (ii) map environmental microniches within the biofilms, and (iii) monitor pH in real-time. Thereby, it will visualise pH modulation within mono- and poly- microbial biofilms to reveal the microbial contribution to damaging acidity. The model will be exploited to assess the impact of proof-of-concept treatments on pH modulation. The methods employed in this studentship will include a range of microbiological techniques, advanced fluorescent microscopy, and analytical science. The student will also spend time on placement at Unilever and be exposed to the industrial landscape, providing additional insight into Project Management, R&D Strategy, Regulatory, IP and Marketing.

The University of Nottingham provides first class facilities and learning environments supported by expertise and dedicated researchers. The supervisors have vibrant research groups hosted in state-of-the-art laboratories within the Cross-disciplinary Biodiscovery Institute (https://www.nottingham.ac.uk/research/research-areas/biodiscovery-institute/biodiscovery-institute.aspx) and the nearby Life Sciences Building. They are integral to the National Biofilm Innovation Centre (NBIC, https://www.biofilms.ac.uk). NBIC is an Innovation Knowledge Centre (IKC) funded by BBSRC and Innovate UK with the aims of establishing research networks and innovation capacity in the study of biofilms. The project will also benefit from the range of analytical platforms housed within the flagship nmRC facility at the University of Nottingham.

The training opportunities include cutting-edge fluorescent microscopy, transcriptomics, cryo-orbiSIMS, and molecular microbiology. The NBIC CTP.BITE training (https://www.biofilms.ac.uk/doctoral-training-centre/) delivers an ambitious training programme in biofilm science, engineering and technology as well as in commercialisation. Directly applied business-related training will also occur during the placement at Unilever. In addition, the University of Nottingham offers a host of practical training courses, there is an active research seminar programme and wellbeing support.