NERC GW4+ DTP PhD studentship: Evolution and transmission of antimicrobial resistant bacteria through shellfish consumption and coastal bathing water exposure

Increasing resistance to antibiotics poses a threat to human health and society as serious as climate change (Chief Medical Officer). Therefore, there is an urgent need to understand the processes that lead to evolution of antibiotic resistance (also termed antimicrobial resistance or AMR) in order to safeguard our remaining drugs. The problem of AMR is essentially a case study in microbial evolution where human behaviour drives emergence of new resistance mechanisms as well as selecting for novel mutants1. The fact that genes can be readily mobilised between environmental and clinical bacteria means that understanding the microbial ecology of impacted ecosystems is of key importance. Previous work by Gaze et al estimated that over 6 million exposure events occur to AMR E. coli in UK bathing waters each year2. However, a key question is the role aquatic systems play in the evolution and transmission of AMR.

Project Aims and Methods. Experimental evolutionary approaches will be used to study selection for AMR in aquatic systems and in the oyster microbiome, as gene transfer is known to occur more frequently in such niches. Quantitative microbial risk assessment will be used to quantify the risk of AMR transmission through shellfish consumption and coastal water exposure. Objectives are: 1). Determine rates of AMR gene transfer in the shellfish gut relative to the water column using metagenomic approaches and marked AMR plasmids. 2). Quantify the levels of AMR bacteria present in coastal waters and shellfish at different points in the production cycle and chain. 3). Assess risk of exposure to recreational water users and shellfish consumers using quantitative risk assessment approaches.

Candidate. We are seeking a graduate with an interest / focus on microbiology who is interested in applying cutting edge research to solving real-world problems facing society. AMR research encompasses the study of evolution, ecology, epidemiology and environmental chemistry to inform regulatory and policy decision making to reduce the impact on human health.

Case Award. The Centre for Environment, Fisheries and Aquaculture Science (Cefas) is a world leader in marine science and technology, providing innovative solutions for the aquatic environment, biodiversity and food security. They are the UK’s most diverse centre for applied marine and freshwater science and research, covering an unrivalled breadth of specialist areas to provide a fully integrated, multi-disciplinary approach to all our customers’ needs. Cefas is the European Union reference laboratory (EURL) for bacterial and viral contamination of bivalve shellfish, so the student will have a unique opportunity to work in World-class laboratory involved in shellfish microbiology.

Training There are significant training opportunities as the project spans, microbial ecology, evolutionary biology and public health epidemiology. Dr Gaze’s lab currently holds research grants totalling £3 million on dissemination, evolution and transmission of AMR in the natural environment. Approaches include those used in molecular microbial ecology and evolution, such as quantitative PCR, metagenomics, experimental evolution and confocal microscopy. The student will also receive training in different aspects related to the project during placements at Cefas, including wet laboratory and microbiological aspects related to shellfish pathogens.