PhD Studentship: Synthetic Microbial Communities for Anaerobic Digestion of Waste to Biogas

Background: Lignocellulosic plant biomass is the most abundant waste product generated by society, agriculture and industry. By 2025, global cities will generate approximately 2.2 billion tonnes of solid waste biomass per year, with significant impacts upon health and the economy at both local and global scales. Natural communities of microorganisms convert waste biomass to methane-rich biogas that can be used as a sustainable and renewable green-energy source to generate electricity, heat and power, and biomethane for injection into the national gas grid and production of transport fuels. Anaerobic digestion (AD) plants and landfill sites are engineered environments where these microbial processes are harnessed for waste decomposition and biogas production. The EU is the largest global producer of biogas from biomass, with over 17,000 AD plants, and consequently, the microbiological conversion of solid waste residues to biogas in AD plants and landfill sites presents an unprecedented opportunity to leverage key enabling technologies for a sustainable bio-based economy for green-energy production. In turn, conversion of waste biomass to biomethane will mitigate the escalating environmental and social impacts of waste residues. However, substrate specificity and enzymatic hydrolysis of recalcitrant organic biomass is a major bottleneck to the efficiency of industrial bioconversion processes. Natural microorganisms found in landfill sites represent an unexplored repository of biomass-degrading enzyme diversity with the potential to enhance existing industrial biomass-conversion processes. Microbiome engineering build and test synthetic microbial communities (SynComs) that perform a specific function (e.g. waste decomposition) is a new research frontier. The development of synthetic biomass-degrading microbiomes has many potential applications, including bioaugmentation and optimisation of biomass conversion in AD plants and landfill sites towards an enhanced bio-based economy for waste management, environmental protection, and sustainable intensification of renewable energy generation. The aim of this project is to design and test synthetic microbial communities (SynComs) comprising anaerobic landfill microbiota for enhanced conversion of waste feedstocks into biogas. The candidate will utilise a range of methods including anaerobic microbial culture, synthetic community design and assembly, operate batch and continuous culture reactors, biogas analysis, quantitative PCR, 16S rRNA gene community profiling, metagenomics and computational analyses to address the following research objectives: Test the effects of inoculum size and mode of delivery on the establishment, stability and persistence of SynComs in anaerobic digestion processes. Design and test SynComs for the bioconversion of diverse feedstock types. Optimise minimal SynComs for waste biomass conversion to biogas. Methodological approach: The project combines anaerobic microbiology, genomics and computational biology with metabolic network models and enzyme biochemistry data generated by collaborators to design and test synthetic communities for waste biomass conversion to biogas. It combines elements of systems biology, computational and statistics, key skills listed in the ‘multidisciplinary and new ways of working’ framework. Techniques used: Anaerobic microbial cultivation, testing synthetic microbial communities in batch and continuous culture, biogas analysis, DNA extraction, PCR, 16S rRNA gene community profiling, metagenomics/genomics, computational analysis of DNA sequencing data. Eligibility: Applicants should hold, or expect to obtain, a first-class or upper second-class degree (or equivalent) in Microbiology, Environmental Engineering, Environmental Science, Biotechnology, Microbiology, Bioprocess Engineering, Chemical Engineering, or a related discipline. A Master’s degree in a relevant subject is desirable. Funding notes: This industry-funded PhD scholarship is only available for UK students. A PhD stipend will be provided for 3.5 years at the UKRI standard rate. UKRI standard rate