PhD in Engineering Bacteria for Enhanced Degradation of Food-Associated Plastic Waste - BBSRC FoodBio DTP

We are offering a BBSRC FoodBioSystems DTP-funded PhD position with our College of Health, Medicine and Life Sciences, focusing on engineering bacteria for enhanced degradation of food-associated plastic waste.

If you have any questions about the project or would like to arrange an informal discussion, please reach out to Professor Ronan McCarthy at ronan.mccarthy@brunel.ac.uk.

As recognised by the UK Plastics Pact, novel solutions are urgently needed to tackle the scourge of waste plastic. From the globally produced 350 million metric tons of plastics per year, the food sector produces 40% of this. In the UK over half of food and drink products are wrapped in unnecessary plastic contributing to 29.8 billion avoidable pieces of plastic packaging annually.

These persistent plastics disrupt ecosystems at both macro- and microscopic levels, from inhibiting oxygen-producing bacteria to destabilising soil microbial communities.

This PhD will use an engineering biology approach to develop an enhanced bacterial strain capable of degrading multiple plastics simultaneously. By integrating high-performance plastic-degrading enzymes from diverse evolutionary lineages with regulatory circuits to control biofilm formation, this project will create a “super-degrader” strain that can attach to mixed plastic waste and convert it into valuable by-products.

This work will combine synthetic biology, biofilm and environmental engineering to address a global waste challenge.

Eligibility

As a PhD researcher, you’ll be at the forefront of a multi-disciplinary effort to engineer bacterial strains with enhanced plastic-degrading capabilities. You’ll gain experience in synthetic biology, biofilm engineering, and continuous-flow bioreactor technology while addressing real-world challenges in microplastic removal and wastewater treatment.

Project objectives

Objective 1: Build a Super-Degrading Chassis – Engineer bacterial strains (like Pseudomonas and Acinetobacter) to express multiple high-performing enzymes that target multiple plastic types simultaneously.
Objective 2: Boost Degradation with Biofilms – Design biofilm-enhancing circuits to create a “sticky” environment where bacteria can secrete higher concentrations of enzymes directly onto plastic waste.
Objective 3: Test in a Continuous Bioreactor – Apply engineered strains in bioreactors to degrade both single-use and mixed plastics, tracking the production of valuable by-products like ethylene glycol and terephthalic acid.
Objective 4: Scale-Up at a Wastewater Treatment Plant – Test the best-performing strains at a pilot-scale wastewater treatment plant (WWTP) at Cranfield University, assessing the strain’s real-world capacity to degrade microplastics in complex wastewater environments.

Training opportunities

The prospective student will benefit from a multi-disciplinary supervisory team with expertise spanning microbiology, synthetic biology, bioinformatics, biofilms, and water science. They will receive training in a range of cutting-edge techniques, including modular genetic circuit design, biofilm flow cells, and microscale bioreactors. A key highlight is the close association with the Environmental Biotechnology Innovation Centre (EBIC) led by co-supervisor Prof Coulon. The student will join EBIC’s Early Career Network, offering access to regular career development and training events. Additionally, a 3-month placement at SEBI Group which will provide hands-on industry experience in food packaging production and sustainability considerations, enhancing the student’s practical and professional skills.

Project supervision plan

You will be primarily based in the McCarthy Lab at Brunel where you have a core supervisory team consisting of Professor McCarthy and Professor Fern. You'll have weekly 1:1 meetings with Professor McCarthy, and Professor Fern will join these meetings monthly, and you'll be provided with feedback and support. You will meet the wider supervisor team at least every 6 months. You will also have an independent Research Development Advisor who you will meet quarterly. Brunel has a structured PhD progression programme where progression review meetings are held at 9, 20, 30 and 40 months. At these meetings, an independent academic panel will review your progress, provide detailed constructive feedback and highlight prospective development opportunities. You will be based in the Hassard Lab for the majority of Objective 4, where you will have weekly meetings with Dr Hassard.

Stipend (Salary)

FoodBioSystems DTP students receive an annual tax-free stipend (salary) that is paid in instalments throughout the year. For 2024/25 this is £21,237 (at Brunel University) and it will increase slightly each year at the rate set by UKRI.

Equity, diversity and inclusion

The FoodBioSystems DTP is committed to equity, diversity and inclusion (EDI), to building a doctoral researcher (DR) and staff body that reflects the diversity of society, and to encouraging applications from under-represented and disadvantaged groups.

Our actions to promote diversity and inclusion are detailed on the FoodBioSystems DTP website and include:

• Offering reasonable adjustments at interviews for shortlisted candidates who have disclosed a disability or specific learning difference

• Guaranteed interview and applicant mentoring schemes for applicants, with UK home fee status, from eligible under-represented ethnic groups.

These are opt-in processes. Our studentships are offered on a part-time basis in addition to full-time registration. The minimum registration is 50% FT and the studentship end date will be extended to reflect the part-time registration.

How to apply

PhD Opportunities - FoodBioSystems

Meet the Supervisor(s)

Ronan Mccarthy - Ronan gained his Bachelor of Science in Genetics with first class honours from University College Cork, Ireland in 2010 and was awarded the title of College Scholar. In autumn 2010, Ronan was awarded an Irish Research Council PhD Scholarship to study novel biofilm inhibition strategies against the opportunistic pathogen Pseudomonas aeruginosa in the lab of Professor Fergal O’Gara. In 2014, Ronan joined the research group of Professor Alain Filloux at the MRC Centre for Bacteriology and Infection at Imperial College London. As a Postdoctoral Research Associate, Ronan interrogated the second messenger signalling cascades that govern the biofilm mode of growth in Pseudomonas aeruginosa and Agrobacterium tumefaciens. Following on from his time at Imperial College Ronan joined the Microbiology Department at the Animal and Plant Health Agency where he used host transcriptomics and pathway analysis to profile the host response to infection. He joined the Biosciences Division in Brunel University to continue his analysis of the regulatory networks that govern pathogenicity, antimicrobial resistance and biofilm formation in the Gram negative opportunistic pathogens Pseudomonas aeruginosa and Acinetobacter baumannii. In 2021, Ronan was awarded a BBSRC New Investigator Award to study the regulation of desiccation tolerance and biofilm formation in Acinetobacter baumannii and to identify compounds that could disrupt these survival mechanisms. He has also expanded into the field of biofilm engineering, using synthetic biology approaches to give control over bacterial biofilm formation and using these tools to tackle environmental challenges such as plastic waste. As a PI he has secured funding from the BBSRC, NC3Rs, Academy of Medical Sciences, Horizon 2020, British Society for Antimicrobial Chemotherapy, Innovate UK, NERC and the Medical Research Council.

Related Research Group(s)

Biomedical Engineering - Research in the growing multi-disciplinary field of advanced technology as devices, processes and modelling to advance health through improvements in therapy, diagnosis, screening, monitoring and rehabilitation.

Antimicrobial Innovations Centre - The central aim of the Antimicrobial Innovations Centre (AMIC), is to address key challenges related to antimicrobial resistance, through focused interdisciplinary collaboration and cutting-edge research, positioning it at the forefront of addressing global health and planetary challenges.