Beyond the Biofilm: Pathogen Persistence in Food

As part of #BiofilmWeek, our Beyond the Biofilm series is spotlighting exciting and diverse research from across our NBIC partner institutions. We hear from early career researchers, PhD students, and Interdisciplinary Research Fellows who are contributing fresh perspectives to biofilm and antimicrobial resistance (AMR) science. Their stories highlight not only innovation in research, but also the value of inclusion, collaboration, and diversity in driving scientific discovery.

In this blog, Lucy Sutton, a PhD candidate at the University of Southampton, shares her journey into microbiology, from an early passion for environmental protection to studying how Listeria biofilms respond to sanitisers in the fresh food supply chain. She reflects on the key experiences and mentors that shaped her path as a researcher from a non-traditional background.

Tracing a Path from Ecology to Biofilms

 

My journey into science was inspired by the Gulf of Mexico oil spill, which sparked my passion for protecting the environment. That led me to study Biology at Cardiff University, focusing on conservation and ecology. During my second year, I spotted an advert for a microbiology studentship at Heath Dental School in the Advanced Therapies group, studying Streptococcus gordonii and Candida albicans in the oral microbiome – my first encounter with biofilms!

Pathogen Persistence in Food

Lucy presenting at the 21st International Symposium on Problems of Listeria and Listeriosis.

It was completely outside my comfort zone, but with the encouragement of my personal tutor (who even taught me how to pipette in his spare time!), I applied and was mentored by an inspiring researcher who taught me the microbiology skills I still use today. Even then, I remained passionate about sustainability, and my final year project explored Burkholderia vietnamiensis as a potential alternative crop biocontrol.

Coming from a non-academic background, I didn’t think that research was a realistic path for me. That’s why the encouragement and support from mentors and peers along the way, especially early on, made all the difference. It showed me that curiosity and perseverance can open doors.

 

Exploring Listeria Resilience in the Food Sector

 

My research focuses on food safety and security, specifically how Listeria biofilms respond to oxidative sanitisers within the fresh food supply chain of leafy greens.

My PhD was funded by the BBSRC SoCoBio Doctoral Training Partnership and Vitacress, where I also gained valuable field experience during an industry secondment.

Listeria monocytogenes is a Gram-positive foodborne pathogen notorious for its ability to grow at refrigeration temperature and form resilient biofilms. In the fresh food industry, where produce is often consumed without cooking, this makes it a serious concern. Biofilms are far more tolerant to sanitisers than free-living cells, so understanding how to effectively remove them is crucial for food safety.

I aim to uncover how Listeria biofilms tolerate sanitisers, and to use that knowledge to inform cleaning procedures in food processing environments, ultimately helping to reduce the number of future listeriosis outbreaks.

We’ve found that L. monocytogenes biofilms show reduced susceptibility to several commonly used sanitisers. You can read more about our findings in my recently published paper.

 

Pathogen Persistence in Food

Mint and basil plants grown in Listeria inoculated soil during PhD placement.

Pathogen Persistence in Food

EDIC/EF microscope image of Listeria monocytogenes Scott A biofilm following chlorine treatment.

Encouraging Confidence and Belonging in Research

 

After finishing my undergraduate degree, I took a three-year career break working at Starbucks. It was difficult to get back into science after being away from the lab for so long; I felt rusty and unsure of myself. When I began my PhD, I was lucky to have incredibly supportive lab mates who helped me rebuild my confidence and get back into the rhythm of research.

Experiences like this have made me especially aware of the equality, diversity and inclusion (EDI) challenges within research. Many brilliant people don’t realise research is a career option for them, or they don’t think that they’re “smart” enough. We need to show that science is open to everyone, regardless of background or career path! I’d love to see more flexible routes into research, including return-to-science programmes and clearer guidance for those coming from diverse backgrounds. Institutions and organisations also need to look after their researchers, with stronger advocacy for mental health and more secure funding and job prospects, especially within academia. Finally, mentorship schemes can make a huge difference for early career researchers.

 

Building Confidence Through Support and Opportunity

 

I’ve been fortunate to have support and encouragement from many people throughout my journey, but Dr Alison Jack, who supervised the microbiology studentship I mentioned earlier, has been a huge influence. Without her, I might never have discovered microbiology (or even known what a biofilm was!). Her mentorship truly set me on my current path.

The National Biofilms Innovation Centre (NBIC) has been incredibly supportive throughout my PhD. I’ve attended four of their training courses, which were invaluable to my development. They also gave me the opportunity to speak at their annual Summit in Cardiff and present a poster at the Biofilms 11 conference – something that once felt impossible given my fear of public speaking! These experiences have boosted my confidence and expanded my network across the biofilm community.

 

On to the Next Adventure

 

I am currently preparing for my PhD viva, which is my main focus right now – and then it’s on to the next adventure: job hunting. As I look ahead, I’m excited by the versatility of biofilms, from applications in skincare and biotechnology to water treatment and pollution control, and the potential for biofilm science to create positive impact across so many sectors.

 

Find out more

 

If you are interested in learning more about Lucy’s work and would like to connect, please contact NBIC at nbic@biofilms.ac.uk

Lucy Sutton, PhD candidate at the University of Southampton.

 

Pathogen Persistence in Food