The role of biofilms in Campylobacter jejuni survival in the food chain

Campylobacter jejuni is the leading cause of bacterial foodborne poisoning in the developed world. The impact of infection is mainly economic, however the disease can lead to severe post infection complications, such as Guillain–Barré syndrome. Despite the fastidious nature of C. jejuni, it is able to survive food chain transit. One survival mechanism proposed to aid in C. jejuni food chain survival is its formation of, or incorporation into, biofilms. Biofilms are defined as a surface attached microbial population, surrounded by a self-produced extracellular matrix. Previous work has shown that biofilm formation by C. jejuni is increased in food chain relevant conditions, but C. jejuni biofilms have received little attention compared to other foodborne pathogens. The work presented here investigated how biofilms may enable C. jejuni survival within the food chain. In order to achieve this aim, investigation was carried out into three complementary areas. Initial investigations showed that supplementation of medium with chicken juice increased C. jejuni biofilm formation, due to the chicken juice conditioning the surface and allowing easier attachment of C. jejuni. In order to distinguish between the biofilm population and surface attached particulates, a novel method of staining C. jejuni biofilms, using a metabolic formazan dye, was developed and optimised. As biofilm formation by C. jejuni is relatively poorly understood, a broad investigation was performed to increase understanding of C. jejuni biofilm formation and structure. Finally, the role of extracellular DNA within the extracellular matrix was investigated. The results presented here suggest that C. jejuni is able to utilise biofilm formation as a food chain survival mechanism. However biofilm persistence can be limited by enzymatic treatment of the biofilm and thorough cleaning of surfaces, limiting the potential for surface contamination.

Name dc:type.qualificationname

phd

Level dc:type.qualificationlevel

doctoral

Grantor dc:publisher.institution

University of East Anglia

Year dc:date.issued

2015

Author dc:creator

• Brown, Helen

Language dc:language

en