Salmonella biofilm formation, virulence, transmission and vaccine development

Project Team: Aaron White

Collaborators: Michael Wu (Veterinary Biomedical Sciences); Cagla Tükel (Temple University)

Most people who get sick from Salmonella recover without treatment. However, approximately 5% of people develop an autoimmune condition known as reactive arthritis. Our team discovered that a biofilm protein produced by Salmonella could be what causes this autoimmune response.

We know that Salmonella can form biofilms—dense collections of bacteria that stick together—which help it to survive outside of a living host. With collaborators, our team discovered that biofilms (previously only thought to form in the environment) can form in the gut before leaving the body. This strategy enhances survival in the environment which increases the likelihood of an outbreak or additional infection.

Recently, White lab trainees succeeded in building a ‘dual-reporter’ strain of Salmonella that allows us to track individual cell types within an infection. We will use this dual reporter strain to explore the interactions between different Salmonella cell types and the host immune system, leading to an improved strategy for vaccine development.

Salmonella biofilms produce an amyloid protein called curli, which are thin fibres that protrude from the surface and help the bacteria stick together like velcro. A buildup of similar amyloid proteins has been associated with neurodegenerative diseases such as Alzheimer’s, Parkinson’s, and amyotrophic lateral sclerosis (ALS, or Lou Gehrig’s disease). The next phase of research will determine if curli interacts with the amyloid proteins involved in these devastating human diseases.