Mechanism of how Campylobacter jejuni mediates protection from bile acid stress (ProBAS) to co-cultivated bacteria

• Applicant: Professor Dr. Uwe Groß, since 8/2022
• Subject Area: Medical Microbiology and Mycology, Hygiene, Molecular Infection Biology ; Metabolism, Biochemistry and Genetics of Microorganisms
• Term: from 2019 to 2024
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 428673465

• Final Report Year: 2024

Final Report Abstract

When bacteria enter the gastrointestinal tract and attempt to colonize the gut, they encounter a range of environmental challenges, including the presence of the local gut microbiome, but also the exposure to harmful substances like bile acids. Studying how gut pathogens adapt to these challenging conditions is vital for understanding the process of colonization success. We investigated in this project the proteomic adaptions of Campylobacter jejuni and of two Enterococci species in co-incubation scenarios in the absence and presence of bile acids. Mass spectrometry was applied to study three subtopics. (i) Comparative analysis of proteomic adaptations in E. faecalis and E. faecium was performed after long term bile acid exposure. (ii) Characterization of Campylobacter jejuni proteome profiles in co-incubation scenarios with E. faecalis, E. faecium and S.aureus was performed. This project part resulted in a publication in Frontiers in Microbiology. (iii) Knock-out mutants for three C. jejuni genes known to be associated with bile acid resistance were generated. Subsequently, the phenotype of the mutants, particularly their bile acid resistance profile as well as proteomic changes compared to the wild type strain were analysed. Together, these projects added valuable data on proteomic adaptations that occur when pathogens are exposed to stress factors typical for the environment of the gastrointestinal tract.

Publications

• DGHM conference, Berlin 2022: Proteomic changes of Enterococcus faecium und Enterococcus faecalis during bile acid stress.
  Annika Dreyer, Wolfgang Bohne, Christof Lenz, Uwe, Groß Andreas & E. Zautner
  
• Characterization of Campylobacter jejuni proteome profiles in co-incubation scenarios. Frontiers in Microbiology, 14.
  Dreyer, Annika; Lenz, Christof; Groß, Uwe; Bohne, Wolfgang & Zautner, Andreas Erich
  
• Comparative analysis of proteomic adaptations in Enterococcus faecalis and Enterococcus faecium after long term bile acid exposure. BMC Microbiology, 24(1).
  Dreyer, Annika; Lenz, Christof; Groß, Uwe; Bohne, Wolfgang & Zautner, Andreas Erich