Poster Presentation 50th Lorne Proteins Conference 2025

EXPLORING PROTEIN INTERACTIONS BETWEEN ENVIRONMENTAL KLEBSIELLA AND THE BACTERIOPHAGES THAT RECOGNIZE THEM (#151)

Alex Hall 1 2 , Yan Li 1 2 , Rhys A. Dunstan 1 2 , Tze Young Y. Thung 1 2 , Kayla Cartledge 2 , Trevor Lithgow 1 2
  1. Infection Program, Biomedicine Discovery Institute and Department of Microbiology, Monash University, Carnegie, VIC, Australia
  2. Centre to Impact AMR, Monash University, Clayton, VIC, Australia

The genus Klebsiella is a significant contributor to bacterial infections in humans and is known to have a diverse environmental presence with many species and serotypes. Antimicrobial resistance (AMR) is of growing concern, with AMR strains from livestock and hospital settings spilling over into environmental reservoirs1. These reservoirs then can act as a source for community infection, adding to the already burdened healthcare system. The study of this environmental spread thus increased the urgency to facilitate efforts to track and control the spread of environmentally acquired Klebsiella infections. Bacteriophages hold potential for controlling Klebsiella strains, both in the context of infections and environmental reservoirs. These viruses are found in the same niches as their bacteria prey, including waterway environments where they are commonly sourced2. Waterway samples thus provide a potential and untapped source of environmental Klebsiella-targeting viruses. In this study, a One-Health approach was taken, with Klebsiella strains from across the Melbourne catchment region collected in collaboration with local Indigenous organisations3. These strains were, in turn, used to isolate bacteriophage from the same water samples. Whole genome sequencing and phenotypic tests were used to classify the species of these Klebsiella strains and annotate the phage genome. Supported by TEM of the phage & mass spectrometry of structural proteins, we used Alphafold2 to examine protein architecture for phage binding domains. Further work will evaluate the interaction mechanisms between phage proteins and their Klebsiella outer membrane receptors. It opens the way to understanding how AMR can be both potentiated and attenuated by environmental bacterium-bacteriophage relationships.

  1. Carroll, LM et. al. (2017) Whole-Genome Sequencing of Drug-Resistant Salmonella enterica Isolates from Dairy Cattle and Humans in New York and Washington States Reveals Source and Geographic Associations. Appl Environ Microbiol.
  2. Heller, D.M. et. al. (2024) SEA-PHAGES and SEA-GENES: Advancing Virology and Science Education. Annu Rev Virol.
  3. Thung, TY, et. al. (2024) Genetic variation in individuals from a population of the minimalist bacteriophage Merri-merri-uth nyilam marra-natj driving evolution of the virus. mBio