Phage rivalry and receptor rharing in hypervirulent Klebsiella pneumoniae

Dr. Belinda Loh will give a seminar entitled "Phage rivalry and receptor rharing in hypervirulent Klebsiella pneumoniae".

This seminar is organised by the ELI-M (Applied microbiology) division of the Earth and Life Institute.

Dr. Belinda Loh is the Head of Antimicrobial Biotechnology Unit at the Fraunhofer Institute for Cell Therapy and Immunology (Leipzig, Germany).

Abstract

Klebsiella pneumoniae is a major hospital and community pathogen known for its multidrug resistance and hypervirulent strains. 

We isolated three lytic bacteriophages — Spear, Loop, and Shorty — from sewage using a hypervirulent K. pneumoniae K1 ST23 strain as the host. Despite major genomic and structural differences, all three phages specifically targeted the K1 serotype and depended on the capsular polysaccharide (CPS) for infection. 

Interestingly, while Loop and Shorty completely lost binding to CPS-deficient mutants, Spear retained partial binding, suggesting an additional receptor. When combined, Spear and Loop showed antagonism rather than synergy, likely due to competition for the same CPS receptor. 

Overall, these results show that genetically unrelated phages can converge on the same bacterial target, highlighting the importance of receptor profiling and careful phage selection when designing effective therapeutic cocktails against K1-type K. pneumoniae.