Author Date

2022-08-08

Degree Name

Department

Microbiology and Molecular Biology

College

Life Sciences

Defense Date

2022-08-02

Publication Date

2022-08-08

First Faculty Advisor

Julianne Grose

First Faculty Reader

Brian Poole

Honors Coordinator

David Erickson

Keywords

Klebsiella pneumoniae, bacteriophage, kaomega, Escherichia coli

Abstract

Klebsiella pneumoniae is a Gram-negative Enterobacteriaceae that is a common nosocomial pathogen causing pneumonia, infections in the bloodstream, wound infections, and meningitis. It has developed natural resistance to multiple antibiotics, most notably carbapenems which are often seen as the last line of defense against multi-drug resistant pathogens. Bacteriophages are being investigated as a promising alternative treatment to antibiotics in fighting these resistant pathogens. KaOmega, a Klebsiella pneumoniae bacteriophage, was isolated, sequenced, and annotated to characterize and understand its potential for use in a phage therapy. Characterization included Phyre2 analysis to predict putative protein functions based on structural homology, burst size to understand infection rates, and host range on both clinical and antibiotic sensitive Enterobacteriaceae to determine the specificity and clinical relevancy of KaOmega. Comparative genomics revealed that KaOmega belongs in the rV5-like family with numerous phages with over 80 percent identity to KaOmega. It encodes for a possible Clostridium tetani neurotoxin based on Phyre2 results as well as two arthropod antifreeze proteins. Both of these implicate horizontal gene transfer along with numerous other proteins included in both KaOmega and its host bacterium. KaOmega only infected Escherichia coli and Klebsiella pneumoniae in host range studies. It infected 33 percent of the carbapenem-resistant E. coli strains selected for their diverse serotypes and 50 percent of the CRE K. pneumoniae strains differentiated based on MLST sequence types. The narrow host range and clinical pathogen lysis rates are pertinent indicators of KaOmega’s clinical relevancy.