Publication Date


Advisor(s) - Committee Chair

Rodney King (chair), Simran Banga, Claire Rinehart

Degree Program

Department of Biology

Degree Type

Master of Science


Mycobacteriophages are a group of phages that infect members of the genus Mycobacteria. Previous studies have conducted extensive comparisons of the mycobacteriophage genomes and amino acid sequences to establish different phage families. MooMoo is a singleton mycobacteriophage that has been characterized due to its lack of appreciable homology to other phages. Some of its unique properties include its structure and the isolation of a mutant that causes clear plaque phenotypes. The experiments described in this thesis identified three MooMoo phage (gp87, gp90, and gp91) encoded proteins that are toxic to the bacterial host, Mycobacterium smegmatis.Through the use of a novel 2-hybrid plamid-based system, the alpha subunit of a class 1b ribonucleoside-diphosphate reductase from M. smegmatis was successfully identified to interact with the MooMoo gp87 protein. We also used bacterophage recombineering with electroporated DNA (BRED) to delete MooMoo gp19 to determine if 1) the gene is essential and 2) if the absence of gp19 results in a clear plaque phenotype. A phage population that only contained the gp19 deletion was not identified; therefore, the mutant presumably grows in the mixed plaque through the assistance of wild type helper phage. Identifying and characterizing phage-encoded toxic genes provides a new approach in understanding both phage- host interactions and identifying potential new drug targets. The emergence of multi-drug resistant bacterial strains requires new and alternative treatment options to antibiotics, and cytotoxic proteins encoded by mycobacteriophages may be an option.


Environmental Microbiology and Microbial Ecology | Life Sciences | Microbial Physiology | Microbiology | Other Microbiology | Virology