Mycobacteriophage (phage), are viruses that infect bacteria. All bacteria can be
infected by phage, and each bacterial species has a unique set of phage that infect them, making phage prime candidates for studying viral diversity and evolution. Some phage integrate their genome into the host genome upon infection (prophage), where they may potentially remain indefinitely, coevolving with the host, and providing growth factors and other benefits to the host. The purpose of my research is to characterize a prophage within the genome of the bacterial host Mycobacterium chelonae Bergey to determine if it is still functional and potentially impacting the fitness of the host bacterium. Characterization of this prophage has revealed that multiple genes are conserved with regard to both the DNA and protein sequences. The integrase cassette is highly conserved, complete with integrase and two potential repressors, suggesting the phage may be capable of excising from the host genome. Multiple structural genes including capsid and tail proteins are also conserved, suggesting the prophage may be capable of producing intact virions. At least two prophage genes are transcriptionally active. These include a predicted repressor and transmembrane protein. Expression of these genes suggests that the prophage does indeed have some potential for affecting the biology of the host bacterium. Experiments are currently underway to determine if intact virion particles are being produced during bacterial growth.
Sewell, Erica, "Characterizing the Intact Prophage of Mycobacterium chelonae Bergey" (2017). Honors College. 265.