Christian Gauthier, Hatfull Lab
Characterization of a Novel Prophage-Mediated Defense System in Mycobacteria
Temperate phages can enter two growth phases upon infecting a cell. They can grow lytically, making many copies of themselves and bursting the cell – in the process releasing their progeny to infect new permissive cells. Or they can grow lysogenically, integrating their genome into the host cell genome (replicating as the cell divides) and switching off lytic gene expression. For a host cell, the latter is preferable because 1) the cell survives infection, and 2) the phage defends against further infection by similar phages. Many temperate phages also encode mechanisms to prevent productive infection by heterotypic (unrelated) phages. One recently discovered example is the Cluster N mycobacteriophage, MichelleMyBell (MMB). The MMB prophage defends against a Cluster F phage called Tweety by a mechanism involving MMB genes 29-30. Studies to date involve characterization of the mechanism of MMB-mediated defense, determination of the stage of infection at which Tweety is blocked, and elucidating the counter-defense system used by phage Tweety.
Friday, October 12th
A219B Langley Hall