Does LK-Sleep Give Bacterial Cells Immunity Against Other Phages?
Student Presenter(s): Elsy Ventura
Faculty Mentor: Bryan Gibb
Department: Biological and Chemical Sciences
School/College: College of Arts and Sciences, Long Island
Bacteriophages are viruses that infect and kill bacterial cells. Phages are specific for the bacteria they infect, often infecting a single species or even a subset of strains. Phages consist of nucleic acid DNA or RNA enclosed in a protein shell called a capsid. A phage infection can proceed through one of two lifecycles, lysogenic or lytic. The lytic cycle is when the virus replicates in the host and the newly formed phage particles are released when the host cell bursts. During the lysogenic cycle, the phage injects its genome into the bacterium and it is inserted into its chromosome. Every time the bacterial cell divides, the daughter cell inherits a copy of the phage. A lysogenic bacteriophages can resume lytic growth stochastically or based on exogenous triggers. Phages LK-Sleep, Shaolin and RW form hazy clearings called plaques when infecting the host bacterial strain. This suggests that these phage do not completely kill the bacteria and may be entering the lysogenic cycle. We set up infections to isolate stable lysogens with each of the three phages. The lysogens with LK-Sleep and Shaolin were then able to resist infection challenges from each other because they are closely related, but was susceptible to infection from a more distantly related phage, RW. This study will allow us to see if a temperate phage can give a bacterial cell immunity to other phages. We will be able to see if temperate phages give bacterial cells an advantage illustrating how bacterial cells.