|Title||Separating Functions of the Phage-Encoded Quorum-Sensing-Activated Antirepressor Qtip.|
|Publication Type||Journal Article|
|Year of Publication||2020|
|Authors||Silpe, JE, Bridges, AA, Huang, X, Coronado, DR, Duddy, OP, Bassler, BL|
|Journal||Cell Host Microbe|
|Date Published||2020 Feb 19|
Quorum sensing is a process of chemical communication that bacteria use to track cell density and coordinate gene expression across a population. Bacteria-infecting viruses, called phages, can encode quorum-sensing components that enable them to integrate host cell density information into the lysis-lysogeny decision. Vibriophage VP882 is one such phage, and activation of its quorum-sensing pathway leads to the production of an antirepressor called Qtip. Qtip interferes with the prophage repressor (cIVP882), leading to host-cell lysis. Here, we show that Qtip interacts with the N terminus of cIVP882, inhibiting both cIVP882 DNA binding and cIVP882 autoproteolysis. Qtip also sequesters cIVP882, localizing it to the poles. Qtip can localize to the poles independently of cIVP882. Alanine-scanning mutagenesis of Qtip shows that its localization and interference with cIVP882 activities are separable. Comparison of Qtip to a canonical phage antirepressor reveals that despite both proteins interacting with their partner repressors, only Qtip drives polar localization.
|Alternate Journal||Cell Host Microbe|