New tricks for phage

In the latest issue of Molecular Cell, the Maxwell, Davidson and Moraes labs identify and characterize Aqs1, a multi-purpose DMS3 phage protein. Aqs1 binds and inhibits LasR, which is required for quorum sensing and the release of several anti-phage defenses in Pseudomonas aeruginosa. But that’s not all. Aqs1 also binds PilB, and thereby blocks pilus assembly. Since the bacterial pilus helps phage to infect, Aqs1 prevents further phage infection.

Phages and bacteria have been waging war since the dawn of life. By investigating this molecular warfare we have been able to identify molecular machines that have expanded our toolbox of molecular biology enzymes, such as restriction enzymes and CRISPR/Cas systems. Thus the identification of new players may help expand the types of genetic manipulations that are common in our labs today.