A new paper, ssRNA Phage Penetration Triggers Detachment of the F-Pilus, was published in PNAS by the Zeng Lab with PhD candidate Laith Harb as first author. In this paper, Harb et al. used fluorescence microscopy to uncover a telling phenomenon associated with the infection of ssRNA phage MS2 or Qbeta through retractile pili: initial penetration of the viral payload causes breakage of E. coli conjugative F-pili. This provides a selective advantage for the infecting phage as a superinfection exclusion mechanism, and this phenomenon may be widespread among other pilus-specific phage systems. Based on this finding, ssRNA phages can be engineered as novel antibacterials to remove retractile pili (i.e. virulence factors) thereby to eliminate the dissemination of antibiotic resistance genes between bacteria and disarm pathogens. See this featured news article in AgriLife Today for more information on the published work.
