Targeted photothermal lysing of <i>E. Coli </i>via a geometrically-modified Au-binding M13 virus

Increasing antibiotic resistance (ABR) in bacteria is a continuing public threat to human health. Antibody functionalized nanoparticles (NPs) in conjunction with photothermal lysis have been successful in targeting and eradicating these pathogens. Yet, synthesis of antibodies is an expensive and time-consuming process. Alternative approaches capable of selectively delivering photothermally-active NPs to ABR bacteria are essential. In our work, a geometrically-modified, Au-binding M13 bacteriophage offers a novel solution to this challenge. Rod-shaped and spherically-shaped viral templates were created via chloroform interaction with the filamentous bacteriophage. Decorated with Au NPs, both of these scaffolds were capable of targeting E.Coli bacteria via attachment of exposed minor coat protein to the pathogen. Bactericidal studies of rods and spheroids were executed under a range of 532 nm laser irradiation conditions: power (0 - 60 mW) and time (0 - 20 min). Using geometrically-modified M13 scaffolds up to 65% of E.Coli were killed within 20 min. Through genetic modification of the minor coat protein the bactericide effects of these templates could be extended to target other pathogens. These findings advance efforts to engineer versatile and low-cost strategies to tackle ABR.