Kinetic Analysis of Bacteriophage Sf6 Binding to Outer Membrane Protein A Using Whole Virions

Natalia B. Hubbs; Mareena M. Whisby-Pitts; Jonathan L. McMurry

The copyright holder for this preprint (which was not peer-reviewed) is the author/funder. . https://doi.org/10.1101/509141 doi: bioRxiv preprint Bacteriophage Sf6 is a short-tailed dsDNA virus that belongs to a subgroup of the family Podoviridae, the "P22-like" phages [22] . Sf6 infection of Shigella flexneri is a two-step process that utilizes both glycans and proteins during infection. First, Sf6 reversibly recognizes and then hydrolyzes LPS via its tailspikes [23, 24] . Second, Sf6 interacts irreversibly with a protein receptor to commit to infection [25] . Sf6 preferentially uses OmpA, but can also use OmpC when OmpA is absent [25] . Sf6 can likely utilize a third, as of yet unidentified receptor, as infection still occurs in the absence of both OmpA and OmpC [25] . Bacteriophage Sf6 has an inherent ability to utilize multiple Omps for infection [25] . Although host range studies have generated mutants of other phages that can switch to utilize alternative receptors when under selection pressure [17, 18, 26, 27] , an innate ability to recognize multiple receptor types is not a common phenomenon, making Sf6 somewhat unique.