A Lambda-evo (λ_evo) phage platform for Zika virus E_DIII protein display

One of the most significant bacteriophage technologies is phage display, in which heterologous peptides are exhibited on the virion surface. This work describes the display of λ decorative protein D_λ linked to the E protein domain III of Zika virus (D_λ-ZE_DIII), to the GFP protein (D_λ-GFP), or to different domain III epitopes of the E_ZIKV protein (D_λ-TD), exhibited on the surface of an in vitro evolved lambda phage (λ_evo). This phage harbors a gene D deletion and was subjected to directed evolution using Escherichia coli W3110/pD_λ-ZE_DIII as background. After 20 days (20 cycles of dilution), the λ_evo phage developed a ~ 22% genome deletion affecting the non-essential λ b region, rendering a more stable phage that exhibited fusion proteins D_λ-ZE_DIII or D_λ-GFP but not D_λ-TD. Despite the λ_evo system was able to decorate itself with the D_λ-ZE_DIII protein, the production of viral particles was ~ 1000-fold lower than the λ wild-type, due to the unexpected D_λ-ZE_DIII protein aggregation into bacterial inclusion bodies. Decorated phages (10⁶ PFU (plaque forming units)/100 µl) were inoculated into BALB/c mice, and subsequent dot blot and Western blot immunoassays proved the production of murine antibodies against ZIKV (Zika virus). This multipurpose λ_evo phage display platform may be used interchangeably with other more soluble peptides, providing better yields. KEY POINTS: • λ_evo platform for displaying recombinant peptides. • Directed evolution to generate λ_evo with more efficient decoration. • Antigenic reaction in BALB/c mice by inoculating λ_evo with recombinant peptides.