Role of Tail Fiber Protein in Attaching Riemerella anatipestifer to Phage

  Objective  Role of tail fiber protein (TFP) plays in adhering Riemerella anatipestifer by CRP2 phage was investigated.

  Method  The putative TFP gene of ORF70 was cloned. The recombinant expression vector pET28a(+)-TFP was constructed and induced to express in E. coli BL21(DE3). The recombinant protein was purified by Ni-NTA affinity chromatography. ELISA was used to determine the binding effect of the recombinant protein with the outer membrane protein (OMP) of host bacteria. A competitive adsorption test was performed to determine the adhering effect of the CRP2 protein.

  Result   The recombinant plasmids of pET28a(+)-TFP was successfully constructed and expressed in E. coli. The purified recombinant protein rTFP could bind to the OMP of or suppress the CRP2 adsorption to the host bacteria.

  Conclusion  The TFP encoded by ORF70, one of the receptor binding proteins of CRP2 phage, was confirmed to adhere to the host bacteria OMP facilitating the subsequent bactericidal effect.