BtuB-Dependent Infection of the T5-like Yersinia Phage ϕR2-01

Abstract

Yersinia enterocolitica is a food-borne Gram-negative pathogen responsible for several gastrointestinal disorders. Host-specific lytic bacteriophages have been increasingly used recently as an alternative or complementary treatment to combat bacterial infections, especially when antibiotics fail. Here, we describe the proteogenomic characterization and host receptor identification of the siphovirus vB_YenS_ϕR2-01 (in short, ϕR2-01) that infects strains of several Yersinia enterocolitica serotypes. The ϕR2-01 genome contains 154 predicted genes, 117 of which encode products that are homologous to those of Escherichia bacteriophage T5. The ϕR2-01 and T5 genomes are largely syntenic, with the major differences residing in areas encoding hypothetical ϕR2-01 proteins. Label-free mass-spectrometry-based proteomics confirmed the expression of 90 of the ϕR2-01 genes, with 88 of these being either phage particle structural or phage-particle-associated proteins. In vitro transposon-based host mutagenesis and ϕR2-01 adsorption experiments identified the outer membrane vitamin B12 receptor BtuB as the host receptor. This study provides a proteogenomic characterization of a T5-type bacteriophage and identifies specific Y. enterocolitica strains sensitive to infection with possible future applications of ϕR2-01 as a food biocontrol or phage therapy agent.

Phage vB_YenS_P400, a Novel Virulent Siphovirus of Yersinia enterocolitica Isolated from Deer

“…The first siphovirus infecting Y. enterocolitica was PY54, a temperate phage, which, at the lysogenic state, replicates as a linear plasmid with covalently closed ends [27][28][29]. The first virulent Yersinia siphovirus mentioned in the scientific literature is phage R2-01, whose genome organization is similar to that of Enterobacteria phage T5 [19]. Hence, vB_YenS_P400 is the second and novel virulent siphovirus with a genome of 45.6 kb that is not related to any other phage.…”

“…These two phages not only infect various bio-/serotypes of Y. enterocolitica but also strains of Y. pseudotuberculosis if the medium is supplemented with calcium and magnesium cations [16]. Contrary to podoviruses and myoviruses, to date, only one virulent Yersinia siphovirus (phiR2-01) has been reported [19]. Phage phiR2-01 has a genome of 122,696 bp with long terminal repeats.…”