부산대학교 도서관

Bacteriophages present huge potential both as a resource for developing novel tools for bacterial diagnostics and for use in phage therapy. This is also valid for bacteriophages specific for Yersinia enterocolitica. To increase our knowledge on Y. enterocolitica -specific phages we characterized two novel yersiniophages. The genomes of the bacteriophages vB_YenM_TG1 (TG1) and vB_YenM_ΦR1-RT (ΦR1-RT), isolated from pig manure in Canada and from sewage in Finland, consist of linear double-stranded DNA of 162,101 and 168,809 bp respectively. Their genomes encode 262 putative coding sequences and 4 tRNAs genes, and share 91% overall nucleotide identity. Based on phylogenetic analyses of their whole genome sequences and large terminase subunit protein sequences, a genus named Tg1virus within the family Myoviridae is proposed with TG1 and ΦR1-RT as member species. These bacteriophages exhibit a host range restricted to Y. enterocolitica, and display lytic activity against the epidemiologically significant serotypes O:3, O:5,27, and O:9 at and below 25°C. Adsorption analyses of LPS and OmpF mutants demonstrate that these phages use both the LPS inner core heptosyl residues and the outer membrane protein OmpF as phage receptors. Based on RNA-sequencing and quantitative proteomics we also demonstrate the temperature dependent infection is due to strong repression of OmpF at 37°C. In addition, R1-RT was shown to be able to enter into a pseudolysogenic state. All together, this work provides further insight into phage-host cell interactions by highlighting the importance of understanding underlying factors which may affect the abundance of phage host receptors on the cell surface. [ABSTRACT FROM AUTHOR]