Host Specificity of the Dickeya Bacteriophage PP35 Is Directed by a Tail Spike Interaction With Bacterial O-Antigen, Enabling the Infection of Alternative Non-pathogenic Bacterial Host.

Anastasia P Kabanova,Mikhail M Shneider,Kirill K Miroshnikov,Eugenia N Bugaeva,Stepan V Toschakov,Yuriy A Knirel,Aleksei A Korzhenkov,Evelina L Zdorovenko,Konstantin A Miroshnikov,Alexander N Ignatov,Eugene E Kulikov

doi:10.3389/fmicb.2018.03288

Abstract

Dickeya solani is a recently emerged virulent bacterial potato pathogen that poses a major threat to world agriculture. Because of increasing antibiotic resistance and growing limitations in antibiotic use, alternative antibacterials such as bacteriophages are being developed. Myoviridae bacteriophages recently re-ranked as a separate Ackermannviridae family, such as phage PP35 described in this work, are the attractive candidates for this bacterial biocontrol. PP35 has a very specific host range due to the presence of tail spike protein PP35 gp156, which can depolymerize the O-polysaccharide (OPS) of D. solani. The D. solani OPS structure, →2)-β-D-6-deoxy-D-altrose-(1→, is so far unique among soft-rot Pectobacteriaceae, though it may exist in non-virulent environmental Enterobacteriaceae. The phage tail spike depolymerase degrades the shielding polysaccharide, and launches the cell infection process. We hypothesize that non-pathogenic commensal bacteria may maintain the population of the phage in soil environment.

Highlights

Soft-rot Pectobacteriaceae (SRP) include phytopathogenic bacterial species from the genera Pectobacterium and Dickeya that cause economic losses in potato crops, as well as other vegetables and ornamental plants worldwide (Pérombelon, 2002)
The primary goal of the present study was an investigation of the D. solani – specific bacteriophage newly isolated in Russia and the molecular details of its interaction with the bacterial host
Bacteriophage PP35 was isolated in 2014 from sewage water in a potato storage warehouse (Moscow region, Russia) with a soft rot infection caused by D. solani

Summary

Introduction

Soft-rot Pectobacteriaceae (SRP) include phytopathogenic bacterial species from the genera Pectobacterium and Dickeya that cause economic losses in potato crops, as well as other vegetables and ornamental plants worldwide (Pérombelon, 2002). Treating seeds and harvested tubers with bacteriophages – viruses specific to particular bacterial pathogens – is considered a promising and environmentally safe strategy to protect plants and harvested crops from bacterial diseases (Frampton et al, 2012). (Czajkowski et al, 2014b, 2015) They have been thoroughly characterized and used to protect and control soft rot caused by D. solani. The primary goal of the present study was an investigation of the D. solani – specific bacteriophage newly isolated in Russia and the molecular details of its interaction with the bacterial host

Objectives

Methods

Results

Conclusion