Two Pantoea agglomerans type III effectors can transform nonpathogenic and phytopathogenic bacteria into host-specific gall-forming pathogens

Gal Nissan, Laura Chalupowicz, Guido Sessa, Shulamit Manulis-Sasson, Isaac Barash

Research output: Contribution to journalArticlepeer-review

Abstract

Pantoea agglomerans (Pa), a widespread commensal bacterium, has evolved into a host-specific gall-forming pathogen on gypsophila and beet by acquiring a plasmid harbouring a type III secretion system (T3SS) and effectors (T3Es). Pantoea agglomerans pv. gypsophilae (Pag) elicits galls on gypsophila and a hypersensitive response on beet, whereas P. agglomerans pv. betae (Pab) elicits galls on beet and gypsophila. HsvG and HsvB are two paralogous T3Es present in both pathovars and act as host-specific transcription activators on gypsophila and beet, respectively. PthG and PseB are major T3Es that contribute to gall development of Pag and Pab, respectively. To establish the minimal combinations of T3Es that are sufficient to elicit gall symptoms, strains of the nonpathogenic bacteria Pseudomonas fluorescens 55, Pa 3-1, Pa 98 and Escherichia coli, transformed with pHIR11 harbouring a T3SS, and the phytopathogenic bacteria Erwinia amylovora, Dickeya solani and Xanthomonas campestris pv. campestris were transformed with the T3Es hsvG, hsvB, pthG and pseB, either individually or in pairs, and used to infect gypsophila and beet. Strikingly, all the tested nonpathogenic and phytopathogenic bacterial strains harbouring hsvG and pthG incited galls on gypsophila, whereas strains harbouring hsvB and pseB, with the exception of E. coli, incited galls on beet.

Original languageEnglish
Pages (from-to)1582-1587
Number of pages6
JournalMolecular Plant Pathology
Volume20
Issue number11
DOIs
StatePublished - 1 Nov 2019

Keywords

  • Pantoea agglomerans
  • effectors
  • galls formation
  • host specificity
  • host-specific transcription activators
  • type III secretion system

Fingerprint

Dive into the research topics of 'Two Pantoea agglomerans type III effectors can transform nonpathogenic and phytopathogenic bacteria into host-specific gall-forming pathogens'. Together they form a unique fingerprint.

Cite this