Conservation of Erwinia amylovora pathogenicity-relevant genes among Erwinia genomes

Abstract

The Erwinia genus comprises species that are plant pathogens, non-pathogen, epiphytes, and opportunistic human pathogens. Within the genus, Erwinia amylovora ranks among the top 10 plant pathogenic bacteria. It causes the fire blight disease and is a global threat to commercial apple and pear production. We analyzed the presence/absence of the E. amylovora genes reported to be important for pathogenicity towards Rosaceae within various Erwinia strains genomes. This simple bottom-up approach, allowed us to correlate the analyzed genes to pathogenicity, host specificity, and make useful considerations to drive targeted studies.

Keywords: BLAST; Comparative genomics; Fire blight; Pathogenesis; Virulence factor.

Fig. 1

Heatmap hierarchical clustering: on the right, Erwinia strains are listed; on the bottom, genes important for virulence within E. amylovora are reported. Color code: green indicates a coverage ≥80% with an identity between 100% and 80%, yellow indicates a coverage ≥80% with an identity lower than 75%, red indicates a coverage lower than 75% that is interpreted as the absence of the paralogue. The genes are grouped according to the functional system: a exopolysaccharide metabolism, b sorbitol metabolism, c guanine derivative regulation, d desferrioxamine pathway, e type 1 secretion system, f type 3 secretion system, g others (transcription regulator, two-component transduction, positive regulator of virulence factor and sRNA chaperone). ^#These strains are Rosaceae-infecting apart from E. tasmaniensis ET1/99. The figure was rendered with the Krita software