Genomic insights into a Pseudomonas amygdali isolate from Hibiscus rosa-sinensis

The taxonomy of Pseudomonas has been extensively studied, yet the determination of species is currently difficult because of recent taxonomic changes and the lack of complete genomic sequence data. We isolated a bacterium causing a leaf spot disease on hibiscus (Hibiscus rosa-sinensis). Whole genome sequencing revealed similarity to Pseudomonas amygdali pv. tabaci and pv. lachrymans. The genome of this isolate (referred to as P. amygdali 35-1) shared 4987 genes with P. amygdali pv. hibisci, but possessed 204 unique genes and contained gene clusters encoding putative secondary metabolites and copper resistance determinants. We predicted this isolate's type III secretion effector (T3SE) repertoire and identified 64 putative T3SEs, some of which are present in other P. amygdali pv. hibisci strains. Assays showed that the isolate was resistant to copper at a concentration of 1.6 mM. This study provides an improved understanding of the genomic relatedness and diversity of the P. amygdali species.