Genetic basis of copper-tolerance in Australian Pseudomonas syringae pv. tomato

  • Karina GriffinEmail author
  • P. Campbell
  • C. Gambley
Original Paper


The genetic basis of copper-tolerance in Australian Pseudomonas syringae pv. tomato (Pst) was investigated through PCR assays and genome analysis. Seven PCR assays were tested targeting copper metabolising (cop) genes, this included previously published assays as well as three new assays. These assays varied in their ability to detect cop genes in copper tolerant isolates and no one set of primers tested amplified all isolates, however, there is potential for these to be developed further for diagnostic purposes. The genomes of three copper tolerant isolates were sequenced using the Illumina platform. The genome assemblies of these isolates identified putative Cop and CopR/CusS operons homologous to those previously characterised in Pst as mediators of copper-tolerance. Analysis also suggests that the Cop and CopR/CusS operons may be located on either plasmid or chromosomal DNA, depending on the isolate studied. An additional CopAB complex was identified in the genomic assemblies of the three Pst isolates, and was homologous to chromosomal CopA and CopB in a copper sensitive Pst reference genome. Other potential copper metabolising genes were also identified. This is the first genomic analysis of copper tolerant Pst isolated outside of America, with PCR assays and genetic analysis revealing that the genetics of copper-tolerance in Pst is complex and diverse.


Pseudomonas syringae pv. tomato Bacterial speck disease Copper-tolerance Cop genes Polymerase Chain Reaction Genome Tomato 



This research was supported by the Australian Government Research Training Program (RTP) Scholarship and the Department of Agriculture and Fisheries, Queensland Australia. Pseudomonas sp. reference material kindly provided by: Agricultural Scientific Collections Trust, New South Wales Australia; Plant Pathology Herbarium of Biosecurity, Queensland Department of Agriculture and Fisheries Australia; and University of Florida, United States of America. We also acknowledge Philip Brown and Victoria MacKay for their editing contributions.


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Copyright information

© Australasian Plant Pathology Society Inc. 2019

Authors and Affiliations

  1. 1.Central Queensland UniversityBundabergAustralia
  2. 2.Department of Agriculture and FisheriesEco Sciences PrecinctDutton ParkAustralia
  3. 3.Department of Agriculture and FisheriesApplethorpe Research FacilityApplethorpeAustralia

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