Complete genome sequence of a copper-resistant Xanthomonas campestris pv. campestris strain isolated from broccoli in Mauritius suggests adaptive gene gain through horizontal gene transfer

Abstract

Bacterial adaptation is facilitated by the presence of mobile genetic elements (MGEs) and horizontal gene transfer (HGT) of genes, such as those coding for virulence factors or resistance to antimicrobial compounds. A hybrid assembly of Nanopore MinIon long read and Illumina short read data was produced from a copper-resistant Xanthomonas campestris pv. campestris (Xcc) strain isolated from symptomatic broccoli leaves in Mauritius. We obtained a 5.2 Mb high-quality chromosome and no plasmid. We found four genomic islands, three of which were characterized as integrative conjugative elements or integrative mobilizable elements. These genomic islands carried type III effectors and the copper resistance copLABMGF system involved in pathogenicity and environmental adaptation, respectively.