Genomic epidemiology and molecular characteristics of blaNDM-1-positive carbapenem-resistant Pseudomonas aeruginosa belonging to international high-risk clone ST773 in the Gauteng region, South Africa
Hyunsul Jung, Johann Pitout, Yasufumi Matsumura, Kathy‐Anne Strydom, Chanel Kingsburgh, Marthie M. Ehlers, Marleen M. Kock
Abstract
Abstract Purpose The emergence of carbapenem-resistant P. aeruginosa (CRPA) harbouring acquired carbapenemase genes ( bla VIM , bla IMP and bla NDM ) has become a global public health threat. Three CRPA isolates included in the study had an extensively drug-resistant phenotype with susceptibility to colistin only and were positive for the bla NDM-1 gene. The current study aimed to investigate the genomic epidemiology and molecular characteristics of the bla NDM-1 -positive CRPA isolates collected from the Gauteng region, South Africa. Methods Short read whole genome sequencing (WGS) was performed to determine sequence types (STs), genetic relatedness, resistome, virulome and the genetic environment of the bla NDM-1 gene. Results The WGS and phylogenetic analyses revealed that the study isolates belonged to an international high-risk clone ST773 and belonged to the same clade with eight bla NDM-1 -positive ST773 isolates from Hungary, India, Nigeria, South Korea and USA. The study isolates harboured a wide repertoire of intrinsic and acquired antibiotic resistance genes (ARGs) related with mobile genetic elements, porins and efflux pumps, as well as virulence factor genes. The clade-specific ARGs ( bla NDM-1 , flo R2/ cml A9, rmt B4, tet G) were found in a putative integrative and conjugative element (ICE) region similar to ICE 6660-like . Conclusion As ICE carrying the bla NDM-1 gene can easily spread to other P. aeruginosa isolates and other Gram-negative bacteria, the findings in this study highlight the need for appropriate management strategies and active surveillance of CRPA isolates in the Gauteng region, South Africa.