Genomic and phylogenetic analysis of a NDM-1 producing ST152 Klebsiella pneumoniae isolated from a bloodstream infection in China.

Purpose: The aim of this study was to characterize the genomic structure of the first isolated ST152 Klebsiella pneumoniae strain carrying bla in China.

Methods: Antimicrobial susceptibility was determined by broth microdilution method. Whole-genome sequencing was conducted using the Illumina HiSeq and Oxford Nanopore GridION X5 platforms, and the genomic features were analyzed using a range of bioinformatics tools.

Results: The strain HZKP1 demonstrated resistance to cefepime, ceftazidime, amoxicillin-clavulanic acid, amikacin, ciprofloxacin, meropenem, imipenem, and ertapenem, while showing sensitivity to tigecycline and colistin. It was classified as sequence type (ST) 152, K locus (KL) 105 and OC locus (OCL) O3b, respectively. The bla gene was identified on the IncX3 plasmid pHZKP1-NDM (54,035 bp), located downstream of the ISKox3-IS3000-ISAba125-IS5 segment and upstream of the ble-IS26-bla-IS26 segment. Phylogenetic analysis indicated its closest relative to be a strain isolated from a wound swab sample in Tanzania in 2013, differing by 598 alleles.

Conclusion: We characterized genomic features of the first ST152 K. pneumoniae strain isolated in China. Our findings provide insights into the current status of resistance in new lineages within the region and enhance comprehension of K. pneumoniae carbapenem resistance transmission from a genetic structure perspective.