Draft genome sequence of a carbapenemase-producing (NDM-1) and multidrug-resistant, hypervirulent Klebsiella pneumoniae ST11 isolate from Pakistan, with a non-hypermucoviscous phenotype associated with rmpA2 mutation.

OBJECTIVES

ST11 is a high-risk sequence type associated with carbapenem-resistant Klebsiella pneumoniae strains. Carbapenemase-producing hypervirulent K. pneumoniae (hvKp) are a major concern as they harbour a diverse range of pathogenicity traits. Here we describe the characteristics of K. pneumoniae strain KP75w isolated from a tertiary-care hospital in Pakistan.

METHODS

Antimicrobial susceptibility testing was performed by the Kirby-Bauer disk diffusion test and broth microdilution assay. The virulence phenotype was determined by string test as well as biofilm and cell adhesion assays. Genome sequencing was performed using MiSeq and HiSeq 2500 platforms with 30 × coverage.

RESULTS

Antimicrobial resistance profiling characterised strain KP75w as a multidrug-resistant carbapenemase-producing strain with a meropenem minimum inhibitory concentration (MIC) of 4 μg/mL, which is above the CLSI susceptible breakpoint (≤1 μg/mL). The annotated contigs indicated a genome size of 5 644 609 bp with 5679 coding regions. KP75w (ST11) was designated as a carbapenemase-producing hvKp strain on the basis of the presence of a carbapenemase gene (bla) and hypervirulence genes (rmpA2, iucABCD-iutA, fyuA, irp, mrk, ybt, fep and virB2). KP75w was found to contain a 163-kb virulence region showing 58.8% identity to the large virulence plasmid pLVPK, supporting the hypervirulence of KP75w.

CONCLUSION

KP75w is a novel non-hypermucoviscous carbapenemase-producing hvKp ST11 strain that appears to represent the convergence of multidrug resistance with hypervirulence traits in clinical K. pneumoniae strains from the Southeast Asian region.