Genomic Characteristics of a Klebsiella pneumoniae Strain Coproducing Carbapenemases KPC-2 and NDM-5

The aim of this study was to characterize the resistance gene of a Klebsiella pneumoniae strain coproducing carbapenemases KPC-2 and NDM-5. Klebsiella pneumoniae KPN-hnqyy, which is separated from the stool specimen of a patient, is resistant to all carbapenem antibiotics. Its MLST type is ST11. The genes of carbapenemases bla KPC-2 and bla NDM-5 are positive. The gene of conjugant bla KPC-2 is positive and that of conjugant bla NDM-5 is negative. Whole-genome sequencing shows that the strain contains one chromosome and three plasmids. The chromosome genomes of Klebsiella pneumonia such as KP69 and KP19-2029 are more than 99.9% similar to the chromosome genome of the strain studied; also, a similar IncR and IncFII resistance gene fusion region is contained in the different types of plasmids they carry: the bla KPC-2 gene is located in a structure—which evolved from the Tn3-△Tn4401-Tn1721/Tn1722 sequence—inside this fusion region with its ends inserted into the transposase IS26 gene; the bla NDM-5 gene is located on an I-shaped transposon containing the special plasmids of the insertion fragment in phages, with its ends inserted into the transposase IS26 gene, too.The Klebsiella pneumoniae KPN-hnqyy that carries both bla KPC-2 and bla NDM-5 may be derived from the bla KPC-2 carrying Klebsiella pneumoniae KP69 and KP19-2029 strains accidentally obtain the bla NDM-5 gene by the transfer of IS26 transposable elements. The wide transmission of Klebsiella pneumoniae ST11 carrying the bla KPC-2 gene in China and its ability to obtain other carbapenemase genes through transposable element IS26 are well worth attention.