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Characterization of a bla KPC-3 -carrying plasmid in a clinical isolate of Klebsiella pneumoniae belonging to the emerging successful clone ST147

Year: 2025

Type: article

Abstract: ABSTRACT Klebsiella pneumoniae ST147 has emerged as a successful clone able to efficiently disseminate a number of carbapenemases, including bla KPC . This study compared a representative bla KPC-3 -carrying plasmid of an ST147 clone with plasmids that usually harbor bla KPC-3 belonging to the high-risk clone ST512. Five clinical isolates of KPC-3-producing K. pneumoniae belonging to ST147 isolated in Southern Spain were analyzed. The first ST147 isolate detected was compared with two previous isolates of K. pneumoniae ST512/KPC-3 and KPC-3-encoding plasmid pKpQIL as reference plasmid. Microdilution, disk diffusion, β-CARBA test, and NG-Test CARBA 5 were used for antimicrobial susceptibility analysis and phenotypic characterization of the isolates according to EUCAST guidelines. Molecular characterization was performed using pulsed-field gel electrophoresis (PFGE)- Xba I, sequenced (by Illumina and Oxford Nanopore) and annotated with open-source databases (CGE tools and RAST). Plasmid incompatibility groups were analyzed using PlasmidFinder; BRIG was used to compare the bla KPC-3 -harboring plasmids from three of the selected clinical isolates with each other and with pKpQIL. Clinical isolates of ST147/KPC-3 showed resistance to β-lactams, fluoroquinolones, and aminoglycosides. Clinical isolates ST147/KPC-3 and ST512/KPC-3 had identical PFGE patterns in each clone. Plasmid replicon analysis showed a plasmid with the formula IncFII (K2:A-:B-) in the ST512 isolates, identical to pKpQIL; the ST147 isolates harbored IncFII (K1:A-:B-), although the genetic environment of bla KPC-3 was the same as pKpQIL, which is Tn 4401 _IS Kpn7 upstream of bla KPC-3 and IS Kpn6 downstream of bla KPC-3 . Plasmids harboring bla KPC-3 in ST147 and ST512 are different, although differences are subtle. The genetic environment of bla KPC-3 in the different sequence types is very conservative and identical to pKpQIL. IMPORTANCE The successful spread of bla KPC is primarily due to the dissemination of K. pneumoniae isolates belonging to high-risk clonal complex 258 (ST258, ST11, and ST512); however, new clones are emerging globally as the ST147 clone. In this study, we compare the genetic environment of a representative bla KPC-3 -carrying plasmid of an ST147 clone with plasmids that usually harbor bla KPC-3 belonging to the high-risk clone ST512. Plasmids harboring bla KPC-3 detected in ST512 and ST147 were different; however, the close genetic environments of bla KPC-3 in the different plasmids (ST147 and ST512) remained conserved.

Source: Microbiology Spectrum

DOI: 10.1128/spectrum.02338-24