Genomic and functional characterization of carbapenem-resistant Klebsiella pneumoniae from hospital wastewater

Abstract

Background The emergence of carbapenem-resistant Klebsiella pneumoniae (CRKP) attracted extensive attention. Information on CRKP from hospital wastewater (HWW) is limited. The aims of this study were to investigate the genomic characteristics and to evaluate the survivability characteristics of 11 CRKP from HWW in a Chinese teaching hospital in Fujian province. Results A total of 11 CRKP from HWW were recovered in this study. All CRKP from HWW were resistant to most antibiotics. Comparative genetic analysis demonstrated that all CRKP isolates were clustered into the three distinct phylogenetic clades and clade 2 and clade 3 were mixtures of samples collected from both HWW and clinical settings. Varieties of resistance genes, virulence genes and plasmid replicon types were detected in CRKP from HWW. In vitro transfer of blaKPC-2 was successful for 3 blaKPC-2-positive CRKP from HWW with high conjugation frequency. Our study demonstrated that the genetic environments of blaKPC−2 shared core structure with ISKpn27-blaKPC−2-ISKpn6. Group analysis showed that CRKP from HWW had a lower survivability in serum compared to clinical CRKP (p < 005); and CRKP from HWW had no significant difference in survivability in HWW compared to clinical CRKP (p > 005). Conclusions We analyzed the genomic and survivability characteristics of CRKP from HWW in a Chinese teaching hospital. These genomes represent a significant addition of genomic data from the genus and could serve as a valuable resource for future genomic studies about CRKP from HWW.

Phenotypic identification of different β-Lactamases in intrinsic and acquired colistin resistant uropathogenic gram negative bacteria

“…7 The expression of AmpC enzymes is also associated with carbapenem resistance in K. pneumoniae strains lacking a 42 kDa outer membrane protein. 8 Treating Multi drug resistant bacteria, colistin was used as a last line of antibiotic for gram negative bacteria. 9 After the detection of mcr genes on plasmid of gram-negative bacteria disclosed that colistin resistance can be horizontally transferred.…”

“… 7 The expression of AmpC enzymes is also associated with carbapenem resistance in K. pneumoniae strains lacking a 42 kDa outer membrane protein. 8 …”