Genotyping and characterization of CTX-M-15 -producing Klebsiella pneumoniae isolated from an Iranian hospital

Abstract

The aims were to describe the genetic characterization of bla _CTX-M-1 group gene in Klebsiella pneumoniae and to investigate the relationship between isolates by MLVA and PFGE. We analyzed 36 CTX-M group 1-ESBL producing K. pneumoniae. rmpA and wcaG virulence genes were identified by PCR. The genetic environment of bla _CTX-M-1 was analyzed by PCR and sequencing. Plasmid replicons were determined using PCR-based replicon typing. The isolates were typed by MLVA and PFGE. All bla _CTX-M-1 were bla _CTX-M-15. The wcaG and rmpA were detected in 1 and 2 isolates, respectively. IncF were the most frequently detected replicons (63.88%). In all isolates, ISEcp1 was found upstream and orf477 downstream of bla _CTX-M-15, IS26 was found in two isolates. MLVA identified 20 MLVA types, whereas PFGE identified 25 different profiles. The dissemination of CTX-M-15 in our isolates was due to the clonal spread of isolates and to the genetic transfer of mobile elements among unrelated strains.

Keywords:

• CTX-M-15 β-lactamase
• MLVA
• Klebsiella pneumoniae
• IncF

Acknowledgements

This study was supported by a grant from Tarbiat Modares University, Faculty of Medical Sciences, Tehran, Iran. We are grateful to the staff of the microbiology laboratory at the Milad hospital for collecting K. pneumoniae isolates used in this study.