Emergence of CTX-M-15 Extended Spectrum β-lactamase and ArmA-Producing Enterobacter cloacae

CTX-M-15형 Extended Spectrum β-lactamase와 ArmA 동시 생성 Enterobacter cloacae의 출현

  • Sung, Ji-Youn (Dept. of Biomedical Laboratory Sciencence, Far East University)
  • 성지연 (극동대학교 임상병리학과)
  • Received : 2015.10.25
  • Accepted : 2015.12.20
  • Published : 2015.12.28


We investigated the prevalence of extended spectrum ${\beta}$-lactamase (ESBL) genes and 16S rRNA methyltransferase genes to study antimicrobial resistance mechanisms of Enterobacter cloacae strains isolated from a university hospital in the Chungcheong province of Korea. Eight of the bacteria strains involved in this study contained CTX-M-15 type ESBL. Among 8 strains harboring the ESBL gene, 3 strains also harbored armA gene. The three isolates showed resistance to antimicrobial agents belonged to third cephalosporin, aminoglycoside, and fluoroquinolones. Furthermore, interspecies plasmid transfer of the antimicrobial resistant genes may induced horizontal spreading of the genes and emergence of multidrug resistant bacteria. Therefore, surveillance for existence of antimicrobial resistance determinants is important to prevent distribution of antimicrobial resistant strains.


Enterobacter cloacae;ESBL;antimicrobial agents;16S rRNA methyltransferase;CTX-M-15


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