OBJECTIVES: The purpose of this study was to investigate the molecular epidemiology of CTX-M-14-producing Escherichia coli clinical isolates from Korea. METHODS: A total of 138 non-duplicate E. coli clinical isolates showing reduced susceptibility or resistance to ceftazidime and/or cefotaxime were included in the study. Resistance genes, genetic environment, R plasmid size and replicon type, sequence type (ST) and XbaI-macrorestriction patterns were determined. RESULTS: Among 138 isolates, 35 were found to carry the bla(CTX-M-14) gene. The ISEcp1 element was identified in the upstream region of the bla(CTX-M-14) gene in 32 isolates. The bla(CTX-M-14) gene was located on an IncF plasmid in 21 isolates, on an IncA/C plasmid in 1 isolate, on the chromosome in 8 isolates and on both the chromosome and an IncF plasmid in 5 isolates. The most prevalent ST was ST405 (n = 8), followed by ST354 (n = 4), ST38 (n = 3), ST69 (n = 3) and the intercontinental ST, ST131 (n = 3). PFGE and multilocus sequence typing experiments demonstrated no major clonal relationship among the CTX-M-14-producing isolates. CONCLUSIONS: The bla(CTX-M-14) gene was probably mobilized by IncF plasmids, which can readily spread in E. coli, causing horizontal dissemination of the resistance gene in Korea.
OBJECTIVES: The purpose of this study was to investigate the molecular epidemiology of CTX-M-14-producing Escherichia coli clinical isolates from Korea. METHODS: A total of 138 non-duplicate E. coli clinical isolates showing reduced susceptibility or resistance to ceftazidime and/or cefotaxime were included in the study. Resistance genes, genetic environment, R plasmid size and replicon type, sequence type (ST) and XbaI-macrorestriction patterns were determined. RESULTS: Among 138 isolates, 35 were found to carry the bla(CTX-M-14) gene. The ISEcp1 element was identified in the upstream region of the bla(CTX-M-14) gene in 32 isolates. The bla(CTX-M-14) gene was located on an IncF plasmid in 21 isolates, on an IncA/C plasmid in 1 isolate, on the chromosome in 8 isolates and on both the chromosome and an IncF plasmid in 5 isolates. The most prevalent ST was ST405 (n = 8), followed by ST354 (n = 4), ST38 (n = 3), ST69 (n = 3) and the intercontinental ST, ST131 (n = 3). PFGE and multilocus sequence typing experiments demonstrated no major clonal relationship among the CTX-M-14-producing isolates. CONCLUSIONS: The bla(CTX-M-14) gene was probably mobilized by IncF plasmids, which can readily spread in E. coli, causing horizontal dissemination of the resistance gene in Korea.
Authors: Amee R Manges; Hyun Min Geum; Alice Guo; Thaddeus J Edens; Chad D Fibke; Johann D D Pitout Journal: Clin Microbiol Rev Date: 2019-06-12 Impact factor: 26.132
Authors: M O Stokes; M Abuoun; S Umur; G Wu; S R Partridge; D J Mevius; N G Coldham; M D Fielder Journal: Antimicrob Agents Chemother Date: 2013-07-08 Impact factor: 5.191