Dissemination of IncF group F1:A2:B20 plasmid-harbouring multidrug-resistant Escherichia coli ST131 before the acquisition of blaCTX-M in Japan

Michiko Hayashi; Mari Matsui; Tsuyoshi Sekizuka; Ayaka Shima; Takaya Segawa; Makoto Kuroda; Kumiko Kawamura; Satowa Suzuki

doi:10.1016/j.jgar.2020.10.021

Dissemination of IncF group F1:A2:B20 plasmid-harbouring multidrug-resistant Escherichia coli ST131 before the acquisition of bla_CTX-M in Japan

J Glob Antimicrob Resist. 2020 Dec:23:456-465. doi: 10.1016/j.jgar.2020.10.021. Epub 2020 Nov 17.

Authors

Michiko Hayashi¹, Mari Matsui², Tsuyoshi Sekizuka³, Ayaka Shima⁴, Takaya Segawa⁴, Makoto Kuroda³, Kumiko Kawamura⁵, Satowa Suzuki⁶

Affiliations

¹ Graduate School of Medicine, Nagoya University, Aichi, Japan; Antimicrobial Resistance Research Center, National Institute of Infectious Diseases, Tokyo, Japan.
² Antimicrobial Resistance Research Center, National Institute of Infectious Diseases, Tokyo, Japan.
³ Pathogen Genomics Center, National Institute of Infectious Diseases, Tokyo, Japan.
⁴ Department of Bacteriology II, National Institute of Infectious Diseases, Tokyo, Japan.
⁵ Graduate School of Medicine, Nagoya University, Aichi, Japan.
⁶ Antimicrobial Resistance Research Center, National Institute of Infectious Diseases, Tokyo, Japan. Electronic address: suzukiss@niid.go.jp.

PMID: 33212283
DOI: 10.1016/j.jgar.2020.10.021

Abstract

Objectives: The Escherichia coli O25-ST131 clone is responsible for global dissemination of the bla_CTX-M gene. However, the prevalence of this clone in the digestive tract, devoid of antimicrobial selection, and its molecular epidemiology remain unclear. In this study, we examined the origin of bla_CTX-M-positive E. coli O25-ST131 and its distribution.

Methods: We separately sequenced the chromosomal and plasmid genomes of 50 E. coli O25 isolates obtained from faecal samples of patients with diarrhoea in Japan.

Results: Although 36 (72%) of 50 E. coli O25 isolates were ST131, only 6 harboured bla_CTX-M. According to the fimH and ybbW sequences and fluoroquinolone susceptibility, H30R1 isolates were dominant (27/36; 75%) and possessed IncFII-FIA-FIB with FAB formula subtype F1:A2:B20 plasmids at a high frequency (24/27; 89%). The F1:A2:B20 plasmids possessed more resistance genes such as bla_TEM-1, aminoglycoside resistance genes and trimethoprim/sulfamethoxazole resistance genes compared with non-F1:A2:B20 plasmids. In contrast, only one bla_CTX-M-14 gene was located on the F1:A2:B20 plasmids, whereas the other three were located on IncFII (F4:A-:B-) (n = 1) and IncZ (n = 2) plasmids. Two H30Rx-ST131 isolates harboured bla_CTX-M-15: one was on the chromosome and the other on the IncFIA-R plasmid. The stability and conjugation ability of the F1:A2:B20 plasmids were compared with those of non-F1:A2:B20 plasmids, which revealed higher stability but lower conjugative ability.

Conclusions: These results suggest that E. coli H30R1-ST131 is a multidrug-resistant clone containing several resistance genes in the F1:A2:B20 plasmid, which were widely distributed before the acquisition of bla_CTX-M.

Keywords: CTX-M; Digestive tract colonization; ESBL; Escherichia coli ST131; IncF F1:A2:B20; Plasmid analysis.

Publication types

Research Support, Non-U.S. Gov't

MeSH terms

Escherichia coli Infections* / epidemiology
Escherichia coli* / genetics
Humans
Japan
Plasmids / genetics
beta-Lactamases / genetics

Substances

beta-Lactamases