Dataset Information

Phenotypic and Molecular Characterization of an Enterobacter ludwigii Clinical Isolate Carrying a Plasmid-Mediated bla_IMI-6 Gene.

ABSTRACT: We report a plasmid-encoded IMI-6 carbapenemase in a clinical isolate of Enterobacter ludwigii from Spain. The isolate belongs to ST641 and was susceptible to expanded-spectrum cephalosporins and resistant to carbapenems. The modified carbapenem inactivation method (mCIM) test was positive, but β-Carba was negative. Whole-genome sequencing identified the bla_IMI-6 gene located in a conjugative IncFIIY plasmid and associated with the LysR-like regulator imiR. Both genes were bracketed by an ISEclI-like insertion sequence and a putatively defective ISEc36 insertion sequence. IMPORTANCE IMI carbapenemases confer an unusual resistance pattern of susceptibility to broad-spectrum cephalosporins and piperacillin-tazobactam but decreased susceptibility to carbapenems, which may make them difficult to detect in routine practice. Commercially available molecular methods for the detection of carbapenemases in clinical laboratories do not usually include bla_IMI genes, which could contribute to the hidden dissemination of bacteria producing these enzymes. Techniques should be implemented to detect minor carbapenemases that are not very frequent in our environment and control their dissemination.

SUBMITTER: Blanco-Martin T

PROVIDER: S-EPMC10269617 | biostudies-literature | 2023 Jun

REPOSITORIES: biostudies-literature

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Phenotypic and Molecular Characterization of an Enterobacter ludwigii Clinical Isolate Carrying a Plasmid-Mediated blaIMI-6 Gene.

Blanco-Martín T T Guzmán-Puche J J Riazzo C C Gasca-Santiyán M M Hernández-García M M Cantón R R Torre-Cisneros J J Herrera C C Martínez-Martínez L L

Microbiology spectrum 20230419 3

We report a plasmid-encoded IMI-6 carbapenemase in a clinical isolate of Enterobacter ludwigii from Spain. The isolate belongs to ST641 and was susceptible to expanded-spectrum cephalosporins and resistant to carbapenems. The modified carbapenem inactivation method (mCIM) test was positive, but β-Carba was negative. Whole-genome sequencing identified the blaIMI-6 gene located in a conjugative IncFIIY plasmid and associated with the LysR-like regulator imiR. Both genes we ...[more]

PMID: 37074170

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Project description:Carbapenem-resistant Enterobacteriaceae strains have emerged as a serious threat to global public health. In recent years, blaIMI, a carbapenemase gene that drew less attention before, has been increasingly detected in both clinical and environmental settings. However, the environmental distribution and transmission of blaIMI, especially in aquaculture, require systematic investigation. In this study, the blaIMI gene was detected in fish (n = 1), sewage (n = 1), river water (n = 1), and aquaculture pond water samples (n = 17) collected from Jiangsu, China, demonstrating a relatively high sample-positive ratio of 12.4% (20/161). Thirteen blaIMI-2- or blaIMI-16-carrying Enterobacter asburiae strains were isolated from blaIMI-positive samples of aquatic products and aquaculture ponds. We also identified a novel transposon (Tn7441) carrying blaIMI-16 and a conserved region containing several truncated insertion sequence (IS) elements harboring blaIMI-2, all of which may play important roles in blaIMI mobilization. The occurrence of blaIMI-carrying Enterobacter asburiae in aquaculture-related water samples and fish samples highlights the risk of transmission of blaIMI-carrying strains through the food chain and the need for effective measures to prevent further dissemination. IMPORTANCE IMI carbapenemases have been detected in clinical isolates of many bacterial species with systemic infection and cause a further burden on clinical treatment in China, but their source and distribution are still unclear. The study systematically investigated the distribution and transmission of the blaIMI gene in aquaculture-related water bodies and aquatic products in Jiangsu Province, China, which is famous for its rich water resources and developed aquaculture industry. The relatively high prevalence of blaIMI in aquaculture samples and the identification of novel mobile elements harboring blaIMI enhance our knowledge of blaIMI gene distribution and highlight the public health risk and urgency of surveillance of aquaculture water systems in China.

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Dataset Information

Phenotypic and Molecular Characterization of an Enterobacter ludwigii Clinical Isolate Carrying a Plasmid-Mediated bla_IMI-6 Gene.

Publications

Phenotypic and Molecular Characterization of an Enterobacter ludwigii Clinical Isolate Carrying a Plasmid-Mediated <i>bla</i><sub>IMI-6</sub> Gene.

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