Dataset Information

ISEc69-Mediated Mobilization of the Colistin Resistance Gene mcr-2 in Escherichia coli.

ABSTRACT:

Objectives

The emergence of mobile colistin resistance genes has compromised the efficacy of the last resort antibiotic, colistin, in clinical treatment. The mcr-2 gene was first identified in Belgium in association with the insertion sequence ISEc69. However, the molecular mechanisms of mcr-2 mobilization are not well understood.

Methods

To further explore the mobilization of mcr-2 gene via ISEc69, we constructed a conjugative plasmid that carries an intact composite transposon Tn7052. Transposition assays were performed by conjugation, the transposition sites were characterized by arbitrary primed PCR and DNA sequencing.

Results

In this study, we experimentally demonstrated that mcr-2 could be mobilized as a composite transposon Tn7052 and its transposition generated 8-bp AT-rich duplications in the host genome.

Conclusion

These results indicate that mcr-2 gene could be mobilized by ISEc69, the current investigations provide mechanistic insights in the transposition of mcr-2.

SUBMITTER: He YZ

PROVIDER: S-EPMC7835479 | biostudies-literature | 2020

REPOSITORIES: biostudies-literature

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Publications

IS<i>Ec69</i>-Mediated Mobilization of the Colistin Resistance Gene <i>mcr-2</i> in <i>Escherichia coli</i>.

He Yu-Zhang YZ Long Teng-Fei TF He Bing B Li Xing-Ping XP Li Gong G Chen Liang L Liao Xiao-Ping XP Liu Ya-Hong YH Sun Jian J

Frontiers in microbiology 20210112

<h4>Objectives</h4>The emergence of mobile colistin resistance genes has compromised the efficacy of the last resort antibiotic, colistin, in clinical treatment. The <i>mcr-2</i> gene was first identified in Belgium in association with the insertion sequence IS<i>Ec69</i>. However, the molecular mechanisms of <i>mcr-2</i> mobilization are not well understood.<h4>Methods</h4>To further explore the mobilization of <i>mcr-2</i> gene via IS<i>Ec69</i>, we constructed a conjugative plasmid that carri ...[more]

PMID: 33510713

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