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A Novel Deletion Mutation in pmrB Contributes to Concurrent Colistin Resistance in Carbapenem-Resistant Escherichia coli Sequence Type 405 of Clinical Origin.

ABSTRACT: We report the first clinical Escherichia coli strain EC3000 with concomitant chromosomal colistin and carbapenem resistance. A novel in-frame deletion, Δ6-11 (RPISLR), in pmrB that contributes to colistin resistance was verified using recombinant DNA techniques. Although being less fit than the wild-type (WT) strain or EC3000 revertant (chromosomal replacement of WT pmrB in EC3000), a portion of serially passaged EC3000 strains preserving colistin resistance without selective pressure raises the concern for further spread.

SUBMITTER: Wang CH

PROVIDER: S-EPMC7269477 | biostudies-literature |

REPOSITORIES: biostudies-literature

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