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AcrAB efflux pump plays a role in decreased susceptibility to tigecycline in Morganella morganii.

ABSTRACT: Transposon mutagenesis of a clinical isolate of Morganella morganii, G1492 (tigecycline MIC of 4 microg/ml), yielded two insertion knockout mutants for which tigecycline MICs were 0.03 microg/ml. Transposon insertions mapped to acrA, which is constitutively overexpressed in G1492, suggesting a role of the AcrAB efflux pump in decreased susceptibility to tigecycline in M. morganii.

SUBMITTER: Ruzin A

PROVIDER: S-EPMC547285 | biostudies-literature | 2005 Feb

REPOSITORIES: biostudies-literature

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AcrAB efflux pump plays a role in decreased susceptibility to tigecycline in Morganella morganii.

Ruzin Alexey A Keeney David D Bradford Patricia A PA

Antimicrobial agents and chemotherapy 20050201 2

Transposon mutagenesis of a clinical isolate of Morganella morganii, G1492 (tigecycline MIC of 4 microg/ml), yielded two insertion knockout mutants for which tigecycline MICs were 0.03 microg/ml. Transposon insertions mapped to acrA, which is constitutively overexpressed in G1492, suggesting a role of the AcrAB efflux pump in decreased susceptibility to tigecycline in M. morganii. ...[more]

PMID: 15673770

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