TABLE 1.

Bacterial strains and plasmids used in this study

Strain or plasmidDescriptionSource or reference
Strains
    E. coli
        TOP10Cloning strainInvitrogen
        INV110dam and dcm methylase deficientInvitrogen
    M. morganii
        G858Clinical isolate, tigecycline MIC = 1 μg/mlThis study
        G1492Clinical isolate, tigecycline MIC = 4 μg/mlThis study
        GC7676G1492 insertion mutant, EZ::TN inserted in 453 bp of acrAThis study
        GC7677G1492 insertion mutant, EZ::TN inserted in 946 bp of acrAThis study
        GC7743GC7676 transformed with pCLL3444This study
        GC7744GC7677 transformed with pCLL3444This study
Plasmids
    pCR2.1-TOPOPCR cloning vectorInvitrogen
    pUCGmpUC19 derivative containing gentamicin resistance cassette13
    pCLL3443pCR2.1-TOPO with cloned acrAB genes (4,859-bp PCR fragment)This study
    pCLL3444pCLL3443 with cloned gentamicin cassette (878-bp XbaI fragment)This study