Table 1.

Bacterial strains and plasmids used in this study

Strain or plasmidRelevant genotype or phenotypeaSource or reference
Strains
E. coliDH10BF′ mcrA Δ(mrr-hsdRMS mcrBC) φ80dlacZΔM15 ΔlacX74 deoR recA1 araΔ139 Δ(ara leu)7697 galU galK λ rpsL endA1 nupGStrr Life Technologies
E. coliMG-1Extended-spectrum cephalosporin resistance, Rifr Kanr Tobr GenrAmkr Sptr Strr SulrTetrCmr 51
Plasmidsb
 pPCR-script Amp (SK+)Ampr Stratagene
 pPCR-script Cm (SK+)Cmr Stratagene
 PBK-CMVNeorKanr Stratagene
 pNLT1Natural plasmid ofE. coli MG-1 containingbla VEB1 ESBL, RifrKanr Tobr Genr AmkrSptr Strr SulrCmr 51
 pRLT2pBKCMV recombinant plasmid containing an 11-kb Sau3A fragment withbla VEB-1 ESBL, KanrTmr Amkr Netr CmrSulr This work
 pRLT3pBKCMv recombinant plasmid containing a 13-kb Sau3A fragment withbla VEB-1 ESBL, KanrTmr Amkr NetrCmr This work
 pRLT4a and bpPCRscript recombinant plasmid containing a 1.3-kb PCR fragment withqacI; a, EtBrr CTABr; b, Etbrr CTABr This work
 pRLT5a and bpPCRscript recombinant plasmid containing a 1.8-kb PCR fragment with aacA1/orfG; a, Kanr TmrAmkr Netr; b, no resistance observedThis work
 pRLT6a and bpPCRscript recombinant plasmid containing a 2.7-kb PCR fragment with arr-2; a, Rifr; b, no resistance observedThis work
 pRLT7a and bpPCRscript recombinant plasmid containing a 3.8-kb PCR fragment withcmlA5; a, Cmr; b, Cmr This work
 pRLT8a and bpPCRscript recombinant plasmid containing a 3.2-kb PCR fragment with oxa10/aadA1; a, Ampr Strr Sptr; b, AmprStrr Sptr This work
 pRLT9a and bpPCRscript recombinant plasmid containing a 1.9-kb PCR fragment with the oxa10/aadA1 fusion cassette; a, AmprStrr Sptr; b, Ampr StrrSptr This work
 pRLT10a and bpPCRscript recombinant plasmid containing a 0.9-kb PCR fragment with theoxa10 cassette; a, Ampr; b, no resistance observedThis work
  • a Abbreviations: Kan, kanamycin; Tm, tobramycin; Net, netilmycin; Str, streptomycin; Spt, spectinomycin; Amk, amikacin; Cm, chloramphenicol; Tet, tetracycline; Sul, sulfonamide; Rif, rifampin; ESBL, extended-spectrum β-lactamase.

  • b For plasmids with “a” and “b” designations, “a” indicates recombinant plasmids where the inserted genes are in the same orientation as the Plac promoter of pPCRscript and “b” indicates recombinant plasmids where the inserted genes are in the orientation opposite that of thePlac promoter of pPCRscript.