TABLE 2.
Strains and plasmids used in this study
| Strain or plasmid | Relevant genotype or phenotype | Source or reference |
|---|---|---|
| Strains | ||
| E. coli RR1023 | pOX38 recA56; susceptible strain | 9 |
| E. coli DH10B | araD139 Δ(ara leu)7697 deoR endA1 galK1 galU nupG recA1 rpsL F′ mrcA Δ(mrr-hsdRMS-mrcBC)φ80dlacZΔM15 ΔlacX74; streptomycin resistant | Stratagene |
| K. pneumoniae ILT-3 | Extended-spectrum cephalosporin-resistant isolate | 18 |
| Plasmids | ||
| pOX38 | 55 kb, F derivative, conjugative | 9 |
| pACYC184 | Chloramphenicol resistant | New England Biolabs |
| pILT-3 | Natural ca. 50-kb plasmid of K. pneumoniae ILT-3 producing β-lactamase CTX-M-19 | 18 |
| pC-1 | Recombinant plasmid pACYC184 with a 4,877-bp PCR fragment (primers PreA [5′-GCAGGTCTTTTTCTGCTCC-3′] and PreB [5′-TTTCCGCAGCACCGTTTGC-3′]) encompassing the potential transposon identified in pILT-3 | This study |
| pC-2 | Recombinant plasmid pACYC184 with a 3,635-bp PCR fragment (primers PreA and IS903B [5′-CCGTAGCGGGTTGTGTTTTC-3′]) containing ISEcp1B, blaCTX-M-19 gene, and truncated IS903D | This study |
| pC-2K | Recombinant plasmid pBK-CMV with the same 3,635-bp PCR fragment inserted into pC-2 | This study |
| pC-3 | Recombinant plasmid pACYC184 with a 4,606-bp PCR fragment (primers ISEcp1A [5′-GCAGGTCTTTTTCTGCTCC-3′] and PreB) containing blaCTX-M-19 and IS903D but lacking part of ISEcp1B | This study |