TABLE 1.
Strains and plasmids used in this study
| Strain or plasmid | Genotype or description | Reference or source |
|---|---|---|
| Strains | ||
| Enterobacter aerogenes BM2688 | Contains class 1 RI In40 with gene cassette array aac(6′)-Ib, qacF, cmlA2, and oxa-9 and the strong Pc variant (PcS). Resistant to tobramycin. | 13 |
| Shigella dysenteriae 3Sh | Contains class 1 RI with gene cassette array dfrA15-aadA1. Resistant to streptomycin, spectinomycin, and trimethoprim. | Laboratory collection |
| Escherichia coli 1314 | pSU38::catB9 | 14 |
| Escherichia coli DH5α | F− ϕ80dlacZΔM15 Δ(lacZYA-argF)U169 deoR recA1 endA1 hsdR17(rK− mK+) phoA supE44 λ- thi-1 gyrA96 relA1. Resistant to nalidixic acid. Used as recipient strain | Laboratory collection |
| Plasmids | ||
| pSU38ΔtotlacZ | Vector carrying the lacZ coding sequence with no translation initiation region or promoter | 8 |
| p1S | Integron 1S intI1-aac(6′)-Ib-dfrA15-aadA1-catB9 cloned into pSU38ΔtotlacZ with PcS promoter | This study |
| p1W | p1S mutated with primer PcWmut to create p1W with PcW promoter | This study |
| p1WTGN-10 | p1S mutated with primer PcWTGN-10mut to create p1WTGN-10 with PcWTGN-10 promoter | This study |
| p1SL | p1S mutated with primer LexAmut2L to create p1SL (constitutive expression of intI1R32_N39) | This study |
| p1WL | p1W mutated with primer LexAmut2L to create p1WL (constitutive expression of intI1R32_H39) | This study |
| p1WTGN-10L | p1WTGN-10 mutated with primer LexAmut2L to create p1WTGN-10L (constitutive expression of intI1P32_H39) | This study |
| pBad-intI1*R32_H39 | intI1 containing the PcW variant cloned into pBAD18 (arabinose-inducible expression vector) in which PcW is inactivated | 8 |
| pBad-intI1*R32_N39 | intI1 containing the PcS variant cloned into pBAD18 in which PcS is inactivated | 8 |
| pBad-intI1*P32_H39 | intI1 containing the PcWTGN-10 variant cloned into pBAD18 in which PcWTGN-10 is inactivated | 8 |
| p2S | Integron 2S intI1-catB9 cloned into pSU38ΔtotlacZ with PcS promoter | This study |
| p2W | p2S mutated with primer PcWmut to create p2W with PcW promoter | This study |
| p2WTGN-10 | p2S mutated with primer PcWTGN-10mut to create p2WTGN-10 with PcWTGN-10 promoter | This study |
| p2SL | p2S mutated with primer LexAmut2L to create p2SL (constitutive expression of intI1R32_N39) | This study |
| p2WL | p2W mutated with primer LexAmut2L to create p2WL (constitutive expression of intI1R32_H39) | This study |
| p2WTGN-10L | p2WTGN-10 mutated with primer LexAmut2L to create p2WTGN-10L (constitutive expression of intI1P32_H39) | This study |
| p3Sa | intI1-aac(6′)-Ib-catB9 cloned into pSU38ΔtotlacZ | This study |
| p4Sa | intI1-aac(6′)-Ib-aac(6′)-Ib-catB9 cloned into pSU38ΔtotlacZ | This study |
| p5Sa | intI1-dfrA15-aadA1-catB9 cloned into pSU38ΔtotlacZ | This study |
| p6Sa | intI1-aac(6′)-Ib cloned into pSU38ΔtotlacZ | This study |
| p7Sa | intI1-aac(6′)-Ib-dfrA15-catB9 cloned into pSU38ΔtotlacZ | This study |
| p8Sa | intI1-aadA1-catB9 cloned into pSU38ΔtotlacZ | This study |
| p9Sa | intI1-aac(6′)-Ib-dfrA15-aadA1- dfrA15-aadA1-catB9 cloned into pSU38ΔtotlacZ | This study |
| p10Sa | intI1 cloned into pSU38ΔtotlacZ | This study |
| p11Sa | intI1-aac(6′)-Ib-dfrA15-aac(6′)-Ib-dfrA15-aadA1-catB9 cloned into pSU38ΔtotlacZ | This study |
| p12Sa | intI1-aac(6′)-Ib-aac(6′)-Ib-dfrA15-aadA1-catB9 cloned into pSU38ΔtotlacZ | This study |
| p13Sa | intI1-aac(6′)-Ib-catB9-aac(6′)-Ib-catB9 cloned into pSU38ΔtotlacZ | This study |
| p14Sa | intI1-aac(6′)-Ib-dfrA15-aadA1-aac(6′)-Ib-dfrA15-aadA1-dfrA15-aadA1-catB9 cloned into pSU38ΔtotlacZ | This study |
| p15Sa | intI1-aac(6′)-Ib-catB9-catB9 cloned into pSU38ΔtotlacZ | This study |
| p16Sa | intI1- aac(6′)-Ib-dfrA15-aadA1-catB9- aac(6′)-Ib-dfrA15-aadA1-catB9 cloned into pSU38ΔtotlacZ | This study |
| p8741 | pBad::intI1Y312F | 20 |
| p1SintI1Y312F | p1S with the inactive integrase IntI1Y312F | This study |
a
Obtained after Cm pressure assays and cloned into pSU38ΔtotlacZ.