TABLE 1.
Strains and plasmids used in this study
| Strain or plasmid | Genotype | Relevant characteristics | Reference or source |
|---|---|---|---|
| Strains | |||
| MK233 | MT616/pRK2013 | Helper strain for triparental mating; Cmr | 9 |
| jf570 | H10407 ΔeltA | ETEC strain with polar insertion in eltA (LT deficient) | 8 |
| MK1052 | H10407 ΔeltA/pILT | jf570 carrying inducible LT plasmid; Ampr | 26 |
| MK1053 | H10407 ΔeltA/pTrc99A | jf570 carrying empty vector; Ampr | This work |
| MK1202 | H10407 ΔeltA/pILT[L25E] | As MK1052, with inducible L25E LT mutant; Ampr | This work |
| MK1201 | H10407 ΔeltA/pILT[Q3K] | As MK1202, with LT[Q3K]; Ampr | 26 |
| MK1239 | H10407 ΔeltA/pILT[Q3A] | As MK1201, with LT[Q3A]; Ampr | This work |
| MK1231 | H10407 ΔeltA/pILT[E11K] | As MK1201, with LT[E11K]; Ampr | This work |
| MK1240 | H10407 ΔeltA/pILT[E11A] | As MK1201, with LT[E11A]; Ampr | This work |
| MK741 | DH5α degP::Tn5/pDsbA/pILT | E. coli K-12 degP knockout, carrying a plasmid copy of dsbA and an inducible LT plasmid; Kanr Cmr Ampr | 26 |
| MK1101 | DH5α degP::Tn5/pDsbA/pILTB | As MK741, with pILTB; Kanr Cmr Ampr | This work |
| P4 | P27459 ΔctxAB | CT-deficient El Tor V. cholerae strain; Strr Kanr | 10, 11 |
| MK1123 | P4/pTrc99A | P4 carrying empty vector; Strr Kanr Ampr | This work |
| MK1225 | P4/pICTB | P4 carrying inducible CTB plasmid; Strr Kanr Ampr | This work |
| MK1236 | P4/pICTB[Q3K] | As MK1225, with inducible Q3K CTB mutant; Strr Kanr Ampr | This work |
| MK1232 | P4/pICTB[E11K] | As MK1225, with CTB[E11K]; Strr Kanr Ampr | This work |
| MK1233 | P4/pICTB[E11A] | As MK1225, with CTB[E11A]; Strr Kanr Ampr | This work |
| MK1242 | DH5α degP::Tn5/pDsbA/pICTB | As MK741, with pICTB; Kanr Cmr Ampr | This work |
| MK1223 | H10407 ΔeltA/pICTB | jf570 with inducible CTB plasmid; Ampr | This work |
| MK1224 | H10407 ΔeltA/pICTB[Q3K] | As MK1223, with inducible Q3K CTB mutant; Ampr | This work |
| MK1234 | H10407 ΔeltA/pICTB[E11K] | As MK1224, with CTB[E11K]; Ampr | This work |
| MK1235 | H10407 ΔeltA/pICTB[E11A] | As MK1224, with CTB[E11A]; Ampr | This work |
| MK1122 | P4/pILTB | P4 carrying inducible LTB plasmid; Strr Kanr Ampr | This work |
| MK1237 | P4/pILTB[Q3K] | As MK1122, with inducible Q3K LTB mutant; Strr Kanr Ampr | This work |
| MK1243 | P4/pILTB[Q3A] | As MK1122, with LTB[Q3A]; Strr Kanr Ampr | This work |
| MK1244 | P4/pILTB[E11K] | As MK1122, with LTB[E11K]; Strr Kanr Ampr | This work |
| MK1238 | P4/pILTB[L25E] | As MK1122, with LTB[L25E]; Strr Kanr Ampr | This work |
| Plasmids | |||
| pILT | IPTG-inducible LT holotoxin; Ampr | 26 | |
| pILTB | IPTG-inducible LTB pentamer; Ampr | This work | |
| pICTB | IPTG-inducible CTB pentamer; Ampr | This work |