TABLE 1.
Bacterial strains and plasmids used
| Strain or plasmid | Relevant genotype | Comment(s) (reference[s]) |
|---|---|---|
| Serovar Typhimurium strains | ||
| χ3181 | pStSR100+ | Virulence plasmid positive (12) |
| χ3306 | gyrA1816 pStSR100+ | Virulence plasmid positive, Nalr (12) |
| χ3337 | gyrA1816 pStSR100− | Virulence plasmid-cured derivative of χ3306, Nalr (12) |
| χ3456 | pStSR100::Tnminitet | Tnminitet insertion in the virulence plasmid; does not affect virulence, Tetr (12) |
| UF009 | pStSR100::vir-44::aph | aph insertion in the virulence plasmid that does not affect virulence; used as Kanr wild-type strain (10) |
| UF012 | pStSR100spvB5::aph | aph insertion in the spvB gene of virulence plasmid that attenuates virulence (10) |
| UF051 | pStSR100ΔspvB30 | ΔspvB30, deleting amino acids 21 to 555 of spvB (49) |
| UF110 | pStSR100ΔspvRABCD′::tet | spvRABCD′ replaced with tet in χ3181; Tetr (16, 17) |
| Plasmids | ||
| pACYC184 | Cloning vector (3) | |
| pGTR040 | spvRABCD′ cloned into pYA2204 (10) | |
| pGTR061 | spvRABCD cloned into pYA2204 (10) | |
| pGTR100 | 4-kb EcoRI fragment of the virulence plasmid carrying spvABCD cloned into EcoRI site of pACYC184 (10) | |
| pGTR127 | spvC cloned into pACYC184 on a BamHI-EcoRI fragment so that spvC is expressed from the tet promoter (11) | |
| pGTR147 | pGTR061 spvC22::Tn5 (10) | |
| pGTR153 | spvD cloned into pACYC184 so that spvD is expressed from the tet promoter (11) | |
| pGTR175 | PstI deletion derivative of pGTR100, removing open reading frame of spvA; encodes spvBC downstream of spvA promoter (this work) | |
| pGTR309 | PstI-EcoRI fragment of pGTR061 encoding spvB and spvC cloned into the PstI-EcoRI site of pUC118 (this work) | |
| pGTR333 | 2.4-kb EcoRI-StuI fragment of pGTR175 cloned into the EcoRI site of pACYC184; carries spvB downstream of the spvA promoter and is codirectional with cat promoter of pACYC184 (this work) | |
| pGTR337 | 2.4-kb EcoRI fragment from pGTR333 cloned into the EcoRI site of pYA2204; carries spvB downstream of the spvA promoter; spvB is in the opposite orientation from lacZ′ (this work) | |
| pGTR338 | 2.4-kb EcoRI fragment from pGTR333 cloned into the EcoRI site of pYA2204; carries spvB downstream of the spvA promoter; spvB is in the same orientation as lacZ′ (this work) | |
| pGTR339 | 2.2-kb MscI-EcoRI fragment of pGTR333 cloned into pYA2204 digested with SmaI and EcoRI; carries the ribosome-binding site, start codon, and open reading frame of spvB, with spvB in the same orientation as lacZ′ (this work) | |
| pGTR356 | SphI-EcoRI fragment of pGTR309 cloned into the SphI-EcoRI site of pMW119 spvBC is codirectional with lacZ′ of pMW119 (this work) | |
| pGTR357 | pGTR356 with point mutation abolishing start codon of spvC (this work) | |
| pMW119 | Cloning vector derived from pSC101 (Nippon Gene Co., Tokyo, Japan) | |
| pUC118 | Cloning vector, Ampr (44) | |
| pYA426 | spvCD cloned into pACYC184 as a BamHI fragment so that spvCD are expressed by the tet promoter (11) | |
| pYA2204 | Low-copy-number cloning vector, Ampr (8) |