TABLE 1.

Relevant strains and plasmids

Strain or plasmidCharacteristicsSource or reference
Strains
    E. coli
        DH5αF φ80dlacZΔM15 Δ(lacZYA-argF)U169 endA1 recA1 hsdR17(rK mK+) deoR thi-1 supE44 gyrA96 relA1Life Technologies
        C43(DE3)BL21(DE3) carrying an unknown spontaneous mutation22
    C. perfringens
        JIR325Strain 13 Nalr Rifr19
        JIR4228JIR325 ΩTn916pfoR pfoA colA luxS)3
Plasmids
    pJIR751C. perfringens-E. coli shuttle vector, Emr5
    pJIR1972pJIR751(EcoRI/SphI)Ω pTS302(EcoRI/SphI; 3.8 kb) (pfoR+ pfoA+)4
    pTS302pUC19Ω(HindIII; C. perfringens; 4.3 kb) (pfoR+ pfoA+)39
    pJIR2098pJIR751(SmaI)Ω 3732/14518 PCR product (HindIII/T4 polynucleotide kinase; 1.034 kb)(ΔpfoR)This study
    pJIR2266pJIR2098(NsiI/Asp718)Ω 14349/5460 PCR product (NsiI/Asp718; 1.9 kb) (ΔpfoR+ pfoA+)This study
    pJIR2280pJIR2266(NsiI)Ω 14347/14348 PCR product (NsiI; 278 bp) (mutation in VirR box 1)This study
    pJIR2277pJIR2266(NsiI)Ω 14347/14348 PCR product (NsiI; 278 bp) (mutation in VirR box 2)This study
    pJIR2278pJIR2266(NsiI)Ω 14347/14348 PCR product (NsiI; 278 bp) (mutation in VirR box 1 and VirR box 2)This study
    pJIR2279pJIR2266(NsiI)Ω 14347/14348 PCR product (NsiI; 278 bp) (wild-type VirR boxes)This study
    pJIR2360pJIR2266(XbaI/PstI)Ω pJIR2224(XbaI/PstI; 2.0 kb) (Ω fragment+) (ΔpfoR+ pfoA+)This study
    pJIR2356pJIR2280 (XbaI/PstI)Ω pJIR2224(XbaI/PstI; 2.0 kb) (Ω fragment+) (mutation in VirR box 1)This study
    pJIR2357pJIR2277 (XbaI/PstI)Ω pJIR2224(XbaI/PstI; 2.0 kb) (Ω fragment+) (mutation in VirR box 2)This study
    pJIR2358pJIR2278 (XbaI/PstI)Ω pJIR2224(XbaI/PstI; 2.0 kb) (Ω fragment+) (mutation in VirR box 1 and VirR box 2)This study
    pJIR2359pJIR2279 (XbaI/PstI)Ω pJIR2224(XbaI/PstI; 2.0 kb) (Ω fragment+) (wild-type VirR boxes)This study
    pJIR2346pJIR751(BamHI/SmaI)Ω 9373/17104 PCR product (T4 polynucleotide kinase/BamHI; 395 bp) (ΔpfoR)This study
    pJIR2361pJIR2346(EcoRV/Asp718)Ω 17116/17117 PCR product (EcoRV/Asp718; 1.866 kb) (ΔpfoR+ pfoA+)This study
    pJIR2373pJIR2361(XbaI/PstI)Ω pJIR2224(XbaI/PstI; 2.0 kb) (Ω fragment+)This study
    pJIR2422pJIR2373(EcoRV)Ω 17443/17444 annealed complementary primers (EcoRV; 34 bp) (wild-type VirR boxes)This study
    pJIR2447pJIR2373(EcoRV)Ω 18705/18706 annealed complementary primers (EcoRV; 39 bp) (5-bp insertion between VirR boxes)This study
    pJIR2448pJIR2373(EcoRV)Ω 18707/18708 annealed complementary primers (EcoRV; 44 bp) (10-bp insertion between VirR boxes)This study
    pJIR2481pJIR2373(EcoRV)Ω 19211/19212 annealed complementary primers (EcoRV; 29 bp) (5-bp deletion between VirR boxes)This study
    pJIR2479pJIR2373(EcoRV)Ω 19190/19191 annealed complementary primers (EcoRV; 34 bp) (VirR boxes from upstream of CPE0845)This study
    pJIR2480pJIR2373(EcoRV)Ω 19206/19207 annealed complementary primers (EcoRV; 34 bp) (VirR boxes from upstream of CPE0920)This study
    pJIR2483pJIR2373(EcoRV)Ω 19192/19193 annealed complementary primers (EcoRV; 34 bp) (VirR boxes from upstream of CPE0846)This study
    pJIR2489pJIR2373(EcoRV)Ω 19208/19209 annealed complementary primers (EcoRV; 34 bp) (VirR boxes from upstream of hyp7)This study
    pJIR2632pJIR2373(EcoRV)Ω 20974/20975 annealed complementary primers (EcoRV; 39 bp) (5-bp insertion between VirR box 2 and −35 box)This study
    pJIR2620pJIR2373(EcoRV)Ω 20976/20977 annealed complementary primers (EcoRV; 44 bp) (10-bp insertion between VirR box 2 and −35 box)This study