Strains, plasmids, and DNA fragments used in this study

Strain, plasmid, or DNA fragmentRelevant characteristicsSource or referencea
    E. coli
        DH5αsupE44 ΔlacU169 (φ80lacZΔM15) hsdR17 recA1 endA1 gyrA96 thi-1 relA1Takara
        BL21(DE3)F ompT rB mB; DE3 is a λ derivative carrying lacI and T7 RNA polymerase genes under placUV5 controlTakara
        χ7213thi-1 thr-1 leuB6 fhuA21 lacY1 glnV44 ΔasdA4 recA1 RP4 2-Tc:Mu[λpir] Kmr9
        χ6097F ara Δ(pro-lac) rpsL ΔasdA4 Δ[zhf-2::Tn10] thi φ80dlacZΔM1525
    S. enterica serovar Choleraesuis
        C500Live vaccine attenuated from C78-1 by chemical methods; used to prevent piglet paratyphoid in China; serotype 6,7:C:1,5CIVDC
        C78-1Wild-type, virulent strainCIVDC
        C501Δasd derivative of C500This work
        C501(pYA-F1P2)C501 harboring pYA-F1P2This work
    B. bronchiseptica HH0809Wild-type, virulent strain originally isolated from a pig suffering from atrophic rhinitisLaboratory stock
        pBluescript SK(+)Phagemid cloning vector, ori ColE1 oriF1(+) bla lacZαStratagene
        pRE112oriT oriV Δasd Cmr sacB; counterselectable suicide plasmid22
        pET28a(+)IPTG-inducible expression vector; KmrNovagen
        pET-F1P2pET28a(+) derivative expressing rF1P2 with an N-terminal His6 tag; KmrThis work
        pYA3493Asd+ vector; pBR322 ori; derivative β-lactamase signal sequence-based periplasmic secretion plasmid17
        pYA-F1P2765-bp DNA encoding the type I region of FHA and R2 repeat domain of pertactin in pYA3493This work
DNA fragments
    F1465-bp fragment specifying the important immunodominant type I domain at the carboxy terminus of the FHA gene containing the most reactive epitopesThis work
    P2300-bp fragment specifying the repeated region II domain of the pertactin gene encoding an immunodominant protective epitopeThis work
  • a CIVDC, China Institute of Veterinary Drug Control (Beijing, China).