TABLE 1.

Bacterial strains and plasmids

Strain or plasmidGenotype or phenotypeReference or source
Strains
    S. meliloti
        Rm1021SU47 str-21 Smr41
        Rm2011Smr wild type of RCR2011 (SU47)10
        SmA818Rm2011; pSymA cured45
        SRmA330Rm1021; fdoG::pKnock-GmrThis work
        SRmA402Rm1021; sma0478::pKanrThis work
        SRmA411Rm1021; fdsA::pKnock-TcrThis work
        SRmA442Rm1021; cah::pKnock-GmrThis work
        SRmA493fdsA fdoGHI ΦM12(SRmA411) → SRmA330a Gmr TcrThis work
        SRmA495sma0478 fdsA ΦM12(SRmA402) → SRmA411 Nmr TcrThis work
        SRmA497fdoG sma0478 ΦM12(SRmA330) → SRmA402 Gmr NmrThis work
        SRmA571fdoG sma0478 fdsA ΦM12(SRmA411) → SRmA497 Gmr Nmr TcrThis work
        SRmA580Rm1021; cbbF1::KanrThis work
    E. coli
        MM294Apro-82 thi-1 hsdR17 supE4422
        S17-1recA derivative of MM294A with integrated RP4-2 (Tc::Mu::Km::Tn7)54
        MT607MM294A; recA5622
        MT616MT607(pRK600)22
        DH5αλ φ80dlacZ°M15 °(lacZYA-argF)U169 recA1 endA1 hsdR17(rK mK) supE44 thi-1 gyrA relA126
        DH5αλpirλpir lysogen of DH5α28
Plasmids
    pBluescriptII SKCloning vector; ColE1 oriV AprStratagene
    pRK600pRK2013 npt::Tn9 Cmr22
    pRK415Tcr IncP broad-host-range cloning vector33
    pPH1JIIncP plasmid; Gmr8
    pKnock-TcSuicide vector for insertional mutagenesis; R6K ori RP4 oriT Tcr2
    pKnock-GmSuicide vector for insertional mutagenesis; R6K ori RP4 oriT Gmr2
    pKanpKNOCK-Gmr replaced with KmrThis work
    pBP1fdoG internal fragment in pKnock-GmThis work
    pBP3fdsA internal fragment in pBlueScriptThis work
    pBP6cbbF fragment in pBlueScriptThis work
    pBP9sma0478 internal fragment in pKnock-GmThis work
    pBP13sma0478 internal fragment in pKanThis work
    pBP15fdsA internal fragment in pKnock-TcThis work
    pBP19cah internal fragment in pKnock-GmThis work
    pBP20Kanr cassette cloned into cbbF fragment in pBP6This work
    pBP32cbbF::Kanr from pBP20 cloned into pRK415This work
    pMM22Kanr fragment cloned as a SmaI fragment into pBlueScriptThis work
  • a SRmA493 was constructed by ΦM12 transduction by transducing Tcr from SRmA411 into SRmA330. The transductants were subsequently screened for Gmr.