TABLE 1.

Strains and plasmids used in this study

Strain or plasmidRelevant feature(s)aReference(s)
Strains
    L. plantarum
        WCFS1Single-colony isolate of L. plantarum NCIMB8826 28
        NZ5304Derivative of WCFS1 containing a lox66-P32-cat-lox71 replacement of bsh1 (bsh1:: lox66-P32-cat-lox71)This work
        NZ5305Derivative of NZ5304 containing a lox72 replacement of bsh1bsh1)This work
        NZ5334Derivative of WCFS1 containing a lox66-P32-cat-lox71 replacement of melA (melA:: lox66-P32-cat-lox71)This work
        NZ5335Derivative of NZ5334 containing a lox72 replacement of melAmelA)This work
        NZ5337Derivative of NZ5335 containing a lox72 replacement of melA and bsh1melA Δbsh1)This work
        NZ5338Derivative of NZ5335 containing a lox66-P32-cat-lox71 replacement of part of lacS2melA lacS2::lox66-P32-cat-lox71)This work
        NZ5339Derivative of NZ5338 containing a lox72 replacement of melA and part of lacS2melA ΔlacS2)This work
    E. coli
        DH5αCloning host; F′ φ80dlacZΔM15 endA1 recA1 hsdR17 (rK mK+) supE44 thi-1 gyrA96 relA1 Δ(lacZYA-argF)U169 deoR λ 63
        MC1061Cloning host; FaraD139 Δ(ara-leu)7696 galE15 galK16 Δ(lac)X74 rpsL (Strr) hsdR2 (rK mK+) mcrA mcrB1 16, 61
    L. lactis MG1363Plasmid-free derivative of NCDO 712 19
Plasmids
    pCR-BluntKanr; cloning vector for blunt-end PCR productsInvitrogen
    pGID023Emr; pJDC9 derivative containing the pE194 replication functions; unstable in lactobacilli 24
    pGIZ850Cmr Emr Apr; pUC18 derivative containing a P32-cat cassette that is selectable at the single-copy level 21
    pNZ273Cmr; pNZ124 carrying the promoterless gusA gene from E. coli 47
    pNZ5315Cmr Emr; pNZ7101 derivative containing a lox66 siteThis work
    pNZ5317Cmr Emr; pNZ5315 derivative containing a lox71 siteThis work
    pNZ5318Cmr Emr; pNZ5317 derivative for multiple gene replacements containing las and pepN terminatorsThis work
    pNZ5319Cmr Emr; pNZ5318 derivative for multiple gene replacements in gram-positive bacteriaThis work
    pNZ5340Cmr Emr; pNZ5319 derivative containing homologous regions up- and downstream of WCFS1 melAThis work
    pNZ5325Cmr Emr; pNZ5319 derivative containing homologous regions up- and downstream of WCFS1 bsh1This work
    pNZ5344Cmr Emr; pNZ5319 derivative containing homologous regions up- and downstream of lacS2 in the melA::lox72 strain NZ5335This work
    pNZ5346Cmr; pNZ273 derivative containing the promoter region and ribosome binding site of lp_1144 of WCFS1This work
    pNZ5347Cmr; pNZ7110 derivative containing the promoter region and ribosome binding site of lp_1144, driving expression of creThis work
    pNZ5348Emr; pGID023 derivative containing cre under the control of the lp_1144 promoterThis work
    pNZ7101Cmr Emr; pACYC184 derivative for gene replacements 8
    pNZ7110Apr; pUC18 derivative containing the cre gene 9
    pNZ84Cmr; pACYC184 derivative 59
  • a Kanr, kanamycin resistant; Cmr, chloramphenicol resistant; Emr, erythromycin resistant; Apr, ampicillin resistant.