Table 1.

Bacterial strains and plasmids used in this study

Strain and plasmidGenotype/characteristicsReference
E. coli strains
    NCK1831EC101 RepA+ host strain for pORI-based plasmids; Knr20
    NCK1911EC101 harboring pTRK93510
    NCK1978MC1061 harboring pTRK8928
L. acidophilus strains
    NCK56L. acidophilus NCFM
    NCK1829L. acidophilus NCFM harboring pTRK8928
    NCK1909L. acidophilus NCFM Δupp strain; W+10
    NCK1910NCK1909 harboring pTRK669, host for gene targeting insertion or replacement10
    NCK2136NCK1909 with gusA3 chromosomal insertion downstream of LBA0169 (slpA)This study
    NCK2139NCK1909 with gusA3 chromosomal insertion downstream of LBA1462 (lacZ)This study
    NCK2171NCK1909 with gusA3 chromosomal insertion downstream of LBA0889 (eno)This study
    NCK2190NCK1909 with gusA3 chromosomal insertion downstream of LBA0645 (low expression)This study
Plasmids
    pTRK669Temperature-sensitive helper plasmid; RepA+; Cmr29
    pTRK892Source of gusA3; Emr8
    pTRK935Counterselective integration vector with upp expression cassette; lacZ′; Emr10
    pTRK1020pTRK935 containing gusA3 between the upstream and downstream sequence flanking the LBA0169 integration siteThis study
    pTRK1022pTRK935 containing gusA3 between the upstream and downstream sequence flanking the LBA1462 integration siteThis study
    pTRK1039pTRK935 containing gusA3 between the upstream and downstream sequence flanking the LBA0889 integration siteThis study
    pTRK1045pTRK935 containing gusA3 between the upstream and downstream sequence flanking the LBA0645 integration siteThis study