TABLE 1

Bacterial strains and plasmids used in these studies

Strain or plasmidaDescriptionbReference(s) or source
Strains
    H10407Wild-type ETEC strain O78:H11; CFA/1; LT+/ST+; EtpA+56, 57
    E24377AWT ETEC strain O139:H2858
    B7AWT ETEC strain O148:H2859
    Nissle 1917O6:H1 probiotic strain originally isolated from an asymptomatic German soldier32
    HSIsolated from a healthy adult scientist at WRAIR; O9:H4; motile31
    jf1123H10407 derivative with isogenic deletion of gspE11
    jf1124H10407 derivative with isogenic deletion of gspM11
    jf1121H10407 derivative with isogenic deletion of gspG11
    TOP10F mcrA Δ(mrr-hsdRMS-mcrBC) ϕ80lacZΔM15 ΔlacX74 recA1 araD139 Δ(ara leu)7697 galU galK rpsL (Strr)Invitrogen
    yghJ mutantIsogenic insertion in yghJ; Kmr Cmr14
Plasmids
    pBAD/Myc-HisAArabinose-inducible expression plasmidInvitrogen
    pQL001yghJ cloned into XhoI and HindIII sites of pBAD/myc-HisA in frame with myc-His tagsThis study
    pQL117*Site-directed mutation of yghJ in codon corresponding to E1309(D)This study
    pQL114*Site-directed mutation of yghJ in codon corresponding to E1309(A)This study
    pQL150*Site-directed mutation of yghJ in codon corresponding to H1308(A)This study
    pQL152*Site-directed mutation of yghJ in codon corresponding to H1312(A)This study
    pQL124*66-nucleotide in-frame deletion in yghJThis study
  • a Mutagenized yghJ plasmids (indicated by asterisks) used plasmid pQL001 as a template for mutagenesis.

  • b WRAIR, Walter Reed Army Institute of Research; Strr, streptomycin resistant; Kmr, kanamycin resistant; Cmr, chloramphenicol resistant.