Table 1.

Shigella strains and plasmids used in this study

Strain or plasmidRelevant genotype and/or phenotype or featureSource or reference
Strains
 2457TWild-typeS. flexneri serotype 2a 18
 BS103Virulence plasmid-cured 2457T 35
 BS2602457TmxiA::lacZ 6
 BS4732457T streptomycin resistantLab stock
 BS5472457T mxiM1(mxiM::aphA-3)This work
 BS548BS547/pRRS4 (mxiM1PBAD-mxiM +)This work
 BS575BS547/pRRS5 (mxiM1/PLAC-mxiM +)This work
 BS576BS547/pBAD18This work
 BS588BS547/pBluescript SK(+)This work
 BS5992457T/pRRS12 (mixiM +/PBAD-mxiM2)This work
 BS603BS547/pRRS12 (mxiM1/PBAD-mxiM2)This work
Plasmids
 pBAD18Arabinose-inducible PBAD expression vector 23
 pET19bVector used to construct histidine-tagged MxiMNovagen
 pGP704Suicide vector used to disruptmxiM 41
 pRRS11850-bp PCR generated fragment, extending from 912 bp upstream of themxiM start codon to 511 bp downstream of the stop codon, ligated with EcoRI-HindIII-digested pUC19This work
 pRRS2840-bp SmaI fragment of pUC18K (38), bearing aphA-3, ligated in the proper orientation with BspMI-digested (Klenow-treated) pRRS1This work
 pRRS32690-bp HindIII (Klenow-treated)-EcoRI fragment of pRRS2, bearing themxiM::aphA-3 allele, ligated withEcoRV-digested pGP704This work
 pRRS4484-bp PCR-generated fragment, extending from 19 bp upstream of themxiM start codon to 26 bp downstream of the stop codon, ligated with EcoRI-HindIII-digested pBAD18This work
 pRRS5484-bpEcoRI-HindIII fragment of pRRS4, bearingmxiM, ligated withEcoRI-HindIII-digested pBluescript SK(+)This work
 pRRS11370-bp PCR-generated fragment, extending from 67 bp downstream of the mxiM start codon (thus deleting signal sequence) to 10 bp downstream of the stop codon, ligated with NdeI-BamHI-digested pET19bThis work
 pRRS12Mutagenized mxiM allele encoding the G23R substitution, ligated withEcoRI-HindIII-digested pBAD18This work