Table 1.

Bacterial strains and plasmids

Strain or plasmidGenotype or descriptionReference or source
Strains
E. coliEDL933Prototypic O157:H7 EHEC strain 35
E. coli MC4100F Δ(argF-lac)U169 araD139 rpsL150 ptsF25 flbB5301 rbsR deoC relA1 29
E. coliRH90MC4100rpoS359::Tn10 29
E. coli GM37Wild type 19
E. coli GM230GM37hns 19
Plasmids
 pCR2.1Apr Kmr; high-copy-number vector for cloning of PCR productsInvitrogen
 pMAK700oriTCmr; mobilizable suicide vector bearing the oriT region of pJFF350 43
 pANK1Cmr Kmr; pMAK700oriT derivative containing additional cloning sites and the Kmr gene (aphA3) inserted in the HindIII restriction siteThis work
 pANK111Cmr Kmr; pANK1 derivative containing the 548-bp PCR fragment encompassing theespA gene containing an in-frame deletion, generated with primers 9188 and 9185This work
 pUJ9TTApr; multicopy promoter probe vector to generate fusions with thelacZ gene 23
 pUJ3Apr; pUJ9TT derivative containing a 653-bpBamHI PCR fragment generated with primers EspA-lac1 and EspA-lac2This work
 pUJ3-285Apr; pUJ9TT derivative containing a 371-bp EcoRV/BamHI fragment from pUJ3 inserted into the SmaI/BamHI sitesThis work
 pUJ3-56Apr; pUJ9TT derivative containing a 580-bp BamHI PCR fragment generated with primers EspA-lac1 and FAB 56This work