Table 1.

E. coli strains used in this study

Bacteria	Characteristics	Source
AAEC185 (-)	Derived from E. coli K-12 strain, MM294, in which the fim operon is deleted. Also recA- [34].	Scott J. Hultgren, Washington Univ.
AAEC185/pSH2	The AAEC185 strain with the entire fim operon expressed from the pSH2 plasmid [35].
AAEC072	Derived from E. coli K-12 strain, MG1655. Deletion of fimB-H [34,36].	Ian Blomfield, Univ. of Kent
MG1655	Wild type E. coli K-12 (Fim+, but most cells are phased off for fimbrial expression
KB91	Derived from E. coli K-12 strain, MG1655, where the fim operon was deleted to produce AAEC191A [34]. The fimbrial M1L variant of FimH derived from intestinal E. coli was then expressed rom AAEC191A [25].	Evgeni V. Sokurenko, Univ. of Washington
Nu14	E. coli cystitis isolate that expresses the M1H variant of FimH [37].	Evgeni V. Sokurenko Univ. of Washington
J96	E. coli serotype O4:K6:45, a uropathogenic pyelonephritis isolate that expresses the M1H variant of FimH and P (PapG1 and G3) fimbriae.	Obtained from American Type Culture Collection (ATCC).