TABLE 1.

Distribution of fumC sequence polymorphisms among 36 E. coli isolates

Index strain for fumC sequence type (ECOR group of origin)bNo. of independent isolates with same fumC sequence typeNucleotide at the following candidate CGA-specific positions within fumCa:
270271288
MG1655 (group A)4GCC
CFT073 (group B2)8GTC
CP9 (group B2)4GCC
536 (group B2)2GCC
33 (group B1)5GCC
58 (group B1)1GCC
2P9 (group D)2GCC
44 (group D)1GCC
UMN026/CGA (group D)c4ATT
47 (group D)1ATT
35 (group D)d1ATC
46 (group D)d1ATC
37 (ungrouped)2GCC
  • a All three polymorphisms are synonymous; i.e., they do not alter the peptide sequence.

  • b fumC sequence groups were defined by the presence of one or more SNPs within fumC in comparison with the sequences of the other isolates. The ECOR group of origin was defined by multilocus enzyme electrophoresis ECOR strains 33, 58, 44, 47, 35, 46, and 37) (8) or multiplex PCR (the other isolates) (4).

  • c Data for CGA reference isolates are shown in boldface. These isolates included UMN026, SEQ102, V10, and V11 (13, 16).

  • d ECOR strains 35 and 46 were sequenced only after they were discovered to react with the initial putative CGA-specific primers.