TABLE 1.
Serotypes and phenotypic and genotypic virulence markers of Escherichia coli O113 strains isolated from human and nonhuman sources in Brazila
| Source | Serotype | Cytotoxic activity | Ehx | Adherence pattern(s)b | stx1 | stx2 |
stx2c
|
ehxA | saa | lpfO113 | iha | EAEC gene | aggR | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| stx2vh-a | stx2vh-b | |||||||||||||
| Cattle | O113:H21 (19) | + | + (13) | AA3 (3), AA6 (11), DA3 (1), DA6 (2), NA (2) | + (7) | + | + (5) | + (6) | + (13) | + (13) | + | + | − | − |
| Buffalo | O113:H21 (1) | + | − | AA3 | + | + | + | − | − | − | + | + | − | − |
| Food | O113:H21 (1) | + | + | NA | − | + | − | − | + | + | + | + | − | − |
| Human diarrheac | O113:HNM (10) | − | − | AA3 (8), AA6 (1), NA (1) | − | − | − | − | − | − | + (1) | + (6) | + (8) | + (8) |
| O113:H4 (1) | − | − | AA3 | − | − | − | − | − | − | − | − | − | − | |
| O113:H7 (1) | − | − | AA6 | − | − | − | − | − | − | + | − | − | − | |
| O113:H10 (1) | − | − | AA6 | − | − | − | − | − | − | + | − | − | − | |
| O113:H12 (1) | − | − | AA3 | − | − | − | − | − | − | − | − | + | + | |
| O113:H21 (3) | − | − | AA3 (1), NA (2) | − | − | − | − | − | − | + | + (1) | − | − | |
a
Numbers in parentheses indicate the number of strains. All strains tested were negative for eae- and toxB-related sequences.
b
AA3, aggregative adherence in 3-h assay; AA6, aggregative adherence in 6-h assay; DA3, diffuse adherence in 3-h assay; DA6, diffuse adherence in 6-h assay; NA, nonadherent in 3- and 6-h assays.
c
In 12 of the 17 cases of human diarrhea, E. coli serogroup O113 was the only enteropathogen isolated from stool culture. Nine of the 17 human strains were recovered from patients suffering with AIDS.