We examined their distribution in strains isolated from cases of diarrhea and asymptomatic controls. Different members of the Afa/Dr family were detected using specific primers for the adhesin-encoded genes (afaE). Their distribution is shown in Table 2. Table 2 Afa/Dr adhesins distribution in DAEC strains isolated from cases of
diarrhea and asymptomatic click here controls Strains isolated from Children Adults Diarrhea Control Diarrhea Control afaE N (%) N (%) Total N (%) N (%) Total 1 22 (44) 19 (32.8) 41 (38) 12 S3I-201 (44.4) 5 (33.3) 17 (40.5) 2 5 (10) 3 (5.2) 8 (7.4) 1 (3.7) 2 (13.3) 3(7.1) 3 1 (2) 1 (1.7) 2 (1.8) 2 (7.4) 1 (6.7) 3 (7.1) 5 1 (2) 2 (3.5) 3 (2.8) 1 (3.7)a 7 (46.7)a 8 (19) X 12 (24) 7 (12) 19 (17.6) 11 (40.7)a 0a 11 (40.7) daaE 3 (6) 9 (15.5) 12 (11) 0 0 0 1 + 2 5 (10) 0 5 (4.6) 0 0 0 1 + 3 0 1 (1.7) 1 (0.9) 0 0 0 1 + 5 0 6 (10.3) 6 (5.1) 0 0 0 1 + daaE 1 (2) 5 (8.6) 6 (5.1) 0 0 0 1 + 2 + daaE 0 1 (1.7) 1 (0.9) 0 0 0 2 + daaE 0 2 (3.5) 2 (1.8) 0 0 0 5 + daaE 0 2 (3.5) 2 (1.8) 0 0 0 Total 50 58 108 27 15 42
aP < 0.05 (cases x control). In 20% (30/150) of afaB-C-positive strains, the adhesin gene could not be identified. These strains with indeterminate afaE were referred to as “afa-X”. Strains isolated from children and adults exhibited KPT-8602 research buy a very different distribution of Afa/Dr adhesin encoding genes. The afaE-1 gene was a notable exception, being similarly distributed for all groups. It was also the most frequent gene. Strains isolated from children showed great diversity of adhesins. More than one type of Afa/Dr adhesins were detected in 21.3% (23/108) of strains isolated from children, and in 29.3% (17/58) of strains isolated from asymptomatic children. All genetic combinations involve afaE-1 or daaE. The afaE-1/afaE-2 association was found only in diarrheagenic strains (P < 0.05). The F1845 encoding gene was only found in strains isolated from check children, especially in control strains. Strains isolated from adults showed a low variability of afaE genes.
Prevalence of afa-X was higher (P < 0.01) in cases of diarrhea, while prevalence of afaE-5 was higher in controls (P < 0.01). Neither the daaE gene nor associations between two types of adhesins were detected in strains from adults. Distribution of virulence factors DAEC strains were examined regarding characteristics associated with virulence. The percentage of strains carrying virulence genes or possessing phenotypic characteristics associated to biofilm formation is summarized in Table 3. Table 3 Characteristics associated to virulence in DAEC strains possessing Afa/Dr genes isolated from children and adults Strains isolated from N(%) Children Adults Characteristic Diarrhea Control Diarrhea Control traA 45 (90) 47 (81) 19 (70.3) 13 (86.6) Cellulose 5 (10) 17 (29.3) 1 (3.7) 0 Curli 31 (62) 39 (67.2) 16 (59.2)a 1 (6.7)a sat 23 (46) 11 (18.9) 18 (66.7) 13 (86.6) TTSS 3 (6) 30 (51.