Diverse Escherichia coli pathovars of phylogroups B2 and D isolated from animals in Tunisia

Abstract

Introduction: The virulent Escherichia coli strains responsible for extraintestinal infections were mainly belonged to B2 and D phylogroups. However, no past studies have determinate via the presence of virulence genes the frequency of E. coli pathovars recovered from animals housed in farms in Tunisia. The aims of this study were to investigate 26 E. coli isolated from healthy and diarrheic animals and to determinate via the presence of virulence genes the frequency of pathovars. Methodology: Twenty-six E. coli isolates of phylogroups B2 (n = 14), B22 (n = 9), B23 (n = 5), and D2 (n = 12) were characterized. Genes encoding virulence factors (fimH,eaeA,aggC,papC, papG allele III, hlyA, east1, cnf1, exhA,stx1, stx2, iutA, fyuA, ibeA,and ipaH), and antibiotic resistance as well as class 1 and 2 integrons were searched by polymerase chain reaction (PCR). The genetic relationship of isolates was done by PFGE. Results: According to the occurrence of specific genes the 26 isolates were classified as:9 EAEC, 2 EHEC, 4 UPEC, 3 EPEC/EHEC and 1 NTEC. Therefore, 2 Ex-PEC and 5 APEC were presented amongst our strains. Some isolates (12) were clonal and the remaining was unrelated. Conclusions: Higher diversity of pathovars which carried diverse combinations of virulence genes in healthy isolates. In addition, it seems that the infections were caused by different mechanisms.

Antimicrobial susceptibility of Staphylococcus sp. and Escherichia coli isolated from captive Amazonian manatee (Trichechus inunguis)

“…Phylogroups A and D were detected in approximately 27% of the animals. These two phylogroups are more common in humans (BAILEY et al, 2010) and have been reported at lower frequencies in some animal species than those found in this study (KILANI et al, 2017;XAVIER et al, 2022). This detection raises two hypotheses: either isolates from phylogroups A and D are part of the microbiota of these animals, unlike some wild species already studied (CRISTÓVÃO et al, 2017;ZURFLUH et al, 2019), or there is external influence, such as contamination of riverbeds by human and domestic animal waste or transmission by contaminated feed (AMARSY et al, 2019;GUENTHER et al, 2011;KARAKAYA et al, 2022).…”

Study of the diversity of 16S–23S rDNA internal transcribed spacer (ITS) typing of Escherichia coli strains isolated from various biotopes in Tunisia

“…The frequency of phylogroups is lower (Carlos et al 2010;Jakobsen et al 2010). However, based on several studies, based on the presence of several virulence genes, B 2 and D phylogroups strains appear to be more toxic (Kilani et al 2017). Interestingly, no significant relationship was found between antibiotic resistance and the members of the phylogenetic group of the isolates.…”