Serotypes, Pathotypes, Shiga Toxin Variants and Antimicrobial Resistance in Diarrheagenic Escherichia coli Isolated from Rectal Swabs and Sheep Carcasses in an Abattoir in Mexico
Por:
Enriquez-Gomez, Edgar, Acosta-Dibarrat, Jorge, Talavera-Rojas, Martin, Soriano-Vargas, Edgardo, Navarro, Armando, Morales-Espinosa, Rosario, Velazquez-Ordonez, Valente, Cal-Pereyra, Luis
Publicada:
1 ago 2023
Resumen:
Sheep represent one of the main reservoirs of diarrheagenic Escherichia
coli; this microorganism is an etiological agent of food-borne diseases;
therefore, this work aimed to identify and characterize the principal
pathotypes of diarrheagenic E. coli (DEC) obtained through rectal swabs
and carcasses samples from sheep slaughtered in an abattoir at the
central region of Mexico. The isolates were subjected to bacteriological
identification, serotyping; phylogenetic classification; detection for
virulence factors, and antimicrobial sensibility. A total of 90 E. coli
isolates were obtained. It was observed through 49 E. coli isolates
(54%), 8 of them from carcasses, and 43 from feces was DEC. DEC
serotypes with health public relevance were found: O76:H19 (n = 5),
O146:H21 (n = 3), O91:H10 (n = 1), O6:NM (n = 1), and O8:NM (n = 1).
Regarding the presence of Shiga toxin-producing E.coli (STEC), 43/90
(47.7%) isolates have the stx1 w/o stx2 genes, and therefore were
assigned as STEC non-O157; only one isolate expressed stx1 and eae genes
and was classified as t-STEC (typical STEC). Additionally, 3/90 (3.3%)
harbored only the eae gene and were classified as enteropathogenic E.
coli (EPEC), the stp gene was found in 2/90 isolates (2.2%) and were
classified as enterotoxigenic E. coli (ETEC); 1/90 (1.1%) isolates
harboring the ipaH were classified as enteroinvasive E. coli EIEC.
Regarding stx1 genes subtypes, stx1c only was found in 60.5% (26/43),
followed by stx1a-stx1c 20.9% (9/43) and stx1a-stx1d 2.3% (1/43). The
presence of both, stx1 and stx2 genes was found in 7/43 isolates
(16.3%) from rectal swabs; the combination stx1c-stx2g was detected in
3/43 isolates (6.9%), while 4 (9.4%) isolates showed different
patterns (stx1a-stx1c-stx2g; stx1c-stx2b-stx2g; stx1c-stx2b and
stx1a-stx1c-stx2b-stx2g). STEC isolates showed the major diversity of
phylogenetic groups, although phylogroup B1 was predominant in 90.6%
(39/43) while there was only one isolate (2.3%) in each remaining
phylogroup (A, B2, C, and F). All EPEC, ETEC, and EIEC isolates were
clustered in phylogroup B1. We observed that 27.9% (12/43) of STEC
isolates carried at least one antibiotic resistance: nine isolates
expressed the tetB gene, one isolate the tetA gene, two isolates the
sul2 gene, one isolate the sul1 and one isolate the sul1-tetB genes.
These results highlight the importance of diarrheagenic E. coli as a
potential risk for public health during the slaughtering process.
Filiaciones:
Enriquez-Gomez, Edgar:
Center for Research and Advanced Studies in Animal Health, Faculty of Veterinary Medicine and Zootechnics, Universidad Autónoma del Estado de México, Toluca, C.P. 50295, Mexico
Acosta-Dibarrat, Jorge:
Center for Research and Advanced Studies in Animal Health, Faculty of Veterinary Medicine and Zootechnics, Universidad Autónoma del Estado de México, Toluca, C.P. 50295, Mexico
Talavera-Rojas, Martin:
Center for Research and Advanced Studies in Animal Health, Faculty of Veterinary Medicine and Zootechnics, Universidad Autónoma del Estado de México, Toluca, C.P. 50295, Mexico
Soriano-Vargas, Edgardo:
Center for Research and Advanced Studies in Animal Health, Faculty of Veterinary Medicine and Zootechnics, Universidad Autónoma del Estado de México, Toluca, C.P. 50295, Mexico
Navarro, Armando:
Department of Public Health, Faculty of Medicine, Universidad Nacional Autónoma de México, Mexico City, C.P. 04510, Mexico
Morales-Espinosa, Rosario:
Laboratory of Bacterial Genomics, Department of Microbiology and Parasitology, Faculty of Medicine, Universidad Nacional Autónoma de México, Mexico City, C.P. 04510, Mexico
Velazquez-Ordonez, Valente:
Center for Research and Advanced Studies in Animal Health, Faculty of Veterinary Medicine and Zootechnics, Universidad Autónoma del Estado de México, Toluca, C.P. 50295, Mexico
Cal-Pereyra, Luis:
Pathology Department, Veterinary Faculty, Universidad de la República, Montevideo, C.P. 1300, Uruguay
gold, All Open Access; Gold
|