Abstract
Shiga toxin-producing
Escherichia coli
(STEC) strains are considered as one of the major food-borne disease agents in humans worldwide. STEC strains, also called verotoxin-producing
E. coli
strains. The objectives of the present study were serotyping and molecular characterization of shiga toxigenic
E. coli
associated with raw meat and milk samples collected from Riyadh, Saudi Arabia. A total of 540 milk samples were collected from 5 dairy farms and 150 raw meat samples were collected from different abattoirs located in Riyadh, Saudi Arabia.
E. coli
were recovered from 86 milk samples (15.93%), serotyping of
E. coli
isolates revealed, 26 (4.81%) strains O157: H7, 23 (4.26%) strains O111, 20 (3.70%) strains O113: H21, 10 (1.85%) strains O22: H8 and 7 (1.3%) strains O172: H21. Meanwhile, 17 (11.33%) strains of
E. coli
were recovered from raw meat samples, serotyping of
E. coli
isolates revealed, 6 (4%) strains O157: H7, 5 (3.33%) strains O111 and 4 (2.67%) strains O174: H2 and only two (1.33%) strains were identified as O22: H8. Shiga toxin2 was detected in 58 (67.44%) serotypes of
E. coli
recovered from milk samples and 16 (94.12%) serotypes of
E. coli
recovered from meat samples, while intimin gene was detected in 38 (44.186%) serotypes of
E. coli
recovered from milk samples and in 10 (58.82%) serotypes of
E. coli
recovered from meat samples. The results of this study revealed the efficiency of combination between serotyping and molecular typing of
E. coli
isolates recovered from food of animal origin for rapid detection and characterization of STEC.