MOLECULAR CHARACTERIZATION OF TWO SHIGA-LIKE TOXIN PRODUCING ESCHERICHIA COLI ISOLATED FROM MINCED MEAT IN IRAQ

Abstract

Two strains of Escherichia coli O157: H7 were isolated from raw minced meat samples on sorbitol MacConkey agar supplemented with Cefixme and Tellurite (SMAC-CT) after selective pre-enrichment of the samples in enriched EHEC broth (EEB). The diagnosis was confirmed biochemically and serologically by latex agglutination. Resistance profile to antibiotics was almost similar in the two strains. Both strains were susceptible toward the probiotic Lactobacillus spp. Both contains single large plasmid but varies in their small plasmid content. The two strains contained shiga-like toxins stx1, stx2 as evidenced by amplified (224, 227 bp) DNA fragments. One strain contained eaeA gene 1087 bp amplified fragment. The results indicated that derivatives of E. coli O157:H7 containing stx may circulate in this type of local processed food. Stx genes can be targeted as molecular markers for epidemiological studies in the region.

Keywords

eaeA, stx genes, O157, Iraq