Presence of activatable Shiga toxin genotype (stx(2d)) in Shiga toxigenic Escherichia coli from livestock sources.

ABSTRACT: Stx2d is a recently described Shiga toxin whose cytotoxicity is activated 10- to 1000-fold by the elastase present in mouse or human intestinal mucus. We examined Shiga toxigenic Escherichia coli (STEC) strains isolated from food and livestock sources for the presence of activatable stx(2d). The stx(2) operons of STEC were first analyzed by PCR-restriction fragment length polymorphism (RFLP) analysis and categorized as stx(2), stx(2c vha), stx(2c vhb), or stx(2d EH250). Subsequently, the stx(2c vha) and stx(2c vhb) operons were screened for the absence of a PstI site in the stx(2A) subunit gene, a restriction site polymorphism which is a predictive indicator for the stx(2d) (activatable) genotype. Twelve STEC isolates carrying putative stx(2d) operons were identified, and nucleotide sequen

SUBMITTER: Gobius KS 

PROVIDER: S-EPMC179786 | biostudies-literature | 2003 Aug

REPOSITORIES: biostudies-literature